可信软件研究

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。     

LEACH—DRT算法中基于神经网络的数据预测算法

为了保证无线传感器网络中数据的完整性,针对基于LEACH路由协议的动态轮时间算法存在的问题,提出一种基于人工神经网络的数据预测算法。该动态轮时间算法中,部分簇因调整后的轮时间不足以完成数据的采集而丢失数据。数据预测算法结合传感器节点数据具有时空相关性的特点,将时空延迟算子引入神经网络模型,并通过建立的神经网络模型对数据进行预测。仿真时采用伯克利英特尔实验室的传感器数据,通过Mafl软件对模型进行测试并分析仿真结果。实验结果表明：该算法对连续多个数据的预测效果理想,预测误差始终保持在较低水平。     

William and John Pickering and the garniture made for the Prince of Brunswick under their supervision at the Royal ‘Almain’ Armoury at Greenwich, 1610 to 1612

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.     

Military Power: A Reply

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.     

Inequality‐based reliability estimates for complex systems

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     

Notes on contributors

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.     

PXI计算机在一体化多模式发控系统中的应用

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.     

遗传神经网络在保障资源需求预测中的应用

针对现代战争条件下装备保障资源需求变化快,保障资源预测困难的问题,首先分析了影响装备保障资源需求的因素,根据实际情况选取了平均维修间隔时间(MTBM)、平均修复时间(MTBR)等8项影响装备保障资源需求的关键指标,然后将基于遗传算法(GA)优化的反向传播(BP)神经网络应用于保障资源需求预测中,构建了基于遗传神经网络的需求预测模型,最后利用1980年～2010年实际保障资源需求数据对模型进行了验证.验证结果表明,基于GA优化的BP神经网络预测模型有较快的收敛速度、较强的适应性和较高的预测精度,适用于装备保障资源需求预测.     

基于云理论的装备技术状态预测

通过分析装备技术状态变化的模糊性和不确定性等特性,提出了基于云理论的装备技术状态预测模型.根据装备技术状态劣化趋势,给出了基于云模型的时间序列状态预测方法,有效地运用了装备状态评估中的主观预测知识.将历史趋势与当前趋势相结合,实现了基于时间序列的状态预测.最后以某装备的发动机为研究对象,对发动机状态的动态评估值进行了预测,验证了该状态预测方法的有效性.     

基于压缩估计的单星观测定轨方法研究

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。