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针对工程项目目标控制问题,通过德尔菲法确定工程项目目标控制的主要影响因素,基于系统动力学反馈与仿真分析理论建立了工程项目目标控制系统动力学模型。采用专家打分法确定参数,利用Vensim软件对模型进行模拟演化和算例分析,讨论不同策略和策略组合的工程项目目标控制效果,最终得到基于算例工程的理想方案为0时增加人工8人,0时加班1 d,管理费水平为3。采用该方案,该工程的完工时间提前47.2%,质量下降2.0%,费用上升6.7%。通过不同策略和策略组合的效果比较,得出结论:加班宜尽量少用,尤其要避免连续加班;尽量避免无效管理费用支出,但对于可以带来管理水平提高的管理费用支出宜适量增加;增加人工越早越好。 相似文献
413.
Mahdi Tavangar 《海军后勤学研究》2014,61(7):549-556
Most of the research, on the study of the reliability properties of technical systems, assume that the components of the system operate independently. However, in real life situation, it is more reasonable to assume that there is dependency among the components of the system. In this article, we give sufficient conditions based on the signature and the joint distribution of component lifetimes to obtain stochastic ordering results for coherent and mixed systems with exchangeable components. Some stochastic orders on dynamic (or conditional) signature of coherent systems are also provided. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 549–556, 2014 相似文献
414.
Within a panel VAR framework and utilizing generalized impulse response and forecast error variance decomposition analysis, we explore the dynamic effects of terrorism and crime on public order and safety spending across European countries during the period 1994–2006. Our findings show that a ‘shock’ in terrorism and/or in crime, significantly increases the subsequent trajectory of public order and safety spending. As a by-product, we find that public spending is ineffective in reducing observed crime or terrorism. 相似文献
415.
Richard B. White 《The Nonproliferation Review》2014,21(3-4):261-274
The Indian government has not made a public comment about the status of its nuclear weapon program since approving a nuclear doctrine in 2003. However, there is now enough information in the public domain to determine that the command-and-control system for the nuclear program has steadily matured in accordance with the intent of the approved nuclear doctrine. The Indian government has successfully mitigated many of the issues that plague the conventional military. The result is a basic command-and-control system that is focused only on the delivery, if ordered by the prime minister, of nuclear weapons. The system is not as robust as those of the United States and Russia, but is in place and ready as new Indian nuclear weapons enter into operation. The command-and-control system is developing to meet India's needs and political compulsions, but not necessarily as part of a more assertive nuclear policy. 相似文献
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我国现存最早的兵书《孙子兵法》,蕴含着许多克敌制胜的谋略,其中“奇正”思想在孙武战术思想体系中占有重要的位置。研究孙子“奇正”思想,并借鉴运用于武警部队反恐怖行动,对有效处置恐怖事件有着重要的现实意义。 相似文献
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《防务技术》2014,10(2):211-218
It has been said that, once a bomb casing has fractured, “detonation gases will then stream around the fragments or bypass them, and the acceleration process stops there.” However, while apparently copious gas flow through casing fractures indicates some pressure release, it is also an indication of significant gas drive pressure, post casing fracture. This paper shows two approaches to the problem of calculating the actual loss of drive. One presents first-order analytical calculations, in cylindrical geometry, of pressure loss to the inside surface of a fractured casing. The second shows the modelling of a selected example in the CTH code. Both approaches reveal that gas escape, while occurring at its own sound-speed relative to the adjacent casing fragments, has to compete with rapid radial expansion of the casing. Together with some historic experiments now publicly available, our calculations indicate that post-fracture casing fragment acceleration is, for most systems, unlikely to be reduced significantly. 相似文献
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