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941.
本文为在野战条件下检测雷达测距系统的性能提供一种新型微波目标信号模拟器,闸述其工作原理及功能。除在检测雷达测距系统性能上已得到实际应用外,还论述了可以进一步开发的应用项目,因为不受场地和气候条件的限制,从而获得较好的效能、效率和效益。 相似文献
942.
操作系统是紧靠硬件的基础软件,它既是应用软件安全的坚实基础,又是硬件不安全因素的屏蔽器.在操作系统安全隐患和嵌入式操作系统技术特点的基础上,提出信息保护、空间域保护和时间域保护等增强操作系统安全性的几种方法,以提高嵌入式系统抗击系统本身缺陷或敌方恶意攻击等安全威胁的能力.上述几种安全保护技术已在嵌入式Linux中进行验证,并取得满意的结果. 相似文献
943.
Burn-in is the preconditioning of assemblies and the accelerated power-on tests performed on equipment subject to temperature, vibration, voltage, radiation, load, corrosion, and humidity. Burn-in techniques are widely applied to integrated circuits (IC) to enhance the component and system reliability. However, reliability prediction by burn-in at the component level, such as the one using the military (e.g., MIL-STD-280A, 756B, 217E [23–25]) and the industrial standards (e.g., the JEDEC standards), is usually not consistent with the field observations. Here, we propose system burn-in, which can remove many of the residual defects left from component and subsystem burn-in (Chien and Kuo [6]). A nonparametric model is considered because 1) the system configuration is usually very complicated, 2) the components in the system have different failure mechanisms, and 3) there is no good model for modeling incompatibility among components and subsystems (Chien and Kuo [5]; Kuo [16]). Since the cost of testing a system is high and, thus, only small samples are available, a Bayesian nonparametric approach is proposed to determine the system burn-in time. A case study using the proposed approach on MCM ASIC's shows that our model can be applied in the cases where 1) the tests and the samples are expensive, and 2) the records of previous generation of the products can provide information on the failure rate of the system under investigation. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 655–671, 1997 相似文献
944.
Zhi-Long Chen 《海军后勤学研究》1998,45(3):279-295
We consider the parallel replacement problem in which machine investment costs exhibit economy of scale which is modeled through associating both fixed and variable costs with machine investment costs. Both finite- and infinite-horizon cases are investigated. Under the three assumptions made in the literature on the problem parameters, we show that the finite-horizon problem with time-varying parameters is equivalent to a shortest path problem and hence can be solved very efficiently, and give a very simple and fast algorithm for the infinite-horizon problem with time-invariant parameters. For the general finite-horizon problem without any assumption on the problem parameters, we formulate it as a zero-one integer program and propose an algorithm for solving it exactly based on Benders' decomposition. Computational results show that this solution algorithm is efficient, i.e., it is capable of solving large scale problems within a reasonable cpu time, and robust, i.e., the number of iterations needed to solve a problem does not increase quickly with the problem size. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 279–295, 1998 相似文献
945.
Adam Janiak 《海军后勤学研究》1998,45(1):99-113
The paper deals with a problem of scheduling a set of jobs on a single machine. Before a job is released for processing, it must undergo some preprocessing treatment that consumes resources. It is assumed that the release date of a job is a linear decreasing continuous function of the amount of a locally and globally constrained, continuously divisible resource (e.g., energy, catalyzer, financial outlay, gas). The problem is to find a sequence of jobs and a resource allocation that will minimize the maximum job completion time. Such a problem appears, for example, in the ingot preheating and hot-rolling process in steel mills. It is shown that the problem is strongly NP-hard. Some polynomially solvable cases of the problem and approximate algorithms with both experimental and worst-case analysis are presented. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 99–113, 1998 相似文献
946.
Ronald D. Fricker 《海军后勤学研究》1998,45(1):1-22
This paper revisits the modeling by Bracken [3] of the Ardennes campaign of World War II using the Lanchester equations. It revises and extends that analysis in a number of ways: (1) It more accurately fits the model parameters using linear regression; (2) it considers the data from the entire campaign; and (3) it adds in air sortie data. In contrast to previous results, it concludes by showing that neither the Lanchester linear or Lanchester square laws fit the data. A new form of the Lanchester equations emerges with a physical interpretation. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 1–22, 1998 相似文献
947.
Carlos Solar 《战略研究杂志》2019,42(3-4):507-531
This article explores current developments in Chile, where since the return to democracy in 1990, the elected authorities have reconfigured the nation’s military resources in favour of four action pillars: peacekeeping and international conflict management, landmine removal and gun disarmament, emergency and catastrophe response, and a concern for human, economic and social rights. Successive defence policies offer a valuable case study for exploring the trade-offs between security, traditional and non-traditional threat management and institutional capabilities. The article argues that human security policymaking is not free from undesired outcomes; specifically, regarding how to reconvene the role of the armed forces when conventional war seems a thing of the past. The paper focuses on the interagency policy implications and the challenges ahead for civilians and the military. 相似文献
948.
针对容器技术在网络层面缺乏控制的问题,设计一套面向大规模容器集群的网络控制架构,分别从容器集群网络的灵活组网、智能适配以及安全隔离三个方向进行研究,主要解决大规模容器集群部署中的网络适配和隔离控制等关键问题。实验结果表明,设计的网络控制架构可以根据网络特点有针对性地实现虚拟局域网的快速划分、网络节点的稳定迁移和节点通信的精确隔离控制。 相似文献
949.
针对无人机在单站测角测距的目标定位过程中受无人机姿态角误差影响较大的问题,提出一种对辅助信标进行探测并与惯性传感器相结合的无人机姿态求解方法。建立基于容积卡尔曼滤波的惯性传感器姿态求解模型,采用梯度下降法对基于辅助信标的无人机位姿参数进行求解,并综合它们的结果对无人机的姿态偏差进行估计和校正,最后完成了不同视场条件下的目标定位和仿真计算。结果表明,所提方法对无人机目标定位精度有明显提高。 相似文献
950.
Stephen Deakin 《Journal of Military Ethics》2018,17(1):54-71
Military units can become to some extent self-governing in war-time battle. At times, they may take the discipline of their soldiers into their own hands and such discipline may be severe. This paper examines incidents in the British military, in both World Wars, where British soldiers were killed by their comrades because they would not fight in the heat of battle. The judicial execution by the military authorities of deserters in the First World War led to much controversy in Britain. It may be much less well-known that in both World Wars there was, on occasion, an extra-judicial practice within the British military of executing soldiers who would not fight in the heat of battle. In such situations ethical dilemmas become very difficult indeed and some of the relevant issues are examined here. 相似文献