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Ch1. Information SystemsIntroduction and Concepts

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1. Introduction• Information systems have become the backbone of all

kinds of organizations today.- manufacturing, education, health care, government, and

all businesses large and small ex)travel agency, tracking inventory, family doctor- You are expected to do...

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2. Information Systems• Information- To communicate from one agent to another- knowledge or beliefs of agents- To (data) objects that represent knowledge /beliefs

- An IS is an artifact for efficiently managing information items

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• There exist many views to define what is different between Information Systems and Information Technology.

• The classic view is to consider an information system as a system to manage information.

• In this book, we accept the fact that the term “information system” may refer to only the computerized part of an organization but that it may also refer to the entire organization using information technology to support business processes.

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3. Types of Information Systems• The main focus of this

course is on organizational information systems.

• Six elements- Customers- Products & Services- Business Process

- Participants- Information- Technology

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Some representative IT applications list

a. Enterprise Resource Planning(ERP) Systemsb. Procurement Systemsc. Manufacturing Systemsd. Sales and Marketing Systemse. Delivery Systemsf. Finance Systemsg. Product design Systemh. Workflow Management Systemsi. Data warehouses

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4. The different phases of the development Process• We can differentiate development processes by how they

are working - ex) SAP;• Variety of life-cycle models- Life-cycle model focusing on management perspective- Initiation- Development- Implementation- Operation and maintenance

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The waterfall and spiral models are two classical life-model.Developing models is an essential part of the analysis and the design phase.

- A model describes the product to be designed in a certain form.

- Only the purpose of the model is important.

- In general, models can be abstract descriptions or specifications.

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• Analysis Phase• Design Phase- Functional design model- Construction model• Implementation Phase• Further Life-cycle Phases- Production Phase, Distribution Phase, Deployment Phase, Maintenance Phase• Final Remarks

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5. System Concepts• Discrete dynamic systems- Dynamic Systems; a state that is subject to change- Discrete Systems; Systems that change their state in

discrete jumps

• State and State Space- State; all things that may change and whose change is

relevant for the system should be represented.- State Space; the set of all possible states- Ex) S={1,2,3,4,5} S={(1,0),(1,1),(1,2)…}

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• Transitions and Transition Systems- Transition; A transition is an ordered pair (x, y) where x and y

are elements of the state space S, that is, x, y S∈- If there are only some of elements, we can draw the state-

transition diagrams as a graph

• Process Paths and the Behavior of a System- We need to consider more complicated processes rather than a

single one.- Which states can be reached from a given initial state of the

system?- The initial state of a system is the state in which a system

starts its operations.- A reachable state is a state which the system can reach after

zero or more transitions.

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- The set of all possible process paths from a given initial state is called the behavior of the system

- In the behavior of a transition system two special cases are possible.

a. A situation where no further transition can be made. b. The situation where from every state at most one transitions is possible• The design Perspective and the Simulation Perspective- The design perspective may be adopted to model an

artificial system to be developed- The simulation perspective may be adopted to model and

simulate natural system

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6. Preview• We have seen both small and large state spaces.• Several other kinds of models for discrete dynamic

systems have been proposed.• S(state space) represents the statiscal aspects of the

system and a transition relation TR with.• Modeling methods for IS have two components that

information model and process model• Information model + Process model =System model

which is the counterpart of the state space.