HCI

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HCI
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Human Factors in Software Engineering (HCI
- Human Computer Interactions Alias MMI,
Automation Boundary
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HCI Requirements HCI Specifications Stand
ards MIL-H-46855B AFSC-DH 1-3 MIL-STD-1472 MIL
-HDBK-759A Factors Noise, Lighting,
Temperature, Humidity, Air Flow Vibration,
G-Forces, Motion, Reduced Oxygen, Air Pressure
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Screen Navigation
While we have defined use cases, objects and
their relationships through object diagrams and
sequence diagram to define interactions between
objects. We are now ready to define and design
our screens. Perhaps we need a method of
specification of screen navigation.
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Objectives of GOOD HCI Design Reduce
Errors Increase Safety Improve
Reliability Improve Maintainability Reduce
Training Requirements Reduce Personnel
Requirements Improve Working Environment Reduce
Fatigue and Stress Increase Comfort Reduce
Boredom Increase User Acceptance Reduce loss of
time Increase Efficiency Improve Inf Sys
Performance
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Five Step Process Step 1 System Function
Allocation Which processes require HCI - Use
Cases Step 2 Operational Timelines Step-by-Step
description of human interaction with
computer Step 3 Operational Task
Analysis Analyzing tasks (Start times, Step
Names, Description, Cues for starting) Informati
on needed by user, evaluations and decisions,
actions required Duration and frequency,
concurrent tasks, communication and
coordination)
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Five Step Process Step 4 HCI Design System
Failures (error messages, logging), Help
Packages, Response Times Characteristics,
Guidelines and Standards Step 5 HCI
Testing Tests results of operational timeline
and HCI design
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Five Step Process Step 1 System Function
Allocation Which processes require HCI - Use
Cases Using the Use Case Diagrams, define
the 0..n cases which need HCI designs. Some may
not require HCI designs, only screen
designs Some may need more than one HCI designs
Use Cases Custodials
Operator Functions
Allocate System Functions
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Step 2 Operational Timelines Step-by-Step
description of human interaction with
computer Good Technique for documenting is the
sequence diagram with interacting screens
Operator Functions
Operational Timelines
Define Operational Timelines
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Step 2 Operational Timelines
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Step 2 Operational Timelines
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Step 3 Operational Task Analysis Analyzing
tasks (Start times, (under what conditions do
you start) Step Names, Description,
(narrative of task - user guide) Cues for
starting, Information needed by user, (data
operator needs) evaluations and decisions,
(what decisions need to be made by the
user) failure responses help available
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Step 3 Operational Task Analysis actions
required (what is the action, how often does
it have to be done- frequency, how long does
it take - duration , feedback given to user ,
body movements required by this action,
physical workspace required , location of
workplace, additional equipment needed,
experience required, concurrent tasks if
any, staffing description or limitations,
communication and coordination required)
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Step 4 HCI Design System Failures (error
messages, logging), Help Packages, Response
Times Characteristics, Guidelines and
Standards - MTBF
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Step 5 HCI Testing Tests results of
operational timeline and HCI design Does it
work Does it work correctly Is if efficient