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||Date: 2010/02/10 16:32:29
This technical description of Capabilities describes the purpose of Capabilities and their
relationship to other PLCS components.
Capabilities provide guidance on how the IS0 1030-239 PLCS information model and associated
Templates should be used.
They correspond to the "chapters" of a notional PLCS usage guide within which a set of
Templates are documented, which are then reused by multiple DEXs as shown in Figure 1.
Figure 1 — The usage of Capabilities and DEXs.
A description of how EXPRESS entities are used to represent a given concept
(a specific "functionality" or "capability").
It provides guidance and rules on what Entities
should be used to represent a given concept,
how the entities should be related, and what Reference Data should be used.
As well as general guidance, a set of Templates are documented within a Capability to provide
precise specifications of which Entities should be instantiated to represent
The concepts represented in the Capabilities are generic business level concepts
(such as a "part" or an "approval") whose meaning is agreed within the
PLCS OASIS community and is common to most applications of PLCS but which are not specific to a particular industrial
The Capability description is both graphical and textual to facilitate human understanding and
consists of a business overview and a detailed description of the usage of the information model
Reference Data classes.
Capability also documents a set of one or more "Templates".
Each Template provides a precise, computer interpretable specification of which PLCS entities are required
and how they should be populated.
See the Templates section for further details on Templates.
Examples of Capabilities in PLCS are:
The structure of the Capability is as shown in Figure 2 and comprises:
- a subset of the information model that can be used to define a particular business term;
- a definition of the information model;
- usage guidance for the model;
- usage guidance for the Reference Data;
- a set of Templates.
Figure 2 — Structure of a Capability.
In summary, Capabilities:
- ensure (through the Templates) a common interpretation of PLCS;
- avoid multiple dialects of PLCS;
- reduce the amount of guidance documentation for those wishing to use only parts of PLCS; and
- simplify instantiation of the PLCS data model.
Most Capabilities belong to one of three basic types, with the type often reflected in
Capability name. Namely:
Representing - A full set of information required to describe and classify the target.
This would always include the provision for referencing
Referencing - Enabling a DEX to identify a target without the need to
send the complete representation. This would always include the
identification of the target;
Assigning - The ability to attach routine pieces of additional information,
as required, to elements within a representation. (The use of "Assigning"
as the introductory verb to the Capability is not always appropriate and is
therefore not mandated.)
Each Capability is identified within the DEXlib repository by a number, an identifier and a name, e.g.
- number — C001
- identifier — assigning_identifiers
- name — Assigning Identifiers
These are assigned to the Capability in the initial development process.
Each Capability contains:
an introduction, explaining the nature and purpose of the Capability;
a business overview;
a description of the information model used by the Capability,
with examples of its use;
a full specification of the information model used by the
Capability, derived from the relevant AP239 Implementation
a set of one or more Templates.