Into the black box? Technology sharing in major arms transfers and beyond

From the recipients’ perspective, arms transfers have, through the use of offsets, technology transfers, and industrial participation, become an opportunity to receive not only advanced weapons, but also technologies not otherwise available. How important are friendly relations for securing a military export order? To what extent do buyers demand advanced military or commercial technology and how are these demands accepted by the supplier? How does this influence smaller producers in relation to major producers? These questions are addressed by studying (a) the Joint Strike Fighter/F-35 by Lockheed Martin, USA, and the JAS-39 Gripen aircraft by Saab, Sweden, (b) the Medium Multi-Role Combat Aircraft competition in India for 126 combat aircraft, and (c) the Indian offset policy. In the final section, some long-term consequences are discussed.     

Are non‐lethal weapons a viable military option to strengthen the hearts and minds approach in Afghanistan?

Commanders of the International Security Assistance Force (ISAF) have repeatedly stressed the hearts and minds approach in Afghanistan, in saying that the human terrain is decisive for a successful outcome of the mission. Avoidance of civilian casualties is considered of strategic importance, and by nature highly dependent on the management of tactical level Escalation of Force (EoF) situations. Non‐lethal weapons (NLWs) are expected to enable tactical commanders to avoid innocent civilian casualties in such situations. This article considers a selected NLW on its potential to accomplish this requirement. It uses a defence technology assessment approach to analyse EoF situations experienced by Dutch ISAF forces in which the NLW is inserted. The analysis demonstrates that a range of contextual factors in the Afghanistan high‐risk environment tend to narrow down the window of opportunity for the NLW to help defuse the risk of unintended civil casualties.     

Involving the elephant: technical isolation and the role of India in a possible solution to the Iranian nuclear crisis

Apart from North Korea, no state's nuclear program in the twenty-first century has raised more concern to international security than Iran's. While Iran insists that its nuclear program is strictly for civilian purpose in line with Article IV of non-proliferation treaty, the USA and its allies insist that Iran has military intentions and called for sanctions. The failure of sanctions to deter Iran from its nuclear agenda had made many scholars and policy-makers call for a preemptive attack on Iranian nuclear facilities. Situated within this debate, this paper positions itself as an antagonist to the preemptive airstrike option and argues that involving India in a possible nuclear “iron curtain” against Iran – a move known as technical isolation – remains the best option to the current nuclear crises.     

基于目标先验知识的二次CFAR检测算法

舰船检测与监视有着广泛的军事和民用意义,而SAR图像是舰船检测的有效手段。针对双参数CFAR算法存在的问题,本文提出了一种基于目标先验知识的二次恒虚警检测(CFAR)算法,能自适应的调整检测窗口的大小,有效提高算法的效率。实验证明,该算法在效率和精度方面都有较大提高。     

航天测控通信系统可靠性分析的Krylov子空间投影算法

基于Markov模型对航天测控通信系统进行可靠性分析的过程中,若系统中测控通信设备数量较多,模型中的状态空间随设备数量呈指数增长,将会导致数值计算困难.提出了一种基于Krylov子空间技术的可靠性分析方法,将大规模问题投影至小规模子空间中,求得问题的近似解.实验结果证明,Krylov子空间方法的计算速度及精度优于Ross方法和前向Euler法(forward Euler method,FEM).     

神经网络和DEA方法的炮兵火力毁伤先验评估模型

提出运用BP神经网络理论和数据包络分析(DEA)方法,对炮兵火力毁伤先验评估问题进行研究。利用以往经验数据建立样本集,通过BP神经网络预测模型,对待评估的炮兵火力毁伤计划进行分析,预测其毁伤效益,再建立带有偏好锥结构的DEA评估模型,分析火力计划的可行性和合理性;最后以某部17组炮兵火力毁伤数据进行实例分析。结果表明,该模型能给出科学、明确、可靠的先验评估结果。     

基于灰色系统理论的目标方位估算及应用

针对潜艇作战过程中依据目标方位变化判断战场态势的军事需求,根据灰色系统理论,以实测目标方位序列为原始数据,建立GM(1,1)模型,深入挖掘其内在规律性,对目标方位序列的变化趋势进行科学分析,并估算未来时刻目标方位,用于战术态势判断、检验目标运动要素解算和战术绘算的准确性,以及干预目标运动要素解算,以期望利用有限的数据,获得最大限度的信息,为潜艇指挥员提供决策支持。     

飞机机翼结构损伤仿真研究

飞机结构的战伤模式及战伤程度预测对于制定战场抢修预案及改进战斗生存力设计具有重要意义。采用计算机模拟仿真技术定量分析了飞机机翼结构遭受射弹攻击后的损伤情况。通过损伤仿真讨论了3类情形,一是机翼结构受到简单的侵彻后的冲击效应;二是高速射弹攻击带有翼盒的机翼,而产生流体动力冲压效应;三是在射弹冲击模型中增加爆炸条件,研究射弹以任意角度冲击不同的位置产生的耦合效应。基于AN SY S/LS-DYNA仿真,给出了机翼结构损伤的结果,结论为战伤飞机战场抢修的快速评估提供了科学依据,也为飞机平时修理提供了参考。     

Technical note: Finite-time regret analysis of Kiefer-Wolfowitz stochastic approximation algorithm and nonparametric multi-product dynamic pricing with unknown demand

We consider the problem of nonparametric multi-product dynamic pricing with unknown demand and show that the problem may be formulated as an online model-free stochastic program, which can be solved by the classical Kiefer-Wolfowitz stochastic approximation (KWSA) algorithm. We prove that the expected cumulative regret of the KWSA algorithm is bounded above by where κ₁, κ₂ are positive constants and T is the number of periods for any T = 1, 2, … . Therefore, the regret of the KWSA algorithm grows in the order of , which achieves the lower bounds known for parametric dynamic pricing problems and shows that the nonparametric problems are not necessarily more difficult to solve than the parametric ones. Numerical experiments further demonstrate the effectiveness and efficiency of our proposed KW pricing policy by comparing with some pricing policies in the literature.     

用于SiC光学材料高效加工的电弧增强等离子体加工方法*

由于SiC光学材料具有高化学稳定性,使其在普通的等离子体加工中难以获得较高的加工效率。在等离子体加工实验中,我们发现提高等离子体的自身射频电压,可增强等离子体与SiC材料之间的电弧放电作用,而借助电弧的增强作用提高SiC材料的加工效率,因此本文提出了电弧增强等离子体加工方法。为研究电弧的形成原理,本文使用自制的探针分别测量了普通电感耦合等离子体和电弧增强等离子体的电压。并分别使用传统方法和电弧增强方法对S-SiC进行直线扫描加工实验,证明了电弧增强等离子加工方法在加工过程中具有更高的加工效率。