Future applications of associative processor systems to operational KSC systems for optimizing cost and enhancing performance characteristics

The application of associative memory processor equipment to conventional host processors type systems is discussed. Efforts were made to demonstrate how such application relieves the task burden of conventional systems, and enhance system speed and efficiency. Data cover comparative theoretical performance analysis, demonstration of expanded growth capabilities, and demonstrations of actual hardware in simulated environment

Investigate and classify various types of computer architecture

Issued as Final report, Project no. G-36-60

The simulation of fluid flow processes using vector processors

In this thesis the potential gains in vectorisation of linear and non-linear systems of equations are investigated. Previous studies carried out on the suitability of algorithms for vectorisation have been based on the solution of Poisson's equation. In accordance with this, a range of algorithms are explored and compared using a VA-1 pipeline processor attached to a MASSCOMP MC5400. Analysis shows that almost full vectorisation is possible leading to speed-up factors of up to 90. Based on these results the vectorised conjugate gradient with a Jacobi preconditioner (JCGV) is the best of the algorithms considered. This work is extended to the development of a two-dimensional fluid flow code which is used to solve the Navier-Stokes equations, SIMPLE is implemented to handle the non-linear nature of the equations. The first two problems are isothermal flows, viz, the 'moving lid cavity' and the 'sudden expansion in a duct' problem. A study of where the greatest computational effort is expended, and subsequent vectorisation leads to 98% of SIMPLE being modified. This results in speed-up factors of 6 for the cavity problem and 29 for the sudden expansion problem. In both problems the JCGV is marginally faster than the vectorised Jacobi with under-relaxation (JURY). However, the JCGV algorithm is not robust and it is necessary to relax carefully the approximation, otherwise high computation times or divergence is likely. Two further problems are considered each with increasing complexity, these include scalar quantities of temperature and characteristics of k-e turbulence. One problem is based on 'turbulent L-shaped flow in a duct' and the other on the 'natural convection in a square cavity'. A consequence of the higher scalar computation gives speed-up factors of 5 for the turbulent L-shaped flow and 11 for the natural convection problem. There is little to choose between the JCGV and JURV algorithms, however, the robustness problems with the JCGV algorithm remain. A multigrid method (ACM) is used to improve the convergence rate of the algorithms, particularly as the size of problem is increased. Although it is more effective in scalar, it also provides worthwhile improvements for the vectorised algorithms with overall factors of 8.5. Convergence difficulties with the JCG algorithm also prevents the combination with the ACM method. Therefore, the vectorised JUR algorithm with the ACM method is not only more efficient and reliable, but also has scope for improvement as the grid is increased. The potential gains in vectorisation of the SIMPLE family on pipeline architectures have been clearly demonstrated and indicate that such efforts on practical CFD codes should be well rewarded with regard to processor performance

Solution of partial differential equations on vector and parallel computers

The present status of numerical methods for partial differential equations on vector and parallel computers was reviewed. The relevant aspects of these computers are discussed and a brief review of their development is included, with particular attention paid to those characteristics that influence algorithm selection. Both direct and iterative methods are given for elliptic equations as well as explicit and implicit methods for initial boundary value problems. The intent is to point out attractive methods as well as areas where this class of computer architecture cannot be fully utilized because of either hardware restrictions or the lack of adequate algorithms. Application areas utilizing these computers are briefly discussed

Briefing Materials for Technical Presentations, Volume A: The LACIE Symposium

Tables, charts, and outlines of various segments within the Large Area Crop Inventory Experiment are presented. Experiment design, system implementation and operations, and data processing system design were considered

Aeronautical Engineering. A continuing bibliography, supplement 115

This bibliography lists 273 reports, articles, and other documents introduced into the NASA scientific and technical information system in October 1979

Network control for a multi-user transputer-based system.

A dissertation submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in EngineeringThe MC2/64 system is a configureable multi-user transputer- based system which was designed using a modular approach. The MC2/64 consists of MC2 Clusters which are connected using a modified Clos network. The MC2 Clusters were designed and realised as completely configurable modules using and extending an algorithm based on Eulerian cycles through a requested graph. This dissertation discusses the configuration algorithm and the extensions made to the algorithm for the MC2 Clusters. The total MC2/64 system is not completely configurable as a MC2 Cluster releases only a limited number of links for inter-cluster connections. This dissertation analyses the configurability of MC2/64, but also presents algorithms which enhance the usability of the system from the user's point of view. The design and the implementation of the network control software are also submitted as topics in this dissertation. The network control software must allow multiple users to use the system, but without them influencing each other's transputer domains. This dissertation therefore seeks to give an overview of network control problems and the solutions implemented in current MC2/64 systems. The results of the research done for this dissertation will hopefully aid in the design of future MC2 systems which will provide South Africa with much needed, low cost, high performance computing power.Andrew Chakane 201

Concurrent Probabilistic Simulation of High Temperature Composite Structural Response

A computational structural/material analysis and design tool which would meet industry's future demand for expedience and reduced cost is presented. This unique software 'GENOA' is dedicated to parallel and high speed analysis to perform probabilistic evaluation of high temperature composite response of aerospace systems. The development is based on detailed integration and modification of diverse fields of specialized analysis techniques and mathematical models to combine their latest innovative capabilities into a commercially viable software package. The technique is specifically designed to exploit the availability of processors to perform computationally intense probabilistic analysis assessing uncertainties in structural reliability analysis and composite micromechanics. The primary objectives which were achieved in performing the development were: (1) Utilization of the power of parallel processing and static/dynamic load balancing optimization to make the complex simulation of structure, material and processing of high temperature composite affordable; (2) Computational integration and synchronization of probabilistic mathematics, structural/material mechanics and parallel computing; (3) Implementation of an innovative multi-level domain decomposition technique to identify the inherent parallelism, and increasing convergence rates through high- and low-level processor assignment; (4) Creating the framework for Portable Paralleled architecture for the machine independent Multi Instruction Multi Data, (MIMD), Single Instruction Multi Data (SIMD), hybrid and distributed workstation type of computers; and (5) Market evaluation. The results of Phase-2 effort provides a good basis for continuation and warrants Phase-3 government, and industry partnership