Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

System Development > Chapter 3 – Requirements Modeling > Flashcards

Chapter 3 – Requirements Modeling Flashcards

1
Q

System Analysis Activities

A 
Requirements modeling (fact finding)
• Output:
	- Electronic/printed information produced by the system
• Input:
	- Data entered into the system
		~ Manually
		~ Automated
• Processes:
	- Logical rules applied
		~ Transform the data into meaningful information
• Performance:
	- System characteristics:
		~ Speed
		~ Volume
		~ Capacity
		~ Availability
		~ Reliability
• Security:
	- Hardware, software and procedural controls
		~ Safeguards and protect the system and its data from internal or external threats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Modeling Tools and Techniques

A
  • CASE Tools
  • Functional Decomposition Diagram (FDD)
  • Data Flow Diagrams (DFD)
  • Unified Modeling Language (UM Language)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

CASE Tools

A
  • Offer powerful modeling features

* Systems analyst use modeling and fact-finding interactively

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Functional Decomposition Diagram (FDD)

A

Structure charts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Data Flow Diagrams (DFD)

A 
Shows how the system:
• Stores
• Processes
• Transforms
	-Data
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Unified Modeling Language (UM Language)

A

• Widely used method of visualizing and documenting software systems design
• Use case diagrams
- Actor
• Sequence diagrams

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

System requirement

A

• Characteristic or feature
- Must be included in an information system
~ To satisfy business requirements
~ Be acceptable to users

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Systems Requirements Checklist

A 
Five general categories:
• Outputs
• Inputs
• Processes
• Performance
• Controls
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Outputs

A
  • Website – Report online volume statistics every 4 hours

* Inventory system – Produce a daily report showing part number, description, quantity on hand, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Inputs

A
  • Manufacturing employees – Swipe their ID card into online data collection terminals (record labor costs, calculate production efficiency)
  • Department head – Enter overtime hours
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Processes

A
  • Student records system – Calculate GPA at the end of each semester
  • Payroll system – Update employee salaries, bonuses and benefits, and produce tax data
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Performance

A
  • System – Support 25 users online simultaneously

* Response time – Not exceed 4 seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Controls

A
  • System – Provide logon security (at operating system level & application level)
  • Employee record – Added, changed or deleted (only by a member of human resources department)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Future Growth, Costs and Benefits (*)

A
  • Scalability

* Total cost of ownership (TCO)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Scalability

A 
• System’s ability to:
	- Handle increased business volume
	- Transactions in the future
• Scalable system:
	- Offers a better return
		~ On the initial investment
• To evaluate scalability:
	- Requires information about projected future volume for all:
		~ Outputs
		~ Inputs
		~ Processes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Total Cost of Ownership (TCO)

A

• System developers:
- Identify
- Document
~ Indirect expenses (other than direct costs)
• That contributes to the total cost of ownership
• Especially important if:
- The development team is evaluating several alternatives
• Problem:
- Cost estimates tend to understate indirect costs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Direct costs

A 
• Spent on products
• Expenses used in:
	- The creation of the products
	- Examples:
		~ Costs of materials to produce the product
		~ Equipment, labour costs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Indirect costs

A 
• Do not spend on a product
• Expenses needed for:
	- Operating the company
• Examples:
	- Cleaning supplies
	- Office equipment
19
Q

Fact-Finding

A

• Fact-Finding Overview
- Identify the information needed
- Develop a fact-finding plan
• Who, What, Where, When, How, and Why?
- Difference between asking:
~ What is being done (Now) – Current System
~ What could or should be done (Future) – Proposed System

20
Q

Fact Finding Techniques

A
  • Interviews
  • Document Review
  • Observation
  • Questionnaire
  • Surveys
  • Research
  • Site Visits
21
Q

Interviews

A

• Seven steps

• Step 1: Determine the People to Interview
	- Formal structure
		~ From organization chart
	- Informal structure
		~ Based on interpersonal relationships

• Step 2: Establish Objectives for the Interview

- General areas to be discussed
- Lists the facts you want to gather

• Step 3: Develop Interview Questions
- Create standard list of interview questions helps keep you on track
- Avoid leading questions leads to only a single direction/answer
~ Example:
+ What advantages do you see in the proposed system?
- Avoid open-ended questions:
~ Anything can be an answer (no fixed/standard answer)
~ Example:
+ How is this task performed?
- Avoid close-ended questions there is a fixed/standard answer
~ Examples:
+ How many computers do you have in this department?
- Avoid range-of-response questions
~ Scaling answer
~ Example:
+ On a scale of 1 to 10, with 1 the lowest and 10 the highest, how effective was your training?

• Step 4: Prepare for the Interview
	- Careful preparation is essential
		~ Interview is an important meeting
	- Limit the interview time
		~ No more than 1 hour
	- Send a list of topics
	- Ask the interviewee to have samples available
• Step 5: Conduct the Interview
	- Develop a specific plan (for the meeting)
	- Begin:
		~ Introducing yourself
		~ Describe the project
		~ Explain the interview objectives
	- Engaged listening
	- Allow the person enough time to think about the question
	- After an interview:
		~ Summarize the session
		~ Seek a confirmation
• Step 6: Document the Interview
	- Note taking:
		~ Kept to a minimum
	- After conducting the interview:
		~ Record the information quickly
	- After the interview:
		~ Send memo to the interviewee expressing your appreciation
	- Note:
		~ Data
		~ Time
		~ Location
		~ Purpose of the interview
		~ Main points discussed
			\+ so the interviewee has a written summary and can offer additions or corrections.

