NEXUS: towards a problem solving environment (PSE) for scientific computing

ABSTRACT

This paper gives a brief historical perspective on the first author's use of information systems in mathematical consulting. Experience in this area has led to the conclusion that numerical analysts must look beyond conventional expert systems if they are to be successful in reaching the general scientific user community. With the increasing use of personal workstations it is necessary to give information and advice to a user while at the computer terminal. In the opinion of the authors the ideal way of doing this is through a programming environment that offers interaction with a user in order to actually solve the user's problem.Such an environment has come to be called a Problem Solving Environment or PSE. (For an excellent discussion of PSEs see Ford and Iles, 1985.) This paper describes a project that is aimed at providing a PSE for scientific computing. The project, which is called NEXUS, can be viewed conveniently in two parts, namely, the development of a set of software modules for constructing and accessing information in a knowledge base and the production of a set of knowledge bases for a particular application area namely, mathematical software.The paper briefly describes the set of modules and knowledge bases that are under development for the first release of NEXUS. For a more complete description the reader is referred to the companion report by Gaffney et al., (1986a).

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INDEX TERMS

Keywords:
concurrent analysis, expert systems, information search and retrieval-selection process, intelligent front-ends, knowledge-based systems, man-machine interaction, on-line information services, parallel computing, problem solving environments, user/machine systems