Faculty of Arts Atkinson College ITEC 1010 A F 2002 Welcome Seventeenth Lecture for ITEC 1010 3.0 A Professor G.E. Denzel.

Faculty of ArtsAtkinson College

ITEC 1010 A F 2002

Welcome

Seventeenth Lecture for ITEC 1010 3.0 A

Professor G.E. Denzel


ITEC 1010 A F 2002

Agenda Continue the discussion of Artificial Intelligence Begin discussion of Project Development and

Systems Analysis (today through the SDLC)


ITEC 1010 A F 2002

More on Expert Systems Strengths

Rapid, consistent problem solutions

Ability to justify and explain reasoning

Easy to replicate and distribute to non-expert users

Limitations Can only solve

problems in a narrow domain

Can only be applied to certain problem types

Cannot learn from its experience

Hard to acquire knowledge from human expert


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Other Intelligent Systems Natural Language Processing

The ability to communicate with a computer in your natural language• Voice (speech) recognition and speech

understanding – system recognizes spoken words and understands their meaning

• Voice synthesis – computer produces natural language voice output that sounds ‘human’


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Other Intelligent Systems Neural Computing

A computer model that uses architecture that mimics certain brain functions

Performs pattern recognition well Can analyse large data sets and discover

patterns where rules were previously unknown Can ‘learn’ by analysing new cases and

updating itself Many potential business applications


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Figure 11.2 Neural Internet-based optical character recognizer.


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More Neural Nets

Discussion of using Neural networks to predict the stockmarket --- why not?


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Other Intelligent Systems Case-Based Reasoning

Uses solutions from similar problems and adapts them to new problems

Useful in solving very complex cases Fuzzy Logic

Enables systems to effectively deal with uncertainty

Often use in combination with other technologies to improve productivity


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Rules for a Credit Application (Could be from neural net or expert system)

Mortgage application for a loan for $100,000 to $200,000

If there are no previous credits problems, and

If month net income is greater than 4x monthly loan payment, and

If down payment is 15% of total value of property, and

If net income of borrower is > $25,000, and

If employment is > 3 years at same company

Then accept the applications

Else check other credit rules


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Intelligent Agents Software agent that autonomously performs

tasks on behalf of a user with certain goals or objectives Can tirelessly perform repetitive tasks over a

network Includes knowledge base and ability to learn Can be static (on the client only) or mobile

(move throughout a network) Often used to facilitate search and retrieval on

the Internet and to assist in e-commerce tasks


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Examples of Agents in use today

Search engines (yahoo, google, alta vista, Ask Jeeves, etc.)

Stock trackers http://www.botspot.com


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Virtual Reality Simulation of a physical environment in a

highly realistic way Useful for communication and learning Many potential business applications,

especially marketing Think of CAE, world leader in flight

simulators


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Intelligent Systems Concerns Potential to use the power of intelligent

systems in unethical ways Who will be accountable for decisions

made by intelligent systems? Who ‘owns’ knowledge and expertise?

Can an expert be ‘forced’ to reveal his/her expertise?


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Chapter 14 PreviewIn this chapter, we will study:

Planning process for IS application development The process of developing systems as outlined in the

SDLC Alternatives to the SDLC and why they are useful Ways to obtain applications from outside the organization Methods that are useful in developing Internet/intranet

applications


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Information Systems Planning Process

IS Development ProjectsIS Development Projects

Organization Mission

Organization Mission

Business AssessmentBusiness

Assessment

Organization Strategic PlanOrganization Strategic Plan

Current Information Technology Architecture

Current Information Technology Architecture

IS Strategic PlanIS Strategic Plan

New Information Technology ArchitectureNew Information Technology Architecture

IS Operational PlanIS Operational Plan


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IS Strategic PlanObjectives

Align with the organization’s strategic plan Provide for an IT architecture that enables users,

applications, and databases to be seamlessly networked and integrated

Allocate IS development resources efficiently among competing projects, so the projects can be completed on time, within budget, and have required functionality

