1 Simulation Conceptual Modeling Study Group Welcome to the Spring 06 Simulation Interoperability Workshop Meeting

2 Agenda Welcome and Introduction The SCM SG as I see it SCM SG Final Report SCM Standing Study Group Terms of Reference

3 History of SCM SG Meetings –Kickoff meeting during Spring 03 SIW –Follow-up Meetings during Euro and Fall 03, Spring and Fall 04, Spring and Fall 05 SIWs (121 Attendees) Progress –IAW TOR, established SISO reflector (now Discussion Group) with 79 subscribers –IAW TOR, issued data call on SCM SG reflector for empirical evidence on simulation conceptual modeling –Article in SISO Simulation Technology Magazine –Initial Draft of SCM Vision Statement –3rd Compilation of SCM Bibliography

4 Rationale The Simulation Conceptual Modeling Study Group has been formed to conduct preliminary investigation on the best practices of simulation conceptual modeling and to establish recommendations for pursuit of the topic within the scope of the SISO, if appropriate.

5 Community Description M&S Community Potentially Benefiting from SCM SG: –M&S sponsors/users –M&S requirement managers –M&S simulation designers –M&S software developers –M&S VV&A agents –Base Object Model Product Development Group –VV&A FEDEP Overlay Product Development Group (A large and diverse group)

6 Community Need A set of “Best Practices” does not exist for Conceptual Modeling M&S community fragmented on use of terminology Novice M&S designers, and developers left to develop ad hoc solutions for the transformation of sponsor/user requirements into simulation designs and software code M&S V&V Agents left with numerous difficulties in establishing credibility of finished products

7 Simulation Development Elements Model Real SystemComputer Modeling Simulation “A Bridge”

8 Conceptual Model Synthesized combination of simplified and abstracted parts of real world It represents an idealized approximation of the original complex real world system within the scope of the simulation An transformation process underlies simulation development –The real world is too complex to be understood much less modeled by humans –Most practical approach is to abstract key elements forming reasonable approximation of real world The simulationist responsible for ensuring the approximation is adequate for the intended purpose

9 Role of Conceptual Model A simulation developers method of translating modeling requirements into a detailed design framework- Pace Result of the “Art of Modeling” or the process of analysis, abstraction, simplification, and synthesis within a simulation development project A role of the CM is to document all requirements of the system and subsequent requirements and analysis of the models/federations. This allows for the systems engineering to flow into the simulation development.

10 Precepts of Conceptual Modeling A conceptual model should be malleable and adopt a coherent form located within one model appropriate for each particular simulation development phase Highly unstructured, informal models are sufficient during early simulation definition Structured and enhanced formal models appropriate during simulation development

Approach Publications Regulations Structured, Synthesized Information Domain Experts Legacy Systems Domain Analysis Problem Domain

12 The Informal Model Written using natural language and contains assumptions made during its construction Plays fundamental role during the period of activity when the modeler conceives, programs, debugs, and test models Helps users and colleagues comprehend basic outline of the model from their perspective on how the real world operates

Approach cont’d. Domain AnalysisDomain Modeling Dynamic Structure Diagrams Use Case Diagram Sequence Diagram Collaboration Diagram Static Structure Diagrams IS-AHAS-AAssociations Problem Domain

14 The Formal Model Unambiguous description of model structure separated from software implementation Useful once users and colleagues understand informal model and want more detail Used as an aid to detect omissions and inconsistencies and resolve ambiguities inherent in informal models

15 Problems of Conceptual Modeling No hard and fast rules concerning model formulation (Uncertainty for both the developer and user) –What does a Conceptual Model look like? No magic formulas governing what should be included in a model in the form of variables and parameters, descriptive relationships and constraints, or criterion for judgment of effectiveness (Lack of Standardized Processes) –What should a Conceptual Model contain? Nobody solves the problem, rather everybody solves the model that they have constructed of the problem (Diversity and Inherent Incompatibility) –What technique to use? UML, DoDAF, IDEF0,….

