Systems and Lifecycles

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Systems and Lifecycles

• Chris Wallace

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7 Systems

• S1, S1 Context System
• S2 Intervention System
• S3 Realization System
• S4 Deployed System
• S5 Collaborating System
• S6 Sustainment System
• S7 Competing System
• P1 Initial Problem
• P2 Consequential Problem

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S1
P1
S3
S2
S7
S4
P2
S6
S1
S5
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P1 - Problems

• Hard and Soft
• Hard problems problem is simply identified,
  stated and agreed by all parties
• Soft problems - Problem identification is
  problematic, hard to state and seen differently
  by different parties
• wicked problems (Horst Rittel)
• Methods to address soft problems
• P1 is often lack of fitness of an existing
  system
• Recognition of multiple viewpoints - CORE
• Peter Checklands Soft Systems Methodology gtgt

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S1 - Context

• Bounding
• Bounded rationality ( Simon)
• We can never hope to understand the entire
  context
• We must limit our attention to things which
  matter most
• Satisficing not Optimising
• Is this just another cognitive limitation?
• Dynamic
• S1-gtS1-gtS1how the Context is expected to
  evolve

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System and Context

• System
• A recognisable whole which consists of a set of
  inter-dependent parts. More specifically
• A system is an assembly of components connected
  together in an organised way
• The components are affected by being in the
  system and the behaviour of the system is changed
  if they leave it
• This organised assembly of components does
  something
• This assembly as a whole has been identified by
  someone who is interested in it i.e. the agent,
  the client, or the problem owner
• From Carter, et al, Systems, Management and
  Change textbook for OU module T301
• The concept of a system is a thinking tool.
• To be useful system cant just mean stuff

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S3 the Realisation System

• Much of the attention of Systems Engineering is
  on S3
• Engineers build planes
• System Engineers build plane-making systems
• S3 is a Human Activity system a meat system
• People, roles, organisational structures,
  procedures, documents, training programs
• Emphasis on
• Knowledge management
• Information communication
• Decision making and tracking
• Re-use
• Of people, procedures, design and analysis tools,
  manufacturing processes
• Assemblage of often inflexible resources

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Smart Acquisition

• A whole-life approach through life costing -
  Through Life Management Plan (TLMP)
• Integrated Project Teams (IPT)
• More investment during early project phases
• Effective trade-offs between systems performance,
  through life costs and time
• Two process models
• CADMID for new equipment
• CADMIT for procurement

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CADMIDA Mandated Approach

• Concept
• URD User Requirements Document
• Initial Gate
• Assessment
• SRD Systems Requirements Document
• Main Gate
• Demonstration
• Manufacture
• In-service
• Disposal

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ISO 15288 A Contingent Approach

• Defines Multiple Processes in the systems
  lifecycle.
• Each life cycle Process can be invoked, as
  required, at any time throughout the life cycle
  and there is no definitive order in their use.
  Draft

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S3 (Realisation) ltgt S1 (Context)

• Knowledge acquisition
• Gathering of understanding of the context and the
  problem gtgt
• Description
• Of the context and problem
• Then of the proposed S2 in stages of reduction in
  solution space (set of possible S2s)
• Idea
• KPI (Key Performance indicators)
• Brief
• URD (User Requirements Document)
• SRD (Systems Requirements Documents)
• Architectural Design
• Detailed Design

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Trade-offs

• Nothing we design or make ever really works. We
  can always say what it ought to do, but that it
  never does. The aircraft falls out of the sky, or
  rams the earth full tilt and kills people. It has
  to be tended like a new-born babe. It drinks like
  a fish. Its life is measured in hours.
• David Pye , The Nature of design,1964

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Descriptions

• Multiple languages of description
• Text
• Requirements
• Diagrammatic
• 22 kinds in 12 papers in INCOSE conference
• Martin uses a form of ER model structure
• We also need to describe dynamics, interactions,
  interface
• SysML is a modification of UML (Unified Modelling
  Language) for SE gtgt
• UML has 13 kinds of model
• Most descriptions are of S2 (the form), not S1
  (the problem)
• Michael A. Jackson argues system engineering
  requires a greater focus on the problem and
  context we leap into the solution space too
  quickly gtgt

