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The paper describes a scheme for symbolic manipulation of index expressions which arise as a by-product of the symbolic manipulation of expressions in the matrix calculi described by the authors in a previous paper. This scheme attempts program optimization by transforming the original algorithm rather than the machine code. The goal is to automatically generate code for handling the tedious address calculations necessitated by complicated data structures. The paper is therefore preoccupied with "indexing by position." The relationship of "indexing by name" and "indexing by position" is discussed. [ABSTRACT FROM AUTHOR]

Multiprogramming as it is discussed here is a mode of computer operation in which two or more programs are concurrently in processor memory and proceeding, each using the same central processor unit (CPU) and input-output (I/O) channels. These programs are actually proceeding intermittently and singly, according to eligibility (readiness to proceed) and priority. It is useful to be able to represent them as proceeding continuously and simultaneously, each at an effective rate, which may be a fraction of that which it would enjoy in the absence of the other programs. The effective progress rate of each program is sensitive to many detailed characteristics of itself and its co-residents; and simulation has been the best available method of predicting it. This paper presents the results of progress in developing an alternative to simulation, a simulation-tested iterative computation of these rates under certain situations. The algorithm is sensitive to most of the factors that control the phenomenon, including nonquantitative or topological features of the programs' structures. [ABSTRACT FROM AUTHOR]

This paper is concerned with a review and examination of several existing algorithms for the zero-one programming problem. Computational experience is summarized. The machine time and storage requirements of several of the algorithms are compared over several test problems of small and intermediate size. Computer experiments still provide little hope of solving problems with over 100 variables with a reasonable amount of machine time. [ABSTRACT FROM AUTHOR]

High-priority paralysis is the degradation that can occur in multiprogramming systems when scheduling is based primarily on preassigned priorities. It can be alleviated by modifying the scheduling algorithm to maximize the number of programs active at one time. The case history given in this paper indicates two general methods by which simultaneity can be increased. Possible refinements in the scheduling algorithm for future improvements are considered briefly. [ABSTRACT FROM AUTHOR]

The article focuses on a paper indicating the error of algorithmic language ALGOL 60 pointed up by the Algorithm 355 construct in the October 1969 issue of the periodical "Communications of the Automation for Computing Machinery." The procedure statement "p" occurs in the body of this procedure, showing "p" to be a procedure without parameters. As originally submitted, the algorithm contained several procedure statements in which p was replaced by a procedure statement. It is possible that the authors of ALGOL 60 intended to permit this but they did not do so. The author's original form may have been more in the sprit of the ALGOL 60 report but the published form confirms to the syntax of ALGOL 60 as described in the report.