机载视频摄录装置测试系统的设计

机载摄录装置综合应用了微电子、微处理机、光学等多种技术,测试项目种类多,测试难度大;基于前期对机载摄录装置的研究,设计开发了机载视频摄录装置测试系统,采用了模块化的设计思想,使系统具有较强的扩展性,文中介绍了测试系统的软硬件结构及设计原理,对设计方案的可行性进行了分析;实际应用表明,该测试系统性能稳定,自动化程度高,减少了人为差错,解决了摄录装置的性能检测和维修决策问题,大大提高了机载摄录装置的维护水平.     

基于数据采集的MEMS薄膜材料参数在线测试系统

建立了一套基于数据采集的MEMS薄膜材料参数在线测试系统.该系统包括测试图形,测试信号处理电路及外围附件和专用软件,能自动完成薄膜材料参数的在线测试.测试方法和测试设备简单,能用于工艺线上的在线测试.     

基于PLC和触摸屏的玩具易燃性测试装置

分析了玩具易燃性测试装置的控制要求,提出由PLC和触摸屏组成的控制系统,并就系统的主要硬件配置、软件实现作了详细的阐述.装王运行表明,系统稳定可靠、操作简单、测试效率高、结果准确.     

基于ACO的测试用例预优化及参数影响分析

测试用例预优化是一种先进的软件回归测试用例集优化技术。相比测试用例选择和测试用例集约简技术,它具有更好的灵活性,更容易适应实际软件回归测试过程中的迭代与变化。基于多目标的测试用例预优化技术是当前研究的热点,针对选定的多个优化目标,算法是多目标测试用例集优化的关键。提出了一种基于蚁群优化算法（ant colony optimization,ACO）的多目标测试用例预优化方法,针对平均语句覆盖率和有效执行时间两个优化目标,实现了测试用例集的预优化,并针对多目标解集优劣评价方法进行了改进。同时对蚁群优化算法中的信息素挥发因子ρ、启发因子α和β、蚁群规模m等相关参数对多目标测试用例预优化结果的影响进行了实验分析。实验中使用的被测程序既包括广泛使用的软件测试样本库SIR（software-artifact infrastructure repository）中的程序,也包括Google发布的大规模开源程序JavaScript引擎V8。实验结果表明,当参数α=1,4β6,ρ=0.1时,针对小规模程序,蚁群规模m=32时,算法求得较优解;针对较大规模程序flex和V8,则需要适当增大蚁群的规模以获得较优解集。     

导弹天线罩参数化有限元建模和热可靠性分析

基于Pro/ENGINEER,Patran和MSC Nastran,以坚晶石导弹天线罩为研究对象,结合参数化有限元建模方法,将天线罩结构尺寸、材料性能和热流输入等作为随机因素,使用蒙特卡罗数字模拟法对其进行热可靠性分析,详述参数化建模和可靠性分析的流程,得到天线罩热应力的概率分布、随机因素与热应力的变化关系以及天线罩热可靠度等可靠性分析数据.结果显示,本文的天线罩热可靠度为99.93%.本研究证实对导弹天线罩进行参数化有限元建模和可靠性分析的可行性.     

红外连续变焦镜头的结构设计与热分析

随着红外技术的不断发展,红外连续变焦镜头的应用越来越广泛。为了避免环境温度变化影响红外连续变焦镜头的成像质量,对改变过凸轮的红外镜头进行了光机热分析。建立连续变焦红外镜头的有限元模型,通过热分析对其模型进行处理,完成对有限元模型的热分析,并求解出不同情况下凸轮槽时镜头的位移云图、不同情况下镜片的位移云图、不同角度时凸轮的位移云图和不同角度下镜片的位移云图。结果表明,热光分析方法可以模拟红外光学系统的实际使用情况,并可以预测实际使用条件下的工作条件,对光学系统的设计具有重要的指导意义。     