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S2 - The Intervention System

• The system being developed
• A400M, Beagle 2, NHS Information System
• But also
• The GCSE /A level examinations in schools
• Daylight saving
• The law no smoking in pubs and clubs
• Are these all systems?
• The Form designed to fit the Context

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S2 -gt S4 Deployed System

• Processes
• Manufacture
• Training
• Field and Customer Adaptation
• Installation
• Cases
• 3-day Car
• NPfIT (NHS national programme for IT)
• 2.3bn initial funding
• Risen to 6.2bn procurement costs
• Total implementation costs 12bn to 24bn
• Life-cycle costs 1.5 times Channel tunnel

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S1 S4

• We have to understand the context so well that
  when we implement our solution it fits perfectly.
• A Simple situation
• Context is bar magnet
• Form is the arrangement of iron filings
• Objective is perfect fit of the form when its
  placed in the context
• Two extremes
• Traditional approach trial and error
• Design approach model and predict solution
  fitness before build
• Requirements are a surrogate for S1

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S3 ltgt S1

• Fit is not enough
• Usually we want to change the context in some
  desirable direction
• Others are trying to compete with or destroy our
  system (S7)
• S1 and S4 change throughout the lifetime of S4
• We use models and theories to attempt to predict
  the behaviour of S4 in S1
• Models and theories to predict how the system
  will behave under different circumstances
• General systems theory
• Causal diagrams
• Systems thinking gtgt
• Analysis to predict all the possible ways in
  which the system can fail and counter them
• Genesis failure
• Failure analysis gtgt

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Genesis failure

• Investigators may have discovered what caused
  the Genesis spacecraft to crash into the Utah
  desert this September. Some crucial switches were
  installed backwards, because of an error in the
  instructions.The problem stems from the craft's
  design drawings, made by Lockheed Martin in 2001.
  They showed that some tiny cylindrical plungers,
  designed to detect the gravity of an incoming
  planet and deploy a parachute, were installed the
  wrong way. There were four such switches - two
  as a backup in case the first two failed. But all
  of them had been installed backwards. As a result
  the parachute didn't open, and the capsule
  plummeted to Earth.None of NASA's review
  processes picked up the mistake. "It would be
  very easy to mix this up," says Michael
  Ryschkewitsch, chair of NASA's mishap
  investigation board at the Goddard Space Flight
  Center in Greenbelt, Maryland. Investigators had
  to X-ray the crashed craft to confirm that the
  devices were the wrong way round.

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S5 Collaborating Systems

• Multiple existing systems into which the deployed
  system has to fit.
• If already existing, they must be part of S1 and
  thus need to be understood and described.
• Collaborating system vary in their degree of
  co-operation
• Regulatory authorities little co-operation
• Partners much co-operation

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S6 Sustainment System(s)

• Systems which need to be developed alongside S2
• Documentation
• Training
• Maintenance
• Spares
• Difference between Sustainment and Collaboration
  is a matter of degree or control

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P2 Consequential Problems

• Does the engineer have an ethical responsibility
  for the consequences of her systems?
• Are unanticipated consequences simply the result
  of poor analysis?
• Are consequential problems good for business?
• Every problem we solve
• Creates 10 problems more Piet Hein

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Poem The centipedeby Mrs Edmund Craster (d.
1874)

• A centipede was happy quite,
• Until a toad in fun
• Said Pray which leg moves after which ?
• This raised her doubts to such a pitch
• She fell exhausted in a ditch,
• Not knowing how to run.

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• While lying in this plight,
• A ray of sunshine caught her sight
• She dwelt upon its beauties long,
• Till breaking into happy song,
• Unthinking she began to run,
• And quite forgot the croakers fun.
• Agile development - Bedoll paper

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Workshop

• Apply the Martin Framework to the following
  situations
• a) S2 is the A400M
• b) S4 is a KLM-owned Boeing 747 PH-BLF
• c) P1 is Sadaam's Weapons of Mass Destruction
• d) S2 is the proposal to retain daylight saving
  all year.
• e) S2 is Martin's paper, 'the Seven Samurai'

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