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151.
为了有效发挥指挥控制(Command and Control, C2)组织集中式决策和协作式决策的决策优势,对具有决策权限动态变化能力的Holonic-C2组织的决策分配问题进行研究。针对群决策中专家固定权重的主观性太强的缺点,提出基于专家权威性和意见一致性相结合的专家组选择方法,提高了决策分配过程中多属性决策的客观合理性;针对决策分配的动态演化问题,提出基于多阶段决策的决策模式演化机制,在考虑属性前后阶段的变化的基础上,给出相邻阶段决策模式跃迁方法。仿真结果表明,所提方法能够给出相对客观的决策模式的优劣排序以及多阶段的演化路线,从而证明了方法的可行性和有效性。  相似文献   
152.
针对现行国际空间法存在的诸多漏洞和缺陷,国际空间大国积极利用这些漏洞寻求开展外空试验的依据,并规避法律的约束以发展外空武器装备,使得外空存在被武器化的风险,外空军备竞赛日益激烈。因此,研究并利用外空条约、关注空间大国开展外空试验的现实做法,可以为开展外空活动提供借鉴和依据。本文重点研究了美国海基反卫试验和轨道快车试验,从试验背景、目的、对外口径以及对外反应几个方面,综合对比分析了试验的现实做法,剖析了美国应对外空条约的做法,从技术上、政策上和法律上得出了如何应对的方法和途径。研究成果可为我国合理合法地开展外空行动提供借鉴,从而赢得国际社会的认可。  相似文献   
153.
作战试验部队是试验鉴定力量体系的重要支撑,是完成装备作战试验的直接载体。美国在装备试验与鉴定方面走在世界前列,建立了一整套行之有效的管理体制,陆军实行试验与鉴定的一体化管理,具有独立的作战试验鉴定部门,没有编设专业化的作战试验部队,试验任务主要根据装备的特性选取未来典型用户的作战部队在真实对抗环境中完成。作战试验部队主要参加作战评估、初始作战试验与评价以及后续作战试验与评价三个阶段的作战试验,在一体化试验小组的协调下,依托靶场完成试验训练任务。本文主要通过对美国陆军试验部队的研究,分析了美国陆军作战试验与鉴定发展概况,重点研究了作战试验部队管理体系,并从整个试验与鉴定系统归纳总结作战试验部队管理及相关工作的主要做法。  相似文献   
154.
《防务技术》2020,16(2):362-373
An increase in the use of the gun barrel will cause wear of the inner wall, which reduces the muzzle velocity and the spin rate of the projectile. The off-bore flight attitude and trajectory of the projectile also change, affecting the shooting power and the accuracy. Exterior ballistic data of a high-speed spinning projectile are required to study the performance change. Therefore, based on the barrel's accelerated life test, the whole process of projectile shooting is reproduced using numerical simulation technology, and key information on the ballistic performance change at each shooting stage are acquired. Studies have shown that in the later stages of barrel shooting, the accuracy of shooting has not decreased significantly. However, it is found that the angle of attack of the projectile increases as the wear of the barrel increases. The maximum angle of attack reaches 0.106 rad when the number of shots reaches 4300. Meanwhile, elliptical bullet hole has appeared on the target at this shooting stage. Through combining external ballistic theory with simulation results, the primary reason of this phenomenon is found to be a significant decrease in the muzzle spin rate of the projectile. At the end of the barrel life, the projectile muzzle spin rate is 57.5% lower than that of a barrel without wear.  相似文献   
155.
《防务技术》2020,16(2):392-400
The optocoupler is a weak link in the inertial navigation platform of a kind of guided munitions. It is necessary to use accelerated storage test to verify the storage life of long storage products. Especially for small sample products, it is very important to obtain prior information for the design and implementation of accelerated degradation test. In this paper, the optocoupler failure mechanism verification test is designed and the experimental results are analyzed and the prior information is obtained. The results show that optocouplers have two failure modes, one is sudden failure and the other is degradation failure; the maximum temperature stress of optocoupler can't exceed 140 °C; the increase of leakage current of optocoupler is caused by movable ions contaminating the LED chip. The surface leakage current is proportional to the adsorption amount. The increase of leakage current makes p-n junction tunneling effect occur which LEDs the failure of the optocoupler. The lifetime distribution model of the optocoupler is determined by the failure physics. The lifetime of the optocoupler is subject to the lognormal distribution. The degeneracy orbit of the optocoupler leakage current is described by a power law model. The estimated values of the orbital parameters are initially calculated and the parameters of its life distribution function are deduced. The above information lays a good foundation for the optimization design and data processing of the accelerated degradation experiment.  相似文献   
156.
