Preface to the 6 - ISCA 978-93-84648-83... · 2017-07-30 · 2015 International E - Publication , Preface to the 6th National Conference The Department of Engineering Sciences, MIT

2015

International E - Publication www.isca.me, www.isca.co.in

Preface to the 6th

National Conference

The Department of Engineering Sciences, MIT Academy of Engineering, Alandi, Pune has organized

the 6th National Conference on ‘Multidisciplinary Research in Science and Engineering (NCMRSE-

2015)’ on 5th-6

th June, 2015. From the excellent response that the earlier Conferences received and

the enthusiasm shown by the participants, we are encouraged to make it a regular feature and hold it

periodically.

Engineering and Applied Sciences are not only scientifically rich subjects; they also possess

extensive range of applications in many other fields such as: Engineering, Industry, Medical Sciences,

Ecology, Economics and Finance, Military Applications, Technology, and many others. It is almost

impossible to conceive of a quantitative discipline in which Engineering sciences do not play a

fundamental role.

As our duty to be well positioned to steer our students toward improving their education and learning,

this conference aims to advance the Applied Sciences through presentation of original

multidisciplinary research articles in almost all disciplines of Engineering. The main objective of this

conference is to provide impetus and motivation for further research work and directions for

multidisciplinary and interdisciplinary research. We aim at bringing together academicians,

researchers and people using multidisciplinary sciences in industry and elsewhere, to share their

knowledge and exchange views and ideas. This will facilitate to discuss future prospects in the field of

engineering applications. The general objective is to create awareness among the teachers about the

beauty of various real life and Industrial applications of engineering & applied Sciences.

We are happy to present the ‘Proceedings of NCMRSE-2015’, bearing ISBN: 978-93-84648-83-1. Out

of total 68 research articles received, this proceeding contains 16 selected, modified, reviewed and

edited research articles presented at the Conference. All selected articles have been checked for

plagiarism. We are happy to communicate that total 70 participants have participated comprising of 54

oral presentation which also includes eight international participants and one visually impaired

participant.

We are thankful to all the participants, chairmen of the sessions and invited speakers for their

contributions. Our thanks are also due to session referees who have evaluated and selected papers

in two categories for best paper award.

We also gratefully acknowledge the contributions from all those who participated in various ways

directly or indirectly to make this Conference a great success.

My special thanks to our Executive Director Dr. Sunil Karad and Principal, Dr. Y. J. Bhalerao for their

wholehearted support and continuous encouragement for promoting & strengthening interdisciplinary

research at MIT AOE.

On behalf of the organizing committee,

Dr. S. M. Khairnar Convener NCMRSE-2015

International E - Publication 427, Palhar Nagar, RAPTC, VIP-Road, Indore-452005 (MP) INDIA

Phone: +91-731-2616100, Mobile: +91-80570-83382

E-mail: [email protected], Website:www.isca.me , www.isca.co.in

6th National Conference on Multidisciplinary Research in Science and

Engineering (NCMRSE)-2015, 5th-6th June, 2015

Organised by:

MIT Academy of Engineering,

Alandi (D), Pune-412105

© Copyright Reserved

2015

All rights reserved. No part of this publication may be reproduced, stored, in a

retrieval system or transmitted, in any form or by any means, electronic,

mechanical, photocopying, reordering or otherwise, without the prior permission

of the publisher.

ISBN: 978-93-84648-83-1

CONTENTS

S.No. Author(s) Title of research paper Page nos.

1 B. Patidar, M. M. Hussain, A.

P. Tiwari

Analytical And Numerical Validation Of Coil

And Work Piece Parameters In Induction

Heating Process

1-11

2 V.A.Tarange, A.M.Kotha, P

R Thakur

Glycidyl Methacrylate-Divinyl Benzene

Polymeric Adsorbents For Removal Of O-

Cresol From Aqueous Solution

12-20

3 Mrs. Sarika Dinesh Patil,

Sumant G Kadwane

Selective Harmonic Reduction Technique For

A Multilevel Inverter Using Optimization

Approach

21-31

4 V.S. Jagadale, Prof. Dr. P.G.

Gaikwad

Optimisation Of Stockyard Layout In Concrete

Product Industry

32-36

5 Andhare Vipul, Mahajan

Prathamesh, Panzade Amol,

Joshi Apurv

A Survey On Link Prediction Using Temporal

Approach

37-46

6 Dhananjay Bhole Issues Of Persons With Disabilities And

Accessibility Standards Implementation

47-50

7 Ishwar Khuspe, Dr. M. V.

Bhatkar

Cost Effective Street Lights Monitoring

System (Cesmos)

51-62

8 Priya Francis, S.V. Ghaisas Li Intercalation Process In

Si10h15/Monovacancy Graphene Monolayer

Composite - Implications Towards Li-Ion

Batteries

63-70

9 Sonawane D. S., Hiwarekar

A. P., Dhanorkar G. A.

Honey Bees Have Geometrical Sense: A

Mathematical Approach

71-77

10 Saikat Ghosh, Dr. Amaresh

Kumar

Impact Of Quality Management On

Macroeconomic Variables

78-89

11 Sanket Garade, Prof. Dr.

Rajiv B.

Design And Development Of Computer

Controlled Electro-Mechanical Mount For

Maneuvering An Astronomical Telescope

90-96

12 Selva Hepshibha, Dr. P.P. GaN Scintillator Detector Characterization 97-104

Vaidya Simulation Geant4 Software And Voltage Pre-

Amplifier Simulation

13 S. D. Katore, R. S. Rane, S.

S. Dabhane

Proper Homothetic Vector Field For Maximal

Symmetric Transverse Spaces

105-107

14 P.V. Bhamare, Dr. Rajiv B,

Mr. B. N. Sadavarte

Poka-Yoke Auto Checking System For B-

Pillar Assembly Component

108-117

15 Aatray Kumar Singh Proteo: A New Approach To Network-On-Chip 118-127

16 Abhijit B. Dalvi FinFET Technology: A Review 128-133

Proceedings of 6th National Conference on Multidisciplinary Research in Science & Engineering, MIT AOE Alandi, Pune, 5-6 June 2015 ,pp. 1-11, ISBN: 978-93-84648-83-1

International Science Congress Association

www.isca.in , www.isca.co.in , www.isca.net.co , www.isca.net.in

ANALYTICAL AND NUMERICAL VALIDATION OF COIL AND WORK PIECE PARAMETERS IN INDUCTION

HEATING PROCESS

B. PATIDAR1, M. M. HUSSAIN1, A. P. TIWARI2 1Atomic Fuels Division

2Reactor Control Division

Bhabha Atomic Research Centre, Mumbai

Abstract

In this paper, induction coil and work piece parameters are calculated by analytical and numerical methods at different frequency. In analytical method, induction coil and workpiece are represented by using series equivalent circuit (SEC). In analytical formulation, Nagaoka factors are used to accurately predict the coil equivalent impedance and work piece power. Workpiece resistance and reactance are calculated by using Bessel’s functions. In numerical method, magnetic vector potential formulation and finite element method are used to calculate the magnetic field and other parameters related to induction coil and workpiece. Analytically and numerically calculated parameters are compared and found that they are in good agreement. This analysis can be applied for design and optimization of induction coil for forging and melting applications.

Key Words: induction heating, FEM, coil design

1. INTRODUCTION

Induction heating is based on faraday’s law of electromagnetic induction. It is widely utilized in

industries for heating, melting, forging, welding, hardening etc, because of its good efficiency and

cleanliness [1], [2]. Induction heating is multiphysics process and it involves electromagnetic, heat

transfer and fluid dynamics. All the physics are tightly coupled with each other, which makes

difficult to design the induction coil for specific application. Induction coil design involves selection

and optimization of various parameters like coil diameter, coil tube diameter, no of turn, coil pitch,

coil current, frequency etc.

Induction coil design and optimization can be done either by analytical method or numerical

method [3]. In analytical method, induction coil resistance and reactance are calculated by

empirical formulas and work piece resistance and reactance are calculated by solving field

2 B.Patidar, M.M. Hussain, A.P.Tiwari



equation using series solution method. Nagaoka correction factors are used to accurately calculate

workpiece power and magnetic field produced by the induction coil [4].

In numerical method, magnetic vector potential formulation is used to calculate the magnetic

field surrounding the induction coil. It requires less computation compared to magnetic field

formulation [5]. Magnetic vector potential equations are solved by using finite element method

(FEM). FEM solution is used to calculate the coil and workpiece parameters.

This paper is subdivided into following sections, section 1.1, gives brief introduction to induction

heating process. Section 1.2, describes the analytical formulation used for calculation of

induction coil and work piece parameters. Section 1.3, gives the numerical method details and

procedure used for calculation of work piece and coil parameters. Section 2, gives the

comparison and analysis of analytical and numerical results. Conclusion of the analysis is given

in section 3.

1.1. Induction heating process

In induction heating process, induction coil carries high frequency current and produces time

varying magnetic field. This time varying magnetic field generates eddy current in the

conducting object (workpiece) placed near to the coil as shown in the figure (1). Eddy current

heats the workpiece by joules effect. In most of the induction heating process, work piece

placed inside the induction coil, because of high magnetic flux density.

R'w

Xg

Xc X'w

VL

ICICIC

Rc

Dc

dc

Sc

Dw

lclw

Refractory

Copper Induction Coil

Graphite Billet

z

r

Figure 1(a) 2-D geometry of induction coil and workpiece. 1(b). Series equivalent circuit of

Coil and workpiece

1.2. Analytical formulation

Induction heating process can be analyzed by series equivalent circuit (SEC) or transformer

equivalent circuit (TEC) [6]. In this paper, SEC technique is used. SEC analysis is based on

Analytical and Numerical Validation of Coil and Work-Piece Parameters in Induction Heating Process

3



magnetic flux division between induction coil, air gap and workpiece. Based on magnetic flux

division, there are three reactance’s i.e. coil reactance, air gap reactance and workpiece reactance

[7]. Series equivalent circuit of induction heating process is shown in the figure 1(b).SEC

parameters are calculated by using following analytical formulas [4],

Coil resistance (1)

Space factor (2)

Here,

ρ=Resistivity of coil material (Ω-m)

kr= Space factor

Nc= No of turn

= Skin depth (m) in coil

= Coil inner diameter (m)

lc= coil length(m)

=Inter turn air gap (m)

Coil reactance XC=RC, for (δc<0.5tc) (3)

Here,

tc=Coil tube thickness(m)

Air gap reactance

Air gap reactance is most dominating reactance in induction heating process, and that

is minimized by reducing air gap between workpiece and induction coil. Air gap reactance

is calculated by Eq (4),

(4.1)

(4.2)

(4.3)

Here,

dw = work piece diameter(m)

µ0= Air permeability(4πx10-7 H/m)

kn*= frequency dependent correction factor

kn= Short coil correction factor

= Skin depth (m) in workpiece

Workpiece resistance and reactance




Workpiece resistance and reactance are calculated by using Bessel functions that gives

more accurate results compared to standard formulas. Workpiece resistance and reactance

are calculated by using following formulas,

Work piece resistance (5.1)

Work piece inductive reactance (5.2)

(6.1)

(6.2)

(6.3)

Here,

=dimensionless reference depth

Correction factor accounting for the average phase shift between

current and voltage in the work piece

ber, ber’, bei, bei’= real and imaginary parts of zero order modified Kelvin Bessel

functions and their derivatives.

Combination of eq (1), (3), (4.1), (5.1), (5.2) gives the equivalent circuit impedance,

(7)

Voltage across induction coil

(8)

Here,

Ic= coil current (A)

Power loss in induction coil helps to find out the cooling requirements to maintain coil

temperature below 303 Deg K. It is calculated by

eq (9),

(9)

Power induced in the workpiece is calculated by using eq (10),

(10)

1.3. Finite Element formulation of Electromagnetic Field

Electromagnetic field produced by induction coil can be represented by maxwell equations

[8]. Maxwell equations are combination of four laws i.e gauss law, gauss magnetism law,

faraday law of induction, and ampere law as shown below,

(11.1)


5



(11.2)

(11.3)

(11.4)

Here, H:- Magnetic field strength (A/m)

E: - Electric field strength (V/m)

σ: - Electrical conductivity (S/m)

J= Current density (A/m2)

Induced current density is much higher than displacement current density, therefore,

displacement current density is neglected [1].

Magnetic vector potential is defined as,

(12)

Using eq(11.3),(11.4) & vector identity, magnetic vector potential of different domain of the

figure (2) can be written as,

Ω1, Ω4 (13.1)

Ω2 (13.2)

Ω3 (13.3)

Figure 2, 2D axisymmetric geometry of induction coil and workpiece

For 2D axisymmetric geometry and in cylindrical coordinate, eq (13.1) can be written as,

(14)

Here,

θ, z,r= Cylindrical coordinate




Aθ= θ Component of the magnetic vector potential (V.sec/m)

ω=Angular frequency (Rad/sec)

Finite element method (FEM) is used to solve the eq (14). FEM converts PDE into set of

algebraic equations in matrix [9] form as shown below,

(15)

Here, [K] = Stiffness matrix

[H]= Mass matrix

{A}= Magnetic vector Potential

{J}= Electrical current density

Eq (15) is solved by using suitable boundary conditions and forcing function. Once, magnetic

vector potential is determined, then other quantities such as coil and work piece equivalent

resistance, reactance, workpiece power, coil inductance, surface magnetic field etc are

computed.

Simulation

Simulation is done by using FEM based multiphysics software. Programming and simulation

are done in three steps i.e. preprocessing, processing and post processing [10], as shown in

the figure 3,

Geometry preparation

Materials and Their properties

Pre processing Boundary conditions and forcing function

Meshing

Processing Solution

Calculate other variables Post processing


7



Figure 3. Programming steps for simulation

2. MAIN RESULTS

Induction coil and workpiece dimensions and physical properties are given in table I and table

II respectively. These dimension and properties are used to calculate coil and workpiece

parameters both analytically and numerically. Table III gives the boundary condition and

forcing function used for solving equation (15) using FEM based multiphysics software,

Table-I. Workpiece dimension and properties

Sr. No. Work Piece Description

1. Material Graphite

2. Outer Diameter 160 mm

3. Height 180 mm

4. Electrical Conductivity at 2930K 1.42653X105 S/m

5. Electric permittivity 1

6. Magnetic permeability 1

Table-II Induction coil dimensions and properties

Sr.No. Induction coil Description

1. Material Copper

2. Inside diameter 215mm

3. Outside diameter 247mm

4. Height 200mm

5. Coil tube diameter 16mm

6. Coil tube thickness 2mm

7. No. of turn 9

8. Electrical conductivity at 2930K 5.8X107 S/m

9. Electric permittivity 1

10. Magnetic permeability 1

Table-III Boundary condition and forcing function




Sr.No. Boundary condition Description

1. Outer boundary A=0

2. Asymmetry axis

3 Induction coil current 770 A

Figure 4(a), shows the geometry used for the simulation. Trigular elements are used for

domain discretization. Mesh density is refined at the surface of induction coil and work piece,

because of skin effect as shown in figure 4 (b). Figure 4 (c) also shows that magnetic flux

density is maximum at surface of workpiece, and it decays towards the centre of the

workpiece.

Figure 4(a) geometry (b) Meshing (c) Magnetic flux density (Bz) at 5 kHz

Figure 5(a), (b), (c) and (d) show the comparison of induction coil and workpiece resistance,

reactance, inductance and power calculated by analytical and numerical methods at different

frequency. From figure (5), it is observed that Analytical and numerical results are in good

agreement. The difference between analytical and numerical results is due to assumptions taken in

analytical method to simplify the mathematical calculations. Following assumptions are taken in

analytical method,

Air gap magnetic flux is constant.


9



No end/edge effect.

Magnetic field and electric field on surface of work piece are assumed constant.

During induction heating simulation following points need to be remembered for minimization of

error:

Minimum size of elements in induction coil and workpiece shall be less than penetration

depth.

External domain size shall be more than 10 times of induction coil. Small External domain

creates more reluctance to the magnetic flux path and gives error in numerically calculated

coil and workpiece parameters.

Current is used as forcing function to accurately calculate the mmf generated by the

induction coil.

0 5 6 7 8 9 10 11 12 13 14 15 160.0

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Rea

cta

nce

eq(O

hm

)

Frequency(kHz)

Analytical

Numerical

0 4 6 8 10 12 14 160.00

0.04

0.05

0.06

0.07

0.08

0.09

0.10

Resi

stan

ce e

q(o

hm

)

Frequency(kHz)

Analytical

Numerical

(a) (b)




0 4 6 8 10 12 14 160

7.87.98.08.18.28.38.48.58.68.78.88.9

Ind

ucta

nce(µ

H)

Frequency(kHz)

Numerical

Analytical

0 4 6 8 10 12 14 160

20

30

40

50

Work

pie

ce p

ow

er(k

W)

Frequency(kHz)

Numerical

Analytical

(c) (d)

Figure 5 Comparison of analytical and numerical results (a) coil and workpiece equivalent

reactance, (b) coil and workpiece equivalent resistance (c) coil and workpiece equivalent

inductance, (d) work piece power

Figure (6) shows the induction coil and workpiece power calculated by analytical formulas at

different frequency. Figure (7) shows the voltage required in circular and rectangular induction

coil tube for same workpiece power. From figure (7), it is observed that, in rectangular coil tube,

less voltage is required compared to circular coil tube. This is due to the more coupling

between induction coil and workpiece in rectangular coil tube.

4 5 6 7 8 9 10 11 12 13 14 15 160

5

6

7

8

9

10

Coil power

Wo

rk

pie

ce p

ow

er(k

W)

Coil

pow

er(k

W)

Frequency(kHz)

0

25

30

35

40

45

50 Workpiece power

0 4 5 6 7 8 9 10 11 12 13 14 15 160

300

400

500

600

700

800

900

Co

il V

olt

ag

e (V

)

Frequency(kHz)

Circular coil tube

Rectangular coil tube

Figure (6). Coil and workpiece power, Figure (7). Coil voltage for circular and rectangular

coil tube,


11



3. CONCLUSIONS

Analytical and numerical validation of coil and workpiece parameters in induction heating

process was carried out successfully. Analytical results are in good agreement with numerical

results. This analysis can be used to design and optimize the induction coil for different

industrial application like forging, melting etc. This study also helps for tuning of induction coil

with high frequency power source.

4. REFERENCES

[1]. Valery Rudnev, Don loveless, Raymond Cook, Micah Black, “Handbook of Induction heating”,

INDUCTOHEAT,Inc., Madison Heights,Michigan,U.S.A.

[2]. E.J Davies and P.G. Simpson, Induction Heating Handbook. McGraw Hill, 1979.

[3]. Mark William Kennedy, Shahid Akhtar, Jon Arne Bakken,, Ragnhild E.Aune, “ Analytical and

FEM modeling of aluminum billet induction heating with experimental verification”, TMS( The

mineral, Metals & Materials Society),2012

[4]. Mark William Kennedy, Shahid Akhtar, Jon Arne Bakken,, Ragnhild E.Aune, “Review of Classical

Design Methods as applied to aluminum billet heating with induction coils”, EPD congress, San

Diego, California, February 27-March 3(2011),702-722.

[5]. Andrzej Krawczyk, John A. Tegopoulos, “Numerical modeling of eddy current,” Oxford science

publications, P-17.

[6].Lisiate Takau, Pat Bodger, “Low frequency modeling of induction heater using series equivalent

circuit, transformer equivalent circuit, and finite element analysis”, Australasian universities power

engineering conference, AUPEC 2013.Hobart,TAS, Australia,29 September-3 October 02013, p-1-6.

[7]. R.Baker, “Design & calculation of induction heating coil”, AIEE Trans, 57, (1957), 31-40.

[8]. C Chabodez, S Clain, R.Glardon,D, D Mari, J.Rappaz, M. Swierkosz, “Numerical modeling in

induction heating for axisymmetric geometries”, IEEE transactions on Magnetics.Vol33, No.1

January 1997, P 739-745.

[9]. Sheppard J.Salon,” Finite element analysis of electrical machine”, Springer international edition,

2009.

[10]. Ion Carstea, Daniela Carstea, Alexandru Adrian Carstea, “A domain decomposition approach

for coupled field in induction heating device,” 6th WEEAS international conference on system

science and simulation in engineering, Venice, Italy, November 21-23, 2007, P63-70

Proceedings of 6th National Conference on Multidisciplinary Research in Science & Engineering, MIT AOE

Alandi, Pune, 5-6 June 2015, pp.12-20, ISBN: 978-93-84648-83-1



GLYCIDYL METHACRYLATE-DIVINYL BENZENE

POLYMERIC ADSORBENTS FOR REMOVAL OF O-

CRESOL FROM AQUEOUS SOLUTION

V.A.TARANGE1, A.M.KOTHA2*, P R THAKUR3 1 Department of Chemical Engineering MITAoE Alandi (D) Pune 412105 2 Department of Engineering Sciences MITAoE Alandi (D) Pune 412105

3 Department of Chemistry SPPU Pune 411007

Abstract

Phenol & phenolic derivatives like o-cresol proves to be a toxic chemical in wastewater. Phenolic contaminants are found in wastewater of various industries such as petroleum refining, textiles, iron and steel manufacturing, paper and pulp manufacturing etc. It is very important to remove phenols and aromatic compounds from contaminated water before discharge into any natural water because of their toxicity to aquatic organisms and eventually to human beings. Majority of phenols & phenolic derivatives are toxic substances in the form of hazardous wastes and suspended carcinogens.

Conventional processes for removal of phenols from industrial waters includes extraction, adsorption on activated carbon, electrochemical techniques, bacterial and chemical oxidation etc. All of these methods suffer from serious shortcomings such as high costs, incompleteness of purification, low efficiency, and formation of hazardous by-products.

Alternative methods of removal of different phenols from waste water have been explored in the present investigation. Removal of phenol from aqueous solutions is being done by using porous, cross linked polymeric resins of high surface area and porosity. Several resins based glycidyl methacrylate cross linked with divinyl benzene are synthesized and have been used for adsorption of phenols like o-cresol from waste water.

Key Words: polymeric adsorbents, adsorption kinetics, Phenolic derivatives, waste water

treatment

1. INTRODUCTION

Phenol and its derivatives are contaminants found in the waste water generated by several

industries1,2 such as paper and pulp, textiles, plastic manufacturing plants ,synthetic rubbers,

Glycidyl methacrylate-Divinyl benzene polymeric adsorbents for removal of o-cresol from

aqueous solution

13



pharmaceuticals etc. Phenol concentration in the waste waters is known to range from 100 to

1000 mg/L to even 2-3 %3. Phenols are considered as prime pollutants as they are harmful at

even very low concentrations. It is therefore imperative to remove these contaminants before

discharge into natural water bodies due to their toxicity to aquatic environment and eventually to

human beings.

Conventional processes for the removal of phenols include biological degradation, chemical

oxidation, solvent extraction, incineration and many more. Adsorption methods4-,8 have also

been reported for removal of contaminants especially on activated carbons and other natural

adsorbents9-12.

Adsorption of phenol has proved to be one of the most effective techniques for removal of

phenols because of the its ease of operation, simplicity of design, regeneration and reusability

of the adsorbents for many cycles of phenol removal and no formation of harmful by products.

In comparison with conventional adsorbents, polymers are seen to be very effective due to the

fact that their porosity and surface area can be tailored and the polymers and also be easily

functionalized.

The objective of the current study was to synthesize novel polymeric adsorbents based on

glycidyl methacrylate (GMA) cross linked with Divinyl benzene (DVB) of varying porosity and

surface area for efficient removal of phenol.

2. MATERIALS AND METHODS

2.1. Materials

The monomers Glycidyl methacrylate and Divinyl benzene were obtained from Sisco Research

Laboratories, Mumbai and Aldrich Chemical Co respectively. Cyclohexanol was procured from

Loba Chemie, Mumbai and Azo bis (isobutyro nitrile) and Poly vinyl alcohol from Himedia

Laboratories.

2.2 Synthesis of polymeric adsorbents

14 V.A.Tarange, A.M.Kotha, P R Thakur



The porous GMA-DVB copolymers were synthesized by suspension polymerization by varying

the amount of cross linking monomer as described previously13. Three polymeric adsorbents

GD100, GD 150 and GD 200 were synthesized by varying the amount of cross linking

monomer, DVB.

2.3 Determination of adsorption capacity of the polymeric adsorbents

Batch adsorption experiments were carried out by contacting the polymeric adsorbent with o-

cresol of initial concentration of 4 mmol/L to reach equilibrium at 30 °C. 1 g of dry adsorbent was

added to 100mL solution of o-cresol. The solution was shaken continuously for 24 hours to

attain equilibrium. 2 mL aliquots were sampled from the flasks at regular time intervals to

determine the adsorption kinetics. The residual concentration of –cresol was determined by UV

spectrophotometer by measuring the adsorption of o-cresol solution at 271 nm.

