相关维经典计算方法的修正

通过对洛伦兹 (Lorenz)方程生成的混沌奇怪吸引子的分析计算 ,指出了相关维经典计算方法中存在的问题 ,进行了修正改进     

FRC/钢嵌入式T型接头疲劳试验及可靠性分析

为了研究FRC/钢嵌入式T型连接接头疲劳特性,采用真空成型工艺(VARTM)及缝合技术制作T型连接接头,利用Letry疲劳试验机对接头开展拉-拉疲劳试验。根据疲劳试验结果,研究了T型接头在拉-拉疲劳载荷作用下初始损伤特性及损伤演变规律;基于两参数Weibull分布模型,开展T型连接接头疲劳可靠性分析,拟合得到接头在不同应力水平下的疲劳寿命分布规律,给出接头在不同应力水平下疲劳可靠度函数,以及接头在指定可靠度下应力/寿命双对数曲线关系式(R-lnS-lnN曲线)。结果表明,ln ln[1/R(N)]与lnN呈现良好的线性关系,T型接头疲劳寿命服从Weibull分布;疲劳寿命可靠度双对数方程建立了可靠度、疲劳寿命以及疲劳应力的关系,可指导接头疲劳可靠性设计和工程应用。     

Measures of component importance for markov chain imbeddable reliability structures

In this article we study the reliability importance of the components for the wide class of Markov chain imbeddable systems (MIS). Methods for the evaluation of Birnbaum importance are developed for a general MIS, and some generating function techniques are demonstrated for the special case of homogeneous MISs. As an application, the reliability ordering for the components of a k‐out‐of‐n and consecutive‐k‐out‐of‐n structure is examined in some detail. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 613–639, 1999     

基于Monte Carlo的军事物流结点可靠性评估方法

军事物流网络结点是构成军事物流网络的基本要素。战场环境瞬息万变,结点的可靠性往往受许多不确定因素的影响,计及不确定因素的评估方法可以更客观、真实地评估结点的可靠性。基于此,提出了刻画物流结点可靠性的评估指标体系,建立了计及不确定因素的军事物流结点可靠性评估模型,给出了Monte Carlo求解算法。对影响结点可靠性的因素进行了分析,在此基础上提出了改善军事物流结点可靠性的措施。以某战役级军事物流网络为例进行算例分析,验证了该方法的可行性和正确性。     

Present practices and future plans for MIL-STD-781

MIL-STD-781 specifies reliability acceptance test procedures based on both fixed-length tests and probability ratio sequential tests. The assumption underlying MIL-STD-781 is a constant mean time between failures (MTBF) and typical practice applies MIL-STD-781 to electrical, electronic, and mechanical equipment. This article discusses some of the difficulties that have prompted the C and D revisions of MIL-STD-781. In addition, it discusses the relationship of MIL-STD-781 with MIL-STD-1635(EC) which deals with reliability growth testing. The article concludes with a discussion of needed research in reliability growth testing, in support of MIL-STD-781, and in the area of stress and its impact of MTBF.     

主体间性视野下的师幼关系及实践策略

本文运用主体间性的教育哲学理论,通过对当前我国幼儿园师幼交往关系中教师与幼儿主体地位缺失的分析,以建立平等对话交流的师幼主体间性关系为目标,提出转变教育理念、加强幼儿教师的素质培养、开展差异性教学、给予幼儿更多理解和宽容的实践策略。     

路面不平度的频谱分析及其AR模型

描述了路面不平度的统计特性,建立了AR模型。运用现代谱估计的方法对沙土地、硬土地和耕地等非人工路面的频谱特性进行了分析,得到了沙土地等3种路面的加速度功率谱和位移功率谱密度曲线图。结果表明,沙土地和耕地路面要好于硬土地路面,该结论与常识相符,验证了用AR模型法进行功率谱分析的可靠性和可行性。     

流域变换的串行与并行策略研究

流域变换是数字形态学中用于图像分割的一种经典方法,其并行化问题成为近年来研究的重点。首先给出了流域变换的数学模型,并归纳列举了几种离散情况下的形式化定义;其次分类总结了近年来流域变换串行算法研究的新进展,从而在此基础上重点讨论了相应的并行化策略。详细分析了设计并行流域算法需要考虑的几个问题;并比较评价了现有并行算法的性能特点,得出了一些结论;最后提出了有待进一步研究的问题。     

Properties of an approximate hazard transform

The calculation of the exact reliability of complex systems is a difficult and tedious task. Consequently simple approximating techniques have great practical value. The hazard transform of a system is an invertible transformation of its reliability function which is convenient and useful in both applied and theoretical reliability work. A simple calculus for finding an approximate hazard transform for systems formed by series and parallel combinations of components is extended so that it can be used for any coherent system. The extended calculus is shown to lead to conservative approximations. A first order version of the extended calculus is also discussed. This method of approximation is even more simple to use, but is not always conservative. Examples of its application indicate that it is capable of giving quite accurate results.     

