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991.
The Internet and World Wide Web offer an additional channel for consumers to find, select, and buy products. However, unlike shopping in the traditional store, consumers have no direct contact with human clerks to get the required information in the electronic store. The objective of this paper is to propose a fuzzy constraint satisfaction approach to help buyers find fully satisfactory or replacement products in electronic shopping. For the buyer who can give precise product requirements, the proposed approach can generate product-ranking lists based on the satisfaction degrees of each product to the given requirements. For the buyer who may not input accurate requirements, a similarity analysis approach is proposed to assess buyer requirements automatically during his browsing process. The proposed approach could help buyers find the preferred products on the top of the ranking list without further searching the remaining pages. The experimental results show the applicability of the proposed approach for electronic shopping assistance. 相似文献
992.
Carles Sierra 《Autonomous Agents and Multi-Agent Systems》2004,9(3):285-301
Electronic commerce has been one of the traditional arenas for agent technology. The complexity of these applications has been a challenge for researchers that have developed methodologies, products, and systems, having in mind the specificities of trade, the interaction particularities of commerce, the strict notion of commitment and contract, and the clearly shaped conventions and norms that structure the field. In this paper I survey some key areas for agent technology which, although general, are of special importance in electronic commerce, namely, solid development methodologies, negotiation technologies and trust-building mechanisms. I give examples of systems in which I have directly participated, although I also try to refer to the work of other AgentLink Special Interest Group members over the last few years. 相似文献
993.
The behavioral equivalent of single input single output (SISO) systems are behaviors with two manifest variables. Passive SISO systems can, therefore, be viewed as J-dissipative behaviors with two manifest variables. Here the special matrix J defines a QDF that captures the passivity property of SISO systems. In this paper, we investigate more general QDFs QΦs induced by some operator Φ. These QDFs define some relation between the input, the output and their derivatives of a SISO system. We characterize all behaviors that are dissipative with respect to the prescribed QDF QΦ. In fact, we parametrize all the behaviors dissipative with respect to QΦ in terms of those dissipative with respect to the special QDF QJ induced by the matrix J. Similar results can also be given for lossless systems. 相似文献
994.
This paper analyzes the formulation of energy preserving/decaying schemes for dynamics problems. We argue that any energy preserving/decaying scheme can always be seen as composed of an underlying temporal discretization, that is then slightly modified in order to prove a discrete energy bound within a time step. While the details of the modified scheme depend in a critical way on the governing equations, the underlying discretization can in principle be applied to a variety of models. We review some of the temporal underlying schemes recently proposed in the literature, presenting them with a common notation. We show their similarities and highlight their differences. 相似文献
995.
996.
陈明 《制冷与空调(四川)》2004,18(3):40-42
随着我国目前电力供应的紧张和电价的上调,变频空调以其舒适节能成为市场销售的新亮点.本文通过变频空调的基本原理、使用效果及未来发展趋势来引导消费者正确地加以选择. 相似文献
997.
998.
999.
点源发出的低能量电子波经过样品的散射后,带有物体原子结构信息的散射波(物波)和未被散射的电子波(参考波)在收集平面上相互干涉形成的电子全息图即为低能电子投射全息图.本文在合理的物理模型下,以石墨的晶体结构为试样,通过计算机模拟的方法,首次对低能电子投射全息进行了研究,讨论了一些关键参数对晶体结构电子全息的重现像和分辨率的影响,并且实现了晶体结构三维数值重现,讨论了三维重现的效果. 相似文献
1000.
针对目前地热供暖应用的现状,比较了各种常规的供暖模式的经济及环保效益;介绍了一种全新的地热、高温水源热泵的供暖方案,为低温地热水、地热尾水及其它各种温度在30~60℃之间的中低品位余热水资源提供了一种高效、合理的利用途径. 相似文献