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41.
利用RCM(随机选取法)解反应流爆轰问题时,掌握影响流动参数随机涨落的主要因素是选择适当计算参数、保证得到正确结果的关键。各种流动参数的随机涨落相互关联,只需要搞清楚炸药未反应质量分数的随机涨落并做出分析,其它流动参数涨落的情况也就清楚了。给出了影响未反应质量分数涨落的因数,同时还给出了具体算例,检验所得结论的正确性。 相似文献
42.
The head-on collision of normal shock waves in dusty gases has been investigated numerically, using the modified random-choice method. The results concerning the various flow field properties as well as the waves configuration were compared with those of a pure gas case. 相似文献
43.
提出了在组合算法设计和组合算法选择方面所应当遵循的三个原则,即通用性、可计算性和较少的信息冗余量,并初步分析了它们之间的相互关系.通过分析,提示了组合算法的设计方法,改进方向和优化技术. 相似文献
44.
This paper investigates the exact and approximate spectrum assignment properties associated with realizable output-feedback pole-placement type controllers for single-input single-output linear time-invariant time-delay systems with commensurate point delays. The controller synthesis problem is discussed through the solvability of a set of coupled diophantine equations of polynomials. An extra complexity is incorporated to the above design to cancel extra unsuitable dynamics being generated when solving the above diophantine equations. Thus, the complete controller tracks any arbitrary prefixed (either finite or delaydependent) closed-loop spectrum. However, if the controller is simplified by deleting the above mentioned extra complexity, then the robust stability and approximated spectrum assignment are still achievable for a certain sufficiently small amount of delayed dynamics. Finally, the approximate spectrum assignment and robust stability problems are revisited under plant disturbances if the nominal controller is maintained. In the current approach, the finite spectrum assignment is only considered as a particular case to the designer‘s choice of a (delay-dependent) arbitrary spectrum assignment objective. 相似文献
45.
Hitting probabilities and the Hausdorff dimension of the inverse images of a class of anisotropic random fields 下载免费PDF全文
Let X = {X(t):t ∈ R~N} be an anisotropic random field with values in R~d.Under certain conditions on X,we establish upper and lower bounds on the hitting probabilities of X in terms of respectively Hausdorff measure and Bessel-Riesz capacity.We also obtain the Hausdorff dimension of its inverse image,and the Hausdorff and packing dimensions of its level sets.These results are applicable to non-linear solutions of stochastic heat equations driven by a white in time and spatially homogeneous Gaussian noise and anisotropic Guassian random fields. 相似文献
46.
在全相对论理论框架下,利用多组态Dirac-Fock(MCDF)方法,系统计算了NⅡ离子2p4f—2p3d的辐射跃迁概率,得到的结果与已有实验值符合很好.具体计算中,详细分析了相对论效应、电子关联、弛豫效应、Breit相互作用和量子电动力学(QED)效应对能级精细结构及辐射跃迁概率的影响.结果表明:相对论效应、电子关联和弛豫效应对NⅡ 2p4f-2p3d辐射跃迁概率有很重要的影响,考虑了这些效应后计算值得到明显改善. 相似文献
47.
48.
This paper presents a weight sensitivity algorithm that can be used to investigate a portion of weight space of interest to the decision maker in a goal or multiple objective programme. The preferential information required from the decision maker is an initial estimate of their starting solution, with an equal weights solution being used as a default if this is not available, and preference information that will define the portion of weight space on which the sensitivity analysis is to be conducted. The different types of preferential information and how they are incorporated by the algorithm are discussed. The output of the algorithm is a set of distinct solutions that characterise the portion of weight space searched. The possible different output requirements of decision makers are detailed in the context of the algorithm.The methodology is demonstrated on two examples, one hypothetical and the other relating to predicting cinema-going behaviour. Conclusions and avenues for future research are given. 相似文献
49.
Laurence S. Rothman 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(11):1514-1515
The publication by G.H. Dieke and H.M. Crosswhite (JQSRT 1962;2:97-199) is a classic paper detailing the spectroscopy of the A2Σ+←X2Π bands of the hydroxyl radical (OH) in the ultraviolet region. It soon became the basis of astrophysical modeling, most subsequent theoretical and laboratory studies of the OH individual line parameters, and a host of other applications. 相似文献
50.
This paper shows a computational method for optimizing the location of a store on a network in a competitive environment, assuming that consumers probabilistically choose stores following the Huff model (1963) and that the store can be located on a continuum of a network. This method gives the exact optimal solution with the computational order of n
N
2 logn
N
where n
N
is the number of nodes of the network. 相似文献