核电厂最终热阱冷却塔内填料装置的抗震分析和评价

本文采用有限元分析方法对核电厂最终热阱冷却塔内的填料装置结构进行了自重载荷下的静态分析及地震载荷下的动态反应分析,介绍了填料装置的分析方法,各种工况下的载荷组合,建模过程中对模型进行合理简化的方法和评定准则,并给出了按照ASME规范对计算结果进行应力评定的方法。     

星载天线在轨温度场的影响参数分析

为了保证星载天线在轨运行时有较高的热稳定性,就必须对其进行空间环境下的热温度场影响因素分析.通过改变不同的热物理性能参数分别计算温度场,得出在物性参数中影响最大的因素.然后结合工程实际,以铝蜂窝作为天线材料,分别添加不同的热控涂层,最后得出最适合铝蜂窝的涂层,对工程实际具有一定的指导意义.     

综合灵敏度和品质因数的电涡流谐振测量电路参数优化

为提高电涡流传感器的性能,综合考虑了测量灵敏度和回路品质因数两个重要影响因素,研究了其谐振测量电路的参数选择优化方法。在不影响问题性质的前提下,建立了调幅谐振电路的等效简化模型。首先推导了电路阻抗和幅频响应函数的解析式,通过MATLAB数值仿真,分析耦合电阻R0,谐振电容C0对灵敏度影响。其次推导了测量回路的品质因数Q公式,并分析了R0和C0对Q的关系。最后通过实验验证参数取值对测量电路的影响,为电涡流传感器测量电路参数优化选择提供了有效的指导和参考。     

抛光液温控装置结构设计及温度场分析

为精确控制超光滑表面抛光过程中抛光液的温度,根据温控基本原理设计温控装置结构.将用UG建立的温控装置模型导入GAMBIT中进行温度场分析.针对装置内部温度分布不均匀问题,对其结构进行优化：在装置内加入导热隔板将其分为工作区和调温区,制冷器被置于调温区内;将温控装置的外形结构加入过渡圆角.结果表明：优化后的温控装置形成内外环流,工作区温度波动范围为±0.01℃,温度分布均匀对称,满足高精度温控的恒温和匀温要求.     

基于GT-SUITE与Simulink的车辆驱动冷却系统联合仿真分析

为降低纯电动汽车的能耗、提高电池的续航里程,联合GT SUITE与Simulink搭建整车驱动冷却系统和动力系统模型,对某纯电动汽车的热平衡性能进行分析。在所考察工况及电子水泵最大转速条件下,冷却回路最高水温远低于系统设计的温度限值,存在优化空间。通过过程优化,寻找合适的电子水泵转速,在满足系统设计要求的同时,最大限度地减少能耗,为热管理系统控制策略的制定提供参考。     

Iterative learning control of inhomogeneous distributed parameter systems—frequency domain design and analysis

This paper aims to construct a design and analysis framework for iterative learning control of linear inhomogeneous distributed parameter systems (LIDPSs), which may be hyperbolic, parabolic, or elliptic, and include many important physical processes such as diffusion, vibration, heat conduction and wave propagation as special cases. Owing to the system model characteristics, LIDPSs are first reformulated into a matrix form in the Laplace transform domain. Then, through the determination of a fundamental matrix, the transfer function of LIDPS is precisely evaluated in a closed form. The derived transfer function provides the direct input–output relationship of the LIDPS, and thus facilitates the consequent ILC design and convergence analysis in the frequency domain. The proposed control design scheme is able to deal with parametric and non-parametric uncertainties and make full use of the process repetition, while avoid any simplification or discretization for the 3D dynamics of LIDPS in the time, space, and iteration domains. In the end, two illustrative processes are addressed to demonstrate the efficacy of the proposed iterative learning control scheme.     

