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941.
Arms transfers provide exporters an avenue to provide security to other states while gaining economic benefits. Arms transfers provide importers an avenue to gain security without having to rely on alliances. Past research uses aggregate measures of the monetary or security value of major weapon system transfers without accounting for strategic differences in possible use in interstate and civil conflict. This article presents a data set on interstate transfers of major weapon systems between 1950 and 2010 building upon Stockholm Peach Research Institute’s Arms Trade Register with several improvements. First, it disaggregates land weapons and air weapons into categories reflecting their strategic capabilities. Second, model level characteristics (e.g. age, speed, and range) are drawn from Jane’s Defence sources. Additionally, the data set covers a larger range of time and states than previous data sets categorizing arms. To demonstrate the usefulness, this article first presents summary statistics of the data set and then replicates an earlier test to show that the effect of human rights and regime types on United States transfers differs across the categories of arms compared to alternative measures of arms transfers.  相似文献   
942.
廉振宇  赵旭  薛奇  李智毅 《国防科技》2017,38(5):040-045
作为国防和装备建设的关键要素,美国防预算是其国家政策和国防战略调整变化的直接"晴雨表",装备预算是表征美装备建设方向重点和资源投向投量的基本指标。本文对美国2001至2016财年国防预算和装备预算数据进行了归集整理。从国防部预算、装备预算、各军种装备预算等多个层面,以及预算性质、预算阶段、预算类别等多个维度进行分析,描绘了美国防预算的基本情况;总结了美国防预算的特点规律;并结合多源情报信息,对战略分析结论进行了综合研判。  相似文献   
943.
颜志强  王伟 《国防科技》2017,38(1):038-042
针对战地环境中军事装备的安全监管问题,分析了战地装备安全监管应用系统的整体结构与功能层次,给出了基于RFID射频识别技术、无线传感器等物联网技术的硬件平台设计方案,以及基于数据采集、分析、融合、传输和可视化技术研发监管控制软件的实现方案。该系统部署应用后可实现对装备实时、连续、精确的分级监管,能够确保装备管理的安全和高效,提高部队指挥决策能力。  相似文献   
944.
充分利用目标尺寸和形状信息,提出了一种基于星凸随机超曲面模型(random hypersurface model, RHM)的非椭圆扩展目标联合跟踪与分类(joint tracking and classification, JTC)算法。将目标空间扩展状态建模为星凸形状,通过目标类别相关先验信息的矢量化建模,建立起其与目标瞬时扩展状态的关系,并在统一的贝叶斯滤波框架下,实现跟踪与分类的一体化处理;进一步对目标运动学状态和扩展状态单独进行建模,并通过构建扩展状态的似然函数,利用粒子滤波实现目标类别概率算式的递推处理。仿真结果表明:与基于椭圆形状的扩展目标JTC算法相比,所提算法能对尺寸相近、形状不同的目标进行准确分类,同时可改善目标状态的估计效果;与基于星凸RHM的扩展目标跟踪算法相比,所提算法能大幅提高目标状态的估计性能。  相似文献   
945.
为了研究分段履带式水陆两栖车的水动力性能,实现减阻增速,将尾翼板安装到水陆两栖车的方艉部,并开展了水池试验和仿真研究,两者的研究结果具有较好的一致性。通过仿真研究了车体的纵向重心位置、尾翼板的长度和角度对水陆两栖车阻力性能的影响,并分析了阻力成分的变化趋势。研究结果表明:车体纵向重心位置在540~560 mm 时,车体所受水阻力最小;在速度为3~5 m/s时,长度为156 mm,与水平面夹角为10°的尾翼板减阻效果最明显,相比于原裸车体的阻力,减阻率达到34.3%;加装尾翼板可以增加车体的尾部中空区长度,相当于增加了水线长,增大了长宽比。该研究表明:适当调节重心位置和优化尾翼板参数,可以有效实现水陆两栖车的减阻增速。  相似文献   
946.
