Computer software system specification

This chapter addresses selected aspects of computer software tools specifically directed toward human performance design and analysis. The majority of tools currently available emphasize biomechanical models, and as such, this emphasis is reflected here. However, a much broader scope in terms of the body systems incorporated is anticipated, and an effort is made to consider the evolution of more versatile and integrated packages. Selected key functional components of tools are described and a representative sample of currently emerging state-of-the-art packages is used to illustrate not only a snapshot of the capabilities now available, but also those which are needed and options that exist in terms of the fundamental approach taken to address similar problems. 

Chemoinformatics (or cheminformatics) deals with the storage, retrieval, and analysis of chemical and biological data. Specifically, it involves the development and application of software systems for the management of combinatorial chemical projects, rational design of chemical libraries, and analysis of the obtained chemical and biological data. The major research topics of chemoinformatics involve QSAR and diversity analysis. The researchers should address several important issues. First, chemical structures should be characterized by calculable molecular descriptors that provide quantitative representation of chemical structures. Second, special measures should be developed on the basis of these descriptors in order to quantify structural similarities between pairs of molecules. Finally, adequate computational methods should be established for the efficient sampling of the huge combinatorial structural space of chemical libraries. 

Regulatory authorities recognize that, in spite of all the control systems put in place, deviations and changes are sometimes inevitable. A robust GMP system includes procedures to handle, review, and approve changes in raw materials, specifications, analytical methods, facilities, equipment, processes, computer software, and labeling and packaging. All the changes have to be documented with references for traceability. 

The software design specification is written by the system supplier and must identify how the supplier intends to provide system software under a software quality assurance plan. The design specification must describe the subsystem software that will make up the computer system software and subsystem interfaces to implement the aims set out in the FDS. Each subsystem should be traceable back to statements in the FDS. 

The system operational qualification performed on the computing technology provides documented evidence of a high degree of assurance that the hardware and software components perform as required by the system specification. This includes the verification that each unit or subsystem of the system operates as intended throughout all anticipated operating ranges. Appropriate personnel must conduct the system operational qualification. 

The computer system specification includes information on how the operation can be controlled using the features in the selected application package. A review of the process must be conducted to familiarize the computer technology supplier and/or developer (external or in-house) with the requirements defined in the requirements specification deliverable. This system view is essential, particularly when the software must interface with other elements such as hardware, people, and databases. The review of the process includes the further gathering of requirements at the system level, and top-level design. 

During each software or system development step, the developer provides documented evidence that implementing the requirements specified in the requirements specification deliverable developed the product. During the design, the in-process (internal) audit must be carried out in order to verify that the design of the computer system satisfies the requirements described in the computer system specification deliverable, and that the code has been developed in accordance with the technical design specification deliverable. 

The FAT provides evidence that the hardware and software are fully integrated, that they operate as indicated in the computer system specification deliverable, and meet the expectations of the user as defined in the requirements specification deliverable. This final formal integration test should be completed in an environment very similar to the operational environment. The system can be subjected to a real-world environment by using emulators and/or simulators which mimic system interfaces. The user s representative should evaluate the supporting documents, the operation, system functionality, and system reliability. 

This citation talks to a core concept of computer systems validation development procedures and system specifications. Note that the firm was not cited for lack of validation testing of the software but for lack of design controls. Effective design controls would have included written design procedures. Adherence to these procedures would have... 

We again consider the distillation unit introduced in Example 1, updated with temperature information for each of the streams, including some that were previously considered to be internal to the system box. The temperatures have been estimated using a physical property estimation system. There are a number of such computer-based tools and most simulation software systems will include property estimation methods. Figure 3 shows these temperatures as well as the results obtained in the mass balance step above. As more streams are included in this diagram, we have new unknowns related to flow rates. Specifically, we now have the vapour stream, V, from the top of the column to the condenser and the liquid reflux stream, L, from the condenser back into the column. The relationship between the liquid reflux stream back into the column and the actual distillate product stream (D) is given by the reflux ratio ... 

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