宽温环境下磁光盘瞬态温度场的研究

本文利用有限单元法,在宽温环境(-20℃～+88℃)下,对层状膜结构磁光盘的瞬态温度场进行了模拟,着重分析了环境温度对磁光盘温度场的影响,研究了不同环境温度下磁光盘记录灵敏度同记录光脉冲宽度的关系,为进一步研究宽温环境下磁光盘的热磁记录和磁光读出特性提供了分析手段。     

磁光盘盘温的自动控制和测量系统设计

本文概述了温度对磁光记录特性的影响及盘温测量的重要性,设计出了实现磁光盘有温自动测试和控制的新型系统。该系统集数据采集、数据处理和参数计算等功能于一体,应用软件具有交互性强户界面友好等特点。     

磁光盘录音机及其发展

本文介绍了磁光盘录／放的基本原理原理，简介了ＢＩＲＴＶ‘９７展出的三种磁光盘录音机，展望了磁光盘技术和磁光盘录音机今后的发展。     

Bi代石榴石磁光膜／金属反射层／玻璃多层结构磁光盘的优化设计

从磁光读出和热磁写入两者结合的角度提出一个新的优化目标函数．并用其完成了Ｂｉ代ＤｙＧａＩＧ／金属反射层／玻璃多层结构磁光盘的优化设计。结果表明新优化目标函数更具实际意义。     

磁光盘（MO）发展现状及趋势

叙述了当前国际磁光盘记录介质同发展情况及市场前景，介绍了国内磁光盘产业化情况，提出了发展国内磁光盘产业的建议。     

磁光记录磁畴及其热稳定性研究

磁光存储的原理是热磁记录，信息以磁畴的形式存储于记录介质中。磁畴的形貌及其热稳定性对磁光盘的存储性能有很大影响。报道了ＴｂＦｅＣｏ磁光盘磁畴形貌及其热稳定性的实验研究结果。     

四防磁光盘性能研究报告

磁光盘在盐雾,霉菌,湿热,高低温等环境下工作性能会受到很大影响。文章主要介绍了新研制的四防光盘在盐雾,霉菌,高低温,湿热条件下的抗恶劣环境的工作性能。     

具有磁放大层的高密度磁光盘

具有磁放大层的高密度磁光盘张绍高通常，光盘记录密度的极限取决于记录激光的波长。读出时，如果记录小坑的尺寸小于拾取激光光点的直径时，在激光光点中将会有多于一个以上的小坑，以至使重放信号产生干涉，导致信息读出困难。对于磁光盘，以前也研究出了不受激光波长限...     

中国磁光盘产业的发展

通过比较磁光盘与磁盘，ＣＤ－ＲＯＭ和ＣＤ－Ｒ光盘的主要指标，指出磁光盘的优势和巨大的市场潜力，阐述了磁光盘产业化发展的必要性和可行性，提出了种种设想，以使我国的磁光盘产业迅速走上高速发展展之路。     

磁光记录薄膜磁光特性参数测量的外推方法

本文采用自制的一种磁光特性测试仪器和Romberg外推算法,对于SONY公司的一种640M直接重写磁光盘,在245－350K温度范围内,获得它完整的磁光温度特性,包括克尔角与温度的关系曲线和矫元力与温度的关系曲线,其结果与理论模型仿真的结果一致。     

改善不同环境温度下SiGe HBT热稳定性的技术

提出了发射极非均匀指间距技术以增强多发射极指SiGe HBT在不同环境温度下的热稳定性。通过建立热电反馈模型对采用发射极非均匀指间距技术的SiGe HBT进行热稳定性分析,得到多发射极指上的温度分布。结果表明,与传统的均匀发射极指间距SiGe HBT相比,在相同的环境温度及耗散功率下,采用发射极非均匀指间距技术的SiGe HBT,其最高结温明显降低,热阻显著减小,温度分布更加均匀,有效地提高了多发射极指功率SiGe HBT在不同环境温度下的热稳定性。     

新型无TEC的非制冷IRFPA读出电路研究

为了降低非制冷红外焦平面阵列的功耗，研究了去除热电制冷器（TEC）等温度稳定装置的读出电路。通过对微测辐射热计的电阻温度特性的分析，设计了一种新型无需温度稳定装置的读出电路，该电路的Flash存储器存储不同温度下的校正系数，温度传感器实时检测探测器的环境温度，从Flash中取出相应的温度校正系数送入数模转换器(DAC)，通过DAC的电压输出来控制探测器偏流以进行环境温度补偿。HSPICE模拟结果表明，电路输出与探测器工作的环境温度无关，系统的总功耗下降了80%，同时电路噪声保持在一个较低的水平。     

