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Lets conceptually describe the VCA model using the UML with use case diagram.

As an actor, in the development mode, acts the engineer of the top-level of "ACS TP" setting, in the execution mode the operator.

In development mode lets select the following options of using the VCA:

Use case diagram for operation of the VCA in development mode is shown in Fig. 4.2.1.

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Fig.4.2.1 Use case diagram of the VCA in development mode.

Using variants in the execution mode:

Using diagram of the VCA in the execution mode is shown in Fig.4.2.2.

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Fig.4.2.2 Using diagram of the VCA in the execution mode.

Any VCA can operate in two modes the development and running. In the development mode the VCA interface and its components are formed, the mechanisms of interaction are identified. While the running it is carried out the formation of VCA interface based on the developed VCA with the final user interaction is made.

VCA interface is formed of the frames, each of which, in its turn, formed from elements of the primitives, or user interface elements. In doing so, the user interface elements are also formed from the primitives or other user elements. That gives us a hierarchy and reuse of already developed components.

Frames and user elements are placed in the libraries of widgets. The projects of the interfaces of the final visualization of the VCA are formed from these libraries' elements. Based on these projects the visualization sessions are formed.

The structure of VCA is shown in Fig. 3.

Generalized structure of the VCA. (214 Kb)
Fig.3 Generalized structure of the VCA.

This architecture of the VCA allows the support of three levels of complexity of the developing process of the management interface: