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941.
粗糙集和信息熵的属性约简算法及其应用   总被引:2,自引:0,他引:2  
吴尚智  苟平章 《计算机工程》2011,37(7):56-58,61
阐述粗糙集理论和信息熵的基本概念,并为寻找属性约简的有效方法,提出一种基于粗糙集和信息熵的属性约简算法。在决策表中添加某个属性引起的互信息变化的大小,以反映该属性的重要性,并求相对约简。研究表明,该算法不仅能得到最优的决策规则,而且能够减少信息系统所需的搜索空间,得到更优的属性约简效果。  相似文献   
942.
现有对订单履行系统的研究存在2处不足:订单履行流程被分解为订单允诺和需求满足两方面,鲜有在同一系统框架下展开研究;订单履行实现涉及众多系统的信息,少有研究其体系架构。为解决上述问题,以按照约束理论构建的统一的订单履行流程为核心,以面向服务架构的Web服务集成技术为支撑,设计与实现了整合式的订单履行系统。该系统在某大型企业中获得成功的应用,验证了该流程及体系架构的可行性。  相似文献   
943.
研究基于图着色理论的频谱分配算法,提出一种改进的最大效用频谱分配算法。该算法生成类似于ISAA算法的用户效用矩阵和相应的干扰矩阵,选择最大效用用户或干扰值为0的用户进行频谱分配。仿真结果表明,该算法能有效减少频谱分配的时间开销,提高频谱的使用效率,最大化认知无线电系统的总效用。  相似文献   
944.
基于信息熵的空间对象群聚类算法   总被引:2,自引:0,他引:2       下载免费PDF全文
刘建兴  鲍培明 《计算机工程》2011,37(16):176-178
针对利用空间关系建立空间对象群聚类的问题,提出一种基于信息熵的空间对象群聚类算法ESOGC。该算法考虑空间数据的复杂性和数据之间的联系,根据邻域范围内信息熵的变化情况,捡起或放下当前空间对象群,从而实现对空间对象群的聚类。实验结果表明,该算法能解决空间对象群中对象类型、对象属性值和对象数量不一致性的问题。  相似文献   
945.
在分析传统互信息法缺陷的基础上,提出一种基于二次TF*IDF的互信息特征选择算法,对仅在一个类别中出现的特征词的重要程度给予再次的衡量,解决了互信息值相等而无法进行有效特征选择的问题。利用贝叶斯分类器对该方法进行验证的结果表明该算法在文本分类效率和正确率上比原有方法有一定的提高。  相似文献   
946.
Quality is an important factor in information systems development (ISD), and ISD team performance closely relates to quality. To better understand ISD teams, we empirically tested a model on ISD team performance by combining socio-technical theory and coordination theory. Using existing empirical studies and data collected from three well-known ISD companies in China, our research results identified influential characteristics of ISD team performance, and revealed similarities and differences between China’s ISD team performance and those in other countries. By the results, we find that knowledge sharing and major do not affect team performance. The compensation satisfaction to job performance is not significant in China, either. Our research provides suggestions for building and supporting ISD teams that could lead to performance improvements.  相似文献   
947.
The present study examined whether traditional gender role expectations (Eagly, 1987) influence behaviors in non-traditional contexts such as online virtual environments. Participants were 352 Second Life users who reported their activities and experiences in Second Life. Results indicated that men and women differed in the types of activities they engaged in a manner predicted by social role theory. Specifically, as compared to women, men were more likely to report building things (e.g. objects), to own and work on their own virtual property, and were less likely to change their avatar’s appearance. Women, as compared to men, were more likely to meet people, shop, regularly change their avatar’s appearance, and buy clothes/objects for their avatar. The present study adds to our understanding of how traditional gender role expectations may carry over to online virtual worlds and influence online behavior.  相似文献   
948.
Comparing tree-structured data for structural similarity is a recurring theme and one on which much effort has been spent. Most approaches so far are grounded, implicitly or explicitly, in algorithmic information theory, being approximations to an information distance derived from Kolmogorov complexity. In this paper we propose a novel complexity metric, also grounded in information theory, but calculated via Shannon's entropy equations. This is used to formulate a directly and efficiently computable metric for the structural difference between unordered trees. The paper explains the derivation of the metric in terms of information theory, and proves the essential property that it is a distance metric. The property of boundedness means that the metric can be used in contexts such as clustering, where second-order comparisons are required. The distance metric property means that the metric can be used in the context of similarity search and metric spaces in general, allowing trees to be indexed and stored within this domain. We are not aware of any other tree similarity metric with these properties.  相似文献   
949.
Geometry of Interaction is a transcendental syntax developed in the framework of operator algebras. This fifth installment of the program takes place inside a von Neumann algebra, the hyperfinite factor. It provides a built-in interpretation of cut-elimination as well as an explanation for light, i.e., complexity sensitive, logics.  相似文献   
950.
Managing service quality is vital to retain customer satisfaction and augment revenues for any business organization. Often it is difficult to assess service quality due to lack of quantifiable measures and limited data. In this paper, we present a hybrid approach based on SERVQUAL and fuzzy TOPSIS for evaluating service quality of urban transportation systems. The proposed approach consists of three steps. The first step involves development of a SERVQUAL based questionnaire to collect data for measuring transportation service quality. The participants provide linguistic assessments to rate the service quality criteria and the alternatives. In step 2, the linguistic ratings are combined through fuzzy TOPSIS to generate an overall performance score for each alternative. The alternative with the highest score is finally chosen. In step 3, sensitivity analysis is conducted to evaluate the influence of criteria weights on the decision making process.The strength of the proposed approach is its practical applicability and ability to provide solution under partial or lack of quantitative information. An application of the proposed approach for evaluation of service quality of metro in Montreal is provided.  相似文献   
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