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排序方式: 共有431条查询结果,搜索用时 8 毫秒
421.
针对步进电机存在负载摄动和失步超步问题,提出了一种基于粒子群优化算法的混合灵敏度设计方法。在H∞混合灵敏度约束下,采用粒子群算法寻找能够反映系统特性的适应度函数最优值,在搜索到合适的加权阵基础上,利用Matlab得到了H∞最优控制器,并利用优化控制器对步进电机进行控制仿真实验。实验结果表明:该系统具有响应快速平稳、抗负载扰动强等特点。 相似文献
422.
为了数值研究宽广温度范围内Mg/H2O的反应特性,分别建立了考虑部分MgO在液滴表面凝聚的Mg/H2O扩散燃烧模型和基于Arrhenius公式的Mg/H2O反应动力学模型.数值研究了Mg/H2O反应速率在扩散控制和化学动力学控制下随反应条件变化的规律.研究结果表明,Mg液滴扩散燃烧时间计算结果与文献值相符;提高温度和水... 相似文献
423.
海上机动目标打击效果评估决策支持系统设计 总被引:3,自引:0,他引:3
针对海上机动目标打击效果评估的特点,运用遥感技术、人工智能技术和模糊评判的方法探索打击效果评估问题。提出一种基于高分辨率遥感图像的打击效果评估决策支持系统,融合人定性分析和机器定量分析的优点,核心是问题处理系统综合运用处理后的遥感信息和支持系统的模型、知识以及数据来评估打击效果,评估模型为二级综合评判模型。对尚处于理论研究阶段的海上机动目标打击效果评估问题有积极的参考意义。 相似文献
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426.
周石峰 《兵团教育学院学报》2007,17(4):14-17
桑巴特的资本主义起源假说在其《奢侈与资本主义》中得到充分展开。桑巴特认为,正是欧洲的奢侈之风生发出现代资本主义,而奢风蔓延又得益于非法爱情的盛行。相反,韦伯则认为现代资本主义源生于新教伦理中的禁欲主义。看似截然二分的两道命题,实则遵循同一思想路径。源自欧洲局部经验的理论抽象,虽不能释疑世界它处为何没有生发出资本主义的世纪性难题,但是对发展之道却不无借鉴意义。 相似文献
427.
Dmitry Adamsky 《战略研究杂志》2020,43(5):611-644
ABSTRACT Andrew W. Marshall, who shaped the way in which contemporary international security experts think about strategy, has been mostly associated with the invention of net assessment. The intellectual sources of this analytical technique, and of the related competitive strategies concept, could be traced to Marshall’s efforts to uncover Soviet post-World War II defense transformations. This article outlines the essence of these Soviet innovations – the empirical frame of reference that inspired Marshall. It provides a new perspective on the history of the net-assessment methodology, advances the debate within strategic studies over the nature of military innovations, and offers insights for experts examining defense transformations worldwide. 相似文献
428.
Craig A. Deare 《Small Wars & Insurgencies》2019,30(1):14-30
ABSTRACTMexico’s defeat in the war that (in the U.S.) takes the country’s name resulted as much from the strategic context created by unrealized nation-building that followed independence as it did from American tactical supremacy. Three centuries of Spanish empire did not translate into national military excellence due to the decades of revolutionary upheaval that followed the sudden decapitation occasioned by Napoleon’s ouster of the monarchy in Madrid. That the occupation which followed major combat provided salutary lessons learned in dealing with guerrillas rather than a Vietnam-like litany of quagmire eventuated from the conscious designs of military leadership steeped in the same Napoleonic dynamic that had produced our opponent. The United States wisely chose to leave issues of state-building and governance to the Mexicans themselves, while annexing the sparsely populated northern remnant of Spanish empire. 相似文献
429.
ABSTRACTThis article analyses findings from an original survey of 187 private military contractors on their incentives for working in the industry. Perceptions of contractors as “greedy, ruthless, and unscrupulous mercenaries” shape both public and military opinions of outsourcing and may impact U.S. military effectiveness, civil–military relations, and contractor identity. We find that contractors are motivated by a range of factors and that their financial experiences are not clearly more positive than that of state military troops. We recommend broad education of military and defense officials and the public in the U.S. and other relevant nations, regarding the true incentives of modern-day, Western contractors, in an effort to dispel misperceptions, increase effective utilisation of contractors, and beneficially shape PMC-military coordination. DoD may consider integrating such training into its current efforts to improve outsourcing, including its Joint OCS Planning and Execution Course, pre-deployment fora, and curricula of advanced military studies schools. 相似文献
430.
James J. Wirtz 《Defense & Security Analysis》2020,36(1):88-100
ABSTRACTA call for innovation as a means to outpace the acceleration of technological change and to bolster capabilities quickly is a central theme of contemporary U.S. Naval Strategy. The need for innovation is accepted, but the integration of readily available technologies into the Fleet is slow. Innovation unfolds according to “Navy-Time,” a cycle lasting between a long-decade and thirty-years. To accelerate the innovation process in the U.S. Navy, the article offers a Concept of Operations for Innovation that outlines how a deliberate process of analysis, weaponisation and integration can move new ideas and weapons into the Fleet in a strategically relevant time-frame. 相似文献