中国特色网络文化建设与大学生思想政治教育

随着网络技术的发展,网络文化也运用而生。网络文化的双面效应给高校的思想政治教育工作带来了新的挑战。本文在分析网络文化对大学生影响的基础上,提出构建中国特色的网络文化,推进大学生思想政治教育的思路和措施。     

铝合金表面涂覆隐身吸波涂层脱落原因分析

通过对某装备车体外脱落隐身吸波涂层样品的表面形貌、截面形貌、元素组成及含量分析,发现吸波涂层和Al2O3钝化层之间没有化学结合键,只存在物理吸附和机械结合,在外部环境的作用下,很容易引起隐身吸波涂层的脱落。     

弹炮结合武器系统综合效能评估指标体系

效能评估指标体系是弹炮结合系统综合效能评估的基础环节.首先,通过对弹炮结合系统参数结构模型的分析,探讨综合效能评估指标体系的设计原则,并提出弹炮结合系统综合效能评估指标的基本结构和体系;接着,在此基础上建立弹炮结合系统综合效能评估的模型指标框架.分析表明,该指标体系框架为弹炮结合系统的综合效能评估奠定了基础.     

基于ADC的炮兵激光观测仪侦察效能分析

运用了效能分析方法,针对复杂战场环境下炮兵侦察系统的效能进行分析,特别是炮兵激光观测仪,揭示其内在规律,为提高现有侦察装备的作战效能找到重要途径,也为指挥员的决策提供可靠的战略支持.在侦察系统效能分析理论的基础上,对典型的激光观测仪侦察装备进行了计算评估验证,其方法和成果可供其他武器系统效能评估时借鉴参考.     

Designing and pricing menus of extended warranty contracts

Extended warranties provide “piece of mind” to a consumer in that product failures which occur after the base warranty expires are rectified at little or no cost. They also provide an additional source of revenue for manufacturers or third‐party providers, such as retailers or insurance providers, and help cultivate consumer loyalty. In this article, we analyze a number of extended warranty contracts which differ in design, including restrictions on deferrals and renewals. With the use of dynamic programming, we compute the optimal strategy for a consumer with perfect information and determine the optimal pricing policy for the provider given the consumer's risk characterization. We also provide insight into when different contracts should be issued. Finally, we illustrate how profits can be dramatically increased by offering menus of warranty contracts, as opposed to stand alone contracts, with the use of integer programming. Surprisingly, risk‐taking consumers provide the greatest benefit to offering menus. These insights can help a company develop a comprehensive warranty planning strategy for given products or product lines. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009     

基于中位秩的动态可靠性增长模型

给出了一种动态可靠性增长模型。首先利用统计中的中位秩法结合试验数据确定各个增长阶段的失效率 ,这一技术可以很好地解决小子样问题 ,并且由于利用了动态建模的思想 ,因而可以客观地反映系统的实际状态。其次 ,该模型继承了传统Duane模型简单、直观、易于进行参数估计的优点 ,同时又很好地处理了传统Duane模型所不适用的分阶段、多场景试验的情形 ,因而有很广阔的工程应用前景。最后通过仿真实例验证了该模型的正确性     

防空导弹总体设计方法的新发展——弹族化设计

研究了防空导弹一种新的总体设计思想———弹族化设计 ,论述了防空导弹弹族的设计与研制采用预先计划的产品改进P3 I(Pre PlannedProductImprovement)系统方法的必要性与有效性 ,通过对一个覆盖全空域、包含有 3种导弹的防空导弹弹族进行一体化优化设计 ,其结果证明了弹族化设计方法的可行性和优越性     

Estimating failure time distribution and its parameters based on intermediate data from a Wiener degradation model

Instead of measuring a Wiener degradation or performance process at predetermined time points to track degradation or performance of a product for estimating its lifetime, we propose to obtain the first‐passage times of the process over certain nonfailure thresholds. Based on only these intermediate data, we obtain the uniformly minimum variance unbiased estimator and uniformly most accurate confidence interval for the mean lifetime. For estimating the lifetime distribution function, we propose a modified maximum likelihood estimator and a new estimator and prove that, by increasing the sample size of the intermediate data, these estimators and the above‐mentioned estimator of the mean lifetime can achieve the same levels of accuracy as the estimators assuming one has failure times. Thus, our method of using only intermediate data is useful for highly reliable products when their failure times are difficult to obtain. Furthermore, we show that the proposed new estimator of the lifetime distribution function is more accurate than the standard and modified maximum likelihood estimators. We also obtain approximate confidence intervals for the lifetime distribution function and its percentiles. Finally, we use light‐emitting diodes as an example to illustrate our method and demonstrate how to validate the Wiener assumption during the testing. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

考虑载荷作用次数的多失效模式扭力轴灵敏度分析

机械构件的不同的失效模式之间具有一定的相关性,而且随机载荷作用次数对机械构件的可靠性有一定程度的影响。因此对机械构件进行可靠性灵敏度分析时,需要充分考虑其不同失效模式和载荷作用次数的影响。通过运用顺序统计量理论考虑载荷多次作用以及多种失效模式条件下机械构件可靠性及可靠性灵敏度的变化规律,运用随机摄动理论和四阶矩技术,建立一种考虑载荷作用次数的多失效模式机械构件可靠性灵敏度分析数值方法的应力强度干涉模型。在随机变量前四阶矩已知的情况下,结合灵敏度分析的梯度算法,推导出关于随机变量均值和方差的灵敏度计算公式。以某履带车辆底盘扭力轴为例进行计算,得到其可靠度随载荷作用次数、随机变量均值和方差而改变的可靠性灵敏度变化曲线,为扭力轴的可靠性优化提供一定的理论依据。研究成果可以推广到相关机械可靠性灵敏度设计和结构优化领域,具有非常重要的实用意义。     

E级超级计算机故障预测的数据采集方法

面向未来E级超级计算机,提出用于故障预测的数据采集框架,能够全面采集与计算结点故障相关的状态数据。采用自适应多层分组数据汇集方法,有效解决随着系统规模增长数据汇集过程开销过大的问题。在TH-1A超级计算机上的实现和测试表明,该数据采集框架具有开销小、扩展性好的优点,能够满足未来大规模系统故障预测数据采集的需求。