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81.
XIAN He-qun FENG Deng-guo 《通讯和计算机》2007,4(3):44-51
Even with attractive computational advantages, mobile agent technology has not developed its full potential due to various security issues. This paper proposes a method called Private Key Consignment to solve the problem of how to protect the data carried by mobile agents. It exploits new functionalities and mechanism provided by the trusted computing technology, and adopts both public key and symmetric key cryptographic means for data and key protection. The most notable feature of this method is that it protects the private key of the agent by consigning it to a tamper proof hardware, thus, enabling convenient and secure use of the private key. It provides a new scheme of mobile agents' data protection. 相似文献
82.
Kuo-Ming Chao Muhammad Younas Nick Godwin Pen-Choug Sun 《International Journal of Wireless Information Networks》2006,13(2):141-150
The popularity of grid services has widened their application to numerous domains and increased the utilization of computational resources. In order to create more incentives for the resources owners to lease their resources and prevent users from wasting the resources, the introduction of a market-oriented grid is inevitable. However, the issues for the negotiation between service provider and consumer over the supply and demand of resources can be complex, with highly interdependent issues. In this research, a simulated automated negotiation mechanism including a co-evolutionary mechanism and a modified game theory approach is proposed, to assist them in reaching an agreement over the conflicting issues. In the proposed architecture, the co-evolution process is able to reduce the multiple dimensional search space into a two-dimension search space and identify the appropriate negotiation strategies for the negotiating agents to form a payoff matrix which can be used for the game theory related stage of their interaction. The multiple stage negotiation process is introduced to improve the negotiation result. In this paper, an application which requires a large amount of computational resources to process the data generated from mobile devises is used to demonstrate that the proposed system is able to resolve the conflicts and obtain a valid solution. 相似文献
83.
Children between 7 and 8 years old took pan in a staged event at school and 1 week later were assessed using a short form of the Wechsler Intelligence scale for children (third edition) and measures of metamemory, narrative ability, and socioeconomic status. Two weeks following the event, children either received narrative elaboration training (NET; K.J. Saywitz & L. Snyder, 1996) and were prompted with the four NET cue cards at interview; received verbal prompts corresponding to the cue card categories, but without prior training; or were presented with the cards at interview without prior training. Children given verbal labels as prompts recalled as much information as children who received NET training and cue cards. Measures of intelligence were predictive of amount recalled for cards-only children but not for the other 2 groups, indicating that differences in recall between low- and high-IQ groups were attenuated when recall was supported by NET training or verbal prompting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
论企业竞争情报信息系统的构建与重要性 总被引:1,自引:0,他引:1
简要地述叙了现代企业构建竞争情报信息系统的必要性,介绍了竞争情报信息的构建与应用以及该系统在企业中所起的重要作用。 相似文献
85.
The mobile ad hoc network (MANET) has recently been recognized as an attractive network architecture for wireless communication. Reliable broadcast is an important operation in MANET (e.g., giving orders, searching routes, and notifying important signals). However, using a naive flooding to achieve reliable broadcasting may be very costly, causing a lot of contention, collision, and congestion, to which we refer as the broadcast storm problem. This paper proposes an efficient reliable broadcasting protocol by taking care of the potential broadcast storm problem that could occur in the medium-access level. Existing protocols are either unreliable, or reliable but based on a too costly approach. Our protocol differs from existing protocols by adopting a low-cost broadcast, which does not guarantee reliability, as a basic operation. The reliability is ensured by additional acknowledgement and handshaking. Simulation results do justify the efficiency of the proposed protocol. 相似文献
86.
The Grid shows itself as a globally distributed computing environment, in which hardware and software resources are virtualized to transparently provide applications with vast capabilities. Just like the electrical power grid, the Grid aims at offering a powerful yet easy‐to‐use computing infrastructure to which applications can be easily ‘plugged’ and efficiently executed. Unfortunately, it is still very difficult to Grid‐enable applications, since current tools force users to take into account many details when adapting applications to run on the Grid. In this paper, we survey some of the recent efforts in providing tools for easy gridification of applications and propose several taxonomies to identify approaches followed in the materialization of such tools. We conclude this paper by describing common features among the proposed approaches, and by pointing out open issues and future directions in the research and development of gridification methods. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
87.
88.
本文介绍了一种新的数字式定温热偶真空计,它具有精度高、工作可靠、结构简单、操作方便等优点。文中具体阐述了微机系统的工作原理,并提供了结构原理框图。概述了研制中的关键技术问题,即用微机软件对非线性进行补偿的方法。最后介绍了该真空计的主要算法及应用实例。 相似文献
89.
面向智能计算的记忆结构理论综述 总被引:5,自引:0,他引:5
本文从智能计算角度出发,对记忆的总体结构、信息表征及记忆模型等方面的理论作一综述。并在分析、比较了这些理论与AI中的相关理论差异的基础上,对面向智能计算的记忆理论研究方法与方向作了扼要讨论。 相似文献
90.
对于某些容错计算系统,由于成功与故障之间没有明确的界限,用传统的可靠性指标难以准确地评价其容错性能,为此一些学者提出了若干与性能相关的可靠性指标。本文将这些指标概括成三类(即基于瞬时性能的指标、基于累积收益的指标和率模可靠性指标)加以介绍,并简要介绍了它们的求解方法。 相似文献