基于分阶段筛选评估的合同网任务分配机制

基于合同网的任务分配机制广泛应用于各领域的多Agent系统中,以解决分布式任务分配问题。在分析经典合同网协议优缺点的基础上,提出了分阶段筛选与招投标协商相结合的任务分配模型。通过招投标的可计算性评估,将主要计算任务放在招投标Agent内部进行并且缩小招投标范围,从而减少通信并提高效率;通过动态确定评估指标提高了机制的通用性。     

关联规则挖掘在发动机故障分析中的应用

大部分关联规则挖掘算法仅以出现频率作为阈值来产生关联规则,然而在发动机故障数据分析领域,很多关键故障的出现机率较低,采用传统的挖掘算法无法适应航空发动机故障分析的需要.提出一种新算法,称为权重式多重支持度关联规则挖掘算法,此算法可针对不同重要度的故障定出不同的支持度阈值,由此产生的关联规则,可以解决高重要度但出现较少的故障不易被挖掘的问题.     

Planning gamma accelerated degradation tests with two accelerating variables

Gamma accelerated degradation tests (ADT) are widely used to assess timely lifetime information of highly reliable products with degradation paths that follow a gamma process. In the existing literature, there is interest in addressing the problem of deciding how to conduct an efficient, ADT that includes determinations of higher stress‐testing levels and their corresponding sample‐size allocations. The existing results mainly focused on the case of a single accelerating variable. However, this may not be practical when the quality characteristics of the product have slow degradation rates. To overcome this difficulty, we propose an analytical approach to address this decision‐making problem using the case of two accelerating variables. Specifically, based on the criterion of minimizing the asymptotic variance of the estimated q quantile of lifetime distribution of the product, we analytically show that the optimal stress levels and sample‐size allocations can be simultaneously obtained via a general equivalence theorem. In addition, we use a practical example to illustrate the proposed procedure.     

基于反正切函数的测试性分配方法

针对现有主流测试性分配方法存在的分配指标过低和过高等不合理问题,分析认为其根源在于现有方法采用线性分配函数,而该函数不符合测试性指标提升规律,为此,构造了一种基于反正切函数的测试性分配函数,设计故障检测率与故障隔离率指标的分配算法,开展案例应用并与经典故障率分配法和综合加权分配法进行对比分析,结果表明随着分配权重(故障率)的变大,本方法分配指标的增幅逐渐减小,不会出现极低指标和超1指标的不合理情形。     

Dynamic routing of prioritized warranty repairs

Recent years have seen a strong trend toward outsourcing warranty repair services to outside vendors. In this article we consider the problem of dynamically routing warranty repairs to service vendors when warranties have priority levels. Each time an item under warranty fails, it is sent to one of the vendors for repair. Items covered by higher priority warranty receive higher priority in repair service. The manufacturer pays a fixed fee per repair and incurs a linear holding cost while an item is undergoing or waiting for repair. The objective is to minimize the manufacturer's long‐run average cost. Because of the complexity of the problem, it is very unlikely that there exist tractable ways to find the optimal routing strategies. Therefore, we propose five heuristic routing procedures that are applicable to real‐life problems. We evaluate the heuristics using simulation. The simulation results show that the index‐based “generalized join the shortest queue” policy, which applies a single policy improvement step to an initial state‐independent policy, performs the best among all five heuristics. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

军用飞机大修效率评估方法

针对航空修理工厂大修效率难以评估的问题,首次提出了军用飞机大修效率评估方法。根据飞机大修工作特点,系统分析了飞机大修效率影响因素,建立了飞机大修效率评估指标体系;运用信息熵理论和灰色系统理论,构建出基于熵权和灰色聚类的评估指标赋权模型;结合实例验证了方法的正确性。     

装备保障人员优化配置方法研究

将装备保障人员按级别分为操作人员、维修人员及管理人员,结合人员进入、培训和退出的状态,构造了状态转移矩阵,求出了各级别人员数量。定义了不同级别针对不同任务的保障效率,按照保障人员完成最高效率任务构建了最优化配置模型。通过实例验证了模型的实用性。     

基于NSGA-Ⅱ的WTA多目标优化(英文)

将多目标遗传算法NSGA-(改进的非支配排序遗传算法)应用于求解武器-目标分配(WTA)问题。首先,针对以往在建立防空型WTA问题的优化模型上的片面性,把WTA问题看做多目标优化问题,建立了综合考虑作战效能和防御效能的WTA双目标优化模型。然后在此基础上,研究和应用了NSGA-来求解WTA问题。最后由仿真算例验证了NSGA-在WTA问题中的应用可行性,表明了NSGA-可以快速地搜索到WTA多目标优化的Pareto最优解集,从而为求解WTA问题提供了一条有效途径。     

某型穿甲弹弹托轻量化仿真研究

为了减小弹托消极质量,提高某型穿甲弹的威力,运用Ansys11.0软件的Workbench平台,采用瞬态动力学方法对某型穿甲弹的发射强度进行了仿真,结果表明:该弹弹托马鞍部和尾椎部的强度裕度较大。通过在马鞍部钻孔和尾椎部开槽,在满足发射强度要求的前提下可减轻弹托质量170 g,从而使该型穿甲弹的炮口初速提高了16.25 m/s,进而使该型穿甲弹对既定目标的有效穿透距离增加了270 m左右。     

多边修正算法中的换顶原理及复杂性分析

对于无向赋权图,利用换顶过程中矩阵翻转与数据块调换时上三角部分数据的变化规律,对权值矩阵的数据进行处理,以完成无向完全图中H圈（H路类似）的修正过程。事实上,多边修正的原理最终是通过变换顶点达到的,而其主要用到的换顶规则是矩阵数据的块调换与翻转,该思想还可以推广到有向图的情形。最后利用换顶原理对多边修正算法进行了复杂性分析,讨论修正边数对复杂性的影响。