基于热平衡和结构强度的发动机 分析平台开发及其应用

建立发动机缸体和缸盖的动力学、燃烧和流体有限元模型,进行发动机热平衡、冷却散热和结构强度研究。创建发动机正向设计和分析方法,革新产品开发流程,自主开发热平衡计算平台。建立发动机缸内和水套传热、流体、温度场、强度的计算模型库,设计水套优化方法和流场评价标准,正向计算发动机热平衡和水套散热。通过2个应用案例,证明该平台在发动机热平衡计算和结构分析与评估中的作用。该平台可为发动机热平衡、冷却散热和结构强度的正向设计提供基础。     

Recursive parameter estimation methods and convergence analysis for a special class of nonlinear systems

This paper is concerned with the joint estimation of states and parameters of a special class of nonlinear systems, ie, bilinear systems. The key is to investigate new estimation methods for interactive state and parameter estimation of the considered system based on the interactive estimation theory. Because the system states are unknown, a bilinear state observer is established based on the Kalman filtering principle. Then, the unavailable states are updated by the state observer outputs recursively. Once the state estimates are obtained, the bilinear state observer–based hierarchical stochastic gradient algorithm is developed by using the gradient search. For the purpose of improving the convergence rate and the parameter estimation accuracy, a bilinear state observer–based hierarchical multi‐innovation stochastic gradient algorithm is proposed by expanding a scalar innovation to an innovation vector. The convergence analysis indicates that the parameter estimates can converge to their true values. The numerical example illustrates the effectiveness of the proposed algorithms.     

Conceptual design and simulation analysis of thermal behaviors of TGR blast furnace and oxygen blast furnace

Extensive use of carbon based fuel is the main inducement for global warming and more extreme weather.Reducing carbon dioxide emission and enhancing energy use is a common subject in steel industry.In the integrated steel plant,decreasing carbon dioxide emission must consider energy balance in the whole iron and steel works,and secondary energy must be actively utilized.As promising blast-furnaces,top gas recovery blast furnace(TGR-BF) and oxygen blast furnace have been investigated.In this paper,conceptual...     

隧道照明系统辅助设计与优化分析软件研发

为提高公路隧道照明系统设计的效率和节能水平,基于IESNA LM-62标准的灯具配光数据文件,并以逐点法为照度和亮度计算方法,在VB.net平台中开发面向公路隧道的照明系统辅助设计与优化分析软件.软件包括的功能有:基于车流量、洞外亮度和运行车速的三因素动态调光、各照明区段的长度与亮度分析、灯具回路设计与模式搜索法安装参...     

Steady‐state electro‐thermal analysis and optimization of multilayer boards and substrate‐integrated waveguide filters

An efficient method is proposed to perform the steady‐state thermal analysis of multilayer boards by using the multilayer finite‐difference method to obtain and solve the thermal conductance network. The electro‐thermal analysis of substrate‐integrated waveguide (SIW) filter is further carried out, with its distributed heat source, that is, electromagnetic losses. Then, our method is applied to optimize the electro‐thermal performance of a composite configuration, including a SIW filter with a selfheating chip attached on it. A location with the minimum hotspot temperature is found. Good agreement is achieved between the results simulated with our method and the commercial finite element method (FEM) simulators. When the worst‐case error is set to 5.3%, the run time of our method is significantly reduced by 95% in comparison with the FEM simulators. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:594–604, 2014.     

Global and local heat transfer analysis for bicycle helmets using thermal head manikins

Predicting thermal comfort of protective headgear is of particular interest since the head is one of the most heat-sensitive body parts. Thermal head manikins enable systematic investigation of heat transfer properties of headgear. Such investigation provides valuable inputs for the development of new helmet concepts to improve thermal comfort.This study presents a nine-zone thermal head manikin (9zM) to evaluate local heat transfer effects of headgear. Performance of the new manikin and local data were assessed by comparing with data from a two-zone thermal head manikin (2zM) published previously. Variation for heat flux data was found to be lower for 9zM than for 2zM in tests including convective and radiative heat transfer. The calculation of radiant heat gain revealed similar variation at cranial section for both manikins but it increased at facial section for 9zM. Classification of helmets based on heat transfer data differed for head manikins likely due to slight differences in head geometries. Moreover, local heat transfer data obtained from the 9zM allowed a more detailed investigation of headgear properties. This knowledge contributes to a better understanding of the thermal interaction of head and headgear and, therefore, to a more justified development of optimised headgear designs.