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91.
在PKI中,证书路径的构建是非常重要的过程,也许在可信赖的第三方与终端实体之间有多个候选路径,探讨了PKI路径的构建时蚁群算法的应用,并对PKI路径的构建时最短路径问题进行了研究。  相似文献   
92.
Offshore outsourcing to vendors in foreign countries causes unique challenges which need to be understood and managed effectively. This paper explores cultural differences in IS offshoring arrangements involving German client organizations that outsource application development activities to Indian vendors. For this purpose, a research framework is developed based on both theoretical considerations and specific empirical observations from multiple case studies. The goal is to (1) explore the nature of cultural differences in offshore outsourcing arrangements in depth and to (2) analyze the relationship between those cultural differences and offshore outsourcing success. Based on the case findings, implications and practices for the management of offshore development projects are outlined. The results indicate that cultural differences in terms of power distance, IS designer values, and an active versus passive working attitude critically affect several dimensions of relationship quality, thereby influencing offshore outsourcing success. A clear definition of roles and mechanisms, strong leadership, and an active management of culture by adapting to either the client’s or the vendor’s national culture appeared to be effective ways to manage cultural differences.
Armin HeinzlEmail:
  相似文献   
93.
The Internet today is a highly dynamic environment which frequently requires secure communication between peers that do not have a direct trust relationship. Current solutions for establishing trust often require static and application-specific Public Key Infrastructures (PKIs). This paper presents trusted directory services as a key infrastructural technology for setting up secure Internet connections, providing an alternative to application-specific PKIs. The directory securely binds public keys to peers through their names in a flexible way that matches the dynamic nature of the Internet. We elaborate on this concept by showing how the Domain Name System (DNS) and its security extensions (DNSSEC) can be leveraged for establishing secure Transport Layer Security (TLS) connections in a dynamic way. A simple enhancement of the TLS protocol, called Extended TLS (E-TLS), required for this purpose, is proposed. We describe our E-TLS implementation and we conclude with an evaluation of our results.  相似文献   
94.
Real robots should be able to adapt autonomously to various environments in order to go on executing their tasks without breaking down. They achieve this by learning how to abstract only useful information from a huge amount of information in the environment while executing their tasks. This paper proposes a new architecture which performs categorical learning and behavioral learning in parallel with task execution. We call the architectureSituation Transition Network System (STNS). In categorical learning, it makes a flexible state representation and modifies it according to the results of behaviors. Behavioral learning is reinforcement learning on the state representation. Simulation results have shown that this architecture is able to learn efficiently and adapt to unexpected changes of the environment autonomously. Atsushi Ueno, Ph.D.: He is a research associate in the Artificial Intelligence Laboratory at the Graduate School of Information Science at the Nara Institute of Science and Technology (NAIST). He received the B.E., the M.E., and the Ph.D. degrees in aeronautics and astronautics from the University of Tokyo in 1991, 1993, and 1997 respectively. His research interest is robot learning and autonomous systems. He is a member of Japan Association for Artificial Intelligence (JSAI). Hideaki Takeda, Ph.D.: He is an associate professor in the Artificial Intelligence Laboratory at the Graduate School of Information Science at the Nara Institute of Science and Technology (NAIST). He received his Ph.D. in precision machinery engineering from the University of Tokyo in 1991. He has conducted research on a theory of intelligent computer-aided design systems, in particular experimental study and logical formalization of engineering design. He is also interested in multiagent architectures and ontologies for knowledge base systems.  相似文献   
95.
面向空间监视应用的空间目标数据库的建立   总被引:2,自引:0,他引:2  
阐述了面向空间监视应用的空间目标数据库的建立技术与方法,并给出了它在空间监视的目标分类、识别应用中的样例。  相似文献   
96.
DNA计算求解连续空间优化问题   总被引:2,自引:2,他引:0  
首先构造了二进制编码的网络空间,其两个节点连接权的四条边对应到DNA编码,设计了相应的算子起到DNA计算酶的作用,该算法设计使得DNA计算能够求解连续空间优化问题。通过测试函数表明该算法具有较好的收敛速度和稳定性,求解结果非常好。  相似文献   
97.
Web文本特征选择算法的研究   总被引:1,自引:1,他引:0  
以向量空间模型作为Web文本的表示方法,结合Web文本的结构特征对向量空间模型中的特征选择算法进行了分析并加以改进。在改进的算法中,体现出了特征词在Web文档结构中的位置信息;引入了信息论中熵的概念,用词的熵函数对权值进行调整,从而更加准确地选取有效的特征词。实验验证了改进算法的可行性和有效性。  相似文献   
98.
一种虚拟场景控制方法的研究与实现   总被引:3,自引:0,他引:3  
针对虚拟场景中视点控制和模型控制两种情况,研究了应用二维鼠标和三维输入设备拾取三维对象模型、移动对象模型和在虚拟场景中漫游的方法,提出了一种用二维鼠标拾取三维模型的方法——粗区域判断、最近拾取,并基于Vega视景仿真开发平台和VC++提出了一种基于二维鼠标拾取、三维输入设备移动的虚拟场景控制方法。  相似文献   
99.
《Ergonomics》2012,55(8):1661-1666
Abstract

In this paper a summary of the Chinese Ergonomics Society (CES) is introduced. The main ergonomics institutions in China re presented. Some important research projects that are being or have been investigated are mentioned. The teaching of ergonomics in Chinese universities is described. Several titles of publications written by Chinese ergonomists are listed. The characteristics of the ergonomic situation in China are discussed.  相似文献   
100.
通过对穆青新闻思想背景、新闻观念(媒介功能观、舆论观和新闻价值观)和新闻报道方式等方面进行阐述,透视穆青新闻传播思想特点:现实体验的文学化转换;政治语境下的媒体预设;超越事实的意义化表述,并以此挖掘其社会主义性质与新闻专业精神的内在矛盾,揭示其新闻观对后世新闻思想发展的引导价值及现实意义。  相似文献   
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