• Step 7: Evaluate the Interview
- Identify any possible biases
- Example:
~ Give incomplete answers
~ Refrain from volunteering information
~ Strong opinions about the current or future system might distort the facts
~ Answers questions in an attempt to be helpful but do not have the necessary experience to provide accurate information

• Unsuccessful Interviews
- Some are not successful
~ No matter how well prepared you are for interviews

22
Q

Interview Summary

A
  • Determine the people (1)
  • Establish objectives (2)
  • Develop interview questions (3)
  • Prepare (4)
  • Conduct (5)
  • Document (6)
  • Evaluate (7)
23
Q

Other Fact-Finding Techniques

A
  • Document Review
  • Observation
  • Questionnaires and Surveys
  • Sampling
  • Research
  • Interviews versus Questionnaires
24
Q

Document Review

A

All paper & documents must be analyzed

25
Q

Observation

A 
o	Seeing the system in action
	Gives additional perspective
	Better understanding of the system procedures
o	Plan observations in advance
o	Hawthorne Effect
26
Q

Questionnaires and Surveys

A

o Most important rule of all:
 Make sure that the questions collect the right data
• In a form that can be used to further his/her fact-finding
 Fill-in-form

27
Q

Sampling

A

o List of 200 customers – representative sample of 20 customers
o Systematic sample
 Interview every 10th customer
o Stratified sample
 Geographical
 Choose 5 customers from each of 4 postal codes
o Random sample
 Choose any 20 customers
o Main objective:
 Ensure that it represents the overall population accurately

28
Q

Research

A 
• Includes:
		~ Internet
		~  IT magazines
		~ Books
	- To obtain:
		~ Background information
		~ Technical material
		~ News 
	- About industry trends and developments

• Site visit
- Going to a location or visiting

29
Q

Interviews versus Questionnaires

A 
• Interview:
	- More familiar
	- Personal
• Questionnaire:
	- Gives many people the opportunity to:
		~ Provide input
		~ Provide suggestions
• Brainstorming
	- Structured:
		~ Take turns to give ideas
	- Unstructured:
		~ Anyone can give ideas anytime
30
Q

Documentation

A 
• The Need for Recording the Facts
	- Record information
		~ As soon as it is obtained
	- Use the simplest recording method
	- Record your findings in such a way that:
		~ They can be understood by someone else
	- Organize documentation
		~ Related material can be located easily
• Software Tools
	- CASE Tools
	- Productivity Software
		~ Word processing
		~ Spreadsheets
		~ Database management
		~ Presentation graphics program
		~ Histogram
	- Graphics modeling software
	- Personal information managers
		~ Personal information manager (PIM)
		~ Handheld computers
		~ Personal digital assistants (PDAs)
	- Wireless communication devices
31
Q

Preview of Logical Modeling

A

• Systems developers:
- Have a clear understanding of business processes and system requirements
• Construct a logical model of the system

32
Q

Overview of Data and Process Modeling Tools

A

• Data Flow Diagrams (DFD)
- Uses various symbols
~ Shows how the system transforms input data into useful information

33
Q

Data Flow Diagrams (*)

A

• Shows:
- How data moves through an information system
~ Does not show program logic or processing steps
- WHAT the system does
~ Not HOW it does it

34
Q

Data Dictionary / Data Repository (*)

A 
• Central storehouse of information
	- About the system’s data
• Used by an analyst to:
	- Collect
	- Document
	- Organize
		~ Specific facts about the system
• Defines and describes:
	- All data elements
	- Meaningful combinations of data elements
• Data element / Data item / Field:
	- Smallest piece of data
		~ That has meaning
	- Combined into records
		~ Also called data structures
• Record:
	- Meaningful combination of related elements
		~ That is included in a data flow
		Or
		~ Retained in a data store
35
Q

Process Description Tools

A

• Process description:
- Documents the details of a function primitive
~ Represents a specific set of processing steps and business logic
• Can also be used in object-oriented development
• Modular design
• Combinations of 3 logical structures / control structures
- Serve as building blocks for the process
~ Sequence (1)
~ Selection (2)
~ Iteration-looping (3)
• Structured English()
• Decision Tables()
• Decision Trees

36
Q

Structured English(*)

A 
• Must conform to the following rules:
	- Use only the three blocks of:
		~ Sequence
		~ Selection
		~ Iteration
• Indentation:
	- For readability
• Use a limited vocabulary including:
	- Standard terms used in the data dictionary
	- Specific words that describe the processing rules
• Resembles pseudocode
• Primary purpose:
	- Describe the underlying business logic
37
Q

Decision Tables(*)

A

• Shows logical structure with:
- All possible combinations of conditions
- Resulting actions
• Important to consider every possible outcome:
- Ensure nothing is overlooked

38
Q

Decision Trees

A 
• Graphical representation of:
		~ Conditions
		~ Actions
		~ Rules
	- Found in a decision table
• An effective way
	- To describe a relatively simple process
39
Q

Logical vs Physical Models

A
  • Structured analysis tools
  • Physical model
  • Sequence of Models
  • Four-Model Approach
40
Q

Structured analysis tools

A

• Used to:
- Develop a logical model for a new information system
• Can also be used to:
- Develop physical models of an information system

41
Q

Physical model

A

Shows how the system’s requirements are implemented

42
Q

Sequence of Models

A

• System analysts:
- Create a physical model of the current system (1st step)
- Develop a logical model of the current system (2nd step)
- Tackling logical model of the new system (3rd step)
• Allows them to:
- Understand the current system better

43
Q

Four-Model Approach

A 
• Develop a:
	- Physical model of the current system
	- Logical model of the current system
	- Logical model of the new system
	- Physical model of the new system
• Disadvantage:
	- Added time
	- Added cost

System Development (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions