Introduction to the Data Model
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Why use standards
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Each platform that wants to integrate with the BDA environment will have its own Data Model. In order to ensure an open and modular architecture,
the Data Model chosen for the BDA is a combination of the existing information standards |ISO 10303-233| and |ISO 10303-239|. This has the advantage that
there are already a number of tools and implementations available that are based on these standards. It also provides a communication mechanism to systems
outside of the BDA environment, and an archive format for BDA data.

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What are ISO 10303-233 and ISO 10303-239?
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* |ISO 10303-233| Systems Engineering
	* AP233, as this standard is commonly known, defines standardised Systems Engineering Data Structures for use in data exchange and sharing. AP233 supports the "early phases" of product design, such as requirements and systems management through detailed design to verification and validation processes.
* |ISO 10303-239| Product Life Cycle Support (PLCS)
    * PLCS, as this standard is commonly known, defines standardised Product Life Cycle Support Data Structures for use in data exchange and sharing. PLCS supports the later phases of product life, from detailed design to deployment, operation and de-commissioning. It is a companion standard to AP233 and shares 70% of the data definitions with AP233. PLCS edition 2 is currently under development and uses even more of the AP233 structures.
        
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Mapping between the Business Object Model and the Data Model
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The mapping of the Business Object Model to the BDA Data Model is being developed by CRESCENDO as part of the |OASIS PLCS standard|.

The mapping is being documented as a PLCS Data Exchange Specification [DEX] using the SourceForge |PLCSlib| project under the CRESCENDO context.

This forms part of D5.1.3: BDA Standards Recommendations. 

Templates, corresponding to CRESCENDO Business Objects, are defined to support the specification of the DEX. These templates, as part of their formal
specification, are mapped to an |OMG SysML| representation of |ISO 10303-239|:2011 Product Lifecycle Support [PLCS PSM].The mapping uses |OMG SysML| Parametric

Diagrams to decompose the Templates (representing the CRESCENDO Business Objects) into OASIS templates or PLCS PSM Data Model elements. Binding connectors
are used to specify how attributes or properties of the Business Objects are represented in the Data Elements. The mapping is in progress, but an example
of a typical OMG SysML Parametric Diagram is shown below.
   
.. figure:: /objects/images/dex_template_amn.png
	:scale: 100%
										
	The SysML Block Definition diagram showing how a Model Instance relates to other objects to represent an Associative Model Network
	
.. sectionauthor:: |Judith Crockford|

.. include:: /objects/documents/main/Keywords.rst