摘要:

Integrated project support environments (IPSEs) are intended to provide a cohesive and integrated set of tools to support the process of design and development in software engineering projects. Much current research is concentrated on maximising the degree to which these tools can be integrated. This paper briefly describes the architecture of a prototype IPSE which attempts to achieve a high degree of integration using techniques drawn from the disciplines of intelligent knowledge-based systems, office automation and object-oriented programming. The remainder of the paper deals with the design of a user interface to the IPSE based on direct manipulation. It argues that this provides a consistent and integrated method with which users can interact with the objects in the IPSE's object store.

DOI:10.1049/sej.1988.0027

出版商:IEE    

年代:1988

数据来源: IET

摘要:

As maintenance costs continue to increase at an alarming pace, improved techniques for controlling the maintenance process become imperative. The need to seek methods, applied throughout the development process, that address the maintainability of software has never been greater. One approach to improving the maintainability of software is to control the complexity of the module at the design phase. Since complexity is a measure of the effort to comprehend and maintain software, maintenance effort increases as complexity increases. This study provides an analysis of the changes in complexity during the development of two systems based on different development paradigms. Inter-system and intra-system comparisons of complexity increases are performed. Six complexity metrics representing structure, length and composite characteristics are evaluated. Results of the study include variances in complexity increases between systems based on different development paradigms.

DOI:10.1049/sej.1988.0028

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Symbolic execution is a technique that is useful in the validation of software. It may be used to aid in the generation of test data and in program proving. As software engineering becomes more concerned with the development of tools, symbolic execution will become an important item in the toolkit. This paper gives a review of symbolic execution and its applications. A minimum set of features for a symbolic execution testing system is set out. Of the 12 systems using symbolic execution only six contain these minimum features. These six systems are compared against an ‘ideal’ system. Based on this comparison some features for a new symbolic execution testing system are outlined.

DOI:10.1049/sej.1988.0029

出版商:IEE    

年代:1988

数据来源: IET

摘要:

This paper describes a space-efficient technique for recording successive differences between versions of data. The technique is based on the combined use of differential files and change area b-trees. The strengths of the technique are that a branching tree of versions can be accommodated; any data item in any version can be accessed with approximately equal access time; and very large volumes of data can be accommodated. The paper also describes the use of this technique to support very long transactions in the SDS2 software development system. Here the technique is used in an optimistic concurrency control scheme.

DOI:10.1049/sej.1988.0030

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Computer graphics systems have traditionally been described in terms of a conceptual model of the so-called ‘graphics processing pipeline’. This model explains the relationship between graphics information defined by an application and the realisation of that information on a display in terms of a sequence of transformation stages. Although adequate for giving an outline of a single graphics system, the model lacks flexibility and detail when placed in the sphere of many different graphics systems designs, as in the ‘family of graphics systems’ under ISO standardisation at the current time. An alternative approach is needed which provides a sufficient level of detail and flexibility to describe both existing graphics systems and possible extensions to these, which at the same time permits the comparison of graphics systems designs in a well defined framework. The computer graphics reference model presented in this paper meets many of these objectives.

DOI:10.1049/sej.1988.0032

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Nowhere in software engineering is the need for fast prototyping more widely accepted than in the design of effective user interfaces to interactive systems. This paper reviews the rationale and methods for prototyping of interfaces, and argues the importance of dynamic reconfigurability in achieving fast convergence on a satisfactory solution. A prototype dialogue design system with this property is described, and the results of initial experience in its use are reported.

DOI:10.1049/sej.1988.0033

出版商:IEE    

年代:1988

数据来源: IET

摘要:

Much attention has been paid recently to graphics packages which provide standard mechanisms for graphical output in a device-independent way. These packages usually attempt to model a repertoire of input tools in a similarly abstract way. While implementing the Graphical Kernel System (GKS) it was observed that the model for handling interactive input was unnecessarily complicated; an alternative scheme was, therefore, designed and implemented offering considerable generality and device independence. This approach is based on the use of a command interpreter driven by a character stream multiplexing the data from the various input tools attached to a terminal. This implementation has proved portable between several different terminals using disparate input devices. A further result was the development of a terminal emulation program for a simple microcomputer, which works with the software described to provide many of the facilities normally associated with high-performance workstations.

DOI:10.1049/sej.1988.0034

出版商:IEE    

年代:1988

数据来源: IET