Issues - efficiency; effectiveness; competitiveness


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IS Operational Plan Mission - the mission of the IS function IS environment - the summary of the information needs of

the functional areas and of the organization as a whole Objectives - the IS function’s current best estimate of its

goals Constraints - technological, financial, and personnel

limitations on the IS function Long-term systems need - a summary of the processes

needed by a company and the IS projects selected to support them and reach organizational goals

Short-range plan - an inventory of current projects, and a detailed plan of projects to be developed or continued during the current year


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SDLC - (Systems Development Life Cycle) the development method used by most organizations today for large, complex systems, in some form.

Systems Analysts - IS professionals who specialize in analyzing and designing information systems

Programmers - IS professionals who modify existing computer programs or write new computer programs to satisfy user requirements

Technical Specialists - experts in a certain type of technology, such as databases or telecommunications, who help create information systems

Information Systems Development Terms


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The Traditional SDLC(1) Systems Investigation

(2) Systems Analysis

(3) Systems Design

(4) Programming

(5) Testing

(6) Implementation

(7) Operation

(8) Maintenance

Go Back to a previous Stage or Stop

An eight-stage systems development life cycle (SDLC)


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System Investigation Feasibility study determines the probability of success of

proposed system’s development project. Includes …• Technical feasibility (will we be able to build the

system?)• Economic feasibility (how much will it cost to build

the system and how much will it benefit us?)• Behavioral feasibility (if we build the system, will it

be accepted and used?)

Phases in SDLC (1)


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Systems Analysis Examines the business problem(s) that the organization

plans to solve with information systems Determines what the new system must do by examining:

• Strengths and weaknesses of the existing system

• Functions that the new systems must have to solve the business problem(s)

• User information requirements for the new system

Phases in SDLC (2)


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Systems Design Describes how the system will fulfill the user

requirements Develop both logical design and physical design Output => technical design or system specification…

• system outputs, inputs, and user interfaces• hardware, software, databases, telecommunications,

personnel, and procedures• how these components are integrated

Phases in SDLC (continued)


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Programming the translation of the design specifications into

computer code structured programming techniques improve the logical

flow of the program by decomposing the computer code into modules



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Figure 14.3 Flowchart diagram of a payroll application of structured programming.


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Implementation The process of converting from the old system to the

new system Four major conversion strategies

• Parallel conversion: the old and new systems operate simultaneously for a period of time

• Direct conversion: the old system is cut off and the new systems is turned on at a certain point in time

• Pilot conversion: introduces the new system in one part of the organization

• Phased conversion: introduces components of the new system in stages



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Testing Checks to see if the computer code will produce

the expected and desired results under certain conditions



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Operation the new system will operate for a period of

time, until it no longer meets its objectives

Maintenance (simultaneous with Operation) debugging the programs updating the system to accommodate changes in

business conditions adding new functionality to the system (which

loops back to the beginning of the SDLC)

SDLC Phases (cont’d)


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Prototyping Starts with only a general idea of user requirements, and

develops models of the system ‘until it’s right’

Advantages: Speeds up the development approach Gives the users the opportunity to clarify their information

requirements Useful in the development of decision support systems and

executive information systems

Disadvantages: Replaces the systematic analysis and design stages of the

SDLC - quality may be sacrificed Can result in an excess of iterations

Alternatives to the SDLC


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Joint Application Design (JAD) A group-based method for collecting user requirements

and creating staged designs

Advantages: Saves time Greater support for, and acceptance of new systems Produces higher quality systems Easier implementation Lower training costs

Disadvantages: Very difficult to get all users to JAD meetings All the problems that may be caused by any group

process



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Rapid Application Development (RAD) A method that can combine JAD, prototyping, and

integrated CASE tools, to rapidly produce a high-quality system

Advantages: Active involvement of users in the development process Speeds the development process Reduces development costs Can create applications that are easier to maintain and

modify

Disadvantages: May result in systems with limited functionality and

adaptability for change



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Integrated Computer-Assisted Software Engineering (ICASE) Tools Automate many of the tasks in the SDLC

