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891.
892.
提出了一种可用于加油卷盘升降的四杆式液压起落机构的设计方案。分析了四杆式液压起落机构的工作原理,采用复数向量法建立了运动学和动力学数学模型。利用Matlab软件编制了相应的程序进行实例分析和计算,得到了机构关键点的仿真轨迹和有关构件的角位移、角速度及角加速度曲线。运用理论分析计算和软件仿真,验证了机构设计的合理性和方案的可行性。 相似文献
893.
《Arms and Armour》2013,10(1):33-39
AbstractAn argument is presented that Valentine Green’s mezzotint engraving ‘Queen Elizabeth at the Head of her Army at Tilbury-Fort, A.D. 1588’ (1792) was inspired by the late 18th-century life-sized group of three figures representing the same subject that was formerly on show at the Tower of London. The mezzotint presented in Acta Historica Reginarum Angliae is the only known image of the original pre-1828 setup of the display, showing the figure of the queen in a skirt-like piece of armour that has since been re-identified as King Henry VIII’s tonlet armour. 相似文献
894.
《Arms and Armour》2013,10(2):128-171
AbstractThe princely garniture ‘commanded’ to be made by Prince Henry Frederick for his cousin, Prince Friedrich Ulrich, later Duke of Brunswick, from the Royal ‘Almain’ Armoury at Greenwich, during the stewardship of the Master Armourer, William Pickering, his son, John, and the men of the Greenwich workshop, is described, illustrated and discussed. Accounts are presented of the lives and work of the Pickerings and the evidence is reviewed for the manufacture of this last decorated garniture of the Greenwich School. 相似文献
895.
Stephen Biddle 《战略研究杂志》2013,36(3):453-469
This article argues that the prewar planning process for postwar Iraq was plagued by myriad problems, including a dysfunctional interagency process, overly optimistic assumptions, and a lack of contingency planning for alternative outcomes. These problems were compounded by a lack of civilian capacity during the occupation period, which led to a complicated and often uncoordinated relationship with the military authorities who found themselves taking the lead in many reconstruction activities. Taken together, these mistakes meant that US success on the battlefield was merely a prelude to a postwar insurgency whose outcome remains very much in doubt more than three years later. 相似文献
896.
Amy Z. Zeng 《海军后勤学研究》2013,60(1):31-45
In this article, we consider a generic electronic product that can be remanufactured or recycled at the end of its life cycle to generate new profit. We first describe the product return process and then present a customer segmentation model to capture consumers' different behaviors with respect to product return so that the retailer can work more effectively to increase the return volume. In regard to the collaboration between the retailer and the manufacturer, we explore a revenue‐sharing coordination mechanism for achieving a win‐win outcome. The optimality and sensitivity of the critical parameters in four strategies are obtained and examined both theoretically and numerically, which generate insights on how to manage an efficient consumer‐retailer‐manufacturer reverse supply chain, as well as on the feasibility of simplifying such a three‐stage chain structure. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
897.
898.
As the world becomes increasingly globalized, interruptions to international trade cannot be permitted. Piracy off the coast of Somalia has hampered international trade in the region and poses significant risks to the sailors required to navigate those waters. Over the past three years the global community has attempted, through a number of different naval tactics, to stop these acts of piracy; however, these tactics have proven ineffective. This article looks at historical precedence and military theory to support the concept of using convoys to protect the thousands of cargo vessels traveling round the Horn of Africa every year. This tactic will greatly decrease the number of successful pirate attacks and save countless lives in the process. 相似文献
899.
Luke Falkenburg 《Small Wars & Insurgencies》2013,24(3):375-393
Since Operation Enduring Freedom, Central Asian militants, such as the Islamic Movement of Uzbekistan, have fled to Pakistan from their previous strongholds in Afghanistan. However, many militants have begun returning to Central Asia. Thus questions are raised as to what extent militancy has the potential to thrive with the pending North Atlantic Treaty Organization withdrawal from Afghanistan set for 2014? Is militancy a legitimate security threat to Central Asia? What strategies might militants implement? Thus, this article examines the current state of militancy, analyzes militant trends, introduces Afghanistan and Pakistan into the Central Asian equation, and determines the militants' capability and overall strategy. The article concludes that militant Islam, regardless of its current numbers, remains a viable threat to regional security, Afghanistan will be an essential factor for the future of Central Asian militancy, and the form this re-emergence will take becomes apparent. 相似文献
900.
刘春玲 《中国人民武装警察部队学院学报》2013,(11):37-41
政府职能转变是一项浩大、复杂的系统工程,不仅需要正确的方向,也更需要科学的方法.其中,明确性就是一个必须遵守的原则.审视政府消防管理职能50年的文本变迁,对政府职能转变与明确性原则关系进行了现实考察,进而分析明确性原则与政府职能转变关系进路. 相似文献