Chapter 11
System Development & Programming
Professor Michael J. Losacco
CIS 1110 – Using Computers
Overview
Chapter
11
Define System Development
List the System Development Phases
Explain Activities for Each Phase
Explain High- & Low-level Languages
Detail Steps of Program Development
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Information System
Chapter
11
Hardware
Software
Data
People
Procedures
Together Produce Information
Interact to Achieve Common Goal
3/44
System Development
Chapter
11
Phases
4/44
Guidelines
Chapter
11
Arrange Tasks Into Phases
Groups of Activities
Involve Users
Anyone for Whom System is Being Built
Develop Clearly Defined Standards
Sets of Rules & Procedures
Company Expects Employees to Follow
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Initiation
Chapter
11
Correct Problem in Existing System
Improve Existing System
Outside Group May Mandate Change
Competition Can Lead to Change
Request for System Services
AKA Project Request
Request for New / Modified System
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Participants
Chapter
11
Representatives from Departments
Involved in Building or Using System
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Project Management
Chapter
11
Project Manager
Plans, Schedules, & Controls Activities
Establishes Scope
Goals, Objectives, & Expectations of Project
List Required Activities
Time Required
Cost Estimate
Order & Dependency
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Project Success
Chapter
11
Successful
On-time, On-budget, All Features
Challenged
Late, Over Budget, Less Features
Failed
Cancelled or Delivered but Never Used
Standish Group 2009
9/44
Project Success
11
Smaller Projects Have Better Success
<$750K
$750K-3M
Budget
Chapter
$3-6M
$6-10M
$10M+
0%
10%
20%
30%
40%
50%
60%
Success
Standish Group
10/44
Project Success
11
Shorter Projects Have Better Success
60%
50%
40%
Success
Chapter
30%
20%
10%
0%
6
9
12
18
24
Months
Standish Group
11/44
Project Success
Chapter
Average Percentage Above Estimate
11
200%
Overage
150%
100%
50%
0%
1994
1996
1998
2000
2002
2004
Year
Time
Cost
Standish Group
12/44
Project Success
Chapter
11
Notable Project Failures
FAA Air Traffic Control
$1.5B – 1994
IRS Modernization
$3.4B – 1997
DoD Business Modernization
$19B – 2004
200 Inventory / 450 Personnel Systems
Children’s Hospital of Pittsburgh
Dramatically Higher Death Rates – 2002
13/44
Planning Phase
Chapter
11
Steering Committee
Decision-making Body for Company
Receives Project Requests
Function of Committee:
Review & Approve Project
Prioritize Requests
Allocate Resources
Form Project Development Team
14/44
Analysis Phase
Chapter
11
Preliminary Investigation
Determine Nature of Problem
Determine Whether it is Worth Pursuing
Feasibility Study
Economic
AKA Cost / Benefit
Operational
Schedule
Technical
15/44
Analysis Phase
Chapter
11
Detailed Analysis
Study How Current System Works
Determine User’s:
Wants
Needs
Recommend Solution
16/44
Analysis Phase
Chapter
11
Documentation
Collect & Summarize Data & Information
Reports
Diagrams
Programs
Other Deliverables
17/44
Analysis Phase
Chapter
11
Data & Information Gathering
Review Documentation
Research
Questionnaire
One-on-one interview
Observation
Joint-application Design (JAD) Session
18/44
Analysis Phase
Chapter
11
Process Modeling
AKA Structured Analysis & Design
Transform Inputs into Outputs
Entity-relationship Diagrams
Data Flow Diagrams
Project Dictionary
19/44
Analysis Phase
Chapter
11
Entity-relationship Diagram
Shows Connections Between Entities
Entities
Objects in System that Have Data
20/44
Analysis Phase
Chapter
11
Data Flow Diagram
Shows Flow of Data in System
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Analysis Phase
Chapter
11
Project Dictionary
Structured English
Used to Explain Details of Process
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Analysis Phase
Chapter
11
Project Dictionary
Decision Table / Tree
Logical Conditions & Actions
23/44
Analysis Phase
Chapter
11
Project Dictionary
Data Dictionary
Stores Details About Each Data Item
24/44
Analysis Phase
Chapter
11
System Proposal
Assess Each Alternative Solution
Recommend Most Feasible Solution
Steering Committee Has to Approve
ROI
Hard v. Soft
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Analysis Phase
Chapter
11
Possible Solutions
