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This paper presents a routing method for two dimensional transputer arrays particularly designed for parallel non‐linear and dynamic finite element analysis. Some general routing strategies with their strengths and weaknesses are discussed. The need for problem specific routing algorithms in transputer systems is considered and the communication requirements for parallel finite element analysis described. From the communication requirements the design parameters for the routing method are specified and the architectural design of the Router presented. An example of the use of the Router in the parallel non‐linear finite element analysis is given and the robustness of the routing methodology is illustrated by using arbitrary mappings of finite element subdomains distributed over a transputer array.

In recent years attention has turned from conventional ‘von Neumann’ computers to totally new computer architectures. Many surveys of these developments are available and a number of conferences have been held on the topic. One extremely interesting development is the transputer, or so‐called computer on a chip, designed and developed by the British company, Inmos. This exciting innovation has been backed by the SERC, who have launched an initiative entitled ‘Engineering Applications of Transputers’. Under the terms of this initiative, it is possible for British academics to obtain short term loans of transputer equipment, in order to evaluate it and to prepare more extensive research proposals, which would exploit the transputer. The authors obtained a loan of a single transputer board, for 8 months and were able to develop some programs for finite element analysis and for discrete vortex modelling of fluid flows. This paper describes the work carried out on finite elements. The purpose of the paper is to list and describe some simple working finite element programs written in Occam and to draw attention to their novel features.

Systolic array designs of parallel algorithms for low‐level digital image processing, and in particular the gradient operator, are described. Indicates how, to achieve high performance, a new systolic array can be designed in which all the cells in a double pipeline are interconnected to a system bus. The transputer implementation of the design is also considered and comments and conclusions that relate to the use of the systolic array on transputer networks are given. Subsequently it is shown that the systolic array design can be extended to handle the Prewitt and Sobel operators.

A simple discrete vortex program written in the Occam language for implementation on transputers is presented. The programming methodology and logic are described, with an emphasis on the use of parallel features. Listings of procedures discussed in the text are given.

Contract research company Cambridge Consultants is adding biotechnology to its range of sensing interests and is keeping its eye on the transputer. Jack Hollingum went along for an update

This paper describes the development of closed loop control techniques for matrix converter fed induction motor drives. A prototype drive rated at 2.5kW is used to demonstrate closed loop speed control using vector control technique. Solutions to the special problems associated with the power circuit and implementation of closed loop control in the matrix converter drive are given. Experimental results demonstrating the control techniques are presented for both motoring and generating operations of the matrix converter drive in transient and steady‐state.

This paper describes a parallel algorithm for the dynamic relaxation (DR) method. The basic theory of the dynamic relaxation is briefly reviewed to prepare the reader for the parallel implementation of the algorithm. Some fundamental parallel processing schemes have been explored for the implementation of the algorithm. Geometric Parallelism was found suitable for the DR method when using transputer‐based systems. The evolution of the parallel algorithm is given by identifying the steps which may be executed in parallel. The structure of the parallel code is discussed and then described algorithmically. Two geometrically non‐linear parallel finite element analyses have been performed using different mesh densities. The number of processors was varied to investigate algorithm efficiency and speed ups. Using the results obtained it is shown that the computational efficiency increases when the computational load per processor is increased.

This paper describes the simulation of a nearest neighbour searching algorithm for document retrieval using a pool of microprocessors. The documents in a database are organised in a multi‐dimensional binary search tree, and the algorithm identifies the nearest neighbour for a query by a backtracking search of this tree. Three techniques are described which allow parallel searching of the tree. A PASCAL‐based, general purpose simulation system is used to simulate these techniques, using a pool of Transputer‐like microprocessors with three standard document test collections. The degree of speed‐up and processor utilisation obtained is shown to be strongly dependent upon the characteristics of the documents and queries used. The results support the use of pooled microprocessor systems for searching applications in information retrieval.

Presents a review on implementing finite element methods on supercomputers, workstations and PCs and gives main trends in hardware and software developments. An appendix included at the end of the paper presents a bibliography on the subjects retrospectively to 1985 and approximately 1,100 references are listed.

In Part I of this article, surveys of the architectural concepts involved in designing special‐purpose VLSI computing structures are given. This leads to a discussion of systolic array, wavefront array, WARP and CHiP architectures and their applications. The INMOS transputer chip design and the parallel language OCCAM are introduced. The authors believe that together they form a modular hardware/software component of the type which is essential in the construction of highly parallel computer systems. (Part II of this article will consider the soft simulation of systolic algorithms via OCCAM and the systolisaion of the pattern matching problem).