DC/DC变换器抗辐射试验

文章以ZHDC28S05/18W型数字化DC/DC变换器(额定输入28V,输出5V/3.6A)为例,制定了DC/DC变换器辐射总剂量和单粒子效应试验的方案并进行了摸底试验,根据试验结果更换了集成功率芯片LM2596-ADJ,使产品的抗辐射性能有了明显提高.     

基于商业模式设计的战略性新兴产业发展研究

如何推动我国战略性新兴产业发展是一个热点问题。技术创新是战略性新兴产业发展的重要支撑,然而只有将技术创新与商业模式结合起来,才能真正实现产业化发展。针对产业层面的商业模式设计,提出了技术创新、市场创新、价值网络和赢利模式四个构成要素,并基于商业模式的价值创造、价值传递和价值实现的逻辑过程,而对四个要素的逻辑关系进行了说明。     

Three-dimensional path planning for unmanned aerial vehicle based on interfered fluid dynamical system

This paper proposes a method for planning the three-dimensional path for low-flying unmanned aerial vehicle(UAV) in complex terrain based on interfered fluid dynamical system(IFDS) and the theory of obstacle avoidance by the flowing stream. With no requirement of solutions to fluid equations under complex boundary conditions, the proposed method is suitable for situations with complex terrain and different shapes of obstacles. Firstly, by transforming the mountains, radar and anti-aircraft fire in complex terrain into cylindrical, conical, spherical, parallelepiped obstacles and their combinations, the 3D low-flying path planning problem is turned into solving streamlines for obstacle avoidance by fluid flow. Secondly, on the basis of a unified mathematical expression of typical obstacle shapes including sphere, cylinder, cone and parallelepiped, the modulation matrix for interfered fluid dynamical system is constructed and 3D streamlines around a single obstacle are obtained. Solutions to streamlines with multiple obstacles are then derived using weighted average of the velocity field. Thirdly, extra control force method and virtual obstacle method are proposed to deal with the stagnation point and the case of obstacles’ overlapping respectively. Finally, taking path length and flight height as sub-goals, genetic algorithm(GA) is used to obtain optimal 3D path under the maneuverability constraints of the UAV. Simulation results show that the environmental modeling is simple and the path is smooth and suitable for UAV. Theoretical proof is also presented to show that the proposed method has no effect on the characteristics of fluid avoiding obstacles.     

Semi-analytic Solution of Steady Temperature Fields During Thin Plate Welding

Usually, it is very difficult to find out an analytical solution to thermal conduction problems during high temperature welding. Therefore, as an important numerical approach, the method of lines (MOLs) is introduced to solve the temperature field characterized by high gradients. The basic idea of the method is to semi-discretize the governing equation of the problem into a system of ordinary dif-ferential equations (ODEs) defined on discrete lines by means of the finite difference method, by which the thermal boundary condition with high gradients are directly embodied in formulation. Thus the temperature field can be obtained by solving the ODEs. As a numeri-cal example, the variation of an axisymmetrical temperature field along the plate thickness can be obtained.     

基于XTCE标准的遥测数据处理软件架构研究

XTCE(基于可扩展标记语言的遥测遥控信息交换)数据规范是CCSDS(空间数据系统咨询委员会)发布的空间任务遥测遥控信息描述模型和数据交换格式,旨在为遥测遥控信息定义提供一种标准方式,进而减少遥测数据处理软件支持异构任务的工作量,减少开发成本,缩短开发周期,降低开发风险.本文首先介绍XTCE的整体框架,重点介绍了XTC...     

浅论红色文化产品的创新设计与价值实现——以河北省为例

本文通过对红色文化领域物质与精神两方面产品的研发现状与经验的分析,结合未来设计领域的发展趋势,提出开发体验性和个性化的红色文化产品。以河北省为例,探讨如何在实现红色文化产品的价值同时,更好的使红色文化为当代精神文明建设服务。     

RESEARCH ON DYNAMICAL BEHAVIOR AND DESIGN OF CONTROL PARAMETER FOR NONLINEAR MAGNETIC-CONTROL SYSTEM

Ｍａｇｎｅｔｉｃｌｅｖｉｔａｔｉｏｎｔｅｃｈｎｏｌｏｇｙｉｓａｎａｃｔｉｖｅｓｅｇｒｅｇａｔｅｔｅｃｈｎｏｌｏｇｙ．Ｉｔｉｓｆｉｔｆｏｒｈｉｇｈｓｐｅｅｄｍｏ－ｔｉｏｎ，ｂｅｃａｕｓｅｉｔｉｓｆｒｅｅｏｆｔｈｅｌｉｍｉｔｏｆｄａｍｐｉｎｇｆｏｒｃｅ．...     

伺服系统在烟机电气改造中的应用

小普托卷接机在烟厂中主要用于烟的生产试制,由于原机电气故障频发,维修费用昂贵,致使其无法正常运行,急需改造。改造后的系统采用FX2N PLC、FX2N-4D/A、MR-J2S-A伺服放大器、HC-KFS伺服电机以及F940GOT-SWD-C图形操作终端,实现了对烟支长度的控制。文中介绍了系统硬件组成、参数设定、软件设计以及运行结果。     

多传感器静态数据分配问题的匈牙利解法

多目标多传感器数据关联中的分配问题一直是数据融合领域中的一个关键问题，众多的研究都提出了一系列不同的方法来解决这个NP-hard问题，本文提出了用2维分配问题的匈牙利解法来解决该问题，给出求解2－D，3－D分配的方法，经仿真计算表明，该法能较大程度地降低计算量，是一种实用性很好的方法，同时也值得向更高维的情况作进一步的研究和仿真比较。     

数值模拟技术在钻地武器研制中的应用

系统阐述了数值模拟技术这一新兴手段在钻地武器研制中的主要算法及应用，比较了算法之间的优缺点，介绍了当今流行的各种主要计算程序。作为算例，运用非线性动力有限元LS-DYNA计算程序，对一个防空建筑在弹头侵彻下的动态响应及应力变化情况作了计算，图像形象显示了战斗部在侵彻过程中的形变及其速度，质量随时间的变化情况，最后阐述了数值模拟技术在武器设计等领域的应用。