Showing papers on "Application software published in 1970"

Techniques for the Real-Time Monitoring of Power System Operations

Abstract: This paper describes methods for using power system readings to compute a real-time power flow solution of the transmission network. The use of redundant data is discussed and procedures are outlined to detect, identify, and correct for data errors. Several examples are presented and the numerical behavior of the methods is discussed.

A real-time language for industrial process control

Abstract: Industrial computer control systems require the economical production of efficient software including executive systems, maintenance programs, and both special and general purpose application programs for direct digital control. Moreover, the hardware configuration varies considerably from the single dedicated control computer to a general purpose multicomputer system. RTL, a real-time language developed cooperatively with industrial suppliers and users specifically for industrial control, is described with emphasis on those features peculiar to applications such as dedicated direct digital control, combined direct and supervisory control, operator interfaces, and interaction with plant management computer systems. The use of RTL for the production of special purpose executive systems and general purpose application programs for direct control, startup, etc., is emphasized. Details of the language discussed with examples include its file structure for communication of data bases between independent programs, and a variety of data types including character codes, strings, labels, lists, peripheral variables, and data structures. Peripheral variables are variables in the language associated with hard-ware features of the central processor and its input-output devices such as registers, interrupts, error indicators, and addresses all of which may be referenced in the language. Regular and peripheral variable data structures--combinations of different types of variables--are included and ease considerably the burden of real-time programming. The organization and performance of the existing compiler for RTL is explained.

Laboratory computers: Their capabilities and how to make them work for you

Abstract: A laboratory computer is a small- or medium-sized general-purpose machine which has been specially selected to do a particular job. Important economies as well as great computing power are achievable by matching not only the kind of machine, but also the particular set of components to the tasks at hand. For this reason, laboratory computers have become very popular. In addition to selecting the hardware, advantages can be achieved by tailoring the operating system and other general software to the situation. Enough operating systems for such computers have now been written to show how a specific system may be developed by modifying and incorporating features of existing systems and by modifying standard Programs supplied by computer manufacturers. In this way, special systems can be implemented using a reasonable amount of time and effort. This paper provides an introduction to laboratory computer operating systems to serve as a starting point for someone intending to create his own system. Specific systems for a LINC computer, and for the Honeywell DDP-224 and DDP-516 computers are described in some detail. These systems illustrate many features that have been found useful. The documentation needed to use the computer, the size of the user group, and some of the history of development are mentioned. Similar systems can be created to focus new machines on new tasks. Only current state-of-the-art programming is needed. The benefits of such specialization far outweigh the effort and costs.

Computer Architecture for Process Control

Abstract: In recent years the Process Control Industry has opened new avenues for the application of digital computers. Processing capability of third generation machines makes it possible to apply these computers to a large number of control applications. The vast differences in magnitude between process variable time constants and computer processing rates has allowed the digital computer to enter an area previously reserved for the analog computer.