Browsing by Subject "Computer software - Development"

Now showing 1 - 4 of 4
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    An Estelle compiler
    (1988) Van Dijk, Jacques; Kritzinger, Pieter S
    The increasing development and use of computer networks has necessitated international standards to be defined. Central to the standardization efforts is the concept of a Formal Description Technique (FDT) which is used to provide a definition medium for communication protocols and services. This document describes the design and implementation of one of the few existing compilers for the one such FDT, the language "Estelle" ([ISO85], [ISO86], [ISO87]).
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    Exploiting persistence in CASE technology
    (1997) Figueira, Ricardo
    A Design Workbench has been built for Napier88 [MBC+94] as part of the natural progression towards developing better product systems and improving software construction tools. The system includes a Metamodeller (enabling users to specify the data and process models they prefer), a Model Builder which supports multiple coexisting models and a Target System Generator. Experience using the Workbench has shown that it is easy to use, increases productivity, improves programming standards and facilitates code sharing. This thesis demonstrates the benefits of orthogonal persistence for Computer-Aided Software Engineering by describing an initial design environment and its subsequent extension to include support for multiple co-existing models.
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    HOOD : a Higher-Order Object-Oriented Database model and its implementation
    (1992) Brand, Michael Max; Wood, Peter Theodore
    There is no accepted standard for the object-oriented database paradigm at present, which has led to different definitions of features and conformance requirements. HOOD is a Higher-Order Object-Oriented Database system which defines a meta-data model for specifying the requirements of an Object-Oriented Database, which provides uniformity and extensibility. From this specification and by making use of a comprehensive structure system, an exemplar or implementation model is defined. Among the constructs provided by the model are types, instances, objects, values, methods, base types, generic types and metatypes. The mechanisms of instantiation and subtyping allow for relationships between these constructs. Extensibility is provided in the model for types, base types, structures and methods. Uniformity is achieved by defining all constructs as instances and through the use of messages for all operations. There is only one form of object construct which provides persistence and identities. The complex values and extensibility of the model allow it to adapt in order to model the real world instead of adapting the real world to fit the model. We have implemented a subset of the structures and values defined in the model, provided persistence and identities for object, and included the various constructs mentioned above. The method language allows for the specification of methods, the passing of messages, and the use of complex values. The compiler performs type checking and resolution and generates instructions for an abstract machine which manipulates the database.
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    SSDE : structured software development environment
    (1990) Norman, Michael John; Berman, Sonia
    Software engineers have identified many problem areas regarding the development of software. There is a need for improving system and program quality at design level, ensuring that design costs remain within the budget, and increasing the productivity of designers. Structured Software Development Environment (SSDE) provides the system designer with an interactive menu-driven environment, and a framework within which he can conveniently express and manipulate his proposed solution. This representation is in terms of both a conceptual model and a detailed software logic definition. Thus SSDE provides tools for both high-level (or logical) and low-level (or physical) design. It allows a user to follow his own preferred methodology rather than restricting him to one specific strategy. SSDE builds and maintains databases that record all design decisions. It provides the system designer with a mechanism whereby systems can easily be modified and new systems can evolve from similar existing systems. There are several auxiliary facilities as productivity aids. SSDE generates PASCAL code for low-level design constructs, ·full documentation of both the high- and low-level designs for inclusion in the project file, as well as a skeleton manual. The system was evaluated by a number of independent users. This exercise clearly demonstrated its success as an aid in expressing, understanding, manipulating and solving software development problems.