针对电传动装甲车辆负载功率预测功能缺失导致控制作用滞后的问题,提出一种具有较高负载功率预测精度的实时能量管理策略。在分析整车结构的基础上,采用理论分析和数据拟合方法,建立各动力源数学模型。将差分自回归移动平均模型和自适应马尔可夫链两种预测方法相结合,设计非平稳趋势性负载功率组合预测方法。在非线性模型预测控制框架下,构建多目标优化函数,采用序列二次规划法在有限时域内实时求解最优控制指令,优化多动力源协调控制过程。依托硬件在环仿真平台进行多路面行驶实验,对比有无功率预测的能量管理控制效果。结果表明,改进的实时能量管理策略对未来负载功率具有较好的预见性,能够显著优化多动力源协调控制过程,提升车辆燃油经济性,稳定母线电压和电池荷电状态,对传统模型预测控制下的工程应用场景具有一定借鉴意义。  相似文献   
947.
《防务技术》2022,18(11):2034-2044
As an essential component of ammunition, pyrotechnics can control ignition with high reliability. However, due to limits of fabrication technology, traditional pyrotechnics are bulky. To achieve both functionality and miniaturization, MEMS pyrotechnics integrate initiator, safety-and-arming (S&A) device and lead charge and keep all components within a small size. MEMS S&A devices, as the core component to ensure system safety, are difficult to achieve active and rapid response to control signals with high safety and reliability. In order to overcome the difficulty, we propose the design and characterization of a MEMS pyrotechnic with a double-layer barrier S&A device. The MEMS pyrotechnic is a high-integrated device with an overall size of 13.4 × 8.5 × 5.2 mm3. The initiator is a NiCr bridge foil covered with an Al/CuO energetic film, which can generate flame when ignited by an excitation voltage. To match the flame energy, lead styphnate is chosen in this study as the lead charge. The S&A device contains four semi-circular barriers, which are directly driven by V-shape electro-thermal actuators to gain active control of the pyrotechnics' ignition condition with rapid response. To improve the system's reliability, the four barriers are axisymmetrically placed in two layers, two barriers for each layer, to constitute a double-layer structure with a thickness of 100 μm. The ignition test results show that the S&A device can prevent the initiator from detonating the lead charge in safety condition. In arming condition, the lead charge will be detonated.  相似文献   
948.
《防务技术》2022,18(9):1538-1545
3-nitro-1,2,4-tri-azol-5-one (NTO) is a high energy insensitive explosive. To study the shock initiation process of NTO-based polymer bonded explosive JEOL-1 (32%octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), 32% NTO, 28% Al and 8% binder system), the cylinder test, the gap experiments and numerical simulation were carried out. Firstly, we got the detonation velocity (7746 m/s) and the parameters of Jones-Wilkins-Lee (JWL) equation of state (EOS) for detonation product by cylinder test and numerical simulation. Secondly, the Hugoniot curve of unreacted explosive for JEOL-1 was obtained calculating the data of pressure and time at different Lagrangian positions. Then the JWL EOS of unreacted explosive was obtained by utilizing the Hugoniot curve as the reference curve. Finally, we got the pressure growth history of JEOL-1 under shock wave stimulation and the parameters of the ignition and growth reaction rate equation were obtained by the pressure-time curves measured by the shock-initiation gap experiment and numerical simulation. The determined trinomial ignition and growth model (IG model) parameters can be applied to subsequently simulation analysis and design of insensitive ammunition with NTO-based polymer bonded explosive.  相似文献   
949.
《防务技术》2022,18(10):1842-1851
In this study, the approximate and exact solutions for the stationary-state of the solids model with neglecting reactant consumption for both non-uniform and uniform temperature systems were applied on gas ignition under a constant pressure condition. The criticality conditions for a slab, an infinite cylinder, and a sphere are determined and discussed using dimensionless temperatures under constant ambient and surface temperatures for a non-uniform temperature system. Exact solution for a Semenov model with convection heat loss was also presented. The solution of the Semenov problem for constant volume or density as a solid and constant pressure were compared. The critical parameter δ is calculated and compared with those of Frank-Kamenetskii solution values. The validation of the calculated ignition temperatures with other exact solution and experimental results were offered. The relation between critical parameters form Semenov and F.K. models solution was introduced.  相似文献   
950.
2012年1月5日,美国国防部发表了《保持美国的全球领导地位:21世纪的防务重点计划报告》,在"重返亚太"战略的战略背景下,重点针对美国未来的军事力量结构、全球部署态势、军事战略目标等进行了重新规划。新军事战略调整对整个国际格局和地区性大国产生深远影响。随着美国重返亚太的战略调整,军事上的相互依赖程度体现在美日同盟之间尤为突出。本文仅从军事战略角度,运用《权力与相互依赖》中部分理论对其调整下的美日军事同盟机制进行分析。  相似文献   
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