Packaged
Prewritten Software Available for Purchase
Horizontal
Meets Needs of Many Companies
Vertical
Designed for Specific Industry
Custom
Write Own Software
Outsourcing
Hire Outside Company to Perform Work
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Analysis Phase
Chapter
11
Outsourcing
Senior Resource Salaries
PayScale 2009
27/44
Design Phase
Chapter
11
Develop All Details of System
Write Technical Specifications
Details Functionality & Scope of Project
Request for Information (RFI)
Request for Quotation (RFQ)
Vendor Quotes Price For Listed Hardware
Request for Proposal (RFP)
Vendor Quotes Price For Software
Based on Specification
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Design Phase
Chapter
11
Acquire Hardware & Software
Solicit / Test / Evaluate Vendor Proposals
References from Vendor
Talk to Current Users
Demonstrations
Trial Version
Benchmark Test Measures Performance
Prototype (Proof of Concept)
Working Model of Proposed System
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Design Phase
Chapter
11
Acquire Hardware & Software
Turnkey Solution
Complete System Provided by VAR
Value-added Reseller
Purchases Products from Manufacturer
Resells Them, Offering Additional Services
Must Meet Certain Requirements
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Design Phase
Chapter
11
Inspection
Step-by-step Review of Deliverables
By Project Team & Users
Uses
Final Review of Specification
Before Submitted to Programming Team
Identify & Correct Any Errors
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Implementation Phase
Chapter
11
Build System & Deliver it to Users
Develop Programs
Test & Install
Train Users
Convert to New System
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Implementation Phase
Chapter
11
Develop Programs
Programmers Write Code to Specification
Follow Program Development Life Cycle
Analyze the Requirements
Design the Solution
Validate the Design
Implement the Design
Test the Solution
Document the Solution
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Implementation Phase
Chapter
11
Testing
Unit
Each Individual Program Works
System
All Programs in Application Work Together
Integration
Application Works With Other Applications
Acceptance
Verifies New System Works with Actual Data
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Implementation Phase
Chapter
11
Testing
Phases
Alpha
Performed by Employees
Beta
Performed by Customers
Training
Show Users How to Use New System
Scheduling Conflicts
35/44
Implementation Phase
Chapter
11
Convert to New System
Transition from Old to New System
Pilot Most Widely Used
36/44
Support Phase
Chapter
11
Ongoing Support After Implementation
Conduct Post-implementation Review
Perform Maintenance Activities
Identify & Correct Errors
Identify Enhancements
Monitor System Performance
Assess System Security
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Computer Program
Chapter
11
Set of Instructions
Directs Computer to Perform Tasks
Language
Set of Words, Symbols, & Codes
Communicates Instructions to Computer
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Languages
Chapter
11
Categories
Low-level Languages
Machine Dependant
Typically Determined by Processor
Machine & Assembly
Faster Execution, More Code Required
High-level Languages
Machine Independent
Third, & Fourth Generation
Slower Execution, Less Code Required
39/44
Program Development
Chapter
11
Development Options
Make (Create In-house)
More Control
Buy (Acquire from Software Vendor)
Lower Overall Cost
Higher Quality
Faster Implementation
Less Staff Required
40/44
Analyze Requirements
Chapter
11
Review Requirements
Meet with Systems Analyst & Users
Identify
Input
Processing
Output
Data
41/44
Design Solution
Chapter
11
Devise Solution Algorithm
Step-by-step Procedure to Solve Problem
Flowchart
Conveys Logic Graphically
Pseudocode
Uses Condensed English to Convey Logic
42/44
Implement Design
Chapter
11
Write Code
Translate Design into Program
Syntax
Rules that Specify How to Write Instructions
Comments
Program Documentation
Create User Interface
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Test Solution
Chapter
11
Ensure Program Runs Correctly
Error Types
Syntax
Logic
Run time
Debugging
Locate & Correct Syntax & Logic Errors
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