Daniel Teichroew

PSL/PSA: A Computer-Aided Technique for Structured Documentation and Analysis of Information Processing Systems

PSL/PSA is a computer-aided structured documentation and analysis technique that was developed for, and is being used for, analysis and documentation of requirements and preparation of functional specifications for information processing systems. The present status of requirements definition is outlined as the basis for describing the problem which PSL/PSA is intended to solve. The basic concepts of the Problem Statement Language are introduced and the content and use of a number of standard reports that can be produced by the Problem Statement Analyzer are briefly described.

Computer simulation—discussion of the technique and comparison of languages

The purpose of this paper is to present a comparison of some computer simulation languages and of some of the packages by which each is implemented. Some considerations involved in comparing software packages for digital computers are discussed in Part I. The issue is obvious: users of digital computers must choose from available languages or write their own. Substantial costs can occur, particularly in training, implementation and computer time if an inappropriate language is chosen. More and more computer simulation languages are being developed: comparisons and evaluations of existing languages are useful for designers and implementers as well as users. The second part is devoted to computer simulation and simulation languages. The computational characteristics of simulation are discussed with special attention being paid to a distinction between continuous and discrete change models. Part III presents a detailed comparison of six simulation languages and packages: SIMSCRIPT, CLP, CSL, GASP, GPSS and SOL. The characteristics of each are summarized in a series of tables. The implications of this analysis for designers of languages, for users, and for implementers are developed. The conclusion of the paper is that the packages now available for computer simulation offer features which none of the more general-purpose packages do and that analysis of strengths and weaknesses of each suggests ways in which both current and future simulation languages and packages can be improved.

Education related to the use of computers in organizations

The ACM Curriculum Committee on Computer Education for Management has been carrying out a study on “Curriculum Development in Management Information Systems Education in Colleges and Universities” under a grant from the National Science Foundation. This position paper provides a framework for the study. Preliminary conclusions are presented on the need for education in administrative information systems, and appropriate college curricula and courses are suggested. Also, the role of professional societies and organizations using computers is discussed, and the plans of the Committee are outlined. The initial approach of the Committee has been to describe the education necessary for the effective use of computers in organizations, to classify the positions for which education is required, and to survey educational programs now available.

A survey of languages for stating requirements for computer-based information systems

Society depends more and more on the recording, analysis, storage, processing, and transmission of data and information. Practically every activity requires an information system. The larger and more organized the activity, the larger and more organized is the information system which serves it. This paper is concerned with Information Processing Systems (IPS) which are built to aid the management and operation of an organization. In particular, the paper is concerned with the methods by which the information needs of the organization can be communicated effectively to those who are asked to implement systems to satisfy the requirements for planning, control, and operations.

Developing manufacturing control software: a survey and critique

The complexity and diversity of manufacturing software and the need to adapt this software to the frequent changes in the production requirements necessitate the use of a systematic approach to developing this software. The software life-cycle model (Royce, 1970) that consists of specifying the requirements of a software system, designing, implementing, testing, and evolving this software can be followed when developing large portions of manufacturing software. However, the presence of hardware devices in these systems and the high costs of acquiring and operating hardware devices further complicate the manufacturing software development process and require that the functionality of this software be extended to incorporate simulation and prototyping.This paper reviews recent methods for planning, scheduling, simulating, and monitoring the operation of manufacturing systems. A synopsis of the approaches to designing and implementing the real-time control software of these systems is presented. It is concluded that current methodologies support, in a very restricted sense, these planning, scheduling, and monitoring activities, and that enhanced performance can be achieved via an integrated approach.

Mining protein data from two-dimensional gels: tools for systematic post-planned analyses.