环境温度影响激光发射二轴转台性能研究

激光发射二轴转台是以转台为主体,承载激光传输及发射功能的设备。转台要求在温度指标范围?40~55 ℃内具有良好的使用性能,为更好地了解环境温度对转台性能的影响,引出了激光发射二轴转台结构,并采用有限单元法对不同环境温度下转台静动态特性进行分析研究,由静力学分析后的转台变形量结果得到环境温度对轴系精度的影响。分析得到,以22 ℃转台性能参数为基准,在温度指标范围内,室温22 ℃时,转台静态特性与轴系精度最优,环境温度偏离22 ℃越远,静态特性与轴系精度越差。当温度每变化10 ℃,转台最大变形量变化约0.529 mm,最大应力值变化约18.418 MPa;方位轴系与俯仰轴系垂直度误差变化约4.715″,方位轴系与底座支撑面垂直度误差变化约4.649″;方位轴系晃动误差变化约0.22″,俯仰轴系晃动误差:(1)温度低于22 ℃,变化约0.33″;(2)温度高于22 ℃,变化约0.569″。转台前6阶模态频率随温度变化具有不同的规律,但频率变化率最大不超过2%。分析结果表明,环境温度对此类转台静态特性与轴系精度影响较大,但对动态特性影响较小,结论与工程经验基本吻合。     

Evaluation of high‐temperature exposure of photovoltaic modules

Photovoltaic (PV) modules operate at temperatures above ambient owing to the thermal energy of sunlight. The operating temperature primarily depends on the ambient temperature, incident sunlight, mounting configuration, packaging configuration, and wind speed. In this paper, the cumulative thermal degradation is modeled to follow Arrhenius behavior. The data are analyzed to determine the constant temperature that would give average aging equivalent to the variable temperatures observed in the field. These equivalent temperatures are calculated for various locations using six configurations, providing a technical basis for defining accelerated thermal‐endurance and ‐degradation testing. This data may also be useful as a starting point for studies of the combined effects of elevated temperature and other factors such as UV, moisture, and mechanical stress. Copyright © 2011 John Wiley & Sons, Ltd.     

Analysis of Phase Characteristics as a Function of Ambient Temperature of IMPATT Amplifiers

Experimental data on phase characteristics as a function of ambient temperatures for GaAs IMPATT amplifiers are presented. An evaluation is given to show the impact of ambient temperature on an amplifier design used in phased-array RADARs.     

油浸式电力变压器内部温度场及其绕组热点的数值计算研究

分析110 kV油浸式电力变压器内部的热量散失过程,并基于有限体积法计算油浸式电力变压器的温度场,通过变压器温度场模型分析判断油浸式电力变压器绕组热点及内部温度场分布情况,为变压器运行维护提供参考。研究表明,不同环境温度下,运行工况的变化对变压器温度场产生的影响是不同的,其内部热点温度和平均温度会随着负载率与环境温度的升高而升高,但热点位置基本不会发生变化。     

Thermal performance modeling of loop heat pipes with flat evaporator for electronics cooling

This work deals with modeling of the thermal performance of a copper-water loop heat pipe (LHP) with a flat evaporator operating in steady state operation. The model is based on steady-state energy and momentum balance equations for each LHP component. Modeling the heat transfer in the evaporator was particularly considered, and the evaporation heat transfer coefficient is determined from a dimensionless correlation which is developed on the basis of experimental data from literature. The validation of this model consists in comparing the experimental results and those obtained by the model for different cooling temperatures. Finally, a parametric study is presented to show the effects of different key parameters such as the radii and the lengths of the liquid and vapor lines, the length of the condenser, the heat sink temperature and heat transfer coefficient as well as the ambient temperature and the heat losses to the ambient.     

Insight into the charge transport and degradation mechanisms in organic transistors operating at elevated temperatures in air

Operational stability of organic devices at above-room-temperatures in ambient environment is of imminent practical importance. In this report, we have investigated the charge transport and degradation mechanisms in pentacene based organic field effect transistors (OFETs) operating in the temperatures ranging from 25 °C to 150 °C under ambient conditions. The thin film characterizations techniques (X-ray photoelectron spectroscopy, X-ray diffraction and atomic force microscopy) were used to establish the structural and chemical stability of pentacene thin films at temperatures up to 150 °C in ambient conditions. The electrical behavior of OFETs varies differently in different temperature bracket. Mobility, at temperatures below 110 °C, is found to be thermally activated in presence of traps and temperature independent in absence of traps. At temperatures above 110 °C mobility degrades due to polymorphism in pentacene or interfacial properties. The degradation of mobility is compensated with the decrease in threshold voltage at high temperatures and OFETs are operational at temperatures as high as 190 °C. 70 °C has been identified as the optimum temperature of operation for our OFETs where both device behavior and material properties are stable enough to ensure sustainable performance.     

数字信号控制器电磁敏感度的环境温度影响研究

针对典型数字信号控制器(Digital Signal Controller, DSC)的电磁兼容问题, 提出了电磁特性与温度特性相结合的分析方法, 研究了环境温度对其传导电磁敏感度的影响.结合电磁敏感度行为级模型结构, 分析了电磁干扰的作用机制, 导出了DSC中金属-氧化物-半导体(Metal-Oxide-Semiconductor, MOS)器件阈值电压和迁移率随环境温度的变化关系;利用直接功率注入与环境温度联合控制技术, 从实验和仿真两个方面分析了模型各部分特征参数在不同温度下的变化, 揭示了电磁敏感度在不同环境温度下变化的内在因素, 并测试了不同温度下典型DSC的电磁敏感度阈值.结果表明, DSC敏感度行为单元中MOS器件阈值电压和迁移率在不同温度下的变化, 会造成其电磁敏感度随环境温度产生显著漂移.