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961.
《Arms and Armour》2013,10(2):145-180
This paper provides new information on the gold sword awarded to Major George Wilson, 39th Regiment of Foot, in 1800 and on the retailer and silversmith, who were commissioned to provide the token.  相似文献   
962.
可信软件是近年来软件工程领域研究的热点,装备软件可信性的研究有助于提升我国国防武器装备的作战效能。首先分析了进行装备软件可信相关研究的必要性;然后阐述可信软件技术的研究现状,主要包括软件可信度量和评估、可信软件的构造与验证、可信软件的演化与控制等三个方面;最后分析了研究可信装备软件面临的挑战。  相似文献   
963.
《Arms and Armour》2013,10(2):128-171
Abstract

The 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   
964.
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   
965.
Full‐system testing for large‐scale systems is often infeasible or very costly. Thus, when estimating system reliability, it is desirable to use a method that uses subsystem tests, which are often less expensive and more feasible. This article presents a method for bounding full‐system reliabilities based on subsystem tests and, if available, full‐system tests. The method does not require that subsystems be independent. It accounts for dependencies through the use of certain probability inequalities. The inequalities provide the basis for valid reliability calculations while not requiring independent subsystems or full‐system tests. The inequalities allow for test information on pairwise subsystem failure modes to be incorporated, thereby improving the bound on system reliability. We illustrate some of the properties of the estimates via an example application. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
966.
In 1897 and 1898, Winston Churchill participated in what late Victorian Britain termed ‘small wars’, first on India's northwest frontier and then in the vast wasteland of the Sudan. Churchill chronicled his experiences in these conflicts in personal letters, dispatches to newspapers, and in his first two books, The Story of the Malakand Field Force and The River War. These writings provide a snapshot of a particular period in the formative years of the great statesman, demonstrating through Churchill's eloquent analyses many of the contradictions concerning the conduct of small wars that have emerged in the present era.  相似文献   
967.
It has long been held that the Federation of Malaya’s counter-insurgency campaign during the First Malayan Emergency (1948–60) was determined by the use of intelligence. Special Branch — the Federation’s primary intelligence agency — dominates the prevailing paradigm of how the insurgent threat was tackled. Conversely, the role of the Royal Air Force (RAF) within this paradigm is very limited. Most observers simply dismiss the role of photoreconnaissance or airstrikes as being largely inconsequential to the counter-insurgency effort. This is perhaps understandable: the Emergency was after all a ‘policing action’ and the insurgents were largely hidden under Malaya’s jungle canopy and amongst the Chinese community. However, further scrutiny reveals that the RAF made a much more significant contribution to the intelligence element of the counter-insurgency campaign than previously realised. First, the RAF decided to locate their Advanced Headquarters with the Army’s General Headquarters. This led to the creation of the Land/Air Operations Room, through which intelligence, tasking and resources were coordinated. Moreover, the RAF put its intelligence teams into the field to provide a practical link between local units and theatre-level assets. Second, with the support of the Army, the RAF established at the beginning of the Emergency the Joint Air Photographic Intelligence Board (Far East). This coordinated all photographic intelligence requirements throughout the Emergency, which was then delivered via the Joint Air Photographic Centre (Far East). Hence, via Joint Operations Centre and JAPIB (FE), the RAF provided both the practical means for effective joint intelligence operations at theatre level throughout the Emergency.  相似文献   
968.
针对一体化火控系统的特殊性,提出了基于PXI计算机的发控技术,介绍了PXI总线计算机在一体化火控系统中的设计理念及其在一体化火控系统中的功能实现.应用表明,PXI计算机在火控系统测控领域具有广阔的应用前景.  相似文献   
969.
针对BP神经网络对初始值敏感、容易陷入局部寻优且收敛速度较慢,提出用粒子群对神经网络的参数进行优化,同时设计了衰减的指数函数对惯性权重进行动态调整以提高算法性能.并应用该算法对导弹飞控系统的逆误差进行补偿,仿真结果表明,该方法对逆误差进行了有效的补偿,避免了局部寻优并提高了学习效率.  相似文献   
970.
分析了单星观测模式下的天基测控系统的可行性,并针对该观测模式下轨道确定中法矩阵的特点,提出了一种基于压缩估计的定轨方法,该方法对法矩阵进行变换,避免了法矩阵奇异造成的误差传递。证明了当满足一定条件时,该压缩方法的估计精度要高于传统的定轨方法。并结合单星观测的特殊性,提出了误差传递因子,设计了单星观测下的压缩估计定轨算法。最后以单星模式下的天基测控系统作为仿真背景进行了仿真试验。结果表明,该压缩估计可有效提高单星观测模式下的轨道确定精度。  相似文献   
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