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31.
模糊聚类在三维地震参数处理中的应用 总被引:1,自引:1,他引:0
三维地震参数是一个庞大的三维数据体,能从不同侧面反映储集层的特征。通过对三维地震参数的分析,可以评估油藏表征的参数(沉积相、构造、生长历史、流体饱和度等)。针对传统的聚类方法不能很好地综合考虑各个参数之间的相似程度,提出了用模糊C-均值聚类(fuzzy c-means clustering,简称FCM)对三维地震参数进行处理。从三维地震参数和油藏表征参数之间的关系出发,采用模糊C-均值聚类方法对三维地震参数进行处理,依此评估油藏表征的参数。测试结果表明,模糊C-均值聚类方法能够对三维地震参数进行较为准确的分类,并为储集层的研究提供了很好的依据。 相似文献
32.
WCDMA的MBMS技术 总被引:2,自引:0,他引:2
主要介绍了基于WCDMA的MBMS技术,给出了其网络架构和技术难点,并对其应用给无线网络带来的影响作了一定深度的探讨。 相似文献
33.
XU Shun dou 《中国邮电高校学报(英文版)》2002,9(2)
1 IntroductionInordertoimprovethequalityofpostalserviceandtakeadvantageofautomatedmailsortingequip ments,ithasbeendeterminedtoconstructthepostalareacenterofficesysteminChinaPostalSer vice (CPS) .ThecruxoftheproblemfacedbyCPSistoredesignthepostalcommunica… 相似文献
34.
Tao Li 《Machine Learning》2006,62(3):199-215
Clustering is the problem of identifying the distribution of patterns and intrinsic correlations in large data sets by partitioning
the data points into similarity classes. This paper studies the problem of clustering binary data. Binary data have been occupying
a special place in the domain of data analysis. A unified view of binary data clustering is presented by examining the connections
among various clustering criteria. Experimental studies are conducted to empirically verify the relationships. 相似文献
35.
36.
文章较系统地论述了车铣复合机床设计方案的形成过程,同时分析了该设计方案的持点,并简要介绍了该产品的主要技术参数和用途,简评了该产品的技术水平。 相似文献
37.
Xin Song Xiaoyu Qi Bin Hao Yinbo Qu 《European Journal of Lipid Science and Technology》2008,110(12):1095-1101
Although lipases are widely applied in a wide variety of reactions, available information on the factors that are responsible for the substrate specificities of lipases from different sources is scarce. In this paper, nine lipase‐producing microorganism strains were isolated from oil‐containing samples. The properties of these enzymes, including pH optima, temperature optima, thermal stability, and pH stability, vary significantly with the different sources from which these lipases were isolated. The substrate specificities of the nine lipases, including fatty acid and positional specificities, were also studied. The fatty acid specificities of the nine lipases were observably different toward 15 substrates with different carbon chain lengths, different saturation degrees and different side chains. The lipases from S3 Penicillium citrinum (PCL), MJ1 Aspergillus niger (ANL), MJ2 Aspergillus oryzae (AOL), YM Bacillus coughing (BCL), S9 Geotrichum candidum (GCL), and S11 Candida lypolytica (CLL) showed the strongest specificities to short‐chain esters, and the other lipases showed strong selectivity for medium‐ or long‐chain and branched esters. The positional specificities were examined by analyzing the hydrolytic products of triolein catalyzed by the nine lipases, using TLC. The lipases can be mainly classified into two groups by their specificities for the ester bond at position 2 of triglycerides; one group can selectively hydrolyze the ester bond at position 2 of the triglycerides, the other group cannot. All these nine lipases were divided into four groups by hierarchical clustering analysis on the basis of the results of fatty acid and positional specificities. 相似文献
38.
采用通用蒙特卡罗粒子输运程序MCNP/38计算低环径比Tokamak(紧凑环或球形环)聚变堆第一壁及中心导体上的中子壁负荷分布和核热沉积分布,并与常规Tokamak堆第一壁上中子壁负荷分布和核热沉积分布进行比较、分析。结果表明,在中子壁负荷归一化为1MW/m2时,与常规Tokamak相比,在低环径比Tokamak堆第一壁及中心柱表面上中子壁负荷分布峰值并不比常规Tokamak堆第一壁上的峰值高,而且低于低环径比Tokamak堆整个第一壁上的平均值,而中心柱上的核热沉积峰值稍高于常规Tokamak堆第一壁上的核热沉积峰值,但对较高中子壁负荷情况,中心导体柱上的核热沉积和辐照损伤仍可能是比较严重和值得特别研究的问题。 相似文献
39.
Makoto Kasu Rangaiya Rao Susumu Noda Akio Sasaki 《Journal of Electronic Materials》1991,20(9):691-693
Properties of theDX centers in Al0.5Ga0.5As bulk alloy (b-AL), (AlAs)2 (GaSa)2 ordered superlattice (o-SL) and (AlAs)
m
(GaAs)
n
disordered superlattice (d-SL) (m = 1, 2, 3,n = 1, 2, 3) with the same macroscopic composition were measured and compared. By deconvolution of deep level transient spectroscopy
(DLTS) spectrum due to theDX center, we have found a decrease in the number of separate peaks in DLTS spectrum in an intentionally atomic ordered arrangement.
Visiting Scholar of the Japan Society for the Promotion of Science. On leave from Department of Electrical Engineering, San
Jose State University, San Jose, California 95192-0084, USA. 相似文献
40.
Motonobu Yoshikawa Hiroshi Nakajima Takeshi Inada Yasushi Harada Masahiko Amano Yuji Nakata 《Electrical Engineering in Japan》1995,115(7):29-39
A new practical method is proposed which gives a quasi-optimal solution of the dynamic load-dispatching problem formulated by a multiconstraint multiobjective optimization problem. Here, the multiple constraints are rate reserve constraints and power flow ones, and the multiple objectives are fuel cost and CO2 emission. The proposed method is an integration of the following three techniques: (1) “Group Dispatch Scheme,” which is developed by the authors, is used to satisfy a violated constraint easily. This scheme consists of three steps. The first step is to classify all generators into two groups. One is the group which should be more loaded to satisfy the violated constraint, and the other is the should-be less loaded group. The second step is to add some load to the former group, and to subtract the same load from the latter. The third step is to dispatch each group load to each groups generators, respectively; (2) the dynamic load-dispatching algorithm is used which provides, in practical time, quasi-optimal generation trajectories; (3) the conventional weighting parametric method is used to obtain a Pareto optimal solution of multiobjective problems. The effectiveness of the method is clarified by a computer simulation on the actual power system of Kansai Electric Power Company. 相似文献