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根据典型舰载单脉冲跟踪雷达的组成及工作原理,介绍一种舰载单脉冲跟踪雷达仿真建模方法。重点描述了仿真原理及仿真模型组成,介绍了雷达信号特性仿真、雷达伺服系统仿真、雷达信号处理系统仿真等关键环节的数学仿真模型。结合仿真软件功能需求,给出了软件结构、软件运行流程等仿真软件设计要点。 相似文献
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Gonzalo F-de-Córdoba 《Defence and Peace Economics》2016,27(4):549-570
This paper develops a Dynamic Stochastic General Equilibrium model where national security is an argument in the agent’s utility function and the government chooses optimally the level of military spending to maximize social welfare. National defense depends on military expenditure and on the strategic environment reflecting a potential hostile external threat. We use aggregate data on consumption, investment, and military spending for the US economy to estimate the parameters of the model. Estimation results suggest that consumption and national defense are complements and that military spending variability is mainly explained by external threat shocks although it also depends on the macroeconomic conditions. We compute impulse response functions of the main macroeconomic variables to several shocks: a total factor productivity shock, a defense technology shock, and a strategic environment shock. Surprisingly, we find that the optimal response to an increase in the external threat (a worsening in the strategic environment) will rise output by reducing consumption and increasing investment. 相似文献
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AbstractThe paper examines the relationship between health and military expenditures using pooled cross-sectional (197 countries) and time series (2000–2013) data. Simultaneous equation models were employed to estimate the relationship between an array of public sector expenditures in order to address potential endogeneity. Our empirical findings strongly support the crowding-out hypothesis whereby increased military expenditures reduce the capacity of government to direct expenditures to health expenditures. These findings were robust to alternative specifications explored in the sensitivity analyses. Compared with upper-middle-income countries, the crowding-out effect became more pronounced among lower-middle-income countries. Consequently, this study shows that increased military expenditures negatively impacts health expenditures, and therefore poses as an important risk factor for population health and individual well-being. Moreover, it is the poorest of nations that are most sensitive to the negative effects of increased military expenditures. 相似文献
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This study investigates the statistical process control application for monitoring queue length data in M/G/1 systems. Specifically, we studied the average run length (ARL) characteristics of two different control charts for detecting changes in system utilization. First, the nL chart monitors the sums of successive queue length samples by subgrouping individual observations with sample size n. Next is the individual chart with a warning zone whose control scheme is specified by two pairs of parameters, (upper control limit, du) and (lower control limit, dl), as proposed by Bhat and Rao (Oper Res 20 (1972) 955–966). We will present approaches to calculate ARL for the two types of control charts using the Markov chain formulation and also investigate the effects of parameters of the control charts to provide useful design guidelines for better performance. Extensive numerical results are included for illustration. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
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曾金帆 《武警工程学院学报》2011,(1):18-21
胡主席关于“建设一支能够有效维护国家安全和社会稳定、保障人民安居乐业的现代化武装警察力量”的战略思想,深刻揭示了建设现代化武警与履行职责使命的内在关系。要建设现代化武警,有效履行职责使命,就需要新型的指挥人才。因此,我们必须高瞻远瞩,站在当今世界军事人才培养的“制高点”,注重实效,切实培养出大批高素质的新型军事指挥人才。 相似文献
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Information technology (IT) infrastructure relies on a globalized supply chain that is vulnerable to numerous risks from adversarial attacks. It is important to protect IT infrastructure from these dynamic, persistent risks by delaying adversarial exploits. In this paper, we propose max‐min interdiction models for critical infrastructure protection that prioritizes cost‐effective security mitigations to maximally delay adversarial attacks. We consider attacks originating from multiple adversaries, each of which aims to find a “critical path” through the attack surface to complete the corresponding attack as soon as possible. Decision‐makers can deploy mitigations to delay attack exploits, however, mitigation effectiveness is sometimes uncertain. We propose a stochastic model variant to address this uncertainty by incorporating random delay times. The proposed models can be reformulated as a nested max‐max problem using dualization. We propose a Lagrangian heuristic approach that decomposes the max‐max problem into a number of smaller subproblems, and updates upper and lower bounds to the original problem via subgradient optimization. We evaluate the perfect information solution value as an alternative method for updating the upper bound. Computational results demonstrate that the Lagrangian heuristic identifies near‐optimal solutions efficiently, which outperforms a general purpose mixed‐integer programming solver on medium and large instances. 相似文献
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Dmitrii Usanov G.A. Guido Legemaate Peter M. van de Ven Rob D. van der Mei 《海军后勤学研究》2019,66(2):105-122
The effectiveness of a fire department is largely determined by its ability to respond to incidents in a timely manner. To do so, fire departments typically have fire stations spread evenly across the region, and dispatch the closest truck(s) whenever a new incident occurs. However, large gaps in coverage may arise in the case of a major incident that requires many nearby fire trucks over a long period of time, substantially increasing response times for emergencies that occur subsequently. We propose a heuristic for relocating idle trucks during a major incident in order to retain good coverage. This is done by solving a mathematical program that takes into account the location of the available fire trucks and the historic spatial distribution of incidents. This heuristic allows the user to balance the coverage and the number of truck movements. Using extensive simulation experiments we test the heuristic for the operations of the Fire Department of Amsterdam‐Amstelland, and compare it against three other benchmark strategies in a simulation fitted using 10 years of historical data. We demonstrate substantial improvement over the current relocation policy, and show that not relocating during major incidents may lead to a significant decrease in performance. 相似文献