Analysis Procedures

1
Analysis Procedures

• Mission Analysis Function Determination
• Function Allocation
• Task Description / Identification
• Task Analysis

2
Mission Analysis (System Requirements Analysis)

• What is the system supposed to accomplish?
• The analyst/designer needs to know -
• Specific Goals
• Required Outputs
• Required Inputs
• System Capacities and Performance Requirements
• Operating Environmental Factors
• Constraints on System Operation

3
Mission Analysis Tools

• Mission Profile Graphic Description
  (Example - Flight Profile)
• Mission Scenario Verbal Description -
  Summarizes typical assumptions, environments,
  operations.
• Mission Segment Time period of coherent
  activities with definite beginning and
  ending points.

4
Importance of Function Task Analyses

• Evaluate Human Factors Implications
• Design Requirements and Constraints
• Workload Implications
• Notes
• 1. Decompose to level where functions to be
  performed
• by system can be identified.
• 2. Be careful that proposed design solution
  does not
• appear to be a function description.

5
Determination of Functions

• Identify and Describe Functions - by
• Determining Function Inputs and Outputs
• Establishing Functional Performance
  Criteria
• Preparing Functional Flow Diagrams
• Function Examples
• To Detect
• To Repair
• To Analyze
• Functions - Can be
• Instantaneous (Start Engine)
• Prolonged ( Monitor Radar Screen)
• Complex (Analyze Equipment Malfunction)

6
Function Performance Criteria

• Yardstick used to measure/predict whether or not
  thesystem/function meets the performance
  requirements.
• Criteria can range from gross to finely
  detailed.
• Functional Performance Criteria must be stated
  in terms ofthose test results that must be
  satisfied in order for thesystem/function to
  meet the performance requirements.
• Provides the basis for preparing the Functional
  Flow Diagram.

7
Functional Flow Diagram

• Determine the functions that have already been
  allocated.
• Describe the various different ways that each
  unallocatedfunction might be accomplished.
• Establish the weighting criteria for comparing
  the alternatives.
• Compare each of the alternative against one
  another.
• Select the most cost-effective design.

8
Task Description / Identification

• Examine each selected design alternative.
• List in sequence all the actions that must be
  performed to accomplish thefunctional element.
• Categorize actions in terms of whether they
  areoperator or maintainer activities and by
  thehardware/software subsystems to which they
  belong.
• Describe each action in terms of a behavioral
  verb (see next slide).
• Break tasks down into subordinate tasks by
  specifying inputs and outputsfor each
  task/subtask.

9
Behavioral Verbs

• Action Example - to turn on, to monitor, to
  disassemble
• Equipment Acted Upon Example - switch, motor,
  display
• Consequence of Action Example - voltage display
  stabilized
• Stimulus that Initiates the Action Example -
  pilots command
• Feedback Information Resulting form Task
  Performance Example - aircraft heading 320
  degrees
• Criterion of task accomplishment Example -
  vehicle stopped/parked with 3 feet of marker

10
Task Analysis

• Design Questions
• Manning Questions
• Training Questions
• Test and Evaluation Questions

11
Design Questions

• What tasks need to be performed?
• How critical is each task?
• In what sequence must the tasks be performed?
• What control activations are required? etc,
  etc, etc, etc

12
Manning Questions

• How many people are required to perform the
  task?
• What skill levels are required?

13
Training Questions

• On what behavioral dimensions are the tasks
  performed?
• How difficult or complex is each task?
• What information is required to perform the
  task?etc, etc, etc, etc

14
Test and Evaluation Questions

• What are the performance criteria for the task
  or job?