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991.
曹华清 《重庆科技学院学报(社会科学版)》2003,18(1):83-85,92
适应不良问题已困扰着相当一部分大学生 ,由此出现程度不同的心理障碍 ,试就此问题作心理原因探析 ,并提出相应的对策 相似文献
992.
正面扣球是排球教学中的主要教学环节与难点,文章着重分析了扣球技术的教学方法与重点环节,并结合实际教学经验,提出合理性建议。 相似文献
993.
994.
Guohong Cao 《Knowledge and Data Engineering, IEEE Transactions on》2003,15(5):1251-1265
Caching frequently accessed data items on the client side is an effective technique for improving performance in a mobile environment. Classical cache invalidation strategies are not suitable for mobile environments due to frequent disconnections and mobility of the clients. One attractive cache invalidation technique is based on invalidation reports (IRs). However, the IR-based cache invalidation solution has two major drawbacks, which have not been addressed in previous research. First, there is a long query latency associated with this solution since a client cannot answer the query until the next IR interval. Second, when the server updates a hot data item, all clients have to query the server and get the data from the server separately, which wastes a large amount of bandwidth. In this paper, we propose an IR-based cache invalidation algorithm, which can significantly reduce the query latency and efficiently utilize the broadcast bandwidth. Detailed analytical analysis and simulation experiments are carried out to evaluate the proposed methodology. Compared to previous IR-based schemes, our scheme can significantly improve the throughput and reduce the query latency, the number of uplink request, and the broadcast bandwidth requirements. 相似文献
995.
In this paper, we present a logic system for probabilistic belief named PBL,which expands the language of belief logic by introducing probabilistic belief. Furthermore, we give the probabilistic Aumann semantics of PBL. We also list some valid properties of belief and probabilistic belief, which form the deduction system of PBL. Finally, we prove the soundness and completeness of these properties with respect to probabilistic Aumann semantics. 相似文献
996.
信任管理在电子商务中的实现 总被引:6,自引:0,他引:6
在电子商务中,信任已经成为谈判策略中的一个重要因素,信任管理也成为安全服务的重要组成部分。本文给出了信任管理在电子商务中的实现。 相似文献
997.
本文介绍了第四代呼叫中心的一般结构和功能,并针对在具体的实现过程中通常会遇到的要求,探讨并指出了在其中给出用户定义的CTI接口的方法,并给出处理实例。 相似文献
998.
Li-Sheng Hu Lam J. Yong-Yan Cao Hui-He Shao 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2003,33(1):149-155
In this paper, we consider the H/sub 2/ sampled-data control for uncertain linear systems by the impulse response interpretation of the H/sub 2/ norm. Two H/sub 2/ measures for sampled-data systems are considered. The robust optimal control procedures subject to these two H/sub 2/ criteria are proposed. The development is primarily concerned with a multirate treatment in which a periodic time-varying robust optimal control for uncertain linear systems is presented. To facilitate multirate control design, a new result of stability of hybrid system is established. Moreover, the single-rate case is also obtained as a special case. The sampling period is explicitly involved in the result which is superior to traditional methods. The solution procedures proposed in this paper are formulated as an optimization problem subject to linear matrix inequalities. Finally, we present a numerical example to demonstrate the proposed techniques. 相似文献
999.
1000.
G. Cao S. C. K. Shiu X. Wang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2003,7(8):491-499
Case-based reasoning (CBR) means reasoning from prior examples and it has considerable potential for building intelligent assistant system for the World Wide Web. In order to develop successful Web-based CBR systems, we need to select a set of representative cases for the client side case-base such that this thin client is competence in problem solving. This paper proposes a fuzzy-rough method of selecting cases for such a distributed CBR system, i.e., a thin client system (a smaller case-base with rules) connected to a comparatively more powerful server system (the entire original case-base). The methodology is mainly based on the idea that an original case-base can be transformed into a smaller case-base together with a group of fuzzy adaptation rules, which could be generated using our fuzzy-rough approach. As a result, the smaller case-base with a group of fuzzy rules will almost have the same problem coverage as the entire original case-base. The method proposed in this paper, consists of four steps. First of all, an approach of learning feature weights automatically is used to evaluate the importance of different features in a given case-base. Secondly, clustering of cases is carried out to identify different concepts in the case-base using the acquired feature weights. Thirdly, fuzzy adaptation rules are mined for each concept using a fuzzy-rough method. Finally, a selection strategy which based on the concepts of case coverage and reachability is used to select representative cases. The effectiveness of our method is demonstrated experimentally using some testing data in the travel domain.
This project is supported by the Hong Kong Polytechnic University Grant G-V957 and H-ZJ90. 相似文献