The Special Role of M&S in Cross-COI Mediation

1. The Special Role of M&S in Cross-COI Mediation Bernard P. Zeigler, Ph.D., Arizona Center for Integrative Modeling and Simulation and Joint Interoperability Test Command Fort Huachuca, AZ 85613-7051 zeigler@ece.arizona.edu

2. System Entity Structure • The M&S COI has a special role to play in the area of mediation among metadata schemes developed by the various COIs • Interoperability among the web services of COIs will require a more dynamic elements and associated simulation interpretations, typical of the M&S concerns • Use System Entity Structure (SES) from Theory of Modeling and Simulation • The SES is the basis for a methodology, and practical tool set that supports data engineering and modeling of application domains with hierarchical system characteristics • It is being applied by the Joint Interoperability Test Command (JITC) to imagery metadata characterization for the some of the sensor products of the National Geospatial-Intelligence Agency (NGA).

3. SES Overview • SES methodology and tool set • Java classes using Sun’s XML classes • develop well-structured, hierarchically composable data models • can be mapped to a variety of legacy formats. • Due to its fairly simple axiomatic structure the SES lends itself to tool-supported structure analysis • tools to compute the common elements and substructures of a pair of SES representations. • not as powerful as a full-blown, logic-based ontology framework • it is sufficiently expressive for real application • sufficiently well structured to allow useful tool support.

4. System Entity Structure –Basic Concepts • Entity – a thing in the real world, e.g book • Variable – an attribute of an entity, e.g. title • Aspect – decomposition, a way to break down an entity into parts or components (entities), e.g., front cover, back cover, pages • Specialization – a classification, a way to classify an entity into special cases or subclasses, e.g., genre • MultipleAspect – a decomposition into similar parts, e.g. pages • Entities alternate with Aspects and Specializations • Prunings generate family of pruned entity structures (PES)

5. Example: SES Representation of Book book Entity Specialization genre Aspect physicalDec contentDec pages chapters front cover back cover bio- graphy fiction page chapter chapterDec MultiAspect explanation theorems fiction_book theorem pruning physicalDec proof example front cover pages back cover page1 page100

6. Generation of XML Schema

7. Synthesizing Large SESs and PESs From Components SES merge merged SES PES merge merged PES

8. Top Level SES Representation of NITF Core Information Mission Mission Image Aspect Images Image Aspect Image Image Data Aspect Segment descriptions Sensor Ground reference Identification

9. Identification Identification Data Aspect Original Image Data Date/Time Data Image Sequence Image Sequence Data Aspect Sequence ID Simultaneous Collection ~ISID ~NRG ~NCG ~TRG ~TCG SES Breakdown of Identification Information

10. Mission Mission Image Aspect Images Image Aspect Identification Image Identification Data Aspect Image Data Aspect Original Image Data Date/Time Data Image Sequence Image Sequence Data Aspect Segment descriptions Sensor Ground reference Identification Sequence ID Simultaneous Collection ~ISID ~NRG ~NCG ~TRG ~TCG Identification Entity Merged Into Mission SES

11. Advantages of Hierarchical Methodology for Managing Body of Standards • Divide and Conquer - Complex standard is decomposed into smaller more manageable pieces • Pieces can be developed and maintained individually as modifications are required • Builds (merges) can be performed at any time to create current version of overall standard • Some pieces can be stand-alone standards under the same or other authorities • XML instances of component standards can be merged into larger XML instances of the overall standard.

12. Approach to Harmonization • Multiple legacy metadata formats that partially overlap in their referents • Attempt to find as much common core as possible • Express common core in SES • Expland SES with Specializations to capture non-core elements • Re-derive original content of metadata by pruning from master SES

13. Tools for Harmonization • Relational representation of SES • Commonality measures • Operations to increase commonality • Thesaurus

14. entities aspect 0..n 0..n aspects attributes 1 1..n multi aspects specializations Relational Representation of SES 0..n 0..n 1..n attribute entity multi-aspect 1 1 0..1 1..n 1..n SES 0..n 0..n specialization SES can be represented as a collection of relations such as entityHasAspect, aspectHasEntity, entityHasSpecialization, etc. as shown. SES’s can be compared on the basis of their relational representation.

15. Finding common entities and SES’s entities entities SES A SES B common entities

16. Computing Commonality of SES’s equality of subSES below common entity ? SES A common entity common entity subSES below common entity SES B • Commonality = • fraction of shared entites • fraction of shared sub-SES’s

17. Entity Removal May Increase Commonality House House Living Room couch removeEntity (“LivingRoom”) House House Living Room sofa

18. Name Substitution may Increase Commonality House House couch couch House House addRename(“sofa”,”couch”) replaceAll() sofa couch

19. Maintaining Thesaurus of Equivalent Names Representatives of equivalence classes are canonical names that will be used as defaults in application to SES’s, thereby providing a standard version of an SES. set representatives for equivalence classes House apply to SES thesaurus sofa thesaurus.xml addRename(“sofa”,”couch”) replaceAll() store in persistent form House transfer pairs couch

20. Dynamic SES • Need metadata that tracks processing as data is processed through stages • Develop dynamic SES that can evolve through transformations • Include forward and reverse links for traceability

21. Dynamic Process Example: Evolution of a Book Book (concept) Book (content description) Book (physical embodiment) Book (revisions) Book (re-printings)

22. Ex: Representing Versions In SES chapterDec book contentDec theorems engineering version – remove all proofs from theorems chapters theorem chapter example chapterDec mathematician’s version – remove all examples from theorems chapterDec explanatory theorems theorems theorem theorem proof example proof

23. Trajectories in Space of SESs Book SES’ Book SES transformation retain description of transformation to enable reverse traceability Space of SES’s edges labeled by transformations and ancestor links nodes are SES’s derived from precursors

24. Summary • SES is rich enough to support approaches to harmonization and dynamic processing that will be involved in cross-COI mediation • Representation as relations allow Java operation and measurement tools • Supports alternative Mappings to XML to satisfy different applications

25. Bernard P. Zeiglerzeigler@ece.arizona.eduACIMSwww.acims.arizona.eduJITCjitc.fhu.disa.mil Contact: More information:

26. Joint Interoperability, Assured Security, Best Value, Customer Success Global Net-Centric Solutions -- The Warfighter's Edge