High-level specification

An overview with high-level specifications was presented by the firm in support of validation. However, this document was not a controlled record and it lacked review and approval. [FDA 483, 2001]... 

The first step toward the creation of mappings between two schemas was to understand how the elements of the different schemas relate to each other. This relationship had to be expressed in some high level specification. That specification was materialized in the form of correspondences. 

Identify the ways a reconstituted supply chain should support the strategy. Set a high-level specification for the new supply chain and its role. Divide the supply chain into processes. Examples include order fulfillment, payments, inbound material, physical distribution, production control, and new product introduction. List possible changes to the processes needed to meet strategic requirements. 

At first we wrongly modeled UCM as an automaton without a tfansition from location ack to A. Also the guard of the transition from ack to req is not x== delay id ==0, but x=delay. Such a small defect leads the result of model checking to fail. Therefore, model checking on a high-level specification is very useful to avoid unwanted design. 

The implications of the unified representation for high-level specification seem to all be beneficial. One of these benefits is that the representation supports synchronous and asynchronous behavior equally well through the use of an asynchronous communicating processes model. Input data becomes available, is operated upon, and output data is made available. The use of specialized description methods for the interface and data-flow behavior is encouraged by the clean separation between the two portions of the graph. For example, an HDL with send and receive constructs can be used to describe the data-flow and timing diagrams can be used to represent the interface details. The interconnections between the two are made between the data event nodes on the interface and the send and receive operation nodes in the data-flow. Of course, the basic block structure of the description must be identical in the two representations. 

T. Meng, R. Brodersen, and D. Messerschmitt. Automatic Synthesis of Asynchronous Circuits from High Level Specifications. IEEE Transactions on Computer-Aided Design of Circuits and Systems, 8(11) 1185-1205, November 1989. 

Fig. 8 shows a dataflow graph consisting of additions and subtractions and the corresponding data dependencies. The labels Ml to M3 indicate mutual exclusive operations and are extracted from the if-then-else structure of the high level specification. Operations with label Ml are always executed and operations with label M2 and M3 are mutual exclusive. 

A practical tool is described which enables the user to extract high level specifications firom existing source codes, using semantic preserving formal transformations. A brief ovoview of the theoretical foundation is given. Extensions are then described to support the acquisition explicit timing information frmn real-time source codes. 

There is then a motivation to examine the existing code, to explore its safety critical properties. The project described in this paper addresses one aspect of this I blem, the extraction of high level specifications from real-time code, in order to ... 

More recent theoretical work has suggested that the feasibility of modelling concurrent programs in such a way that existing transformations can be applied to them to obtain high level specifications. It is planned to study this further, and to extend the Maintainer s Assistant tool, over the next few years. 

This has been highlighted as part of the high level specifications of the plant enterprise engineering environment PEEE. 

MMB89] D. G. Messerchmitt, T. H.-Y. Meng, and R. W. Brodersen. Automatic synthesis of asynchronous circuits from high-level specifications. IEEE Transactions on CADIICAS, Vol. 8(No. ll) pp. 1185-1205, November 1989. 

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