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71.
We discuss algorithms for learning and revising user profiles that can determine which World Wide Web sites on a given topic would be interesting to a user. We describe the use of a naive Bayesian classifier for this task, and demonstrate that it can incrementally learn profiles from user feedback on the interestingness of Web sites. Furthermore, the Bayesian classifier may easily be extended to revise user provided profiles. In an experimental evaluation we compare the Bayesian classifier to computationally more intensive alternatives, and show that it performs at least as well as these approaches throughout a range of different domains. In addition, we empirically analyze the effects of providing the classifier with background knowledge in form of user defined profiles and examine the use of lexical knowledge for feature selection. We find that both approaches can substantially increase the prediction accuracy. 相似文献
72.
VPDN企业端解决方案 总被引:1,自引:0,他引:1
从虚拟专用拨号网(VPDN)结构的基本原理、隧道协议、认证方式等方面概述了中国联通开展VPDN业务的实施步骤和解决VPDN企业端的5种模式,并介绍了中国石油天然气管道电信公司实现VPDN企业端的具体方案。 相似文献
73.
74.
Distributed Coordination and Workflow on the World Wide Web 总被引:5,自引:0,他引:5
Antonietta Grasso Jean-Luc Meunier Daniele Pagani Remo Pareschi 《Computer Supported Cooperative Work (CSCW)》1997,6(2-3):175-200
This paper describes WebFlow, an environment thatsupports distributed coordination services on theWorld Wide Web. WebFlow leverages the HTTP Webtransport protocol and consists of a number of toolsfor the development of applications that require thecoordination of multiple, distributed servers.Typical applications of WebFlow include distributeddocument workspaces, inter/intra-enterprise workflow,and electronic commerce. In this paper we describe thegeneral WebFlow architecture for distributedcoordination, and then focus on the environment fordistributed workflow. 相似文献
75.
In this paper we report the evolution of the polar cluster like behavior with the incorporation of Ti4+ ion in BaZrO3 Ceramics. Dielectric behavior of BaZrxTi(1−x)O3 (x = 1.00, 0.95, 0.90, 0.85) ceramics is studied in the temperature range from 300 to 30 K. Polar cluster like behavior becomes more prominent with the increase in content of Ti4+ ion. The dielectric relaxation is analyzed by Vogel–Fulcher relation and Arrhenius law. Frequency dependence of dielectric constant and low loss tangent of these materials can be useful for the potential applications at low temperature. 相似文献
76.
For the past decade, the Taiwanese government has applied the policy of “North heavy, South light” to put more emphasis on development in northern Taiwan instead of the south. This has resulted in uneven development between the northern and southern regions, especially when introducing, developing, and supporting high technology and resource allocation in education. Industry clusters have become the centerpiece of economic development policy in many parts of the world. In this study, it is assumed that there are two categories of less-advantaged regions in Taiwan: (1) older industrialized regions dominated by labor-intensive/capital-intensive industries, and (2) industrial regions that have merged with potential high-technology small firms but still lack infrastructure. This study discusses the following points: (a) How do industrial clusters work in action? (b) What barriers do less-advantaged industrial clusters face? (c) What action strategies promote less-advantaged industrial clusters? 相似文献
77.
FTP是网络系统提供的基本服务之一.用户可以通过FTP上传和下载文件。本文介绍Linux系统的FTP服务器的原理以及建立FTP服务器和对FTP用户的磁盘配额进行设置。 相似文献
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79.
ASP技术由于其方便 ,灵活及可扩充性等特点和简明、高效的技术优势 ,在Web数据库的开发中获得了广泛的应用。简述了开发Web数据库的重要性 ,介绍了ASP技术的特点及其数据库访问原理 ,ADO对象。实例介绍了ASP实现医院门诊在线查询的方法 相似文献
80.
Stateful session handoff for mobile WWW 总被引:1,自引:0,他引:1
This paper proposes a web session handoff system that can hand over not only stateless but also stateful sessions between homogenous and heterogeneous user devices to enable uninterrupted and seamless web access. The proposed system adopts a proxy-based approach and an optional client-assisted scheme in order to track and hand over session information. In the proposed system, a session is registered at a User Agent Proxy (UAP) and then tracked by the UAP so that the session can be handed over from one device via the UAP to another device. In addition to session information tracked by a UAP, the UAP can hand over more comprehensive session information by using the client-assisted scheme. Compared with client-based approaches, our design has several advantages, such as less modification to user devices, practicability, and fault tolerance. We have implemented a UAP on a PC and client programs for both PC and PDA. The implementation can successfully hand over between PC and PDA a stateful session for online shopping applications. 相似文献