Problem Areas with the Project

Class Descriptions were non existentUse case descriptions were terse or non

existentVerification methods were wrongEqual effort within teams

exam

ple

team

Intro 6% 1

Problem definition 12% 1

Organization 12% 1

System Definition 12% 1

Team Recommendation 6% 1

Prototypes 10%

Requirements table 18%Missing requirments? Assigned properly in table? 1

Domain Model 12% Missing classes? 1

Class descriptions 0% 0

Use cases 12%All use case identified. All alternatives identified 0.8

Use case Descriptions 12%Summaries for all use cases. 0.2

110%

Due date next Monday 12:00 Noon

Late -10% < 1 day 0

Very late -20% < 1 week 0

More than one file -5%88%

GradingGrading ExampleExample

Possible # of pointsPossible # of points

ChangeChangeWas 11%Was 11%

Penalty pointsPenalty points

Grades

88%88%104%104%88%88%92%92%86%86%95%95%0% - not started0% - not started75% - late75% - late

Average was 89.7 ( not counting the 0%)Average was 89.7 ( not counting the 0%)

Class Descriptions

Class Descriptions should introduce the reader to the object class It should be a paragraph It should denote

If it is a hardware, software, person, parameter … etcif it is a commercial productIF it is temporary, permanentPart of another class (aggregation composition)Anything else that you know about the class/ object

Use Case Descriptions

Use case descriptions should describe what the use case is doing and who is doing it.

It should:Indicate the goal of the Use Case. e.g. Indicate the scope and

duration of the use case.

This use case creates a valid order based on customer provided information. It is executed whenever the customer indicates a desire to finalize the order.

Since the information is private, this session is done in a secure mode. The entire process of entering an order is temporary and is aborted if the customer does not respond within a proper time frame.

All the order and customer information derived from this use case is stored in a secure server.

The process ends whenever all the information is collected and the customer indicates finished, the customer cancels the order, or the process times out from lack of activity.

Requirements Verification Methods

Most requirements should be tested. Test : The system is run in a particular sequence to show the

successful implementation of the requirement. The test must match the documented expected test results.

Demonstrate : While similar to test the requirement is shown to be correct. The result must be obvious. ( visible, audible… ) It must be difficult to attach a test result.

Inspect : Static characteristic shown to the customer. Analyze : Some type of analysis is performed and documented.

This could be a spreadsheet, simulation… the documentation must be captured in a formal paper.

Equal Effort Among Members Within Teams

Next TimeI will ask each member of a team to rate the other members

within the teamThis will affect the team member’s individual grades.

Homework : Due November 3rd

•Divide up your project classes among team members. Create class Divide up your project classes among team members. Create class descriptions. descriptions. •Divide up your project use cases among team members. Create / re-do Divide up your project use cases among team members. Create / re-do use case descriptions.use case descriptions.•Divide up requirements among team membersDivide up requirements among team members

•Send them to me ( subject: Project updates) Send them to me ( subject: Project updates) •Add them to your project (don’t send them to me)Add them to your project (don’t send them to me)

No class on October 27, 2003No class on October 27, 2003

Trade Study Purpose

Purpose : Trade study is used to objectively choose between multiple acceptable candidate solutions

Halloween PartyHalloween Party

Trade Study Description

select the best solution to meet an identified problem within defined constraints

Defines a structured analytic framework for evaluating a set of alternative concepts, designs, or components

Conducted concurrently with other requirements development and design activities

Range from an informal comparison of alternatives to major efforts using sophisticated computer tools for simulation and cost estimation.

?

WhatWhat Costume should I wear? Costume should I wear?

WhoWho should I go with? should I go with?

Trade Study Process

•Define ObjectivesDefine Objectives•Identify CandidatesIdentify Candidates•Establish Evaluation CriteriaEstablish Evaluation Criteria•Conduct analysisConduct analysis•Document ResultsDocument Results•Review Review

StakeholdersStakeholders can be: can be:

•Other business Other business disciplinesdisciplines

•CustomerCustomer

•CorporateCorporate

•YourselfYourself

•Etc.Etc.

Define Objective for Analysis

Define the objective and purpose of the analysis

Determine scope of trade studyDetermine level of supporting

analyses

Determine amount of review and approvals needed

Determine level of documentation

Obtain approval with stakeholders of the objective and ensure that there is agreement on the purpose and scope of the analysis

Define Objective for Analysis - Example

Objective:

Decide where best to eat lunch on a typical workday.

Purpose:

Get the best value for lunch

Scope:

Where, how, what, how much, with whom

Be sure to get approval of the purpose and scope of the objective from stakeholders.

Be sure to get approval of the purpose and scope of the objective from stakeholders.

Establish Evaluation Criteria and Weights

Establish an evaluation criteria and weighting for considering system design alternatives that includes, as a minimum, cost drivers, total ownership and life cycle cost, complexity, technical limitations, environmental impact, system expansion, growth, and risk.

