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131.
The complex velocity field of an oscillating Couette flow is measured with a Laser-Doppler velocimeter. Different evaluation methods are used for the determination of material functions such as relaxation times and the dynamic complex viscosity. 相似文献
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LIU Baijun ZHENG Zhongguo & ZHAO Hui School of Mathematical Sciences Peking University Beijing China Department of Statistics Central China Normal University Wuhan China 《中国科学A辑(英文版)》2005,48(11):1517-1530
Chain graph (CG) is a general model of graphical Markov models. Some different chain graphs may describe the same conditional independence structure, then we say that these CGs are Markov equivalent. In 1990 Frydenberg showed that every class of Markov equivalent CGs has a CG which is called the largest chain graph with the greatest number of lines. This paper presents an efficient algorithm for finding the largest chain graph of the corresponding Markov equivalent class of a given CG. The computational complexity of the algorithm is O(n3). It is more efficient than the complexity O(n!) of the present algorithms. Also a more intuitive graphical characterization of the largest chain graph is provided based on the algorithm in this paper. 相似文献
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Luc G. Chalmet Richard L. Francis Antoon Kolen 《European Journal of Operational Research》1981,6(2):117-124
Given n planar existing facility locations, a planar new facility location X is called efficient if there is no other location Y for which the rectilinear distance between Y and each existing facility is at least as small as between X and each existing facility, and strictly less for at least one existing facility. Rectilinear distances are typically used to measure travel distances between points via rectilinear aisles or street networks. We first present a simple arrow algorithm, based entirely on geometrical analysis, that constructs all efficient locations. We then present a row algorithm which is of order n(log n) that constructs all efficient locations, and establish that no alternative algorithm can be of a lower order. 相似文献
136.
H. P. Benson 《Journal of Optimization Theory and Applications》1982,38(3):341-361
In this paper, we present several new properties of the admissible points of a convex polyhedron. These properties can be classified into two categories. One category concerns the characterization and generation of these points. The other category concerns the circumstances under which these points are efficient solutions for linear multiple-objective programs with nonnegative criteria matrices. To illustrate some of the potential utility of these properties, we describe their application to two practical problems. These problems are the linear multiple-objective problem with interval coefficients and the problem of optimizing over the efficient set.This research was supported, in part, by the Center for Econometrics and Decision Sciences, University of Florida, Gainesville, Florida. 相似文献
137.
研究了高电荷态离子129Xeq+(q=25,26,27)入射金属Mo表面产生的特征X射线谱.实验结果表明,在束流强度小于120nA条件下,高电荷态离子129Xeq+可以激发Mo的L壳层特征X射线谱.单离子X射线相对产额可达10-8量级,特征X射线的相对产额随入射离子的动能和电荷态(势能)的增加而增加.通过Mo原子的Lα1特征X射线谱,利用Heisenberg不确定关系对Mo原子的第M能级寿命进行了估算. 相似文献
138.
We present an algorithm to compute rth roots in $\mathbb{F}_{q^m}We present an algorithm to compute rth roots in
with complexity ?[(log m + r log q) m log q] if (m,q) = 1 and either (q(q−1),r) = 1 or r|(q−1) and ((q−1)/r,r) = 1. This compares well to previously known algorithms, which need O(r m3 log3 q) steps.
Paulo S. L. M. Barreto: Supported by Scopus Tecnologia S. A.
José Felipe Voloch: Supported by NSA grant MDA904-03-1-0117. 相似文献
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