Lecture 4 Conceptual System Design

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Lecture 4 Conceptual System Design
Introduction to Functional Allocation ISE 222
Spring 2005Notes Course Materials
www.engr.sjsu.edu/kcorkerKevin.Corker_at_sjsu.edu

• Kevin Corker
• San Jose State University
• 2/10/05

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Agenda

• Review System ID Scope and Bound Process
• Complete the IDEF and action based costing
• Preliminary Design Review Process
• Introduction to Human Factors
• Review Homework (with individuals and teams)

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Identification of Need

• Gap
• New Techniques
• New System Requirements added
• System Requirements Change Priority
• Political Views Shift
• Involve the customer unless the customer has
  changed as well

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System Definition MatrixNational Identity
Confirmation Process
Scope
Bound
Needs
Objt
Criteria
Params
Var
Constrnt
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National Identity Confirmation ProcessNeeds

• Ability to determine the identity of individuals
  in this country
• quickly
• at any place or time
• to assure accuracy of identity information
• to assure privacy and security of individuals
  identity

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National Identity Confirmation ProcessObjectives
Criteria
Parameters

• To institute a national identification process
• Portable and reliable
• To provide appropriate authorities with
  information
• Name
• Address
• Visa/citizenship status
• Criminal Information
• Health Information
• Contact and NOK (next of kin) Information
• Tracking???

• Able to be carried on or in person
• whgt,lt 4 oz
• Volume lt 2 cubic centimeters
• Able to be accessed by pedestrian, automotive, or
  desk based systems
• Able to link to national information sources
• Wireless access range
• Access queue management
• Bandwidth

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To provide appropriate authorities with
informationObjectives

• Easy access
• Time to access
• Encumbrance fro access
• Voluntary or not access process
• Validation of data

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National Identity Confirmation ProcessObjectives
Criteria

• To secure ID from tampering or duplication
• To secure ID from un authorized access
• To keep all information current

• Sealed no remote access
• Access limited
• Update Rate compatible with National Standards
• Update per week??

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Alternatives

• A1 Hand carried ID with federal specification
  and on board storage
• A2 Bio-referenced ID for identity with link to
  data store for other information
• A3 Implanted RF-ID with data on board and with
  link to data store for other information

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Secure
All Environ access
Lightweight
Accessible for mods
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Implanted
Hand Held
Bio-ID
Asynchronous Constant Update
Full Cross Index
Wireless Data Base
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Privacy
Public
1
Security
2
Accuracy
3
Convenience
Access Ease
1
Authorities
Info Density
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2
Info currency
3
Priority
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Functional Analysis and Allocation
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Action Reference Framework

• To (do something) to (something) somehow
• Action , object, modifier
• Used to describe a process
• Functional Decomposition is to develop a
  description of what the system must do not
  necessarily tied to how the system must do it.

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Functional Flow Block Diagram
Boolean Operator
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Hierarchic Structure for Decomposition

• Sub Functions operate on input/output consistent
  with the higher levels of the hierarchy
• Models the flow of data or objects in a system

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ICOM
Control
Activity
Inputs
Outputs
Mechanism
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Method of Analysis

• Shows roles of information and materials with
  respect to activity
• Each ICOM represents an activity or business step
  that can be broken down
• Inputs information/material used to produce
  activity output
• Controls Constraints on an activity
• Mechanisms That perform processing or provide
  energy to the activity (people or machines as
  mechanisms)
• Output The product of the activity

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Context Diagram
Control
Activity
Inputs
Outputs
A0 Purpose Viewpoint
Mechanism
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Target OOB
Procedures
Procedures
Sight Designate Target
orders
Expected Result
Select Prepare Ordinance
Ordinance Inventory
Guidance Equip
Deliver Ordinance
Access Damage
Captain
Automation
Gunner
Gunner
Automation
Captain
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Steps in Functional Decomposition

