Use Of Computer-aided Research Articles

State of the art of use of computer aids for decision-making in control centres

In 1978, the Large Systems and International Interconnections Study Committee of Unipede requested the ‘Future Load Control Centre’ Group of Experts to investigate, with Unipede member countries, present practice in, and future prospects for, the use of computer aids in decision-making at European control centres. For this purpose, a questionaire was sent, in 1978, to the companies represented in the Group of Experts so as to obtain a wider range of replies. The report is based on 26 replies from 13 countries, received before 1 December 1979.

SAT Revisited — A Critical Post-Examination of the Systems Approach to Training

A unique application of the Systems Approach to Training (SAT) was carried out for the design of the B-1 aircrew instructional system. A preliminary report was presented at the 1975 Human Factors Society Meeting by Johnson, et aI, (1974) and Sugarman, et aI, (1974). Based on the additional experience, this presentation will share with the training community a look at some of the strengths and weaknesses of the SAT process. The particular application provided a harsh test of the process since the B-1 air vehicle is still in the developmental stages. This resulted in many opportunities to be faced with missing or incomplete data whose criticality to the analysis became more than apparent. The genral state-of-knowledge within Instructional System Development (ISD) itself is incomplete, which also became apparent when applying a highly structured (i.e., internally consistent and documented) SAT process. The major strength of the SAT process is the capability it provides for the justification of many decisions that were hitherto prone to hand-waving. This particular strength comes from the internal documentation for each decision process which is an important feature of SAT. The adequacy of the assumptions underlying the decision processes then becomes subject to scrutiny. The power of the documentation is enhanced by the use of computer aids in data management and economic analysis which facilitate the documentation. Within the present paper, problem areas which weaken the SAT process are also discussed. These include the data bases for the task analysis and economic/policy data, the media selection process, and the development of instructional strategies.

IEE Electronics Division: Chairman's address. Computer-aided design in electronics

The address reviews the development of computer-aided design (c.a.d.) in the last few years. In a historical introduction, the main characteristics of c.a.d. are outlined, particularly the use of interactive computing with time-sharing teletype keyboards or with c.r.t. graphics. The main applications to electronics are then reviewed, including device modelling, circuit analysis, network optimisation, logic simulation and general computing for local needs. The design of integrated circuits and their extensive use of computer aids are treated in more detail. Some less well established topics are then briefly touched on, particularly the possibilities of automatic layout of integrated and printed circuits and c.a.d. methods for large-systems design. The address continues with a section on equipment and software for c.a.d. and typical costs. It concludes with some comments on the present usefulness and limitations of c.a.d. and on trends for the immediate future. Batch processing will occupy a continuing role for large-scale calculations. The time-sharing teletype terminal is the most useful and flexible link to the computer for most applications. Interactive graphic displays are useful for layout tasks, but are still complex and expensive.

A Cost Optimized, Heatsinkless RGB Amplifier

Are heatsinks really needed in the red-green-blue video amplifier? Their cost is appreciable. In large-volume consumer production, engineering effort to eliminate heatsinks is well worthwhile. This effort may make use of computer aid. In particular, computer programs having statistical analysis routines may be applied to power dissipation levels, thus providing greater information about transistor junction temperatures.

A computer algorithm for state table reduction

As part of a large research programme on the use of computer aids for logic circuit design, it was required to provide an algorithm for the reduction of sequential circuit state tables (completely or incompletely specified). This paper discusses the theoretical problems of state reduction and demonstrates how a rapid solution may be obtained based on the determination and use of a closure function associated with each maximal or prime compatible set. The use of several heuristics ensures that a near-minimal solution to the subsequent closed-cover problem is always obtained, rather than the absolute minimum that is theoretically possible but computationally impracticable. This is in keeping with the overall design philosophy of producing a viable engineering design rather than the theoretical optimum usually dictated by switching theory. The algorithm has been programmed and the paper further discusses the data structures used and problems encountered in its implementation.

Statistical Circuit Design: A Case Study of the Use of Computer Aids in Circuit Design-Pulse Equalizers for the T2 Digital Transmission Line

Computer simulation makes it economically feasible to analyze competing circuit configurations and optimize the circuit parameters using complicated criteria related to system performance. Furthermore, the influence of manufacturing tolerances on optimized performance can be statistically investigated to establish component specifications before production is started. Thus, the designer can predict more easily whether or not a circuit will perform adequately in the field. In addition, computer operated test sets can provide accurate measurements of circuit performance during manufacture to insure that the product will be satisfactory. These test facilities can be programmed to provide a factory evaluation of the individual circuits based on worst-case system performance. To illustrate these concepts, it is shown how computer aids were utilized in the design of the pulse equalizers for the T2 digital transmission line. The discussion of the equalizer design is intended to illustrate why and in what manner the various functions were implemented. The statistical tolerance analysis and manufacturing test phases receive the greatest emphasis as they are the most recent developments.

Methods of extracting radar data for automatic processing

Two alternative approaches to the problem of converting radar signals into a form suitable for use in digital computers are considered and the problems discussed. One is automatic extraction and track production, and the other is manual, but based on the use of computer aids to enhance the operator's efficiency and reliability. Possible solutions are outlined and some difficulties which need to be overcome are explained.The two methods are then compared from the point of view of a potential user and it is shown that, when reasonably developed, each method has advantages. The relative advantages of the two approaches show up differently under different requirements and the choice must therefore be made in the light of a particular set of present and future requirements.It is also suggested that the choice is not always clear-cut. Automatic tracking systems may need human assistance in some circumstances and manual systems may be successively more assisted by a computer.