A produce‐to‐stock system with advance demand information and secondary customers

We consider a manufacturer (i.e., a capacitated supplier) that produces to stock and has two classes of customers. The primary customer places orders at regular intervals of time for a random quantity, while the secondary customers request a single item at random times. At a predetermined time the manufacturer receives advance demand information regarding the order size of the primary customer. If the manufacturer is not able to fill the primary customer's demand, there is a penalty. On the other hand, serving the secondary customers results in additional profit; however, the manufacturer can refuse to serve the secondary customers in order to reserve inventory for the primary customer. We characterize the manufacturer's optimal production and stock reservation policies that maximize the manufacturer's discounted profit and the average profit per unit time. We show that these policies are threshold‐type policies, and these thresholds are monotone with respect to the primary customer's order size. Using a numerical study we provide insights into how the value of information is affected by the relative demand size of the primary and secondary customers. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

大学生实践能力提升与创新意识培养的实践研究——以石河子大学实施大学生研究训练计划(SRP)为例

大学生作为高校的主体,是未来社会发展的主力军。如何把学生培养成具备创新意识、实践能力强、能适应社会需要的高素质人才是一直困惑当前高校本科教学的一个难题。结合我校本科教学中大学生研究训练计划(SRP)的开展现状,就提升大学生实践能力与培养学生的创新意识,做了初步的思考与探索。     

Exact algorithms for integrated facility location and production planning problems

We consider a class of facility location problems with a time dimension, which requires assigning every customer to a supply facility in each of a finite number of periods. Each facility must meet all assigned customer demand in every period at a minimum cost via its production and inventory decisions. We provide exact branch‐and‐price algorithms for this class of problems and several important variants. The corresponding pricing problem takes the form of an interesting class of production planning and order selection problems. This problem class requires selecting a set of orders that maximizes profit, defined as the revenue from selected orders minus production‐planning‐related costs incurred in fulfilling the selected orders. We provide polynomial‐time dynamic programming algorithms for this class of pricing problems, as well as for generalizations thereof. Computational testing indicates the advantage of our branch‐and‐price algorithm over various approaches that use commercial software packages. These tests also highlight the significant cost savings possible from integrating location with production and inventory decisions and demonstrate that the problem is rather insensitive to forecast errors associated with the demand streams. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

A note on necessary and sufficient conditions for ordering properties of coherent systems with exchangeable components

We give necessary and sufficient conditions based on signatures to obtain distribution‐free stochastic ordering properties for coherent systems with exchangeable components. Specifically, we consider the stochastic, the hazard (failure) rate, the reversed hazard rate, and the likelihood ratio orders. We apply these results to obtain stochastic ordering properties for all the coherent systems with five or less exchangeable components. Our results extend some preceding results. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

梯格形自适应控制

本文讨论并解决了具有d步时延的多变量系统的梯格形自适应控制问题。为此,把自适应控制下的闭环系统嵌入到ARMA模型中,采用梯格算法进行预报。为了考虑d步时延控制系统,采用简捷方法推导了d步梯格预报公式,并给出了控制量的确定方法。采用梯格形自适应控制可方便地调节模型的阶次,从而可以克服对象阶次不准引起的自适应控制失效的问题。     

潜艇近水面定深航行时的变结构控制方法研究

用自由递阶的变结构控制（ＶＳＣ）方法研究了在二阶波浪力干扰下,潜艇近水面航行时的定深控制问题,并分析了各控制参数对控制性能的影响。通过与ＰＩＤ控制方法的比较,表明本文设计的变结构控制系统具有较高的控制精度和较强的适应性。     

火炮射表数据处理程序及使用说明

在文献［１－４］的基础上,给出火炮射表数据处理用ＴｒｕｅＢＡＳＩＣＣｏｍｐｉｌｅｒ实现的程序清单和与之相关的使用说明。并介绍该程序的组成、设计特点、主要变量和使用注意事项,以及数据文件的命名法。另外还详细讨论了程序故障诊断及维护问题。     

电磁场式头盔瞄准系统计算机提高实时性能问题

头盔瞄准系统是一种时分制的电磁场探测方法。在这种方法中有个非常关键的问题是实时性能问题。该文对控制电磁场的发射、接收以及实时滤波提出了一种独特的软件编排方法,这种方法已取得了较明显的效果;该文还探讨了从计算机硬件编排上进行改进的设想,以期获得更好的实时性能。     

熵、信息、控制与系统的组织化程度

本文首先通过分析与推演导出了描述熵、信息与系统的组织化程度之间联系的几个基本关系式;然后据之分析指出,人类的意识行为,是高度有序的主体向有序度较低的对象系统输入信息、减少其熵、提高有序度从而使其得到同化或改造的过程;最后,利用上述结论剖析了系统工程方法论的合理性与有效性。     

一类二阶奇异Hamiltonian系统的非碰撞解

运用变分原理,拓扑度理论以及微局部分析技巧相结合的方法,作者讨论了一类二阶奇异Hamiltonian系统的时滞周期解之存在性。