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Wednesday 31 August 2005

The professor went over the Microsoft free sofftware offerings for us. He noted that you can get a number of legal copies of windows.

Download Visio 2003 somehow. We will be using it in class.

He talked more about the evolution of IS in the Oil and Gas industry. We then did a diagram of a typical IS department.

Wednesday 07 September 2005

The modern systems development life cycle focuses more on the analysis phase than in the past. Past styles of design focused more on the development section of the life cycle. The shifts were from a code based cycle to a more planning based approach. He used a good example via a constructing a home story. The intent of the newer methodology is to reduce cost over the life of the system.

The Expert Paradox: The more you know how to do a particualar task, the less likely you can tell someone else how to do it. Three ways to stimulate memory:

  1. Brain Surgury
  2. Near death experience
  3. Associations (JAD)

The four basic steps are analysis, design, development and implementation. This class will focus on the first two parts.

JAD or joint application design/development, is used so that via memory associations the group becomes more than its parts.

Monday 12 September 2005

Feasibility Analysis

  • Feasibility is the measure of how beneficial or practical the development of an information system will be to an organization.
  • Feasibility analysis is the process by which feasibility is measured
  • Creeping commitment - measure feasibility througout the system development life cycle

Types of feasibility

  • Operational
  • Technical
  • Schedule
  • Economic
  • Legal / Contractual
  • Political

Operation Feasibility

  • The process of assessing the degree to which a proposed system solves business problems or advantage of business opportunities.
  • Issues
    • Link to business / information systems plan
    • Impact on organizational structures and procedures
  • PIECES Framework
    • Performance: adequate throughput and response time
    • Information: provide end-users and managers with timely, pertinent, accurate and usefully formatted information
    • Economy: adequate service level and capacity - reduce the costs of the business or increase the profits of the business
    • Control: adequate controls to protect against fraud or embezzlement; guarantee the accuracy adn security of data and information
    • Efficiency: maximum use of availible resource including people, time, flow of forms, minimum processing delays, etc.
    • Services: provide desirable and reliable service to those who need it. Also flexible and expandable
  • Other Issues
    • Usability Analysis
      • Ease of Learning: how long does it take to train someone?
      • Ease of Use: will it increase the productivity & efficiency of frequent users?
      • Satisfaction: is the interface and functionality pleasing to the users?

Technical Feasibility

  • A process of assessing the development organization's ability to construct a proposed system
  • Factors
    • Project Size
    • Project Structure
    • Development Group
    • User Group

Schedule Feasibility

  • The process of assessing the degree to which the potential time frame and completion dates for all major activities within a project meet organizational deadlines and constraints for affecting change.
  • Issues
    • Estimate at project initiation
    • Estimate at each cycle point

Economic Feasibility

  • A process of identifying the financial benefits and costs associated with a development project.
  • Issues
    • Tangible and intangible benefits
    • Tangible and intangible costs
    • One-time and recurring costs
    • Fixed recurring costs
      • Know ahead of time what the cost will be at each interval (insurance)
    • Variable recurring costs
      • Do not know ahead of time what the will be at each interval (utilities)
    • Present value analysis
    • Cost-benefit Analysis

Legal and Contractual Feasibility

  • The process of assessing potential legal and contractual ramifications due to the construction of the system.
    • Issues
      • Ownership of software
      • System licenses
      • Regulations

Political Feasibility

  • The process of evaluating how key stakeholders within the organization view the proposed system.
  • Issues
    • Distribution of information
    • Distribution of power
    • Support of stakeholders
      • Anyone who has a vested interest in the project
    • Primary stakeholder
      • Ex. Direct end-user and main financer of the project
    • Secondary
      • Ex. Critics
  • Management and End-users
    • Top management support?
    • End-users role in new system
    • Which end-users and managers might offer resistance?
    • How will the working environment change?

Wednesday 14 September 2005

Fact-Finding Methods Interviewing Questionnaires Record Review

Interviewing: The process of obtaining information by Means of Conversation Listening Observing Keeping conversation moving Keeping to the topic

Structured Uniform Questions Standard Administration / Evaluation Objective Results

Cost more to prepare High structure not pleasing High structure not always suitable Reduces spontaneity : the most important question just might be that question you don't ask

Unstructured Flexible Questions Pursue Spontaneous Ideas May find overlooked areas

Variance in administration may introduce biases Subject to extraneous info Lengthy Analysis

Do's and Don'ts Use self-validating questions a question to make sure we are all on the same wavelength answer is already known Use Controlling questions sparingly Don't use leading/ loaded questions Don't use self-answering questions Don't use 'parting shots'

Listening Skills Listen 'actively' Organize thoughts around central ideas reflect ideas & feelings for clarification TOLERATE SILENCE AVOID INTERRUPTING resist distractions be flexible

Body Language Hand movements Facial expressions eye contact posture proxemics

Respondent Behavior / Interviewer Action Guess at answers cross-check the answers tell what interviewer wants to hear watch for loaded/leading questions give irrelevant info focus- back to interview stops talking if notes are taken stop taking notes rushes interview reschedule wants NO change ask them to describe what is currently working resentment of interview explain your position refueses to give info ask to critque other's answers gripes focus -- do not contribute enthusiastic about new stuff focus -- do not jump on bandwagon

Questionaires: used to survey a large number of people Construction Testing Revision Data Collection Analysis Follow-Up

Questionaire Development Determine facts to be collected: Who can provide facts Select type Develop pool of questions: Build in redundancy Examine for problems Unnecessary Questions Wording of Question Ignorance to Question Leading Questions Inadequate Response Poor Ordering Pretest on small sample Analyze Edit Distribute

