小型反射镜周边支撑技术

从满足空间光学遥感器反射镜在复杂的工况下综合面形误差要求的角度出发,介绍了小型凸非球面反射镜材料及支撑方式的选择;根据反射镜的定位原理进行反射镜支撑结构的设计;采用CAD/CAE工程分析软件从支撑结构的材料及支撑方式进行分析和优化,设计一种有效的反射镜周边支撑结构,使反射镜面形误差变化量PV值小于λ/10,RMS值小于λ/50（λ=632.8 nm）。最后,测试反射镜在力学环境试验前后的面形变化,证明该结构满足设计要求。     

LTE-A网络中D2D通信的资源分配算法研究

该文研究了D2D通信使用LTE-A网络上行链路的资源分配问题。首先将问题建模为混合整数非线性规划问题(MINLP),其次根据待接入用户对各信道的青睐程度计算特征值列表并形成相应联盟。在保证各用户服务质量(QoS)的情况下,利用最大加权二部图匹配(MWBM)方法为待接入网络用户寻找合适的资源及复用的组合。仿真结果表明,该算法打破了D2D用户在数据传输过程中一直处于专用或者复用模式的束缚,扩大了D2D用户对可选用的资源范围,与现有算法相比,可有效提高系统的总速率。     

基于SAR图像的点状目标检测方法研究

分析了SAR图像目标检测中常用的方差法、恒虚警算法,讨论了对纹理和灰度都敏感的扩展分形法,然后针对弱目标的检测,提出了基于小波多分辨率能级分析的检测方法,最后对四种算法的性能作了比较,并指出了下一步的研究方向.     

高压变频器在山东泰山钢铁集团有限公司的应用

本文介绍了高压变频器在山东泰山钢铁集团有限公司风机、水泵中的改造应用情况,通过对风机、水泵设备变频改造方案的介绍及改造后运行效果的分析,表明钢铁厂风机、水泵变频改造节能效果显著,具有较高的经济效益。     

Thermoelectric Properties of Co-Doped TiS<Subscript>2</Subscript>

The thermoelectric properties of cobalt-doped compounds Co _x Ti_1−x S₂ (0 ≤ x ≤ 0.3) prepared by solid-state reaction were investigated from 5 K to 310 K. It was found that the electric resistivity ρ and absolute thermopower |S| for all the doped compounds decreased significantly with increasing Co content over the whole temperature range investigated. The increased lattice thermal conductivity of the doped compounds would imply enhancement of the acoustic velocity. Moreover, the ZT value of the doped compounds was improved over the whole temperature range investigated, and specifically reached 0.03 at 310 K for Co_0.3Ti_0.7S₂, being about 66% larger than that of TiS₂.     

航天反射镜材料SiC

航天反射镜材料的一些优选性质包括密度低、弹性模量高、热膨胀系数低及热传导率高。与传统光学材料相比,碳化硅(SiC)具有优异的机械和热性能,被认为是引入注目的反射镜材料。本文概述了SiC的基体成形工艺和机械精加工工艺,讨论了其优缺点,并概述了国内外的发展现状。     

Towards thinner and low bowing silicon solar cells: form the boron and aluminum co‐doped back surface field with thinner metallization film

Using thinner wafers can largely reduce the cost of silicon solar cells. One obstacle of using thinner wafers is that few methods can provide good dopant concentration for the back surface field (BSF) and good ohmic contact while generated only in low bowing. In this paper, we have demonstrated the screening–printing B and Al (B/Al) mixture metallization film technique, making use of the screen‐printing technique and the higher solubility of B in silicon to form a B/Al‐BSF. This technique can raise the carrier concentration in the BSF by more than one order of magnitude and reduce the back surface recombination at a low firing temperature (≤800 °C). We have also shown that through the new technique, the metallization paste thickness at the rear could be reduced largely, which however did not degrade the solar cell efficiency. All these efforts are aiming for pushing forward the application of thinner wafers. Copyright © 2011 John Wiley & Sons, Ltd.     

一种网格环境的服务查找算法

网格计算为大规模Internet应用提供了必要的基础架构,服务查找是网格计算的重要研究内容之一。但是目前常见的服务查找算法不太适应于网格环境的分散性和松耦合等特点。提出了一种分布式的、综合考虑网络延迟和节点负载情况及处理能力、适合于网格环境的服务查找算法DDCA。实验结果表明,DDCA算法能有效提高网格环境下应用的整体性能。     

基于HV9910宽电压的自适应温度高亮度频闪灯

设计了一种基于HV9910的自适应温度宽电压范围的高亮度频闪灯,其利用HV9910的宽电压特性,可在10～50 V宽电压范围内高亮度工作。结合HV9910的LD端及二极管的热敏特性,使其根据内部温度变化调节频闪能量,并利用HV9910的内部电源给微功耗的MK6A12P单片机供电,使频闪灯具有过压保护及多种模式工作的功能。     

压电半导体的极化处理及性能研究

极化处理是压电半导体材料制备及构件设计中的关键工艺,直接影响着其压电性能。根据夹层极化的方法,研制出一种多样性极化实验装置,解决了压电半导体的极化问题,并对极化后的GaN材料性能进行了系统研究。实验结果表明:(1)极化使GaN材料具备了压电性能,改变了其力电性能参数;(2)极化显著提高了压电半导体的导电能力,改变了其弯曲强度。