A stochastic machine maintenance and sale problem: Results with different production functions

In this article we solve and analyze a stochastic version of the Boiteux problem by employing the stochastic optimal control method. Our setup is close to that of Thompson [22]. Our focus is to analyze, under the same structure, how different production functions and how the variance in machine deterioration/maintenance affect our optimal machine maintenance and sale date decisions. © 1993 John Wiley & Sons, Inc.     

Parallel machine scheduling with batch deliveries to minimize total flow time and delivery cost

Motivated by the flow of products in the iron and steel industry, we study an identical and parallel machine scheduling problem with batch deliveries, where jobs finished on the parallel machines are delivered to customers in batches. Each delivery batch has a capacity and incurs a cost. The objective is to find a coordinated production and delivery schedule that minimizes the total flow time of jobs plus the total delivery cost. This problem is an extension of the problem considered by Hall and Potts, Ann Oper Res 135 (2005) 41–64, who studied a two‐machine problem with an unbounded number of transporters and unbounded delivery capacity. We first provide a dynamic programming algorithm to solve a special case with a given job assignment to the machines. A heuristic algorithm is then presented for the general problem, and its worst‐case performance ratio is analyzed. The computational results show that the heuristic algorithm can generate near‐optimal solutions. Finally, we offer a fully polynomial‐time approximation scheme for a fixed number of machines. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 492–502, 2016     

Stepwise inspection in Bayesian multiattribute acceptance sampling

Bayesian models for multiattribute acceptance sampling have been developed under the assumption that sampling inspection is carried to completion. A Bayesian multiattribute model for stepwise sampling inspection is proposed, whereby sampling inspection is terminated as soon as the disposition of the inspection lot is determined. An iterative solution procedure is developed for obtaining optimal or near-optimal multiattribute acceptance sampling plans under stepwise sampling inspection. The effect of stepwise sampling inspection on the characteristics of an optimal sampling plan is investigated. It is shown that stepwise sampling inspection achieves a sampling plan with lower total expected cost than complete sampling inspection. In addition, it is shown that the sequence of attributes in a stepwise sampling inspection substantially affects the sampling plan and resultant expected cost. The proposed methodology is used to evaluate various heuristics which may be used to determine the sequence of attributes in a stepwise inspection procedure.     

柔性加工单元故障诊断的模糊Petri网模型

针对故障诊断专家系统中专家知识的模糊性和不确定性,给出用模糊Ｐｅｔｒｉ网（ＦＰＮ）模型表示模糊产生式规则（ＦＰＲ）知识的方法、知识的存储、模糊推理机制及算法的实现。同时,以ＪＣＳ—０２０（ＦＡＮＵＣ）加工中心主轴伺服故障诊断为例,说明该方法在故障诊断专家系统（ＦＤＥＳ）中应用的可行性与有效性。     

Statistical equivalency and optimality of simple step‐stress accelerated test plans for the exponential distribution

Accelerated life testing (ALT) is commonly used to obtain reliability information about a product in a timely manner. Several stress loading designs have been proposed and recent research interests have emerged concerning the development of equivalent ALT plans. Step‐stress ALT (SSALT) is one of the most commonly used stress loadings because it usually shortens the test duration and reduces the number of required test units. This article considers two fundamental questions when designing a SSALT and provides formal proofs in answer to each. Namely: (1) can a simple SSALT be designed so that it is equivalent to other stress loading designs? (2) when optimizing a multilevel SSALT, does it degenerate to a simple SSALT plan? The answers to both queries, under certain reasonable model assumptions, are shown to be a qualified YES. In addition, we provide an argument to support the rationale of a common practice in designing a SSALT, that is, setting the higher stress level as high as possible in a SSALT plan. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013     

亲合层析SELEX法筛选相思子毒素寡核苷酸适配子

报道了采用亲和树脂法对相思子毒素蛋白进行反复的SELEX筛选,获得与靶物质结合率这32．5％的富集文库,并克隆得到了单克隆适配子序列,软件模拟了这些序列的二级结构,选择部分序列选择性剪切后利用荧光偏振方法进行检测,对靶蛋白的检测限达到亚nmol量。     

试论20世纪20年代中国留苏军事教育与中国革命

20世纪20年代中国的留苏教育不仅为中国培养了革命干部,而且为中国共产党造就了一批军事人才。以往人们对前者关注较多,而对后者注意甚少。本文试图探讨20世纪20年代留苏军事教育的发展过程及其与中国国内革命形势的关系和对后来中国革命的影响。     

信息化条件下美军心理战"云"活动范式论

近年来,美军利用其先进的信息传输系统,综合运用信息媒介、人际关系、组织机构、生理刺激等多种方式,使心理战趋向系统整合的"云"活动.该种活动范式呈现出心理战主体构成复合化、心理战情报获取渠道网栅化、心理战信息开发系统化、心理战致效路径组合化、心理战作战空间多域化等特点.     

解非线性振动问题的摄动谐波平衡法

本文在谐波平衡法的基础上,引进摄动的思想,得出了用解析法解非线性振动问题的一个新的有效方法——摄动谐波平衡法。该方法无需对解的形式及谐波系数的量级预先有所了解,这是谐波平衡法所不能比拟的。另外,该方法使非线性振动问题的求解过程变得简单,只涉及解线性代数方程的运算,不必求解微分方程,这又比Lindstedt-Poincare方法、多尺度方法优越。     

瞬态激振法在测定超高精度车床主轴系统动态特性中的应用

瞬态激励试验是获得机械系统动态参数的重要方法之一。本文应用瞬态激振法对S1—235超高精度车床的主轴系统进行了动态试验,介绍了瞬态激励法的试验技术、基本原理和信号处理特点,测定了系统的固有频率、阻尼系数和动刚度。并通过Levy曲线拟合方法获得了系统的传递函数。