Chapter 12 Information Systems and System Development What Is an Information System?

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Nov 13, 2013 (3 years and 8 months ago)

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Chapter 12

Information Systems and System Development

What Is an Information System?



System

a collection of elements and procedures that interact to accomplish a goal.



Information

system

a system used to generate information to support users in an
organiz
ation.



System development

the process of designing and implementing a new or
modified system.


Who Uses Information Systems?




Executive managers: strategic decisions.



Middle managers: tactical decisions.



Operational managers: decisions related to meeting s
hort
-
term objectives.



Non
-
management workers: on
-
the
-
job decisions.


Types of Information Systems



Different types of information systems are used by different workers.



Office systems



Office

automation

computer
-
based office
-
oriented technologies.



Office sy
stems

combinations of hardware, software, and other resources used to
facilitate communications and enhance productivity.



Document
-
processing systems



Communications systems



Transaction processing systems



Order
-
entry systems



Inventory control systems



Payrol
l systems



Accounting systems



Management information systems (MISs)

provide decision
-
makers with
preselected types of information.



Generally provide information in the form of computer
-
generated reports.



Usually generated from data obtained from transactio
n processing systems.



Most frequently used to make moderately structured, middle
-
management
decisions.



Decision support systems

(DSSs)

help managers organize and analyze the
information when making decisions.



Provide information on demand and incorporate
data from both internal and
external sources.



Are tailored to help with specific types of decisions and are typically used by
middle and upper management.



A special type of DSS targeted to upper management is called an
executive
information system (EIS)
.



Geographical information systems (GISs)



Combines geographical information with other types of data to provide a better
understanding of relationships between the data.



Commonly used to make decisions about locations (e.g. new facility locations,
disaster r
isk, geographical crime patterns).




Enterprise
-
wide system

integrates an entire company or enterprise.




Inter
-
enterprise system

links multiple enterprises, such as a business and its
customers, suppliers, and business partners.



Types of enterprise systems:



Electronic data interchange (EDI)

transferring data between different
companies using a network.



Enterprise resource planning (ERP)

ties together all types of a business’s
activities.



Enterprise application integration (EAI)

exchanges ERP or other interna
l
system data between different applications and organizations.



Customer relationship management (CRM)

customer service activities; many
take place online today

via the Web.



Supply chain management (SCM)

oversees materials, information, and
finances from
supplier to the consumer.



Value chain management



Just
-
in
-
time (JIT) systems



Product life cycle management (PLM)

and
price optimization systems.




Design and manufacturing systems



Computer
-
aided

design (CAD)



Computer
-
aided

manufacturing (CAM)




Artificial int
elligence (AI)



Turing Test



Chess programs




Artificial intelligence systems



Natural language systems

can understand natural languages (e.g.
chatterbots
).



Expert systems

make decisions based on an expert knowledge base and
predetermined rules.



Neural

networ
k

systems

connections between processing elements resemble
brain neurons.



Robotic systems

use
robots
.


Responsibility for Systems Development



The information systems (IS) department



Data processing personnel



Systems analyst



Programmers



Operations personn
el



Design group



Outsourcing companies



Advantages: Cost savings, flexibility



Disadvantages: Less control, conflicts with in
-
house personnel


The System Development Life Cycle (SDLC)

Preliminary Investigation



Also called a
feasibility

study



Purpose: To ident
ify and evaluate the program area to suggest possible courses of
action.



Documentation: Feasibility report


System Analysis



Purpose: To study the problem in depth and determine the needs of the system
users.



Data collection.



Data analysis (data flow diagra
ms, decision tables, checklists, etc.).



Documentation: Questionnaires etc. used during data collections and diagrams
generated during data analysis.


System Design



Purpose: To develop a model of the new system and perform an analysis of expected
benefits a
nd cost.



System model.



System flowcharts



Input/output diagrams



Data dictionary



Cost/benefit analysis (tangible and intangible benefits).



Documentation: System specifications.


System Acquisition



Purpose: To purchase or develop the hardware and software nec
essary for the new
system.



The make
-
or
-
buy decision.



RFPs and RFQs.



Evaluating bids.



Documentation: RFPs, RFQs, proposals received, a
nd vendor evaluation materials.


System Implementation



Purpose: To install the system and make it operational.



Conversion o
ptions:



Direct conversion



Parallel conversion



Phased conversion



Pilot conversion



Documentation: Implementation schedule and test data and results.


System Maintenance



Purpose: To keep the system operational until the next major system redesign.



Post
-
implem
entation review.



Updating software and hardware, as needed.



Documentation: Completed project folder.


Approaches to System Development



Traditional approach

standard six phases in that order.



Prototyping

first develop and modify a
prototype
of the system.



End
-
user development

system designed and implemented by the end user.



Key Terms

Accounting system


Artificial intelligence system


Benchmark test


Computer
-
aided design (CAD)


Computer
-
aided manufacturing
(CAM)


Customer relationship management
(CRM
)


Decision support system (DSS)


Electronic data interchange (EDI)


Enterprise application integration
(EAI)


Enterprise resource planning (ERP)


Enterprise
-
wide system


Expert system


Geographic information system
(GIS)


Information system


Inte
r
-
enterprise system


Inventory control system


Just
-
in
-
time (JIT) system


Management information system
(MIS)


Natural language system


Neural network


Office automation (OA)


Office system


Order entry system


Payroll system


Preliminary investi
gation


Prototyping


Robot


Robotics


Supply chain management (SCM)


System acquisition


System analysis


System design


System development


System development life cycle
(SDLC)


System implementation


System maintenance


System


Systems analy
st


Traditional system development


Transaction processing system


Value chain management