Upload
stacy
View
19
Download
2
Embed Size (px)
DESCRIPTION
Welcome to CMPE003 Personal Computer Concepts: Hardware and Software. Winter 2003 UC Santa Cruz Instructor: Guy Cox. Assignments. Assignment #6 – The Last One Due March 12, 2003 Spreadsheets – (MS Excel) Generate a monthly budget spreadsheet. - PowerPoint PPT Presentation
Citation preview
Welcome to CMPE003 Personal Computer Concepts: Hardware and Software
Winter 2003UC Santa Cruz
Instructor: Guy Cox
January 23, 2003 2
Assignments
Assignment #6 – The Last One Due March 12, 2003
Spreadsheets – (MS Excel) Generate a monthly budget spreadsheet
http://www.soe.ucsc.edu/classes/cmpe003/Winter03/hw6_spreadsheet.html
January 23, 2003 3
Final Project
Due no later than March 19, 2003 You can turn in earlier..
Power Point presentation 4 pages Extra points for special effects, animations
Turn in on a floppy/CDROM
http://www.soe.ucsc.edu/classes/cmpe003/Winter03/finalproject.html
Systems Analysis and
Design:
The Big PictureChapter 15
January 23, 2003 5
Objectives
Define the terms system, analysis, and design Describe the principal functions of the systems
analyst List and describe the phases of the systems
development life cycle Describe the various data gathering and analysis
tools Describe a selection of systems design tools Explain the concept of prototyping Explain the role of the maintenance task in the
systems development life cycle
January 23, 2003 6
Systems Analysis and Design: What is it?
System organized set of related components
established to accomplish certain task Natural Systems
Cardiovascular system Planned and placed by people
Water system Computer system
A system that has computers as one of its components
January 23, 2003 7
Systems Analysis and Design: What is it?
Systems analysisProcess of studying an existing system to determine how it works and how it meets user needs
Systems designProcess of developing a plan for an improved system, based upon the results of the systems analysis
January 23, 2003 8
Systems Analysis and Design: Why do it?
Impetus for change Internal force, e.g. improved productivity and
efficiency External force, e.g. meet regulatory
requirements or resolve customer issues Authority for change
Approval of higher management
January 23, 2003 9
Systems Analyst
Professional computer employee who performs analysis and design
Change agent Overcome reluctance of users to change
Typical career path Programmer Programmer / Analyst Systems Analyst
January 23, 2003 10
Systems Analyst: Functions
Coordination Schedules and system-related tasks Personnel
Manager Programmers Users Vendors of computer equipment Mail room employees Contractors
January 23, 2003 11
Systems Analyst: Functions
Communication Oral presentations Written documentation
Planning and design Plans and designs the new system Involved from beginning of project through final
implementation of the system
January 23, 2003 12
SDLC: Systems Development Life Cycle
Preliminary investigation Analysis Design Development Implementation
January 23, 2003 13
SDLC: Preliminary Investigation
Feasibility study / System survey Determine the problem Describe the problem Understand management decisions
Organizational chart Informal hierarchy
Produces rough plan and what to do
January 23, 2003 14
SDLC: Preliminary Investigation
Problem Definition Nature of the problem
Separate problem from symptoms of problem
Scope of the projectEstablish boundaries..
