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EMIS 8390. Systems Engineering Tool—applying tools to engineering systems. Decomposition: Architecture & Trade Studies. UPDATED 9/20/04. Mark E. Sampson. Architectural Frameworks… …a means of representing, capturing, communicating system architectures from a variety of perspectives…
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EMIS 8390 Systems Engineering Tool—applying tools to engineering systems Decomposition: Architecture & Trade Studies UPDATED 9/20/04 Mark E. Sampson
Architectural Frameworks… • …a means of representing, capturing, communicating system architectures from a variety of perspectives… • 100’s of frameworks out there… • Aimed at different problem domains • Business/IS systems…Zachman, SEMS, EPIC,… • Tools help capture & support these frameworks…CaseWise, Synthesis,… • Usually can’t buy them without consulting • Business consultants each have their own extensions/tools [zifa.com]
Architectural Frameworks…continued • IDEF0-9…based on SADT • IDEF0—functional modeling… • IDEF1—information modeling… • IDEF1x—activity modeling… • IDEF2—system dynamics • IDEF3—process & states • IDEF4—object modeling • … • IDEF9—user interface • … • IDEF14—network modeling • Tools help capture & support these frameworks…KBSI, Popkin SA, ProSim,… [idef.com]
TCT Kill Chain Engaged by a Joint Battle Force J-STARS w ATR U-2 UAV TADIL NET DCGS XXX ARMY Tactical Operations Center CAOC XX XX BCC USMC TAOC XX AIR DEFENSE TOC AEGIS • Architectural Frameworks…continued • DoDAF…next generation C4ISR • Operational views • OV1-operational concepts • … • OV5-activities • … • OV9-logical Data • System views • SV1-interfaces • … • SV12-events • Tools help capture & support these frameworks…Popkin SA, Statemate, P-Tech… • Most used is Powerpoint, Excel,…
Architecture: Synthesis… • Translates functions into physical architecture by grouping functions into logical/physical elements • Elements include: hardware, software, material, data, facilities, people, services, and/or processes • Alternatives are evaluated against the requirements to identify best approach • Continue to develop architecture until you can verify that requirements have been met • …produces WBS, spec’s, & CI’s Motor Battery Drive Processor [SE Handbook 10] [DOE 2003]
Architecture: Synthesis… • You “just” have to choose an architecture that: • Satisfies the requirements • Implements the functions • Within budget, time, knowledge, resources,… • Built with available technology & availability risk • Is extensible to accommodate growth & new technologies • Allows you to go the next level of detail • Is robust enough to minimize back-tracking • …you may be starting from scratch or from existing art • …in a changing environment [SE Handbook 10]
Systems Synthesis FunctionalAnalysis Systems Analysis Problem Definition Decomposition VerificationValidation Develop Alternatives Develop Alternatives Develop Architecture Develop Architecture Choose Alternative Choose Alternative • Architecture: Synthesis… • Develop alternatives use the tools previously described—brainstorming, morphing, surveys, literature search, Pugh, TRIZ,… • Develop architectures from those alternativesuse diagrams/models of appropriate types (at appropriate level) • Choose & dive to the next levelapply criteria, decision trees, weighting, utility curves… • Repeat until components arerealizable, verifiable… [SE Handbook 10]
Modeling Methodology: Schematic Block Diagrams • …capture & communicate potential product architecture, what makes it up, & their interactions • Shows internal & external interfaces without pushing a particular design • Encourages looking “outside the box” • In our dental hygiene case, • shows the preliminary • product partitioning Partitioning [Armstrong 1993]
Modeling Methodology: Behavior Diagrams • …combine data flow and functional flow • More thorough analysis of actions & what is being acted on in the same diagram. • Support function to system allocations • …tools like CORE, Cradle-SEE,…use thesetypes of diagrams [Armstrong 1993]
Modeling Methodology: State Diagrams • …analysis of system states or modes • Identify lock conflicts—on, standby,… • Identify transition problems during design • Presentation/Demo by I-logix • In our dental hygiene case, shows the system needs to be made ready before it can be used [Armstrong 1993]
Modeling Methodology: Object Oriented Analysis • …identify what the system will have to deal with as objects • Similar to mission profiles, schematic block diagrams,… • UML/SysML… • Presentation by Sandy Friedenthal (LMCO/SySML Partners) • In our dental hygiene case, shows objects of our dental monitoring system [Armstrong 1993]
Modeling Methodology: Data Flow • …like functional flow, except emphasis on how information flows among system elements. • Helps identify data input/outputconflicts • Data dictionaries • In our dental hygiene case, shows a decomposition of monitoring brushing after meals [Armstrong 1993]
Modeling Methodology: others… • Entity-Relationship Diagrams • Math models (Excel, Matlab,…) • Statistical Models—DFSS,…(SAS, MiniTab,…) • Performance models—Queuing, Monte Carlo, etc. (Crystal Ball, SES Workbench,…) • Environmental Models— • Physical Models—Hydraulics, Electrical,…(Easy5, CAERose, Matlab:Simulink…) [Armstrong 1993]