Force chains based mesoscale simulation on the dynamic response of Al-PTFE granular composites

Force chains based mesoscale simulation is conducted to investigate the response behavior of aluminum-polytetrafluoroethylene (Al-PTFE) granular composites under a low-velocity impact. A two-dimensional model followed the randomly normal distribution of real Al particles size is developed. The dynamic compressive process of Al-PTFE composites with varied Al mass fraction is simulated and validated against the experiments. The results indicate that, force chains behavior governed by the number and the size of agglomerated Al particles, significantly affects the impact response of the material. The failure mode of the material evolves from shear failure of matrix to debonding failure of particles with increasing density. A high crack area of the material is critical mechanism to arouse the initiation re-action. The damage maintained by force chains during large plastic strain builds up more local stresses concentration to enhance a possible reaction performance. In addition, simulation is performed with identical mass fraction but various Al size distribution to explore the effects of size centralization and dispersion on the mechanical properties of materials. It is found that smaller sized Al particle of com-posites are more preferred than its bulky material in ultimate strength. Increasing dispersed degree is facilitated to create stable force chains in samples with comparable particle number. The simulation studies provide further insights into the plastic deformation, failure mechanism, and possible energy release capacity for Al-PTFE composites, which is helpful for further design and application of reactive materials.     

A method to determine the shell layout scheme for equipment battlefield damage tests under artillery fire

In this paper,a new method for determining the shell layout scheme is proposed,which can make the equipment damage data by the battlefield damage test resemble as close as possible the actual combat data.This method is based on the analysis of the impact point distribution and effective damage area of equipment.In order to obtain the position of the impact points,an impact point distribution model under artillery fire was established.Similarly,in order to obtain the effective damage area of equipment,the concepts of generalized damage area and task-based equipment functional damage probability were demonstrated,and the corresponding calculation model was established.Through case analysis,the shell layout scheme was effectively obtained,verifying the correctness of the proposed method.     

孙子兵法的研究成果及发展方向

《孙子兵法》研究在现实应用方面取得了丰硕成果:学术界充分肯定并深入探讨了其中所蕴含的追求和平的大智慧,高度重视它对国家安全的启示并借助其独特视角把握当今世界的安全问题,对它提出的一系列战争指导原则在信息时代具有的重要价值作了有益探索。加强对《孙子兵法》的研究应该抱着实事求是的科学态度,努力把握《孙子兵法》的思想精髓,全面把握其思想体系,注重学习和领会其朴素辩证的思维方法。     

采用遗传算法的电控增压器电磁阀优化设计

运用Ansoft Maxwell软件建立电磁阀的动态响应特性仿真模型，并通过试验验证模型的准确性。利用模型集成ISIGHT软件的方法，对影响电磁阀动态响应特性的参数进行灵敏度分析，得出各个参数对动态响应特性的Pareto图。基于遗传算法对电磁阀进行多参数优化设计，获取最佳参数组合，并利用电磁阀动态响应特性试验台架，开展参数优化前后电磁阀动态响应特性的对比试验研究。试验结果表明：相比于原参数方案，参数优化后的电磁阀动态响应特性得到大幅度提升，其开启响应时间缩短了59.1%，关闭响应时间缩短了47.2%。     

火炮连续射击过程中对动态误差变化的补偿方法研究

阐述了火炮在连续射击过程中,由于系统转动惯量的变化,会产生很大的负载力矩,对系统产生一系列的冲击,影响了系统的射击精度与稳定性.分析了动态误差产生的主要原因,并提出了通过对干扰力矩进行补偿来提高性能的方案.仿真结果表明了该补偿方法的有效性和可行性.     

ITSON：一种基于拓扑演化的P2P智能搜索机制

P2P系统中节点的动态特性对搜索性能的稳定提出了很大挑战。借鉴社会学和组织学相应原理,提出拓扑演化模型捕获节点的运动规律。节点模拟人类在社会网络中的行为,根据自身和他人的兴趣变化,随搜索过程的进行,利用自身局部信息,动态、自适应地调整网络拓扑,及时反映资源分布以及搜索内容的动态变化,维持资源合理组织。在此基础上提出的智能搜索机制ITSON(InTelligent Search based on tOpology evolutioN),利用消息转发的智能性进行路由方向决策,从而迅速定位资源提供节点。仿真结果说明,ITSON能自动优化网络,具有良好的搜索性能和自适应特性。     

浅析军代表处理质量问题的一般程序

本文按照质量问题双归零的原则,从发现问题、分析问题、解决问题三个方面对军品质量问题处理的程序进行了分析,归纳出了六个解决问题的一般步骤,以求为当前军代表处理质量问题提供一些借鉴。     

关于公安消防部队信息化建设整体规划的思考

对公安消防部队信息化建设的总体目标、建设思路、现状、发展战略重点及保障措施等方面提出了基本看法。     

谐振子的下降和上升算符的一种函数关系和它的应用

在量子力学中求解含时谐振子问题时,谐振子的下降和上升算符的几个特殊形式的计算起着关键作用,但传统的计算方法比较烦琐。笔者从量子力学的一个常用公式推导了一个相关的谐振子的下降和上升算符的一种函数关系,并将这个关系应用到具体问题当中,使得计算得到了简化。     

建筑工程消防安全管理改革的理论研究

以现代管理学的视角,运用系统论、信息论和控制论的基本原理,对建筑工程消防安全管理改革的理论基础进行了初步研究,分析了新时期建筑消防管理的特点和地位,提出了改革建筑消防管理模式的要点,讨论了建筑消防管理改革的实施,构筑了新的建筑消防管理模式的基本框架。