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61.
文中论述了运用微型计算机(IBM-PC)进行复合材料强度准则研究的方法,包括强度包络线绘制、双向加载数据采集及实验数据处理等,同时还研究了如何确定双向试验中的破坏载荷值,并在分析实例中提供了较详细的数据。  相似文献   
62.
航空装备是空军武器装备的主体,做好航材保障工作对于充分发挥装备作战效能,确保装备的作战使用具有重要意义。描述了应急需求冲击条件下缓冲控制问题,建立了应急航材配送网络影响缓存因素模型,进而建立了完整的应急航材需求冲击的缓冲策略设计框架,并进行了应急航材缓存分配建模。分别采用BP-GA方法对应急航材需求进行测算;保噪正态分布进行了缓冲策略公式的推演,需求冲能模型进行了单个缓存分配,并结合算例说明了其有效性。  相似文献   
63.
本文介绍了满足微带天线使用温度要求的聚合物基复合材料设计的方法与过程。按照这种方法,设计并制造了一批微带天线产品,经高低温测试,证明都符合设计要求。  相似文献   
64.
首先分析了研发与制造一体化技术是适应武器装备柔性化制造需求的先进制造技术,然后介绍了装备研发与制造一体化技术的涵义和体系结构,分为以研发为中心的研发与制造一体化技术和以制造为中心的研发与制造一体化技术。最后详细研究了其中的物资供应支持系统及其体系结构。  相似文献   
65.
ABSTRACT

Researchers have recently proposed a new approach to nuclear-arms-control verification, dubbed “deferred verification.” The concept forgoes inspections at sensitive nuclear sites and of nuclear weapons or components in classified form. To implement this concept, a state first divides its nuclear program into a closed segment and an open segment. The total fissile-material inventory in the closed segment, which includes the weapon complex, is known and declared with very high accuracy. Essentially no inspections take place in the closed segment. In contrast, inspectors have access to the open segment, which includes in particular the civilian nuclear sector. The fissile-material inventory in the open segment is known with less accuracy, but uncertainties can be reduced over time using nuclear-archaeology methods. Deferred verification relies primarily on established safeguards techniques and avoids many unresolved verification challenges, such as the need for information barriers for warhead confirmation measurements. At the same time, deferred verification faces some unique challenges. Here, we explore some of these challenges and offer possible solutions; to do so, we examine possible noncompliance strategies in which a state would seek to withhold a higher-than-declared inventory.  相似文献   
66.
应急物资调度问题是个典型的需求可拆分的车辆路径问题,区别于传统的车辆路径问题,将每个需求节点只能由一辆车访问的约束去除,允许需求节点由多辆车进行访问。针对应急物资调度问题的特点,建立相应的多目标车辆路径数学规划模型(SDVRP),并根据模型特点设计改进蚁群优化算法。最后,进行相应的算例分析,验证了该模型和算法的有效性。  相似文献   
67.
《防务技术》2022,18(12):2141-2149
Explosive reactive armor (ERA) is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge jets. Considering mobility, the aim is to design a protection system with a minimal amount of required mass. The efficiency of an ERA is sensitive to the impact position and the timing of the detonation. Therefore, different designs have to be tested for several impact scenarios to identify the best design. Since analytical models are not predicting the behavior of the ERA accurately enough and experiments, as well as numerical simulations, are too time-consuming, a data-driven model to estimate the displacements and deformation of plates of an ERA system is proposed here. The ground truth for the artificial neural network (ANN) is numerical simulation results that are validated with experiments. The ANN approximates the plate positions for different materials, plate sizes, and detonation point positions with sufficient accuracy in real-time. In a future investigation, the results from the model can be used to estimate the interaction of the ERA with a given threat. Then, a measure for the effectiveness of an ERA can be calculated. Finally, an optimal ERA can be designed and analyzed for any possible impact scenario in negligible time.  相似文献   
68.
《防务技术》2022,18(9):1578-1588
In this paper, the reaction characteristic and its application in shaped charge warhead of a novel reactive material, which introduced copper (Cu) and plumbum (Pb) into traditional polytetrafluoroethylene/aluminum (PTFE/Al), are studied. The thermal analysis and chemical reaction behavior of the PTFE/Al/Cu/Pb mixture are investigated by Differential Scanning Calorimetry (DSC),Thermo-gravimetry (TG), and X-ray Diffraction (XRD) techniques. Then, the shaped charge liners with PTFE/Al/Cu/Pb reactive materials are fabricated, and the X-ray experiments show that they could form reactive jets with excellent performance under the detonation effects of the shaped charge. Based on that, the penetration experiments of shaped charge with PTFE/Al/Cu/Pb reactive liner against steel plates are carried out, and the results demonstrate that the PTFE/Al/Cu/Pb reactive jets could produce a deeper penetration depth compared to the traditional PTFE/Al reactive jets. Meanwhile, the PTFE/Al/Cu/Pb reactive jets also show significant inner-blast effects, leading to dramatically cracking or fragmentation behavior of the penetrated steel plates. This new PTFE/Al/Cu/Pb reactive liner shaped charge presents enhanced penetration behavior for steel targets that incorporates the penetration capability of a high-density and ductility jet, and the chemical energy release of PTFE-matrix reactive materials.  相似文献   
69.
公民教育目前已经成为我国理论与实践关注的重要领域。《新疆》作为新疆维吾尔自治区义务教育阶段的地方教材,在了解新疆历史、地理和各民族发展等区情方面发挥了积极的作用。地方教材是否具备公民教育理念和内容,以及在多大程度上体现了公民教育的核心内涵。文章采用内容分析的方法对新疆地方教材进行研究,揭示教材的积极方面和存在问题,为地方教材的进一步完善提供参考,进而促进新疆少数民族地区基础教育的发展。  相似文献   
70.
The 2014 Nuclear Security Summit (NSS) in The Hague was a resounding success, both in organizational terms and in terms of substance. The new substance can be found in the Communiqué, as well as in innovative joint statements by participants, all of which may be considered as implementation of actions decided upon in the Final Document of the 2010 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons. The next two years in the NSS process cannot be business as usual. This viewpoint makes some suggestions for NSS states to undertake between now and the final summit in 2016, including preparations for winding down the NSS process as we know it.  相似文献   
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