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421.
The theory of directed graphs and noncooperative games is applied to the problem of verification of State compliance to international treaties on arms control, disarmament and nonproliferation of weapons of mass destruction. Hypothetical treaty violations are formulated in terms of illegal acquisition paths for the accumulation of clandestine weapons, weapons‐grade materials or some other military capability. The paths constitute the illegal strategies of a sovereign State in a two‐person inspection game played against a multi‐ or international Inspectorate charged with compliance verification. The effectiveness of existing or postulated verification measures is quantified in terms of the Inspectorate's expected utility at Nash equilibrium. A prototype software implementation of the methodology and a case study are presented. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 260–271, 2016 相似文献
422.
The notion of signature has been widely applied for the reliability evaluation of technical systems that consist of binary components. Multi‐state system modeling is also widely used for representing real life engineering systems whose components can have different performance levels. In this article, the concept of survival signature is generalized to a certain class of unrepairable homogeneous multi‐state systems with multi‐state components. With such a generalization, a representation for the survival function of the time spent by a system in a specific state or above is obtained. The findings of the article are illustrated for multi‐state consecutive‐k‐out‐of‐n system which perform its task at three different performance levels. The generalization of the concept of survival signature to a multi‐state system with multiple types of components is also presented. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 593–599, 2017 相似文献
423.
通用装备机械液压系统综合检测试验平台的设计与研制 总被引:7,自引:6,他引:1
针对目前通用装备保障建设过程中存在的保障设备通用性差、综合功能弱、机动性能差及信息化程度低等问题,提出了"划类分组、综合集成、一体通用"的设计思想,研制了可完成军械、装甲、工程、防化、车辆、陆军船艇等装备机械液压系统技术状况检测与评估、故障诊断、部(元)件修后试验与质量评估、信息管理等功能的综合机动平台。重点阐述了平台各系统的设计思想、硬件组成及软件框架。实际应用表明,该平台具有"广谱"、"广域"和"全时"的能力,其推广使用将为通用装备保障由"基于型号"向"基于能力"的建设转型提供成功示范。 相似文献
424.
利用结构矩阵分析的方法得到了一类拟单生过程在离散情形时普通遍历、Ⅰ遍历和几何遍历的关系,并利用得到的结论对排队论中的一类问题作了处理,因而具有理论和实际应用的价值。 相似文献
425.
针对协同设计网格中油料装备模块化协同设计主体资源规范化表达问题,提出按照模块设计能力划分油料装备模块化协同设计主体资源的分类体系,给出油料装备模块化协同设计主体资源的信息描述模型。在此基础上,采用元数据完成了油料装备模块化协同设计主体资源描述的元数据集的定义,并采用可扩展的资源描述框架RDF实现了元数据集的描述,规范了具有值域要求属性的赋值空间,给出了基于元数据集的油料装备模块化协同设计主体资源的RDF描述方法,解决了协同设计网格中统一完整和无二义性地描述资源对象的问题,并提出了利用资源表达向导的策略,规范和简化了资源主体的资源表达。 相似文献
426.
Lipschitz非线性系统状态观测器设计新方法 总被引:1,自引:1,他引:0
针对Lipschitz非线性系统状态观测器,提出了一种以极小化条件数为目标准则的新的设计方法。运用梯度下降法和Slyvester方程,计算极小化条件数,优化增益矩阵和最大允许Lipschitz常数,完成观测器设计。通过同其它文献的算例比较,结果发现按文中方法设计的观测器具有迭代次数少、优化结果好的特点。 相似文献
427.
428.
We consider a supply chain in which a retailer faces a stochastic demand, incurs backorder and inventory holding costs and uses a periodic review system to place orders from a manufacturer. The manufacturer must fill the entire order. The manufacturer incurs costs of overtime and undertime if the order deviates from the planned production capacity. We determine the optimal capacity for the manufacturer in case there is no coordination with the retailer as well as in case there is full coordination with the retailer. When there is no coordination the optimal capacity for the manufacturer is found by solving a newsvendor problem. When there is coordination, we present a dynamic programming formulation and establish that the optimal ordering policy for the retailer is characterized by two parameters. The optimal coordinated capacity for the manufacturer can then be obtained by solving a nonlinear programming problem. We present an efficient exact algorithm and a heuristic algorithm for computing the manufacturer's capacity. We discuss the impact of coordination on the supply chain cost as well as on the manufacturer's capacity. We also identify the situations in which coordination is most beneficial. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
429.
Whereas much of the previous research in complex systems has focused on emergent properties resulting from self‐organization of the individual agents that make up the system, this article studies one vital role of central organization. In particular, four factors are conjectured to be key in determining the optimal amount of central control. To validate this hypothesis, these factors are represented as controllable parameters in a mathematical model. For different combinations of parameter values, the optimal amount of central control is found, either analytically or by computer simulation. The model is shown to provide results that match well with the level of control found across a broad spectrum of specific complex systems. This model also provides general guidelines as to how combinations of these factors affect the desirable level of control and specific guidelines for selecting and evaluating leaders. These results indicate that all of these factors, though not exhaustive, should be considered carefully when attempting to determine the amount of control that is best for a system. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
430.
在高精度伪码测距系统中,高功率放大器(HPA)是信号发射链路的重要组成部分,HPA会对发射信号引入非线性失真,进而恶化系统的伪码测距性能.通过理论推导和数值分析的方法,研究HPA的非线性特性对高精度伪码测距误差的影响,给出非线性放大条件下,伪码跟踪误差与放大器类型、放大器输出回退(OBO)、扩频码形参数等的定量关系.研究结果对工程上HPA的选择、功率余量的保留、基带扩频码形的设计等具有重要的参考价值. 相似文献