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排序方式: 共有575条查询结果,搜索用时 15 毫秒
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As a complex system with multiple components usually deteriorates with age, preventive maintenance (PM) is often performed to keep the system functioning in a good state to prolong its effective age. In this study, a nonhomogeneous Poisson process with a power law failure intensity is used to describe the deterioration of a repairable system, and the optimal nonperiodic PM schedule can be determined to minimize the expected total cost per unit time. However, since the determination of such optimal PM policies may involve numerous uncertainties, which typically make the analyses difficult to perform because of the scarcity of data, a Bayesian decision model, which utilizes all available information effectively, is also proposed for determining the optimal PM strategies. A numerical example with a real failure data set is used to illustrate the effectiveness of the proposed approach. The results show that the optimal schedules derived by Bayesian approach are relatively more conservative than that for non‐Bayesian approach because of the uncertainty of the intensity function, and if the intensity function are updated using the collected data set, which indicates more severe deterioration than the prior belief, replacing the entire system instead of frequent PM activities before serious deterioration is suggested. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010 相似文献
3.
针对不同防空导弹武器系统的火控软件之间不能互用的现状,分析了火控系统各主要功能模块之间的接口关系,提出了火控软件通用化设计的思路,并用C++实现了该设计。火控软件的通用化设计值得将来防空导弹能武器系统火控软件的标准化设计和编程借鉴。 相似文献
4.
二轴晶外锥折射的理论分析 总被引:1,自引:0,他引:1
从晶体的简正模方程出发,求得在二轴晶体中,当光线沿第二类光轴(光线轴)方向行进时,所对应的电场矢量和电位移矢量,并通过几何证明,验证所有折射光线在晶体内均在同一锥面上。 相似文献
5.
在舰载多传感器信息融合系统中,对传感器优化分配问题进行了研究.充分考虑目标身份和目标优先级等信息,依据最大信息增益准则,建立了传感器优化分配的数学模型,并对算法进行了仿真实验. 相似文献
6.
In networks, there are often more than one sources of capacity. The capacities can be permanently or temporarily owned by the decision maker. Depending on the nature of sources, we identify the permanent capacity, spot market capacity, and contract capacity. We use a scenario tree to model the uncertainty, and build a multi‐stage stochastic integer program that can incorporate multiple sources and multiple types of capacities in a general network. We propose two solution methodologies for the problem. Firstly, we design an asymptotically convergent approximation algorithm. Secondly, we design a cutting plane algorithm based on Benders decomposition to find tight bounds for the problem. The numerical experiments show superb performance of the proposed algorithms compared with commercial software. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 600–614, 2017 相似文献
7.
应用蚁群算法(ACA)解决车辆巡回保障问题,建立了车辆巡回保障优化数学模型,对轨迹更新规则进行了重新设定,给出了算法的实现步骤。通过算例分析,将计算结果与遗传算法(GA)和粒子群算法(PSO)作了比较,对模型和算法的正确性、高效性和适用性进行了验证。实验结果表明,该算法可以快速、有效求得车辆巡回保障的优化解,得到车辆巡回保障过程中的较优方案。 相似文献
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介绍Petri网的知识表示方法以及案例推理机制的相关内容,提出了一种基于Petri网的案例推理模型,给出了相应的案例检索匹配算法,并将该模型和检索算法应用到网络攻防态势推演系统中,最后重点介绍了该系统的案例库的知识表示。 相似文献
9.
火花 《中国人民武装警察部队学院学报》2010,(10):57-59
做好玉树灾区重建过程中消防工作的意义重大,对重建中面临的消防问题进行分析,提出为保证灾区重建消防安全应注意以下问题:构建灾区防火监督网络、改善消防安全环境、确保消防专业规划的编制和实施、加强消防监督管理、做好灭火救援和抢险救灾准备、强化便民服务措施等。 相似文献
10.
We study a periodic-review assemble-to-order (ATO) system with multiple components and multiple products, in which the inventory replenishment for each component follows an independent base-stock policy and stochastic product demands are satisfied according to a First-Come-First-Served rule. We assume that the replenishment for various component suffers from lead time uncertainty. However, the decision maker has the so-called advance supply information (ASI) associated with the lead times and thus can take advantage of the information for system optimization. We propose a multistage stochastic integer program that incorporates ASI to address the joint optimization of inventory replenishment and component allocation. The optimal base-stock policy for the inventory replenishment is determined using the sample average approximation algorithm. Also, we provide a modified order-based component allocation (MOBCA) heuristic for the component allocation. We additionally consider a special case of the variable lead times where the resulting two-stage stochastic programming model can be characterized as a single-scenario case of the proposed multistage model. We carry out extensive computational studies to quantify the benefits of integrating ASI into joint optimization and to explore the possibility of employing the two-stage model as a relatively efficient approximation scheme for the multistage model. 相似文献