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Communications of the ACM

Table of Contents


ACM president's letter: metamorphosis


Controlling the complexity of menu networks

A common approach to the design of user interfaces for computer systems is the menu selection technique. Each menu frame can be considered a node in an information/action network. The set of nodes and the permissible transitions …

Principles of package design

Subprogram packages are groups of related subroutines used to extend the available facilities in a programming system. The results of developing several such packages for various applications are presented, with a distinction …

Authoring systems in computer based education

The idea of a programming system which generates other programs (referred to as automatic programming or metasoftware) has always been a popular one in computer science. Despite the interest, however, few such systems have actually …

On the inevitable intertwining of specification and implementation

Contrary to recent claims that specification should be completed before implementation begins, this paper presents two arguments that the two processes must be intertwined. First, limitations of available implementation technology …

The impact of scanners on employment in supermarkets

A brief review is given of the early estimates of the rate at which scanners would be installed in supermarkets and the resulting labor and consumer responses. The actual situation in 1979 is then discussed and detailed labor …

Programmers use slices when debugging

Computer programmers break apart large programs into smaller coherent pieces. Each of these pieces: functions, subroutines, modules, or abstract datatypes, is usually a contiguous piece of program text. The experiment reported …

Form management

This paper consists of three interrelated parts. In the first part forms are intoduced as an abstraction and generalization of business paper forms. A set of facilities for the manipulation of forms and their contents is outlined …

Searching in a dynamic memory with fast sequential access

This communication presents an algorithm for searching in the Aho-Ullman dynamic memory consisting of (2m - 1) cells. Mean search time of 1.5m steps to the first specified record is obtained with a subsequent sequential access …

Estimating block accesses and number of records in file management

We consider the problems of estimating the number of secondary storage blocks and the number of distinct records accessed when a transaction consisting of possibly duplicate requested records is presented to a file management …

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