16 Relationship with Base Object Models BOMs capture key views of a conceptual model as: –Entity or event types (Static descriptions) –Patterns of interplay and State Machines (Dynamic descriptions) Used as a building block for composable simulation environments. Payoff for Conceptual Modeling—An End State —or a standardized formal model

17 SCM SG Goals Research the use of conceptual modeling in the M&S or related information technology domains Perform exploratory work into the establishment of best practices for simulation conceptual modeling Establish recommendations for persistent management of the topic within SISO

18 How to Accomplish Goal #1 SCM SG will research the use of Conceptual Modeling in M&S and related information technology domains –Make a data call for readily available empirical evidence to create a set of best (most-effective) practices Data Calls –Partially successful –Could always use more data Provide SCM SG documents through SISO web site

19 How to Accomplish Goal #1 Issued to SCM SG reflector just prior to SIW (30 March 05) –Received Responses from Susan Solick Don Timian Jim Weiner Vahid Mojtahed Nathalie Harrison Tommy Nordqvist Averill Law

20 How to Accomplish Goal #2 SCM SG will perform exploratory work into establishment of best practices for Conceptual Modeling –Identify and evaluate the significance of the topic to the scope of the SISO and interests of its members –Refine existing Conceptual Modeling terminology –Draft an ontology of concepts –Document relevant techniques and beneficial procedures

21 Plan #2A SCM SG will perform exploratory work into establishment of best practices for Conceptual Modeling –Identify and evaluate the significance of the topic to the scope of the SISO and interests of its members –Refine existing Conceptual Modeling terminology –Draft a taxonomy of concepts –Draft Simulation Conceptual Modeling Vision Statement Introductory Statement SCM topics to be addressed SCM terminology requiring definition and/or refinement SCM concept taxonomy

22 Introductory Statement A simulation conceptual model is an abstraction from either the existing or a notional physical world that serves as a community of interest (COI) frame of reference for further simulation development by documenting simulation and implementation independent views of important entities, their relationships, key actions, interactions and properties. A simulation conceptual model describes what the simulation will represent, the assumptions limiting those representations, and other capabilities needed to satisfy the stakeholder’s requirements. It is a human and machine readable bridge between these requirements, and simulation design.

23 SCM Topics to be Addressed Justification - Indication of the value added by a conceptual model (business case for CM) - Method to keep on track designer and developer - Identification of stakeholders - Impact of conceptual models upon stakeholders - Ability of conceptual model to address relevancy of real world components -Conceptual model only artifact to document relevancy of real world upon interactions where otherwise not recognized -Part of KA and simulation / model validation process

24 SCM Topics to be Addressed Methodology - Advance the understanding of a conceptual model, their creation and use process, goal to increase stakeholder’s requirements in final solution. - Variety of formats (UML, animated powerpoint, word documents) needed communicate between stakeholders - Archivable products, persistent for community - Common thread of components of well-formed conceptual models (tools, critical mass of end user content, strategy and manage reusable items, training) - Reuse of legacy simulators - Provision of a roadmap to reverse engineer conceptual model for legacy simulations - Future vision of utility of conceptual model - Reuse of systems/simulation engineering processes and products - Bottom-up or top-down development of conceptual models - Rationale for layering of conceptual modeling (national, commercial security interests) - Boundaries of conceptual model (conceptual, design, implementation) - How to effectively test requirements throughout the design of the simulation federation to ensure requirements are indeed the “right ones”

25 SCM Topics to be Addressed Relationships - Provide support for VV&A - Applicable to community broader than DoD audience (game developers, OMG Computational Independent Model development) - Relationship to other SISO PDGs (BOM and VV&A Overlay) - Relationship to high level simulation development processes (e.g. IEEE FEDEP Recommended Practices Guide)

26 SCM Terminology to be Defined Model Modeling Simulation Simulation conceptual model Purpose(s) Requirements (Users, System) Identify Audiences Stakeholders Domain space Referent Representation Abstraction Capture Describe Assumptions Limitations Resolution Fidelity Consistency Composability Interoperability Pattern(s) Layering Validation of conceptual model Well-formed CM Credibility Legacy simulation/simulator Evolution

27 SCM Taxonomy of Concepts Stakeholder perspectives Requirements artifact vs design artifact Formal vs informal Requirements definition and traceability Methodology of establishing credibility Configuration management of CM (timestamping) Evolutionary nature of CM (changing uses for CM over time) Support to ancillary documentation

28 SCM Taxonomy of Concepts Types (formats capture and presentation) of CMs Range of conceptual model uses Purposes of CMs Scope of CM, e.g. federation vs federate (stand alone or associated execution) Common frame of reference for CM Fidelity resolution (level of detail / level of abstraction / decomposition of M&S domain space) Attributes or characteristics of a CM Communication pathways internal and external (technical and management) Coherence (consistency) between CM views Assumption of composability for CM Independence from implementation, application specificity

