装甲车辆使用与保障费用的指数回归模型

运用逐步回归和主成分分析的方法,选取了装甲车辆诸多战技性能指标集合中的自变量子集,建立了该子集与使用与保障费用之间指数回归方程组.该模型也可推广应用于装甲车辆综合性能的评估.     

培养学生数学思维的方法和途径

数学思维是以数学问题为载体，通过提出问题、解决问题的形式，达到对数学模式结构的本质的一般性认识的思维过程。认真分析数学思维的类型及其特点，培养数学思维的方法。     

Estimating component characteristics from system failure‐time data

Suppose that failure times are available from a random sample of N systems of a given, fixed design with components which have i.i.d. lifetimes distributed according to a common distribution F. The inverse problem of estimating F from data on observed system lifetimes is considered. Using the known relationship between the system and component lifetime distributions via signature and domination theory, the nonparametric maximum likelihood estimator _N(t) of the component survival function (t) is identified and shown to be accessible numerically in any application of interest. The asymptotic distribution of _N(t) is also identified, facilitating the construction of approximate confidence intervals for (t) for N sufficiently large. Simulation results for samples of size N = 50 and N = 100 for a collection of five parametric lifetime models demonstrate the utility of the recommended estimator. Possible extensions beyond the i.i.d. framework are discussed in the concluding section. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

基于主成分分析的战场目标选择模型

针对战场目标数量众多、信息复杂的特点,运用主成分分析理论探讨了战场目标选择问题.分析了战场目标的组成.确立了目标重要性评价指标体系,建立了战场目标重要性评估模型.对某作战想定t时刻战场目标的重要性进行了综合评估,得到了战场目标排列顺序.该模型克服了指标权重选择上主观因素的影响,便于计算机编程迅速实现,较好地满足了指挥员快速准确把握打击重心,确立打击次序的需求.     

网络化指挥信息系统建设的软件构件技术

研究了基于构件技术建设网络化指挥信息系统的方法,以适应随需应变和快速开发这一新的作战要求。给出了框架、构件、扩展点等基本概念,提出了基于构件的指控系统框架、业务流程、系统重组方法,讨论了通用构件模型、共享信息模型、流程控制、构件获取和数据服务机制等系统建设的关键技术,探讨了指挥控制信息系统的建设途径,为发展未来指挥控制信息系统的建设提出了一种新思路。     

核独立分量分析的随机滤波剩余寿命预测模型

基于随机滤波的预测模型是剩余寿命预测方法的一个重要分支,当前制约滤波模型的一个重要问题就是如何对大量高维非线性状态监测数据进行特征降维,以易于模型参数求解.通过线性回归处理了非定期换油保养对油液数据的影响;运用核独立分量分析进行特征降维,消除了各维数据之间相关性对模型预测精度的影响;建立了基于油液增量的滤波模型,并设计了极大似然估计方法求解模型参数;最后实例验证了模型的有效性和实用性.     

Country survey XVII: New zealand's defence policy

New Zealand's current defence strategy, first expressed in NZ Government (1991), is one of "self-reliance in partnership". We outline the country's defence policy in historical context, examine its current defence expenditure and capabilities, and document the genesis of recent major changes in security policy. We pay particular attention to the role of explicit economic analysis and advice in the formation of these policy changes.     

金属类MEMS器件可靠性试验技术研究

针对金属类MEMS机构可靠性水平较低且没有标准化的可靠性试验方法的现状,提出将强化试验方法引入金属类MEMS机构的可靠性研究中．确定强化试验的内容为温度循环、随机振动和冲击试验,并分别设计试验剖面．选取MEMS惯性开关作为典型器件开展试验研究,试验结果表明,所设计的可靠性试验能够有效激发MEMS机构的潜在缺陷,温度应力易引起MEMS器件层间产生疲劳效应,而振动和冲击应力则易引发器件结构性损坏;环境应力对MEMS机构具有疲劳累积效应,经历较多试验类型的样本较经历较少试验类型的样本更容易失效;惯性开关的主要失效模式是分层和变形,这2种失效模式在金属类MEMS机构中具有代表性．     

Coping with shortages caused by disruptive events in automobile supply chains

Unpredictable disruptive events significantly increase the difficulty of the management of automobile supply chains. In this paper, we propose an automobile production planning problem with component chips substitution in a finite planning horizon. The shortage of one chip can be compensated by another chip of the same type with a higher-end feature at an additional cost. Therefore, the automobile manufacturer can divert the on-hand inventory of chips to product lines that are more profitable in the event of shortages caused by supply chain disruptions. To cope with this, we propose a max-min robust optimization model that captures the uncertain supplies of chips. We show that the robust model has a mixed-integer programming equivalence that can be solved by a commercial IP solver directly. We compare the max-min robust model with the corresponding deterministic and two-stage stochastic models for the same problem through extensive numerical experiments. The computational results show that the max-min robust model outperforms the other two models in terms of the average and worst-case profits.     

中红外光谱在润滑油分类识别中的应用

由中红外光谱能够获得不同种类润滑油的组成与结构信息.分别用聚类分析法和主成分分析法提取润滑油的中红外光谱信息,对齿轮油、内燃机油和液压油这3大类共113个润滑油样品进行了分类识别.采用系统聚类法对其进行分类,比较了不同类间距离、样品间距离和光谱区间对聚类分析结果的影响.采用主成分分析法对齿轮油、内燃机油、液压油及不同黏...