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Chapter Chapter 11

System ConceptSystem Concept

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Introduction to systemsIntroduction to systemsy System is based on Input-Process-Output (IPO

model). Manual work can be replaced by computerizedsystem for accuracy and speed of processing.

y System is a word derived from the Greek word¶Systema· which means an organized relationshipamong components.

y

A System may be defined as orderly grouping of interdependent components linked together accordingto a plan to achieve a specific goal. Each component isa part of total system and it has to do its own share of work for the system to achieve the desired goal.

y An Information system is an arrangement of people,data, processes, information presentation andinformation technology that interacts to support andimprove day-to-day operations in a business as well assupport the problem solving and decision making

needs of management and users.

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Figure 1 - Basic System Entity Construct

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System ComponentsSystem Componentsy A big system may be seen as a set of interacting

smaller systems known as subsystems or functionalunits each of which has its defined tasks.

y All these work in coordination to achieve the overallobjective of the system. System engineering requiresdevelopment of a strong foundation in understanding

how to characterize a system, product, or service interms of its attributes, properties, and performance.

y As discussed above, a system is a set of componentsworking together to achieve some goal. The basicelements of the system may be listed as: Resources

Data/Information

Intermediate Data

Processes

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System CharacteristicsSystem Characteristics

y Systems also exhibit certain features and

characteristics, some of which are:

Objective

Standards

Environment

Feedback

Boundaries and interfaces

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Classification of SystemsClassification of Systemsy Systems may be classified as follows:

y a) Formal or Informal

y b) Physical or Abstracty c) Open or Closed

y d) Manual or Automated.

a) A Formal System is one that is planned in advance and is usedaccording to schedule. In this system policies and procedures aredocumented well in advance. A real life example is to conduct a scheduledmeeting at the end of every month in which agenda of the meeting hasalready been defined well in advance.

y An Informal System is the system that is not described by procedures. Itis not used.

y According to a schedule. It works on as need basis. For example, Salesorder processing system through telephone calls.

b) Physical Systems are tangible entities that may be static or dynamic.

y Computer Systems, Vehicles, Buildings etc. are examples of physicalsystems.

y Abstract systems are conceptual entities.

y Example: Company

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c) Open System is a system within its environment. It receives

input from environment and provides output to environment.y Example: Any real life system, Information System, Organization

etc.

y Closed System: It is isolated from environment influences. Itoperates on factors within the System itself. It is also defined as aSystem that includes a feedback loop, a control element andfeedback performance standard

d) Manual andAutomated systems: The system, which does notrequire human intervention is called Automated system. In thissystem, the whole process is automatic.

y Example: Traffic control system for metropolitan cities.

y The system, which requires human intervention, is called a ManualSystem.

y Example: Face to face information centre at places like Railwaystations etc.

Classification of SystemsClassification of Systems conticonti....

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System users Conti«System users Conti«y External Users: Modern information systems are

now reaching beyond the boundaries of thetraditional business to include customers and otherbusinesses as system users.

y In business-to-business information systems, each

business becomes an external user of the otherbusiness·s information systems. For example, in thecase of direct purchasing of product through theInternet, customer becomes an external user of theretailer·s order processing information systems.

y Another example is that if a business connect theirpurchasing systems directly to the order processingsystems of their suppliers then both becomeexternal users to each other.

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ROLE OF A SYSTEMS ANALYSTROLE OF A SYSTEMS ANALYST

y The success of an information system development

is based on the role of Systems analyst. Amongseveral roles, some important roles are described

below

y ChangeAgent

y Investigator and Monitor

y Architect

y Motivator y Intermediary

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DUTIES OF A SYSTEMS ANALYSTSDUTIES OF A SYSTEMS ANALYSTS

The duty of a systems analyst is to coordinate the

efforts of all groups to effectively develop andoperate computer based information systems. The

duties of a systems analyst are following:

y Defining Requirements

y Prioritizing Requirements by Consensus

y Analysis and Evaluation

y Solving Problems

y Drawing up Functional Specificationsy Designing Systems

y Evaluating Systems

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Skills OF A SYSTEMS ANALYSTSkills OF A SYSTEMS ANALYSTy Analytical skills

x � System study

x �

Organizational knowledgex � Problem identification

x � Problem analysis and problem solving.

y Technical skillsx The technical knowledge of a Systems Analyst must be updated from

time to time

x Systems Analyst should be as familiar as possible with such families of technologies

y Management skillsx Resource management

x Project management

x Risk management

x Change management.

y Interpersonal skillsx Communication skills

x Working alone as well as in a team

x Facilitating groups

xManaging expectations.

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