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191.
192.
1 Introduction “Spatial Angles Calculations” means that all the calculations of given and unknown parameters are related to calculating angles in 3D space. The functions and relevant parameters in 3D space are much more complicated than that in 2D space, i.e. on a plane. Professor Sun, based on his research conducting for more than a decade, presented a series of new algorithms to calculate angles in space which are valuable in both theory and applications[1]. The authors found that, in g… 相似文献
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Kenichi Miura 《Parallel Computing》1988,8(1-3):91-100
The EGS4 code, developed at Stanford Linear Accelerator Center, simulates electron-photon cascading phenomena. The original code is inherently sequential: processing one particle at a time. This paper reports on a series of experiments in parallelizing different versions of EGS4. Our parallel experiments were run on a 30-processor Sequent Balance B21 and a 6-processor Symmetry S27. We have considered the following approaches for parallel execution of this application code:
- 1. (1) Original sequential version modified for parallel processing: 1 processor;
- 2. (2) Version 1 run multiprocessed: 1 to 29 processors;
- 3. (3) Sequential version modified for large-grain parallel processing: 1 procssor;
- 4. (4) Version 3 run using the Sequent Microtasking Library: 1 to 29 processors.
For each approach, we discuss the relative advantages and disadvantages in the areas of coding effort, understandability and portability, as well as performance, and outline a new parallelization approach we are currently pursuing based on Large-Grain Data Flow techniques. 相似文献
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Diane J. Cook 《Applied Intelligence》1991,1(2):133-144
Analogical planning provides a means of solving engineering problems where other machine learning methods fail. Unlike many machine learning paradigms, analogy does not require numerous previous examples or a rich domain theory. Instead, analogical planners adapt knowledge of solved problems in similar domains to the current problem. Unfortunately, the analogical planning task is an expensive one. While the process of forming correspondences between a known problem and a new problem is complex, the problem of selecting a base case for the analogy is virtually intractable.This paper addresses the issue of efficiently forming analogical plans. The Anagram planning system is described, which takes advantage of the massively parallel architecture of the Connection Machine to perform base selection and map formation. Anagram provides a tractable solution to analogical planning, with a complexity that is sublinear in the size of the plans.This paper describes the Anagram system and its parallel algorithms. The paper also presents theoretical analyses and empirical results of testing the system on a large database of plans from the domain of automatic programming. 相似文献
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乌江索风营水电站坝址区分布有7个堆积体,其成因有崩塌堆积、蠕变-拉裂-崩解堆积、塌滑堆积及混和堆积等.在勘察过程中采用了地质测绘、钻探、硐探、物探、科研试验等多种勘察方法与手段,在勘察成果基础上对堆积体稳定性进行了分析,并结合对工程的不同影响提出了相应的工程处理措施. 相似文献
199.
Gerald Andrews Emison 《Canadian Metallurgical Quarterly》2004,20(2):56-61
Today’s engineering managers who use total quality management (TQM) face the challenge of moving it from adoption to seamless incorporation into their organizations. Both the application and the theory of TQM can be advanced through an examination of the philosophy of pragmatism and the sciences of adaptation. Pragmatism provides a philosophy that establishes a theory for incorporating TQM into engineers’ management practice; it derives its epistemology from actual experience. In essence, pragmatism suggests that practical experience, such as that gained from the continuous improvement of and experimentation with TQM, provides the basis for successful organizational performance. The sciences of adaptation identify the characteristics of organizations that promote successful adaptation. They suggest that incremental adjustments to ongoing change are the keys to effective and successful growth. This paper explores both philosophy and science to identify actions and attitudes that can enable the success of TQM in an organization. 相似文献
200.
Celso M. F. Lapa Cludio M. N. A. Pereira Paulo F. Frutuoso e Melo 《Reliability Engineering & System Safety》2003,81(1):103-109
In order to maximize systems average availability during a given period of time, it has recently been developed a non-periodic surveillance test optimization methodology based on genetic algorithms (GA). The fact of allowing non-periodic tests turns the solution space much more flexible and schedules can be better adjusted, providing gains in the overall system average availability, when compared to those obtained by an optimized periodic test scheme. This approach, however, turns the optimization problem more complex. Hence, the use of a powerful optimization technique, such as GA, is required.Considering that some particular features of certain systems can turn it advisable to introduce other specific constraints in the optimization problem, this work investigates the application of seasonal constraints for the set of the Emergency Diesel Generation of a typical four-loop pressurized water reactor in order to planning and optimizing its surveillance test policy. In this analysis, the growth of the blackout accident probability during summer, due to electrical power demand increases, was considered. Here, the used model penalizes surveillance test interventions when the blackout probability is higher.Results demonstrate the ability of the method in adapting the surveillance test policy to seasonal constraints. The knowledge acquired by the GA during the searching process has lead to test schedules that drastically minimize test interventions at periods of high blackout probability. It is compensated by more frequent redistributed tests through the periods of low blackout probability in order to improve on the overall average availability at the system level. 相似文献