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Research and Advances

A comparison of disks and tapes

The principal characteristics of current magnetic disks and tape units are summarized and compared. Some of the characteristics of disk files are illustrated in a sorting example and compared to a tapesort. The conclusion is presented that disk files are competitive to tapes in some important applications.
Research and Advances

DATA-DIAL: two-way communication with computers from ordinary dial telphones

An operating system is described which allows users to call up a remotely located computer from ordinary dial telephones. No special hardware or connections are required at the users' telephones. Input to the computer is through the telephone dial; output from the computer is in spoken form. Results of a test with telephones in the Boston area are reported.
Research and Advances

Variable width stacks

Character addressable, variable field computers permit ready establishment and manipulation of variable width stacks. Single machine commands may push variable field items down into such stacks or pop them up. The availability of a variety of field delimiters allows the machine to push down or pop up more than one variable width item with one command. Since these stacking operations can be made the basis of compiler decoding algorithms, the proper use of machines of this class for compilation has advantages over machines with fixed-length words.
Research and Advances

What is proprietary in mathematical programming?— impressions of a panel discussion

A panel discussion on “What is Proprietary in Mathematical Programming?” was sponsored by the Special Interest Committee on Mathematical Programming of the ACM during a Hall of Discussion/on September 7th at the 16TH National ACM meeting in Los Angeles. This note consists solely of the impressions garnered by the moderator of the panel and does not necessarily represent the position of any of the panelists or other participants in the discussion.
Research and Advances

n-dimensional codes for detecting and correcting multiple errors0

The paper introduces a new family of codes for detecting and correcting multiple errors in a binary-coded message. The message itself is arranged (conceptually) into a multidimensional rectangular array. The processes of encoding and error detection are based upon parity evaluations along prescribed dimensions of the array. Effectiveness of the codes is increased by introducing a “system check bit”, which is essentially a parity check on the other parity bits. Only three-dimensional codes are discussed in this paper, with parity evaluations along the horizontal, the vertical, and one main diagonal. However, the family of codes is not restricted to three dimensions, as evidenced by the discussion by Minnick and Ashenhurst on a similar multidimensional single-bit selection plan used for another purpose [6]. A four-dimensional code, correcting three and detecting four errors, has been developed; the extension to higher-dimensional codes with greater correction power is straightforward.
Research and Advances

A semi-automatic storage allocation system at loading time

The method of storage allocation described herein, although new in a few respects, does not represent any sharp break from the past. Rather it is another step of development suggested by experience accumulated over several years with the 704,709 and 7090 FORTRAN systems. The storage assignment method proposed is, in principle, extremely simple and is not specific to FORTRAN or the 7090. Although the method depends only on rather general language aspects, the concrete detail will be illustrated in terms of the aforementioned systems or proposed extensions.
Research and Advances

A storage allocation scheme for ALGOL 60

A storage allocation scheme for a machine with a 2048-instruction core store and a magnetic drum is described. The use of the drum for storing program blocks and/or data must be directed by the programmer through auxiliary information in the ALGOL program. The administrative routines controlling the storage at run time are described in full. A detailed example is given.
Opinion

The international impact of computers

Just one year ago, I had the pleasure of surveying over 40 laboratories, factories and universities throughout Western Europe that were actively engaged in the computer field. Since then, many visitors from Europe have visited me and updated my information on the status of developments abroad.
Research and Advances

A preplanned approach to a storage allocating compiler

The preplanned approach to the storage allocation problem involves using a fixed method of analysis of a problem to produce an efficient computer program incorporating all necessary transfers of information within the multilevels of storage of the computer throughout the running of the object program. The initial description of the problem may be in any suitable source language (FORTRAN, ALGOL, etc.) but should not require any recognition of the limitations caused by the number, size, and speeds of the computer's storage devices (core, tape, disc, number of data channels, etc.) by the programmer. The object program produced should contain all necessary implementing instructions to utilize all of the computer's storage devices in such a manner as to minimize the cost of the program (i.e. maximize the speed of problem solving).

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