3. RESULTS

The adsorption of o-cresol on the three polymers at 271 nm are presented in Figure 1

Figure 1: Adsorption of o-cresol on polymeric adsorbents GD 100, GD 150, GD 200

0

1

2

3

4

5

6

0 20 40 60 80

Am

ou

nt

Ad

sorb

ed

X 1

0-3

m

ol/

L

Time min

GD 100

GD 150

GD 2000

1

2

3

4

5

6

GD100 GD150 GD200

Am

ou

nt

O-C

reso

l Ad

sorb

ed

Adsorbents

10 min

20min

30min

60min


aqueous solution

15



It is seen that adsorption of o-cresol is rapid initially and becomes slower near equilibrium.

Almost complete adsorption of o-cresol takes place in the first 30 minutes in case of all three

adsorbents. The o-cresol adsorption capacity was found to be maximum on GD 200 as seen in

Figure 1b. After one hour of contact with the adsorbents the amount of o-cresol removed from

aqueous solution by GD 100, GD 150 and GD 200 was 96, 92 and 97 percent respectively.

Table 1 lists some characteristics of the polymeric adsorbents. The surface area and pore

volume measurements of the adsorbents are indicated. It can be seen that as the amount of

cross linking monomer in the polymer increases the surface area and pore volume are also

found to increase.

Adsorbent Surface Area

(m2/g)

Pore volume

(cm3/g)

GD100 173 0.24

GD150 199 0.30

GD200 301 0.35

Table 1: Surface area and pore volume values of the three adsorbents

The SEM micrographs in Figure 3 represent the porous beaded nature of the polymers.




Figure 3: SEM micrographs of the adsorbents a) GD 100 b) GD150 c) GD 200

Kinetic Studies

The adsorption dynamic curve of o-cresol onto GD 200 was studied at 303K. Kinetic models

were used to determine the rate of the adsorption process. Two kinetic models were used to

investigate the adsorption process i.e. pseudo first order and pseudo second order. Three

different initial concentrations of o-cresol were used.

0

0.000005

0.00001

0.000015

0.00002

0.000025

0.00003

0.000035

0 50 100 150

qe

mo

l /g

time in min

0

0.00001

0.00002

0.00003

0.00004

0.00005

0.00006

0.00007

0 100 200

q (

mo

l/g)

Time in min

q mol /g

0

0.00002

0.00004

0.00006

0.00008

0 50 100 150

q (

mo

l/g)

Time min

q(mol/g)versus t

q(mol/g)


aqueous solution

17



Figure 4: o-cresol adsorption kinetics onto GD 200 at initial concentration of a) 0.0002M b)

0.0004M and c) 0.0005M at 303 K

The figure 4 shows that equilibrium can be reached around 150 min for adsorption of o-cresol

onto GD 200 polymer. Both pseudo-first-order and pseudo-second-order kinetic models were

used to correlate the adsorption data. The pseudo first order kinetic equation can be expressed

as:

log (qe-q) = log qe – (k1/2.303) t

where ‘qe’ is the amount of solute adsorbed at equilibrium per unit mass of adsorbent, ‘q’ is the

amount of solute adsorbed at any given time ‘t’ and k1 is the rate constant. A plot of log (qe-q) is

made versus time t to give a straight line as shown in Figure 2.

The pseudo second order kinetic model is given as:

(t/q) = (1/k2qe2) + (t/qe)

where k2qe2 is known as initial sorption rate where ‘k2’ is rate constant. The plot of t/q versus t at

different adsorption parameters will give a linear relationship, which allows for computation of

‘qe’ and ‘k2’ as shown in Figure 3

The values of qe ,k1 and k2 are calculated from the slope and intercept of the curves

represented in Fig 2, Fig and Fig 4 for the three different initial concentrations of o-cresol

solutions. The values are shown in Table 2

y = -0.021x - 4.292R² = 0.848

-8

-6

-4

-2

0

0 50 100 150

log(q

e-q

)

time(min)

y = 27302x + 86884R² = 0.974

0.00E+00

1.00E+06

2.00E+06

3.00E+06

4.00E+06

0 50 100 150

t/q

time(min)




Figure 5: Curve for a ) Pseudo first order kinetic model b) second order kinetic model for initial

concentration 0.0002 M at 303 K

Figure 6: Curve for Curve for a ) Pseudo first order kinetic model b) second order kinetic model

for initial concentration 0.0004M at 303 K

Figure 7: Curve for a) Pseudo first order kinetic model b) second order kinetic model for initial

concentration 0.0005 M at 303 K

y = -0.004x -4.533

R² = 0.780-5.4

-5.2

-5

-4.8

-4.6

-4.4

-4.2

0 100 200

log(

qe

-q)

time (min)

Log(qe-q) versus t

Log(qe-q)

Linear (Log(qe-q))

y = 15644x + 21570

R² = 0.997

0

1000000

2000000

3000000

4000000

0 100 200

t/q

time (min)

t/q versus t

t/q

Linear (t/q)

y = -0.004x -

4.292R² = 0.873-5

-4.8

-4.6

-4.4

-4.2

-4

0 100 200

log(

qe

-q)

time(min)

Log(qe-q) versus t

Log(qe-q)

Linear (Log(qe-q))

y = 11935x + 26639

R² = 0.996

0

500000

1000000

1500000

2000000

2500000

0 100 200

t/q

time(min)

t/q versus t

t/q

Linear (t/q)


aqueous solution

19



Initial

concn

(M)

Pseudo first order kinetic model Pseudo second order kinetic

model

Experimental

values of qe(mol/g)

after 24 hours

qe(mol/g) k1(min-1) R2 qe(mol/g) k2(litre/

mol min)

R2

0.0002 5.105 x 10-5 0.04836 0.848 3.66 x 10-5 8592.07 0.974 2.8x 10-5

0.0004 2.93 x 10-5 0.00921 0.780 6.39 x 10-5 11346.0 0.997 6.7x10-5

0.0005 5.10 x 10-5 0.0092 0.873 8.37 x 10-5 5347.2 0.996 8.6x10-5

Table 3: Values of qe, k1& k2 for different initial concentrations of o-cresol

Thus, from the above results we see that the adsorption of o-cresol onto GD 200 can be

approximated more favorably by the pseudo second order model than the pseudo first order

model. Also, adsorption equilibrium is seen to be reached even with a contact time around 150

min.

4. CONCLUSION

From the current study we can conclude that o-cresol can be effectively removed from aqueous

phase by GD polymers. Out of the three polymeric adsorbents prepared, GD200 shows the best

performance with 96.76% removal, followed by GD100 with 96.5% removal and GD150 with

92% removal in 60 minutes respectively. Also, the pseudo second order kinetic model fits the

adsorption process reasonably.

REFERENCES

1. A Dabrowski, P.Podkoscielny, Z. Hubicki, Chemosphere, 58, 1049-1070, 2005




2. A.Y. Dursun, C.S. Kalayci, J. Hazard. Mater. B123, 151-157, 2005

3. L.Boyadzhiev, S. Alexandrova, Sep. Sci. Technol, 1992, 27, 1307 Adsorption techniques

4. Wang R.C.; Kuo, C. C.; Shyu, C.C. J.Chem Technol., Biotechnol. Bioeng. 1993, 41, 572

5. M. Ahmaruzzaman, D.K.Sharma, J.Colloid Interface Sci. 287, 14, 2005

6. M. Ahmaruzzaman, Adv.Colloid Interface Sci, 143,48, 2008

7. K. Babić, G.H.M. Driessen, A.G.J. van der Ham, A.B. de Haan, J. Chromatogr. A, 1142

(2007), pp. 84–92

8. M. Carmona, A De Lucas, J.L.Valverde, J.F.Rodriguez Chemical Engineering Journal

117,155-160, 2006

9. B.H.Hameed, A.A. Rahman, J. Hazard. Mater. 160,576,2008

10. O. Hamdaoui, E. Naffrechoux J. Hazard. Mater. 147, 381, 2007

11. O. Hamdaoui, E. Naffrechoux J. Hazard. Mater. 147, 401, 2007

12.S.Rengaraj, S.H.Moon, R.Sivabalan, B. Arabindoo, V.Murugesan J. Hazard. Mater. B89 185-

196, 2002

13. A.Kotha, C.R.Rajan, S.Ponrathnam and J.G.Shewale Reactive Polymers 28, 227,

1996.

Proceedings of 6th National Conference on Multidisciplinary Research in Science & Engineering, MIT AOE Alandi, Pune, 5-6 June 2015 ,pp.21-31, ISBN: 978-93-84648-83-1



SELECTIVE HARMONIC REDUCTION TECHNIQUE FOR A MULTILEVEL INVERTER USING OPTIMIZATION

APPROACH

MRS. SARIKA DINESH PATIL1, SUMANT G KADWANE 2 1Department of Electrical Engineering

Rajiv Gandhi College of Engineering & Research Nagpur, India

2Department of Electrical Engineering

Yeshwantrao Chavan College of Engineering Nagpur, India

Abstract

A generalized formulation of Selective Harmonic Elimination (SHE) PWM for Multilevel Inverter is recently formulated in literature which can eliminate a large number of lower order harmonics. Various methods for calculating the firing angles for SHE PWM are known and still research in this area is ongoing. This paper presents a MATLAB based approach for modeling and simulation method suitable for studying SHE methods for researchers to apply them in various applications. In this paper a cascaded 3-Phase, 7- Level, H-bridge Multilevel Inverter using MATLAB/Simulink blocks is presented as a systematic approach for developing the model. The primary contribution of this paper is that the Simulink model developed can also be extended for higher level inverter applications. The proposed Model can generate stepped voltage waveform and can be programmed for a wide range of modulation indices

Key Words: Flexible AC Transmission System, Multilevel Inverter, Power Electronics, Selective Harmonic Elimination, SPWM-Sinusoidal Pulse Width Modulation 1. INTRODUCTION

Recently Multilevel Inverters are widely used in many industrial applications, where the

requirement is medium voltage and high power. Multilevel Inverter has been widely used for

chemical, oil, and liquefied natural gas plants, water plants, marine propulsion, power generation,

energy transmission, and power-quality devices, FACTS Devices [1-3]. Cascaded H-bridge

converter topology is prominently used and particularly useful for renewable energy and

DSTATCOM applications [4-5], [9]. While in comparison with traditional two-level voltage source

inverters, multilevel inverters have several advantages. The main advantage of multilevel inverter

is that of its stepwise output voltage. This advantage results in higher power quality, lower

switching losses, higher voltage capability moreover it also reduces the cost with transformer less

system at the distribution side. It has low distortion, low dV/dt and can draw input current with very

low distortion, can generate smaller common mode voltage, thus reducing the stress in the motor

22 Mrs. Sarika Dinesh Patil, Sumant G Kadwa



bearings in motor applications, and also it can operate with a lower switching frequency. Desired

output can be obtained from multilevel inverter with several number of dc voltages as inputs. If the

number of levels is increased the output voltage and current waveform approaches to the

sinusoidal waveform. The different topologies, control strategies and modulation techniques used

for Multilevel inverters have been presented in [6-7]. Reference [8] elaborates the industrial

applications of multilevel inverter. Consequently the reduced switching methods with lower

computation cycles are investigated in [10].

The generalized formulation of Selective Harmonic Elimination of multilevel inverter is presented

in literature recently. Half wave symmetry SHE PWM formulation is presented in [11-14], which

describes the formulation of SHE problem based on lower harmonic elimination technique. The

generalized problem for SHE is presented in various papers and nonlinear equations with

advanced computing methods like genetic algorithm, particle swarm optimization, bee algorithm

and bacterial foraging [13-17]. These papers primarily focus on the method of solving the nonlinear

equations but not the exact formulation of SHE problem with MATLAB/Simulink. Reference [20]

gives the MATLAB/Simulink Model of a Single-phase Grid-Connected Photovoltaic System. While

in present paper attempts to formulate the in depth MATLAB/Simulink based simulation of SHE

problem that will help the new researchers to carry out the research for further investigating new

SHE algorithms by spending less time in modeling the SHE problem.

1 REVIEW OF GENERALIZED SHE FOR MULTILEVEL INVERTER

The A multilevel cascade inverter consists a number of H-bridge cells that are connected

in series per phase, and each module requires a separate DC source to generate voltage

levels at the output of inverter.

+Vdc In1, In4 ON

Vout = 0 In1, In3 ON (1)

-Vdc In 2, In3 ON

The switching inputs shown as Si, i=1 to 4 in the Fig. 1 allows obtaining output voltage as per

(1). The H-bridge cells are serially connected over AC outputs to obtain expanded phase voltage

levels and therefore, the total output level is the synthesize of cells output of each H-bridge.

Selective Harmonic Reduction Technique for a Multilevel Inverter using optimization approach

23



Cascade Multilevel Inverter (CMLI) is one of the most important topology in the family of multilevel

and multi pulse inverters

Fig.1 Cascaded H-Bridge Multilevel Inverter

It requires least number of components as compared to diode-clamped and flying

capacitors. The minimum number of levels and the voltage rating of the active devices (IGBTs,

GTOs, power MOSFETs, etc.) are inversely related to each other. More levels in the inverter will

lower the required voltage device rating of individual devices; or looking at it another way, a higher

voltage rating of the devices will enable a fewer minimum number of levels to be used. The

cascaded multilevel inverter consists of a number of H-bridge inverter units with separate dc

source for each unit and is connected in cascade or series as shown in Fig. 1.




Fig. 2 Output voltage waveform of 7-level Cascaded Multilevel Inverter

The output voltage levels as seen from Fig. 2 of each phase and each line voltage is given

by (2) and (3) respectively.

m = 2s + 1 (2)

Switching devices = 2(m-1) (3)

DC Bus capacitors = (m-1)/2

where ‘s’ is the number of bridges, ‘m’ is the number of levels. The ratio of DC voltage source

naturally affects the output levels of a cascade multilevel inverter. The Fourier series expansion of

the general multilevel stepped output voltage is given in (4), where n is the harmonic number of the

output voltage of inverter.

(4)

Where

The switching angles can be chosen to obtain minimum voltage harmonics. Normally, these

angles are chosen so as to cancel the predominant lower frequency harmonics. The major

difficulty for selective harmonic elimination methods, including the fundamental switching

frequency method and the Virtual Stage PWM method, is to solve the transcendental equations for

switching angles.

To satisfy fundamental voltage and to eliminate 5th and 7th harmonics, three nonlinear equations

are as follows.


25



(5)

(6)

(7)

These equations are nonlinear transcendental equations that can be solved by any iterative

method such as the Newton-Raphson method, using genetic algorithms and resultant theory. The

selective harmonic elimination method is also called fundamental switching frequency method

based on the harmonic elimination theory proposed in [18],[19]. This paper presents a multilevel

inverter model with mathematical model for SPWM modulator to minimize THD with

MATLAB/Simulink models as discussed in forthcoming sections.

2 DESCRIPTION OF MODEL FOR CASE STUDY OF 7-LEVEL INVERTER

The primary building blocks in MatLab can be divided into 3 subsystems namely: Reference

Generation, H Bridge Cell and Firing Circuit. The Reference sine wave is generated sine block with

120° displacement for each phase and amplitude as per the modulation index requirement. Fig. 3

shows the main H-bridge cell of one inverter used for implementation of the multilevel inverter. The

full bridge inverter module includes four power switches to form an H-bridge. The basic H

bridge block of inverter in MatLab is one of the fundamental block for building Multilevel cascaded

H bridge inverter.

A multilevel cascade inverter consists a number of H-bridge cells that are connected in

series per phase, and each module requires a separate DC source to generate voltage levels

at the output of inverter. MATLAB/Simulink Model is designed for Three Phase 7-Level Multilevel

Inverter with three different firing angles as θ1, θ2 and θ3.




Fig. 3 H- Bridge Subsystem

These constant values of firing angles are then compared with the sine wave through

comparator and given to gate pulses of respective switches (IGBT) in H- Bridge Model. For three

phase generation the angles are displaced by 120° in each phase. The corresponding system for

generating firing pulses is shown in Fig. 4. The dead band is not considered in this simulation

model and complementary pulse is fed to the upper and lower switches of each leg of H bridge

inverter. Here sine wave is compared with firing angle θ. We need to calculate the proper values

of θ for evaluating the SHE algorithm. The values of three firing angles are set as θ1 = 12.49o, θ2 =

25.78o and θ3 = 56.14o.

2

G2

1

G1

<=

Relational

Operator2

>=

Relational

Operator1

A

From1

A

From

2

In2

1

In1

Fig. 4 Subsystem for generating firing pulses

Fig. 5 Simulink Model for SHE for 7 level inverter

In Fig. 5 the H-Bridge blocks are connected in series to build a phase for seven level

multilevel inverter and three phases are build to form the entire three phase inverter. The

corresponding firing angles are generated through constants as per the values of θ. Total 3 H-

Bridges per phase are configured in subsystem. The input to the gate pulse of this H-Bridge is


27



given through input S1-S4. According to this, stepped waveform is obtained at the output side.

Although the simulation is carried out for 7-Level inverter the number of H-Bridge block can be

added to increase the level as per formula given in (2). The results of this scheme are presented in

section IV.

3 RESULTS

Fig.6 shows the PWM generated for 1-Phase of the multilevel

Inverter fed to each switch of respective H-Bridges connected in series. It is quite evident that

these PWMs combined together results into a 7-Level PWM pattern. The phase voltage of seven

level inverter as per the simulation explained in section 3. is shown in fig.7(a). The DC sources of

12V each are used in the H-Bridge blocks. The results show the step changes of 12V each and

resulting amplitude of V36 amplitude of the phase voltage. In consistent with these results the

magnitude of V72 appears in Line Voltages as shown in

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.20

0.5

1

Time, s

PW

M 1

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.20

0.5

1

Time, s

PW

M2

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.20

0.5

1

Time, s

PW

M3

Fig. 6 PWM Pulses for generating H bridge

Fig. 7(b). The different switching angles obtained for modulation index M=0.8 is shown in following

table.

SWITCHING ANGLES

M Switching angles

θ 1 θ 2 θ 3




0.

8 12.49°

2

5.78°

5

6.14°

Also these results are obtained through Newton Raphson algorithm taking initial guess from

Bee algorithm [16] . The results are very close to the results of Bee algorithm. Table I shows the

switching angle for modulation Index M = 0.8. Whereas Table II shows the contents of lower order

harmonics and % of THD .

% OF HARMONICS

M Harmonics

0.

8

h 3 h 5 h 7

THD

0.68%

0

.53%

0

.48%

1

2.51%

designed as per Bee algorithm taken from [16].The corresponding harmonics order in Bar

Graph and List is obtained in Fig.7(c).

0 0.05 0.1 0.15 0.2

-100

-50

0

50

100

Time, sec

Ph

ase

Vo

lta

ge

, V

0 0.05 0.1 0.15 0.2-40

-20

0

20

40

Time, sec

Lin

e V

olta

ge

, V

(a)

0 0.05 0.1 0.15 0.2-100

-50

0

50

100

Time, sec

Ph

ase

Vo

lta

ge

, V

0 0.05 0.1 0.15 0.2-40

-20

0

20

40

Time, sec

Lin

e V

olta

ge

, V

(b)


29



(c)

Fig. 7 (A) Phase Voltage (B) Line Voltage (C) Bar Graph of FFT Analysis

The results obtained from simulation of MATLAB/Simulink shows that the harmonic THD

contents are 12.51% for phase voltage and 9.45% in line voltage using SPWM modulator. The

third, fifth and seventh harmonics are within 1% tolerance. 9th harmonic shall be automatically

cancelled and other higher order harmonics can be eliminated by conventional filter. While it is to

be noted that the fundamental harmonic is preserved and selected order of harmonics are very

small which strongly confirms the validity of proposed system.

4 CONCLUSION

Simulation of Multilevel Inverter for three phase 7-Level inverter with SHE in

MATLAB/Simulink is presented as a systematic design approach. This simulation model is a

generalized attempt for understanding simulation of multilevel inverter and can be extended for

desired number of levels. This is particularly useful for understanding simulation of SHE for

researchers who wants to do research in optimization of firing angles. Proper control strategies for

switching of the multilevel inverters are used. Care must be taken while implementing the switching

strategies as it is vital in the desired operation of the inverters .The harmonic distortions present in

the load current and voltage waveforms were observed and calculated through FFT analysis tool in

MATLAB/Simulink to validate the results.

REFERENCES




[1] J. S. Lai, F. Z. Peng, Multilevel Converter-A New Breed of Power Converters, IEEE Trans.

Industry Applications, Vol. 32, No. 3, May/June 1996, pp. 509-517.

[2] L.M.Tolbert, F.Z.Peng, Multilevel Converters as a utility interface for renewable energy system,

IEEE conference, 2000 Vol.2,pp. 1271-1274.

[3] T.A. Meynard, H. Foch, P. Thomas, J. Courault, R. Jakob, and M. Nahrstaedt, Multicell

Converters: Basic concepts and Industry applications, IEEE Trans on Industrial Application, Vol.49,

No. 5, pp 955-964, Oct.2002.

[4] K. Corzine, Y. Familiant, A new cascaded multilevel H-bridge drive, IEEE Trans on Power

Electron., Vol. 17, No. 1, pp. 125–131, Jan. 2002.

[5] N. Farokhnia, S. H. Fathi, and H. R. Toodeji, Direct nonlinear control for individual DC voltage

balancing in cascaded multilevel DSTATCOM, in Proc. IEEE Int. Conf. EPECS, 2009, pp. 1–8.

[6] J. Rodriguez, J.S. lai, and F.Z. Peng, Multilevel Inverters: A Survey of topologies, controls , and

applications, IEEE Trans on Industrial Electronics, Vol. 49, No. 4, pp 724-738, Aug 2002.

[7] L.G. Franquelo, J. Rodriguez, J. I. Leon, S. Kouro, R. Portillio, and M.A. M. Prats, The age of

multilevel Converters arrives, IEEE Trans on Industrial Electronics., Mag, Vol.2, No. 2, pp 28-39,

June 2008.

[8] S.Kouro, M. Malinowski, K Gopakumar, J. Pou, L.G. Franquelo, Wu Bin,J Rodriguez, M.A

Perez, J.I.Leon, Recent Advances and IndustrialElectronics, Vol 57,

Issue: 8, Page(s): 2553 – 2580, 2010.

[9] Mariusz Malinowski, K. Gopakumar, Jose Rodriguez, Marcelo A. Perez, A Survey on

Cascaded Multilevel Inverters, IEEE Trans on Industrial Electronics., Vol. 57, No. 7, July 2010.

[10] Applications of Multilevel Converters, IEEE Trans on Industrial Electronics,

Vol 57 , Issue: 8, Page(s): 2553 – 2580, 2010.

http://ieeexplore.ieee.org/xpl/tocresult.jsp?isnumber=5508599



31



[11] L.G. Franquelo, J. Rodriguez, J. I. Leon, S. Kouro, R. Portillio, and M.A. M. Prats, The age of

multilevel Converters arrives, IEEE Trans on Industrial Electronics., Mag, Vol.2, No. 2, pp 28-

39, June 2008.

[12] S.Kouro, M. Malinowski, K Gopakumar, J. Pou, L.G. Franquelo, WuBin, J Rodriguez,

M.A Perez, J.I.Leon, Recent Advances and Industrial Applications of Multilevel Converters, IEEE

Trans on Industrial Electronics, Vol 57 , Issue: 8, Page(s): 2553 – 2580, 2010.

[13] Mariusz Malinowski, K. Gopakumar, Jose Rodriguez, Marcelo A.Perez, A Survey on

Cascaded Multilevel Inverters, IEEE Trans on Industrial Electronics., Vol. 57, No. 7, July 2010.

[14] Samir Kouro, Jaime Rebolledo, Jose Rodriguez, Reduced Switching-Frequency-

Modulation Algorithm for High-Power Multilevel Inverters, IEEE Transactions On Industrial

Electronics, Vol. 54, No. 5, October 2007.

[15] Mehrdad Tarafdar Hagh, Hassan Taghizadeh, Kaveh Razi,Harmonic Minimization in

Multilevel Inverters Using Modified Species-Based Particle Swarm Optimization, IEEE

Transactions On Power Electronics,Vol. 24, No. 10, October 2009.

[16] Ayoub Kavousi, Behrooz Vahidi, Reza Salehi, Mohammad Kazem Bakhshizadeh, Naeem

Farokhnia, S. Hamid Fathi, Application of the Bee Algorithm for Selective Harmonic Elimination

Strategy in Multilevel Inverters, IEEE Trans on Power Electronics, Vol. 27, No.4, APRIL 2012.

[17] R.N. Ray, D. Chatterjee, S.K. Goswami, Reduction of voltage harmonics using optimisation-

based combined approach, IET Power Electronics IET Power Electron., Vol. 3, Iss. 3, pp.334–

344,2010.

[18] H. S. Patel, R. G. Hoft, Generalized Harmonic Elimination and Voltage Control in Thyristor

Converters: Part I – harmonic elimination, IEEE Transactions on Industry Applications, vol. 9, pp.

310-317. May/June 1973.





[19] H. S. Patel, R. G. Hoft, Generalized Harmonic Elimination and Voltage Control in Thyristor

Converters: Part II –Voltage Control Technique, IEEE Transactions on Industry Applications, vol.