Budget and schedule Objectives of the project
What user thinks system should do
January 23, 2003 15
SDLC: Preliminary Investigation
ReportWhat you have found
Recommendations
Financially feasible
January 23, 2003 16
SDLC: Preliminary Investigation
Resulting Management Decision Drop Fix a simple problem Authorize the analysis phase
January 23, 2003 17
SDLC: Analysis
Understand the existing system Gather data Analyze data
Establish system requirements
January 23, 2003 18
SDLC: Analysis – Data Gathering
Written documents Interviews
Structured Unstructured
Questionnaires Observation
Visits by appointment Participant observation
Sampling
January 23, 2003 19
SDLC: Analysis – Analyze Data
How the current system works Determine system requirements Basis for documentation Tools
Data flow diagram (DFD) Decision tables
January 23, 2003 20
SDLC: Analysis – Data Flow Diagram
January 23, 2003 21
SDLC: Analysis –Decision Tables
January 23, 2003 22
SDLC: Analysis – System Requirements
Detailed list of things the system must be able to do
Design is based upon system requirements Agreement upon requirements is needed
before proceeding
January 23, 2003 23
SDLC: Analysis – Report to Management
Summarize problems Describe requirements Cost analysis Recommendations for next step Obtain authorization to proceed
January 23, 2003 24
SDLC: Design
Planning the new system System Architecture Two Design Phases
Preliminary design (or external design) Detail design (or internal design)
January 23, 2003 25
SDLC: Preliminary Design
Major system aspects Centralized or distributed Online or batch PC-based? How will input be
captured? Necessary reports
January 23, 2003 26
SDLC: Preliminary Design
Make or buy decision Packaged software
Meet at least 75% of requirements? Change business procedures for part or all of remainder? Customize for part of all of remainder?
Custom software Programmers write code
Outsourcing System is developed by external organization
January 23, 2003 27
SDLC: Preliminary Design
Create an overall plan Offer alternatives that meet requirements Explain differences Evaluate costs
January 23, 2003 28
SDLC: Preliminary Design
Build a prototype Limited working system of subset
Does not need true functionality Output looks like anticipated system output
Working model that can be modified and fine-tuned Uses high-level software tools – CASE Best for small-scale systems
January 23, 2003 29
SDLC: Preliminary Design
CASE toolsComputer-Aided Software
Engineering Supports specific analysis and design tasks Integrated environment that supports the
entire systems development process
January 23, 2003 30
SDLC: Preliminary Design
Presentation All alternatives Selected plan Prototype of the system Obtain authorization to proceed
January 23, 2003 31
SDLC: Detail Design
Parts of detail design phase Output requirements Input requirements Files and databases Systems processing Systems controls and backup
January 23, 2003 32
SDLC: Detail Design
Output requirements Medium Type of reports Contents
January 23, 2003 33
SDLC: Detail Design
January 23, 2003 34
SDLC: Detail Design
Input requirements Medium Content Input forms Validation Volume
January 23, 2003 35
SDLC: Detail Design
Files and Databases Organization Access Format of records Coordinate with database administrator
regarding external databases and updating
January 23, 2003 36
SDLC: Detail Design
Flowchart Symbols
January 23, 2003 37
SDLC: Detail Design
January 23, 2003 38
SDLC: Detail Design
Systems Controls and Backup Insure that input is processed correctly Prevent fraud and tampering System journals Backup of system files
January 23, 2003 39
SDLC: Detail Design
Report to Management Detailed design specifications report Presentation Obtain authorization to proceed
January 23, 2003 40
SDLC: Development
Doing the work to bring the new system into being
Scheduling
January 23, 2003 41
SDLC: Development
Programming Refine the design Detailed logic flowcharts and pseudocode
Testing Unit testing System testing Volume testing
January 23, 2003 42
SDLC: Implementation
Converting to the new system Training Equipment conversion File conversion System conversion Auditing Evaluation Maintenance
January 23, 2003 43
SDLC: Implementation – Training
Begin during testing User’s manual (Technical Writers) Hands-on Training consideration
Space Equipment Data User’s schedules
January 23, 2003 44
SDLC: Implementation – Conversion
Equipment Planning Installation of new equipment
File Manual to electronic Special programs to convert old format to new
January 23, 2003 45
SDLC: Implementation – Conversion
System Direct conversion Phased conversion Pilot conversion Parallel conversion
January 23, 2003 46
SDLC: Implementation –Auditing
Audit trail Trace output back to source
January 23, 2003 47
SDLC: Implementation – Evaluation
Working? Meets original requirements? Benefits Meets budget Improvements
January 23, 2003 48
SDLC: Implementation – Maintenance
Ongoing activity for life of system
January 23, 2003 49