The selection allocation problem

The Selection Allocation Problem (SAP) is a single period decision problem which involves selecting profit‐maximizing (or cost‐minimizing) activities from various distinct groups, and determining the volume of those activities. The activities in each group are selected subject to the availability of that group's resource, which is provided by either pooling or blending raw inputs from several potential sources. Imbedded in the decision process is the additional task of determining how much raw input is to be allocated to each group to form the resource for that group. Instances of this problem can be found in many different areas, such as in tool selection for flexible manufacturing systems, facility location, and funding for social services. Our goal in this paper is to identify and exploit special structures in the (SAP) and use those structures to develop an efficient solution procedure. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 707–725, 1999     

Economic design of a two-stage control chart based on both performance and surrogate variables

The traditional approach to economic design of control charts is based on the assumption that a process is monitored using only a performance variable. If, however, the performance variable is costly to measure and a less expensive surrogate variable is available, the process may be more efficiently controlled by using both performance and surrogate variables. In this article we propose a model for economic design of a two-stage control chart which uses a highly correlated surrogate variable together with a performance variable. The process is assumed to be monitored by the surrogate variable until it signals out-of-control behavior, then by the performance variable until it signals out-of-control behavior or maintains in-control signals for a prespecified amount of time, and the two variables are used in alternating fashion. An algorithm based on the direct search method of Hooke and Jeeves [6] is used to find the optimum values of design parameters. The proposed model is applied to the end-closure welding process for nuclear fuel to compute the amount of reduction in cost compared with the current control procedure. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 958–977, 1999     

小子样方法在电子对抗仿真试验中的应用

小子样问题是武器装备试验必须解决的客观问题,实现小子样试验是武器装备试验追求的最高境界.仿真试验作为武器装备试验的一种手段,以其可重复、大容量等不可比拟的优势,受到有关专家的高度重视.首先从武器装备试验实际需求出发,阐述了小子样问题在仿真试验中的意义及其实现途径,最后给出了正交设计法在某型雷达侦察机仿真试验中的应用实例.通过与常规试验方法相比,其提高试验效率6倍多,试验结果分析也更科学合理,军事经济效益明显.     

某超限高层建筑结构分析与优化

为有效控制平、立面超限高层结构的扭转效应,利用结构概念设计和程序计算分析,较为详细地介绍了一栋因建筑平面为蝶型而平面规则性超限的高层建筑进行结构分析和结构优化的全过程。通过调整结构平面布置、计算分析和设置适当的构造措施,使结构整体设计既满足了建筑功能的需要,又符合现行规范的要求,计算结果也证实了这一结论。该设计可供类似工程参考。     

Responses of HFR-LWC beams under close-range blast loadings accompanying membrane action

The load-carrying capacities and failure patterns of reinforced concrete components can be significantly changed by membrane effects. However, limited work has been carried out to investigate the blast resistance of Hybrid Fiber Reinforced Lightweight Aggregate Concrete (HFR-LWC) members accompanying membrane action. This paper presents a theoretical approach to quantitatively depicting the membrane behavior and its contribution on the behavior of HFR-LWC beams under close-range blast loadings, and the suitability of the proposed model is validated by a series of field tests. An improved Single-Degree-of-Freedom (SDOF) model was employed to describe the dynamic responses of beam-like members under blast loadings accompanying membrane action, where the mass-load coefficient is determined according to the nonuniformly distributed load induced by close-range explosion, and the membrane action is characterized by an in-plane (longitudinal) force and a resisting moment. The elasto-plastic and recovery responses of HFR-LWC beams under the combined action of blast load and membrane force were analyzed by the promoted model. A specially built end-constrain clamp was developed to provide membrane action for the beam member when they are subjected to blast load simultaneously. It is demonstrated that the analytical displacement-time histories are in good agreement with experimental results before peak deflections and that the improved SDOF model is an acceptable tool for predicting the behavior of HFR-LWC beams under blast loadings accompanying membrane action.     

基于仿真推演的导弹作战实验框架分析与设计

针对导弹武器论证设计高成本、高复杂度的问题,本文梳理了导弹作战实验设计服务的多种功能需求,阐述了导弹作战实验设计的数理方法;为构建具有较好柔性的导弹作战实验仿真框架,针对导弹系统多个性能指标,辨析了各类导弹作战实验仿真变量;针对作战实验中的环境和装备特性,梳理了导弹作战实验模型体系,提出了仿真新模型开发框架;结合导弹作战实验案例,构建了实验设计优化方法,提出了作战实验检验设计方案;从运行实验出发,阐述了设定作战想定、建立控制机制、开展结果分析等仿真环节的具体设计。通过这些工作,形成了一种支撑导弹作战实验的柔性仿真框架,为进一步开展基于仿真推演的导弹作战实验提供参考。     

飞行器有源对消隐身技术

隐身技术已经成为现代高性能飞行器设计的重要支撑,是先进战机的基本要求。现行的隐身设计方法主要包括气动外形优化以及隐身材料涂覆。随着雷达探测能力的不断提升,尤其在米波雷达探测背景下,外形优化与隐身涂层变得不再有效,有源隐身技术被重新予以重视并有望成为新的隐身技术突破点。本文着重分析了有源对消技术的基本概念、技术现状以及相应的关键技术,对该技术体制的优势和特点进行了归纳和总结。     

数据基故障诊断算法更新问题研究

机内测试被广泛应用于故障诊断、装备健康管理与预测等领域。针对机内测试设备在设计和升级时遇到的分类器更新、样本数量不平衡、硬件条件限制问题,提出初步解决方案。利用基于密度的聚类和人工免疫方法处理原始数据;提出基于代表样本点的混合学习方法;利用支持向量机和仿真案例验证所提方法。结果表明所提方法能够解决上述问题,有助于基于数据的机内测试设备设计与升级。     

Global planning of accelerated degradation tests based on exponential dispersion degradation models

The accelerated degradation test (ADT) is an efficient tool for assessing the lifetime information of highly reliable products. However, conducting an ADT is very expensive. Therefore, how to conduct a cost-constrained ADT plan is a great challenging issue for reliability analysts. By taking the experimental cost into consideration, this paper proposes a semi-analytical procedure to determine the total sample size, testing stress levels, the measurement frequencies, and the number of measurements (within a degradation path) globally under a class of exponential dispersion degradation models. The proposed method is also extended to determine the global planning of a three-level compromise plan. The advantage of the proposed method not only provides better design insights for conducting an ADT plan, but also provides an efficient algorithm to obtain a cost-constrained ADT plan, compared with conventional optimal plans by grid search algorithms.     

激光制备高附着性能的铜基类金刚石膜

提升类金刚石(Diamond-Like Carbon, DLC)膜在被保护基底上的附着能力具有明显的实际应用价值。从微观机理上分析了前期设计的Cu基多层DLC膜有效性的原因。在此基础上,研究了DLC/SiC循环层中两者厚度比例对膜层的附着性能、纳米硬度和耐磨性的影响,以优化结构、进一步提升实际应用所需的膜层性能。纳米划痕和压痕测试结果表明:随着DLC层与SiC层厚度比例的增大,多层DLC膜在Cu基上附着性能逐渐降低,但当厚度比小于2.3时,仍接近厚度400 nm的单层DLC膜在Si基上的附着性能;Cu基多层DLC膜的纳米硬度逐渐提高,同时,耐磨性接近纯DLC膜。