10, pp.666-673.Sept./Oct. 1974,

Proceedings of 6th National Conference on Multidisciplinary Research in Science & Engineering, MIT AOE Alandi, Pune, 5-6 June 2015, pp.32-36, ISBN: 978-93-84648-83-1



OPTIMISATION OF STOCKYARD LAYOUT IN CONCRETE PRODUCT INDUSTRY

V.S. JAGADALE, PROF. DR. P.G. GAIKWAD

Department of Civil Engineering, N.D.M.V.P‟s KBTCOE, Nashik

Abstract

The Concrete product manufacturing industry produce and supply different pre-cast products to the construction industry. Sales in the industry based on season; demand is more in summer than in other seasons. Site layout management is a complicated task which includes Products space requirement, different handling and storage requirements, Production unit area, and Seasonal demand of the products. For the industry to manage such Irregularity and maintain a constant production rate, stock is built in winter mostly and dispatched in summer. Due to wrong stocking of products in the stockyard, the industry undergoes space congestion for the storage and dispatch of products. During dispatch of products, it is very difficult to find the products location for loading into Lorries, long queues are formed of Lorries and required service is not possible to maintain. The problems is planning site layout which include Suitable design of stockyard space, road connectivity, production unit space, and curing area. Adequate layout examines the parameters which affects the loading and dispatch process in the stockyard and strategies to optimize the stockyard layout. The proper stockyard layout will reduce the throughput time of products.

Key Words: Precast Products, Site layout, Arrival and dispatch pattern, Space occupancy 1. INTRODUCTION

Site layout planning is most neglected aspect in construction industry and engineers generally think

it will be done with progress of work. Most construction sites are in trouble due to incorrect

managerial decisions rather than due to technical problems. The site-based management helps for

significant improvements in the time and cost savings in construction process without including

additional work. Precast concrete products are moved to storage after the production from the

plants. To achieve adequate strength, the minimum time of curing required is about four weeks.

Due to seasonal demand, the products produced during winter stay for 2-3 months on the

stockyard. The allocation of products at different places in the stockyard affects the time required

for storage and retrieval of products. Products arriving on site are off-loaded into different places

should be the correct location. This problem may cause double or triple handling of products to

another location.

Optimization of Stockyard Layout in Concrete Production Industry 33



The demand of products is different in each month depending on seasons; the industry accepts

“make-to-stock” production strategy. Through put time depends on location of products in

stockyard, the route followed by the lorry and number of resources present in stockyard for loading.

There are different products are produces and stored in the stockyard, the retrieval of products from

the various locations in stockyard is very difficult. The products produced first should be dispatched

first, and new products will occupy the resultant vacant space (not necessarily by the same type).[1]

The rotation of products to strategic locations, easy loading and dispatch process is necessary.

2. METHODOLOGY

In the present study information is collected from National cement Pipe Company situated in

Satpur, Nashik. There are different factors which affects the demand and supply pattern of

products. Study is done to find better results.

Lorrie‟s arrival pattern: Lorries arrive at unusual rates in service hours and their hourly arrival rates

are collected and graph is plotted.

Study site layout plan for existing vehicular routes, storage locations for different products. The

Annual demand and supply pattern of products is studied from collected data of year 2014 from

site. Clustering is done of group of concrete products that are frequently requested together, so that

the retrieval time of products to serve an order is minimised. One or more groups of products are

assigned to a storage location. Frequency analysis is done to identify the most frequent products

and allocate them in strategic locations on the stockyard. Study the space required for different

products and space occupancy chart of past year. The optimisation is to find the allocation of

products to different locations so that time and cost of storage and retrieval will be less and

efficiency of stockyard is will maximize.

3. ANALYSIS

Products are manufactured as per the production schedules and placed at different locations in the

stockyard. The delay of storage time can be removed by changing the allocation of products at

different locations.

Fig.1 Site layout plan of case study

34 V.S. Jagadale, Dr. P.G. Gaikwad



Arrival Rate- The rate at which Lorries arrive is served i.e. no. of Lorries arriving per hour is

calculated to study queuing time.

Service time for loading-

The service time for loading depends on the number of products and quantity to be loaded.

Frequency Rate-

The frequency analysis is done to find the frequently supplied products to allocate them at strategic

places in the stockyard. The analysis is done by grouping them based on frequency, such as

popular products (A), medium products (B), and less popular products(C). [3] The products which

have average frequency of more than one per day are classify as „A‟ class; which have frequency

less than one per day and greater than or equal to one per week were classify as B class products.

Similarly, the products having frequency less than one per week were classified as „C‟ class

products. [3] The graph of % products vs. % frequency is plotted from collected data and presented

in Figure 3.

Throughput time-

The time required for loading to complete specific order and queuing time on site is depending on

stockyard efficiency. The stockyard layout impacts to the throughput time i.e. time spent by a lorry

in the stockyard for loading.

Storage Space Utilization (SSU) ratio = storage space occupied / total available storage space.

4. RESULTS

Arrival rate is determined by collecting average number of Lorries arrived in the stockyard in total

working time monthly presented in fig.2

Fig.2 Arrival Rate- rate at which Lorries arrive

Frequency Rate-

The products which are analysed A class (22.6%) products constitute 84.3% of frequency; B class

(33.1%) constitute 11.1% frequency and C class (44.3%) constitute only 4.6% frequency.

Optimization of Stockyard Layout in Concrete Production Industry 35



Fig.3: Frequency rate of products supply

Space Occupancy Chart- The space requirement for products A, B and C is different in every

month depending upon demand and supply.

Fig. 4: Comparison of Variation in Storage Space Utilization for „A‟ Products

Throughput time- The time required for the loading by changing positions of products is different is

analysed and graph of average throughput time and required months is plotted in Fig. 5.

Fig 5: Variation on Average Throughput Time with different Assignment of Products to Storage

Locations.

36 V.S. Jagadale, Dr. P.G. Gaikwad



5. CONCLUSION

The throughput time required for the current layout is high hence improved layout is necessary. By

changing positions of products the required time for the supply can optimized up to 9-10%. The

Strategies is has be study to reduce throughput time in yard by Defining product locations such as

Fixing travel routes, increasing loading resources, just-in-time production strategy, considering

stockyard space availability, and Implementing appropriate communication system and so many

factors.

ACKNOWLEDGMENT

I am very grateful to these intellectuals who did their best to help me during our project work. The

special gratitude goes to Prof. Dr. P. G. Gaikwad, Head of Civil Engineering Department,

N.D.M.V.P‟S K.B.T.C.O.E. who guided me especially in paper presentation activities and to all the

staff members of the Civil Engineering Department for their precious suggestions and guidance in

completion of this work. I remain indebted to Prof. R. V. Devalkar, for their timely and valuable

suggestions and excellent guidance for completion of this work.

REFERENCES

[1] Ramesh Marasini, Nashwan Dawood, Stockyard layout management for precast concrete products using simulation, The Environment Section School of Science and Technology University of Teesside, Middleborough TS1 3BA, (2001)

[2] Nashwan Dawood and Ramesh Marasini, Optimization of stockyard layout for the pre-cast building products industry, !5th annual ARCOM Conference, Liverpool John Moores University (Sept. 1999)

[3] Ramesh Marasini and Nashwan Dawood, A simulation model to manage and optimize stockyard layout: A case study in precast concrete products industry, In: Akintoye, A (Ed.) 16th Annual ARCOM Conference, Glasgow Caledonian University. Association of researchers in Construction Management, Vol. 2, 527-36 (sept.2000)

[4] Nashwan Dawood and Ramesh Marasini, An integrated database for real-time management of stockyard “Stockman”: A case study in precast concrete products industry. The Environment Section School of Science and Technology University of Teesside Middleborough TS1 3BA (2001)

[5] Arash Shahin, Mehdi Poormostafa, Facility Layout Simulation and Optimization: an Integration of Advanced Quality and Decision Making Tools and Techniques8. (May 29, 2011)

[6] Ramesh Marasini and Nashwan Dawood, Integration of genetic algorithms and simulation for stockyard layout planning. 18th Annual ARCOM Conference. Association of Researchers in Construction Management, Vol. 2, 821-30(Sept.2002)

[7] Ammar Al-Bazi, Nashwan Dawood, Enterprise simulation of the precast manufacturing industry, International conference on Information Technology in Construction. (2008)




A SURVEY ON LINK PREDICTION USING TEMPORAL APPROACH

ANDHARE VIPUL, MAHAJAN PRATHAMESH, PANZADE AMOL, JOSHI

APURV Department of Information Technology, MIT Academy of Engineering, Alandi (D),

Pune, India

Abstract

In recent year link prediction considered as main area of research in social network. A link is predicated based on structural and temporal aspect of the social network. Feature vector used for predicting the links between the nodes of social graph. Many researchers proposed feature vector based on structural data of social graph. As the evaluation in internet web technology social network grows exponentially there for predicting accurate link structural data of social graph is not sufficient some temporal data of social graph such as no. of interaction is used to proposed temporal feature vector by many author. A survey on temporal feature vector is present in this paper.

Key Words: Link prediction, Feature vector, collaborative networks, structural and temporal link prediction, global and local similarity indices 1. INTRODUCTION

Social networks are those collaborating networks which are formed with the interaction between

autonomous entities and which leads to achieve common compatible goal and the strength of

interaction among the nodes is used to predict the future links. It is possible to represent

biological, social and information systems using such networks where nodes are represented by

entities of system and edges represents collaboration among them [1]. Further these edges can

be adorned with consideration of added information like time stamps and weights. Efforts taken

on estimation of possibility of presence of link between two nodes depending on observations of

known links and their features are known as link prediction.

Link prediction can be done by two types: (1) Structural, where a portion of graph is considered

for observation so that remaining possible collaborations between nodes can be predicted and

(2) Temporal, in which graph is observed at several time steps with the goal of predicting graph

38 Andhare Vipul, Mahajan Prathamesh, Panzade Amol, Joshi Apurv



state at next time step [2]. As exploiting information of pattern of interaction is possible with

different approaches of temporal link prediction, it may be considered as more significant [3].

Both of link prediction types have practical applications which made it as important task in

network science however the challenges of complexities emerging in extensive real world

networks can be handled more optimistically [4]. Social network users are recommended for

possible interactions, applications like criminal investigations, Researchers can find other

individuals who are working in same domain.

In next section we have discussed concept of feature vectors, both structural and temporal

types.

2. FEATURE VECTOR

When to consider a huge dataset of social network, to predict the links which may or may not

form in future, it can represented as nodes and edges of graph and various graph attributes like

common neighbour, shortest path etc. for every pair of node can be calculated.

Various studies proposed feature vectors on the basis of structural data of social network but

since the data of networks is increasing very rapidly these methods are considered to be

inefficient to handle the dynamics of the network. Thus, some researchers proposed methods to

form temporal feature vectors using data of network at time t. In the temporal methods, the

current dataset is used which may vary with respect to time such as no. of interactions, degree

of nodes.

3. FEATURE VECTORS BASED ON STRUCTURAL ATTRIBUTES OF GRAPH

In structural types where nodes (ni, nj) represent individuals, edges (eij) represent relationship

among them. These node and edges can be represented as a graph. For every pair of node we

can calculate various graph attribute (viz. shorted path and common neighbour) which when

associated with the probability of appearing links in future, a feature vector is generated.

1) Local Similarity Indices: Local feature measured only the nodes attribute of the network and

the global feature uses all the paths in the network. Linyuan Lu and Tao Zhou [1] categorized

the locally-based similarity indices which are node-dependent such as Common Neighbours,

Adamic/Adar index, Jaccard‟s Coefficient, etc. are used to analyse the existence of a link in a

network based on proximity of nodes. As shown in table [Table I].

2) Global Similarity Indices: Global features consider complete graph information, for predicting

the existence of a link. They provide more efficient link prediction than local features. The

A Survey on Link Prediction Using Temporal Approach 39



global-based approaches i.e. KATZ status index, RWR algorithm, Sim-Rank algorithm, etc. are

path based approach. As shown in table [Table II].

TABLE I

METHODS OF LOCAL SIMILARITY

Sr .No Method Name Description Formula

1 Common neighbor

Common neighbor is the

method for which we can

find the common node

between predicate nodes

= |�(x) ∩ �(y)|

2

Adamic – Adar[11]

Index

This index refines the easy

including of common

neighbors by conveying the

less-connected neighbors

more weight.

3 Jaccard's

coefficient

It is define as the size of

fork of the neighbor Of two

nodes [12].

TABLE III

METHODS OF GLOBAL SIMILARITY

Sr.No Method Name Description Formula

1 Katz Index[12]

This index is based on

resemble of all paths,

which directly

Summation over all

possible paths.

2 Shortest path

distance[13]

In social network the

arrangement of links

between the two nodes




is based on the path

distance between them.

---

3 Sim

Rank[13]

If two objects are

referenced by similar

objects, then they are

said to be similar. This

is defined by simrank

generic metrics

4. FEATURE VECTORS BASED ON TEMPORAL ATTRIBUTES OF GRAPH

The majority work in link prediction is performed by considering various states of the network to

predict the new links, but not considering the time as a constraint. While in time aware link

prediction, time is considered as one factor and other attributes are also applied resulting in

construction of a time weighted network.

Time stamps are built for each link formation and computing scores at different past times. Time

score is used to capture the important aspects of time stamps. Effectiveness of time score

varies for different network datasets and different time measures. If the two common neighbor

nodes have interacted in a specific period of time, then the time stamp for their link has higher

value and the links related to them which are not linked have higher probability of linking in

future than the common neighbors having links with lower time stamps.

In a dynamic social collaborative network, the formation of new links indicate the interaction

among nodes has started. The strength/weakness of the link is dependent on the frequency of

interaction.

Time varying social networks can be used to model groups whose dynamics change over time.

Individuals, represented by nodes, may enter or exit the network, while interactions, represented

by links, may strengthen or weaken.

Traditional collaborative network analysis techniques such as co authorship model and social

network model which often collect the data from a huge network statically. But in the temporal

network, we consider the data on time basis. The weights given to the links and the ranks given

to nodes change by the period of time. The feature vectors are formed temporarily and with

context of time the prediction is done [14].




Fig. 1 Snapshot of the graph before prediction Snapshot of the graph after formation

of links

The user data available in social network consists of relationships which will be represented as

a link between them. Here the temporal link prediction is considered on time, i.e. the dynamics

of the network graph changes according to time. In other words we can say that the association

or links between the node pair becomes weak when they are not interacting with the each other

for a long time with respect to current time. The weight of links is given by the time they have

interacted. If two users have interacted with their common neighbours, then the probability of

them being linked in future is high. In the temporal link prediction, we analyse the static graphs

of the network taken at different time intervals. In fig 1 we have taken a snapshot of a network at

some instance. The nodes are the users of the network and the date of generation of the link is

given on the edges. The node Eva interacted with the neighbours Alies and John, so the link

between Alies and John is formed. Similarly, link between Eva and Bob is formed using the

temporal behaviour of the network. In the fig 2, the snapshot of the static graph of the network is

shown.

TABLE IIIII

METHODS OF TEMPORAL TYPES




5. SURVEY Lankeshwara Muna Singh and Ryutaro Ichise proposed new technique of time aware index for

link prediction in social network [5]. Time stamp of interaction is the main part for the evaluation

of link. The new idea which focuses on the temporal link strength and time stamp and examines

the temporal type of prediction on the two data sets is proposed.

In [6] XiongcaiCai, Michael Bain, Alfred Krzywicki, Wayne Wobcke , Yang Sok Kim, Paul

Compton, and AsheshMahidadia consider the heterogeneous and reciprocal link prediction

problem and proposed a framework to address prediction of the sign of a link in heterogeneous

and reciprocal networks. Link prediction is defined as the inference of new interactions among

the members of a given social network.

Sr.No Method

Name

Description Formula

1 Vector Auto

Regressive

(VAR)

Method[14]

It is “baseline” method, which

generalizes the univariate

auto-regressive (AR) model to

multiple time-series.

~Xt ≈ At−1 · ~Xt−1 + ... + At−T ·

~Xt−T

2 The Lasso

Granger

Method

The Lasso algorithm for linear

regression is an incremental.

Algorithm that embodies a

method of variable selection

using the L1-penalty term.

w = arg min 1 n X (~x,y)∈S |~w ·

~x − y|2 + λ||~w||1

3 Time-aware

Maximum

Entropy[23]

This time-aware method works

by allowing to forget old

events, thus minimizing noise

which they might initiate.

wjlj ( )

4 Time

Score[5]

The vital aspects of time

stamps of interactions and the

temporality of the link

strengths. Time scorewhich is

basically assigned a weight for

future possible links.

S




SuchetaSoundarajan, John E. Hopcroft presented the various methods for link prediction [7] and

shown enhanced local similarity metrics often outperform their associated base metrics. Though

no single metric was best for every network, they showed that one can perform cross-validation

or compare metric values for existing pairs of connected and un-connected nodes to determine

whether a particular method is likely to succeed on a given network. A related problem is that of

determining which base local similarity metric is best for a particular network.

In [8] new temporal distance metrics to quantify and compare the speed (delay) of information

diffusion processes taking into account the evolution of a network from a local and global view.

Analyzing how varying the window size aspects the temporal metrics. It is inversely proportional

to the temporal path length, temporal efficiency decreases as the window size increases.

Supervised Random Walks, a new learning algorithm for link prediction and link

recommendation is proposed in [9]. This approach requires no network feature generation and

in a principled way combines rich node and edge features with the structure of the network to

make reliable predictions. Supervised Random Walks are not limited to link prediction, and can

be applied to many other problems that require learning to rank nodes in a graph.

Daniel M. Dunlavy and Tamara G. Kolda considered bipartite graphs that evolve over time and

consider matrix and tensor-based methods for predicting future links [10] and presented a

weight-based method for collapsing multiyear data into a single matrix. They examine how the

well-known Katz method for link prediction can be extended to bipartite graphs and, moreover,

approximated in a scalable way using truncated singular value decomposition. Despite the high

level of noise, the CP method is able to get an AUC score of 0.845, which is much better than

then the “Last Period” method‟s score of 0.686. Daniel M. Dunlavy and Tamara G. Kolda also

considered the accuracy in the first 1,000 values returned. The CP-based method is 100%

accurate in its top 1,000 scores whereas the “Last Period” method is only 70% accurate.

Approach of solving link prediction problem using supervised matrix factorization is proposed by

Aditya Krishna Menon and Charles Elkan with better efficiency. By analysing existing link

prediction models authors suggested new mechanism to overcome problem of imbalance in

factorisation. Comparison between proposed model and other link prediction models is also

given [2].

Conrad Lee, Bobo Nick, UlrikBrandes and Pádraig Cunningham suggested features based on

social vector clocks which exploits different aspects of link formation [3]. Dataset of twitter is

considered to evaluate performance of vector clock link predictor (VLCP). Understanding of

actual mechanism behind link formation is focused in article [3].




JeyanthiNarasimhanand Lawrence Holder given two step solution for link prediction in dynamic

networks. Feature construction approach with combination of domain and topological attributes

and edge selection learner are the two phases proposed. The problem of rank deficient Time

Feature matrix is not covered in article [16].

Complex network structures of evolving networks where nodes and links are added and

removed over time. A precise challenge is the description and explanation of dynamics network,

with a key test being the prediction of short and long term changes. For the problem of short-

term link prediction, existing methods attempt to decide neighborhood metrics that associate

with the form of a link in the next observation period. Recent search recommended that the

integration of topological features and node attributes can improve link prediction. [1] In this

paper, primary focus is on the link prediction problem and local information and use similarity

indices to distinguish the probability of future interactions are also focused. They considered the

two main classes of similarity indices: topological-based and node attribute.

Link Prediction techniques often focus on global properties or local properties. Abir De,

NiloyGanguly, SoumenChakrabarti they have describe a discriminative Link Prediction algorithm

that exploits two new signals First, a co-clustering algorithm provides community level link

density estimates, Second, links in the instant neighbourhood of the link to be predicted are not

interpreted at face value[11]. The evaluation of the new predictor using five different data sets

that are standard in the literature is done and new two-level learning algorithm for link prediction

is described. In the future the combination of the signals with supervised personalized

PageRank can be done. Another opportunity to replace item-wise or pair wise losses with list-

wise losses suitably aggregated over query samples.

Dashun Wang, Dino Pedreschi, Chaoming Song, Fosca Giannotti1, Albert-LászlóBarabási find

that the similarity between two those movements strongly correlates with their closeness in the

social network and explore how the predictive power hidden in such correlations can be broken

to address a challenging problem: which new links will develop in a social network. Mobility

procedures on your own predictive power, similar to traditional network-based measures. In this

work, they follow the trajectories and communication. Patterns of approximately 6 Million users

over three months, by using CDR data from an anonymous country, aiming to measure for any

pair of users [12]. They improvement in link prediction tasks by thoughtfully assimilation mobility

and network measures.

In the online social networks, the new links are formed among the users which have some

friends in common. There are two types of approaches to predict the links viz. local based and

global based. Normally the depth considered for local similarity index is maximum 2, but in [18],




the authors have suggested to use depth more than 2. The method was more efficient for the

network as compared to the global approach. They designed their algorithm „FriendLink‟ for

signed and unsigned networks. Although the interactions like commenting and tagging are not

considered in their work.

The main challenge in data mining is to find the result for the query from a structured or an

unstructured datasets, in which the objects are linked to each other. The patterns of links are

very helpful in link mining. These datasets are generally multi-relational, semi structured or

relational databases. LiseGetoor in his paper [19], subcategorized the link mining tasks into

three types viz. Web page collection, Bibliographic domain and Epidemiological Studies. Mainly

6 challenges faced during the link prediction are discussed.

[20] Examines the main factors for link prediction in a collaborative network and provides a new

perspective and methods for prediction of the future links. The comparison between supervised

and unsupervised algorithms is done and the techniques for evaluation of the data are

discussed.

Andrew Arnold, Yan Liu and Naoki Abe proposed a systematic evaluation of the relative

performance of a host of related methods of temporal causal modelling based on Granger

causality and graphical modelling [21]. As shown in [21] the definition of Granger Causality is a

notion of causality that is highly relevant to the present context of temporal causal modelling

called “Granger Causality”. The present paper proposed that upto what extent temporal

information present in time series data can assist in the modelling and understanding of the

causal structures between time-persistent features, rather than temporal variables.

As Ben Taskar, Ming-Fai Wong, Pieter Abbeel and Daphne Koller shown that the use of a

probabilistic model over link graphs allows us to represent and exploit interesting subgraph

patterns in the link graph, these methods have been applied to the problem of predicting or

classifying a single link at a time. As shown in [22] that the problem of modeling link graphs has

numerous other applications, including: analyzing communities of people and hierarchical

structure of organizations, identifying people or objects that play certain key roles, predicting

current and future interactions, and more.

6. CONCLUSIONS

In this survey paper, we have reviewed several current papers on link prediction, temporal

graphs and time aware link prediction. The link prediction problems can be solved using various

algorithms present but one thing is noticed is that the problem which can be solved by one

algorithm need not be solved up to that extent by other algorithm. The time aware link prediction




is done on the temporary data sets and the process of link prediction is different than the static

link prediction done on the static network.

REFERENCES

1. Linyuan Lu and Tao Zhou. Link Prediction in Complex Networks: A Survey. Elsevier Science 2010.

2. Aditya Krishna Menon and Charles Elkan. Link Prediction via Matrix Factorization. 2011. 3. Conrad Lee, Bobo Nick, UlrikBrandes and Pádraig Cunningham.: Link Prediction with

Social Vector Clock 2013. 4. Mohammad Al Hasan, VineetChaoji, Saeed Salem, and Mohammed ZakiLinkPrediction

using Supervised Learning Rensselaer Polytechnic Institute, Troy. 5. LankeshwaraMunasinghe and Ryutaro IchiseTime Aware Index for Link Prediction in

Social Networks. 6. XiongcaiCai, Michael Bain, Alfred Krzywicki, Wayne Wobcke , Yang Sok Kim, Paul

Compton, and AsheshMahidadiaReciprocal and Heterogeneous Link Prediction in Social Networks.

