Techniques for improving reliability of computers

Modular design techniques improve methods of error detection, diagnosis, and recovery. Theoretical computer (MARCS (Modular Architecture for Reliable Computer Systems)) study deals with postulated and modeled technology indigenous to 1975-1980. Study developments are discussed

Self testing and repairing computer - A concept

STAR computer has five redundant modular function units, fixed store, arithmetic, memory, input, and output. Each unit is connected to a diagnostic control unit, each is coded for error detection and error correction. Separation into function units permits assembly of many different systems from the set of units

Finite element analysis in a minicomputer/mainframe environment

Design considerations were evaluated for general purpose finite element systems to maximize performance when installed on distributed computer hardware/software systems. It is shown how the features of current minicomputers complement those of a modular implementation of the finite element method for increasing the control, speed, and visibility (interactive graphics) in solving structural problems at reduced cost. The approach used is to implement a finite element system in a distributed computer environment to solve structural problems and to explore alternatives in distributing finite element computations

Comparison between two VSC-HVDC transmission systems technologies : modular and neutral point clamped multilevel converter

The paper presents a detail comparison between two voltage source converter high voltage dc transmission systems, the first is based on neutral point-clamped (also known as HVDC-Light) and the second is based on innovative modular multilevel converter (known as HVDC-Plus). The comparison focuses on the reliability issues of both technologies such as fault ride-through capability and control flexibility. To address these issues, neutral point-clamped and three-level modular converters are considered in both stations of the dc transmission system, and several operating conditions are considered, including, symmetrical and asymmetrical faults. Computer simulation in Matlab-Simulink environment has been used to confirm the validity of the results

Distributed modular RT-systems for detector DAQ, trigger and control applications

A modular approach to development of distributed modular system architecture for detector control, data acquisition and trigger data processing is proposed. A multilevel parallel-pipeline model of data acquisition, processing and control is proposed and discussed. Multiprocessor architecture with SCI-based interconnections is proposed as good high-performance system for parallel-pipeline data processing. A network (Ethernet -100) can be used for loading, monitoring and diagnostic purposes independent of basic interconnections. The modular cPCI-based structures with high speed modular interconnections are proposed for DAQ and control applications. For distributed control RT-systems, to construct the effective (cost-performance) systems the same platform of an Intel compatible processor board should be used. The basic computer multiprocessor nodes consist of high-power PC MB (Industrial Computer Systems), which are interconnected by SCI modules and link to embedded microprocessor-based sub-systems for control applications. The required number of multiprocessor nodes should be interconnected by SCI for parallel-pipeline data processing in real time (according to the multilevel model) and link to RT-systems for embedded control. (19 refs)

Macaulay inverse systems revisited

Since its original publication in 1916 under the title "The Algebraic Theory of Modular Systems", the book by F. S. Macaulay has attracted a lot of scientists with a view towards pure mathematics (D. Eisenbud,...) or applications to control theory (U. Oberst,...).However, a carefull examination of the quotations clearly shows that people have hardly been looking at the last chapter dealing with the so-called "inverse systems", unless in very particular situations. The purpose of this paper is to provide for the first time the full explanation of this chapter within the framework of the formal theory of systems of partial differential equations (Spencer operator on sections, involution,...) and its algebraic counterpart now called "algebraic analysis" (commutative and homological algebra, differential modules,...). Many explicit examples are fully treated and hints are given towards the way to work out computer algebra packages.Comment: From a lecture at the International Conference : Application of Computer Algebra (ACA 2008) july 2008, RISC, LINZ, AUSTRI

Software handlers for process interfaces

Process interfaces are developed in an effort to reduce the time, effort, and money required to install computer systems. Probably the chief obstacle to the achievement of these goals lies in the problem of developing software handlers having the same degree of generality and modularity as the hardware. The problem of combining the advantages of modular instrumentation with those of modern multitask operating systems has not been completely solved, but there are a number of promising developments. The essential principles involved are considered