Eight deadly defects insystems engineering and     how to fix them        Dr Joseph Kasser  Leverhulme Visiting Professor ...
Agenda1.   Selection of independent alternative solutions2.   The V Model3.   Lack of a standard process for planning a pr...
The selection of       independent alternative              solutions• The systems engineering process has  identified thr...
The “V” Model
Defects in the V                    Model• Lacks ‘prevention of defects’• Definition of successful test?• Design works fro...
The Project Cycle                      TestRequirement                 Design              Acceptance                crite...
Prevention of defective           requirements• Requirements Workshop  at UMUC and UniSA• FRED and Tiger Pro• Figure of Me...
Lack of a standard process  for planning a project Determination of objectives      Determination of Resources            ...
Lack of a standard process  for planning a project  Determination of objectives      Determination of Resources Identify a...
The Waterfall model• Waterfall approach does not cope well with  changing requirements.• Change the production process fro...
Assumption behind        Waterfall model       Contract awardWaterfall        Intermediate milestones                 (pro...
Real world of               changes      Contract award                 Desired                                  (moving t...
Assumptions behind  Cataract modelContract award    Desired (keep your                  eye on the balls)Cataracts Interme...
Unanswered and      unasked questions• Unanswered questions  – Can you tell if the project is in trouble?  – What percenta...
Project Priority profiles       (object-oriented        requirements)Why are we investing inthis system?                  ...
Project Risk profiles                  (object-oriented                   requirements)Risk: Is thisreasonable?           ...
Most successful IS of         the 20th century?• RAF Battle of Britain  Command, Control, &  Communications System   – No ...
Not solving        customers problems• “the systems engineer is primarily interested in making equipment  changes” [Goode ...
Complex orcomplicated?               19
The need to focus on   people as well as process• Literature  – Is full of advice as to    how to make projects    succeed...
The need to focus on    people as well as process• Systems engineering is a way of life  – (Hitchins 1998)  – Integration ...
Summary Selection of independent alternative solutions The V Model Lack of a standard process for planning a  project ...
Questions?
Upcoming SlideShare
Loading in …5
×

Eight deadly defects in systems engineering and how to fix them

1,574 views

Published on

Any organization desirous to adopt or improve systems engineering needs to be aware that research into the nature of systems engineering has identified a number of defects in the current systems engineering paradigm. This paper discusses eight of these defects and ways to fix or compensate for them.

Published in: Technology, Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
1,574
On SlideShare
0
From Embeds
0
Number of Embeds
18
Actions
Shares
0
Downloads
38
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Eight deadly defects in systems engineering and how to fix them

  1. 1. Eight deadly defects insystems engineering and how to fix them Dr Joseph Kasser Leverhulme Visiting Professor Cranfield University j.kasser@cranfield.ac.uk
  2. 2. Agenda1. Selection of independent alternative solutions2. The V Model3. Lack of a standard process for planning a project4. The Waterfall model5. Unanswered and unasked questions6. Lack of a metric for the goodness of Requirements7. Focus on technological solutions not solving customer’s problems8. The need to focus on people as well as process• Summary• Questions and discussion
  3. 3. The selection of independent alternative solutions• The systems engineering process has identified three alternative candidate solutions (A, B and C)• “C” gets the highest score• Which one is the optimal?• Possibly none of them• Possibly a combination of the best parts of all of them 3
  4. 4. The “V” Model
  5. 5. Defects in the V Model• Lacks ‘prevention of defects’• Definition of successful test?• Design works from requirements• T&E work from the need• T&E identify defects and plan to find them after they have been built into the system• Why not prevent the defects? * Kasser 1995 5
  6. 6. The Project Cycle TestRequirement Design Acceptance criteria (property of a requirement) 6
  7. 7. Prevention of defective requirements• Requirements Workshop at UMUC and UniSA• FRED and Tiger Pro• Figure of Merit for document• Produced attitude change in student’s perceptions• Produced better requirements 7
  8. 8. Lack of a standard process for planning a project Determination of objectives Determination of Resources Generate preliminary work plan (risks) Draft work plan version 1 8
  9. 9. Lack of a standard process for planning a project Determination of objectives Determination of Resources Identify and study lessons learned from previous projects Generate preliminary work plan (risks) Negotiate objectives and resources Draft work plan version 1 9
  10. 10. The Waterfall model• Waterfall approach does not cope well with changing requirements.• Change the production process from the waterfall approach to some type of rapid, spiral, or other methodology – Iterative waterfalls – Spiral focuses on Risk Management• Result – Some improvement • comparing Chaos 1995 with Chaos 2004 10
  11. 11. Assumption behind Waterfall model Contract awardWaterfall Intermediate milestones (product reviews) Vision of product Desired 11
  12. 12. Real world of changes Contract award Desired (moving target)Waterfall Intermediate milestones (product reviews) Vision of product 12
  13. 13. Assumptions behind Cataract modelContract award Desired (keep your eye on the balls)Cataracts Intermediate milestones (product reviews) Configuration Control (Stage Gates) Visions of product (converge) 13
  14. 14. Unanswered and unasked questions• Unanswered questions – Can you tell if the project is in trouble? – What percentage of the project is complete?• Unasked questions at SRR – Are requirements with the following properties really needed? • High cost, high risk • Low priority, high cost • Low priority, high risk – Is this projected risk profile industry standard? 14
  15. 15. Project Priority profiles (object-oriented requirements)Why are we investing inthis system? 15
  16. 16. Project Risk profiles (object-oriented requirements)Risk: Is thisreasonable? 16
  17. 17. Most successful IS of the 20th century?• RAF Battle of Britain Command, Control, & Communications System – No computers – Germany had better Radar Technology – RAF evolved and used an integrated system – Adequate technology• System?• System of Systems?• Complex System?• Network enabled system? 17
  18. 18. Not solving customers problems• “the systems engineer is primarily interested in making equipment changes” [Goode and Machol, 1959] page 130).• The problem the executive had was to secure at all times, live and accurate data concerning the exact conditions of the business. [Farnham, 1920] page 20)• [Beer, 1972] page 244) describes a conceptual system. – British War Room in the Battle of Britain – NASA’s control room at the Manned Space Flight Center in Houston, Texas. – bits and pieces of it existed at that time.• Beer proposed a control centre• Today’s technology allows for personal desktop portals accessing information via software agents in an integrated digital or network centric environment. 18
  19. 19. Complex orcomplicated? 19
  20. 20. The need to focus on people as well as process• Literature – Is full of advice as to how to make projects succeed – Has little if anything to say about the proliferating process standards 20
  21. 21. The need to focus on people as well as process• Systems engineering is a way of life – (Hitchins 1998) – Integration of • Schedules • Design, Testing and Integration • Systems of Systems divide?• Are we focusing on the right things? – The Standards do not provide metrics that can predict the failure of a project. • (K&W, 1998) 21
  22. 22. Summary Selection of independent alternative solutions The V Model Lack of a standard process for planning a project The Waterfall model Unanswered and unasked questions Lack of a metric for the goodness of Requirements Focus on technological solutions not solving customer’s problems The need to focus on people as well as process
  23. 23. Questions?

×