There is a considerable need to develop comprehensive, systematic mechanisms to analyze the vast number of proteins that orchestrate various cellular functions and to identify proteins associated with disease or that are affected by pharmacological agents. Two‐dimensional polyacrylamide gel electrophoresis (2‐D PAGE) continues to be relied upon to analyze protein constituents of cells and tissues. We have developed a Laboratory Information Processing System (LIPS) as a computer‐based tool for capturing quantitative and qualitative changes in thousands of proteins detected in 2‐D gels of various types. Protein databases have been developed to serve as a repository for data processing of the basic and derived data and of findings derived from different studies. There have been remarkable advances both in database technology as well as in the computer hardware that have benefited our effort at mining protein data from 2‐D gels. We here review our current efforts aimed at improving the performance and features of our 2‐D related protein databases, with particular emphasis on the tools we utilize for database mining via a systematic analysis of information known as post‐planned analysis.

Real-time software methodologies: are they suitable for developing manufacturing control software?

Computer-Integrated Manufacturing (CIM) systems may be classified as real-time systems. Hence, the applicability of methodologies that are developed for specifying, designing, implementing, testing, and evolving real-time software is investigated in this article.The paper highlights the activities of the software development process. Among these activities, a great emphasis is placed on automating the software requirements specification activity, and a set of formal models and languages for specifying these requirements is presented. Moreover, a synopsis of the real-time software methodologies that have been implemented by the academic and industrial communities is presented together with a critique of the strengths and weaknesses of these methodologies.The possible use of the real-time methodologies in developing the control software of efficient and dependable manufacturing systems is explored. In these systems, efficiency is achieved by increasing the level of concurrency of the operations of a plan, and by scheduling the execution of these operations with the intent of maximizing the utilization of the devices of their systems. On the other hand, dependability requires monitoring the operations of these systems. This monitoring activity facilitates the detection of faults that may occur when executing the scheduled operations of a plan, recovering from these faults, and, whenever feasible, resuming the original schedule of the system.The paper concludes that the set of surveyed methodologies may be used to develop the real-time control software of efficient and dependable manufacturing systems. However, an integrated approach to planning, scheduling, and monitoring the operations of these systems will significantly enhance their utility, and no such approach is supported by any of these methodologies.

Research needs and challenges in application of computer and information sciences for industrial engineering

Abstract By invitation from the Editor of IIE Transactions, a research forum was established in 1987 to develop and prepare this article. The objective: to write on the directions, needs and challenges for research by the IE com-munity in applying computer and information sciences. The motivation: realizing the major advancements in computer and information sciences in the recent decade and their significant impact on the IE profession, it is vital to examine how IE research activities can respond effectively to current and emerging needs. This article is viewed as a useful contribution to such an examination. Forum members were invited from academia, government and industry based on their experience in and commitment to research in this area. The forum was chaired by Shimon Y. Nof and the members are the co-authors of this article. Forum members communicated and deliberated throughout 1987 and met for a review and planning session dur-ing the IIE Conference in Washington, D.C. in May, 1987 (Forum, 1987)....

A computer-aided technique for structured documentation

PSL/PSA--which stands for Problem Statement Language/Problem Statement Analyzer--is a tool for describing information processing systems and recording such descriptions in machine-processable form. The manual method for definition of requirements or specifications for a proposed information processing system used in most organizations consists of a number of different activities. Analysts collect data about the present system and about requirements for the new system from various sources in various ways, such as interviews. This data is then collated, analyzed and summarized. The end result is a set of specifications for a new system. These speci f icat ions are usual ly included, together with an implementation plan and benefit cost analysis, in a final document which has different names in different organizations: feasibility report, system definition report, system specification report, functional requirements report and so on. PSL/PSA supplements the manual procedures by providing the capability to use the computer for some of the clerical activities. The data is still collected from the usual sources by the analysts. As it is collected, however, it is expressed in a formal language called the Problem Statement Language (PSL). (The name derives from the fact that the analysts are expressing a problem to be solved by the system implementors.) The data expressed in PSL is entered into a computerized data base incrementally as it is obtained, or in batches as desired. As it is entered, the Problem

Pragmatic issues in conversions of database applications

The need to convert database applications from one DBMS to another arises frequently. This paper presents a cost/benefit evaluation model for the database conversion problem, applies this model to several situations involving convertion of large database applications and proposes a decision support system for database conversion decisions. It also points out that although most of the literature focuses on database models and structures, in practice organizational and human considerations play a key role in the conversion of database applications and may become a limit to the growth of new database applications.