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131.
Service Oriented Architectures, which allow for the integration of different subsystems and of applications running on different devices and platforms, may be very suitable to solve the problem of service personalization in large smart environments like cities, where the number of potential users and potentially available services is rapidly growing. Taking this into account, we have designed an agent-based service oriented architecture for smart spaces. Two of the greatest challenges in the design of such a solution are providing effective device, service and context federation and composition mechanisms and handling user mobility. For the first challenge, we have designed a hierarchical architecture and developed a set of inheritance, aggregation and access mechanisms for devices, services and context. To handle user mobility, we have followed three different strategies, using stationary, mobile or nomadic agents. In this paper, we describe the main aspects of our architecture and perform an experimental evaluation to determine the advantages and drawbacks of the different strategies.  相似文献   
132.
Although developments on software agents have led to useful applications in automation of routine tasks such as electronic mail filtering, there is a scarcity of research that empirically evaluates the performance of a software agent versus that of a human reasoner, whose problem-solving capabilities the agent embodies. In the context of a game of a chance, namely Yahtzee©, we identified strategies deployed by expert human reasoners and developed a decision tree for agent development. This paper describes the computer implementation of the Yahtzee game as well as the software agent. It also presents a comparison of the performance of humans versus an automated agent. Results indicate that, in this context, the software agent embodies human expertise at a high level of fidelity.  相似文献   
133.
This paper describes the implementation of evolutionary techniques for information filtering and collection from the World Wide Web. We consider the problem of building intelligent agents to facilitate a person's search for information on the Web. An intelligent agent has been developed that uses a metagenetic algorithm in order to collect and recommend Web pages that will be interesting to the user. The user's feedback on the agent's recommendations drives the learning process to adapt the user's profile with his/her interests. The software agent utilizes the metagenetic algorithm to explore the search space of user interests. Experimental results are presented in order to demonstrate the suitability of the metagenetic algorithm's approach on the Web.  相似文献   
134.
We present a novel mobile code management environment,currently under design and development. Our design employs anopen architecture, suitable for ``plug-and-play' with COTS andother groups' tools. While we have studied new algorithms, costand objective functions, and other fundamental issues, the maincontribution of this experimental research work is in the environmentitself. It should be noted that networked platforms, such asthe World Wide Web, are inherently not suitable for traditional,predictable real-time applications. Thus, real-time concernsnecessarily need to be blended with others concerns, and thetarget applications, making use of our environment, will toobe a blend of partially hard real-time and partially (or mostly)soft-real- time ones. The prototype environment will thereforesupport performance-based analysis and management focusing notonly on predictability but also on compilation, efficiency, safetyand other tradeoffs. We have selected the Java language and itsbytecode format as a representation for mobile code as well asa language for our implementation.  相似文献   
135.
Information agent technology for the Internet: A survey   总被引:8,自引:0,他引:8  
The vast amount of heterogeneous information sources available on the Internet demands advanced solutions for acquiring, mediating, and maintaining relevant information for the common user. Intelligent information agents are autonomous computational software entities that are especially meant to (1) provide pro-active resource discovery, (2) resolve information impedance of information consumers and providers, and (3) offer value-added information services and products. These agents are supposed to cope with the difficulties associated with the information overload of the user, preferably just in time.

Based on a systematic classification of intelligent information agents, this paper presents an overview of the basic key enabling technologies needed to build such agents, and respective examples of information agent systems currently deployed on the Internet.  相似文献   

136.
空间元数据研究及应用   总被引:16,自引:0,他引:16  
分布式地理空间数据的快速导航一直是分布式GIS研究的重点。针对地理空间数据的特点,在已有空间元数据标准的基础上,构造了一个分层空间元数据库框架,设计实现了不同级别的空间元数据库,很好地组织和管理了分布在网络上的地理空间数据库及其数据;在分层空间元数据库的支持下,基于地图(图层)的4个基本要素(专题、空间范围、地层、时间),设计了一个面向用户的地理空间数据请求描述规范,并据此实现了一个基于多Agent的分布工地理空间数据查找策略,该策略能够很好地确定性或非确定性地理空间数据快速导航的要求。  相似文献   
137.
This paper outlines a generic evaluation methodology for multimedia and real time applications. It concentrates on the application layer and the service aspect. Principles of software evaluation for quality assessment and measurement for networked services and distributed applications are used to present a specific method for measuring important characteristics. The method and the measurement procedure allow comparison of the actual characteristics of service quality with the required characteristics and thresholds. The proof of concepts will be made by the implementation of quality measurement agents following the approach outlined in this paper. Our approach of performing service level management (SLM) with agent technology is distributed, slim, minimizable to the maximum, independent in its methodology and offers comparable, objective results.  相似文献   
138.
氟碳防水防油剂的研究新进展   总被引:8,自引:1,他引:8  
韩红滨  魏慧英  曹成波  吴克安 《精细化工》2004,21(7):537-539,543
介绍了氟碳防水防油剂的结构与性能特征、合成方法,综述了近几年氟碳防水防油剂的研究新进展,预测了其发展趋势。  相似文献   
139.
氟硅酸钠的防结块研究   总被引:1,自引:0,他引:1  
周斌  王美燕 《化肥工业》2003,30(2):21-23
分折了氟硅酸钠结块的原因,介绍了防结块的措施,并对表面活性剂和惰性物质应用于氟硅酸钠的防结块进行了研究。结果表明,硫酸巴盐或磺酸盐型表面活性剂应用于氟硅酸钠的防结块效果显著,选用复配型表面活性剂,即磺酸盐和脂肪酸盐等的复配液效果更佳,用量为0.12%时能确保氟硅酸钠70d不结块。  相似文献   
140.
锡盐着色膜颜色与氧化膜中Sn含量的关系   总被引:1,自引:0,他引:1  
对锡盐电解着色膜的颜色深浅与氧化膜中Sn含量两者之间的关系进行了研究。此外还探讨了锡盐电解着色液中镍离子和亚铁离子在电解着色过程中所起的作用。  相似文献   
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