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提出一种基于用户偏好的激励机制,鼓励用户通过提供共享文件和转发操作为系统做出贡献。IMBPC结合了虚拟价格机制和预期文件传输延时,基于用户对价格和延时的偏好度来选择最合适的节点进行文件下载。通过设置模拟实同仅通过虚拟价格机制来激励用户做出贡献的策略进行比较,显示应用IMBPC策略的系统,节点的贡献积极性明显增加。 相似文献
65.
We present a mechanism for reservations of bursty resources that is both truthful and robust. It consists of option contracts
whose pricing structure induces users to reveal the true likelihoods that they will purchase a given resource. Users are also
allowed to adjust their options as their likelihood changes. This scheme helps users save cost and the providers to plan ahead
so as to reduce the risk of under-utilization and overbooking. The mechanism extracts revenue similar to that of a monopoly
provider practicing temporal pricing discrimination with a user population whose preference distribution is known in advance. 相似文献
66.
机构位移仿真分析方法比较研究 总被引:1,自引:1,他引:0
机构位移分析是运动分析中最根本的问题,机构位移分析方程通常是非线性的,只有简单的二级机构才能列出输入变量和输出变量之间的显函数表达式,而在其他情况下,方程的求解就需要利用各种数值解法.以压床六杆机构为研究对象,推导了机构多位移矩阵迭代求解和单一位移精确求解的理论方程,并用上述两种方法对压床六杆机构进行了机构位移仿真计算比较分析,证实单一位移精确求解方法的计算比较简便,求解过程不用推导,一旦确定单一位移值后,可对其它位移进行精确求解,对机构位移仿真计算有一定的实用性,累积误差小,可用于机构运动学设计. 相似文献
67.
Atsushi Kawamoto 《Structural and Multidisciplinary Optimization》2009,37(4):429-433
This paper deals with the design of compliant mechanisms in a continuum-based finite-element representation. Because the displacements
of mechanisms are intrinsically large, the geometric nonlinearity is essential for designing such mechanisms. However, the
consideration of the geometric nonlinearity may cause some instability in topology optimization. The problem is in the analysis
part but not in the optimization part. To alleviate the analysis problem and eventually stabilize the optimization process,
this paper proposes to apply the Levenberg–Marquardt method to the nonlinear analysis of compliant mechanisms. 相似文献
68.
目前,制约竞争情报发展的一个关键问题就是情报的收集与分析手段比较落后,远远不能胜任竞争情报系统所蕴含的特点和功效。本文将竞争情报作为一种特殊的知识,吸纳知识发现理论成果和方法,提升现有竞争情报系统的构造技术,真正做到快速、全面、准确和智能化的竞争情报生成和利用。 相似文献
69.
Donghun Sungcheul Namkuk Chaemook Kyu-Yeul Tae-Wan Jongwon Soo Ho 《Robotics and Computer》2010,26(1):13-23
Shipbuilding processes involve highly dangerous manual welding operations. Welding ship walls inside double-hulled structures presents a particularly hazardous environment for workers. This paper describes the “Rail Runner X” (RRX), a new robotic system that can move autonomously inside the walls of a double-hulled ship and automatically execute the required welding processes. The RRX robotic system is composed of a mobile platform and a welding robot consisting of a 3P3R serial manipulator. The robot is used to weld U-shaped trajectories located between two longitudinal stiffeners. The mobile platform enables traverse movements onto neighboring longitudinal stiffeners. The entire cross section of the robotic system is small enough to be placed inside the double-hulled structure via a conventional access hole from the outside shipyard floor. The overall engineering design process that led to the final robot solution developed is presented in this paper, including kinematic analysis data and experimental results for verifying the autonomous movement and welding performance. 相似文献
70.
Hemalatha ChandrashekharAuthor Vitae Bharat BhaskerAuthor Vitae 《Decision Support Systems》2011,52(1):157-168
This paper develops an automated negotiation procedure inclusive of mechanism design and agent design for bilateral multi-issue negotiations under two-sided information uncertainty. The proposed negotiation mechanism comprises a protocol called MUP (Monotonic Utility-granting Protocol) and a matching strategy called WYDIWYG (What You Display Influences What You Get). The proposed preference elicitation procedure makes the agents faithful surrogates of the user they represent while the proposed Frontier Tracking Proposal Construction Algorithm (FTPCA) makes them learn the opponent's flexibility in negotiation and respond appropriately. The mechanism design and the agent design together help in locating efficient and equitable deals quickly. The efficiency, stability, simplicity, distribution symmetry and incentive compatibility of the proposed procedure are demonstrated through negotiation simulation experiments. 相似文献