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71.
应急物流保障与军地物流一体化研究   总被引:2,自引:0,他引:2  
应急物流与军事物流都是在特殊条件下发生的物流活动,研究应急物流与军地物流一体化对于促进军事物流的发展具有重要意义.简述了应急物流的基本问题,分析了实现应急物流保障的基本条件:需要完善的应急法律体系、功能健全的应急指挥机构以及高效可靠的应急物流保障平台,阐明了军地物流一体化与应急物流的区别、军地物流一体化的重要作用,并对军地物流一体化下的应急物流保障模式进行了研究.  相似文献   
72.
本文将复合材料细观力学和复合材料微裂纹损伤理论与直接测试方法结合起来,在一次加载条件下直接测得复合材料结构件的弹性常数和损伤变量随外载的变化规律,从而可避免直接测试方法的多次加载的困难。由碳纤维/环氧复合材料圆筒壳的轴压实验的直接测试所得结果比较合理,表明该方法是合理可靠的,特别是在加载条件下直接测得复合材料结构件的损伤发展规律之后,可将复合材料微裂纹损伤理论直接用于工程结构件的动态损伤监测。  相似文献   
73.
考虑横观各向同性压电材料中螺位错的亚音速运动问题。应用复变函数方法 ,得到了运动螺位错产生的电弹场的解析解。当螺位错的运动速度为零时 ,其解便退化成由Pak给出的静止螺位错产生的电弹场。  相似文献   
74.
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   
75.
以污泥龄(SRT)为10 d和30 d的2组A/O-SBR反应器活性污泥为研究对象,探讨了SRT对污泥絮体中磷酸盐形态及其动态变化的影响。结果表明,污泥絮体中的磷主要分布于胞外聚合物(EPS),EPS磷占污泥絮体磷总质量的69.45%~73.36%。正磷酸盐(PO3-4-P)、低分子量聚磷酸盐(LMW Poly-P)和高分子量聚磷酸盐(HMW Poly-P)是污泥絮体磷的主要形态。高SRT(30 d)污泥絮体EPS磷含量明显大于中SRT(10 d),表现为前者较后者有更高的PO3-4-P和HMW Poly-P含量,对应着高SRT(30 d)污泥絮体较中SRT(10 d)有更高的磷含量,前者约为后者的1.37倍。厌氧/好氧反应过程中,中SRT(10 d)污泥絮体EPS磷的厌氧降低量和好氧升高量分别为高SRT(30 d)的1.35倍和1.46倍,主要归因于前者的PO3-4-P和HMW Poly-P较后者有更大的厌氧降低量,而PO3-4-P,LMW Poly-P和HMW Poly-P较后者有更大的好氧升高量,对应着中SRT(10 d)污泥絮体较高SRT(30 d)有更强的厌氧释磷和好氧吸磷能力。  相似文献   
76.
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   
77.
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   
78.
采用球磨法与热压烧结工艺制备了添加w(n-SiO2)=1.0%的铜基纳米复合材料。通过球盘式摩擦磨损试验机测试了复合材料的摩擦磨损性能,采用排水法和场发射扫描电镜(FSEM)研究了复合材料的致密度、显微组织和磨损形貌。结果表明:球磨可提高复合材料的致密度,改善n-SiO2在铜基体中的分散均匀性;随球磨时间的增加,复合材料的动摩擦因数和磨损量先减小后增加,球磨10 h复合材料具有较低的摩擦因数和磨损量,磨损机理主要为磨料磨损。  相似文献   
79.
The dielectric constant (DC) is one of the key properties for detection of threat materials such as Improvised Explosive Devices (IEDs). In the present paper, the density functional theory (DFT) as well as ab-initio approaches are used to explore effective methods to predict dielectric constants of a series of 12 energetic materials (EMs) for which experimental data needed to experimentally determine the dielectric constant (refractive indices) are available. These include military grades energetic materials, nitro and peroxide compounds, and the widely used nitroglycerin. Ab-initio and DFT calculations are conducted. In order to calculate dielectric constant values of materials, potential DFT functional combined with basis sets are considered for testing. Accuracy of the calculations are compared to experimental data listed in the scientific literature, and time required for calculations are both evaluated and discussed. The best functional/basis set combinations among those tested are CAM-B3LYP and AUG-cc-pVDZm, which provide great results, with accuracy deviations below 5% when calculated results are compared to experimental data.  相似文献   
80.
Hexagonal boron nitride nanosheets(HBNNSs)have huge potential in the field of coating materials owing to their remarkable chemical stability,mechanical strength and thermal conductivity.Thin-layer hBNNSs were obtained by a liquid-phase exfoliation of h-BN powders and incorporated into EVA coatings for improving the safety performance of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX).HBNNSs and ethylene-vinyl acetate copolymer(EVA)were introduced to HMX by a solvent-slurry process.For com-parison,the HMX/EVA and HMX/EVA/graphene(HMX/EVA/G)composites were also prepared by a similar process.The morphology,crystal form,surface element distribution,thermal decomposition property and impact sensitivity of HMX/EVA/hBNNSs composites were contrastively investigated.Results showed that as prepared HMX/EVA/hBNNSs composites were well coated with hBNNSs and EVA,and exhibited better thermal stability and lower impact sensitivity than that of HMX/EVA and HMX/EVA/G composites,suggesting superior performance of desensitization of hBNNSs in explosives.  相似文献   
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