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51.
Marc Dubreuil Christian Gagné Marc Parizeau 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(1):229-235
This paper introduces a new mathematical model of the master-slave architecture for distributed evolutionary computations (EC). This model is validated using a concrete implementation based on the Distributed BEAGLE C++ framework. Results show that contrary to (current) popular belief, master-slave architectures are able to scale well over local area networks of workstations using off-the-shelf networking equipment. The main properties of the master-slave are also compared with those of the more mainstream island-model. 相似文献
52.
We consider a system defined as the product of a finite set of periodic systems on cyclic groups. It is of interest to determine if certain subgroups and unions of subgroups of the state set are reachable from a specified initial state, and in particular to determine the computational complexity of verifying such reachability. These questions are motivated by certain problems that arise in the modelling and control of discrete event systems and certain forms of periodic scheduling. Our main result is that deciding whether or not the union of a certain set of subgroups is reachable or not is NP-complete. 相似文献
53.
Hartouni E.P. Jensen D.A. Klima B. Kreisler M.N. Rabin M.S.Z. Uribe J. Church M. Gara A. Gottschalk E. Hylton R. Knapp B.C. Sippach F.W. Stern B. Wiencke L. Christian D. Gutierrez G. Holmes S.D. Strait J.B. Wehmann A. Avilez C. Correa W. Rosales A. Forbush M. Huson F.R. White J. 《IEEE transactions on nuclear science》1989,36(5):1480-1484
A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented 相似文献
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This paper describes how SWoRD (scaffolded writing and rewriting in the discipline), a web-based reciprocal peer review system, supports writing practice, particularly for large content courses in which writing is considered critical but not feasibly included. To help students gain content knowledge as well as writing and reviewing skills, SWoRD supports the whole cycle of writing, reviews, back-reviews, and rewriting by scaffolding the journal publication process as its authentic practice model. In addition, SWoRD includes algorithms that compute individual reviewer’s review accuracy, which is in turn used to support the various drawbacks of reciprocal peer reviews (e.g., variation in motivation or ability of reviewers). Finally, this paper describes an empirical evaluation showing that the SWoRD approach is effective in improving writing quality in content classes. 相似文献
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Numerical Simulation of the Fibre-Motion during the Extrusion of Short-Fibre-Reinforced Glass-Melts Fibre-reinforced materials are characterized by an anisotropic behaviour of the mechanical properties, which is caused by the alignment of the embedded fibres. In the case of short-fibre-compounds this behaviour is strongly influenced by the mechanism of flow during the manufacturing process. Numerical simulation Methods are preferentially used to get informations about the orientation of the reinforced fibres at the end of the molding-process and to improve the properties of the compound. For that, a model is developed, which calculates the motion of the short-fibres in the area of flow, basing on a three-dimensional finite-element-computation. Thereby the interaction between the Particular fibres during the orientation process is considered by using an interaction coefficient. Examplified at the extrusion of short fibre reinforced glass-melts, the fibre orientation is determined at models with different geometries of the pressing tool and variable boundary conditions. This procedure allows to determine the influence of the process-parameters On the expected quality of the composite. The represented simulation-model can also be used for other molding- and extrusion-processes of fibre reinforced materials. 相似文献
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Christian Jennifer L.; O'Leary K. Daniel; Vivian Dina 《Canadian Metallurgical Quarterly》1994,8(1):32
Marital discord and depressive symptomatology have repeatedly been found to be associated, but little is known about variables that influence this relationship. Data were collected from 139 couples seeking marital therapy, and analyses were conducted separately by gender. For wives, lower problem-solving ability, physical aggression by the partner, and 1 relationship belief predicted depressive symptomatology after the variance due to marital discord was removed in regression analyses. In addition to these predictors, less spouse-specific assertiveness, unemployment, and 1 other relationship belief were associated with depressive symptomatology for women after the variance due to marital discord was removed in partial correlation analyses. For men, only lower problem-solving ability added to the prediction of depressive symptomatology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献