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371.
372.
徐宽宥 《中国人民武装警察部队学院学报》2006,22(6):67-70
加强公安边防群众工作对维护沿边沿海地区社会稳定,推进新时期公安边防工作具有重要意义。从主、客观两方面分析了当前公安边防群众工作中存在的问题,提出公安边防群众工作要坚持为现实斗争服务、为打造服务型机关服务的原则,消除四个误区,提高专业化、信息化和社会化水平,加强保障机制、考核评估机制、奖惩激励机制和监督制约机制建设,推动公安边防群众工作深入开展。 相似文献
373.
弹药塑料包装透湿机理与应用研究 总被引:2,自引:0,他引:2
对弹药塑料包装材料的透湿机理、测试方法、透湿原因、影响因素等进行了分析,并针对塑料包装材料在弹药中的应用现状,提出了提高弹药塑料包装防潮性能的建议。 相似文献
374.
通过到八所军队院校的科研工作调研,总结了他们科研管理的成功经验,简要分析了我院科研工作存在的问题,对进一步加强学院科研工作进行了理性思考,提出了科研工作机制创新的设想。 相似文献
375.
基于仿真互操作标准组织(Simulation Interoperability Standards Organization,SISO)C4ISR/M&S互操作技术参考模型和高层体系结构(High Level Architecture,HLA),C4ISR/M&S互操作HLA仿真设施为架构仿真系统运行体系提出了面向方面框架(Aspect Oriented Framework,AOF)和应用服务平台的技术.AOF能控制C4ISR/M&S互操作所引起的仿真系统结构复杂化,应用服务平台则能丰富仿真系统的运行环境,仿真设施可作为仿真系统通用运行体系的基础组件,支持复杂互操作系统开发. 相似文献
376.
377.
大口径顶置火炮输弹机动力学研究 总被引:1,自引:0,他引:1
为解决大口径顶置火炮弹药自动装填系统的关键技术问题,提出了大口径顶置火炮输弹机各工作阶段的力学模型和动力学方程,并通过输弹速度与时间的计算分析,得到了3种输弹方式的输弹速度与时间关系曲线,其结果对大口径顶置火炮供输弹系统的研究具有较大参考价值。 相似文献
378.
The paper presents the possibilities of, and methods for, acquiring, analysing and processing optical signals in order to recognise, identify and counteract threats on the contemporary battleground. The main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated, including the acquisition of optical emitter signatures, as well as ultraviolet (UV) and thermal (IR) signatures. The physical parameters and values describing the emission of laser radiation are discussed, including their importance in terms of creating optical signatures. Moreover, it has been shown that in the transformation of optical signals into signatures, only their spectral and temporal parameters can be applied. This was confirmed in experimental part of the paper, which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser rangefinders. It has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in “solar-blind” band, various events can be identified quickly and faultlessly. The same is true for IR signatures, where the amplitudes of the recorded signal for several wavelengths are compared. This was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground, namely Rocket Propelled Grenade (RPG) launches and explosions after hitting targets, trinitrotoluene (TNT) explosions, firing armour-piercing, fin-stabilised, discarding sabots (APFSDS) or high explosive (HE) projectiles. The final section describes a proposed model database of emitters, created as a result of analysing and transforming the recorded signals into optical signatures. 相似文献
379.
He-yang Xu Wei-bing Li Wen-bin Li Qing Zhang Ya-jun Wang Xiao-wen Hong Ying Yang 《防务技术》2021,17(5):1650-1659
The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated. A self-designed detonation wave regulator was used to control the detonation and cut the shell. It was found that the self-designed regulator controlled the fragment shape. The macrostructure and micro-characteristics of fragments revealed that shear fracture was a prior mechanism, the shell fractured not only at the position of detonation collision, but the crack also penetrated the shell at the first contact position of the Chapmen-Jouguet (C-J) wave. The effects of groove number and outer layer thickness on the fracture behavior were tested by simulations. When the thickness of the outer layer was 5–18 mm, it has little effect on fragmentation of the shell, and shells all fractured at similar positions. The increase of the groove number reduced the fracture possibility of the first contact position of the C-J wave. When the groove number reached 7 with a 10 mm outer layer (1/4 model), the fracture only occurred at the position of detonation collision and the fragment width rebounded. 相似文献
380.
Yi-jiang Xue Qing-ming Zhang Dan-yang Liu Ren-rong Long Yang-yu Lu Tian-fei Ren Liang-fei Gong 《防务技术》2021,17(2):375-381,383
Impact flash occurs when objects collide at supersonic speeds and can be used for real-time damage assessment when weapons rely on kinetic energy to destroy targets.However,the mechanism of impact flash remains unclear.A series of impact flash experiments of flat-head long-rod projectiles impacting thin target plates were performed with a two-stage light gas gun.The impact flash spectra for 6061 aluminum at 1.3-3.2 km/s collision speeds were recorded with a high-speed camera,a photoelectric sensor,and a time-resolved spectrometer.The intensity of the impact flash exhibited a pulse charac-teristic with time.The intensity(I)increased with impact velocity(V0)according to I∝Vn0,where n = 4.41 for V0 > 2 km/s.However,for V0 < 2 km/s,n = 2.21,and the intense flash duration is an order of magnitude less than that of higher V0.When V0 > 2 km/s,a continuous spectrum(thermal radiation background)was observed and increased in intensity with V0.However,for V0 < 2 km/s,only atomic line spectra were detected.There was no aluminum spectral lines for V0 < 2 km/s,which indicated that it had not been vaporized.The initial intense flash was emission from excited and ionized ambient gases near the impact surface,and had little relationship with shock temperature rise,indicating a new mechanism of impact flash. 相似文献