对基于BP神经网络的一类非线性控制器的结构改进

对一类基于ＢＰ神经网络的非线性系统控制器进行了改进,从而提出了一种结构更简单的控制器模型。通过数值仿真模拟证实了它比以前的研究者给出的方案能更快地收敛     

某型舰炮故障诊断知识库的建立

本文运用层次模块化构成模型及故障诊断模型的建造方法,提出了建立某型舰炮故障诊断知识库的方法,对构造诊断知识库的六种规则举例予以了说明.     

通用电子系统故障诊断专家系统的研究

本文采用了一种符合人类维修专家故障诊断思路的方法,即层次模块化故障诊断法,来建造通用电子系统故障诊断专家系统。在系统建造中采用了框架和产生式复合知识表达形式表示系统诊断知识,采用了正反向混合推理、不精确推理及层次模块化诊断推理机制,并予具体实现。     

Bureaucracy Does Its Thing: US Performance and the Institutional Dimension of Strategy in Afghanistan

It is not too soon to draw cautionary lessons from the inconclusive results of US performance during more than 11 years of Operation ‘Enduring Freedom’ in Afghanistan. As in Vietnam, fundamental difficulties persist in adapting enduring institutions to the requirements of strategy. At the heart of the matter is tension between the assumptions that underlie counterinsurgency as practiced in Afghanistan and organization of the US Armed Forces, State Department, and Agency for International Development. Knowledge of basic principles and necessary changes is available to answer the question, could the US have done better?     

Design of accelerated life testing plans under multiple stresses

Accelerated life testing (ALT) using multiple stresses is commonly used in practice to resemble the operating stresses at normal operating conditions and obtain failure observations in a much shorter time. However, to date, there is little research into the theory of planning ALT for reliability estimation with multiple stresses. ALT with multiple stresses can result in a large number of stress‐level combinations which presents a challenge for implementation. In this article, we propose an approach for the design of ALT plans with multiple stresses and formulate multistress test plans based on different objectives and practical constraints. We develop a simulated annealing algorithm to efficiently determine the testing plan parameters. We demonstrate the proposed method with examples based on an actual test conducted using three stress types. The obtained optimal test plans are compared with those based on fractional factorial design. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 468–478, 2013     

Directional change‐point detection for process control with multivariate categorical data

Most modern processes involve multiple quality characteristics that are all measured on attribute levels, and their overall quality is determined by these characteristics simultaneously. The characteristic factors usually correlate with each other, making multivariate categorical control techniques a must. We study Phase I analysis of multivariate categorical processes (MCPs) to identify the presence of change‐points in the reference dataset. A directional change‐point detection method based on log‐linear models is proposed. The method exploits directional shift information and integrates MCPs into the unified framework of multivariate binomial and multivariate multinomial distributions. A diagnostic scheme for identifying the change‐point location and the shift direction is also suggested. Numerical simulations are conducted to demonstrate the detection effectiveness and the diagnostic accuracy.© 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013     

分布式放大前传中继辅助多用户对等通信中的鲁棒波束成形

针对分布式放大前传中继辅助多用户对等通信系统研究了存在非理想信道状态信息(CSI)时的分布式中继网络(DRN)鲁棒波束成形设计问题。采用统计CSI误差模型,考虑了两种鲁棒优化问题:一是从公平性的角度出发在DRN总发送功率约束下实现多个目的节点间的信干噪比(SINR)平衡;另一是从有效性的角度出发在保证各个目的节点服务质量需求(SINR大于预设门限)约束下最小化DRN总发送功率。对问题的分析和建模表明,在多用户情况下,这两个问题都是难以求解的优化问题。通过引入半定松弛(SDR)思想,将上述两种优化问题转化为可利用内点法有效求解的半定规划(SDP)问题。最后通过仿真验证了所提设计的鲁棒性能。     

The revisionist historiography of Britain’s decolonisation conflicts and political science theses of civilian victimisation in counterinsurgency

ABSTRACT

Recent historical research exposed the myth of self-restraint as the distinctive feature of British counterinsurgency during decolonisation. This article shows that the revisionist historiography of British counterinsurgency has important, but unnoticed, implications for political scientists. Specifically, historical scholarship challenges the predictions and causal mechanisms of the main social scientific theses of civilian victimisation in counterinsurgency. Using revisionist historians’ works as a source of data, I test those theses against Britain’s decolonisation conflicts. I find that they do not pass the test convincingly. I conclude that political scientists should be more willing to explore the theoretical implications of new historical evidence on counterinsurgency campaigns.     

Global counterinsurgency and US army expansion: the case for recruiting foreign troops

Given the nature of global counterinsurgency operations, the demands of military expansion, and the need for cultural, linguistic, and regional expertise, the United States Army should evaluate the establishment of US-led foreign troop units for its evolving force structure. This article proposes the creation of an American foreign legion based upon the recruitment of US-led, ethnically homogeneous tribal force units to meet the grist mill of counterinsurgency operations. This structured approach would be more beneficial than the current reliance on a de facto American Foreign Legion, represented by private military contractors (PMCs), many of them comprised of foreigners. These PMCs carry a number of oversight, accountability, and legal risks not found in a fully integrated, and US-officered foreign legion. The British Brigade of Gurkhas, the South-West African Police Counter-Insurgency Unit (Koevoet), and the Kit Carson Scouts serve as relevant historical examples where foreign troops were used to supplement national manpower resources.     

Counterinsurgency force ratio: strategic utility or nominal necessity

As a consequence of intervention in Iraq and Afghanistan, force ratio for counterinsurgency (COIN) has come under increased scrutiny. Reduced to its essence, the issue is simply, ‘How many troops does it take to get the job done?’ This answer has been sought by the US military, academia, and think tanks. There have been numerous responses, culminating in several ‘plug-and-play’ equations for minimum force ratios in COIN operations. Due to the impossibility of determining precisely how many insurgent forces there are, it has become common to base force ratios on the population of the country. In the realm of policy, the question above is posed as, ‘How many of our troops does it take to get the job done?’