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311.
采用状态变量计算硅整流发电机的工作特性是最新的研究成果.本文将这一成果开发到硅整流发电机坦克供电系统瞬态特性的研究中.实践证明,能大大节省计算工作量.文中有计算实例和与实车试验结果的对比. 相似文献
312.
Alexandra Homolar 《战略研究杂志》2013,36(2):189-217
This article investigates how key actors within the US defence policy community realigned their interests to forge a new consensus on the redirection of US defence strategy following the ‘peace shock’ they faced with the collapse of bipolarity. This consensus centred on the idea that achieving US security in the ‘age of uncertainty’ demanded overwhelming US military power, which was widely interpreted as necessitating military capabilities to fight multiple major theatre wars simultaneously against regional ‘Third World’ adversaries. This helped to preserve many of the principal pillars of US Cold War defence policy through deflecting calls for more radical organisational changes and deeper cuts to defence budgets. 相似文献
313.
The world is mired in history again, as historical modes of competition return and historical grievances fuel the policies of multiple revisionist actors. If the end of history has ended, then it follows that the time is ripe for an engagement with history’s wisdom. We argue that the making of American statecraft—the deliberate, coordinated use of national power to achieve important objectives—can be significantly enhanced by a better understanding of the past. This essay, which draws on the extensive literature on history and statecraft, U.S. foreign policy, and the author’s own research and experiences, offers a defense of the use of history to improve statecraft, as well as a typology of ten distinct ways in which an understanding of history can improve government policy. 相似文献
314.
The economic value, social status and symbolic meaning of small arms are particular and temporal in nature. This is demonstra ted through a historical account of the dynamics of cultural change and adaptation in Nuer society. Specifically, the article shows how attitudes towards small arms shif ted over time from a positive valuation of guns as prestigious objects, to ambivalence between the need for protection and the experience of increased local lawlessness and violence. More generally, it demonstrates how weapon-rela ted activities can only be fully understood when seen against a specific cultural background. Even if the display, use and circulation of weapons appear to carry cross-cultural references, typically as expressions of power and masculine identity, the meaning is always primarily local. Therefore, strategies to reduce the destructive impact of small arms through demand side programs, based on voluntary participation, can only be carried out successfully if built on an in-depth understanding of a particular cultural context. 相似文献
315.
Nick Lloyd 《Small Wars & Insurgencies》2013,24(2):382-403
This article re-examines one of the most infamous incidents in British imperial history: the Amritsar Massacre of 1919, and analyses it within the context of the British Army's minimum force philosophy. The massacre has long been regarded as the most catastrophic failure of minimum force in the history of the British Army. This article reconsiders the arguments over the shooting at Amritsar and the role of Brigadier-General Reginald Dyer, and questions the accepted view that the massacre was such a failure of minimum force. It argues that the circumstances surrounding the massacre must be understood before judging the incident and given these factors it is possible to see it within a minimum force framework. 相似文献
316.
高原环境对柴油机的工作性能影响较大,探索在高原环境下柴油机功率的恢复,对车辆在高原地区正常运行具有重要的意义.基于GT-POWER建立某型大功率柴油机整机数值仿真模型,并验证该模型的准确性;确定二级顺序增压系统方案,建立二级顺序增压系统数值仿真模型,通过增加电动增压器实现二级顺序增压的方法恢复柴油机高原使用功率. 相似文献
317.
为了满足偏远岛屿小功率用电保障需求,根据波浪能特点,提出一种新型漂浮式微型波力发电装置。利用重锤惯性定心原理,建立浮动"机架",解决漂浮体内部相对固定问题;采用机-电直接转换系统,提高波浪能的利用效率;研究系统的原理与结构,分析系统的功能特点和主要运动参数。研究结果表明,漂浮式微型波力发电装置具有结构原理新颖、传动效率高、传动质量好与轻巧便携等优点。该研究为漂浮式微型波力发电装置的研发与应用奠定了基础。 相似文献
318.
多个电源模块并联供电系统,最广泛使用基于最大电流方法的自动均流技术,通过专用的模拟均流总线,传输与模块最大电流成正比的电压信号,各个模块使用该电压信号实现均流.该模拟电压信号很容易受到各种噪声影响,导致均流控制失败.针对该问题,设计了单线数字均流总线,实现最大电流值的数字传输.分析结果表明,设计的单线数字均流总线能够实现模拟均流总线相同的功能,并且具有更强的抗干扰能力. 相似文献
319.
This article analyzes the North Korean nuclear crisis from a balance-of-power perspective. It is in the long-term interests of international peace for a secure and independent North Korea to serve as a buffer between US and Chinese ground forces. However, the conventional military advantage of the South Korean-American alliance over North Korea has grown drastically since the end of the Cold War, threatening North Korea’s survival. Since North Korea lacks any reliable ally, nuclear weapons represent its most cost-effective way to restore a balance of power and thus secure itself. Accepting security guarantees in exchange for its nuclear arsenal is rhetorically appealing but not a viable approach. North Korea’s development of intercontinental ballistic missiles (ICBMs), however, has overcompensated for the post-Cold War imbalance, inviting talk in Washington of waging a preventive war. Persuading North Korea to give up its ICBM capability, not its nuclear arsenal, should therefore be the primary objective of US diplomacy. 相似文献
320.