29 Plan #2B SCM SG will perform exploratory work into establishment of best practices for Conceptual Modeling –Document relevant techniques and beneficial procedures –Guide to Conceptual Modeling referencesGuide to Conceptual Modeling references –Listing of SIW Papers –Bibliography of Books –Pointers to Online Resources

30 How to Accomplish Goal #3 Consolidate the findings of the topical committees and establish recommendations for persistent management of the topic within SISO –Final Report to SAC Prepared for Fall 05 SIW Circulate via reflector for 30 days –The Way Forward Standing Study Group (SSG) Wait until competing PDG activities finished (HLA Evolved, BOM)

31 SISO SAC Groups Study Groups (SGs) –SISO SGs are created as the result of a Terms of Reference (TOR) –SGs are chartered to answer questions of interest to the M&S community –SGs have a limited life; generally 1 to 2 workshop cycles –SGs can be first step to a PDG

32 SISO SAC Groups Standing Study Groups (SSGs) –SISO SSGs are created as the result of a Terms of Reference (TOR) –SSGs are chartered to provide long-term support to an existing standard mature a potential standard Potentially to provide support to open-source software –SSGs will provide an annual report to the EXCOM through the SAC describing their progress over the previous year describing their goals for the following year due 1 st September (each year) for consideration during the Fall SIW

33 Long Term Goals Formulate a CM Recommended Practices Guide as a balloted community product as an extension of the FEDEP Provide input for DMSO VV&A Recommended Practices Guide web site Provide a sound foundation for related SISO development groups

Reference FOM Study Group BOM Methodology Strawman SRML Rapidly composable and scalable M&S 2001 BOM Study Group 1996 RPR FOM HLA 1516 FOM “piece parts” (FEDEP, OMT) BOM PDG FEDEPPDG CMSE BOM PN 2004 History SISO-STD BOM Spec Vol 1 Interface BOM IF BOM Spec Guidance Doc ECAP BOM Spec 2005… Tools Components Repositories HLA 1516 Evolve “As long as things are created from scratch, growth can be at most linear”

35 Summary The SCM has established a foundation for a Standing Study Group Previous product development experience has shown that this will be a lengthy process Several challenges remain –To continue moving forward –To increase visibility of activities within M&S community –Secure support for SCM PDG ($, €, £, CAD)

36 Backup Slides

37 Introductory Statement A simulation conceptual model is an abstraction from either the existing or a notional physical world that serves as a frame of reference for further simulation development by documenting simulation and implementation independent views of important entities, their relationships, key actions and interactions. A simulation conceptual model describes what the simulation will represent, the assumptions limiting those representations, and other capabilities needed to satisfy the stakeholder’s requirements. It bridges between these requirements, and simulation design. −Vahid Mojtahed

38 Introductory Statement A simulation conceptual model is an abstraction from either the existing or a notional physical world that serves as a frame of reference for further simulation development by documenting simulation and implementation independent views of important entities, their relationships, key actions, interactions and properties. A simulation conceptual model describes what the simulation will represent, the assumptions limiting those representations, and other capabilities needed to satisfy the stakeholder’s requirements. It bridges between these requirements, and simulation design. −Nathalie Harrison

39 Open Discussion Topics Reaffirm the need Strategy –Create Vision Statement leading to Strawman Long term process, a lot of work to be done –Create Accessible Listing of Conceptual References Short term product, enhance quality and utility over time Revision to Vision Statement

40 Additional Vision Statement Comments “Scenario Dependence” –Our work shows that without a "scenario" you can never know the domain in focus and therefore have no chance to have a practical approach to actually do conceptual modeling. All conceptual modeling begin with some sort of “focused context”. So our understanding is however a conceptual model can be both simulation-independent and implementation-independent, they are scenario-dependent, those important entities, relationships, actions and interactions has their means in the context of the scenario. - Vahid Mojtahed –Regarding the "scenario dependence", I would rather say that it is "community-of-interest (COI) dependent" since "scenario-dependence" may prevent reusability. It is probably what Vahid intended to mean. - Nathalie Harrison

41 Additional Vision Statement Comments “Readability” –And regarding the last sentence in the Introductory Statement: “It bridges between these requirements, and simulation design." There should perhaps be some kind of addition that the conceptual model, in order to bridge between the requirements and simulation design, also must be user readable. - Vahid Mojtahed –Vahid also added that the conceptual model must be user- readable. I would also add that its should be "human and machine readable". If we want to achieve the Model Driven Architecture (MDA) philosophy in the future that says that concepts must be linked automatically to the implementation. - Nathalie Harrison