基于虚拟仪器的压力开关测试系统设计

设计了压力开关参数测试系统,能同时实现5个产品的触点接触电阻、绝缘电阻测试,动作压力和恢复压力测试。系统采用虚拟仪器技术,构建了以工控计算机及其板卡为硬件平台,以LabVIEW为软件平台的虚拟仪器测试系统。采用四端钮接法,实现了微电阻的测量,利用继电器逻辑实现了5个产品多参量的自动测试,并能根据测试结果自动判别产品是否合格。结果表明,该系统运行可靠,测试准确度高,测试效率高。     

物伞系统空间运动模式分析

以物伞回收系统为背景,通过理论建模和数值仿真的方法,得出物伞回收系统两种基本空间运动模式（平面摆动和圆锥运动）,分析了其产生原因。利用空投录像验证了文章分析结果,其结论可为工程设计部门提供重要理论参考。     

新型单模光纤模场直径测试系统

介绍了一种新型的单模光纤模场直径测试系统,它采用国际推荐的基准测试方法－远场扫描法,具有测量精度高、速度快、抗干扰能力强和操作简单的特点,既可用于实验室中,也适合在工厂环境下使用,能够替代同类进口产品。     

叶栅风洞计算机测控系统

介绍了以工控机为核心的叶栅风洞测控系统,通过计算机对叶栅风洞实验参数的检测和控制,使叶栅风洞试验系统的性能得到显著提高.     

软件雷达中的总线技术

根据软件雷达开放性的内涵,提出其开放性是以总线及标准的总线接口为基础的,分析了软件雷达对总线资源的要求。讨论了目前的总线技术,给出了一种基于交叉开关网络互联的软件雷达总线结构,并探讨了该结构的特点。     

3000 W IGBT软开关直流稳压电源

为了提高电源效率达到减小能源消耗和热量释放为目的,促进电源技术的革新,文章通过天瑞星公司研制生产的3000W IGBT软开关直流稳压电源为例,论述了零电压开关、零电流开关、零电压零电流开关3种软开关技术的基本思路、概念和工作原理,增进对直流开关电源软开关技术的了解。     

Structural topology optimization under stationary random base acceleration excitations

Structural topology optimization subjected to stationary random base acceleration excitations is investigated in this paper. In the random response analysis, the Large Mass Method(LMM) which attributes artificial large mass values at each driven nodal Degree Of Freedom(DOF) to transforming the base acceleration excitations into force excitations is proposed. The Complete Quadratic Combination(CQC) which is commonly used to calculate the random responses in previous optimization has been proven to be computationally expensive especially for large-scale problems. In order to conquer this difficulty, the Pseudo Excitation Method(PEM) and the combined method of PEM and Mode Acceleration Method(MAM) are adopted into the dynamic topology optimization, and random responses are calculated using these two methods to ascertain a high efficiency over the CQC. A density-based topology optimization method minimizing dynamic responses is then formulated based on the integration of LMM and PEM or the combined method of PEM and MAM. Numerical examples are presented to verify the accuracy of the proposed schemes in dynamic response analysis and the quality of the optimized design in improving dynamic performance.     

取样示波器瞬态响应的光电校准技术研究

本文介绍了一种使用光电方法对取样示波器瞬态响应进行校准的技术。该技术基于飞秒激光和光导开关原理，实现了超快电压脉冲的产生和探测，获得可用于取样示波器校准的信号，之后利用时基修正、抖动修正、反卷积等处理手段，实现了取样示波器瞬态响应的校准。本技术能够获得取样示波器完整的冲激响应和阶跃响应，具有非常重要的意义。     

Thermal behavior of an isolator with mode transition inducing back-pressure of a dual-mode scramjet

Combustion mode transition is a valuable and challenging research area in dual-mode scramjet engines. The thermal behavior of an isolator with mode transition inducing back-pressure is investigated by direct-connect dual-mode scramjet experiments and theoretical analysis. Combustion experiments are conducted under the incoming airflow conditions of total temperature 1270 K and Mach 2. A small increment of the fuel equivalence ratio is scheduled to trigger mode transition. Correspondingly, the variation of the coolant flow rate is very small. Based on the mea-sured wall pressures, the heat-transfer model can quantify the thermal state variation of the engine with active cooling. Compared with the combustor, mode transition has a greater effect on the iso-lator thermal behavior, and it significantly changes the isolator heat-flux and wall temperature. To further study the isolator thermal behavior from flight Mach 4 to Mach 7, a theoretical analysis is carried out. Around the critical point of combustion mode transition, sudden changes of the isola-tor flowfield and thermal state are discussed.     

复合材料连接方法

文中叙述了复合材料常用的几种连接方法,分析了各种连接的破坏模式和连接形式的选择,同时还介绍了国外复合材料连接方法新进展等内容。