A general method to parallelize any tridiagonal solver is presented. The method, based ona suitable decomposition of the numerical problem, is rather simple but efficient. The communication overhead stays small and wi...
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A general method to parallelize any tridiagonal solver is presented. The method, based ona suitable decomposition of the numerical problem, is rather simple but efficient. The communication overhead stays small and with respect to stability and vectorizability the parallel algorithms have nearly the same qualities as their sequential counterparts. When applied to standard sequential solvers the method yields some well-known as well as many new parallel algorithms.
The authors introduce a formalism which allows to treat computerarchitecture as a formal optimization problem. They apply this to the design of shared memory parallel machines. Present computers of this type support ...
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A lattice Monte Carlo study of the color fields in the sector of static qq¯ pairs is reported. Lattice sum rules relating these observables to the qq¯ potential are tested in detail. As a by-product the β f...
A lattice Monte Carlo study of the color fields in the sector of static qq¯ pairs is reported. Lattice sum rules relating these observables to the qq¯ potential are tested in detail. As a by-product the β function of the SU(2) Yang-Mills theory is determined with high accuracy.
The authors introduce a formalism which allows to treat computerarchitecture as a formal optimization problem. They apply this to the design of shared memory parallel machines. Present computers of this type support ...
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The authors introduce a formalism which allows to treat computerarchitecture as a formal optimization problem. They apply this to the design of shared memory parallel machines. Present computers of this type support the programming model of a shared memory. But simultaneous access to the shared memory by several processors is in many situations processed sequentially. Asymptotically good solutions for this problem are offered by theoretical computerscience. The authors modify these constructions under engineering aspects and improve the price/performance ratio by roughly a factor of 6. The resulting machine has surprisingly good price/performance ratio even if compared with distributed memory machines. For almost all access patterns of all processors into the shared memory, access is as fast as the access of only a single processor. The re-engineered machine is based on Fluent Machine.< >
CyberQuest(CQ)is a Problem Solving and Innovation Support *** has been employed in over 300 cases to help people come up with ideas for a particular problem or opportunity and look for ways to implement the *** employ...
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CyberQuest(CQ)is a Problem Solving and Innovation Support *** has been employed in over 300 cases to help people come up with ideas for a particular problem or opportunity and look for ways to implement the *** employs hypermedia(computer,audio,video,and even aroma)systems to help in a six step process to accomplish problem solving,design,and ***
作者:
ZITZMAN, LHFALATKO, SMPAPACH, JLDr. Lewis H. Zitzman:is the group supervisor of the Advanced Systems Design Group
Fleet Systems Department The Johns Hopkins University Applied Physics Laboratory (JHU/APL). He has been employed at JHU/APL since 1972 performing applied research in computer science and in investigating and applying advanced computer technologies to Navy shipboard systems. He is currently chairman of Aegis Computer Architecture Data Bus and Fiber Optics Working Group from which many concepts for this paper were generated. Dr. Zitzman received his B.S. degree in physics from Brigham Young University in 1963 and his M.S. and Ph.D. degrees in physics from the University of Illinois in 1967 and 1972 respectively. Stephen M. Falatko:was a senior engineering analyst in the Combat Systems Engineering Department
Comptek Research Incorporated for the majority of this effort. He is currently employed at ManTech Services Corporation. During his eight-year career first at The Johns Hopkins University Applied Physics Laboratory and currently with ManTech Mr. Falatko's work has centered around the development of requirements and specifications for future Navy systems and the application of advanced technology to Navy command and control systems. He is a member of both the Computer Architecture Fiber Optics and Data Bus Working Group and the Aegis Fiber Optics Working Group. Mr. Falatko received his B.S. degree in aerospace engineering with high distinction from the University of Virginia in 1982 and his M.S. degree in applied physics from The Johns Hopkins University in 1985. Mr. Falatko is a member of Tau Beta Pi Sigma Gamma Tau the American Society of Naval Engineers and the U.S. Naval Institute. Janet L. Papach:is a section leader and senior engineering analyst in the Combat Systems Engineering Department
Comptek Research Incorporated. She has ten years' experience as an analyst supporting NavSea Spa War and the U.S. Department of State. She currently participates in working group efforts under Aegis Combat System Doctrin
This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis comp...