紧凑型Tesla变压器的参数测量   总被引:1,自引:0,他引:1       下载免费PDF全文
对设计加工研制的Tesla变压器,根据Smith建议的测量方法,解决了对紧凑Teala变压器耦合系数进行比较准确地测量的问题,实测耦合系数高达0.9,并对耦合系数稍低于理论设计值的原因进行了探讨,同时分析给出了物理原因.此外,根据Teala变压器电路在初次级初、次级短路和低电压充电情形下的实测电压波形,估算出Tesla变压器电路各参数数值.这些数值与理论计算值吻合,并能满足实际高压充电的要求.  相似文献   
157.
基于非独立测试的诊断策略优化生成   总被引:1,自引:0,他引:1       下载免费PDF全文
诊断策略优化设计是测试性设计中的一项重要内容.实际中的测试彼此间并非独立,即测试费用依赖于测试的先后顺序,针对这一问题,提出将测试划分成不同的测试模式,规定当一个测试序列中存在模式变换时必须考虑附加的转换费用.建立了同时考虑测试费用和模式转换费用启发式评估函数,并基于该启发式评估函数设计了近似最优的搜索算法,应用案例验证了本算法.试验表明该方法有效地解决了非独立测试的诊断策略优化生成问题.  相似文献   
158.
GPS-OEM板静电放电效应实验研究   总被引:1,自引:0,他引:1  
研究了静电放电 (ESD)对GPS -OEM板性能的影响。以ESS - 2 0 0AX静电放电模拟器为静电源 ,采用人体 -金属模型对GPS -OEM板进行了静电放电效应实验。实验表明 ,ESD不会对GPS -OEM板造成硬损伤 ,但可以干扰其输出的秒脉冲 (PPS)信号 ,严重影响其定时和定位性能。  相似文献   
159.
Within a reasonable life‐testing time, how to improve the reliability of highly reliable products is one of the great challenges to today's manufacturers. By using a resolution III experiment together with degradation test, Tseng, Hamada, and Chiao (1995) presented an interesting case study of improving the reliability of fluorescent lamps. However, in conducting such an experiment, they did not address the problem of how to choose the optimal settings of variables, such as sample size, inspection frequency, and termination time for each run, which are influential to the correct identification of significant factors and the experimental cost. Assuming that the product's degradation paths satisfy Wiener processes, this paper proposes a systematic approach to the aforementioned problem. First, an intuitively appealing identification rule is proposed. Next, under the constraints of a minimum probability of correct decision and a maximum probability of incorrect decision of the proposed identification rule, the optimum test plan (including the determinations of inspection frequency, sample size, and termination time for each run) can be obtained by minimizing the total experimental cost. An example is provided to illustrate the proposed method. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 514–526, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10024  相似文献   
160.
A system reliability is often evaluated by individual tests of components that constitute the system. These component test plans have advantages over complete system based tests in terms of time and cost. In this paper, we consider the series system with n components, where the lifetime of the i‐th component follows exponential distribution with parameter λi. Assuming test costs for the components are different, we develop an efficient algorithm to design a two‐stage component test plan that satisfies the usual probability requirements on the system reliability and in addition minimizes the maximum expected cost. For the case of prior information in the form of upper bounds on λi's, we use the genetic algorithm to solve the associated optimization problems which are otherwise difficult to solve using mathematical programming techniques. The two‐stage component test plans are cost effective compared to single‐stage plans developed by Rajgopal and Mazumdar. We demonstrate through several numerical examples that our approach has the potential to reduce the overall testing costs significantly. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 95–116, 2002; DOI 10.1002/nav.1051  相似文献   
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