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田国梁 《高校应用数学学报(A辑)》1992,7(2):264-271
具Weibull强度函数的非齐次Poisson过程经常被用来分析可修系统的失效模式.基于极大似然估计,Engelhardt & Bain(1978)导出了Weibull过程将来第k次失效时间的经典预测区间.在本文中,我们用无信息联合验前分布,根据Weibull过程的前n次失效时间,给出了建立将来第k次失效时间的Bayes预测区间的方法,并说明了如何应用这些方法。 相似文献
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Guoliang Xue 《Journal of Global Optimization》1994,4(2):187-208
In this paper, we propose a new kind of simulated annealing algorithm calledtwo-level simulated annealing for solving certain class of hard combinatorial optimization problems. This two-level simulated annealing algorithm is less likely to get stuck at a non-global minimizer than conventional simulated annealing algorithms. We also propose a parallel version of our two-level simulated annealing algorithm and discuss its efficiency. This new technique is then applied to the Molecular Conformation problem in 3 dimensional Euclidean space. Extensive computational results on Thinking Machines CM-5 are presented. With the full Lennard-Jones potential function, we were able to get satisfactory results for problems for cluster sizes as large as 100,000. A peak rate of over 0.8 giga flop per second in 64-bit operations was sustained on a partition with 512 processing elements. To the best of our knowledge, ground states of Lennard-Jones clusters of size as large as these have never been reported before.Also a researcher at the Army High Performance Computing Research Center, University of Minnesota, Minneapolis, MN 55415 相似文献
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I.IntroductionUndcrwatersoundrevcrberationhasrccentlybecomeatopicofgreatinterestlI-3l.Sincethcrcverberationincludescombincdeffcctsofsoundpropagahonandscattering,andthesoundpropagationinshallowwaterismuchmorecomplicatedthanthatinthedeepsea,itisnecessarytOstudycarefullybothintheoryandexperimcnt.Fortheshortrangereverberationinshal1owwatcrtheray-basedmodelisavai1ab1e,whilefOr1ongrangethewave-basedmodelmustbeusedbecauscofcomp1icatcdmu1tipaths,refractioneffcctsandfrequencydependence.Thenorma1-mode… 相似文献
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Wenjun Qu Xiaoye Zhang Dan Wang Yaqiang Wang Guoliang Cao Huizheng Che Liwen Yan 《中国颗粒学报》2006,4(1):20-24
Based on 481-year records of historical dust storm (DS) and Dryness-Wetness Index (DWI) at 120 sites, spatial distribution characteristics of dryness-wetness (DW) in typical dust storm years (DS years) and in non-dust storm years (non-DS years) were derived for continental China. In DS years, most of the sites were drier than in normal years while in non-DS years wetter than normal, and the variation of DWI in DS years was larger than that in non-DS years. The relative instability and increased regional difference of atmospheric circulation in DS years might have induced more frequent DS events and dry-wet abnormality in continental China. In DS years the latitudinal (north-south) dry-wet difference was larger than that in non-DS years, that is, north China was even much drier than south China. This might be attributed to increased latitudinal differences of thermal and pressure gradients in DS years, resulting in the southward withdrawal of precipitation and increase of DS events. 相似文献
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基于有限差分束传播法的Mach-Zehnder型波导电光调制器的模拟设计 总被引:4,自引:0,他引:4
针对掺钛铌酸锂Mach-Zehnder型波导电光调制器的结构及折射率分布,运用有限差分束传播方法(FD BPM)进行模拟计算,取得了二维情况下的最佳设计尺寸.在此基础上,把所得的设计结果与原有的用快速傅里叶束传播方法(FFT BPM)所得的结果进行比较和分析.结果显示,运用有限差分束传播方法不仅取得了预期的结果,而且,这种方法比原有的快速傅里叶束传播方法更快捷和方便,是器件设计的理想和现实的数值模拟工具. 相似文献
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