• Develop Context Diagram of Full System
• Decompose System to Sub-elements (ICOMS for all)
• Define Business Rule/Model
• AS-Is the descriptive scenario
• To-Be the future business or process model
• Cost Analysis
• Analysis of activities,
• Gather costs,
• Trace costs to activities,
• Establish output measures,
• Analyze costs

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Provision Aircraft Primary Secondary Input costs Output Measures
Propulsion Jet Fuel Fueltrck ops (150,000) (10,000) Passenger-revenue miles (80800)/1000
Fire control (1,000)
Life support Oxy, meds, safety equip Flight attend training (10,000) (2,000) Certification freq
Inspection (1,000) Certification freq
Safety Instructions Production/distribution (500) Certification freq
Lights, belts , etc ( Installation/maintenance (500) Certification freq
Quality of trip Food (d) Preparation (5,000) Meals produced/ meals consumed
Storage (5,000)
Heating/Cooling Galley (5,000)
Distribution (2,000)
Blankets/pillows (d) (100) Passenger requests

In-flight entertainment (d) (250) Hours of use
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Steps/Perspectives for System EngineeringAnalysis

• System Analysis
• Identification of the impacts and consequences of
  alternative approaches to system solution
• Identification of the quality, market,
  reliability, cost, effectiveness, benefits,
  longevity, aesthetics of alternative system
  solutions
• Iterative Refinement of Alternatives
• Sensitivity Analysis and Parameter Identification

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Supportability

• Inherent Characteristics of system design
  installation that enable efficient maintenance
  and support of the system
• Prime Elements
• Design Reliability Quality and Maintenance
• Maintenance Infrastructure
• Maintenance
• Training
• Supply chain support
• Equipment
• Packaging
• Faculties
• Technical Data

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Preliminary Design Review (due 2/17)

• Identify design alternatives (at least 2)
• for functional capability
• support reliability
• allow for maintainability
• Usability safety
• Support for service

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Human Factors Introduction
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Systems Engineering Approach to HCI
Features Automation
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Motor Behavior Theory for Guidance in Design and
Selection of Input Devices

• Purpose to match a physical output on the part of
  a user to a signal that is recognizable by a
  system.
• Bandwidth range of expression
• Dynamics speed of response
• Dimensionality physical and temporal relations
  that the input device can support
• Affordance appropriate and expected response
  in use and in feedback
• E.g. button click or highlight changes in
  isotonic devices
• Discrete entry devices and Continuous entry
  devices
• Physical limits
• Ergonomic consideration
• Environmental impacts vibration, clothing
  restrictions, noise and etc.
• Physical Measurement, information theory and
  neuromotor accuracy

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Human Performance Models

• What are they?
• Expressions of relationships that either describe
  (descriptive) or predict (normative) human
  behavior across a range of environments or
  contexts
• Specifics
• Perceptual Models, Information Processing Models,
  Motor Behavior Models, Decision Models, Framework
  Models, Unified Models.

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INFORMATION MEASUREMENT

• Information property of messages and data or
  other evidence that reduces ones uncertainty
  about the true state of the world.
• Let x represent a hypothesis about the state of
  the world
• Let y represent the observation that has a
  relation to x
• I(xy) is the relation of the observation to the
  state of the world
• I(xy) should be a function of the prior
  probability of x before y is observed and the
  posterior probability of x after y was observed
  F p(x), p(xy)

log2 P(xy)/p(x)
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Information Qualification
Loss
Input
Output
Noise
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Information Qualification
What Effect does redundancy have on total
information transmission?
H
Loss
H(x)
H(y)
T(x,y)
Input
Output
Noise
C (bits/sec) bandwidth log2 (signal/noise1)
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H(x)
H(xy)
H(yx)
H(y)
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Hicks Law
Reaction Time
RT a b H(x) where H(x) log2(n)
.8 sec
.6 sec
.4 sec
.2 sec
1 2 3
4 5 6 7
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Bits 1 2
2.58 3
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Fitts LawMovement Time ab(Id) Id log2
2amplitude/(tolerance)
Movement time
.8
.6
.4
.2
Id 1 2 3 4
5 6 7