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8/3/2019 IT5103 Lec02 Business Systems
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IT103 1
Business Systems
&Information Systems
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IT103 2
Business Systems
Before looking at business systems – let us
consider what jobs you can aim for in thecomputer industry.
Think about the jobs you have seen advertised.
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IT103 3
Why do we need to know about Business
Systems in a BInfoTech course?
As an IT Professional you may:
business systems in large and smallorganisations
plan
investigate analyse
develop
install
evaluate maintain
communicate with users of
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IT103 4
As an IT professional you need:
• a sound understanding of an organisation’s
business activities.
• a understanding of what businesses do.
• along with a good technical background.
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Understanding The Business
• Business Process Modeling
• Business Profile
• Business Models
– Business model
– Business process
– Business process reengineering (BPR)
5
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IT103 6
What is a Business?
“ a business is a combination of personnel,materials, facilities and equipment that
work together to achieve defined goals ”
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IT103 7
Business Activities
What businesses do you know of?
Now identify what business activity they are
engaged in.
Write down the name of a business or
organisation that you are aware of.e.g. Toyota
e.g. makes cars, trucks
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IT103 8
Types of Business
• Manufacturing companies
• Service companies
• Combined service and production companies• Government organisations
• Internet based companies (dot.coms)
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Understanding Type of Business
• New Kinds of
Companies
– Production-oriented – Service-oriented
– Internet-dependent
– Dot-com (.com)
– Brick-and-mortar
9
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Impact of the Internet
• E-Commerce or I-Commerce
• B2C (Business-to-Consumer)
• B2B (Business-to-Business)
– EDI
– Extensible markup language (XML)
– Supplier relationship management (SRM)
10
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IT103 11
Types of Businesses
For the companies named earlier, identify whichtype of business they are engaged in.
Toyota
Company Activity Type of Business
makes
cars,
trucks
Manufacturing
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IT103 12
All organisations use business systems.
A business system is often made up of a set
of interacting sub-systems or modules,
such as:
– purchasing – production
– marketing
– finance system – human resources
– receivables
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IT103 13
These subsystems communicate witheach other by the movement of dataeither as output data or input data.
e.g. What data would a payroll system need?
And where would it get this data from?
Employee name, hourly rate, hours worked ...
Human resources, employee timesheet …
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IT103 14
Information Systems
What are they?
“ … systems that combine: • hardware
• software• people• data• procedures
to achieve specific results thatsupport an organisation’s business
objectives ”
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Information System Components
• Hardware
– Is the physical layer of
the information system – Moore’s Law
• Software
– System software
– Application software
– Enterprise applications
15
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Information System Components
• Software
– Horizontal system
– Vertical system
– Legacy systems
• Data
– Tables store data
– By linking the tables, the system can extract
specific information
16
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Information System Components
• Processes
– Describe the tasks and
business functions thatusers, managers, and
IT staff members
perform to achieve
specific results
• People
– Stakeholders
– Users, or end users
17
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IT103 18
Investigating Information
Systems
An IT professional needs to understand:
– organisational levels – roles of personnel
– organisation charts
– corporate culture
– types of IS
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IT103 19
Organisational Levels
Operational staff
Lower management
Middle management
Top management
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IT103 20
Roles of Personnel
• Systems analysts – plans, analyses anddesigns and implements information
systems• Programmers – designs, codes, tests and
implements information systems
• Users – end users include employees,customers, suppliers, managers, technicians,sales force
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IT103 21
Organisation Charts
Are used to show:
• Department Names
• Job Titles/Roles
• Who reports to whom
• May include peoples names (but not always)
http://www.chartexample.com/chart_example/orgchart.php
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IT103 22
Organization Chart – An ExampleNuts and Bolts Company
Personal
Assistant
PlanningManager
Big BoltsCutter
Small BoltsCutter
Supervisor
Bolts Division
Supervisor
Nuts Division
Shop Floor
Manager
Distribution
Manager
ProductionManager
DirectorOperations
DirectorMarketing
DirectorHuman Resources
DirectorFinance
CEO
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IT103 23
Corporate Culture
• The set of beliefs, rules, traditions,values,and attitudes that define a company
and influence its way of doing business.• Mission statements contain clues about
corporate culture
• Analysts must understand this culture andhow it affects the way information ismanaged.
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IT103 24
Types of Information Systems
1. Enterprise Computing Systems - ERP
2. Transaction Processing Systems – TPS
3. Management Information Systems – MIS
4. Decision Support Systems – DSS5. Executive Information Systems – EIS
6. Knowledge Management Systems – expert
systems7. Office Systems
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How Business Uses Information
Systems• In the past, IT managers divided systems
into categories based on the user group the
system served – Office systems
– Operational systems
– Decision support systems – Executive information systems
25
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How Business Uses Information
Systems• Enterprise computing
systems
– Support company-wide
operations and datamanagementrequirements
– Enterprise resourceplanning (ERP)
– Many hardware andsoftware vendors targetthe enterprise computingmarket
26
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How Business Uses Information
Systems• Transaction
processing systems
– Involve large amountsof data and are
mission-critical
systems
– Efficient because they
process a set of
transaction-related
commands as a group
rather than individually27
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How Business Uses Information
Systems• Business support systems
– Provide job-related information to users at all
levels of a company – Management information systems (MIS)
– Radio frequency identification (RFID)
– What-if
28
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How Business Uses Information
Systems• Knowledge management systems
– Called expert systems
– Simulate human reasoning by combining aknowledge base and inference rules
– Many knowledge management systems use a
technique called fuzzy logic
29
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How Business Uses Information
Systems - DSS• used by management• what-if analysis, predictive
• analyses internal and external data
• systems may include: – statistical analysis modules
– database query languages
– spreadsheets
– graphics
– modeling tools
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7. Office Systems
• powerful systems made up of interacting sub-
systems
• office worker’s aids -> improve productivity,
communication and information sharing• may include - Internet, intranet, database
management, email, fax, voice-mail,
teleconferencing, WP, calenders, document
management, spreadsheets, DTP, presentation
graphics...
