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111.
将理想全二维磁流体(MHD)稳定性数值代码GATO成功移植到HL-2A高性能计算系统,并用其模拟研究了HL-2A装置一次典型弹丸注入实验的等离子体的理想MHD稳定性。利用HL-2A装置第4050次放电的实验数据,应用EFIT代码重建了几个时间片的平衡位形,然后应用GATO代码对每个平衡位形的MHD稳定性进行了计算。通过对结果进行分析比较得出初步结论,由于弹丸注入而造成的反剪切位形的致稳作用,可以提高等离子体的约束性能。 相似文献
112.
工件带到达时间的两阶段柔性流水作业的近似算法 总被引:1,自引:0,他引:1
研究了工件带到时间的两阶段柔性流水作业的排序问题,基于求解流水作业和平行机问题的算法思想,提出两个相应的近似算法H(R)和H(MR(?)),证明了这两个算法的最坏情况性能比分别为3-1/m和2/5-1/m,讨论了界的紧性,并利用数值模拟以分析算法与最优值的近似性能比. 相似文献
113.
The Onsager reciprocity relation and generalized efficiency of a thermal Brownian motor 总被引:1,自引:0,他引:1 下载免费PDF全文
Based on a general model of Brownian motors, the Onsager
coefficients and generalized efficiency of a thermal Brownian motor
are calculated analytically. It is found that the Onsager
reciprocity relation holds and the Onsager coefficients are not
affected by the kinetic energy change due to the particle's motion.
Only when the heat leak in the system is negligible can the
determinant of the Onsager matrix vanish. Moreover, the influence of
the main parameters characterizing the model on the generalized
efficiency of the Brownian motor is discussed in detail. The
characteristic curves of the generalized efficiency varying with
these parameters are presented, and the maximum generalized
efficiency and the corresponding optimum parameters are determined.
The results obtained here are of general significance. They are used
to analyze the performance characteristics of the Brownian motors
operating in the three interesting cases with zero heat leak,
zero average drift velocity or a linear response relation, so that
some important conclusions in current references are directly
included in some limit cases of the present paper. 相似文献
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115.
Solving large scale linear systems efficiently plays an important role in a petroleum reservoir simulator, and the key part is how to choose an effective parallel preconditioner. Properly choosing a good preconditioner has been beyond the pure algebraic field. An integrated preconditioner should include such components as physical background, characteristics of PDE mathematical model, nonlinear solving method, linear 相似文献
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118.
This paper deals with the analysis of an M/M/c queueing system with setup times. This queueing model captures the major characteristics of phenomena occurring in production
when the system consists in a set of machines monitored by a single operator. We carry out an extensive analysis of the system
including limiting distribution of the system state, waiting time analysis, busy period and maximum queue length.
AMS subject classification: 90B22, 60K25 相似文献
119.
Akihiko Ohtsu 《Optics Communications》2010,283(20):3831-3837
The author investigated second-harmonic (SH) wave patterns generated by focused vortex beams with radial and azimuthal polarizations. Expressions for electric field components near the focus through a dielectric interface were obtained based on vector diffraction theory. Furthermore, the (110) and (001) planes of a crystal classified in the symmetry group 4?3m were considered as second order nonlinear optical medium to analyze nonlinear polarization and the intensity distributions of the SH wave in the far-field were simulated for topological charge m = 1 and 2. Numerical simulations indicated that the intensity and emission pattern of the SH wave depended principally on the electric field component and distribution near the focus. In particular, for the (001) plane, the intensity of the SH wave was strongly correlated with the existence of a longitudinal electric field. 相似文献
120.
结合高职院校"双师型"教师实训教学的关键行动,构建了高职院校"双师型"教师实训教学绩效评价的指标体系,并结合实例将隶属度转换算法应用于具体的"双师型"教师实训教学绩效评价之中. 相似文献