A discussion is presented as to how simulation can be used as an effective management tool to reduce costs by predicting many software requirements and design problems that are inherent in the development of real-time...
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A discussion is presented as to how simulation can be used as an effective management tool to reduce costs by predicting many software requirements and design problems that are inherent in the development of real-time computer programs. Historically, simulation has been applied primarily to system performance evaluation and logic verification, and only recently has been formally used to help control the development of the operational program in a U. S. Navy tracking system. Since the technique is still under evaluation, the paper discusses the general concepts.
This paper applies the concepts of hierarchical levels of abstraction and structured programming to the design of a large program system. An operating system for a multiprocessor installation is specified that support...
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This paper applies the concepts of hierarchical levels of abstraction and structured programming to the design of a large program system. An operating system for a multiprocessor installation is specified that supports a large number of concurrently active processes and provides a virtual store for them. The specification is in an extended version of PASCAL, a high-level language.
Description of a set of tools used for the prediction and improvement of program behavior in a segmented virtual memory. Three components are presented: a method for measuring the intersegment dynamic reference patter...
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Description of a set of tools used for the prediction and improvement of program behavior in a segmented virtual memory. Three components are presented: a method for measuring the intersegment dynamic reference pattern, a clustering algorithm for the improvement of locality, and a model and simulator of program behavior.
An attempt is made to clarify certain generally-accepted beliefs regarding software, such as: software represents a growing proportion of total data processing expenditure; and software outlasts hardware.
An attempt is made to clarify certain generally-accepted beliefs regarding software, such as: software represents a growing proportion of total data processing expenditure; and software outlasts hardware.
An example is presented to illustrate how monitors can be employed in building non-trivial concurrent programs. The utility of the monitor concept is evaluated by comparing the results with another solution of the sam...
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An example is presented to illustrate how monitors can be employed in building non-trivial concurrent programs. The utility of the monitor concept is evaluated by comparing the results with another solution of the same problem that did not employ monitors. Performance measurements are also given of various test runs when applying the monitor solution, as a multiprocessing program, to a dual processor configuration. It is concluded that the monitor concept is indeed an effective tool for building concurrent system programs. Furthermore, the concept can be applied as a useful design methodology, irrespective of the implementation mechanisms. Highly modular and structured systems will result with minimal opportunities for obscure time-dependent bugs and deadlock situations.
Vista, one of the first implementations of techniques for assertion synthesis, is described in graphical and equation form. Examples showing the range of Vista and the techniques it employs and implementation and curr...
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Vista, one of the first implementations of techniques for assertion synthesis, is described in graphical and equation form. Examples showing the range of Vista and the techniques it employs and implementation and current limitations are presented.
An approach for solving turbulence problem in fluid flows requires that the nonlinear Poisson equation DEL **2(a) equals f(a) be solved repeatedly. The large data base associated with such problems together with the i...
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An approach for solving turbulence problem in fluid flows requires that the nonlinear Poisson equation DEL **2(a) equals f(a) be solved repeatedly. The large data base associated with such problems together with the inherent difficulty of solving this equation require computers with large primary memory and high parallelism of computation. Instead of using specially designed computers (SIMD or MIMD), the use of a network of general purpose computing elements is proposed. The solution of the equation on such a network requires the development of a nonnegligeable amount of software. In this paper, the author discusses only SOR-type algorithms for solving the Poisson equation DEL **2(a) equals b with Dirichlet's boundary conditions and partitioning schemes for implementing these methods on a network of computing elements. The importance of solving the latter equation efficiently lies in that algorithms for solving the former equation require the repeated solution or approximated solution of the second equation.
This article describes an operating system for use in a reconfigurable redundant computer system employing a synchronized multicomputer organization. The ″synchronous″ executive used in conjunction with a multicompu...
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This article describes an operating system for use in a reconfigurable redundant computer system employing a synchronized multicomputer organization. The ″synchronous″ executive used in conjunction with a multicomputer provides for a fault-tolerant computer system in which the software operation is insensitive to the level of redundancy, computer malfunctions, and individual computer re-initializations. This system supported by the synchronous executive provides for independence of the application and executive software from redundancy management.
Modern implementation of the low cost, reliable software requires management enforcement of standardization of techniques and conventions for program design, specification, coding, and testing. The new tools of struct...
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Modern implementation of the low cost, reliable software requires management enforcement of standardization of techniques and conventions for program design, specification, coding, and testing. The new tools of structured programming and higher order software serve in this capacity. Traditional project management and organization do not provide sufficient control and coordination for the efficient or proper use of these devices. By employing modern concepts of management and information systems in conjunction with the software techniques, a total project environment can be created which is capable of producing consistent, low cost, reliable software systems.
On-line visualization and computational steering of pal-allel scientific applications has been widely recognized as the key, to better insight and understanding of the observed simulation. Front the parallel program d...
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ISBN:
(纸本)0818682558
On-line visualization and computational steering of pal-allel scientific applications has been widely recognized as the key, to better insight and understanding of the observed simulation. Front the parallel program developer's point of view further problems arise and need to be solved. The behavior and performance of parallel programs does not only depend on the input data brit also on inter-process communication. To reflect this fact we propose a novel combination of on-line visualization, computational steering of parallel High Performance Computing applications and controlled deterministic execution. Both, the visualization and the classical part of steering is based on the VIPER tool. For the control of the communication we rely on a tool called coder, which was developed to test and control communication by the nse of control patterns. Finally, VIPER and codex form a environment for tuning, steering and testing based on VIPER's extended programming model.
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