DEVS Modeling Language (DEVSML)

Saurabh Mittal, José Luis Risco Martín
{saumitt, jlrisco}@gmail.com

This work is built on the JAVAML research done by Vladimir for DEVSML. It was pursued independently by Jose Luis Martin that resulted in DEVSML with a smal behavioral support. The present work aims to integrate these two approaches and provide complete behavioral support to DEVSML by implementing the proposed universal Atomic and Coupled DTDs. We look forward toward standardization of these DTDs so that models across the web can participate in Dynamic Modeling & Simulation over Net-centric web services.

DEVSML is a novel way of writing DEVS models in XML language. This DEVSML is built on JAVAML, which is infact, XML implementation of JAVA. The current development effort of DEVSML takes its power from the underlying JAVAML(earlier work by Vladimir) that is needed to specify the behavior of atomic models. We now have the capability to write DEVS models in DEVSML, both atomic and coupled through the developed DTDs. The DEVSML models are tranformable back'n forth to java and to DEVSML. It is an attempt to provide interoperability between various models and create dynamic scenarios. The key concept is shown in the figure below:



Figure 1: Basic concept with respect to Automation of DEVS models using DEVSML


Figure 2: DEVS Transparency & Net-centric Model Interoperability using DEVSML Layered Architecture



The concept shown above is based on DEVSML Layered architecture that promotes DEVS transparency. The basic concept is a part in overall web enabled infrastructure where such atomic models are dynamically coupled and simulated over SOA. Development is underway to make the DTDs SOA capable. The figure below shows various other acronyms like DoDAF, which is Department of Defense Architecture Framework. The present work aims to empower DoDAF with a repository of 'interoperable' models defined under DEVS Formalism. More details on the approach can be found in references section. [1,2]



Figure 3: Process Methodology showing how automated modeling using XML can provide M&S to DoDAF documents


Finall this work is a part of the overall DEVS-DODAF Testing & Evaluation Strategy where M&S is integrated enough to be a part of design process [3].


Example

Coming in next version:
1. Integration with DoDAF documents
2. Dynamic composition of DEVS model using URL and web-repositories



Application Archives

Ver. 2.0 (August 20, 2006): WEB SERVICE Implementation

Web-client Applet accessible here
Client .exe application accesible here
(download and run it on any machine with latest JRE).
Client .jar application accesible here (download and run it on any machine with latest JRE).
(All the client applications above communicate with the services resting at ACIMS Server)

The following snapshot shows the java application Ver. 2.0 that demonstrates the following:
1. Five Web Services that :
       a. Convert Java model to DEVSML
       b. Convert DEVSML to java code
       c. Validate the existing DEVSML model
       d. Integrate coupled and atomic DEVSML models towards a portable 'Composite' Coupled DEVSML file that is Simulatable at any remote server
       e. Simulates the Composite Coupled file and sends console messages at Server to Client window giving evidence of simulation running.
2. Server rests at ACIMS lab that provides these Services
3. User can select his own Source and Target directories
4. User can choose his chosen implementation i.e. java code and Simulator compatibility. The system checks for compatibility as well.
3. Implements all the functionality in the version 1.4



Figure: Web Service Implementation of DEVML in Version 2.0

Download Ver 1.4    (August 5, 2006)

The following snapshot shows the java application Ver. 1.4 that demonstrates the following:
1. Contains two simulator operability i.e xDEVS (Spain) and GenDEVS (ACIMS-USA) demonstrating validation of DEVSML atomic and coupled models with same Atomic and Coupled DTD
2. Converts any atomic/coupled model from their JAVA implementation to DEVSML transformation and vice-versa
3. Validates any DEVSML model description
4. Integrates any coupled DEVSML description into a composite DEVSML coupled model ready to be simulated with corresponding simulator
5. Generation of JAVA code library from a composite DEVSML coupled model.

Sample Operations and things you can do with this download (Instruction Manual):
  1. You can convert it to DEVSML implementation using one of the red radio buttons. The system will check automatically if it is Atomic or Coupled description.
  2. Convert an Atomic/Coupled DEVSML description to corresponding JAVA model. The system will check if the DEVSML description is compatible with the Simulator selected and will throw an error if wrong Simulator is selected.
  3. Integrate a Coupled DEVSML description with Atomic java files thereby generating a Composite Coupled DEVSML description. A Composite Coupled model is defined as a Coupled model in DEVSML that contains the behavior inside the Coupled model itself and is portable in its entirety as a ‘Scenario’.
  4. Convert a ‘composite’ Coupled DEVSML description to corresponding JAVA model, thereby generating the atomic JAVA models simultaneously. All generated files will be reflected in the Target folder.
  5. Validate any Atomic/Coupled DEVSML description, independent of any Simulator selection as there is one unique DTD each for Atomic and Coupled description.


Figure: Application snapshot showing DEVSML implementation interface

Download Ver 1.0    (July 26, 2006)

The following snapshot shows the java application Ver 1.0 that demonstrates the following:
1. Specify a coupled model in DEVSML (AtractorLorentz.xml)
2. Integrate a coupled model in DEVSML with other atomic models specified in JAVA (Function.java, Integrator.java, Scope.java)
3. Observe the generated atomic DEVSML files (Function.xml, Integrator.xml, Scope.xml) from the integration process as 'artifacts' (that can be stored in repository)
4. Generate DEVSML to JAVA and vice versa.


Version 0.9              (July 22, 2006)
          Problems with this version
          1. Path error. Application not being able to find correct path on user directory
          2. No error checking with respect to Atomic/Coupled DEVSML files

References:

Concept:
XML-Based DEVS ~ DEVSML:
Automation using XML Enhancing DoDAF Use for DEVS-Based Testing & Evaluation (pdf)


Working Papers
    •     Jose Luis Risco Martin, Saurabh Mittal, Miguel Angel Lopez Peria, Jesus Manuel de la Cruz Garcia, A W3C XML Schema for DEVS Coupled Scenarios  
    •    
Saurabh Mittal, Jose Luis Risco Martin, DEVSML: Automating M&S with JAVAML
    •     Saurabh Mittal, Jose Luis Risco Martin, Bernard P. Zeigler, Automating DEVS-DODAF Test & Evaluation Methodology using DEVSML

Referenced Papers
   •     Vladimir Janousek, Petr Polasek, Pavel Slavicek, Towards DEVS Meta Language
   •     Saurabh Mittal, Amit Mitra, Amar Gupta, Bernard P. Zeigler, Strengthening OV-6a Semantics with Rule-based Meta-models in DEVS/DoDAF Based Life-cycle Archictectures Development, IEEE-Information Reuse and Integration (IRI06)     Conference, special section on DoDAF, Hawaii, September 2006 (pdf)
    •     Saurabh Mittal, Extending DoDAF to Allow Integrated DEVS-based Modeling and Simulation, (under review) submitted to Journal of Defense Modeling and Simulation JDMS, 2005 (pdf)
    •     Saurabh Mittal, Eddie Mak, James J. Nutaro, DEVS-Based Dynamic Model Reconfiguration and Simulation Control in the Enhanced DoDAF Design Process, (under review) submitted to Journal of Defense Modeling and Simulation JDMS, 2005 (pdf)
    •     Bernard P. Zeigler, Saurabh Mittal, Enhancing DoDAF with a DEVS-based System Lifecycle Development Process, In Proceedings of IEEE International Conference on Systems, Man and Cybernetics, SMC05, Hawaii 2005 (pdf)


Last Updated: August 5, 2006.