采用Ti/TiW/Au栅制作Si衬底上CaAs MESFET与集成电路

本文从制备硅集成电路(SiIc)与砷化镓集成电路(GaAs IC)单片兼容电路的要求出发,提出了Ti/TiW/Au肖特基金属化结构,制备出了性能良好的Ti/TiW/Au栅Si衬底上分子束外延(MBE)的GaAsMESFET与GaAs IC。     

介绍两种画中画插入播出器

介绍画中画插入播出器的工作原理及设计思想，并给出了实际的电原理图。     

Tensile, creep, and ABI tests on sn5%sb solder for mechanical property evaluation

Sn5%Sb is one of the materials considered for replacing lead containing alloys for soldering in electronic packaging. We evaluated the tensile properties of the bulk material at varied strain-rates and temperatures (to 473K) to determine the underlying deformation mechanisms. Stress exponents of about three and seven were observed at low and high stresses, respectively, and very low activation energies for creep (about 16.7 and 37.7 kJ/mole) were noted. A maximum ductility of about 350% was noted at ambient temperature. Creep tests performed in the same temperature regime also showed two distinct regions, albeit with slightly different exponents (three and five) and activation energy (about 54.4 kJ/mole). Ball indentation tests were performed on the shoulder portions of the creep samples (prior to creep tests) using a Stress-Strain Microprobe^@ (Advanced Technology Corporation) at varied indentation rates (strain-rates). The automated ball indentation (ABI) data were at relatively high strain-rates; however, they were in excellent agreement with creep data, while both these results deviated from the tensile test data. Work is planned to perform creep at high stresses at ambient and extend ABI tests to elevated temperatures.     

地下三维目标电磁散射特性研究

本文推出集总电阻加载圆柱形天线在时域有限差分（FD-TD）法中的计算公式。对Mur二阶吸收边界条件在三维FD-TD法计算中的稳定性进行了研究，提出保证Mur二阶吸收边界条件稳定所必须注意的问题。在集总电阻加载圆柱形天线激励下，对色激媒质中三维目标的瞬态电磁散射特性进行了计算和分析，并将部分计算结果与实验测试的结果进行了比较，二者具有比较好的一致性。研究了色散媒质和目标特性对目标回波信号的影响，并对有耗媒质中细导线型目标的瞬态散射机理进行了分析。     

圆锥形零件冲压变形与成形载荷的分析

由于悬空侧壁部分的变形状态是圆锥形零件成形的关键，而径向拉应力是实现悬空部分成形的必要条件，同时也是该部分冲压成形成败的关键为此，经力学分析得出了侧壁部分径向拉应力的解析式和造成圆锥形零件破裂的最大径向拉应力的计算式。同时分析了圆锥形零件的成形载荷。     

导电衬垫材料的研究与发展

导电衬垫材料是电子设备中应用最为广泛的一类屏蔽材料，在抑制电子设备缝隙电磁泄漏方面发挥了重要作用。文章结合作者的科研工作，对于衬垫材料的抑制机理、材料类型、屏蔽特性、屏效计算、应用技术、测试方法等关键技术进行了综述，并提出了将来研究发展的方向。     

Performance of SBR-Modified Asphalt Yufeng Cong

A dose of SBR modifier added to asphalt can improve asphalt's performance in stability, permanence, viscosity, and resistance to aging. Better application performances of asphalt pavement are affected directly by proper SBR modifying. This paper shows some investigations that confirm the relationship between the addition of SBR with the structure and the properties of SBR-modified asphalt. This paper also discusses the modified asphalt high temperature property, low temperature ductility, and mechanism of SBR-modified asphalt. The addition of SBR modifier showed an increase in viscosity, softening point, and elastic recovery of modified asphalt with rising temperature. When the temperature rises, the improvement of SBR-modified asphalt in softening point, elastic recovery, and visco-toughness result from SBR cross-linking. Although the lengths of low temperature ductility of SBR-modified asphalt are increased, the viscosities of modified asphalt increase; however, the softening point between the upper layer and lower layer were about 1.8°C after the isolated experiment.     

台西南盆地中新生界石油地质与油气勘探前景

台西南盆地是南海北部大陆架东区边缘盆地链上的中、新生代含油气盆地之一,与其西边的珠江口盆地相邻,处在中国近海陆架盆地天然气富集区带的有利位置,具有良好油气资源潜力和勘探前景。该盆地由北部凹陷、南部凹陷及中央隆起带等3个构造单元所组成。迄今为止,其勘探及研究程度较低,仅在中央隆起带中部勘探中发现了CFC、CFS及CGF等渐新统砂岩及中生界白垩系裂缝性储集层之含油气构造,且探井及研究亦主要集中于该区,其他区域则勘探及研究均十分薄弱。由于中央隆起带处在盆地中部区域上有利油气运聚的低势区,具有良好的油气运聚成藏条件,故迄今勘探发现的商业性油气均集中于该带,因此处于两凹之隆之中央隆起带应是该区最佳的油气富集区带及远景区,而加大勘探力度、全面解剖中央隆起带、深入研究其油气富集规律,则应是台西南盆地尽快获得油气勘探突破之关键。     

基于智能优化相关向量机的综合传动变工况直驶传递效率预测

传递效率是表征履带车辆综合传动装置性能的重要指标之一,但综合传动装置内部复杂的动力传递路径和外部工作环境导致其传递效率预测模型建模困难,无法保证传递效率的准确计算。基于上述分析,提出一种基于综合传动装置直驶模式下多种工况传递效率数据驱动的传递效率预测方法。对75台综合传动装置不同工况下的传递效率数据进行统计分析并得到统计特征;通过统计特征选择智能优化相关向量机进行传递效率预测建模,进而实现待测综合传动装置在变工况直驶模式下的传递效率预测。结果表明,变工况下测试样本传递效率预测结果的平均绝对误差和均方根误差分别控制在0.01和0.02以内,验证了该方法的可行性和正确性。     

贴片机工作性能检测参数

设备制造商和用户对于贴片机性能的衡量采用相同的评估标准,对达成买卖双方统一的认识是非常重要的。针对这种情况,将贴片机的性能参数规范化、标准化可以满足交易双方的需求,并能达到评判机器贴装能力的行业共识。