A m‐parallel crane scheduling problem with a non‐crossing constraint

In this paper, we study a m‐parallel machine scheduling problem with a non‐crossing constraint motivated by crane scheduling in ports. We decompose the problem to allow time allocations to be determined once crane assignments are known and construct a backtracking search scheme that manipulates domain reduction and pruning strategies. Simple approximation heuristics are developed, one of which guarantees solutions to be at most two times the optimum. For large‐scale problems, a simulated annealing heuristic that uses random neighborhood generation is provided. Computational experiments are conducted to test the algorithms. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007.     

Stein–Chen approximation and error bounds for order fill rates in assemble‐to‐order systems

Assemble‐to‐order (ATO) is an important operational strategy for manufacturing firms to achieve quick response to customer orders while keeping low finished good inventories. This strategy has been successfully used not only by manufacturers (e.g., Dell, IBM) but also by retailers (e.g., Amazon.com). The evaluation of order‐based performance is known to be an important but difficult task, and the existing literature has been mainly focused on stochastic comparison to obtain performance bounds. In this article, we develop an extremely simple Stein–Chen approximation as well as its error‐bound for order‐based fill rate for a multiproduct multicomponent ATO system with random leadtimes to replenish components. This approximation gives an expression for order‐based fill rate in terms of component‐based fill rates. The approximation has the property that the higher the component replenishment leadtime variability, the smaller the error bound. The result allows an operations manager to analyze the improvement in order‐based fill rates when the base‐stock level for any component changes. Numerical studies demonstrate that the approximation performs well, especially when the demand processes of different components are highly correlated; when the components have high base‐stock levels; or when the component replenishment leadtimes have high variability. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012     

基于规则控制的快速高度跟踪算法

提出一种全新的基于模糊推理与规则控制的高度跟踪算法。这种算法无论是在跟踪效果与运算速度上都大大优于以往的最速下降法、动态规划法、最优控制法等,而且可以对最大俯仰角、最大可用过载、希望跟踪程度等跟踪参数进行随意设定。大量的仿真计算证明,该算法具有很好的实时性、收敛性及可扩展性。可以极大地减轻对地攻击低空轨迹规划的工作,对巡航导弹、无人机更具应用价值     

Scheduling stochastic jobs with asymmetric earliness and tardiness penalties

We consider a stochastic counterpart of the well-known earliness-tardiness scheduling problem with a common due date, in which n stochastic jobs are to be processed on a single machine. The processing times of the jobs are independent and normally distributed random variables with known means and known variances that are proportional to the means. The due dates of the jobs are random variables following a common probability distribution. The objective is to minimize the expectation of a weighted combination of the earliness penalty, the tardiness penalty, and the flow-time penalty. One of our main results is that an optimal sequence for the problem must be V-shaped with respect to the mean processing times. Other characterizations of the optimal solution are also established. Two algorithms are proposed, which can generate optimal or near-optimal solutions in pseudopolynomial time. The proposed algorithms are also extended to problems where processing times do not satisfy the assumption in the model above, and are evaluated when processing times follow different probability distributions, including general normal (without the proportional relation between variances and means), uniform, Laplace, and exponential. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44, 531–557, 1997.     

推进军队政治工作信息化建设的几点思考

政治工作信息化建设是加快军队现代化建设的客观需要,又是充分发挥政治工作服务保障作用的必然要求。必须充分认清军队政治工作信息化面临的形势任务,加快建设步伐。要抓住关键,把握政治工作信息化建设的宏观思路;突出重点,打牢政治工作信息化建设的基础;采取有效措施,确保政治工作信息化建设的跨越式发展。     

应用Origin剔除弹药实验数据中的异常值

提出了一种应用肖维勒（Chauvenet）准则和Origin数据分析软件剔除弹药实验数据异常值的方法。     

国内控制系统故障诊断技术的现状与展望

介绍了国内控制系统故障诊断技术的发展情况,对其各种方法进行了详细的评述,给出其应用总结,最后对其发展进行了展望。     

重庆滨江空间的城市可识别性作用

在城市趋同发展的今天,营造城市特色空间以提高城市可识别性显得尤为重要。以重庆滨江空间为研究对象,通过文献查阅和实地调研归纳了重庆滨江空间的发展历程;分析了重庆滨江空间的特征,以及滨江空间对城市可识别性的重要作用;提出了重庆滨江空间多层次的生态环境丰富了城市公共生活,是辨析城市结构的重要场所,影响着城市发展进程中文脉传承的观点。     

攻击型无人机巡弋搜索航路优化设计与仿真

为改进攻击型无人机待机段的飞行搜索性能,应用以最大值原理为基础的最优搜索理论对无人机待机搜索路线进行研究,得出光栅式、螺旋式和扫雪式三种搜索路线,并通过计算机仿真与传统的8字式搜索方式进行了比较.仿真结果表明,优化设计结果是合理的,证实了其有效性和可行性.     

DSP实现坦克火控系统弹道微分方程数值算法

针对现役坦克火控系统弹道解算广泛采用的逼近法的缺点和不足,提出了改进后的弹道微分方程直接数值解算算法,以数字信号处理器(DSP)作为该算法的硬件实现环境进行了实验。结果表明,以DSP技术为基础的改进弹道微分方程解算算法解决了逼近法的不足。解算速度快,精度高。这说明该算法在坦克火控系统应用中具有良好的发展前景。