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41.
Nacima Labadie Renata Mansini Jan Melechovský Roberto Wolfler Calvo 《European Journal of Operational Research》2012
The Team Orienteering Problem (TOP) is a known NP-hard problem that typically arises in vehicle routing and production scheduling contexts. In this paper we introduce a new solution method to solve the TOP with hard Time Window constraints (TOPTW). We propose a Variable Neighborhood Search (VNS) procedure based on the idea of exploring, most of the time, granular instead of complete neighborhoods in order to improve the algorithm’s efficiency without loosing effectiveness. The method provides a general way to deal with granularity for those routing problems based on profits and complicated by time constraints. Extensive computational results are reported on standard benchmark instances. Performance of the proposed algorithm is compared to optimal solution values, when available, or to best known solution values obtained by state-of-the-art algorithms. The method comes out to be, on average, quite effective allowing to improve the best know values for 25 test instances. 相似文献
42.
As a class of one-sided two-party computation, unconditionally secure symmetrically private information retrieval (SPIR) is impossible. So the study of quantum symmetrically private information retrieval (QSPIR), i.e., quantum private query (QPQ) with an interesting degree of security is desirable. Known QPQ protocols [Phys. Rev. Lett. 100 (23) (2008) 230502; Phys. Rev. A 84 (2) (2011) 022313; Phys. Rev. A 83 (2011) 022301; Opt. Exp. 20 (16) (2012) 17411–17420] are claimed to be cheat-sensitive, especially not real-time. It is natural to ask whether we can design a QPQ protocol with real-time security check. In this paper, we introduce an untrusted third party and propose a framework of one-sided two-party quantum computation protocols with real-time security check. For clarity and without loss of generality, we demonstrate a concrete QPQ example under this framework by improving Gao et al's protocol [Opt. Exp. 20 (16) (2012) 17411–17420]. We discuss the security of the protocol and show that it really has real-time security check. The proposed framework paves the way for the design of one-sided two-party quantum computation protocols. 相似文献
43.
民营检测服务发展迅速,已成为我国科学研究和质量控制的重要组成部分. 结合客户走访,阐述了民营检测服务的发展背景,以及当前客户服务现状和问题,并对客户服务的未来进行了展望,以期为民营第三方检测机构的优质客户服务提供参考. 相似文献
44.
A two‐level hierarchical parallelization scheme including the second‐order Møller–Plesset perturbation (MP2) theory in the divide‐and‐conquer method is presented. The scheme is a combination of coarse‐grain parallelization assigning each subsystem to a group of processors, with fine‐grain parallelization, where the computational tasks for evaluating MP2 correlation energy of the assigned subsystem are distributed among processors in the group. Test calculations demonstrate that the present scheme shows high parallel efficiency and makes MP2 calculations practical for very large molecules. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011 相似文献
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46.
已有研究一般直接假设指令驱动市场中的知情交易者总是选择市价单进行交易,本文则基于现实交易状况.建立了一个理论模型.分析拥有私有信息的知情交易者组合使用限价委托单和市价委托单的决策问题.具体给出了不同私有信息状态下知情交易者的组合下单选择。 相似文献
47.
基于MAS的智能诊断技术集成方法研究 总被引:3,自引:0,他引:3
对于复杂分布式故障诊断的特点,集成多种智能方法求解是一种有效的途径.但如何确定这些诊断方法的相对诊断能力是基于多代理技术的故障诊断系统中的一个关键问题.文章基于问题求解的粒度理论,在对设备故障域进行分解的基础上,提出了基于多代理技术的三层评估模型,不仅能对诊断专家的诊断能力进行评估,而且也能对多诊断专家的协调诊断能力进行评估.该方法简化了问题求解的难度,提高了多专家评价的精度.可广泛应用于多诊断专家代理联盟的创建和诊断结论的融合中. 相似文献
48.
基于粒度的多方法评价结论一致性研究 总被引:1,自引:0,他引:1
引入多方法评价结论粒度一致的概念,定义了多方法评价结论粒度一致的粒度计算公式,运用粒度计算公式对一个评价问题的结果进行了粒度一致性分析. 相似文献
49.
公共资本对产出及私人资本的动态冲击效应研究 总被引:1,自引:0,他引:1
王亚芬 《数学的实践与认识》2012,42(5):37-43
估算了我国总的资本存量和公共资本存量,并从资本存量的角度基于结构向量自回归模型(SVAR)研究了公共资本对私人资本和产出的动态影响.通过实证研究得出以下结论:1)在我国公共资本对私人资本具有先"挤入"后"挤出"的效应.给公共资本一个百分点的冲击,在第'三年使得私人资本增加0.5个百分点.2)产出对公共资本冲击的响应更加快速和直接,给公共资本一个百分点的冲击会使得产出在第2期时增长0.8个百分点,但是这种正的响应会逐渐减弱,并在第6期后不再显著.3)方差分解的结果表明,私人资本对产出的贡献率要大于公共资本对产出的贡献率,私人资本对产出贡献率的最大值为61%,而公共资本对产出贡献率的最大值为28%. 相似文献
50.
The central theme of this paper is that we propose an efficient protocol for comparing the equal information with the help of a third party (TP). We assume that TP is semi-honest, i.e., TP executes the protocol loyally, keeps a record of all its intermediate computations and might try to steal the players’ private inputs from the record, but he cannot be corrupted by the adversary. The security of this protocol with respect to various kinds of attacks is discussed. Our protocol utilizes the triplet entangled states and the simple single-particle measurement. The particles carried the secret messages do not be repeatedly transmitted. The players’ messages are divided into many groups. Sometimes, the protocol is already successfully completed, but all data are not compared. Thus, many time and huge quantum resources can be saved. 相似文献