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IE412 INDUSTRIAL QUALITY TOOLS

QUALITY

TOOLS

1. Interview a fifth year currently undertaking at least one thesis – Systems Engineering, Industrial Research Project, Design Project and/or Project Feasibility. Ask him/her about the primary difficulty faced by his/her team in the conduct of their theses. Identify the reasons why they faced such difficulty. Create a diagram to present these gathered data.

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CAUSE AND EFFECT DIAGRAM: Helps user to understand and list out all possible causes and effect or desired effect Provides the framework for channelizing and coming out with causes (or recommendations) quickly

and effectively

2. Consider that you are a marketing manager of Siomai ni Maimai, a fast growing siomai delivery business with eleven stalls in Cebu City. After four months of operation, Siomai ni Maimai felt the pinch of decline in its sales. Repeat orders were no longer evident. You chose OJT students from the IE Department of CIT to find out the reasons for the sales decline in order that this situation can be corrected immediately. Construct a diagram to diagnose as to which reason/s the management should focus their efforts on. See table for data.

Type of Customer Complaint

No. of Complaints

Late deliveries 55Wrong quantity delivered 106Incorrect type of siomai delivered 23

Taste 19Cold siomai upon delivery 118Others 39

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Type of Customer Complaint

No. of Complaints Percentage Cumulative

Percentage

Cold siomai upon delivery 118 32.78% 32.78%Wrong quantity delivered 106 29.44% 62.22%

Late deliveries 55 15.28% 77.50%Others 39 10.83% 88.33%

Incorrect type of siomai delivered 23

6.39% 94.72%Taste 19 5.28% 100.00%

TOTAL 360 100.00%  

PARETO CHART: Helps identify the problems in the organization that cause the greatest loss of profit Good management tool to use in prioritizing action plan

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Cold siomai u

pon delivery

Wrong quantity deliv

ered

Late deliverie

s

Others

Incorre

ct typ

e of siomai d

elivered

Taste0.00%

40.00%

80.00%

120.00%

04080120

Cumulative Pareto Chart of Customer Complaints of Siomai ni Maimai

No. of Complaints cumulative

3. Draw a cellphone (of whatever model) that has been used for a long time. Identify the locations with which the scratches can be found. Make a report which also includes the following: date of inspection, number of scratches, name of inspector, and/or comments.

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4. The following data represent the number of customer complaints in Siomai ni Maimai every month of its operation for the past five years. Construct a frequency distribution starting with the lowest number of customer complaints. Construct a diagram that can possibly show the shape of its distribution. (To recall, the steps in constructing a frequency distribution is shown below the array.)

9 34 14 33 23 19 16 15 19 13

21 23 28 8 23 23 24 23 17 22

26 27 30 14 30 27 47 38 29 38

16 29 32 22 14 20 20 29 25 18

24 35 29 39 16 33 30 24 31 35

22 11 22 23 12 33 23 19 19 9

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FREQUENCY DISTRIBUTION DIAGRAM: Power tool for elementary analysis of data that contain variations

Exhibits the number of data points that fall within a given cell or class interval

1. k = 1 + 3.3221 log n k = 1 + 3.3221 log 60 k = 6.91 k 7 2. R = Highest Value – Lowest Value R = 47 – 8 R = 39

3. w = R / k w = 39 / 7 w = 5.57 w 6

4. First class UL: 8 First class LL: 8 + 5 = 13

Class Limits Tally Frequenc

y8 – 13 |||||-| 6

14 – 19 |||||-|||||-||| 13

20 – 25 |||||-|||||-|||||-||| 18

26 – 31 |||||-|||||-|| 12

32 – 37 |||||-|| 738 – 43 ||| 344 – 49 | 1

    n= 60

8 – 13 14 – 19 20 – 25 26 – 31 32 – 37 38 – 43 44 – 4902468

101214161820

Number of Customer Complaints (monthly) of Siomai ni Maimai

class interval

FREQ

UENC

Y

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5. The table shows the results in a metal fabrication company in Liloan whereby a pyrometer is used to determine the temperature of fire in melting metal ingots as these are formed into metal carcass. The number of defects refers to the bubbles, discoloration, and brittleness found in every sample of twenty items. Construct a diagram that illustrates how the number of defects is possibly affected as the temperature increases.

Summary Check sheetTemperature

(oC)No. of

Defects145.0 11145.5 11146.0 13146.5 16147.0 24147.5 26148.0 29148.5 31149.0 33149.5 34150.0 33

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SCATTER DIAGRAM: Helps in analyzing the relationship between two variables