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1.
针对通用发控单元的维护需求和共架武器系统的训练需求,设计了通用筒弹模拟系统.该系统通过1553B总线与通用发控单元通信,实现了筒弹功能模拟和筒弹故障模拟.经测试,该系统运行稳定可靠,各项功能满足设计指标.  相似文献   
2.
Strengthening the United States' ability to prevent adversaries from smuggling nuclear materials into the country is a vital and ongoing issue. The prospect of additional countries, such as Iran, obtaining the know‐how and equipment to produce these special nuclear materials in the near future underscores the need for efficient and effective inspection policies at ports and border crossings. In addition, the reduction of defense and homeland security budgets in recent years has made it increasingly important to accomplish the interdiction mission with fewer funds. Addressing these complications, in this article, we present a novel two‐port interdiction model. We propose using prior inspection data as a low‐cost way of increasing overall interdiction performance. We provide insights into two primary questions: first, how should a decision maker at a domestic port use detection data from the foreign port to improve the overall detection capability? Second, what are potential limitations to the usefulness of prior inspection data—is it possible that using prior data actually harms decision making at the domestic port? We find that a boundary curve policy (BCP) that takes into account both foreign and domestic inspection data can provide a significant improvement in detection probability. This BCP also proves to be surprisingly robust, even if adversaries are able to infiltrate shipments during transit. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 433‐448, 2013  相似文献   
3.
文中论述了一种贮液圆柱壳动力特性的分析计算方法,分析了弹性壳和液体之间的相互耦合作用。假设贮液满足速度势理论,对于圆柱空壳采用有限元法计算其动能和应变能。采用这种方法,节点未知数数目远小于壳体和液体部分都采用有限元法时的节点未知数数目。  相似文献   
4.
Following work of Stroud and Saeger (Proceedings of ISI, Springer Verlag, New York, 2006) and Anand et al. (Proceedings of Computer, Communication and Control Technologies, 2003), we formulate a port of entry inspection sequencing task as a problem of finding an optimal binary decision tree for an appropriate Boolean decision function. We report on new algorithms for finding such optimal trees that are more efficient computationally than those presented by Stroud and Saeger and Anand et al. We achieve these efficiencies through a combination of specific numerical methods for finding optimal thresholds for sensor functions and two novel binary decision tree search algorithms that operate on a space of potentially acceptable binary decision trees. The improvements enable us to analyze substantially larger applications than was previously possible. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
5.
In this paper, we study the problem of scheduling quay cranes (QCs) at container terminals where incoming vessels have different ready times. The objective is to minimize the maximum relative tardiness of vessel departures. The problem can be formulated as a mixed integer linear programming (MILP) model of large size that is difficult to solve directly. We propose a heuristic decomposition approach to breakdown the problem into two smaller, linked models, the vessel‐level and the berth‐level models. With the same berth‐level model, two heuristic methods are developed using different vessel‐level models. Computational experiments show that the proposed approach is effective and efficient. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
6.
This article treats the problem of scheduling multiple cranes processing jobs along a line, where cranes are divided into different groups and only cranes in the same group can interfere with each other. Such crane scheduling problems occur, for example, at indented berths or in container yards where double rail‐mounted gantry cranes stack containers such that cranes of the same size can interfere with each other but small cranes can pass underneath larger ones. We propose a novel algorithm based on Benders decomposition to solve this problem to optimality. In a computational study, it is shown that this algorithm solves small and medium‐sized instances and even many large instances within a few seconds or minutes. Moreover, it improves several best known solutions from the literature with regard to the simpler problem version with only one crane group. We also look into whether investment in more complicated crane configurations with multiple crane groups is actually worthwhile.  相似文献   
7.
为研究高速破片撞击充液容器形成的液压水锤效应,设计一套试验装置和测试方法,试验破片撞击充液容器产生空腔的变化过程、液体中不同位置处的压力变化以及前后面板的变形情况。试验发现:破片撞击容器后面板时会出现一圈空化气泡,气泡在后面板内表面从撞击点位置迅速沿径向扩展;液压水锤初始冲击阶段,距离撞击点较近区域在初始冲击波压力脉冲过后会出现一个较大负压,而距离撞击点较远区域不受负压影响;破片撞击速度对容器前面板最大变形影响较小,变形范围随着撞击速度的增大沿撞击点向四周扩展。后面板的最大变形及变形范围都随着破片撞击速度的增大而变大。  相似文献   
8.
This article treats the problem of subdividing an area for storing containers such that the workload is evenly shared among the cranes operating the resulting subareas. We consider two crane sets: while noncrossing constraints between cranes of the same set need to be observed, cranes of different sets do not interfere. Such a problem setting is, for instance, relevant for scheduling the (un‐)loading of vessels by parallel quay cranes operating on opposing berths or in container yards with cross‐over cranes. We formalize the resulting optimization problem, prove computational complexity, and present exact and heuristic solution procedures. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012  相似文献   
9.
The container relocation problem (CRP) is concerned with emptying a single yard‐bay which contains J containers each following a given pickup order so as to minimize the total number of relocations made during their retrieval process. The CRP can be modeled as a binary integer programming (IP) problem and is known to be NP‐hard. In this work, we focus on an extension of the CRP to the case where containers are both received and retrieved from a single yard‐bay, and call it the dynamic container relocation problem. The arrival (departure) sequences of containers to (from) the yard‐bay is assumed to be known a priori. A binary IP formulation is presented for the problem. Then, we propose three types of heuristic methods: index based heuristics, heuristics using the binary IP formulation, and a beam search heuristic. Computational experiments are performed on an extensive set of randomly generated test instances. Our results show that beam search heuristic is very efficient and performs better than the other heuristic methods.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 101–118, 2014  相似文献   
10.
为确保大型橡胶容器的运输适航性,依据中国民用航空局对运输类飞机的应急着陆过载要求,开展着陆冲击试验系统设计。通过冲击平台仿真设计与校核、波形发生器仿真设计、摆锤系统与导向机构设计,构建了着陆冲击试验系统,有效负载约达20 t,最大冲击载荷达到400 t。选取大型橡胶容器作为典型空运物资进行应急着陆实装试验验证,结果表明:冲击波形均近似为三角波,与仿真曲线波形相似,过载峰值分别为侧向1.54g、航向3.06g、9.02g、16.20g,与目标峰值最大相对误差小于3%,峰值对应时间大于50 ms,试验系统符合设计要求。该试验系统可用于空运平台的研制,对于确保飞行安全、降低研制风险、提高空运适航性具有重要的意义。  相似文献   
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