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41.
本文介绍了椭圆工件机器视觉检测系统的构成和软件功能模块,重点阐述了统计聚类和Hough变换相结合检测椭圆像素尺寸的新算法。在降低Hough变换参数维度的情况下,利用椭圆自身特征减少无效数据统计存储量。 相似文献
42.
基于MPI的FDTD并行算法及其优化策略 总被引:1,自引:1,他引:0
由高性能PC机通过网络互联构成的集群(COW)并行计算系统上应用基于消息传递(Message Passing)的方式实现FDTD的并行算法,获得了足够的加速比,有效地解决了传统的FDTD方法计算电大尺寸目标电磁散射问题时的不足.通过区域分割,各个子区域在边界处与其相邻的子区域进行场值的数据传递,从而实现了FDTD算法的并行化.利用并行FDTD方法研究了电磁波的介质层的散射,结果表明并行算法和串行计算结果的一致性,并有效提高计算效率.最后还给出了对算法进行通信隐藏的优化方法,进一步提高了并行计算的效率. 相似文献
43.
Isaac J. Sledge Timothy C. Havens Jacalyn M. Huband James C. Bezdek James M. Keller 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(12):1125-1142
As humans, we have innate faculties that allow us to efficiently segment groups of objects. Computers, to some degree, can
be programmed with similar categorical capabilities, which stem from exploratory data analysis. Out of the various subsets
of data reasoning, clustering provides insight into the structure and relationships of input samples situated in a number
of distributions. To determine these relationships, many clustering methods rely on one or more human inputs; the most important
being the number of distributions, c, to seek. This work investigates a technique for estimating the number of clusters from a general type of data called relational
data. Several numerical examples are presented to illustrate the effectiveness of the proposed method. 相似文献
44.
45.
介绍一种使用WinHex软件恢复找回u盘文件的方法,利用这种方法,u盘使用者通过一些简单的操作步骤,可尝试对偶尔出现的文件误删、误格式化操作进行恢复,挽回损失。 相似文献
46.
本文针对复杂任务分析中的高度耦合任务不易分解且需重构排序的问题,提出了一种基于聚类分析与改进时间-耦合执行序列的自适应任务分解方法。在矩阵最值遴选模型和任务序列转移策略相结合的基础上,设计了基于中间任务序列的任务矩阵分割算法;并进一步采用粒度自主循环调整机制,最终实现了复杂任务的自适应解耦分析。仿真验证结果表明,该方法能够有效实现复杂任务的解耦及序列重构,在作战任务分析领域具有很好的推广应用前景。 相似文献
47.
《材料科学技术学报》2019,35(6):1008-1016
The multi-component composition characteristics of high-temperature near-α Ti alloys were investigated in the present work by means of a cluster formula approach. The uniform cluster formula [CN12 cluster](glue atom)3 for the hexagonal close-packed α solid solution was first obtained based on the Friedel oscillation theory, with a total atom number in the formula of Z = 16. Then it was analyzed that the Z values in the cluster composition formulas of typical near-α Ti alloys are within the range of Z = 16.00 ˜ 16.30, being perfectly consistent with the ideal Z = 16. Based on it, a series of new alloys with Z = 16 and with Nb/Ta substitution for Mo in Ti1100 alloy were designed, suction-cast into φ 6 mm rods, and then heat-treated with solid solution and aging. It was found that the alloy with co-addition of Mo, Ta and Nb has a high strength and good ductility at both room and high temperatures. More importantly, the additions of Nb and Ta can contribute to the formation of continuous and compact Al2O3 scales, resulting in an obvious improvement of oxidation resistances at both 923 K and 1073 K. The effects of Mo, Ta and Nb on the oxidation behaviors of the designed alloys at 1073 K were further discussed. 相似文献
48.
In this paper, we develop mathematical models for simultaneous consideration of suitability and optimality in asset allocation. We use a hybrid approach that combines behavior survey, cluster analysis, analytical hierarchy process and fuzzy mathematical programming. 相似文献
49.
Sriparna Saha Author Vitae Sanghamitra Bandyopadhyay Author Vitae 《Pattern recognition》2010,43(3):738-751
In this paper the problem of automatic clustering a data set is posed as solving a multiobjective optimization (MOO) problem, optimizing a set of cluster validity indices simultaneously. The proposed multiobjective clustering technique utilizes a recently developed simulated annealing based multiobjective optimization method as the underlying optimization strategy. Here variable number of cluster centers is encoded in the string. The number of clusters present in different strings varies over a range. The points are assigned to different clusters based on the newly developed point symmetry based distance rather than the existing Euclidean distance. Two cluster validity indices, one based on the Euclidean distance, XB-index, and another recently developed point symmetry distance based cluster validity index, Sym-index, are optimized simultaneously in order to determine the appropriate number of clusters present in a data set. Thus the proposed clustering technique is able to detect both the proper number of clusters and the appropriate partitioning from data sets either having hyperspherical clusters or having point symmetric clusters. A new semi-supervised method is also proposed in the present paper to select a single solution from the final Pareto optimal front of the proposed multiobjective clustering technique. The efficacy of the proposed algorithm is shown for seven artificial data sets and six real-life data sets of varying complexities. Results are also compared with those obtained by another multiobjective clustering technique, MOCK, two single objective genetic algorithm based automatic clustering techniques, VGAPS clustering and GCUK clustering. 相似文献
50.
并行FFT是解决大数据量FFT运算耗时过久的重要途径,在PC机群上实现并行FFT是一种低成本、高效率的解决方案。本文讨论了PC机群环境下MPI并行FFT实现,并利用建立的平台,对并行算法进行了测试,得出了一些有意义的结论和方法。 相似文献