7. SuchetaSoundarajan, John E. HopcroftUsing Community Information to Improve the Precision of Link Prediction Methods.

8. V.Kostakos. Temporal Graphs. Physica A, 388 (6):1007{1023} 2009. 9. Lars Backstrom, Jure Leskovec: Supervised Random Walks Predicting and

Recommending Links in Social Networks. 10. Daniel M. Dunlavy and Tamara G. KoldaTemporal Link Prediction Using Matrix and

Tensor Factorizations ACM Transactions on Knowledge Discovery from Data. 11. Catherine A. Bliss, Morgan R. Frank, Christopher M. Danforth, Peter Sheridan DoddsAn

Evolutionary Algorithm Approach to Link Prediction in Dynamic Social Networks 12. Dashun Wang, Dino Pedreschi, Chaoming Song, Fosca Giannotti1, Albert-

LászlóBarabási: Human Mobility, Social Ties, and Link Prediction. 13. Pankaj Choudhary, Nishchol Mishra, Sanjeev Sharma A Survey on Link Prediction with

or without Time aware feature in Social Network. 14. Andrew Arnold Temporal Causal Modeling with Graphical Granger Methods. 15. Joshua O‟Madadhain, Jon Hutchins Prediction and Ranking Algorithms for Event-Based

Network Data. 16. JeyanthiNarasimhan and Lawrence Holder Feature Engineering for Supervised Link

Prediction on Dynamic Social Networks 2014. 17. Abir De, NiloyGanguly, SoumenChakrabartiDiscriminative Link Prediction using Local

Links,Node Features and Community Structure 2013. 18. Alexis Papadimitriou, Panagiotis Symeonidis, YannisManolopoulosFast and Accurate

Link Prediction in Social Networking Systems 2010 19. LiseGetoorLink Mining: A New Data Mining Challenge 20. Ryan N. Lichtenwalter, Jake T. Lussier,Nitesh V. Chawla New Perspectives and

Methods in Link Prediction. 2010. 21. Andrew Arnold, Yan Liu, Naoki Abe Temporal Causal Modeling with Graphical Granger

Methods 2007

22. Ben Taskar, Ming-Fai Wong, Pieter Abbeel, Daphne KollerLink Prediction in Relational Data




ISSUES OF PERSONS WITH DISABILITIES AND ACCESSIBILITY STANDARDS

IMPLEMENTATION

DHANANJAY BHOLE Coordinator, Accessibility Research Group and ATBSLC,

Department of Education and Extension, University of Pune Recipient of National Role Model Award by President of India for Empowerment of Persons with

Disabilities in 2011

The Constitution of India unequivocally expresses its commitment to secure justice; liberty;

equality; and fraternity to all its citizens. The list of fundamental rights enumerated in the

Constitution guarantees among other provisions, access to equal opportunities of participation

in socio-economic and political processes to all, without exception arising on account of any

discrete individual or group identity. Citizens with disabilities are an essential part of human

diversity an all-encompassing welfare state bears the obligation to be accommodative of and

sensitive to their circumstances and requirements.

In a resounding acknowledgement of this obligation, India has ratified the UN Convention on the

Rights of Persons with Disabilities (UN CRPD) and endeavored to ensure and promote the full

realization of all human rights and fundamental freedoms for all Persons with Disabilities without

discrimination on the basis of disability. In fulfillment of this international commitment a revised

version of Rights of Persons with Disabilities Bill is being proposed to align national laws in

conformity with the international laws, which seeks to ensure furtherance of the rights

recognized in the UN CRPD.

Approximately 6% of the world’s population has certain kind of disabilities; 9% percent of world’s

total population of persons with disabilities lives in India. India is the home of largest number of

visually impaired people (15 million). In Indian society, there are innumerable obstacles and

48 Dhananjay Bhole



barriers that hinder persons with disabilities; these include among other issues, accessibility to

buildings environment, transportation, information and communications, which makes it

impossible for persons with disabilities to take part in the life of a community. Education,

employment and other community services are not fully reachable to the larger section of the

disabled population in India despite existence of various standards, guidelines, policies,

directives and laws.

Several government, non government and corporate organizations are working towards

betterment of persons with disabilities in their own pace and ways. But they fail to provide

accessible environment to the persons with disabilities due to the lack of proper approach of

government and public representatives for implementation of standards and guidelines. Public

places like roads, foot paths, traffic lights, cross walks, railway stations, airports, bus stands,

government office premises, corridors, stare cases etc is inaccessible for persons with

disabilities including visually impaired as well as wheel chair users. Braille signs or audio signs

are not available at most of the public access places like railway time table, elevators, etc.

Educational institutions also hardly provide their programs, services and activities accessible

and usable for persons with disabilities. Course curriculum, teaching methodology, examination

and evaluation systems are not available in electronic and accessible format. Web services of

government, corporate and non government organizations are also hardly accessibility-

compliant. Persons with visual disabilities cannot book their railway or air ticket on web, cannot

use online banking facilities and cannot do online shopping independently and without difficulty

inspite of availability of advanced assistive technology tools like screen readers, screen

magnifiers etc. because of accessibility barriers in these web services. Public web services are

not designed considering users with disabilities so that they can enjoy barrier free environment.

Life of persons with disabilities is so dependent on others and mercy of government in our

country that they never get feeling of living in an independent nation.

I would like to bring attention of all the stake holders such as government, non government and

corporate organization towards inaccessible environment for persons with disabilities through

this white paper. As a researcher in this area found that most of the facilities can be improved in

the city which will provide better life to persons with visual impairment if taken on priority.Such

as:

Issues of Persons with Disabilities and Accessibility Standards Implementation 49



Foot paths, government buildings and traffic lights should be made accessible and all new

projects should be compliant with the accessibility guidelines given by ministry of urban

development.

BRT corridors should be demolished and new projects of BRT tracks should be canceled

because of its inconvenience.

City buses should be provided a kit that will announce bus stops and the staff should be

sensitized on the need of individuals with visual disabilities.

Public websitesof the Maharashtra state should be made accessible for persons with

disabilities as per any national or international accessibility standard or guidelines.

Educational institutions should be made obligatory to provide accessible services to persons

with disabilities such as accessible building infrastructure, website and other IT services

accessible.

Courses like web accessibility and accessible computing etc should be included in the

curriculum of Engineering, MCA, and M.Sc. degree programs. Also courses like building and

other civil constructional accessibility should be included in civil engineering, architectural

and design degree programs.

Banks, posts and government offices services should be made accessible and usable for

persons with disabilities such as internet banking software; core banking software postal

websites and IT services, e-governance services etc should be made accessibility

compliant.

Given the opportunities to them, persons with disabilities have proved that they are no less

competent or able than normal people. The office of the Commissioner of disability welfare can

undertake following few stapes for accessibility standards implementation:

The office can enquire the status of implementation and adaptation of accessibility

standards and guidelines in schools, secondary and higher secondary boards, colleges,

universities, banks, post offices, municipal corporations, district head quarters and other

government and corporate organizations and ensure proper compliance.

The office should direct all government and corporate organization to implement

accessibility standards and work toward making barrier free environment in a targeted

manner; e.g. they should be given 6 to 9 months for accessibility standard adaptation and

the organization should be asked to submit a report on efforts taken by the organization for

accessibility implementation and making barrier free environment.

50 Dhananjay Bhole



This will also help to implement UNCRPD and PMO’s directives and PWD act and other

policies. Several issues of Persons with disabilities will be resolved due to provision of

barrier free environment to them and they will no longer be burden on the government.

Persons with disabilities not only get equal opportunities but also their productivity will be

increased and they will contribute in the nation development.




COST EFFECTIVE STREET LIGHTS MONITORING SYSTEM (CESMOS)

ISHWAR KHUSPE 1, DR. M. V. BHATKAR 2

1 Final year M.E. Electrical (Power System), A.C. Patil College of Engineering, Kharghar, Navi Mumbai, Mumbai University,

2 Ph.D. IIT Bombay, Principal, Jawahar Education Society’s, Institute Of Technology, Management & Research, Nashik, Pune University

Abstract

Provision of good rather best street lighting is a prime duty of every local civic authority to create confidence and safety amongst its citizens. It requires huge funds for new installations and subsequently maintaining the same. Apart from street lighting local authorities have more important functions to be performed, such as drinking water, sanitation, health and clean environment. Always, it is a daunting task of a cash starved municipality to provide facilities to its citizens. Currently, around forty percent expenses are spent by local civic bodies towards payment of power tariff and maintaining the street lighting. During day time, street light routine maintenance causes huge wastage of electrical power. At present various methods are used for monitoring street lights, spanning from manual on-off control to advanced intelligent monitoring system. Because paucity of funds, civic authorities are reluctant to install capital intensive intelligent street light monitoring systems. Besides this, all present street light monitoring systems uses electronic hardware and interfaces. This creates enormous quantity of hazardous electronic waste. The disposal of such e-waste adds to the burden on civic bodies. Intra wireless communication between street lights and segment monitor creates unnecessary electromagnetic pollution. This is a project work on an innovative cost effective technique to monitor street lights, which will drastically reduce the cost of present street light monitoring system. It will completely eliminate the electrical power waste during routine maintenance of street lighting. Further it will reduce the e-waste, and electromagnetic pollution which helps in creating safer, cleaner environment to future generations.

Key Words: Street lights, monitoring, e-waste, electromagnetic pollution.

1. INTRODUCTION

Providing street lighting is one the most important and expensive responsibilities of a city. Street

lighting is a particularly critical concern for public authorities in developing countries because of its

strategic importance for economic and social stability. Inefficient lighting and absence of proper

monitoring systems, causes significant waste of financial resources each year. Inadequate lighting

creates unsafe conditions to the citizens too. Energy efficient technologies and design can cut

street lighting costs dramatically (often by 25-60%). These cost savings can enable municipalities

to expand street lighting to additional areas, increasing access to lighting in low-income and other

under privileged areas. Any improvements, in lighting quality and monitoring systems, can improve

safety conditions for both vehicle traffic and pedestrians. In India and developing countries, it is

52 Ishwar Khuspe, M.V. Bhatkar



quite often, street lighting is poorly designed and inadequately maintained. Thus, consumes large

amount of energy and financial resources.

India and South Asian countries are amongst the fastest growing regions in the world. Fast

growing population, urbanization and industrialization create extra pressure on civic bodies to

provide basic facilities. These local civic bodies are always having shortage of funds to provide

essential services to its citizens. The highly sophisticated street light monitoring systems require

hefty funds. Present, street lighting systems without any monitoring, requires hours of maintenance

keeping all street lights burning. This non efficient method of maintenance, leads to huge amount

of loss of electricity.

1.1. ENVIRONMENTAL DEMANDS It is especially important to the responsible local municipal authorities to implement the energy

saving potential in street lighting by upgrading the technology of their installations. While adopting

new technology they have to adhere, current regulations in force. Regulations regarding lighting

levels, electrical safety, electro-magnetic radiation (EMR), disposing electronics waste and

emission of greenhouse gases are strictly to be observed. The regulations regarding reduced use

of electronic components and its disposal have to be strictly followed and practiced. So that norms

which are set by international/local environmental laws, are met and collectively we can

accomplish environmental demands which are the need of the hour.

1.2. LITERATURE REVIEW

To get the insight of the research work in the various fields such as bad effects of EMR, electronic

waste disposal and street light monitoring system, following published literature were reviewed.

U.S. Food and Drug Administration (FDA) [1], defines the laws and regulations pertaining to

Electromagnetic radiation (EMR)-emitting products. It defines, any product which works on

electricity emits electromagnetic radiation.,

Paolo Vecchia, Rüdiger Matthes, Gunde Ziegelberger James Lin, Richard Saunders, Anthony

Swerdlow [2], discussed, the health issues pertaining to exposure to high frequency

electromagnetic field.

J. D. Lee, K.Y. Nam, S.H. Jeong, S.B. Choi, H.S. Ryoo, D.K. Kim [3], elaborated, on the

development of ZigBee based street light control system. This control cum monitoring systems

uses ,the ZigBee based communication protocol (2.4GHz) , the main emphasis were on to reduce

uneasiness of handling and difficulty of maintenance in operating light control system, were

discussed. Status feedback of the lamp is obtain by using remote street light controller module

(which is installed on lamp post), consisting of ZigBee module, digital circuit unit and power supply.

Cost effective Street Lights Monitoring Systems (CESMOS) 53



The lamp status is further communicated to Remote Concentrator (RC) which is installed zone

wise. This RC consist of Code division multiple access (CDMA) module, ZigBee module , display

screen, digital unit and power supply too. The RC, further communicate with central control center

for the analyzing the data and to decide appropriate action by using software.

Wu Yue ,Shi Changhong, Zhang Xianghong, Yang Wei [4], were discussed, the design of new

intelligent street light control system by using ZigBee communication protocol as referred above.

Sung Kwan Cho, Vijay Dhingra [5], had described, the street lighting control based on LonWorks

power line communication. It uses the interfacing electronic devices fitted on each and every lamp

post and communicates the status of a lamp to segment controller cum router. A very similar to the

monitoring systems discussed in [3].

David Daza, Ramon G. Carvajal, et al. [6], discussed the issues pertaining to street lighting

network formation mechanism based on IEEE 802.15.4 protocol. The main thrust was, to reduce

the number of gateways which are required to send the data to central management system.

On the similar lines, the respective authors of [7], [8], [9], had discussed the street light monitoring

system based on various communication protocols. In which, it was observed that, advanced

electronic modules are used for monitoring and controlling lamp ballast from central controlling

centre via segment or zonal controller with the use of various IT wireless network architecture.

The advancement and development in semiconductor technology, in very large scale

integration(VLSI), in Radio Frequencies (RF) communication with increase in allowable frequency

spectrum and in power line communication (PLC), created vast scope in present days street lights

monitoring systems. The development in digital electronics made rapid use of microprocessor,

microcontroller, microcomputer to make each device enough smart. Now days these high end

electronic components are the parts of street light monitoring systems. As explained earlier,

automatic switching and various advanced methods of control (monitor), using such high end

electronics were suggested and implemented by the scientist and engineers.

2. PRESENT SYSTEMS OF STREET LIGHT CONTROLS & MANAGEMENT SYSTEM

Along with the basic services (water, health, sanitation, roads and transport) to be provided by the

local city authorities, effective lighting along with roads and streets is a must priority for the citizen’s

safety. Presently, various methods are used to monitor and control street lights. Few popular

methods adopted to monitor street lights are listed below.

a) ON - OFF control by manual intervention

b) ON - OFF control by photo sensor (PS) and / or astronomical digital clock (ADCL)




c) Programmable logic contoller based ON – OFF/voltage control for group dimming facility

along with PS and ADCL

d) Individual lamp control with relay/electronic circuit, monitored from central location,

using different technologies for example- i] RF communication, ii] ZigbBee

communication protocol, iii] Power Line communication iv] LonWork communication

protocol, and v] IEEE 802.15.4 network protocol

From the listed methods, “a” and “b” are still functional throughout the world on large scale. As a

pilot project method “c”, is used in few cities for power saving after midnight hours till dawn. Due to

high capital investment, methods “a, b and c” are only use for the purpose of provision of adequate

illumination during night. No feedback of lamp status is send to controller for maintenance and

operational measures. Method “d” provides with variety of functions of monitoring, and energy

saving with communication directly from lamp post to central management system or from lamp

post to segment controller (monitor). This is further relayed to central management system. A

representation of common methodology adopted in the above technologies, for example using

ZigBee protocol, is illustrated schematically in the figure 1.

Figure 1: Street light monitoring using ZigBee protocol ( Courtsey www.wulian.cc)

In the figure 1, the overall electronic communication is divided, it two parts, namely short distance

communication and long distance communication. A short distance communication means a

sensed signal transmitted between individual lamp post and segment monitor (controller). A long




distance communication represents the communication between segment monitor and central

management system. To complete the functionality of long distance communication, existing

technologies, d(i) to d(v) uses, the present backbone of modern communication technologies,

such as- Global System for Mobile (GSM), General packet radio service (GPRS), CDMA etc., or

internet. For short distance communication, protocols such as Zigbee/PLC/ Lonwork (ANSI 709.2)

or KNX (KNX is a networking standardization based on EN 50090, ISO/IEC 14543) are used. All

these protocols, basically requires communication interface (a printed circuit board with lots of

semiconductor devices are mounted on it) with ballast, which adds to the cost of the project.

Presently, a massive development of mobile communication and its rampant and excess use

radiates hazardous electromagnetic field (electromagnetic smog) in the surrounding which is

creating health problems.

2.1. QUESTION OF E-WASTE AND ELECTROMAGNETIC RADIATION (EMR)

As per E-Street Project in Europe [10], on an average for each nine inhabitants, one light point is

required. In India for 4378 cities and towns [11], on an average 18 millions street light points are

required to provide safety during night. At present worldwide population is over 7 billion. It is

expected to grow as more than 9.26 billion. Out of the total figure, approximately, 70 percent of the

world population will be urban by 2050. The most of the growth will occur in less developed

countries. That is over 6.482 billion inhabitants will be living in urban area. Therefore to cater the

need of illumination on street, parks, roads etc., over 0.72 billion light points will be required. With

the use present technologies, it means same numbers of interfacing cards (PCBs) are going to

deployed on lamp posts just to know the status of street lights.

By considering total street light points worldwide, the staggering quantity (0.72 billion) of

electronics PCBs are required to communicate with segment controller to know the status of lamp.

If we can reduce this amount of e-waste, certainly it will be a great help to environment. The bad

effect of recycling of printed circuit boards on environment and human life is discussed [12], in the

reference. The question is, how we can reduce the number of interfacing PCBs, so that there will

be a reduction in the e-waste due to street lights alone. Answer to this question is affirmative. To

reduce this staggering quantity of e-waste, the innovation suggested in the project work, will have

to implement worldwide. Thus by reducing e-waste, it will help the utilities to focus on more

important issues.

Since, the inception of micro oven to cook the food in the advanced life style of citizens, the ill

effect of high frequency radiation is debated across the world. Today, the extensive use of cell

phones and other electronic communication devices are inevitable parts of our modern life. Various

government and non-government organizations are doing research on the issues of bad effects of

http://en.wikipedia.org/wiki/Standardization

http://en.wikipedia.org/wiki/EN_50090

http://en.wikipedia.org/w/index.php?title=ISO/IEC_14543&action=edit&redlink=1




electromagnetic radiation on life of humans and animals. The ionization effect of EMR damages

the Deoxyribonucleic acid (DNA) structure, as well as non-ionization effect of EMR is certainly

linked to specific diseases such as cancer. According to the FDA, a radiation-emitting device is

defined as, any product that uses electricity to power an electronic circuit. All electronic products

radiate electromagnetic at varied intensity levels. Even though, exposure to non-ionization

radiation from laptop is harmful too. In short, there is no real “safe” level of radiation exposure.

When it comes to be safe against EMR, is to avoid extra doses of electromagnetic radiation

whenever, where ever you can.

3. SCOPE OF DEVELOPMENT (INNOVATION)

In the world very few local civic authorities are strong in financial status. All others are always in

the socio economic crunch. With the issues of funds paucity, an installation of highly intelligent

solution for street lights is a distant dream. In India too, till date, not a single civic body is in a

position to deploy complete street lights monitoring system in the entire city. With the following

objectives, it is intended towards development of new cost effective technique for monitoring

streetlights.

A low cost solution, so that utilities from developing nations can get benefit of energy

saving and have less capital intensive, low operation and maintenance(O&M) cost

street lights monitoring system.

Utilities can help the nation to achieve the targeted emission of carbon di oxide (CO2 )

by sustainable reduction in energy wastage.

Huge reduction of e- waste and waste management costing.

A humble efforts to make mother earth green, clean, toxic free and EMR safe.

3.1. RESEARCH METHODOLOGY

Any Street light feeder (segment of street lights) is consisting of many number of lamp posts fitted

with luminaries. For the monitoring functionality, it is supported with additional electronic control

gear fitted on individual lamp post and in the cabinet of segment controller (monitor). The lamp

status, i.e., on or off is communicated to segment controller by using any one technology listed in

the section 2.0. This is further communicated to central monitoring system by using existing

information technology infrastructure. A proposed, CESMOS will be consisting of following

components-

I. Luminaries on the street lamp post.

II. The segment monitor in the power supply cabinet that handle and manage a

segment of street lights.

III. The mobile network that provides the communications between the segment




monitor and the back office or central monitoring system. For this communication,

existing GSM/CDMA information technology (IT) infrastructure can be used.

IV. The central monitoring system (management information system), allows the

management of all street lighting poles in a city/town.

The proposed system gives emphasis on the sensing parameters between segment monitor and

individual lamp. The status of individual streetlight can be obtained from segment monitor only.

Thus, we can completely eliminate electronics components required to interface with the lamp,

which is fitted in the luminaries. This interface is required by all other modern technologies to

declare the status of the street lamp. The CESMOS isn’t having any such interface between

segment monitor and individual lamp post. The research methodology was followed as -

i. Characterization of existing Street light configuration

ii. Algorithm to calculate required electrical parameters

iii. A proof of concept (POC). A working model is consisting of CESMOS with five lamp

post of street light feeder. To facilitate the work, it was decided that working model

(POC) would be supplied with dc power.

4. CHARACTERIZATION OF STREET LIGHT CONFIGURATION [13]

In any city or town main emphasis of deploying street lighting is to have adequate illumination level

on the roads. For this various designing software were used to decide number of lamp posts, type

of luminaries, and their arrangement along the street. For the implementation of proposed

CESMOS, street lighting is to be studied on the following points

i. Types of streets according to lights arrangement

ii. Characterization of single street light segment

4. 1. TYPES OF STREETS ACCORDING TO LIGHTS ARRANGEMENT In India, present lighting systems in urban cities are mainly deployed by municipal or local civic

authorities. A day to day operation, is governs by themselves or by local electric power distribution

companies. According to standards, to provide required illumination level on the street during night

period, various configurations of street lighting systems are used. These are broadly classified as-

i. Street with single luminaries on one side, which is illustrated in figure 2.

ii. Street with multiple Luminaries along the median (divider) of the road, figure 3.

iii. Street with single luminaries on the side and facing opposite, figure 4.

iv. Street with single luminaries on both side with staggered arrangement, figure 5.




Figure 2: Street with single Luminaire Figure 3: Street with multiple luminaries

Figure 4: Street with facing poles Figure 5: Street with staggered poles

These configurations [14], are supplied with three phase power of 415, volts 50 Hertz alternating

current (AC). Depending on wattage capacity of individual lamp ie 70 Watts(W), 150W and 250W,

and length of the circuit/street, within the constraint of permissible voltage drop, 6.0 sq mm,

10.0sq mm and 16.0sq mm, 4core , PVC/XLPE, 1100 V, Indian Standard, aluminum armoured

cables are mainly installed. Number of lamp posts on a single circuit is decided by the permissible

voltage drop, and the wattage capacity of a luminary, such that required level of illumination should

be obtained during night. A street distribution feeder ( or segment feeder) comprises of necessary

electrical switchgear along with timers and photo sensors. It may have additional hardware as

astronomical switch and transformer to dim the street lights after midnight hours.

The lamp post has suitable terminal box along with cutout or miniature circuit breaker. From

terminal box to luminaries, (2 + 1 runs) a single core PVC flexible wire or 3 core PVC flexible cable

of 2.5 sq mm, aluminum conductor, is laid.

4.2. CHARACTERIZATION OF SINGLE STREET LIGHT SEGMENT

Following are the main features of single street light segment deployed for a particular street, is

listed below.




i. According to standard IS 1944 (Part I,II,V,VI and VII) street light system for a particular

street will have fixed number of lamp post which are separated by a equal span.

ii. All Luminaires of same rating are used to satisfy requirement of lux level on that

street(Lamps type, rating and ballast or ignitor of same manufacturers)

iii. 6 sq. mm, 10 sq. mm and 16 sq. mm, 3- phase, 4- cored Al. conductor, PVC/ XLPE

insulated and armoured cables are used.

iv. Street lights are distributed amongst three phases, in R-Y-B-R-Y-B…..sequence

In India , cables of leading manufacturers such as Asian Cable, CCI, Finolex , Polycab etc.,

are used for street lighting installation. Confirming to Indian Standards IS 1554 / Part - I / 1988,

sample data for commonly used, aluminium, 4 core, PVC insulated, armoured cables of different

sizes is listed below.

Table 1: Parameters of 4 core , aluminium, steel armoured, PVC insulated Cable Size In Sq. mm

AC resistance at 70

0 C, 50 Hz

Ohm/Km

Reactance at 50 Hz Ohm/Km

Capacitance µF/Km

Impedance at 70°C Ohm/Km

Voltage Drop V/Km/A

10.0 3.7000 0.0938 0.60 3.700 6.410

16.0 2.3000 0.0862 0.80 2.300 3.980

25.0 1.4400 0.0854 0.84 1.440 2.500

Courtsey : Polycab Cables From the table 1, for the proof of concept, unit length parameters are selected for 10 sq.mm cable.

The street light configuration explained in the figure 2, is considered to explain monitoring

methodology of street lamps. For demonstration of POC, a segment of five street lamp posts with

same wattage capacity is considered. The schematic diagram of street segment with five lamp

posts connected to R-phase of the supply is explained in the figure 6. The effect of reactance and

capacitance is negligible compared to resistance of the cable. Hence, ac resistance is considered

as series impedance and lumped at the center of a span (a distance between two lamp post). At

each node or lamp post equivalent load impedance (total impedance of luminaries including all

electrical parts) is connected between phase and neutral. The electrical representation of a street

lighting is shown in the figure 6.

It is impended that, the impedance ( i.e. ratio of voltage to current) of the circuit is unique for each

case of individual non-working lamp post as well as for any combinations of non-working lamp

posts. This property is utilized for the building up of the algorithm and for development of

management software suitable for street light monitoring. If non-working lamp posts are more than

15 % of total street lights on a single phase, it is considered as a major fault and immediate

attendance of maintenance crew is required.

