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351.
脉冲激光测距机测程指标的自动快速检测   总被引:3,自引:0,他引:3  
分析了目前验收脉冲激光测距机测程指标所采用的方法——“消光法”存在的不足,并在“消光法”的基础上,通过采用计算机技术、准激光技术和延时模拟空间距离的方法,实现了测程指标自动、快速和不解体检测  相似文献   
352.
研究了形如X'(t)∈-Ax(t)+F(t,x(t)),0≤t≤T,X(0)=x0的微分包含解的存在的局部性和整体性的结果,并在某种条件下研究了解的稳定性。  相似文献   
353.
舷外有源诱饵反导方法研究   总被引:1,自引:0,他引:1  
为提高电子战反导水平和导弹突防能力,根据反导电子战装备发展的趋势,介绍了舷外有源诱饵的原理和特点,分析了欺骗干扰、压制干扰和组合干扰3种舷外有源诱饵作战使用的典型模式,从实际试验和仿真2方面研究了舷外有源诱饵对抗反击导弹的效果.研究内容对反导电子战装备的研发和作战使用以及反舰导弹突防研究具有一定参考价值.  相似文献   
354.
The sequential order statistics (SOS) are a good way to model the lifetimes of the components in a system when the failure of a component at time t affects the performance of the working components at this age t. In this article, we study properties of the lifetimes of the coherent systems obtained using SOS. Specifically, we obtain a mixture representation based on the signature of the system. This representation is used to obtain stochastic comparisons. To get these comparisons, we obtain some ordering properties for the SOS, which in this context represent the lifetimes of k‐out‐of‐n systems. In particular, we show that they are not necessarily hazard rate ordered. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
355.
We study a stochastic inventory model of a firm that periodically orders a product from a make‐to‐order manufacturer. Orders can be shipped by a combination of two freight modes that differ in lead‐times and costs, although orders are not allowed to cross. Placing an order as well as each use of each freight mode has a fixed and a quantity proportional cost. The decision of how to allocate units between the two freight modes utilizes information about demand during the completion of manufacturing. We derive the optimal freight mode allocation policy, and show that the optimal policy for placing orders is not an (s,S) policy in general. We provide tight bounds for the optimal policy that can be calculated by solving single period problems. Our analysis enables insights into the structure of the optimal policy specifying the conditions under which it simplifies to an (s,S) policy. We characterize the best (s,S) policy for our model, and through extensive numerical investigation show that its performance is comparable with the optimal policy in most cases. Our numerical study also sheds light on the benefits of the dual freight model over the single freight models. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
356.
边防工作作为国防的重要组成部分,涉外性强,受周边安全形势影响大。当前,我国的边防工作既面·l盏着难得的发展机遇,同时更要直面各种挑战。分析周边安全环境对我国边防的影响,可以使我们更好地认清形势,趋利避害,抓住机遇,充分发挥职能作用,确保边防安全稳定。  相似文献   
357.
灭火作战初战是整个灭火战斗的前期战,它的成功与否直接影响到整个灭火战斗的成败。重点论述了如何把握初战的火情侦查、火场救人、控制火势等三个关键环节,以期对基层广大指战员有所指导。  相似文献   
358.
We consider the infinite horizon serial inventory system with both average cost and discounted cost criteria. The optimal echelon base‐stock levels are obtained in terms of only probability distributions of leadtime demands. This analysis yields a novel approach for developing bounds and heuristics for optimal inventory control polices. In addition to deriving the known bounds in literature, we develop several new upper bounds for both average cost and discounted cost models. Numerical studies show that the bounds and heuristic are very close to optimal.© 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
359.
This paper proposes a kurtosis correction (KC) method for constructing the X? and R control charts for symmetrical long‐tailed (leptokurtic) distributions. The control charts are similar to the Shewhart control charts and are very easy to use. The control limits are derived based on the degree of kurtosis estimated from the actual (subgroup) data. It is assumed that the underlying quality characteristic is symmetrically distributed and no other distributional and/or parameter assumptions are made. The control chart constants are tabulated and the performance of these charts is compared with that of the Shewhart control charts. For the case of the logistic distribution, the exact control limits are derived and are compared with the KC method and the Shewhart method. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
360.
针对传统长基线时差探测系统的缺点,提出了全新的动基站时差测量系统并给出了目标的定位原理。在典型布站、信息存在冗余的前提下,通过子集选优法确定了最佳定位算法,并根据工程应用的需要确定了更加合理简捷的定位算法,统计仿真表明了该算法的有效性。最后,计算了目标高度测量精度并归纳了其特点,给出了有益的结论。  相似文献   
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