大学生消费行为调查分析及对策研究

目前大学生的消费意识、消费方式、消费观念已经在消费领域中显露出与已有经济收入的新富群体靠近的趋势,而这种超越自己学生身份的消费现象和观念值得关注和深思。文章通过分析S大学学生消费行为的现状,了解当前大学生消费中存在的具体问题,并提出了解决消费问题的主要对策和建议。     

基于相关性函数的多站微动特征分析与提取

针对多站雷达精度跨度大、难以有效进行融合识别的问题,提出了基于相关性函数的多站加权融合方法。首先建立了弹道目标滑动散射模型,通过时延相乘重构回波,并利用扩展Hough变换提取出距离像的曲线参数,从而建立方程组以求取微动信息。然后利用相关性函数对各雷达的支持度进行分析,最终对支持度高的观测数据进行融合识别。仿真结果表明该方法计算简单,能有效提高微动参数的估计精度,客观地反映各部雷达的可靠度。     

Inventory competition with yield reliability improvement

This article studies the inventory competition under yield uncertainty. Two firms with random yield compete for substitutable demand: If one firm suffers a stockout, which can be caused by yield failure, its unsatisfied customers may switch to its competitor. We first study the case in which two competing firms decide order quantities based on the exogenous reliability levels. The results from the traditional inventory competition are generalized to the case with yield uncertainty and we find that quantity and reliability can be complementary instruments in the competition. Furthermore, we allow the firms to endogenously improve their yield reliability before competing in quantity. We show that the reliability game is submodular under some assumptions. The results indicate that the competition in quantity can discourage the reliability improvement. With an extensive numerical study, we also demonstrate the robustness of our analytical results in more general settings. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 107–126, 2015     

武警总队军用土地利用结构合理性分析

以武警某总队为例,引入经济学中的洛伦茨曲线和基尼系数两种方法,对其进行军用土地利用结构分析,研究军用土地利用类型的分散或集中程度,判断其下辖单位的军用土地利用专门化程度,进而分析其合理性,对不合理之处给出相应的措施。并得出结论认为,运用以上两种方法所分析的结果一致,都能对军用土地利用结构进行分析,且相互补充。     

机构的工作能力储备及工作能力计算模型

机构工作能力的定量分析是研究机械产品可靠性的基础.提出了工作能力储备的概念,分析了工作能力储备与安全系数、约束条件参数及可靠度的关系.指出传统设计中采用安全系数来保证机械产品质量存在的缺点,进而给出机构工作能力的计算模型.为机构工作能力的定量描述奠定了基础.     

新疆城乡居民收入差距的关联分析——基于灰色关联理论

现阶段城乡居民收入差距不断扩大，这不仅影响社会公平，而且影响经济社会长期稳定的持续发展。本文以新疆为例，选取1978—2008年的统计数据，对新疆城乡居民收入差距的现状进行分析，并利用灰色关联理论分析影响新疆城乡居民收入差距的主要因素，据此提出缩小城乡收入差距的对策和建议。     

Inequality‐based reliability estimates for complex systems

Full‐system testing for large‐scale systems is often infeasible or very costly. Thus, when estimating system reliability, it is desirable to use a method that uses subsystem tests, which are often less expensive and more feasible. This article presents a method for bounding full‐system reliabilities based on subsystem tests and, if available, full‐system tests. The method does not require that subsystems be independent. It accounts for dependencies through the use of certain probability inequalities. The inequalities provide the basis for valid reliability calculations while not requiring independent subsystems or full‐system tests. The inequalities allow for test information on pairwise subsystem failure modes to be incorporated, thereby improving the bound on system reliability. We illustrate some of the properties of the estimates via an example application. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013     

A general approach to the shape of failure rate and MRL functions

Failure rate and mean residual life are two important characteristics for studying reliability of products. In literature, some work studied the shape of failure rate function based on the knowledge of the associated probability density function; some other work investigated the shape of mean residual life function based on the shape of the associated failure rate function separately for continuous case and discrete case. In this article, a general approach is developed which can be applied to the aforementioned studies. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004     

农村公共产品供给与农民增收的关联研究

目前我国城乡差距突出表现为公共产品差距,公共产品有效供给不足已成为当前制约农民增收的瓶颈。无论从理论分析还是从国内外实践看,公共产品的有效供给与农民的增收呈现正相关关系。因此,提高公共产品的有效供给是促进农民增收的有效途径,针对公共产品供给实践中存在的影响农民增收的问题而采取相应的对策是当前促进农民增收的理性选择。     

X射线衍射仪图谱的定量分析初探

在XD-2型X射线衍射仪分析软件的基础上,制作了Al2O3定量分析所用的内标曲线,并对混合物样品中的物相进行了定量分析,结果和配比值完全一致,说明这种定量分析方法均能运用于多相混合物中物相的定量分析     

税收与收入公平分配的正相关性探析

税收是国家调节收入公平分配的重要手段。税收的公平调节功能决定了其与收入公平分配的正相关关系。在税收实践中,要不断强化税收与收入公平分配的正相关关系,以更好地发挥税收的市场公平功能、社会公平功能和伦理公平功能,从而实现收入公平分配。