5. FUNCTIONAL BLOCKS OF CESMOS




1 Street Light power feeder Pillar 2 Terminal box of lamp post 3 Span of the lamp post

3

2 1

1

3

R Y

R

B R Y

R

B

Figure 6. : Electrical representation of street light

segment

To implement the concept of CESMOS, various devices are interfaced to achieve the desired

monitoring system. The functional blocks of CESMOS are represented in the figure 7. The

CSEMOS is mainly comprises of two main systems named as, segment monitor and central

management system respectively.

1

.

Figure 7 : Functional blocks of proposed CESMOS




The individual functions of each block and its location is listed in the table 2.

Table 2 : Description of blocks used in CESMOS

6. CONCLUSION

A successful demonstration of working model of CESMOS, as a proof of concept, is carried out.

Under the future scope, for actual deployment of the presented CESMOS, to monitor the street

lighting, it should be design as an industrial product. If presented CESMOS is implemented by

local civic authorities, in true sense, it will brings the following outcome- but not limited to-

A true Cost effective system for monitoring the streetlights.

Name of the Block Functions to be performed

Segment Monitor It is to be installed inside the street feeder panel and consisting of

integrated module such as current sensor, voltage sensor, ADC,

microcontroller and sending end modem.

Current sensor Consists of ACS 712 [15], hall effect current sensor, which senses the

current flowing through the street lights feeder.

Voltage sensor Consists of suitable PT for ac operation and resistance divider network

for dc operation. It senses the source voltage, which supply the power

to street segment

Analogue – Digital Convertor

(ADC)

Consists of 10 bits resolution inbuilt ADC functionality of

microcontroller board for precise current measurement. It receives

raw signal from current sensor and converts it into digital output

Microcontroller Ardunio UNO microcontroller board [16], is used to controls the

operations of ADC and GSM modem1.

GSM Modem 1 it transmits the SMS comprising of data related to particular street and

non-working street light over GSM network.

GSM network A dedicated GSM support from network operator to relay the signal

from segment monitor to central monitoring system

Central Monitoring System It is located at the electrical maintenance cell of local civic authorities.

It will have entire street lighting data such as street name , segment

monitor name, etc. It is broadly consists of recipient GSM modem and

monitoring server

GSM Modem 2 It receives data from GSM Modem 1 and passes to monitoring server

for further processing.

Monitoring Server After processing the data, it will pop up alerts about street lights status

and helps the administration to take various decisions related to

street lighting.




Ease on operation and maintenance of street lights

Use of data for administrative and managerial decisions

Huge saving of electrical energy over traditional method of street light maintenance

Reduction in CO2, to earn carbon credits

An alarm for power theft

Huge reduction of e- waste and waste management costing

No electromagnetic radiation pollution due to high frequencies

A major contribution to make environment more cleaner , more safer and lesser toxic

REFERENCES

[1] U.S. Food and Drug Administration(FDA),”Laws and Regulations (Radiation-Emitting Products)” [2] Paolo Vecchia, Rüdiger Matthes, Gunde Ziegelberger James Lin, Richard Saunders, Anthony Swerdlow,, Exposure to high frequency electromagnetic fields, biological effects and health consequences (100 kHz-300 GHz), A report by International Commission on Non-Ionizing Radiation Protection(ICNIRP), 2009 [3] J. D. Lee, K.Y. Nam, S.H. Jeong, S.B. Choi, H.S. Ryoo, D.K. Kim, “Development of Zigbee based street light control system,” IEEE PES Power Systems Conference and Exposition proceedings, October 29 – November 1, 2006,Sheraton Altanta Atlanta, Georgia, USA [4] WU Yue ,SHI Changhong, ZHANG Xianghong, YANG Wei,” Design of new intelligent street light control system”, 8th IEEE International Conference on Control and Automation ,Xiamen, China, June 9-11, 2010. [5] SungKwan Cho, Vijay Dhingra,” Street lighting control based on LonWorks power line communication”, Echelon Korea Asia Pacific Ltd., 27F WTC Samsung-dong, Kangnam-gu, Seoul,Echelon Corporation, 550 Meridian Avenue, San Jose, CA 95126 USA. [6] David Daza, Ramon G. Carvajal, et al., “Street Lighting Network formation mechanism based on IEEE 802.15.4”, Eighth IEEE International Conference on Mobile Ad-Hoc and Sensor-2011, University of Sevilla School of Engineering, Seville, Spain [7] Gustavo W. Denardin, Carlos H. Barriquello, Rafael A. Pinto, Marcelo F. Silva,Alexandre Campos and Ricardo N. do Prado,” An intelligent system for street lighting control and measurement” , Member, IEEE Federal University of Santa Maria – UFSM, Electronic Ballast Researching Group – GEDRE, 2009 IEEE ,Santa Maria, RS, 97105-900, Brazil. [8] Hengyu Wu, Minli Tang * (Corresponding author), Guo Huang, “Design of Multi-functional Street Light Control System Based on AT89S52 Single-chip Microcomputer”, 2nd International Conference on Industrial Mechatronics and Automation -2012, Qionghai, Hainan, 571400, China. [9] S. V. Viraktamath, G. V. Attimarad, “Power Saving Mechanism for Street Lights using Wireless Communication”, Proceedings of 2011 International Conference on Signal Processing, Communication, Computing and Networking Technologies (ICSCCN 2011), Attimarad Dayanand Sagar College of Engineering Bangalore, Kamataka, India. [10] Project Report on, “Intelligent Road and Street lighting in Europe”, E-street Project-2006-2008. [11] G. Hari Kumar, “Energy efficiency in municipal water pumping and street lighting: a potential candidate for CDM? ”, TERI , India. [12] Ing. Valer Micle and Drd. Ing. Valentin Tofană, “Environmental impact generated by the metal recovery processes from waste electric and electronic equipment industry”, 5th Research/Expert Conference with international participations ”Quality 2007”, Neum, B&H, June 06-09, 2007. [13] “Street lighting design and construction” , a Network Standard Ns119 , by Australian Grid, Sydeny, May 2011. [14] Thane Muncipal Corporation “ Street light tender document” 2014. [15] Hall effect current sensor,” ACS712,” The Allegro®, MicroSystem Inc. USA [16] http://www.arduino.cc/en/Main/ArduinoBoardUno




Li INTERCALATION PROCESS IN Si10H15/MONOVACANCY GRAPHENE MONOLAYER

COMPOSITE - IMPLICATIONS TOWARDS Li-ION BATTERIES

PRIYA FRANCIS1, S.V. GHAISAS1

1 Department of Electronic Science, Savitribai Phule Pune University, Pune-411007

Abstract

Silicon cluster and graphene together are expected to improve the energy as well as power density of Li-ion battery. The holding capacity of silicon for Li and its transport through the defective (vacancy clustered) graphene is expected to be responsible. Here we report the importance of vacancy for the Li intake process in hydrogen passivity Si10 nanoparticle (Si10H16 NP) using ab-initio methods. A single H vacancy in the Si10H16 NP allows the Li atoms to binde with it otherwise not. A maximum of three Li atoms were added into the single vacancy hydrogenated Si10 NP and further studied the interaction of these Lithiated clusters on monovacancy graphene monolayer. The minimum energy path of Li for transferring from single vacancy hydrogenated Si10 NP to graphene surface shows a very small barrier indicating easy mode of transfer of Li to graphene surface.

Key Words: Intercalation, Graphene,Li-ion Batteries.

1. INTRODUCTION

The search of new anode material in Li based batteries for the replacement of existing carbon

based material ends at Si because of its high Li intake capacity [1] apart from its abundance, low

cost, biomedical and semiconductor technology applications. However, to become a reliable

anode, silicon has to succeed in the following scientific and technical challenges. First one is the

mechanical fracture due to the large volume changes i.e. expansion and contraction during lithium

insertion and extraction during charging and discharging process. It is reported that the

electrochemical alloying reaction of Li with Si involves volume expansion of up to 400% during

lithium insertion [2, 3]. The large volume change induces stress in the material and leads to

cracking and pulverization of silicon, which causes the loss of electrical contact and thereafter

capacity fading. Again, the repetitive volume expansion and contraction constantly shifts the

interface between Si and the organic electrolyte, hence preventing the formation of a stable solid

electrolyte interface (SEI) layer, which in turn results in a low coulombic efficiency and a decrease

64 Priya Francis, S.V. Ghaisas



in capacity during battery cycling. The unstable SEI is another challenge that Si has to face as an

electrode [4]. Over the years the experimentalists and theorists have come up and been doing the

research to improve the performance of Si based anode materials. Most of the experimental work

is related to the morphology of the Si such as Si nano wires [2], nano tube [8], double walled nano

tubes [9], 3D porous Si particle [10],10 nm sized Si nano particles [11] and Si hollow nano spheres

[12]. The advantage of these nano structural aspect is i) the provision of empty space to

accommodate the Si volume changes ii) unconstrained strain relaxation without mechanical

fracture during Li insertion[13] . Usually these structures are been supported, encapsulated or

coated by carbon material for providing a good electrical contact [13 -15].Graphene is considered

as a potential electrode material for Lithium ion batteries [5]. To improve the performance of the

batteries, silicon clusters are embedded in graphene sheets [5]. It is observed that this combination

leads to relatively higher power and energy density in the batteries. While the presence of silicon

clusters help in holding larger number of lithium ions, the vacancy defects in graphene help in

transporting lithium ions. Experimental study on composite structures of silicon and carbon indicate

that Si/C composite structures have long cyclic life as well as high lithium storage capacity [6].

Experimental studies are also available in the reversible lithium storage in nano size silicon

graphene composites [7]. Motivated by experimental research works the present study aims at

understanding the lithiation process in Si10H16 NP and Li intercalation process in SinHm/Graphene

composite using first principles methods.The results of this study would be an addition to the

existing first principle study related to the Si/graphene/ composite for Li based rechargeable

batteries.

2.Computational Methods

We consider Si10H16 NP as the basic structure for the Li interaction process. It is conceived from a

bulk cut cluster of 10 Si atoms passivated by 16 H atoms [21, 22]. By removing an H atom from

this NP create a single vacancy, Si10H15 NP.Graphene monolayer is modeled by 9 x 9 supercell

consisting of 162 carbon atoms.A monovacancy is created by removing a single carbon atom from

the supercell. The Lithiation process in NP are calcualted using a 20 x 20 x 20 Å3 supercell .A

supercell in the lateral direction with a 20 Å vacuums in the vertical direction is used for the

calculation of Li / Si10H15 / graphite composite. The relatively large lateral supercell was used to

reduce the interaction of the vacancies with their periodic images so that they could be treated as

isolated defects. We used the calculated value of 2.451Å as graphene lattice constant. A spin

polarized density functional approach (DFT) is used with projector augmented wave (PAW)

pseudo-potentials [23,24]. Exchange correlation energy used for the calculation is from Perdew,

Burke, and Ernzerhof (PBE) [25]. The iterations are performed until the changes in energy and

forces between the consecutive runs are below 0.0001 eV and 0.001 eV/Å, respectively. Gamma

Li Intercalation Process in Si10H15/ Monovalency Graphene Monolayer Composite- Implications towards Li-ion Batteries

65



point calculations are performed for the geometry optimizations under Monkhost pack

scheme.Nudged Elastic Band (NEB) method is used for finding the minimum energy path for Li

transerfer from Si10H15 NP to the graphene surface.

3.Results and Discussions

Fig.1 shows the interaction of Li in Si10H16NP. Three different cases were considered here.1) A

single Li atom has been placed inside of Si10H16 NP. 2) A single Li atom has been place outside of

Si10H16 NP. 3) Two Li atoms have been placed one inside and outside of Si10H16NP. Fig. 1(a)-(c)

shows the corresonding optimized geomerties. From the formation energy values calculated by

using the following equation (1) it is clear that Li doesnot bind with the Si10H16 NP.

Ef = - {E total LixM - x Etotal Li- E total M} -----------------------------------------(1)

Where Ef is the NP formation energy, Etotal LixM is the total energy of hydrogenated silicon NP with

Li, Etotal Li is the total energy of an isolated Li atom, E total M is the total energy of hydrogenated

Silicon NP without Li, x represents the number of Li atoms added in the NP.

(a) (b) (c)

Fig.1. Interaction of Li with Si10H16 NP(a) Li inside of Si10H16, Ef =+0.37eV (b) Li outside of

Si10H16 NP, Ef = +0.18eV (c) Li inside and outside of Si10H16 NP, Ef =+0.31eV. Big sphere with

blue colour represent Si atom, small blue colourspheres represent H atom, and white

colour sphere represent Li atoms.(Colour scheme is same for all the figures)

The interaction of Li with a single H vacancy on Si10H16NP shows the improvement in the binding.

In all three cases Li atoms interacted with the Si10H15 NP.Fig. 2 shows the interaction of Li atoms in

Si10H15 NP.In the three different cases as mentioned above Li has bonded with Si10H15NP with a




Li-Si bond distance lies in the range of 2.3679 - 2.6777 Å. The interaction of Li atoms with this NP

changed the Si –Si bond distances from 2.3319 to a maximum of 2.4772 Å without breaking the Si

structure.

(a) (b) (c)

Fig.2. Interaction of Li with Si10H15 NP(a) Li inside of Si10H15, Ef = -1.90eV (b) Li outside of

Si10H15 NP, Ef = -2.76eV (c) Li inside and outside of Si10H15 NP, Ef =-2.82eV.

From the formation energy values it is clear that the presence of vacancy made possible Li

interactions in hydrogenated Silion NP. A vacancy creates dangling bonds and an excess charge

concentrates on that position and helps Li atom to bind with the NP.These characteristics of

hydrogenated Si NP are comparable with the characteristics of crystalline Si during the Li

interactions [15]. Experimental research work shows the improvement in the power density as well

as cycling performance of Li- ion batteries by using the combination of nanostructured silicon and

graphenen with vacancies or defects compared to the commercial graphitic electrode material [14].

After studying the Li interactions in Si10H16 and Si10H15 NP, we have studied the Si10H15NP

interaction on graphene to understand the Li interactions in SiNP/graphene composite. A

monovacancy graphene monolayer is been considered for the same. By removing a single carbon

atom from the graphene surface a monovacancy is created.Fig 3. shows the interaction of Si10H15

on monolayer graphene. The optimized geometry shows Si10H15 NP interacted with the graphene

surface by forming a H-C-Si bond. The Si10H15NP has given its single H which had been attached

to the Si atom having dangline bond.On the graphene surface this H atom is attached to the

carbon atom which is having the dangling bond.Here H-C ,S-C bond distances are respectively


67



1.09 and 1.98 Å .The binding energy for the combination is -2.13 eV.The presence of vacancy in

both the surfaces helps to bind strongly with a high binding energy.

Fig.3. Si10H15 on monovacancy graphene monolayer, yellow colour sphere represents

carbon atom.

The Li transfering process from inside the Si10H15 NP to the graphene surface has been performed

in to two steps. First to optimize the geometry of Li/Si10H15/monolayer graphene composite, where

the Li atom is placed (i) insdie of Si10H15 (ii) outside of Si10H15. In the next step Nudged elastic

band method (NEB) is used for finding minimum energy paths of the Li transitions from inside to

outside.The optimized geometries of Li / Si10H15 / monolayer graphene composite with binding

energy is given in Fig .4. Fig. 4(a) shows the optimized geometry of Li inside / Si10H15 / monovacancy

graphene composite. Through H-C-Si bond, Li / Si10H15 NP are attached to the graphene

monolayer. The Si-C and C-H bond distances are 2.0560 and 1.0784 Å respectively. Li is binded

inside of the Si10H15 NP and the Si -Li bond distance varies from 2.3852 to 2.6782 Å. The binding

energy of this composite structure is -1.24 eV. Fig. 4(b) shows the optimized geometry of Li outside/

Si10H15 / monovacancy graphene composite. Here Si atom bearing the dangling bond is shared

between C as well as Li atom with bond distances respectively 2.0991 and 2.6060 Å. Li atom is

attached to the graphene surface with a Li-C bond distance of 2.2728 Å. The H-C bond distance is

1.0614 Å. The binding energy of this configuration is -2.30 eV.

(a) (b)




Fig. 4. Optimized geometry of Li / Si10H15 / monovacancy graphene monolayer composite. where

Li is kept inside and outside of Si10H15 on monovacancy graphene. (a) Li inside (b) Li outside.

For using NEB methods, we have generated three images by changing the position of Li atom

manually.Performing the optimization of these three images along with the optimised geometry of

Fig. 4(a) and (b) as initial and final images, calcualted the minimum energy path for Li atom to

come out of the Si10H15NP. The corresponding images with minmum energy order is given in Fig.

5. From these images, the barrier potential is calculated and it is +0.128eV.These results shows

that Li atom transfer from inside the Si10H15 to the graphene surface is a very low barrier potential

process and Li atom can come very easly to the graphene surface.

Fig. 5. Intermediate three images for the minimum energy path (MEP) for the Li / Si10H15 /

monovacancy graphene monolayer composite (Li / Si10H15 / 9x9_1_G) system.

4. Conclusions

To summarize, the ab initio calculation of Li interaction process in Si10H16 NP reveals the

importance of the vacancy for the Li atom to interact with the NP. This result shows that as in the

case of crystalline Silicon [15], in hydrogenated Silicon NP also role of vacancy is important for

Lithiation process. The minimum energy path for the Li intercalation process in Si10H15/monolayer


69



graphene composite shows that Li atom can easily transfer from silicon NP to the graphene

surface with very low barrier potential.

Acknowledgement

We thank C-DAC India for the utilization of PARAM series of supercomputers for the calculations.

PF would like to thank Govt. of India for UGC-SRF/NET Fellowship.

REFERENCES

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Nanotechnol. 3, 31 (2008).

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[4] Hui Wu, Guangyuan Zheng, Nian Liu, Thomas J Carney, Yuan Yang, and Yi Cui,Nano Lett.

12, 904(2012).

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[8] Mi-Hee Park, Min Gyu Kim, Jaebum Joo,Kitae Kim,Jeyoung Kim,Soonho Ahn, Yi Cui and

Jaephil Cho, Nano Lett., 9,3844( 2009).

[9] .Hui Wu, Gerentt Chan, Jang Wook Choi, Ill Ryu, Yan Yao, Matthew T. McDowell, Seok Woo

Lee1, Ariel Jackson, Yuan Yang, Liangbing Hu and Yi Cui, Nature nanotechnology,7,

310(2012).

[10] Hyunjung Kim, Byunghee Han, Jaebum Choo, and Jaephil Cho, Angew. Chem. Int. Ed. 47,

10151(2008).

[11] Hyejung Kim, Minho Seo, Mi-Hee Park, and Jaephil Cho, Angew. Chem. Int. Ed. 49, 2146

(2010).

[12] Yan Yao, Matthew T McDowell, Ill Ryu,Hui Wu, Nian Liu, Liangbing Hu, William D Nix, and Yi

Cui Nano Lett. 11, 2949( 2011).

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Jaephil Cho,Nano Lett., 9(11), 3844(2009).

[14] Xin Zhao, Minjie Li, Kuo-Hsin Chang, Yu-Ming Lin,Nano Research,7(10),1429(2014).

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Liang, Hanbiao Cao, Fenjin Tang, Minsheng Lei, Bo Xu,Chuying Ouyang,Energy Technol. 1,

77(2013).

[16] Tu C, Ma X, Pantazis P, Kauzlarich SM, Louie AY, J.Am .Chem. Soc. 132,2016(2010).

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HONEY BEES HAVE GEOMETRICAL SENSE – A MATHEMATICAL APPROACH

SONAWANE D. S. 1, HIWAREKAR A. P. 2, DHANORKAR G. A.3

1 Vidya Pratishthan’s College of Engineering, Baramati, India, 2 Vidya Pratishthan’s College of Engineering, Baramati, India,

3 Vidya Pratishthan’s College of Engineering, Baramati, India

Abstract

Number theory plays a vital role in Mathematics. Some rare and interesting properties about the less liked number ‘six’ are discussed. Further using mathematical known theory, some real life examples are discussed which convince that other living beings too have mathematical sense. Key Words: Elementary Number theory, Partial differentiation, animal science, maxima, minima.

1. INTRODUCTION Honey bees collect honey which is useful in human life. It is seen that there is uniform shape of a

honeycomb. This fact enables to keep faith on the geometrical awareness of the honeybees. We

realise that for the same perimeter ‘p’ the area occupied by an equilateral polygon with ‘n’ vertices

goes on increasing as ‘n’ increases. In the process, the largest area is given by a circle.

Simultaneously, we must tile a plane surface without any portion missing. This is possible only for

the polygons from triangles to hexagon. Thus, a regular hexagon is the optimal polygon which

gives the largest area such that the neighbouring regular hexagons are well tiles together. Honey

bees are quiet aware of this fact and they are making use of this sound Mathematics in their

routine life.

While watching a cricket match, we eagerly wait for the most exciting stroke of the game - a

soaring six. There are some interesting properties of this less liked and little hated number.

2. MAIN RESULTS

There are various types of numbers such as perfect number, triangular number, prime number,

Armstrong number and many more. An attempt to investigate some interesting properties of the

number ‘six’ is made here.

72 Sonawane D.S., Hiwarekar A.P., Dhanorkar G.A.



2.1 Perfect number: If the addition of all divisors of a natural number excluding itself equals that

number, then it is a perfect number. E.g. 6, 28, 496, 8128,… . One interesting property of a perfect

number is that the sum of the reciprocals of all its divisors is always 2. Another property of a

perfect number is that it is a triangular number. The converse is not true.

2.2 Triangular number: Numbers like 1, 3, 6, 10, 15, 21, 28, … are triangular numbers. This is

because the number of crosses (x) equal to a triangular number can be arranged in the form of a

triangle.

If we group the set of even numbers as (2,4,6), (8,10,12), (14,16,18),… then we find that for every

group, the sum of first two numbers is a multiple of 6 while the third number is also multiple of 6.

2.3 Prime number: A natural number greater than 1 that can be divided only by 1 or itself.

Theorem 2.1: From the set of prime numbers 2, 3, 5, 7, 11, 13, 17, … ; for every number ‘p’

except 2 and 3, either p-1 or p+1 is multiple of 6.

Proof: A number is divisible by 6 if it is divisible by 2 and 3 both. For every number p, p-1 and p+1

both are even. i.e. divisible by 2. Further among the three consecutive integers p-1, p and p+1,

either p-1 or p+1 is divisible by 3. Hence, we conclude that for every prime number p except 2 and

3, either p-1 or p+1 is multiple of 6.

{6, 12, 18, 24, 30, 36, …} is a set of multiples of 6. The last digits are even numbers. Thus, if the

last digit of any number is odd, the number is not divisible by 6. Further when last digit is

i) either 2 or 8, the number obtained by deleting that digit forms the A.P. 1, 4, 7, …;

ii) 4, the number obtained by deleting that digit is from the A.P. 2, 5, 8, …

Now we discuss a very interesting problem which leads to a very important conclusion. For the

same, we have an important theorem as follows.

Theorem 2.2: For the same perimeter ‘p’, an equilateral triangle among all types of triangles gives

the largest area.

Proof: Consider that we have a thread of length ‘p’ units. We have to find the type of triangle

whether equilateral, isosceles or scalene which will produce maximum area. For this, we use the

theory of calculus. Let a, b and c be the sides of a triangle with perimeter ‘p’ such that the area is

maximum. By Heron's formula,

,s s aA ea s s cr b

where 2

a b cs . Here we put .p a b c

2 2 2 2

p p p pArea a b c .

Honey Bees Have Geometrical Sense- A Mathematical approach 73



12 2 2 2

16Area p p a p b p a b .

Let 4 3 2 2 24 4 4 4 12f p p a b p a b ab 2 28 8p a b ab (1)

where a, b are variables and p is a constant. For finding maxima and minima of the function f, we

differentiate it partially with respect to a and b respectively.

we get

3 2 24 8 12 16 8f

p p a b p ab ba

(2)

3 2 24 8 12 16 8f

p p b a p ab ab

(3)

0f

a gives

2 22 3 4 2 0p p a b ab b …

(4)

0f

b gives

2 22 3 4 2 0p p b a ab a … (5)

2 22 4 3 2 0a b p a p pb

2 24 3 4 3 8 2

4

b p b p p pba

2 2 24 3 16 9 24 8 16

4

b p b p pb p pba

2 24 3 16 8

4

b p b p pba

4 3 4

4

b p b pa

4 3 4

4

b p b pa and

4 3 4

4

b p b pa

2

pa and 2a p b

Case i) ,2

pa 2a a b c a b c … (6)

Similarly equation (4) gives b a c … (7)




(5) and (6) gives a b b a a b

(6) gives 0c 2

pa and 2a p b . Thus a b with 0c is no more a triangle but a line.

Case ii) 2a p b 2a a b c b b c

Similarly equation (4) gives a c . Thus, 3

pa b c .

