Thermal and combustion behavior of Al-MnO2 nanothermite with poly(vinylidene fluoride -co- hexafluoropropylene) energetic binder

Fluoropolymers get increasing attention in energetic materials application due to the high fluorine content. To explore the effect of poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) on Al/MnO2 nanothermite, the samples with different contents are prepared and characterized by SEM, TG-DSC, XRD, and their ignition and combustion behavior are tested and recorded. The results show that P(VDF-HFP) as an energetic binder can combine the nanothermite components together, even exist in the gaps. The integrity of energetic materials has been improved. Thermal analysis shows that the addition of P(VDF-HFP) greatly changes the thermal reaction processes, and the exothermic peaks appear early, but the utilization of fuel and oxidizer is not efficient from the XRD results. Furthermore, the appropriate addition of P(VDF-HFP) can directly reduce the ignition energy threshold and increase the combustion time, which is necessary for the potential ignition charge application. The possible reasons for above phenomena are discussed and analyzed. This research provides a reference for improvement of thermite-based ignition charge formulation.     

非线性控制在磁悬浮系统中的应用

用滑模变结构控制原理设计磁悬浮系统非线性控制器，并在磁悬浮球装置上进行了试验，结果证实这种控制器具有完全的鲁棒性、良好的参数适应性，设计方法也有广泛的适用性。悬浮系统的刚度有显著的提高。     

导弹单发杀伤概率影响因素分析

提出了进行导弹单发杀伤概率影响因素分析的必要性,进行了大量的导弹单发杀伤概率仿真计算,对作战条件和弹目交会条件等重要影响因素进行了深入地分析研究,并对导弹的作战使用、战术决策和目标机的最佳规避机动策略进行了深入探讨。研究成果给飞行员在导弹作战使用过程中进行战术决策提供了强有力的科学理论依据。     

自适应滤波在有源消声中的应用

从分析有源消声的难点出发 ,综述了自适应滤波算法在有源消声中的应用 ,给出了相应的实例 .对自适应滤波在有源消声中应用的未来发展趋势作了展望 .     

An exact branch‐and‐price algorithm for multitasking scheduling on unrelated parallel machines

We consider the multitasking scheduling problem on unrelated parallel machines to minimize the total weighted completion time. In this problem, each machine processes a set of jobs, while the processing of a selected job on a machine may be interrupted by other available jobs scheduled on the same machine but unfinished. To solve this problem, we propose an exact branch‐and‐price algorithm, where the master problem at each search node is solved by a novel column generation scheme, called in‐out column generation, to maintain the stability of the dual variables. We use a greedy heuristic to obtain a set of initial columns to start the in‐out column generation, and a hybrid strategy combining a genetic algorithm and an exact dynamic programming algorithm to solve the pricing subproblems approximately and exactly, respectively. Using randomly generated data, we conduct numerical studies to evaluate the performance of the proposed solution approach. We also examine the effects of multitasking on the scheduling outcomes, with which the decision maker can justify making investments to adopt or avoid multitasking.     

反舰导弹对编队内预定目标捕捉概率研究

基于现代反舰导弹末制导雷达的搜索过程,通过分析反舰导弹对编队内预定目标的捕捉条件,研究反舰导弹对编队内预定目标的捕捉概率计算模型,研究了反舰导弹对编队进行突击时捕捉概率的计算方法,并通过实例计算,得出反舰导弹对编队突击时,突击方向和开机时机等参数的确定方法。     

A two‐echelon inventory‐location problem with service considerations

We study the problem of designing a two‐echelon spare parts inventory system consisting of a central plant and a number of service centers each serving a set of customers with stochastic demand. Processing and storage capacities at both levels of facilities are limited. The manufacturing process is modeled as a queuing system at the plant. The goal is to optimize the base‐stock levels at both echelons, the location of service centers, and the allocation of customers to centers simultaneously, subject to service constraints. A mixed integer nonlinear programming model (MINLP) is formulated to minimize the total expected cost of the system. The problem is NP‐hard and a Lagrangian heuristic is proposed. We present computational results and discuss the trade‐off between cost and service. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009     

澳大利亚维和警察新体制解析

缘于新时期地区安全战略的需要,澳大利亚打造了国际派遣处,建立起了维和警察新体制。该维和警察新体制的运作机制和理念值得关注和学习。澳大利亚希望通过其维和警察新体制扩张并主导在南太平洋地区的警察维和行动。与此同时,澳大利亚在南太平洋地区的强势维和行动面临挑战。     

影响某型高射机枪寿命的镀铬因素分析

本文介绍了某型高射机枪枪管内膛烧蚀破坏的基本过程,然后分析镀铬层质量与使用寿命的关系和镀铬层质量不佳的主要原因,最后提出提高镀铬层质量的有效措施。     

浅谈军用液晶显示器加固技术

本文介绍了常用的军用液晶显示器加固技术,详细说明了热设计、抗振隔冲设计、三防设计和电磁兼容设计等几个关键技术,指出了质量把关的重点。