Establish an evaluation criteria and weighting that is a tailored version of the standard criteria and weighting

Review the evaluation criteria to ensure that they are consistent with the range of alternatives.

Obtain agreement of decision maker on evaluation criteria and weights

Obtain agreement of decision maker on evaluation criteria and weights

WeightingCriteria Grade Weighting

Cost 1 – Very Low Cost Impact 2 – Low Cost Impact 3 – Medium Cost Impact 4 – High Cost Impact 5 – Very High Cost Impact

.25

Schedule 1 – Very Low Schedule Impact 2 – Low Schedule Impact 3 – Medium Schedule Impact 4 – High Schedule Impact 5 – Very High Schedule Impact

.25

Technical Performance 1 – Very Low Performance Impact 2 – Low Performance Impact 3 – Medium Performance Impact 4 – High Performance Impact 5 – Very High Performance Cost Impact

.25

Risk 1 – Very Low Risk 2 – Low Risk 3 – Medium Risk 4 – High Risk 5 – Very High Risk

.25

Tailor criteria and weighting as appropriate. Ensure weighting is normalized, and grading uses the

same scale (good=low) and range across criteria.

Tailor criteria and weighting as appropriate. Ensure weighting is normalized, and grading uses the

same scale (good=low) and range across criteria.

Establish Evaluation Criteria and Weights - Example

Cost 0.3

Time Required 0.3

Nutritional Value 0.3

Convenience 0.1

Most Trade Studies will have items related to Cost, Schedule, and Performance and Risk as part of their

evaluation criteria. Refer to SYSENG-100 Appendix E

Most Trade Studies will have items related to Cost, Schedule, and Performance and Risk as part of their

evaluation criteria. Refer to SYSENG-100 Appendix E

criteria

weights

Establish Evaluation Criteria and Weights - Example

Grades for

“Time Required”

0 to 15 minutes Very low impact (1)

15 to 30 minutes Low impact (2)

30 to 45 minutes Medium impact (3)

45 to 60 minutes High impact (4)

Over 60 minutes Very high impact (5)

Identify Candidate Alternatives

Generate alternative candidate solutions.

Reject unfeasible alternativesDocument rejected

candidates Feedback loop

Option 1Option 1

Option 2Option 2

Option nOption n

..

..

..

Option 3Option 3

Fast Food(e.g. McDonald's)

Full Service Restaurant(e.g. Foster's)

Company Cafeteria

Brown Bag

Identify Candidate Alternatives - Example

alternatives

For larger trade studies, it is a good idea to have a formal review of alternatives and criteria before proceeding with the analysis.

For larger trade studies, it is a good idea to have a formal review of alternatives and criteria before proceeding with the analysis.

Conduct Analysis of Alternatives

Develop timelines scenarios for system operation and user interaction for each system design alternative.

Allocate key requirements to the hardware and software components for each of the design alternative as a part of the analysis.

Analyze all candidate alternatives that have been identified. Analyze the alternatives using a structured decision making

technique that is appropriate for the analysis. Use the evaluation criteria and weighting to select the

recommended alternative (see example). Determine the alternative representing the “Best Value” for

projects that have a CAIV requirement. Evaluate the failure conditions associated with each of the

alternatives. Perform a sensitivity analysis to determine if any factors

inordinately dominate the selection outcome

Conduct Analysis of Alternatives - Example 1

eat

drive get eat drive

get eat

drive order wait eat pay drive

Full Service Restaurant

Fast Food

Company Cafeteria

Brown Bag

Example:

Timeline Analysis

Use analysis techniques such as timeline analysis, CAIV, analysis of possible

failure conditions, etc.

Use analysis techniques such as timeline analysis, CAIV, analysis of possible

failure conditions, etc.

Conduct Analysis of Alternatives - Example 2

Another Example:

Data Gathering

McDonald’s Web Site

Conduct Analysis of Alternatives - Example 3

Apply weights to grades

to find optimum alternative

Weight Fa

st

Fo

od

Fu

ll S

vc

Re

st

Ca

fete

ria

Bro

wn

Ba

g

Cost 0.3 2 4 3 1Time 0.3 3 4 2 1Nutrition 0.3 4 2 2 1Convenience 0.1 3 3 1 3

Score 3.0 3.3 2.2 1.2

Multiply weighttimes grade,

and sum acrossall criteria, i.e.

.3(1)+.3(1)+.3(1)+.1(3)=1.2

Document Analysis Results

The report contains the following:

Document the rationale for the analysis decisions.

Document the decision making technique used for the analysis and the rationale for its selection.

Document the rationale for the selection of the evaluation criteria and weighting for the analysis.

Document alternatives considered and the rationale for not selecting them as the recommended alternative.