22

28 16

fr p pb

a

2

,3 3

8

3p p

r p

2212 16 16

fs p pa pb

a b

2

,3 3

4

3p p

s p

22

28 16

ft p pa

b

2

,3 3

8

3p p

t p

2 4

,3 3

480

9p p

rt s p and ,

3 3

0p p

r .

So, f attains maxima at 3

pa b c .

Hence the theorem is proved.

Area of triagle

221

0.048116 3 3 3 12 3

p p p pp p .

Remarks:

2.1 We conclude that the area of every higher order polygon also will attain maxima when all the

sides are equal. The area of a regular polygon for a fixed value of perimeter ‘p’ will attain maximum

when it is a regular polygon.

Further for any polygon with ‘n’ vertices, the sum of internal angles is 2 180n and each angle of

a regular polygon is 2 180n

n.

2.2 Among all quadrilaterals, a square will give the maximum area. A square with perimeter ‘p’ will

have each side 4

p and hence the area will be

220.0625

16

pp .

2.3 A regular pentagon will have each internal angle 3 180

1085

and corresponding area will be

20.0688p . See Fig.1.




Fig. 1

2.4 A regular hexagon shown in Fig.2 will consist of six tiled equilateral triangles with each side 6

p

and each angle 3

c

. Hence, the area is 21

6 sin 60 0.07222 6 6

p pp .

Fig. 2

2.5 Thus, for the same perimeter ‘p’ the areas occupied by an equilateral triangle, square, regular

pentagon and regular hexagon are 20.0481p ,

20.0625p , 20.0688p and

20.0722 p respectively.

2.6 As the numbers of sides of a regular polygon ‘n’ tends to infinity, we get a circle. For a circle

with perimeter ‘p’, 2 r p . 2

pr

22 20.0796

2 2 4

p p pArea r p which is even larger than

that in the case of a regular hexagon.

2.7 But it is not possible to tile identical circles close to each other as shown below in Fig. 4 and

Fig.5. Some portion of the plane surface among the circles remains unutilized.




Fig. 3 Fig. 4

2.8 One more thing is that on a plane surface a number of regular hexagons with equal perimeter

can be tiled together with no any gap between any two regular hexagons which is not possible with

any higher order regular polygon. See Fig. 5 and Fig.6.

2.9 That might be the reason why honey bees love ‘six’. The cells in a bees’ honeycomb are

always hexagonal. Bees might know that the area of a regular hexagon is ultimately larger than

that of an equilateral triangle, square and regular pentagon without wasting any plane surface area

and will hold more honey for the same expenditure of material.

Fig. 5




Fig. 6

3.CONCLUSIONS

3.1 For the same perimeter ‘p’ the area occupied by an equilateral triangle, square, regular

pentagon and regular hexagon goes on increasing. In the process, the largest area is given by a

circle.

3.2 We can tile a plane surface without any portion missing by a regular polygon of order up to six

only.

3.3 Honey bees are small insects useful to human society as we get nutritious, herbal honey from

them. It is interesting to see that such a small species not only understands but also apply

mathematics in their routine life, why should not the humans?

3.4 Mathematics teaching can be made interesting if we invent examples wherein various living

beings apply mathematics and include such examples in our discussions with proper reasoning,

then the things will definitely be fruitful.

ACKNOWLEDGMENT

Authors are thankful to Dr. S. B. Deosarkar, Principal VPCoE, Baramati and Vidya Pratishthan,

Baramati for motivation and support to this work.

REFERENCES

[1] Ramana B. V. – Higher Engineering Mathematics, McGraw-Hill.

[2] Bali N. P., Goyal Manish – A Textbook of Engineering Mathematics, Laxmi Publications.

[3] Lagu R. G, Tarey D. T. – The Joy of Mathematics, OXFORD university press.

[4] http://en.wikipedia.org/wiki/Pentagon.

[5] http://en.wikipedia.org/wiki/Hexagon.

http://en.wikipedia.org/wiki/Pentagon




IMPACT OF QUALITY MANAGEMENT ON MACROECONOMIC VARIABLES

SAIKAT GHOSH1, DR. AMARESH KUMAR2

1. PG (M.Tech) Scholar, Manufacturing Engineering Department, National Institute of Technology, Jamshedpur 2. Associate Professor, Manufacturing Engineering Department,

National Institute of Technology, Jamshedpur

Abstract

The main purpose of this study is to build an effective model which indicates the impact of Quality Management on various Macro-economic variables such as inflation, exchange rate and foreign direct investment. The main assumption taken to establish the relationship is that there is single monetary policy irrespective of the country. A conceptual model has been proposed in this paper and to show the relation, various statistical tools such as scatter diagram, correlation test, Regression analysis, Durbin Watson statics & analysis of variance (ANOVA) are computed by Minitab17. For the purpose of developing this model Gross domestic product (GDP) growth acts as a bridge between Total Quality Management and foreign direct investment (FDI), inflation, exchange rate. Where the first relationship is shown between the Sigma level (Quality management index) and GDP, in the later parts the relation between GDP and Consumer price index (inflation index), FDI and Exchange rate are shown. The mathematical relationships between the variables are also established here. From this analysis we strongly conclude that there is positive relation between Quality Management and GDP, inflation, FDI, exchange rate.

Key Words: Sigma level, GDP, Exchange rate, FDI. 1. INTRODUCTION

This study attempts to correlate Quality Management and Macroeconomic variables.

1.1Quality Management

In any competitive economy, continuous quality improvement is one of the most essential

aspects. Competitiveness is measured by three parameters- quality, price and delivery

[1].Quality has become the most important consumer decision factors in the selection among

competing products and services. The phenomenon is widespread, regardless of financial

institution, or a military defense program [2]. Understanding the market and continuous

Impact of Quality Management on Macroeconomic Variables 79



improvement in quality leads the organization towards success and growth. However, the main

goal of implementing quality initiatives has been to increase the satisfaction level of customer

[3].

1.1.1 Sigma level

Sigma level estimates the defects rate per million level opportunities. Generally sigma level

determines how well a process is maintained. The higher the sigma level not only is the

indication of less defect rate but also shows a better quality management.

1.2 MACROECONOMIC VARIABLE

Economics focuses on the behavior and interactions of economic agents and how economies

work. Macroeconomics analyzes the entire economy (meaning aggregated production,

consumption, savings and investments), and the issues affecting it including unemployment of

resources and the public policies that address the issues like monetary, fiscal and other policies.

Macroeconomics is a study of economy with broader vision. It examines the economic wide

phenomenon such as inflation, economic growth, exchange rate, unemployment rate and many

more. Macroeconomics evaluates the economic growth and performance either in comparison

of other economies or time series analysis. The goal for studying macroeconomics is not to

explain economic growth but also improve the economic policy. Here the term monetary policy

means the management of a specific nation‟s money.

1.2.1 Gross domestic product (GDP)

Gross domestic product equals the total value of goods and services produced in a country

during one fiscal year. Economic growth can be measured by the amount of goods or services

produced in an economy over a specific time period where as economic growth is sated as “a

multidimensional process of change focused on the betterment of the community state, and/ or

country and aimed at producing more „life sustaining‟ necessities such as food, shelter, and

health care and broadening their distribution, raising standards of living and individual self

esteem, and expanding economic and social choice” (Todaro 2005, page 4). Economic growth

and economic developments are often use as an interchangeable term.

Developmental theories would like to add healthcare availability, education attainment, political

freedom and equality of income distribution also with GDP per capita to measure the

80 Saikat Ghosh, Dr. Amaresh Kumar



development. Modern theory like to add some more attributes like infrastructure, lack of trade

barriers and fair judicial systems.

1.2.2 Inflation

One of the most important concepts of macroeconomics is inflation. When the price level rises,

each unit of currency buys less goods or services than previous [4]. Inflation affects an economy

in both the positive and negative way. Negative inflation increase in the opportunity cost of

holding money, whereas positive inflation may discourage investment and savings, and if

inflation were rapid enough, shortages of goods as consumers begin hoarding out of concern

that prices will increase in the future. Here for the purpose of examine this study; Consumer

Price Index (CPI) is used. CPI measures changes in the price level of consumer goods and

services purchased by households. The annual percentage change in a CPI is used as a

measure of inflation. Generally developed countries like US, UK, Japan uses CPI as an inflation

index.

1.2.3 Exchange rate

It is the relation between two currencies, rate at which one currency will be exchanged with

another one. It generally indicates the purchasing power of one currency for same item or goods

with the respect of another currency. Abruptly exchange rate shows the competitive value

among those specific countries monetary policy.

1.2.4 Foreign direct investment (FDI)

FDI is a controlling ownership in a business enterprise in one country by an entity based in

another country [5]. FDI is the investment from overseas for merger and acquisition, new

infrastructure growing and reinvestment.

2. MAIN RESULTS

The stated model tries to prove a strong relationship among variables. Data, those are taken to

show the relationships are: GDP vs. Sigma level: Regional economic data from China Statistic

Yearbook, 2010 [6] & GDP vs. CPI, FDI, Exchange rate (time series data from 1980-2010,

India): The World Bank IBRD IDA. The relation 1 is in the context of China and others are in the

context of India, as told previously it is assumed that there is single monetary policy irrespective

http://en.wikipedia.org/wiki/Currency

http://en.wikipedia.org/wiki/Opportunity_cost

http://en.wikipedia.org/wiki/Investment

http://en.wikipedia.org/wiki/Good_%28economics%29

http://en.wikipedia.org/wiki/Hoarding




of countries. Here for showing the relationship sigma level, CPI are used as the index of Quality

management and inflation respectively.

2.1 SCATTER DIAGRAM

Scatter diagram is a tool that analyzes the relationship between two variables for a set of data.

The data is displayed as a collection of points, each having the value of one variable

determining the position on the horizontal axis and the value of the other variable determining

the position on the vertical axis [7].

Figure 1

87654321

3.6

3.4

3.2

3.0

2.8

2.6

Sigma level

GD

P g

row

th

Scatterplot of GDP growth vs Sigma level




Figure 2

Figure 3

100806040200

10

8

6

4

2

0

Consumer Price Index

GD

P G

row

th

Scatterplot of GDP Growth vs Consumer Price Index

5040302010

10

8

6

4

2

0

Exchange Rate

GD

P G

row

th

Scatterplot of GDP Growth vs Exchange Rate




Figure 4

It is found that there is positive gradient and linear correlation for the entire fig Nos. 1 to 4. For

this case, to find the correlation factor correlation analysis is done in the next.

2.2 CORRELATION ANALYSIS

Correlation is important because it can easily indicate a predictive connection of data sets. It

tells us two things: direction of the relationship and degree of the relationship. In this paper

Pearson‟s Product Moment correlation coefficient (PPMC) & Spearman‟s rank order correlation

coefficient (Spearman rho) are calculated with the use of Minitab17. Theoretically the range for

these coefficients should be between -1 and +1.

Relationship

No.

Relation between

(Variables)

Pearson‟s Product

Moment correlation

coefficient

Spearman‟s rank

order correlation

coefficient

1 Quality

management

(Sigma level)

GDP

growth

.970 .991

2. GDP growth Inflation .456 .405

0.40.30.20.10.0

10

8

6

4

2

0

FDI

GD

P G

row

th

Scatterplot of GDP Growth vs FDI




(CPI)

3. GDP growth

Exchange

rate

.325 .290

4.

GDP growth FDI .292 .395

Table 1, Correlation coefficient

Here both the correlation coefficient PPMC and Spearman rho are calculated. For examine the

correlation analysis the higher value of coefficient will be analyzed. For the first relationship

between sigma level and GDP growth Spearman correlation coefficient is calculated as .991,

which shows a very strong correlation between them. For the explanation of GDP growth CPI

relation, PPMC has more numerical value (.456) than Spearman rho. Interpreting this we can

found a moderate correlation among them. PPMC holds greater value (.325) for the Exchange

rate and GDP growth relation also, hence it proves a weak correlation and for the last case,

GDP growth and FDI spearman rho (.395) conclude a correlation of marginal level between

moderate and weak.

2.3 REGRESSION ANALYSIS

Regression analysis is a statistical process, used for estimating the relationship among various

variables. It specially analyzes how dependent variable changes when independent variable is

changed. For this specific purpose linear, quadratic and cubic regression are analyzed.

Relationship

No.

Relation between

(Variables)

Coefficient of

determination

(

Standard

error of

regression

(S)

F value P value

1 Quality

management

(Sigma level)

GDP

growth

96.6% .0833 28.72 .010




2 GDP growth Inflation

(CPI)

23.3% 2.11 4.21 .025

3 GDP growth

Exchange

rate

16.1% 2.20 1.73 .185

4 GDP growth

FDI 36.4% 1.92 5.14

.006

Table 2, Regression & ANOVA

According to the numerical value of (largest one) the respective regression type is selected

for the interpretation. Here Cubic regression line is found suitable one for GDP vs. sigma level,

GDP vs. exchange rate, GDP vs. FDI study, and Quadratic regression for GDP and CPI

relation.

2.3.1Interpretation of coefficient of determination (

Coefficient of determination measures how well the regression line represents the data. It is

useful because it gives the proportion of the variance that is predictable from the other variable.

is always in the range from 0 to 1. It represents the percent of data that is closest to the line

of best fit. For the first case it is proved that about 96% of the total variation in GDP growth

attributed to sigma level. On the later part there are almost 23%, 16%, 36% dependency of CPI,

exchange rate and FDI upon GDP growth respectively.

2.3.2 Interpretation of standard error of regression (S)

Standard error of regression represents the average distance between the observed values and

the regression line. Smaller value of standard error is expected because it indicates the

observations are closer to the fitted line. Here for this purpose we have found .08%, 2.11%,

2.20%, 1.92% average distance of the data point from the fitted line, for all the 1 to 4 relations.

S must be <= to produce a sufficient narrow 95% prediction interval [http://blog.minitab.com].

Hence all the values here are in the level that shows a better result.

http://blog.minitab.com/




2.3.3 Interpretation of P & F value

The P value or calculated probability is the estimated probability of rejecting the null hypothesis

( ). The term significance level ( ) is used here to refer to a pre chosen probability. Hence we

can assume that

Null Hypothesis ( : There are no relationship between the relation no.1,2,3,4

Alternative hypothesis ): there are relationships among the relation no. 1,2,3,4

(Opposite to null hypothesis)

Theoretically when P < α, it is assumed that null hypothesis is rejected. Later Fisher

suggested a probability of one in twenty (0.05) as a convenient cut off reject the null

hypothesis [8] .That‟s why the 3rd relation shows null hypothesis is true and for the other

cases null hypothesis are false.

Here for the respective relations, F values are 28.72, 4.21, 1.73 and 5.14. It is very much

clear that when F to have a value close to 1 it shows the null hypothesis true [9]. So for

this specific purpose the 3rd relation shows the null hypothesis true, else all the relation

depicts that there alternative hypothesis as true.

2.3.4. Mathematical relation

With the help of regression analysis it is found that there is mathematical relationship (according

to type of regression, standard error of regression, value) between all the relations stated

here.

GDP growth= 2.167+.487 - 0.07562 +.004707 ………………………………..

i

GDP growth= 5.977- .0573 + .001540 ……………………………………………

ii

GDP growth= 11.18 -.8288 + .03217 - .000349 …………………………….

iii

GDP growth = 5.378 + 21.72 + 54.9 -259.4 ………………………………

iv

.4867 - .07562 + .004707 3.319 - .01365 + .000566 ……………

v

.4867 - .07562 + .004707 = 9.013 - .8288 + .03217 - .000349 vi




4867 - .07562 + .004707 = 3.211+ 21.72 + 54.9 -259.4 … vii

2.4 Durbin Watson Test

For examine this rule we can assume that there is no relation for the relation no. 1,2,3,4.

Relationship

No.

Relation between

(Variables)

Autocorrelation

coefficient

(Durbin Watson

statistic)

1 Quality

management

(Sigma level)

GDP

growth

2.01011

2 GDP growth Inflation

(CPI)

2.01991

3 GDP growth

Exchange

rate

1.82998

4 GDP growth

FDI 1.92349

Table 3, Durbin Watson statistic

The values of Durbin Watson test always between 0 and 4. But it totally depends upon the

degree of freedom on both the variable. And after tally both the upper limit and lower limit for all

the cases it is found that there is according to the Durbin Watson table the all the calculated

points lies in the part where probably false. Which proves that there is relation between

sigma level, GDP, CPI, exchange rate. For all the cases DW > , this means that the

regression results are sensible and the model can be accepted.




3. CONCLUSIONS

Throughout the experiment positive gradient are found for all the scatter diagrams. Linear

correlation has been found among all the variables, in the range from very strong to weak. Later

the coefficient of determination shows a maximum dependency around 96% whereas the lower

as 16%. In the 95% significance level standard error of regression shows its results between

predefined limit. Whereas through the P & F value interpretation the 3rd relation is found to be

null hypothesis true, rest shows the payoff as stated model. Here autocorrelation coefficient

found as significant. Mathematical relationship from regression analysis and DW > make the

proposed model significant.

Quality Management

(Sigma level)GDP Growth Exchange Rate

Inflation

(CPI)

FDI

1 3

4

2

Figure 5, proposed model




REFERENCES

[1] ATotal Quality Management , B. Janaikrisnan, R.K. Gopal , PHI learning pvt ltd, ISBN No.-978-81-2295-9

[2] A Introduction to Statistical Quality and Control, Douglas. C. Montegomary, John Willey

& sons, ISBN No.-978-0-47-16992-6

[3] An empirical investigation of the relationship between quality initiative and financial performance, Ali Uyar, Eurasian Journal of Business and Economics, 2008

[4] Why price stability?, Central Bank of Iceland, Accessed on September 11, 2008.

[5] Zhang et al., International conference of Artificial Intelligence and software Engineering, 2013

[6] Utts, Jessica M. Seeing Through Statistics 3rd Edition,Thomson Brooks/Cole, 2005, pp

166-167. ISBN No. 0-534-39402-7

[7] Quinn, Geoffrey R; Keough (2002) Experimental Design and Data Analysis for Biologist (1st edition) Cambridge, UK Cambridge University pp 46-69, ISBN No. 0-521-00976-6

[8] J.H. Zar, Bio-statistical analysis, fifth edition 2010, ISBN No. 0131008463

http://www.sedlabanki.is/?PageID=195




DESIGN AND DEVELOPMENT OF COMPUTER CONTROLLED ELECTRO-MECHANICAL MOUNT FOR

MANEUVERING AN ASTRONOMICAL TELESCOPE

SANKET GARADE1, PROF. DR. RAJIV B.2 1Department of Production Engineering and Industrial Management,

College of Engineering, Pune 2Associate Professor, Department of Production Engineering and Industrial

Management, College of Engineering, Pune

Abstract

It is essential requirement in area of astronomical research to develop a machine (known as alt-az mount) with which it will be helpful to track and view astronomical objects. This mount will be helpful in maneuvering a telescope and controlling it to point to the desired object in the sky. Computer software will send slew commands (for movement) to the mount which will in turn maneuver the telescope using electronic motors and mechanical assembly of the mount. The mount can be operated in 2 modes – Normal and Scanning. In Normal mode, the mount will simply move the telescope according to the arrow keys (up/down/left/right) selected on the software. In Scanning mode, the telescope will perform a line by line scan of the area of the sky selected in the software.

Key Words: Telescope, mount, alt-az, stepper motor, worm gears.

1. INTRODUCTION

A. Telescope

A telescope is an instrument that gathers light and focuses that light into an image. In turn, this image

can be magnified for viewing. A telescope is mounted in such a way that allows you to swing it freely

from one object to another in the sky.

An astronomical telescope is used to observe celestial objects such as planets, stars, deep-sky-objects

such as galaxies, nebulae, comets etc.

B. Telescope Mounts

Telescope mounts come in various types. The most two common types are equatorial mounts and alt-

az (altitude-azimuth) mounts.

Equatorial mounts are more complex to design but are ideal for astronomical viewing as it allows

movement aligned to the celestial objects i.e. about the polar axis.

Design and Development of Computer Controlled Electro-mechanical Mount for Manoeuvring an Astronomical Telescope

91



Alt-az mounts are comparatively simpler to design and are primarily meant for terrestrial viewing.

However these mounts are also used for astronomical viewing. The mount discussed in this paper is an

alt-az mount.

C. Need of an automated mount

An automatic mount facilitates fast navigation of the night sky when doing night sky observations.

Compared to manual navigation of the telescope, an automatic mount requires less physical efforts

as well, which can be very higher especially when using heavier telescope (larger than 8 inch scopes)

In cold regions, staying out in the cold for an entire night doing observations can be a problem. In

such cases, the observation can be done by sitting inside a room and controlling the scope using a

computer.

For long exposure photographic observations, a mount is used to avoid star trails which occur due

to the rotation of the earth.

Sky survey is done by many amateur astronomers around the world. In this, they scan an area of

the sky looking for possibly new comets/meteors etc. This scanning can be done with minimum efforts

when using a automated mount.

2. REQUIREMENT SPECIFICATIONS

Load specifications: The mount must be able to maneuver a telescope which is maximum 1kg in

weight and has maximum dimensions: length = 18 inches and diameter = 3 inches

Performance specifications: The mount should have an angular resolution of 0.1°.

Power specifications: The mount must be powered by 12v dc voltage either through a power supply

or a battery.

Dimensions: the mount (excluding the telescope) must fit in a box of 30cm x 30cm x 60cm.

Communication specifications: It should communicate with an external device like PC/laptop over

serial port. This communication will be used to carry the motion commands and information from PC to

the mount and vice versa.

3. Methodology

The entire system will be as shown in the block diagram (Figure 1). The computer will be the master of

the system and will issue commands to the electronic control board. This board will accordingly drive

the stepper motors using the motor driver boards. The stepper motors will be connected to the gear

92 Sanket Garade, Dr. Rajiv B.



boxes which will finally cause the motion of the 2 axes of the mount. The 2 axes will be vertical and

horizontal,

Figure 1- Block Diagram

known as altitude and azimuth axes respectively in astronomical terms. Hence the mount is also called

an “alt-az” mount.

Each gear box contains 1 worm and worm-wheel gear set. The worm is driven by a stepper motor

having step angle 0.9°. The worm-wheel is connected to the load. In case of azimuth motion, the load is

the horizontal turn-table (red colour in Figure 3) along with the attached telescope. In case of altitude

motion, the load is the telescope.

4. OPERATING MODES

The mount will be operated in 2 modes – Normal and Scanning. Overview of the same in shown in

Figure 2.

A. Normal mode

In this mode, the telescope will be simply moved up/down/left/right using the arrows keys on the

software. The resolution of the movement can also be controlled from the software. Lesser resolution

will be used in moving the telescope from one point to another when the points are far away. This will

help is faster movement. On the other hand, higher resolution will be used to perform very small

changes in the telescope’s position. This will result in slower but fine control when pin-pointing to

objects in the field of view of the telescope.


93



B. Scanning mode

In this mode, the telescope will be used to scan a particular region of the sky. This kind of scanning

activity, performed by amateur astronomers, is called “sky survey”. Sky surveys result in observing and

finding new celestial objects such as comets.

In this mode, the arrow keys will be used to position the scope to a desired start point in the sky. Then,

the area to be scanned (e.g. 5° x 3°) will be entered along with the desired quadrant.

On pressing the “Zero” button, the mount will begin line-by-line scan of the selected quadrant and will

cover the selected area of scan. The scan will be performed in a pattern where the scope will traverse

the horizontal dimension first (i.e. 5°) and move up/down in a small vertical increment of 0.5° (fixed). It

will again cover the horizontal distance followed by another vertical increment and keep on doing this till

the vertical dimension (3°) is fully covered.

Figure 2 - Operating modes

The speed of scanning can also be selected from the software before beginning the scan.

5. DESIGN

The design of the mount system is split into 3 parts each of which is given below.

A. Mechanical design

The mount is divided 2 sections according to the drive direction – Horizontal drive (blue) and vertical

drive (red). The horizontal drive is enclosed in the base of the mount. It drives the turn-table on which

the vertical dive assembly rests.




The vertical drive assembly consists of 2 pillars. One pillar houses the vertical drive whereas the other

acts as a support to the telescope. Both these pillars have coinciding shafts which protrude out to

connect to the telescope.

The 3D model of the mount is developed using CATIA V5 software.

Figure 3 - Designed model of the alt-az mount with the telescope

Both the drives have similar construction. Each drive consists of – stepper motor, coupling, worm-wheel

gears and bearings. The stepper motor shaft is connected to the worm shaft through an encoder

coupling. The worm gear is made from EN-8 mild steel and the worm-wheel is made from Phosphor-

Bronze material. The gears are assembled in a housing made of 6mm thick acrylic sheets. 10mm inner

diameter ball bearings are used to support the gear shafts.

B. Electronic design

The electronics module consists of a control board and 2 motor driver boards.

The control board takes commands from the PC over the serial port and in turn gives drive signals to

the driver boards. It also sends back to the PC status of the controller and other information. The

control board uses an ATMega32 micro-controller.

Two driver boards are used, one for each drive. The driver board uses a L297 IC as the stepper motor

controller. It receives the driving clock pulses and other control signals from the control board.