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This paper sets forth computer systems architecture concepts for the combat system of the 2010–2030 timeframe that satisfy the needs of the next generation of surface combatants. It builds upon the current Aegis computer systems architecture, expanding that architecture while preserving, and adhering to, the Aegis fundamental principle of thorough systems engineering, dedicated to maintaining a well integrated, highly reliable, and easily operable combat system. The implementation of these proposed computer systems concepts in a coherent architecture would support the future battle force capable combat system and allow the expansion necessary to accommodate evolutionary changes in both the threat environment and the technology then available to effectively counter that threat. Changes to the current Aegis computerarchitecture must be carefully and effectively managed such that the fleet will retain its combat readiness capability at all times. This paper describes a possible transition approach for evolving the current Aegis computerarchitecture to a general architecture for the future. The proposed computer systems architecture concepts encompass the use of combinations of physically distributed, microprocessor-based computers, collocated with the equipment they support or embedded within the equipment itself. They draw heavily on widely used and available industry standards, including instruction set architectures (ISAs), backplane busses, microprocessors, computer programming languages and development environments, and local area networks (LANs). In this proposal, LANs, based on fiber optics, will provide the interconnection to support system expandability, redundancy, and higher data throughput rates. A system of cross connected LANs will support a high level of combat system integration, spanning the major warfare areas, and will facilitate the coordination and development of a coherent multi-warfare tactical picture supporting the future combatant command st
We present a necessary and sufficient condition for an arbitrary matrix A to be totally unimodular. The matrix A is interpreted as the adjacency matrix of a bipartite graph G(A). The total unimodularity of A correspon...
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The estimation of an absolute life expectancy of a structure is a complex process and the results are expected to have relatively large levels of uncertainty. In this study, a comparative analysis is undertaken betwee...
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The estimation of an absolute life expectancy of a structure is a complex process and the results are expected to have relatively large levels of uncertainty. In this study, a comparative analysis is undertaken between two different patrol boats. This is an approach which results in a higher confidence level because certain factors common to both boats can be eliminated by assuming them to be at constant normal levels. The study is limited to the critical forward bottom plating and takes into account the differences in material, plate dimensions, operational profile, structure and loading of the two vessels. Two failure modes, plastic plate deformation and fatigue, are considered, and a novel approach to plate wastage is included. Many factors affect the structural life of a vessel. They include structural type, operational profile, structural details, loads, inspection and maintenance, design methods, safety factors, corrosion, and environmental factors. There are three types of uncertainty associated with these factors; namely, physical randomness, statistical uncertainties, and model uncertainties. The method described is designed to address these uncertainties. The objective of the paper is to present the reliability-based structural life assessment method, and then to use it to evaluate and compare the structural performance of the forward bottom plating of the two patrol boats. The results of the evaluation are presented in the form of graphs and tables in order to facilitate the comparative evaluation. The method is performed within a computer-based format which allows parametric sensitivity analysis of several variables including the size of the plating panel, thickness, operational profile and loading. The sensitivity of the structural life expectancy of the forward bottom plating to variations in these parameters is evaluated.
The authors' premise is that applications have the ability to tolerate certain types of failures under certain situations. This may, in turn, relax the top-level constraint on failure recovery algorithms in the in...
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The authors' premise is that applications have the ability to tolerate certain types of failures under certain situations. This may, in turn, relax the top-level constraint on failure recovery algorithms in the interprocess communication (IPC) layer and allow exploitation of the inherent tolerance of applications to failures in a systematic way to simplify failure recovery. Using this application-driven approach, the authors present a model of a distributed program based on the well-known client-server relationship among the processes of the program. The model reflects certain generic properties of the application layer that can be exploited by the IPC layer during failure recovery. New techniques as to how the properties can be used for recovery are outlined. The authors use remote procedure call and shared variable as communication abstractions for the client and the server processes in the program to communicate with one another. The simplicity and generality of the failure recovery renders the application-driven approach particularly useful in contemporary distributed systems which are large and heterogeneous and hence have complex failure modes.< >
C-calculus is a method for combining less descriptive information for larger sets to obtain detailed descriptions about smaller sets. This is achieved by iteratively taking products of information in the form of C-set...
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