Observation: Occurs when analyst watchs or participates in an activity

Record Review: Examination of existing documentation( eg. Organization charts, policy manuals, procedures, input forms, printouts)

Monday 19 September 2005

Questionaire Development Determine facts to be collected: Who can provide facts Select type Strongly Agree/Strongly Disagree Interest Level Ranges Develop pool of questions: Build in redundancy Examine for problems Unnecessary Questions Wording of Question Ignorance to Question Leading Questions Inadequate Response Poor Ordering Pretest on small sample Analyze Edit Distribute

Observation: Occurs when analyst watchs or participates in an activity

Record Review: Examination of existing documentation Organization charts policy manuals procedures input forms printouts

Read up on the four symbols of modelling (data flow diagram) Process Data Store Agent Dataflow

Wednesday 21 September 2005

Data flows just move data

The process icon is the only place that work can be done

A data model looks at relationships amoung data

organized chunks of data are called entities

Two agents cannot directly flow data You can insert a process in between them or just dont show a link 'its none of your damn business'

A process can be seen as a program.

The whole diagram has no explicit sequence.

Context Level Level 0 Diagram System Level Diagram

You can explode, each process to get to more detail

Monday 26 September 2005

See the diagram in the docs folder for the class.

The four models: Logical Current - this is what it is Future - this what we want it to be (this is the one we will use) Physical Current - this is what it literally is Future - this is what we want it literally to be

Wednesday 28 September 2005

All class problems will have 2 levels of DFDs.

A 'p' on the end of the DFD number means that its primitive and it can't go deeper.

A grey hole is a process that doesn't have enough input to generate the output.

Make the data stores normal.

Monday 03 October 2005

We went over the Dentist System.

You need to check whether a agent is a sink, source or is a part of a process.

No if statements in a data flow. Use partial, or other adjective.

A dashed data flow line signifys a temporal event.

Exam Review (see review sheet): 21. Will be a DFD with flow errors 22. Will be the drawing of a DFD from a description.

Wednesday 05 October 2005

Exam, and it hurt.

Errr not too bad I got an 85.

Question 29 will be on the next test as well.

Question 3's answer is found on 158. Question 15's answer is found on 115.

29

  • Planning
  • Analysis
  • Design
  • Implementation
  • O

Monday 10 October 2005

Process Modeling - 'Data flow diagram'

  • Doing Something

Data Modeling - 'Entity Relationship Diagram'

  • relationship of organized 'groups' of data

groups of data is called entities and they have a number of attributes

  • field - (data item - data element) - attribute - domain - column
  • record - (occurance - instance) - tuple - row - object
  • file - data set - entity - table - ('class' special case)
  • db
    • relational
    • object-oriented
    • hiearchy
      • one parent, many children
    • network
      • many parents, one child

Primary ID

  • Unique Key
  • Combinaton Key
  • Concatenated Key

Wednesday 19 October 2005

compound attributes

Wednesday 26 October 2005

Monday 31 October 2005

Normal Forms

Wednesday 02 November 2005

Test on Chapter 7 next Wed.

Wednesday 16 November 2005

Went over userinterface design.

Wednesday 28 November 2005

Maintenance: any work done on any operational system, at any time for any reason

Relevance

  • 60-70% of DOD's software dollars are spent after testing and delivery
  • Companies spend 50% of software budgets on maintenance
  • Programmers spend 50-80% of time on maintenance
  • Maintenance often inefficient

Underemphasized?

  • Perceived as function for ... "misfits and outcasts"
  • not appreciated - necessary evil
  • programmers create program complexity:

Differences between Maintenance and Newer Systems Development

  • maintenance conforms to existing system contraints
  • maintenance normally involves shorter time frames
  • older systems typically more challenging

Typologies

  • Corrective Mainenance:
    • correct defects to keep the system operational
    • reactive process
    • 20% of maintenance task
  • Adaptive maintenance
    • performed as result to changing environment
    • add, delete, insert, extend, enhance
    • 20% of maintenance task
  • Perfective Maintenance
    • augment the quality, efficiency, reliability and documentation of the software
    • enhancements required by users
    • 60% of maintenance task

Forward-Engineering

Non-Engineered Systems

Re-Engineering

Reverse-Engineering

Transverse-Engineering

Renovation (Depends on:)

Critical Success Factors For Maintaining Software Productivity

Change Management

System Release Planning

Design Changes

Wednesday 30 November 2005

Presentations will be 12min or less

  • Prepare for 10min or less
    • Over 12min docks the grade of the project per min
  • Introduce the team
  • Summary of Opportunities
  • Show how your system works
    • addresses these 'areas of opportunity')
  • When can the system be delivered
  • How much will it cost?
    • (some details -HW,SW,Development)

Monday 05 December 2005

Exam review

  • Text easier to read
  • Combination check
  • Parts of a source document (one that contains code)
  • Different kinds of testing (check program that run abnormally)
  • Top down design = "water"? module design
  • Operations documentation
  • Access to operational environment
  • Guidelines for developing a training program
  • Conversion approaches
  • System analyst should do when evaluating a system
  • Effort IT dept puts into existing systems
  • Different kinds of maintenance
  • Advantages of rotating IT staff in system maintenance
  • Antiquated way of communication
  • Who is responsible for signing maintenance tasks
  • Measures of the quality of IT support
  • When has a system reached the end of its economically useful life
  • What marks the beginning of system operation
  • what marks the beginning of system operation?
  • and other such fun

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