Depending on this, it issues the winding sequences according to the selected step mode and direction.

The winding sequence is given to the driver IC L298N which has a H-bridge driver within. The motor’s

four windings are connected to the four outputs of the L298N in a bipolar motor configuration.


95



A stepper motor with 0.9° step angle is used as a prime mover. It is used in full step mode to maximize

the torque output. The motor is of a standard NEMA 17 size.

The control board also has a failsafe feature wherein it stops the mount operation in case of a

communication failure, i.e. if there is no communication received from the PC for a timeout period of 2

seconds.

Figure 4 - Electronic design - block diagram

The schematic and board layout is designed using ExpressSCH and ExpressPCB software

respectively.

The entire electronics is powered from a 12V DC power supply adapter.

C. Software design

The screenshot of the developed software is shown in Figure 5. This software application is used to

control the telescope in both the operating modes.

To start, the COM port of the PC is selected from the drop down menu. The “Connect” button is used to

connect to the selected COM port and then “Start” button is pressed. Default selected mode is

“Normal”. The arrow keys in the “Normal” frame can be used to the move the telescope in the

respective directions.




Figure 5 - Mount control software interface

By selecting “Scanner” button, the mount enters the scanning mode. Here it needs to be brought to an

initial position using the four arrow keys. Once the initial position is set, the Quadrant and Area is set

and scanning can be started by pressing the “Zero” button. Once scanning has started, the arrow keys

cannot be used till the scanning is complete. If it is needed to stop scanning at anytime, the “Stop”

button can be used to do the same.

The status strip at the bottom of the window gives various statuses received from the mount’s electronic

control board.

The software application has been developed in Microsoft Visual Studio using C# language.

6. CONCLUSION

An alt-az telescopic mount was successfully designed and developed from scratch. The developed

mount was able to achieve the targeted system requirements such as 1Kg load and 0.1° angular

resolution. It is working correctly as per the designed operating modes and their controls. The failsafe

feature is also working as expected and stops the mount in case of communication failure.

References

[1] Permanent Magnet Motor Technology – Jacek F. Gieras

[2] http://www.celestron.com/support/knowledgebase

[3] http://ascom-standards.org/

[4] http://www.skyatnightmagazine.com/

http://www.celestron.com/support/knowledgebase

Proceedings of 6th National Conference on Multidisciplinary Research in Science & Engineering, MIT AOE

Alandi, Pune, 5-6 June 2015, pp.97-104, ISBN: 978-93-84648-83-1



GaN SCINTILLATOR DETECTOR CHARACTERIZATION SIMULATION GEANT4 SOFTWARE AND VOLTAGE PRE-

AMPLIFIER SIMULATION

SELVA HEPSHIBHA1, DR. P.P. VAIDYA2

1Lecturer, Dept. of Instrumentation, V. P. M. Polytechnic, Thane, India 2HOD, Dept. of Instrumentation, V.E.S. Institute of Technology, Mumbai, India

Abstract

This paper describes GaN as a Scintillator Detector, its properties and its characterization using Geant4 software.

Scintillator Detectors are widely used to detect radiation with very high accuracy, and novel

scintillators are the need of the hour. Actual hardware testing of nuclear radiation detectors is difficult and subject to various legal contingencies, hence software simulation setup of the entire system is the most optimum solution, and this has led to the following research. Also the electronic output of such a scintillator is further processed using a Voltage Pre-amplifier circuit; such that optimum, noise reduced output can be obtained.

Key Words: Scintillator detector; GaN detector; Geant4 software;detector characterization, Voltage Pre-amplifier. 1. INTRODUCTION

The need of nuclear detection covers multitude of areas ranging from agriculture to medicine, from

weapons to power.

There are various types of nuclear radiation detectors like Gas filled detectors (IC), Scintillator

Detectors and Semiconductor detectors.

Scintillator detectors have multiple features that motivate me towards this area of research. Few

of them are listed below:

High density

High efficiency for converting the energy of incident radiation into scintillation photons

Transparency to its own scintillation light (for good light collection)

Good linearity over a wide range of energy

98 Selva Hepshibha, Dr. P.P.Vaidya



A short rise time for fast timing applications (coincidence measurements)

Low cost

Radiation hardness

Production capability and

Durability of operational parameters.

There are numerous types of Inorganic Scintillating crystals available in nature in abundance.

This paper puts light on GaN as a novel scintillating detector due to its following properties:

Available in both Wurtzite and ZincBlende crystal structure.

Wurtzite type exhibits Scintillating properties.

Density 6.15gm/cm3

Direct band gap

Excitonic emission around 3.4eV

2. SCINTILLATION PRINCIPLE

If a material gives off light when radiation interacts with it, it is said to scintillate. The amount of light

given off is proportional to the amount of incident radiation. This light can be measured and the

information used to calculate the amount of radiation exposure.

Different types of scintillating material are used to detect different types of radiation. For eg, a thin

layer of Zinc Sulfide is generally used to detect alpha radiation; an Anthracene crystal is used for

beta; and a NaI(Tl) activated crystal detects gamma. The basic functioning of the detector is the

same no matter what type of scintillation material is used.

a. Working of a Scintillator

Crystal structure of inorganic materials determine their energy states and thereby the Scintillation

properties of the same. Electrons have discrete band of energies in crystal lattice: Valence (lower)

& Conduction (Upper). Electrons absorb energy and get elevated to higher levels; however in the

pure crystal form the return of electron to Valence band is inefficient. Further, the typical gap widths

are such that the resulting photon’s energy is too high to lie in the visible range.

GaN Scintillator Detector Characterization Simulation Geant 4 Software and Voltage Pre-

amplifier

99



Impurities called as activators are added to create special sites in the lattice, at which the normal

energy band structure is modified from that of the pure crystal. This creates energy states in the

forbidden gap, through which the electrons can de-excite back to the Valence band, and emit light

in the visible range. These sites in the crystal lattice are called Luminescence centres or

Recombination centres.

The extremely low light output of a scintillation pulse, brings to light the need of a device to convert

light signals into usable current pulse, without adding noise to the signal. PMT serves this purpose.

They find applications in optical spectroscopy, laser measurement and astronomy.

B. Study of an existing Scintillator Detector

Figure 1. Image of an Existing Scintillator Detector

Figure 2. Block diagram of the above Scintillator Detector

Scintillati

on Head

Shaping

Amplifier SCA Counter/

Timer

High

Voltage

Supply

Low

Voltage

Unit




The various components of the NaI(Tl) Scintillator is listed and explained briefly below:

1. Scintillation Head (SH 644/ SH 644W)

a. NaI (Tl) Scintillator

b. Photomultiplier tube

c. Preamplifier

2. High Voltage Unit (HV4831B)

3. Counter timer (EC5104)

4. Single Channel Analyzer (SC604C)

5. Shaping Amplifier (PA 4901)

6. Compact 8K Multi Channel Analyzer system

3. GEANT4 SOFTWARE

Geant4 stands for GEometry ANd Tracking. Geant4 is a toolkit for the simulation of the passage of

particles through matter. It uses Monte Carlo methods. It is the successor of the GEANT series of

software toolkits developed by CERN.

Its area of application includes high energy, nuclear and accelerator physics, as well as studies in

medical and space science. The software is open sourced and is used by a number of research

projects around the world. Geant4 is provided under the Geant4 Software License.

A. Features Of Geant4

Geant4 provides the following features which allow less time needs to be spent on the low level

details, and researchers can start immediately on the more important aspects of the simulation.

(i). Geometry: It is an analysis of the physical layout of the experiment, including detectors,

absorbers, etc. and considering how this layout will affect the path of particles in the experiment.

(ii). Tracking: It is simulating the passage of a particle through matter. This involves considering

possible interactions and decay processes.

(iii). Detector response: It is recording when a particle passes through the volume of a detector,

and approximating how a real detector would respond.

(iv). Run Management: It is recording the details of each run (a set of events), as well as setting up

the experiment in different configurations between runs.

(v). Visualization, Histogramming, Multi-threading, etc.


amplifier

101



4. SCINTILLATION PRINCIPLE

Using this GEANT4 software one can simulate real time scintillator detector behaviour. A nuclear

detector can be characterized with respect to its external construction and experimental behaviour

for given radiation input.

We have considered three different parameters to characterize the GaN scintillator detector

behaviour, the dopant study and the detector thickness.

A. Dopant Study

Figure 3. Energy Band structure of an activated crystalline scintillator

Dopants are required to raise the energy of excitation of the electrons so that light output will

become measurable.

Types of Dopants for GaN

For GaN scintillator detector the various dopants under study are Europium, Indium, Cerium,

Silicon, etc.

Using GEANT4 software we can simulate the effect of these dopants with the base scintillating

material GaN with respect to the number of counts in the peak region. The result is tabulated as

below:

Dopant Total Counts Peak counts Peak to Total Ratio

Europium- Eu 36929 5250 14.21%

Indium- In 36707 4900 13.34%

Cerium- Ce 36714 4900 13.34%

Silicon- Si 36548 5150 14.09%

Table 1. Peak to total ratio of counts for different dopants for 1% doping

According to the above table Europium gives better peak to total ratio of counts as compared to

other preferred dopants.

Activator Excited States

Band Gap

Conduction Band

Scintillation

Photon

Valence Band




Advantages of Europium as a dopant:

1. Efficient red emission at 622nm used in electroluminescence devices.

2. It gives a relatively simple energy diagram

3. The optical transition between its ground state level and lowest emitting level provides important

information on different Eu3+ centres in the GaN lattice

Dopant Concentration

The following table shows the result of varying the dopant concentration on the count rate. The

dopant considered is Europium (Eu-63).

Dopant Concentration Total Counts

0.1% 36729

0.5% 36799

1% 36859

2% 37008

Table 2. Total counts for different concentrations of Eu as dopant

Thus, we see that increasing the dopant concentration has a direct effect on the total counts

obtained, although not linear. For our further experiments we have fixed dopant concentration to

1%.

B. Detector Thickness

Detector Construction

Figure 4. Energy Band structure of an activated crystalline scintillator

Detector Total Peak Peak to

Source

0.75”

2”

D

E

T

E

C

T

O

R


amplifier

103



Thickness Counts counts Total

Ratio

1” 90960 22734 24.99%

1.5” 130070 38659 29.72%

2” 169177 54584 32.26%

3” 327766 112974 34.46%

Table 3. Variation in peak counts with Detector Thickness

Thus we see that as the detector thickness increases the counts increase indicating that the

absorption of radiation is proportional to the detector thickness.

5. VOLTAGE PRE-AMPLIFIER DESIGN AND IMPLEMENTATION

Figure 5. Multisim Simulation of a Voltage Pre-Amplifier

Figure 6. Multisim Simulation Result of a Voltage Pre-Amplifier




Since Output of a Scintillator detector is in Voltage units, a Voltage Pre- Amplifier is used. The

circuit diagram of a Voltage preamplifier comprises of an emitter follower configuration for the BJT

which is required for driving the load. As output of PMT is in mV or V, no amplification is required.

6. CONCLUSION

The emerging need for finding alternative sources of energy has attracted many eyes to the nuclear

sector. The alarming effects nuclear radiation could have on human health, along with the necessity

of quantifying the results, within no time; nuclear detection has gained prime importance. These

factors have led to the above study.

Out of the various techniques available for detection my paper puts emphasis on Scintillator

detectors due to its striking features like High conversion efficiency, radiation hardness, etc.

One of the most recent scintillating materials under study is GaN. This detector setup has been

simulated using a GEANT4 software which is a low cost and safe solution for testing the results.

Also the electronic output has been tested using the Voltage preamplifier circuit which is simulated

using Multisim software.

As a future scope the output from GaN scintillator will be applied to the tested circuit and further

modifications will be done to the circuit to get desired output corresponding to energies for standard

sources of radiation.

REFERENCES

[1] William W. Moses, “Current trends in scintillator detectors and materials”, Nuclear Instruments

and Methods in Physics Research A 487 (2002) 123–128

[2] Glenn F. Knoll. “Radiation Detection and Measurement”, Third Edition

[3] Ei Ei Nyein1, Uwe Hömmerich, Chanaka Munasinghe, Andrew J. Steckl, and John M. Zavada,

“Excitation-Wavelength Dependent and Time-Resolved Photoluminescence Studies of Europium

Doped GaN Grown by Interrupted Growth Epitaxy (IGE)”, Mater. Res. Soc. Symp. Proc. Vol. 866 ©

2005 Materials Research Society

[4] Agostinelli.S, Allison.J, Amako.K, et.al. “Geant4- a simulation Toolkit”, Nuclear Instruments and

Methods in Physics Research A: Accelerators, Spectrometers, Detectors and associated

Equipment, 506(3)

[5] Instruction Manual on Scintillator Head, Shaping Amplifier, High Voltage Unit and MCA,

Electronics Coporation of India, Hyderabad.

[6] Principles of Radiation Detection, Nuclear Engg. Lab Manual.




PROPER HOMOTHETIC VECTOR FIELD FOR MAXIMAL SYMMETRIC TRANSVERSE SPACES

S. D. KATORE1, R. S. RANE2, S. S. DABHANE3 1PG Department of Mathematics, Sant Gadge Baba Amravati

University, Amravati 2Department of Mathematics, Y. C. Arts and Science College,

Mangrulpir 3Department of Mathematics, Dr. Sau. Kamaltai Gawai Institute of

Engg. & Tech., Darapur

Abstract

We study homothetic vector fields for maximal symmetric transverse spaces using direct integration technique. It is shown that above space-time admits proper homothetic vector field.

Key Words: Proper homothetic vector field, direct integration technique, maximal symmetric transverse spaces.

1. INTRODUCTION

Many authors have been examined different types of symmetries and its significant role in the

Einstein’s theory of general relativity[1,2]. Due to lack of linearity property, unlike Killing, affine

symmetry, conformal symmetry, homothetic symmetry is difficult to study[3-6]. Homothetic vector

field is very important to discuss the solution of Einstein’s field equations (EFE). Here four

dimensional, connected, Hausdorff space-time manifold with Lorentz metric of signature

is represented by . For any vector field on can be decomposed as

, (1.1)

where and are symmetric and skew-symmetric tensor on

manifold respectively. If

(1.2)

then X satisfies the equivalent conditions

, . (1.3)

106 S.D. Katore, R.S. Rane, S.S. Dabhane



Then is called a homothetic vector field on . If is homothetic and is non-zero Homothetic

constant, then it is called proper homothetic and it is Killing. The usual notations for covariant,

partial and Lie derivative are denoted by semicolon, a comma, and the symbol respectively.

In this paper we investigate the homothetic vector field of maximal symmetric transverse spaces

using direct integration technique.

2. HOMOTHETIC FIELD EQUATIONS AND THEIR RESULTS

Consider maximal symmetric transverse spaces in usual coordinates (t, r, θ, ϕ) with line element

, (2.1)

where

Using equation (1.3), we obtain the following homothetic field equations for (2.1)

(2.2)

(2.3)

(2.4)

(2.5)

(2.6)

(2.7)

(2.8)

(2.9)

(2.10)

(2.11)

Using equations (2.3),(2.4),(2.5) and (2.10) ,we get,

, (2.12)

, (2.13)

, (2.14)

. (2.15)

Proper Homothetic Vector Field for Maximal Symmetric Transverse Spaces 107



where , and are functions of integration. In

order to find (t, r, θ), and we need to solve remaining

six equations. Due to lengthy calculations here we will present results only. It follows that there exist

one possibility when above space-times (2.1) admit proper homothetic vector fields as

, , , .

where , , are constants.

In this case the space-time (2.1) takes the form

,

where and are non-zero constants. The proper homothetic vector fields in this case are

, , , .

where , ,

3. CONCLUSION

In this paper we have studied maximal symmetric transverse spaces according to their proper

homothetic vector field using direct integration technique. After examine all possibilities we found

that there is existence of proper homothetic vector fields and we get new metric for which

homothetic vector fields have been determined.

REFERNCES

[1] Stephani, H., Kramer, D., MacCallum, M.A.H., Hoenselaers, C. and Hearlt, E., Exact Solutions of Einstein’s Field Equations Cambridge University Press, 2003. [2] G.S.Hall, Symmetries and Curvature structure in General Relativity, World Scientific, 2004.

[3] R.F.Bilyalov, Sov,Physics, Vol. 8, 1964, pp. 878-880.

[4] L.Defrise-Carter, Commun.Math.Physics, , Vol. 40, 1975, pp. 273-282.

[5] G.S.Hall, J.Math.Physics, , Vol. 31, 1990, pp. 1198-1207.

[6] Michael Steller, Ann.Geom, , Vol. 29, 2006, pp. 293-311.




POKA-YOKE AUTO CHECKING SYSTEM FOR B-PILLAR ASSEMBLY COMPONENT

P.V. BHAMARE1, DR. RAJIV B2, MR. B. N. SADAVARTE3

1M.Tech. Student,

2Associate Professor,

Production & Industrial Engineering Dept., College of Engineering, Pune - 411005

3Director Disha Engg and Automation, 25/2, Near CDSS,

Erandawane, Pune, 411005

Abstract

Poka-yoke is a Japanese improvement strategy for mistake-proofing to prevent defects (or nonconformities) from arising during production processes. Poka-Yoke is a preventive action that focuses on identifying and eliminating the special causes of variation in production processes, which inevitably lead to product nonconformities or defects. This paper presents an approach for an automated assembly checking system of B-Pillar component, whether the assembled object are present in the given place or not. The system provides a fast inspection of objects and makes a necessary programmable decision. According to the inspection result of the entire assembled object the respective bulb of that object will response. If there is absence of any object then respective object bulb will not be glow and after the 5 sec Buzzer will start. As per the Indication of Buzzer the worker comes to know that assembled components are either missing or misplaced. There are total six no of assembly component and for detection of that component six no of photoelectric switches are used. One Optical Sensor is used for presence of B-pillar component on the Poka-Yoke. The necessary programmable action is taken form PLC (Programmable logic Controller). Key Words: Poka-Yoke, B-Pillar, PLC. 1. INTRODUCTION

Mechatronics is a branch of science where mechanical, electrical, electronics, and IT should be

considered together in the design stage itself to obtain a compact, efficient and economic

product rather than designing the components separately, which has proven many advantages

in today life. Similarly the industrial automation provides many sophistications & good quality

productivity with electronics, e.g. filling the bottles in the pharmaceuticals industry, printing on

bottle or on tablet boxes is being done automatically with very high speed. The robotics

assembly of a car in automobile industry & material handling in industry with conveyor belts,

management of wear housing & the car parking in market place, video capturing of sensitive

POKA-YOKE Auto Checking System for B-Pillar Assembly Component 109



area is also the major revolution in electronics with automation of conveyor belt, for

transposition of a job, the inspection of jobs assembly also very important. In today’s

competitive world any organization has to manufacture high quality, defect free products at

optimum cost. The new culture of total quality management, total productive management in the

manufacturing as well as service sector gave birth to new ways to improve quality of products.

By using various tools of TQM like KAIZEN, 6 sigma, JIT, JIDCO, POKAYOKE, FMS etc.

organization is intended to develop quality culture.

In early years during inspection of the assembly product was checked and selection and

rejection is done conventionally. Initially this process was manually done by worker but now due

to industrial revolution and automation it is done automatically. Due to automation the chances

of occurrence of error reduces and appropriate product get selected .Thus product quality

increases and expenses can also be lessen. The result is that product quality increases and

decreases the overheads on the product thus the cost of product decreases.

2. RELATED WORK P.R. SenthilMurugan [1] is to design a Mechatronics system to monitor the dimensions of the

product (clevis) using the pneumatics system with the help of Programmable Logic Controller

(PLC).The clevis is placed in the clevis holder, which is used to hold the work piece tightly. Then

the pneumatic cylinders which are controlled by PLC XE 102 extend and retracts based on the

ladder logic diagram. The calibrated gauges are attached in the pneumatic cylinders, if the

GO/no GO gauge travels smoothly inside the hole, it can be concluded that the dimensions of

the hole is in accordance to the specified standard dimensions. This system improves the

dimensional inspection and also eliminates the human errors and can be done at lower cost. R.

B. Nirmal & R. D. Kokate [2] presents sequence detection and monitoring system for geared

shaft assembly based on programmable logic controller (PLC) technology. PLC based assembly

system which recognizes that the worker has to pick up washers, gears, guide sleeves, circlip

etc as per the pre-defined sequence. All sensor output fed to Controller and it will detect the

sequence if it is ok then operation complete indicator will turn glow. If sequence is not follow it

will not process next operation. Main advantage of system is that system is very effective in

preventing defects from being passed to next process which reduces Reworks, Scrap, and

Wrong shipments. Ganesh B.Shinde, Vishal P.Ghadage [3] present hoe to describe the initial

steps in the implementation of PLC based auto weighing control system for automation industry.

110 P.V.Bhamare, Dr. Rajiv B., B.N. Sadawarte



3. B-PILLAR COMPONENT

Fig 1: B-pillar Component with assembled object.

This is the B-pillar Component of upcoming four wheeler of Mahindra. It included the six

assembled component as indicated in the figure 1. The project task is to find out that all six

component is present in proper place or not and if they are not present take a necessary

programmable decision to minimizes the error, increase accuracy and minimizes the time

required.

4. BLOCK DIAGRAM OF THE SYSTEM

Fig 2: Block Diagram of System

Assembly Components




A. OPTICAL SENSOR

A proximity sensor is a sensor able to detect the presence of nearby objects without any

physical contact. A proximity sensor often emits an electromagnetic or a beam of

electromagnetic radiation (infrared, for instance), and looks for changes in the field or return

signal. Specification: Operating Distance: 3 feet, Operating Temperature: -14° to 158° F (-

10° to 70° C), Power required: 3.3 to 15 VDC @ 40 mA, Standard Cable: 8 feet (2.4 m).

Fig: Optical Sensor

B.PHOTOELECTRIC SWITCH

A photoelectric switch is a device used to detect the distance, absence, or presence of an object

by using a light transmitter, often infrared, and a photoelectric receiver. They are used extensive

ly in machinery, textile, metallurgy, tobacco, railway, war industry and so on. There are three diff

erent functional types: through beam (opposed) retroreflective, and diffused type (proximity

sensing).

Fig: photoelectric Switch




C.PLC

PLC is the heart of our project. Optical sensor, photoelectric switch, and the auto cycle and

emergency switch connected to the input module and output module of PLC is connected to

pneumatic cylinder and indicators. [4]& [5] The Programmable Logic controller is solid state

equipment, designed to perform the function of logical decision making for Industrial control

applications. The PLC acts as a total replacement for hard wired relay logic with an effective

reduction in wiring and panel size; and of course, with increase in flexibility and reliability. It has

been experienced that majority of the faults with systems using PLCs are due to external

causes like, malfunctioning of field or external devices such as sensors, limit switches, push

buttons etc. The programming application allows entry and editing of the ladder-style logic.

Generally this software provides functions for troubleshooting and debugging the PLC software,

for example, the portion which is highlighted the logic to show the current status during

operation or by simulation. PLC program that is ladder diagram programs are typically written in

a special application or software on a personal computer then downloaded this file by a direct-

connection cable or over a network to the PLC.

D. INDICATOR

Indicators are used to show whether the job is reject or accept by the pneumatic cylinder. There

are total Six no indicators and one Buzzer. The no of indicators is same as no of inspected

assembly component. The buzzer will indicate if the system gives warning to the worker that

something going wrong.




5. FLOWCHART

Fig: Flowchart of the Process




6. SCHEMATIC REPRESENTATION OF SYSTEM

Fig 3: Schematic representation of project




7. PROTOTYPE MODEL OF SYSTEM

Fig 4: Prototype model of the System

8. OPERATIONAL FLOW

1) Operator will put component on the resting pad or fixture.

2) After that component automatically sense by the optical sensor and after 2 sec

component will be clamped by two pneumatic cylinders.

3) Press auto cycle button.

4) Sensor holding unit will came forward by the pneumatic cylinder.




5) If there are all assembled component are present then all respective indicator bulb

will glow.

6) Then punching cylinder will came forward and punch component then sensor holding

unit will retract and cylinder will declamped.

7) End of the cycle.

8) If there is any assembly objects are absent then after 5 sec buzzer will start and red

indicator bulb will glow.

9) The absent object indicator will not glow and declamped is not possible and sensor

holding bracket as it is unless and until operator will push Emergency Switch.

10) After reset, declamped and sensor holder retract then assembled the missing part.

11) Then remove the B-Pillar, Assembled the missing part and reinsert the part on the

system and check it by the next cycle.

9. ADVANTAGES OF THE SYSTEM

1) Enhanced Productivity.

2) The highest level of quality can be achieved.

3) Find errors and correct mistakes - where they occur.

4) Reduce Reworks, Scrap, and Wrong shipments.

5) Flexible configuration allows for maximum efficiency.

6) Accuracy and Speed is more.

7) Faster Control Action.

8) Programming of ladder is short and easy.

10. CONCLUSION

In industry the production speed should be high because the demand of the product is more.