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Other Systems
• specialised information systems
– systems designed to handle special functions
eg. timetable scheduling in a school, insurance
billing in a hospital
• integrated information systems
– systems that combine elements of office
systems, MIS, DSS – systems that do not fit into any neat category
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How Business Uses Information
Systems• User productivity systems
– Technology that improves productivity
– Groupware
• Information systems integration
– Most large companies require systems that
combine transaction processing, businesssupport, knowledge management, and user
productivity features
33
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Information System Users and Their
Needs
34
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IT103 35
At different levels of the organisation:
• different types of decisions are made
• different types information are required
• different information systems are required
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IT103 36
What is a system?
By this definition, is the computer a system?
A set of interrelated components that work
together for a common purpose.
The Computer as a System
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IT103 37
What are the characteristics of a system?
Inputs
Outputs
Control
Boundaries
Feedback
From lecture 1:
By this definition, is the computer a system?
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IT103 38
Information System Components
The simple model of a system:
SYSTEM
INPUTS
OUTPUTS
can be re-labelled: Inputs can be called DATA
System becomes PROCESSING
Outputs become INFORMATION
DataProcessing
Information
S
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IT103 39
Information System Components
This simple model can then be expanded to include allthe components of an information system.
Data Information
Hardware
People
Procedures
Software Data
Processing
Summary -
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IT103 40
Summary
• Business systems
• Information systems
• The computer as a system
Reading:
Shelly Cashman Rosenblatt
• Chapter 1- Systems Development Life Cycle page19-24,
• Chapter 4 – Fact-finding page 160-165
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IT103 41
Information Gathering Techniques
Fact-Finding Techniques• Software developer normally uses several
fact-finding techniques during a software
development project including:examining documentation,
Interviewing staffs,
observing organization in operations,
research on business requirements,
questionnaires.
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IT103 42
Examining Documentation
• Can be useful:
– to gain some insight as to how the need for a
database arose;
– to identify the part of the organization
associated with the problem;
– to understand the current system.
E l f f d i
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IT103 43
Examples of types of documentation
that should be examined
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IT103 44
Interviewing
• Most commonly used, and normally mostuseful, fact-finding technique.
• Enables collection of information from
individuals face-to-face.• Objectives include finding out facts,verifying facts, clarifying facts, generatingenthusiasm, getting end-user involved,
identifying requirements, and gatheringideas and opinions.
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INTERVIEWS
Advantages of Interviewing.
A useful way of verifying information
May produce information from knowledgeable
people not otherwise available
Breaks down barriers and establishes personal
relationships
Shows interest in those most likely to be affectedby change and enlists their support
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IT103 46
INTERVIEWS
Disadvantages. There is A danger of 'leading' the interviewee
The interviewer may only hear what they want to
hear
Bias, prejudice and other psychological 'noises'
can hinder fact gathering
Information gained from an interview must be
verified from other sources
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IT103 47
Observing the Organisation in
Operation
• Effective technique for understanding system.
• Possible to participate in, or watch, a person
perform activities to learn about system.• Useful when validity of data collected is in
question or when complexity of certain
aspects of system prevents clear explanationby end-users.
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IT103 48
OBSERVATION
Advantages of Observation. First-hand knowledge is gained
Gives accurate information
Demonstrates actual conditions Can show variations in workloads occurring
during short periods
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OBSERVATION
Disadvantages Very expensive in analysts time
Time consuming - can hold up system development
Can antagonise staff unless handled very carefully
Analyst may not see the true picture (ie. Staff behaviour
may change while under observation)
Results need to be checked (by discussion / interview)
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IT103 50
Research
• Useful to research application and problem.
• Use computer trade journals, reference
books, and Internet (including user groups
and bulletin boards).
• Provide information on how others have
solved similar problems, plus whether or not
software packages exist to solve, or evenpartially solve the problem.
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IT103 51
RECORD SEARCHING
Advantages of stored data sources Establish quantitative information; volumes, frequencies,
trends, ratios
Can be A short cut to fact gathering
Do not depend on extensive staff cooperation Usually provide more reliable data
Task can be delegated
For some purposes they can be the cheapest method of fact
gathering
Data is formalised and standardised and needs little
verification or interpretation
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IT103 52
RECORD SEARCHING
Disadvantages. Documents eventually become out of date and of limited
use
Need to be selective - can be time consuming
Produce background information only
Do not give the complete picture
Cannot give information on attitudes, opinions
Can be expensive in terms of analysts time Often information not documented that only one person
knows how to do
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IT103 53
QUESTIONNAIRES
Advantages of Questionnaires. Can gather a lot of data very quickly
Can be precisely targeted
Are relatively cheap Are exactly repeatable
Take up a minimum of busy staffs time
Can be used anonymously
Allow the respondent time to think about their
answer
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IT103 54
QUESTIONNAIRES
Disadvantages.
Design is difficult
Often misunderstood
Danger of people only telling you what they think
you want to know
Analysis of results may take time and be costly
Normally A poor response rate which can give an
unrepresentative sample (20-30% return iscommonly considered good)
Nearly always A slow response rate