Software design

The documentation on the software requirements shoirld be prepared according to standards whose formaUty should not preclude readability. The documentation on the software requirements should be verifiable and maintainable. The use of a formal specification language may help to show the coherence and completeness of the software requirements. 

Additional detailed guidance on the documentation and style of the documentation on the software requirements can be foimd in international standards for high reliability software used in safety systems in nuclear power plants [5]. 

The architecture of the software refers to its organization into modnles. These modules include processes, abstract data types, communication paths, data stmcmres and display templates. There are munerous methods of dividing the software into modules with differing emphasis on particular kinds of module. The choice of architecture is very important in determining the simplicity of the modnles and of the interactions between them, which in timi determines the simplicity of their specifications and of the verification and validation tasks. 

The way the modules fit together (the software architecture) can be described in more than one way, even within a single design. This Safety Gnide does not recormnend any particular way of representing the software architectnre. 

At least two levels of design ate recommended the architecture of the software and its detailed design (for more detailed recommendations, see Section 5.1.1 of Ref [4], and standards and technical books on software engineering). The required attributes of software design are discnssed in paras 8.5-8.12. 

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One way to model a solid is to use software designed for gas-phase molecular computations. A large enough piece of the solid can be modeled so that the region in the center for practical purposes describes the region at the center of an inhnite crystal. This is called a cluster calculation. 

Many more special-purpose software packages have been developed, particularly in teaching and research institutions. SMCM is software designed at the University of California in Los Angeles for partitioning of pollutants (19). Monte Carlo and molecular dynamic techniques have been adapted in a... 

Software failure Eollow strict controls throughout the software resulting in haz- life cycle including requirement specifications, ardous event. software design, coding, testing, and... 

Software designed for general or specific use might be useless in the intended application sociologists, mathematicians, clinical researchers, and physicists, just to name a few user categories, all gather and analyze data, to be sure, but each one has particular data structures and hypotheses. Tests must be selected to fit the application. 

For purposes of this paper, the term "Data System" will refer to computer software designed to acquire data from an instrument or laboratory process, to manage and access that data, to analyze the data as required, and to plot and report the data and analysis results. 

Contextual design is a flexible software design approach that collects multiple customer-centered techniques into an integrated design process [7]. The approach is centered around contextual inquiry sessions in which detailed information is gathered about the way individual people work and use systems and the associated information flow. The data from each contextual inquiry session are used to create sequence models that map the exact workflow in a session along with any information breakdowns, flow models that detail the flow of information between parties and systems (much akin to but less formal... 

Software designed to normalize spectra to database standards. (Step 7)... 

Encouraging a broader application of Al methods, this seminal work gives software designers a clearer picture of how scientists use Al and how to address those needs, and provides chemists, biologists, physicists, and others the tools to increase the speed and efficiency of their work. 

Includes an unprecedented set of supporting software designed with simple graphical user interfaces that allow readers to tackle common problems... 

Separating the data transformation into three distinct steps enforces a completely modular software design. In practice, the data transformation is executed via command shell scripts, using freely available software for both the XSLT transformation and XSD validation. The raw data contained in the 39 surveys in the New Brunswick compilation are exported into 7,000 individual KML files, which can be viewed online at http //gdr.nrcan.gc.ca/geochem. 

This book gathers together some of the techniques we see as necessary for that movement into a coherent kit. To make component-based development work, we need our best skills as software designers, and we need to reorganize the ways in which software is produced. 

The techniques we have seen can be used to describe the interactions that occur within a business or they can describe the actions performed by a software system or component or—the simplest case—they can describe the operations performed by an individual object within a software design. That is what we will look at next. 

In a joint action, some of the parameters may be distinguished as participants and drawn linked to the use case pictorially, whereas other parameters are written in text style. For example, in Figure 4.5, buyer and vendor are participants, whereas item is a parameter. In business analysis, the difference is a matter of convenience and is analogous to the equivalence of the associations and attributes of object types. In a software design, the participants can be used to represent objects that we know will definitely exist in the final code and that will, between them, take responsibility for executing the action. The list of parameters, on the other hand, represents information transferred between them whose implementation is yet to be determined. 

Joint actions are useful for describing business interactions, interactions within a software design, and interactions between users and software. We like to separate the specification of an action from its refinement into smaller actions. 

One business model may be common to many component designs. For example, an insurance company with many products and procedures may construct a business model to gain a clear understanding of what goes on in the company. The model can be used both to help improve the business organization and to serve as the basis for the specification of various support software. The business model will therefore be unbiased toward any particular software design. 

Within a software design, the different levels of refinement are generally associated with different, decoupled layers in the software. We can see this, for example, in the conventional separation into business and GUI layers. We can also see it in communications protocols, from the individual bits up through to the secure movement of files and Web pages. 

Something like 70% of work on the average software design is done after its first installation. This means that an approach, such as reuse, aimed at reducing costs must be effective in that maintenance phase and not just in the initial design (see Figure 11.1). 

Predefined context design. Throughout this study, we conjecture that we re concerned with building a computer System that will work within some human context. Of course, many of the contracts that software designers have with their clients or employers are about building components within a larger piece of software or a system embedded within a complex design of many pieces of hardware. 

Conform to the spec we have this in common with all methods of software design. 

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