But when we inspect the object manually then it will take more time for inspecting the

component and overall speed the production will decrease. So by using this POKA-YOKE auto

checking co system we totally overcome this problem. Indicating 30% increase in production.

With this monitoring system error will be detected while processing which results in zero

rejection. Despite the simplicity of the method used, this system presents: Higher efficiency.

Lower operating cost. Accuracy in monitoring. Thus, this system proved to be a versatile and

efficient Control tool in an automobile industrial application.




ACKNOWLEDGMENT

I owe many thanks to many people who helped and supported me during the execution of this

project. My deepest thanks to Dr. Rajiv B. the guide of project and Mr. B .N. Sadavarte for

giving me the opportunity to doing Internships in their company .Both the guide are guiding and

correcting various technical details and documents of mine with attention and care. They have

taken pain to go through the project and make necessary correction as and when needed.

REFERENCES

[1] P.R. Senthil Murugan Programmable Logic Controller based Mechatronics System for

Metrological Inspection of Clevis.

[2] R. B. Nirmal & R. D. Kokate PLC based Sequence detection & monitoring system for geared

shaft assembly International Journal of Electronics, Communication & Instrumentation

Engineering Research and Development (IJECIERD).

[3] Ganesh B.Shinde, Vishal P.Ghadage PLC Based Auto Weighing Control System

International Journal of Engineering and Technical Research (IJETR) ISSN: 2321-0869,

Volume-3.

[4] Introduction to Programmable Logic Controllers” Cengage Learning-India edition-Garry

Dunning-3 rd Edition-2012.Page 33-54,141-149.

[5] Programmable Logic Controller” s-John W .Webb.Ronald A. Reis- 5 th Edition-

2009.page38-40.




PROTEO: A NEW APPROACH TO NETWORK-ON-CHIP

AATRAY KUMAR SINGH

ELECTRONICS (VLSI & EMBEDDED SYSTEM) MIT ACADEMY OF ENGINEERING

PUNE 412105

Abstract

The purpose of this paper is to present the basic ideas behind the development of our Network-on-Chip (NoC) architecture, called Proteo. The system designers are moving into higher abstraction levels and usage of reusable IP (Intellectual Property) blocks is increasing. The communication between the IP blocks is of increasing importance and thus also be designed in a reliable and fast way. One proposed solution to this problem is to use Network-On-Chip (NoC) architectures, which are built up from reusable interconnect IP blocks. In this paper an interface router IP for Proteo network is introduced and implemented. The network implements packet switching in a hierarchical topology. A NoC needs a considerable amount of resources that can be shared with other system level tasks, like power saving and fault tolerance mechanisms.

1. INTRODUCTION As the feature dimensions scale down to deep submicron regime (below 0.25 m) the integration

density is not limited by the individual feature sizes e.g. of circuit metallization layers, but by

electrical phenomena, capacitive and inductive crosstalk between the interconnect lines. These

effects will have a great impact in maximum operating frequency and power consumption. In this

environment, communication within logic blocks will still be synchronous, but between them it will

become asynchronous in order to solve the problem of clock skew and delay. This is the Globally

Asynchronous Locally Synchronous (GALS) paradigm. In the System-on-Chip (SoC) designs of

the future there will be hundreds of functional IP blocks and a large amount of embedded Dynamic

Random Access Memory (DRAM) in a single chip. Communication requirements in this kind of

systems are very demanding, because each of those IPs can communicate in Gbit/s range. Due to

increased communication requirements the traditional bus-based solutions are not useful anymore,

thus new kind of communication architectures must be developed. One proposal to solve the

communication paradigm in SoC designs is to use NoCs, which are built up from reusable IP

blocks. These networks are scalable because there can be as many Intellectual Property (IP)

blocks as needed connected into the network, without dramatic problems in wiring delays,

capacitance, clocking etc. The global interconnects need to be treated as similar IP blocks as

processor cores or embedded memories. New flexible and configurable communication channel

architectures need to be identified. These communication channels will not form dedicated buses

Proteo: A New Approach to Network-on-Chip 119



as currently implemented on-chip and on PCBs, due to noise and scalability speed constraints.

Thus, the overall communication scheme will resemble more computer networking than traditional

bus based design. The paper is organized as follows: Section 2 provides the reader with a

practical understanding of the Proteo network. Then section 3 is dedicated to the architecture of

the proteo network on chip. Then in Section 4 the interface router is explained in more details.

Section 5 is dedicated to the synthesis results of the router and Section 6 for the reconfigurable

noc design. Then section 7 provides the protocols for the proteo noc. Eventually sections in 8,

conclusions are drawn and also the present limitations of this router and future research are

discussed.

2. PROTEO NETWORK ON CHIP

The NoCs are constructed from several basic building blocks, like routers or switches, bridges,

links etc. The routers are used to route packets from one place to another. The IP blocks are

also connected into them through some fixed interface. The bridges can connect several sub-

networks together and the links are used to connect all building blocks together. Characteristics

of the network used are strongly depending on how these basic blocks are implemented. This

paper presents a flexible layered interface router IP implementation of the network router for the

Proteo NoC. Proteo network is an on chip packet-switching network, which is developed in TUT

to solve communication problems of the future SoCs. Proteo can be seen as a set of

interconnection IP, which connects functional IPs together.

The Proteo network is constructed from two kinds of blocks: interface router IP and bridge IP.

The interface router IPs are used to connect functional IPs to the network and bridge IP is used

to connect several sub-networks together. An example network is shown in Fig. 1. In this

example there are three sub-networks connected together with two bridges. Nodes with two input

output link pairs have been used in sub-network 1, of which topology is a bi-directional ring.

Topology of the other sub-networks can be selected freely. Possible topologies are for example

different kinds of trees and meshes. There can be also other sub-networks behind these sub-

networks. Proteo does not restrict the complexity of the network topology. The Proteo NoC

supports several different kinds of communication protocols, network topologies and packet

formats. The Proteo NoC is described on two different abstraction levels. This paper

concentrates on the low-level model of the interface router IP. These models are used for logical

implementations, as well as to estimate physical properties like area, latency and delays of the

Proteo network. There are also high-level models of Proteo building blocks, used for

performance estimations and simulations of the larger networks. More detailed description of

Proteo architecture, its protocol, packet formats and different kind of building blocks can be found

in.

120 AATRAY KUMAR SINGH



Fig. 1: Example Network.

3. THE PROTEO ARCHITECTURE

The architecture of our system is discussed at a more physical level.

A. Overview

The basic hardware elements in our network are hosts, nodes and links. Every host will be

connected to the network using a dedicated node as a wrapper. Our nodes present a VSIA

compliant interface. This standard specifies three different downwards compatible Virtual

Component Interfaces (VCI):peripheral (PVCI), basic (BVCI) and advanced (AVCI). Links and

nodes are available as part of a library. They include parameters to customize their number of

channels and dimensions, their interface options, supported data sizes and protocol features,

based on requirements of functionality, throughput and Quality of Service (QoS).

Our target domain is that of heterogeneous systems, with many different types of IPs co-working

in the same chip. The system is divided in clusters, using a hierarchical network. This will

comprise multiple subnets with different performance, topologies, packet formats, etc. The

subnets are typically point-to-point structures, so each link can be effectively tuned to its

individual traffic requirements.

B. Topologies




Currently, the topology being explored is a hierarchical network built from a system-wide

bidirectional ring and several subnets with star (or bus) topology (Fig.2). The use of regular

topologies allows easy routing and direct replication of blocks throughout the system.

The connection of a host to the main ring or to a subnet depends on the available information at

the host interface level: stars are formed with BVCI elements, while blocks implementing the

AVCI interface can be attached directly to the ring. An interesting property of stars is that they

allow the presence of several BVCI initiators in the same cluster, which is not supported directly

by the standard.

Fig. 2: Example topology.

In the star topology well define two types of node: the satellite, which wraps in packets the

information presented at its interface, and the hub, which keeps track of the pending transactions

and routes the packets from node to node, while connecting the star to the rest of the network.

The ring nodes are essentially homogeneous, implementing different features depending only on

the needs of the hosts attached to them.

C. Hardware Elements

The architecture of a typical node is inspired in SCI standard, which is a standard interface

developed for multiprocessor systems. SCI implements a rich set of mechanisms covering most

of the needs of high performance systems. Our node architecture extends the basic SCI

architecture to allow a configurable number of dimensions and channels (Fig.3 and 4).




Fig. 3: Basic node architecture.

We have chosen a highly modular structure that makes easy its configuration and tuning. Links

provide a high level interface, so they are effectively treated as modular elements and

independently tuned. It must be easily modifiable and extensible, so we can use it to compare

the behavior of different design choices.

It must be relatively lightweight, so that large networks can be simulated. As we develop a

synthesizable version of the different blocks, we should be able to back annotate the information

we gather from the physical implementation in the high level model. Models at other levels of

abstraction can be easily co simulated, for example synthesizable blocks. We could use the

model for verification of the final design.

Fig. 4: Extended node architecture with three I/O links and

two channels in the first link.




4. STRUCTURE OF INTERFACE ROUTER IP

The basic structure of the interface router IP consists of one incoming link and one outgoing link.

This approach allows Fig. 5: Structure of the router IP. only one-directional communication in a

simple ring topology. If the designer wishes to use bi-directional communication or more complex

topologies, the basic structure is duplicated and the interface router IP is constructed from

several layers. This layered approach allows us to build up networks with different kind of

topologies. The interface router IP with two layers and two input-output link pairs is presented in

Fig. 2.

The interface standard used defines that there can be two different kinds of actors in

communication, called initiator and target. The initiators can generate requests to the target and

the target can only respond to these requests. Because of this definition we must also design two

different kinds of interface router IPs. The basic structures of both routers are similar to each

other. Because Proteo is a re-usable and flexible communication network there has to be a well-

defined interface to connect different kinds of functional IP blocks into it. The interface used

between interconnection IPs and functional IPs is Virtual Component Interface (VCI), which is

defined by VSI Alliance.

Fig. 5: Structure of the router IP.

The VSI Alliance defines three different versions of the VCI, Peripheral Virtual Component

Interface (PVCI), Basic Virtual Component Interface (BVCI) and Advanced Virtual Component

Interface (AVCI). Currently Proteo network supports BVCI and AVCI standards. The

implementation in this paper uses BVCI. The interface is used to generate Proteo packets from

VCI standard signals when the functional IP sends data into the network and on the other end it

will extract those signals from packets.




There are several FIFOs in each interface router IP. Those FIFOs are called Output, Input and

Bypass FIFO. All the

FIFOs are generic register banks and they are used to store packets. The Output FIFO is used to

store packets from the functional IP block to the network. The packets that have been sent are

stored in the Output FIFO until the interface deletes them from there. Before deleting, the packet

can be sent again if the interface is requested to do so. The Input FIFO is used to store packets

from the input link to the interface and the By Pass FIFO is used to store packets which are

bypassing the interface router. The Input and By Pass FIFOs are simple FIFO buffers without

any kind of re-send capabilities. The Input FIFO is a little different from the By Pass FIFO,

because the Overflow Checker can delete the start of the packet from it if the entire packet does

not fit into it. The Multiplexer and De-Multiplexer blocks are used to handle traffic between the

interface block and different layers. These blocks are left out in case when there is only one layer

in the interface router IP. The Multiplexer block is used to direct packets from the Input FIFOs to

the Interface. It checks the status signals from Input FIFOs and if there is a packet in some FIFO

it will tell that to the Interface. After the Interface has read the entire packet from the FIFO the

Multiplexer starts checking FIFOs again. The De-Multiplexer block reads packets from Output

FIFO, detects their destination address and according to a routing table it routes packets to the

correct Distributor block.

The Greeting block receives packets from the previous node. First it detects the packets

destination address. Then

it compares the destination address to its IP block address and if they are equal it writes the

packet to the Input FIFO through the Overflow Checker. If the addresses are not equal it writes

the packet to the By Pass FIFO. The Overflow Checker block receives packets from the Greeting

block. This block is used to check the contents of the packet. The Overflow Checker also checks

that the entire packet fits into the Input FIFO. In case that the Input FIFO becomes full in the

middle of the packet the Overflow Checker controls the Input FIFO so that the start of the packet

is deleted. When the Overflow Checker deletes a packet from the Input FIFO it will also generate

a Re Send packet to the sender IP block. The Re Send packet will take care of the re-

transmission of the original packet.

The Distributor block is used to transmit packets to the output link from the FIFOs. The

Distributor waits as long as there is a packet in some FIFO and then transmits one packet from

that FIFO. The priority of the FIFOs can be changed very easily, but in default the highest priority

is for the ByPass FIFO, next priority is for the Overflow Checker and the lowest is in the Request

FIFO. This default priority secures that the network traffic through the interface router is not

delayed. Also more complex arbitration schemes can be implemented.




5. PROTOCOLS

If the communication needs are characterized correctly, we can enable/disable protocol features

at each node. Just a basic packet format has to be defined and kept throughout the network

(Fig.5).

Fig. 6: Generic packet format.

In the stars the transactions can be split or not, depending on the interfaces involved (PVCI or

BVCI). The requester places its request at the node interface. The node converts it to packet

format. The star-hub takes this packet and delivers it to the target node, while logging in an

internal table the start of the transaction. Given that these basic interfaces don’t support out-of-

order responses, the next packet presented by the target node will be sent to the first pending

requester in the list for that node. In this way well allow the use the PVCI and the BVCI in multi-

requester environments. When the target of the transaction is not in the star, the star-hub adds

the extrain formation needed to the packet and forwards it to the ring.

In the ring, transactions are split and out-of-order responses are allowed. The AVCI-interface

presented by the blocks

attached to the ring provides more information about the transaction, like node, thread and

packet identifiers. The nodes can be made quite simple and still form complex networks,

because their functionality is restricted to the lower levels of the protocol stack.

6. PERFORMANCE

There are several methods how the performance of the network can be estimated. There are

several things that affect to total performance figures, like maximum clock frequency, latency

through the synchronous parts, etc. Maximum allowed clock speed is estimated from the

synthesis results. In this technology the maximum achievable clock frequency is 1GHz. Latency




of the interface router IP can vary a lot depending on the current status of the network. The

latency through the router can be quite small if there is no packet in the Output FIFO. On the

other hand if the Distributor is just sending a packet from the Output FIFO the bypassing packet

must wait in the By Pass FIFO until the packet is sent.

Minimum latency of the bypassing packet is four clock cycles, when the maximum latency can

be calculated as in (1).

Imax=4+ PL/WW............................ (1)

In (1) PL defines the maximum packet length in bits and WW defines the word width in bits. The

latency figures from the input link to the functional IP block and from IP block to the output link

are very similar to each other. Typical latency in these cases is similar to the maximum latency of

the bypassing packet. Total performance of the network can be also estimated with different

kinds of test cases. In the test case the network is used to handle traffic caused by some test

program, this kind of test cases can be found from.

7. CONCLUSIONS AND FUTURE RESEARCH

The future of highly integrated systems is pointing at a network-on-chip solution to the problems

of interconnection, productivity and heterogeneity. We are trying to extend our NoC proposal to

the fields of testing, fault tolerance and low-power techniques. The synthesizable interface router

IP block for Proteo NoC implementation was presented. The presented interface router IP is

constructed from several layers. The interface router IP can be used to implement packet

switching NoC architectures with different kinds of topologies.

Implementation of the interface router does not restrict the complexity of the network topology.

The interface router

IP uses VCI interface standard to connect the functional IP blocks into the Proteo network. The

interface router IP was designed using VHDL and it was synthesized with Synopsys and 0.18mm

standard cell technology. The achieved area and performance figures were also presented. The

area figures show that onchip communication can be handled with Proteo network with tolerable

area penalty. Future plans include: demonstrate the feasibility of complex hierarchical networks

using our approach, obtain estimates of network and protocol performance by means of

simulations and finish the implementation of the basic set of building blocks and gather low level

statistics.




REFERENCES

[1] David Siguenza-Tortosa, Jari Nurmi”Proteo: A New Approach to Network-on-Chip”, IEEE

Oct,2002

[2] Avi Kolodny”Networks on Chips (NoC) Keeping up with Rents Rule and Moores Law”, IEEE

March 2007

[3] Kangmin Lee, Se-Joong Lee, and Hoi-Jun Yoo,”Low-Power Networkon- Chip for High-

Performance SoC Design” IEEE 2006.

[4] Benini, L., De Micheli, G.: Networks on Chip: A New SoC paradigm. IEEE Computer 35(1),

January 2002, pp. 70-78.

[5] Robbe Vancayseele, Brahim Al Farisi, Wim Heirman, Karel Bruneel and Dirk

StroobandtRecoNoC: a Reconfigurable Network-on-Chip,. IEEE,2010

[6] P. Guerrier and A. Greiner, ”A Generic Architecture for On-Chip Packet-Switched

Interconnections”, Proc. Design, Automation and Test in Europe (DATE) 2000, 250-256.

[7] A. Hemani, A. Jantsch, S. Kumar, A. Postula, J. O berg, M. Millberg, and D. Lindqvist,

Network on a chip: An architecture for billion transistor era, in Proceedings of the 18th IEEE

NorChip Conference. IEEE, November 2000.

[8] Sonics micronetwork: Technical overview. http://www.sonicsinc.com/Pages/ Networks.html.

[9] SystemC website. http://www.systemc.org/.




FinFET TECHNOLOGY: A REVIEW

ABHIJIT B. DALVI MIT Academy of Engineering Alandi(D), Pune, 412105

Abstract

Right from the beginning till today, Planar technology has gone through huge amount of scaling. Today’s state-of-the-art Process technologies have minimum feature size of the order of few tens of nm. For example 45nm, 28nm.Though technology scaling is providing advantage in terms of Speed, other effects because of very short device geometries are becoming prominent and have posed a question or kind of brought a limit on further scaling of Planar CMOS technology. This brought in a major change in MOS device structure itself. People have started looking for alternative structures of MOS devices and are also looking for different technologies like CNT to continue further scaling and to Moore right. This paper tries to review one such technology called FinFET. It is MOS device with change in structure. In this paper we will see the structure of the device and also see how this new device structure tackles problems posed by conventional Planar Technology.

Key Words: MOS devices, CNT

1. INTRODUCTION

Since the advent of semiconductors and throughout the long history of designing integrated circuits

for everything from computer hardware to multifunction mobile devices, the basic tenet of Moore's

law has remained the same: the number of transistors on a given area of silicon doubles every two

years. Between the foundries developing advanced process nodes and their consumers' insatiable

demand for more functionality, the industry has fulfilled Moore's Law. The transistor count on

today's advanced multi-core processors is reaching the 3billion range, a long way from the 6800

processor of the mid 1970s that had just 5000 transistors[1].

Digital CMOS ICs rely on how well a MOS device acts as switch. Ideal switch has infinite

resistance in OFF state and zero resistance in ON state. Practical switch should have very high

OFF resistance and very low ON resistance.MOS device behaves quite well as a switch when

device geometries especially its length is high. But when length starts to shrink many short channel

effects come into picture and switch level behaviour starts degrading. This is what is being seen in

current nanometer technologies. This deviation is mainly because of sub-threshold characteristics

are affected by scaling. When sub-threshold characteristics approach characteristics after

threshold, then device no more acts as switch, it acts as resistor.In MOS device channel region is

FinFET Technology: A Review 129



controlled by Gate voltage. Device performance is defined by how much influence gate has on

channel area. As influence of gate decreases, leakage from source to drain increases which in turn

degrades OFF resistance[4].

New MOS device structure explained in here, provides greater control over channel region, by

controlling it from multiple sides. Multiple device structures are proposed which provide greater

control over channel region. FinFET belongs to a class of Multigate Devices or MuGFETs. One

more process technology called Ultra Thin Body SOI is also a competitor with FinFET technology.

In this paper structure of finFET and its effect over performance is reviewed. FinFET technology

currently supports gate lengths of 14 to 16nm. The main advantage of FinFET is that, finFETs can

be fabricated using conventional CMOS process technology.

2. STRUCTURE AND ELECTRICAL BEHAVIOUR

The graph shown in Fig.1 shows ID vs VGS for varying device sizes. As device sizes shrink

leakage increases and therefore we get higher values of IOff and when it tends to be almost equal

to ON state current of device, switch behaviour is lost. Device starts acting as resistor. To reduce

IOff and improve sub-threshold slope, better control over channel is required. This can be achieved

if we control channel from multiple side, which is main idea behind finFETs.

Fig. 1. VI characteristics for varying device geometries

130 Abhijit B. Dalvi



Fig. 2. Planar Vs finFET device structures

Fig.2 shows FET in Planar and FinFET technology. As can be noticed from figure, source and

drain regions are lifted upwards, they are taller and thinner. In finFET gate wraps around the thin

fin from multiple sides as compared to only one top side in planar technology.

In MOS device, influence of Gate over channel is limited to very small region near gate. Remaining

region is uncontrolled and charge leaks through these regions. In finFETs, Since channel region is

very thin and controlled from both sides, we get better OFF and ON resistance and lesser IOff

values. Fig.3 depicts different multi-gate structures including fin-FET device.

Fig. 3. Multigate Device Structures

Yellow colored region is channel. Region shown by purple colour is Oxide and Pink Colour shows

Bulk region. As can be noticed from finFET structure in Fig.3 gate is on three sides of channel

region separated by thin Oxide layer. However, thickness of oxide on top side is more as

compared to sides. This is done to improve electrostatics of device. That is why finFETs are

double gate devices. The ideal structure for FET will look like GAA-Gate All Around structure with

gate wrapping fully aroung channel region as shown in fig.3.But fabrication of such a structure is

quite difficult, so people resorted to finFET or TriGate Structures[2].




3. TECHNOLOGY

This section lists some important aspects of finFET fabrication. Fig.4 shows a cross sectional view

of a fabricated FIN.

Fig. 4. Formation of a fin

Formation of fin includes following steps.

1. Deep trenches are dug into Silicon bulk.

2. Trenches are filled with Oxide.

3. Some extra oxide from trenches is etched back to reveal fin Structure.

As device structure is changed effective width is addition of two fin heights and fin width. This

might help in achieving higher integration density, but is limited by fin pitch which is distance

between adjacent fins[1].

132 Abhijit B. Dalvi



Fig.5 shows 22nm finFET fabricated by Intel.

Gate is wrapping aroung number of fins can be easily seen. Each fin is an individual MOS

transistor. Dimensions of Fins and spacing between them are not in control of designer, as

compared to planar process. This means that, device widths cannot be varied continuously and

they are discrete.

4. CHALLENGES

1. Reducing Fin height variability is a major challenge. Using SOI over process partly eliminates

this problem, but is costlier.

2. Problems related to double patterning come into picture. Double patterning increases number of

Fabrication steps and this variability. It include variation parasitics because of misalignment.

Effects of double patterning must be considered while RC extracting circuits.

3. Design rules have become quite complicated.

4. Since device geometries shrink, electromigration increases.




5. CONCLUSIONS

In this Paper we reviewed finFETs and tried to compare it with Planar MOS device. Following

conclusions are drawn.

1. FinFETs have better I-V characteristics as compared to device of same size in Planar

technology.

2. FinFETs are easy to scale and can be fabricated using same planar CMOS processes.

3. FinFETs can be fabricated over bulk or SOI.

Double Patterning is used in this technology as device geometries and spacing are quite small.

REFERENCES

[1] Guillorn, M. ; Chang, J. ; Bryant, A. ; Fuller, N. ; Dokumaci, O. ; Wang, X. ; Newbury, J.;

Babich, K. ; Ott, J. ; Haran, B. ; Yu, R. ; Lavoie, C. ; Klaus, D. ; Zhang, Y. ; Sikorski, E. ;

Graham, W. ; To, B. ; Lofaro, M. ; Tornello, J. ; Koli, D. ; Yang, B. ; Pyzyna, A. ; Neumeyer, D.

Khater, M. ; Yagishita, A. ; Kawasaki, H. ; Haensch, W. , FinFET performance advantage at

22nm: An AC perspective, Symposium on VLSI Technology, 2008 , pp. 12-13

[2] Hisamoto, D. ; Wen-Chin Lee ; Kedzierski, J. ; Takeuchi, H. ; Asano, K. Kuo, C. ; Anderson,

Erik ; Tsu-Jae King ; Bokor, J. ; Chenming Hu, FinFET-a self-aligned double-gate MOSFET

scalable to 20 nm, IEEE Transactions on Electron Devices, 2000, Volume: 47, Issue: 12 , pp.

2320-2325

[3] Swahn, B. ; Hassoun, S. Gate sizing: finFETs vs 32nm bulk MOSFETs, 43rd ACM/IEEE

Design Automation Conference, 2006, pp. 528 - 531

[4] Jurczak, M. ; Collaert, N. ; Veloso, A. ; Hoffmann, T. ; Biesemans, S., Review of FINFET

technology, IEEE International SOI Conference, 2009 , pp. 1 - 4

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Preface to the 6 - ISCA 978-93-84648-83... · 2017-07-30 · 2015 International E - Publication , Preface to the 6th National Conference The Department of Engineering Sciences, MIT