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排序方式: 共有249条查询结果,搜索用时 15 毫秒
61.
This paper considers a single server queueing system that alternates stochastically between two states: operational and failed. When operational, the system functions as an M/Ek/1 queue. When the system is failed, no service takes place but customers continue to arrive according to a Poisson process; however, the arrival rate is different from that when the system is operational. The durations of the operating and failed periods are exponential with mean 1/cβ and Erlang with mean 1/cβ, respectively. Generating functions are used to derive the steady-state quantities L and W, both of which, when viewed as functions of c, decrease at a rate inversely proportional to c2. The paper includes an analysis of several special and extreme cases and an application to a production-storage system.  相似文献   
62.
本文根据附面层理论,对高速气流中的液滴,因气流和液滴表面相互作用而产生的气动剥离现象进行了分析,建立了气液两相附面层耦合问题的理论分析模型,得到了发生气动剥离时的最小气流速度的计算公式,为液体燃料在高速气流申雾化机理研究提供参考。  相似文献   
63.
The empirical international conflict literature has given much recent attention to interstate armed force’s impact on human well-being. While empirical research has advanced our understanding of the phenomenon considerably, we argue that one conclusion that many studies have reached is preliminary. Some recent research contends that only full-scale war, and not force short of war, has a discernable impact on human welfare or physical quality of life (PQOL). We develop theory on one type of force short of war, large-scale foreign military intervention (FMI), and its potential effects on PQOL. Using interrupted time series and panel corrected standard error methodologies, we find that from 1960 to 2005 large-scale FMI had a statistically and substantively significant impact on the PQOL of populations in 106 developing countries. The specific effect that this type of armed force has depended in large part on the regime type of the target country.  相似文献   
64.
Abstract

This article surveys China’s current naval forces and considers key dynamics and possible Chinese naval futures to 2020, the projected end of Beijing’s ‘strategic window of opportunity’, the idea that a peaceful external environment for economic development, globalization, and integration of China into the global economy allows China to benefit from diversion of US attention to countering terrorism. It considers broad possibilities through 2030, the general limit of public US government projections, and by which time multiple factors will likely slow China’s growth and compete for leadership focus and resources.  相似文献   
65.
This paper explores the relationship between human capital and international conflict. In theory, human capital may increase the opportunity cost of military service and the economic cost of injury and loss of life in combat; it may decrease the benefits of conflict as human capital cannot be easily appropriated or transferred; it may affect societal norms toward peace and war; and it may alter military productivity through new technology and complementarities between military technology and personnel. Using a panel of politically relevant dyads, I find robust empirical evidence that human capital may significantly decrease the likelihood of militarized conflict between nations. In short, the findings suggest that promoting human capital‐oriented development may help to increase peace in the world.  相似文献   
66.
The main objective of the paper is to decipher the military expenditure–economic growth relationship, taking the level of economic development (income) into consideration. Our findings suggest the following: (i) military expenditure has a significantly negative relationship to economic growth for the 23 countries with initial incomes (threshold variable) less than or equal to $475.93; (ii) when the threat level is heightened, economic growth (23 countries) is expected to decrease. However, military expenditure in the presence of sufficiently large threats increases growth; (iii) for the remaining 69 countries whose initial incomes (real GDP per capita in 1992 price) exceed $475.93, no significant relationship exists whether the threat variable is taken into consideration or not.  相似文献   
67.
In recent years, there have been several changes in the weapon‐system acquisition market which have the potential to negatively impact the financial condition of defense contractors. This study evaluates the financial health of defense firms vis‐a‐vis nondefense firms using a fiscal distress identification model developed by E.I. Altman. We conclude that the financial condition of defense firms has deteriorated but the deterioration is the same as experienced by nondefense firms.  相似文献   
68.
The Obama administration has made a great effort to increase the role of advanced conventional weaponry in US national security thinking and practice, in part to help reinvigorate the global nuclear disarmament agenda by reducing the role played by nuclear weapons in the US defense posture. However, such a strategy is fundamentally flawed because increases in US conventional superiority will exacerbate US relative strength vis-à-vis other powers, and therefore make the prospect of a nuclear weapon-free world seem less attractive to Washington's current and potential nuclear rivals. Consequently, it is highly likely that the impact of efforts to increase US advanced conventional superiority through ballistic missile defense and a conventional “prompt global strike” program will ensure that the Obama administration is adopting a pathway to nuclear abolition on which it is the sole traveler for the foreseeable future.  相似文献   
69.
70.
ABSTRACT

The recent use of chemicals in warfare in Syria and Iraq illustrates that, despite the important work of the 1997 Chemical Weapons Convention (CWC), the world has not yet been totally successful in stopping the use of indiscriminate toxic agents in conflicts, either by states or non-state actors. Michael Crowley's excellent and timely new book, Chemical Control, analyzes the use of “riot control agents” (RCAs) and “incapacitating chemical agents” (ICAs), including launch and dispersal systems, by police, paramilitary, and military forces over the last decades and raises the challenging question about where the red line might be drawn between banned and permitted uses of chemicals. He discusses this problem not only in the context of the CWC, which allows use of RCAs for civilian riot control, but also in the context of international law, human rights, and criminal justice, including the Biological and Toxin Weapons Convention and other disarmament and abolition regimes. He proposes a “holistic, three-stage approach” to addressing this issue “for effective regulation or prohibition of the weapon or weapon-related technology of concern.” As we approach the global abolition of a whole class of weapons of mass destruction in the next decade or even sooner, Chemical Control is helpful in better understanding and solving the dilemma of what's actually banned or permitted under international law, and precluding states undermining the chemical weapons ban.  相似文献   
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