John J. Allan

Pragmatic Information Processing Aspects of Graphically Accessed Computer-Aided Design

The specification of the pragmatic information content of graphical displays is approached by defining three display attributes¿ quantity, format, and time. A mathematical measure of pragmatic information quantity is proposed while the effects of format and time on pragmatic information processing activity are discussed qualitatively. An experimental evaluation of the effects of quantity, format, and timing of pragmatic information in a specially constructed graphically oriented design task is described.

Design optimization by adaptive control

Advances in low cost digital computing have spawned new design techniques. One of these, design optimization by adaptive control (DOAC), is explained. The point is made that modeling an entire system to optimize one component has many disadvantages. When using the ideas presented here, a component is removed from a physical system and replaced with a minicomputer, D/A and A/D hardware, transducers, and an adaptive simulation algorithm. An example implementation is given, and some future possibilities are outlined.

Some research advances in computer graphics that will enhance applications to engineering design

Abstract This paper describes some research in man-machine interaction, and graphics hardware-software that will enhance applications to engineering design. Research aspects of CAD executive systems, command languages, and networking are mentioned. Finally, a few areas where little or no research is being done are identified, and consideration is called for.

The effectiveness of direct graphical entry of topological and geometric data

A study is described that was carried out to determine the feasibility of making interactive graphics terminals available for computer-aided instruction (CAI) in engineering and science courses.

The graphically accessed interactive design of industrial pipe systems

For several years the digital computer has been used to aid in the process of designing industrial pipe systems that will be structurally safe under loads imposed by the thermal expansion of the pipe material. Using these programs an analytical approach may be taken when determining stresses and deflections at points throughout pipe systems of great complexity. These analyses are subject only to the constraints of static loading and elastic behavior of the pipe material. Typically, such an analysis procedure is designed for use in batch-processing systems. Programs that have been adapted for use on interactive systems still retain most of the characteristics of the batch processing programs. These programs fail in one important aspect; they require the input/output data for the program to be a string of alphanumeric and special symbols. Quite apart from this convention, piping flexibility analysis problems are invariably presented in a graphical format. Thus, the engineer with a problem to be solved is faced with the time-consuming and potentially error-laden task of expressing the schematic diagram of the proposed pipe system in the alphanumeric input format of the program.

An interactive, interdisciplinary, on-line graphics system for presenting and manipulating directed graphs

An interactive graphics system has been implemented for tutorial purposes and for research in man-machine communication of structural digraphs. An IMLAC intelligent terminal with lightpen input is used in conjunction with a NOVA minicomputer. Successful applications in linguistics and engineering problem solving will be discussed, the latter one in detail.

Planning for an undergraduate level computer-based science education system that will be responsive to society's needs in the 1970's

The purpose of this paper is to discuss the planning of an undergraduate level computer-based educational system for the sciences and engineering that will be responsive to societys needs during the 1970s. Considerable curriculum development research is taking place in many institutions for the purpose of increasing the effectiveness of student learning. Despite the efforts under way, only limited amounts of course matter using computer-based techniques are available within the sciences and engineering.