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191.
利用金属膜电阻设计并制作了用于陡化前沿Marx发生器调试的大功率低电感负载.其阻值约为90Ω,电感约为55nH,基本不具备分散电容.该负载采用线性渐变的圆锥外型结构,有利于减小信号在负载上的反射,配合电容分压器使用能够很好地完成对前沿约为几ns的快前沿高压脉冲的测量.理论估算了该负载的功率容量,并利用PSpice软件模拟了对其进行脉冲方波加载的情况.该负载用于调试陡化前沿的Marx发生器的实验中,获得了幅值约210kV,脉宽近40ns,前沿为5ns的快前沿高压脉冲.多次实验结果表明该负载性能稳定,适用于陡化前沿Marx发生器的调试工作. 相似文献
192.
Todas information and communication network requires a design that is secure to tampering. Traditional performance measures of reliability and throughput must be supplemented with measures of security. Recognition of an adversary who can inflict damage leads toward a game‐theoretic model. Through such a formulation, guidelines for network designs and improvements are derived. We opt for a design that is most robust to withstand both natural degradation and adversarial attacks. Extensive computational experience with such a model suggests that a Nash‐equilibrium design exists that can withstand the worst possible damage. Most important, the equilibrium is value‐free in that it is stable irrespective of the unit costs associated with reliability vs. capacity improvement and how one wishes to trade between throughput and reliability. This finding helps to pinpoint the most critical components in network design. From a policy standpoint, the model also allows the monetary value of information‐security to be imputed. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009 相似文献
193.
动态差分逻辑是一种典型的电路级差分功耗攻击(DPA)防护技术.这种技术通过使逻辑门保持恒定的翻转率来降低电路功耗与数据信号之间的相关性.介绍了一种新型的、基于查找表(Look-Up-Table,LUT)结构的动态差分逻辑(LBDL),以及基于这种逻辑的集成电路设计方法.该设计方法仅需在传统的半定制设计流程中添加少量的替换操作就可以实现 ,因而比其他完全需要全定制设计的动态差分逻辑具有更好的实用性.而相对同样适用于半定制实现的动态差分逻辑 WDDL(Wave Dynamic Differential Logic),LBDL逻辑解决了逻辑门翻转时刻与数据信号之间的相关性,从而比WDDL逻辑具有更好的功耗恒定性.实验结果表明,该设计方法能够有效实现具有抗DPA攻击性能的电路. 相似文献
194.
智能装备已经走入军队、走向战场,创建智能化作战指挥模式是智能化时代作战指挥的必然发展趋势,智能化作战指挥模式需求分析可为智能作战问题研究提供有效的信息。智能化作战指挥模式的需求分析已经具备了一定的物质、理论和技术基础,同时,也具有了一定的构建思路、实践条件和实验平台。在此基础上,本文从军事需求、功能需求和技术需求以及构建要求四个不同角度进行需求分析,以找准创建需求,为后续工作进一步展开奠定基础。 相似文献
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Michael H. Clemmesen 《Defense & Security Analysis》2019,35(1):96-97
The article outlines the essential role of free play elements in various types of exercises for the development of in-depth and practical military professionalism. It thereafter argues why such use of free play contradicts the military science founded Russian Way of War. 相似文献
198.
Soumyanetra Munshi 《Defence and Peace Economics》2019,30(3):278-308
This paper proposes a simple game-theoretic framework for analyzing the relationship between the government, industry and indigenous community, especially in the context of mounting violence surrounding displacement of indigenous communities by governments for the purposes of commercial use of their habitat. It specifically takes into account the possibility of alleged ‘nexus’ between the government and the industry and explores its implications on the level of allocation and utilities of the players. We find that the bias in allocation that occurs when the government and the industry enter a ‘nexus’ can be rectified when there is resistance from the indigenous groups. Moreover, rebellion is a dominant strategy of the indigenous community, irrespective of whether there is ‘nexus’ or not, and being in ‘nexus’ with the government is a best response for the industry. The unique SPNE occurs when there is ‘nexus’ between the industry and the government and resistance by the indigenous groups, corroborating the widespread allegations of ‘nexus’ and evidence of resistance worldwide. We also explore a few extensions of the basic model and present some narrative evidence in support of the theoretical model. 相似文献
199.
We seek dynamic server assignment policies in finite‐capacity queueing systems with flexible and collaborative servers, which involve an assembly and/or a disassembly operation. The objective is to maximize the steady‐state throughput. We completely characterize the optimal policy for a Markovian system with two servers, two feeder stations, and instantaneous assembly and disassembly operations. This optimal policy allocates one server per station unless one of the stations is blocked, in which case both servers work at the unblocked station. For Markovian systems with three stations and instantaneous assembly and/or disassembly operations, we consider similar policies that move a server away from his/her “primary” station only when that station is blocked or starving. We determine the optimal assignment of each server whose primary station is blocked or starving in systems with three stations and zero buffers, by formulating the problem as a Markov decision process. Using this optimal assignment, we develop heuristic policies for systems with three or more stations and positive buffers, and show by means of a numerical study that these policies provide near‐optimal throughput. Furthermore, our numerical study shows that these policies developed for assembly‐type systems also work well in tandem systems. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
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