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排序方式: 共有411条查询结果,搜索用时 15 毫秒
211.
采购制度改革是“十五”期间解放羊提出的一项重要课题。根据上级有关改革精神和要求,分析防化研究院科研设备物资采购管理现状。并提出改革总体思路和具体措施。 相似文献
212.
The article presents problems related to mechanical protection of vehicles with different add-on armours against chemical,biological and radiological contamination.This applies to vehicles with additional passive,reactive and hybrid protection in the form of cassettes against piercing with anti-tank pro-jectiles,piercing with their kinetic energy of impact,and as a result of chemical energy of shaped charges as well as explosively formed projectiles.It has been shown how increased ballistic protection of these vehicles at the same time reduces their decontaminability in various places of the vehicle due to the increased additional surface of the vehicle with cassettes.Prevention of contamination of these cassettes has been presented as a way of reducing hard to reach surface for decontamination and a method of insulating construction elements(stands),fixing these cassettes to the vehicle,from the environment to prevent contact with contaminated liquids and dusts.The selection of appropriate materials is shown,which may affect the improvement of the decontamination efficiency of the vehicle with such cassettes.This applies to the use of materials with low absorption of chemical warfare agents,which prevent the accumulation of large amounts of these agents on contaminated surfaces and improve the effectiveness of decontamination.It also shows how to ensure better access of the disinfectant to as much of the vehicle surface as possible,covered with cassettes that have been contaminated.It shows how a vehicle,in particular with such cassettes,can provide protection against radar detection when Radar Absorbent Material is used on vehicle cassettes. 相似文献
213.
本文研究了北约军需物资编目的成绩和作用,分析了我国军用物资与装备、国防科技工业物资、国家装备动员资源、军民通用资源和应急物资等物品编码的差异,指出物品代码不统一的状况制约了军地信息对接的效率,阐述了军地统一物品编码的意义。此外,还提出统一物品编码工作具有公共服务特性,属于“新基建”范畴,并规划了按“新基建”实施军地统一物品编码的路线图:组建军地统一物品编码管理机构;制定编码国家标准,按“新基建”程序申报国家项目;开发物品编码系统;实施军地统一物品编码;建设物品代码大数据中心,逐步推广应用,稳步树立军地统一物品代码的权威。 相似文献
214.
Projectiles made of reactive structure materials(RSM)can damage the target with not only kinetic but also chemical energy,but the enhanced damage potential of RSM may become compromised if extreme loading condition disintegrates the projectile before the target is reached.In this work,a ductile coating of Ni was introduced to a tungsten-zirconium(W-Zr)alloy,a typical brittle RSM,to preserve the damage potential of the projectile.Detonation driving tests were carried out with X-ray photography and gun-powder deflagration driving tests were carried out with high-speed photography for the coated and uncoated RSM samples,respectively.The craters on the witness target were analyzed by scanning electron microscopy and X-ray diffraction.The Ni coating was found to effectively preserve the damage potential of the W-Zr alloy under extreme loading conditions,whereas the uncoated sample fractured and ignited before impacting the target in both detonation and deflagration driving.The crack propa-gation between the reactively brittle core and the ductile coating was analyzed based on the crack arrest theory to mechanistically demonstrate how the coating improves the structural integrity and preserves the damage potential of the projectile.Specifically,the Ni coating envelops the W-Zr core until the coated sphere penetrates the target,and the coating is then eroded and worn to release the reactive core for the projectile to damage the target more intensively. 相似文献
215.
复合材料层合结构的非线性传热分析 总被引:4,自引:0,他引:4
杨自春 《海军工程大学学报》2000,(5):9-13
基于一阶热层合理论,考虑材料非线性的影响,建立了复合材料层合结构非线性传热分析的热层合理论及其有限元方程.通过数值算例研究了材料非线性对反对称复合材料层合板瞬态温度场的影响. 相似文献
216.
分析了用缓进给方法实现硬脆材料半塑性化磨削的机理,提出了衡量半塑性化磨削效果的破碎率指标,介绍了实验方法和实验结果,对实验结果进行了分析比较。实验结果表明,在普通磨床上可实现硬脆材料的半塑性化磨削,采用缓进给磨削方法可以显著地提高半塑性化磨削的效果。 相似文献
217.
在分析武器装备系统效能特点的基础上,针对装备定型试验的应用需求,提出一种改进可用性-可信性-能力法,以解决传统方法在系统状态划分上无法准确全面描述武器装备实际可用性的问题。提出增加中间状态的策略,对效能综合计算模式、状态描述与计算方法、状态转移计算方法和能力计算方法做整体改进,在此基础上开发了支撑软件SEEK。并以某型主战坦克系统效能评估为例,验证了该方法的可行性和有效性。 相似文献
218.
219.
GPS在导航战中的作用及其干扰对抗研究 总被引:8,自引:1,他引:7
论述导航战的作用和军用范围,进攻导航战的目标和防御导航战的措施以及GPS系统中C/A码的扩展和加密应用,新码的发展和抗干扰能力。并通过应用实例进一步论述对GPS接收机的干扰原理和干扰效果分析以及美、俄两国发展GPS干扰机的技术现状。 相似文献
220.
针对全军装甲装备技术保障信息系统的开发,划分了系统的层次结构,提出了建立技术保障数据仓库的概念,并结合现有各个技术保障信息管理子系统模型,具体规划了面向决策分析的技术保障数据仓库的模型,研究了其实现方法. 相似文献