Insurgent courts in civil wars: the three pathways of (trans)formation in today’s Syria (2012–2017)

As part of research on the meso-foundations of conflict, the field of ‘rebel governance’ examines political institutions that regulate the affairs of civilians in wartime as well as their relations with armed actors. Judicial institutions play an important role in this and research has shown that they are widespread among both historical and current insurgencies. However, usually these bodies have been analysed in the context of one hegemonic faction like the Tamil Tigers in Sri Lanka and the Afghan Taliban. What is missing so far is an analysis of different pathways of (trans)formation of rebel courts. As exemplified by the three case studies of judicial institutions in Eastern Ghouta, Idlib and Aleppo, these are shaped by the distribution of power between ‘same-side’ groups, yielding unipolar, bipolar, or multipolar constellations. The analysis is located on the meso or movement level of insurgent social structures, complementing research on the micro and macro levels.     

A nonparametric Bayes approach to decide system burn-in time

Burn-in is the preconditioning of assemblies and the accelerated power-on tests performed on equipment subject to temperature, vibration, voltage, radiation, load, corrosion, and humidity. Burn-in techniques are widely applied to integrated circuits (IC) to enhance the component and system reliability. However, reliability prediction by burn-in at the component level, such as the one using the military (e.g., MIL-STD-280A, 756B, 217E [23–25]) and the industrial standards (e.g., the JEDEC standards), is usually not consistent with the field observations. Here, we propose system burn-in, which can remove many of the residual defects left from component and subsystem burn-in (Chien and Kuo [6]). A nonparametric model is considered because 1) the system configuration is usually very complicated, 2) the components in the system have different failure mechanisms, and 3) there is no good model for modeling incompatibility among components and subsystems (Chien and Kuo [5]; Kuo [16]). Since the cost of testing a system is high and, thus, only small samples are available, a Bayesian nonparametric approach is proposed to determine the system burn-in time. A case study using the proposed approach on MCM ASIC's shows that our model can be applied in the cases where 1) the tests and the samples are expensive, and 2) the records of previous generation of the products can provide information on the failure rate of the system under investigation. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 655–671, 1997     

Algorithms for computing waiting time distributions under different queue disciplines for the D-BMAP/PH/1

A queueing system characterized by the discrete batch Markovian arrival process (D-BMAP) and a probability of phase type distribution for the service time is one that arises frequently in the area of telecommunications. Under this arrival process and service time distribution we derive the waiting time distribution for three queue disciplines: first in first out (FIFO), last in first out (LIFO), and service in random order (SIRO). We also outline efficient algorithmic procedures for computing the waiting time distributions under each discipline. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 559–576, 1997     

飞航导弹故障飞行落点概率计算方法

针对飞航导弹故障飞行落点概率难以准确计算的问题,通过分析导弹的各个分系统的故障机理重新提出五种故障模式,依据逐系统串联的原理建立了故障模式的概率分配计算模型;在对发射、飞行和故障后坠落等阶段进行分析的基础上建立各故障模式的仿真模型;最后应用蒙特卡洛方法对某型导弹故障飞行落点的概率分布进行了仿真计算。     

一种基于小研抛盘修形的CCOS边缘效应修正方法

计算机控制光学表面技术（CCOS）是加工离轴非球面的一项重要技术。小磨头抛光的边缘效应严重制约CCOS技术的加工精度和加工效率,目前并无十分具体的解决措施。本文在获得影响边缘效应的关键参数后,结合残余误差等高线的路径规划,对CCOS产生的边缘效应产生的翘边现象进行修正,通过对一块体育场形离轴非球面的加工,获得了全口径光学测量数据,为后续精加工提供面形基础。     

小子样下火炮连发密集度的分析与评估

针对火炮连发模式下射弹散布不完全服从正态分布,而缺乏有效密集度估计方法的问题,提出了基于二维云模型和蒙特卡罗方法相结合的火炮连发密集度估计新方法。首先应用蒙特卡罗抽样解决火炮射击样本量少的问题,然后应用二维逆向云算法对火炮射击结果进行密集度估计,最后用二维正向云发生器模拟生成新的射弹散布数据,进而直观地看出弹点分布情况。实例分析表明,该方法更符合火炮连发射弹散布真实情形,分析结果更准确可靠,从而为基地火炮连发密集度试验数据分析与评估提供了一种有效的方法。     

装备使用阶段后续备件采购模型Π:可修复件

针对装备使用阶段可修复件的采购优化问题,引入近似拉普拉斯需求概率分布代替正态分布,建立了采购间隔期内的备件短缺函数。根据供应链系统库存控制论,建立了可修备件的采购模型。通过对可修件周转渠道的分析,对采购短缺指标进行了修订,并给出了最优采购点和采购量的计算方法。对两种需求分布下的算例结果进行了对比和分析,结果表明:该模型得到的结果鲁棒性强、偏差小,优化过程简单,为故障率高、消耗量低的可修件采购方案的确定提供了一种新的思路。     

考虑多性能参数的引信弹簧可靠性评估

弹簧作为引信中常用的储能源,是影响引信可靠性的重要零件,而引信失效会形成重大安全隐患。为了准确预估某引信弹簧贮存期间的可靠度变化,提出了一种基于修正Arrhenius模型的多元正态可靠性评估方法。以应力损失率和永久变形率作为性能参数,设计了恒定应力加速退化试验,获取弹簧在120℃、130℃、150℃和160℃下的退化数据,并采用Anderson-Darling统计量验证退化量的最优分布为正态分布。根据修正的Arrhenius方程,得到弹簧在贮存温度下的退化轨迹曲线。基于多元正态分布建立弹簧贮存可靠度模型,分析弹簧贮存期间的可靠度变化特点。通过与其他可靠度模型对比,该模型预估结果更准确,可为引信的视情维修提供依据。     

“It would be impossible to estimate the value of these works...” Mass Production at Springfield Armory during the American Civil War

The U.S. Armory in Springfield, Massachusetts, rarely appears in Civil War histories except perhaps as an unexplained statistical wonder. By late 1863, the Armory was the largest single supplier of rifles to Union forces. Springfield Armory workers out-produced over thirty American contractors, making more Army rifles at less cost while providing contractors with gauges, inspectors, and models, even though there were significant wartime private-sector mechanical innovations. This article identifies and explains the factors in the Armory’s success, provides context on contemporary American arms production and rifle models, and argues that the Armory’s methods and performance were among the first if not the first example of mass production in American small arms manufacture. The relative brevity of the Civil War episode, and the fact that it was not repeated in any comparable way at the Armory until World War II, has obscured its significance in American manufacturing history.     

加速寿命试验下复合失效产品的可靠性评估

产品往往受随机失效和耗损失效两种模式的双重影响,通过构建复合寿命分布模型来表征这类产品失效规律。在加速寿命试验下,基于极大似然估计构造了该类产品寿命参数估计的数值算法;为了验证该寿命分布是否真服从假定的复合分布,构建了常应力等效失效数据的柯尔莫哥诺夫分布检验法;最后,以电连接器这一典型产品为例进行了工程仿真试验并进行数据评估,从而验证了评估方法的正确性。