It is recommend to produce the document incrementally in parallel with the process

It is recommend to produce the document incrementally in parallel with the process

Document Analysis Results – Style-guide

IntroductionIntroduce the subject of your analysis. Who are the users / stakeholders…

Requirements, Constraints, and AssumptionsWhat are the Big requirements and constraints. If you are not sure about something or can’t prove something list your assumptions.

Trade Study ObjectiveWhat are you trying to accomplish by doing this trade study

Definition of AlternativesTalk about the alternatives. Provide a narrative about each one of them with separate headings. Talk about the features of each.

Evaluation Criteria, Grading, Weighting and ScoringList and description of evaluation criteria. Create a table of grading, weighting and scoring. This is where the spreadsheet goes.

Conclusions and RecommendationsDescribe the results and pay particular attention to any conclusions that aren’t obvious

Document Analysis Results - Example

TRADE STUDY REPORT STYLEGUIDE

September 30, 1999

Weight Fas

t Fo

od

Fu

ll S

vc R

est

Caf

eter

ia

Bro

wn

Bag

Cost 0.3 2 4 3 1Time 0.3 2 4 2 1Nutrition 0.3 3 2 2 1Convenience 0.1 3 3 1 3

Score 2.4 3.3 2.2 1.2

eat

drive get eat drive

get eat

drive order wait eat pay drive

Conventional Restaurant

Fast Food

Company Cafeteria

Brown BagTrade Study Trade Study

ReportReport

Style-guideStyle-guide

Review/Approve Analysis Report

Review the assumptions to ensure that they are reasonable and valid for the alternatives being considered.

Review the selected alternative to ensure it is the best solution based on the evaluation criteria and weighting.

Review the candidate alternatives to ensure that the appropriate alternatives have been analyzed. If all appropriate alternatives have not been analyzed, then the analysis of alternatives needs to be continued

Trade Studies are usually conducted to help understand competing solutions and to select the most optimal solution. Trade Studies are usually conducted for items significantly impacting:

• Cost• Schedule• High Risk Items• Performance Objectives• Architectural Design

When to Conduct a Trade Study

Example Example SpreadsheetSpreadsheet

Grade score Grade scoreweight

ConfigurationSize of remote equipment

1 - very small2 - small3 -Medium4 - large5 -very large

3 0.07 3 0.07

2% 0.2

Weight of remote equipment

1 - very small2 - small3 -Medium4 - large5 -very large

2 0.04 4 0.09

2% 0.2

Power consumption of remote equipment

1 - >20 watts2 - >40 watts3 - >60 watts4 - >80 watts5 - >100 watts

4 0.13 4 0.13

3% 0.3

RMAReliability (MTBF) 1 - 10 year

2 - 8 years3 - 6 years4 - 4 years5 - 2 years

5 0.44 3 0.26

9% 0.8

Repair-ability (MTBR) 1 - 5 min2 - 10 min3 - 15 min4 - 20 min5 - 25 min

5 0.49 2 0.20

10% 0.9

Data Transfer{Technical Multi-path performance 1 - >40 Mbps 2 0.22 5 0.55

11% 1

Performance} Data Throughput 2- < 40 Mbps3- < 30 Mbps4- < 20 Mbps5- < 10 Mbps1 - >4 Mbps 1 0.11 5 0.55 11% 12- < 4 Mbps3- < 3 Mbps4- < 2 Mbps5- < 1 Mbps1-> 40 miles 1 0.11 4 0.44 11% 12-< 40 miles3-< 30 miles4-< 20 miles5 -< 10 miles

1 > 4Mbp 1 0.11 5 0.55 11% 12 < 4Mbp3 < 3Mbp4 < 2Mbp5 < 1Mbp1 – Very Low {<10$K} Impact 2 0.15 4 0.31 8% 0.72 – Low {<15$K} Impact3 – Medium {<30$K} Impact4 – High {<35$K} Impact5 – Very High {>35$K} Impact1 – Very Low {<100$K} Impact 3 0.16 1 0.05 5% 0.52 – Low {<150$K} Impact3 – Medium {<300$K} Impact4 – High {<350$K} Impact5 – Very High {>350$K} Impact1 – Very Low (March 03) Impact 3 0.33 1 0.11

11% 1

2 – Low (April 03) Impact3 – Medium (June 03)Impact4 – High (July 03) Impact5 – Very High (August 03) Impact1 – Very good maturity 5 0.27 1 0.05 5% 0.52 – good maturity3 – Medium maturity4 – High immaturity

{Risk} Maturity

Recurring cost

This cost is the cost of procurement of multiple units.

Development cost

Cost to develop the software and hardware environment to operate the unit.

802.11g VRC-99

{Schedule} Will the equipment be ready for deployment in April 03, August 03

OTH throughput

Reliable single vehicle Throughput

Distance of reliable operation