Hierarchical Web-Based Libraries for Modeling: A Comprehensive Overview

1. Model Design using Hierarchical Web-Based Libraries F. Bernardi Pr. J.F. Santucci {bernardi, santucci}@univ-corse.fr University of Corsica SPE Laboratory UMR CNRS 6134

2. Studied Problem • Objective of this work: to build a generic models library • Interests: • Reusability of models seen as modeling components • Ease of new models building • Ease of new models validation • Main Requirements: • Ease of use • Inheritance between models management • Abstraction Hierarchy between models management • Remote access capacity

3. Summary • Basic Notions of M&S • Basics of the Models Library • Web-Based Architecture • Screenshots • Conclusion and Perspectives

4. Summary • Basic Notions of M&S • Basics of the Models Library • Web-Based Architecture • Screenshots • Conclusion and Perspectives

5. Basic Notions of M&S • Three complementary concepts • The Multi-Views concept: • Allows a gradual complexity introduction • Each model of these views represents a particular part of the global system • Structural view, behavioral view, system view,… • The description hierarchy • Allows a recursive subsystems hiding

6. Basic Notions of M&S • The abstraction hierarchy • General problem for modeling: choosing a good level of details • Abstraction level: • Determines the amount of informations contained in a model • Allows taking efficiently into account the relevant informations

7. Basic Notions of M&S • The abstraction hierarchy

8. Summary • Basic Notions of M&S • Basics of the Models Library • Web-Based Architecture • Screenshots • Conclusion and Perspectives

9. Basics of the Models Library • Software Component: • Software object presenting well-defined interfaces • Can be personified • Reusable in different contexts • Modeling Component: • Software component • Can be described following different abstraction levels • Can be « context-in » or « context-out »

10. Basics of the Models Library • Context-in and Context-out models notions: • Context-out model: • Abstraction of a model • Presents a structure allowing it to be stored in a library • Context-in model: • Context-out model extracted from its library • Directly reusable in the environment

11. Basics of the Models Library • Models Library: Object-Oriented architecture allowing to store and retrieve persistent context-out models • Structuration mainly based on two paradigms: • Application domains • Inheritance hierarchy • Provides the abstraction hierarchy management

12. Basics of the Models Library • Core of the architecture: The Storage Engine • Build on the model of an Object-Oriented Database Management System • Uses XML to describe and store models • Modular and extensible: based on the notion of service • Can use six different element types

13. Basics of the Models Library • Six elements able to be stored: • Library: root object • Domains: DEVS Simulation, VHDL Descriptions,… • Application Domains: Science part of the models • Classification Intermediate Models (CIM): allow a classification hierarchy between models • Inheritance Intermediate Models (IIM): storage object allowing the share of properties • Model File: storage object (context-out model)

14. Basics of the Models Library • UML Diagram: Links Between Elements

15. Basics of the Models Library • Service: set of functions for the structuring, the management or the maintenance of a library • Five Main Services: • Name Service • Classification Service • Abstraction Hierarchy Service • Inheritance Service • Persistence Service

16. Basics of the Models Library • Abstraction Service: • Based on an Abstraction Matrix • Manage relative abstraction levels between context-out models • Inheritance Service • Not performed directly on context-in models • Applied on context-out models • Performed through XML tags

17. Basics of the Models Library • XML-based Persistence Service • Context-in to context-out • Context-out to context-in

18. Summary • Basic Notions of M&S • Basics of the Models Library • Web-Based Architecture • Screenshots • Conclusion and Perspectives

19. Web-Based Architecture • Set of tools allowing a design team to work on the same models stored on a server • Basic idea: two possibilities offered for accessing the storage engine: • Using a Web browser • Directly from the M&S environment

20. Web-Based Architecture • First possibility: simple management, documentation and/or consultation • Second possibility: uses APIs for the M&S environment Web Browser Network Application Server Storage Engine Server Network Application Server Modeling and Simulation Storage Engine Environment Server

21. Web-Based Architecture • Implementation: Servlets/Applets/Java Web Start • Technological Choices: • Servlets: • Persistents • Fasts • Platform-independents • Extensible • Applets: • Very well known • Ease of use • Java Web Start: • Fast • Always up to date

22. Summary • Basic Notions of M&S • Basics of the Models Library • Web-Based Architecture • Screenshots • Conclusion and Perspectives

23. Screenshots

24. Screenshots

25. Summary • Basic notions of M&S • Basics of the Models Library • Web-Based Architecture • Screenshots • Conclusion and Perspectives

26. Conclusion and Perspectives • Main Points and Originalities: • Inheritance Links • Abstraction Links • Traduction of DEVS models in XML • Validation using the JDEVS environment: • Environmental Studies • CORBA Architecture Study • Perspectives: • Management of other modeling formalisms • Improvement of the performances of the storage engine • Study of the distribution of storage engines on a network