弹道数据处理融合算法的并行计算

针对参考文献[1]中提出的融合多信源信息的融合算法,讨论了其中大计算量的测元遴选问题,并给出了它的并行算法。最后详细地分析了此并行算法的高效性和可扩展性,给出了加速比的仿真结果     

使用等效偏移角稀疏测量的面阵相机序贯图像几何校正

天基光学相机实际在轨对地观测成像的畸变需通过几何校正抑制。目前主流面阵相机对地观测获得的小尺寸、高帧频序贯图像很难满足传统几何校正方法逐帧解算对单帧图像控制点数量与空域分布的要求且计算量巨大。针对这一问题,提出一种使用等效偏移角稀疏测量的面阵相机序贯观测图像几何校正方法,将逐帧校正参数解算问题转化为时域稀疏测量条件下等效偏移角信号恢复问题,利用等效偏移角信号时频信息可有效降低对单帧图像控制点数量和空域分布要求。通过高分四号卫星面阵相机在轨实测图像数据验证了所提方法的可行性且其能大大降低序贯图像几何校正处理的计算量。     

可压缩流大涡模拟耦合概率密度函数方法中的滤波压力模型

亚格子组分-温度关联项显著影响反应流大涡模拟精度。利用概率密度函数方法中概率等效的特点,发展一种新的滤波压力模型,可以良好封闭亚格子组分-温度关联项。介绍概率密度函数及其耦合求解方法,在已有模型基础上推导建立新的滤波压力模型,并在三维超声速氢气/空气时间发展反应混合层中对不同的滤波压力模型进行数值测试。结果表明,与传统的滤波压力模型相比,新的滤波压力模型可以明显改善反应混合层的模拟准确度。特别地,基于新的滤波压力模型,大涡模拟耦合概率密度函数方法可以较好地模拟链式反应中间微小组分如超氧化氢基等,有望更有效地再现自点火等复杂现象。     

相干反斯托克斯喇曼光谱测量技术

根据燃烧诊断的需要 ,研究了理论相干反斯托克斯喇曼光谱 (CARS)与温度、浓度和压力的关系 ,在液化石油气 /空气预混火焰中进行了氮分子CARS测温实验。结果表明 ,CARS是一种很有前途的发动机燃烧诊断技术     

铅壳柔爆索爆炸产生冲量的实验

采用光电测量方法 ,对铅壳柔爆索爆炸产生的冲量进行了实验测量。实验结果表明 ,打击到靶板表面的铅粒子中仅有一小部分粘附在靶面上 ,相邻柔爆索之间的相互作用使得冲量增大     

一种强度补偿反射式光纤位移传感器的研究

:提出一种等间距排列的三探头反射式光纤位移传感器 ,该传感器通过双路接收的方法来实现光强补偿。从理论上对该种传感器的补偿机理作了详细的分析 ,得出了位移特性调制函数的表达式 ,给出了仿真曲线。结果表明 ,这种光纤传感器可以有效地消除因光源光强波动、表面反射率以及光纤传输损耗的改变对输出特性的影响     

基于尺度空间理论的多门限化技术

本文基于尺度空间理论提出了两种多门限化方法：第一种新方法先由精到粗求直方图在不同尺度下的表征,再由粗到精校正定位,最后由生命期长短来确定门限;第二种方法首先在一粗尺度上找特征结构,再由粗到精“聚焦”到最精尺度上获取门限。两方法克服了以往一般门限法的若干缺陷,不仅定位准确,而且普适性强。实验证明新方法是令人满意的。     

国外铣削刀具磨损量自动检测方法综述

综述了国外现有的铣削刀具磨损量自动检测方法,对比分析了各方法的优缺点及应用范围,并对其在我国军品生产中的应用前景进行了初步分析。     

Benders' cuts guided large neighborhood search for the traveling umpire problem

This article introduces the use of Benders' cuts to guide a large neighborhood search to solve the traveling umpire problem, a sports scheduling problem inspired by the real‐life needs of the officials of a sports league. At each time slot, a greedy matching heuristic is used to construct a schedule. When an infeasibility is recognized first a single step backtracking is tried to resolve the infeasibility. If unsuccessful, Benders' cuts are generated to guide a large neighborhood search to ensure feasibility and to improve the solution. Realizing the inherent symmetry present in the problem, a large family of cuts are generated and their effectiveness is tested. The resulting approach is able to find better solutions to many instances of this problem. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

Periodic review inventory management with contingent use of two freight modes with fixed costs

We study a stochastic inventory model of a firm that periodically orders a product from a make‐to‐order manufacturer. Orders can be shipped by a combination of two freight modes that differ in lead‐times and costs, although orders are not allowed to cross. Placing an order as well as each use of each freight mode has a fixed and a quantity proportional cost. The decision of how to allocate units between the two freight modes utilizes information about demand during the completion of manufacturing. We derive the optimal freight mode allocation policy, and show that the optimal policy for placing orders is not an (s,S) policy in general. We provide tight bounds for the optimal policy that can be calculated by solving single period problems. Our analysis enables insights into the structure of the optimal policy specifying the conditions under which it simplifies to an (s,S) policy. We characterize the best (s,S) policy for our model, and through extensive numerical investigation show that its performance is comparable with the optimal policy in most cases. Our numerical study also sheds light on the benefits of the dual freight model over the single freight models. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011