Advantages: Produces systems with a longer effective operational life Speeds up the development process and result in systems that

are more flexible and adaptable to changing business conditions

Results in excellent documentation

Disadvantages: More expensive to build and maintain initial system Requires more extensive and accurate definition of user

needs and requirements Difficult to customize and may be difficult to use with

existing systems



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Use of Computer-Aided Software Engineering (CASE) Tools

CASE tools automate tasks required in a system development effort and enforces adherence to the SDLC Upper CASE tools

• Tools that focus on activities associated with the early stages of systems development

Lower CASE tools• Tools that focus on the later implementation stage of systems

development

Integrated-CASE (I-CASE) tools• Tools that provide links between upper- and lower-CASE

packages, allowing lower-CASE packages to generate program code from upper-CASE package generated designs


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Object-Oriented Development A fundamentally different view of computer

systems Advantages:

• Reduces the complexity of systems development and leads to systems that are easier and quicker to build an maintain

• Improves programmers’ productivity and quality• More flexible• Allows systems analysts to think as users do about the

system• Ideal for developing Web applications• Depicts the system in user terms, increasing

understanding of what the new system does and how it meets its objectives



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Object-Oriented Development Disadvantages

• Runs more slowly• Need to retrain the programmers in OO

methodology



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Development Outside the IS Department

End User Development Users perform ad hoc programming to solve business

problems Factors that drive the trends toward increased end-user

computing and end-user development• More powerful, inexpensive desktop hardware• Increasingly diverse software capabilities• Increasingly computer literate population• Backlog of IS projects• Apparent cost savings

End-users (usually) don’t produce adequate documentation or perform adequate testing

Security may be breached


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External Acquisition of Prewritten Software Factors to consider during make-or-buy decision

• On-time• On-budget• Full functionality• User acceptance• Favorable costs-to-benefits ratio• Low maintenance• Scalability• Integration with other systems• Minimal negative cross-impacts• Reusability



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Application Service Providers (ASPs) Software obtained via subscription Software resides on ASP’s systems Software is accessed via Web or VPN Subscriber does not have to host software on

existing computer systems Updates and bug fixes are provided by the ASP ASP can provide help-desk support



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Outsourcing Using third parties to provide some or all

functions and services of the IT department IT may not be a core competency of the firm;

better to hire outside specialists Advantages:

Outsourcer can obtain hardware capabilities less expensively due to economies of scale

Outsourcer can hire needed technical staff Outsourcer specializes in providing computer

services Ability to expense outsourcing fees provides tax

benefits



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Outsourcing (continued) Disadvantages:

• Economies of scale may be of limited value• Staffing depends on outsourcers needs, not client’s• Lack of familiarity with business/industry• Contract problems• Internal cost reduction opportunities could eliminate

the advantage of outsourcers Guidelines:

• Write short-period contracts or have flexibility since business needs are dynamic

• Use of subcontractors should be controlled• Use selective outsourcing only for those functions

where it makes sense



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Building Internet & Intranet Applications

Much future development will likely be Web pages due to their simplicity and ease of development

SDLC probably not followed due to simplified Web development

A Strategy for Internet/Intranet Development

Identify the objectives for organizational Web site(s) and pages

Include infrastructure requirements as well as security and legal issues in plans

Obtain/assign necessary personnel and provide oversight

Identify and prioritize potential projects


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Building Internet & Intranet Applications

JAVA - A Promising Tool Important programming language for putting

extra features into Web pages An object-oriented language designed for

implementation on networks Includes numerous security features to prevent

downloaded programs from damaging files or creating other problems on the receiving computer

Faculty of Arts Atkinson College ITEC 1010 A F 2002 Welcome Seventeenth Lecture for ITEC 1010 3.0 A Professor G.E. Denzel.

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