图像匹配中噪声分析和预处理

提出和证明了在三坐标测量机单镜头三维视觉系统中的图像噪声主要有三种：（1）电磁干扰噪声；（2）季节、气候和时间变化引起的噪声；（3）物体的位置和视角变化引起的噪声。相应地提出了一种基于优化图像搜索模块的有效减少和消除噪声的预处理方法。理论分析和实验均表明，该方法具有简便、可靠和速度快的优点。     

填料萃取塔的操作性能及设计计算

系统地介绍了填料抽提塔的两相流动及传质特性，设计计算，对填料塔的设计和操作有一定指导意义。     

由1,4-萘醌催化合成1,4-二烷氧基萘-2,3-二甲腈

研究了以 1 ,4-萘醌为原料 ,通过溴代、氰化和 O-烷基化三步合成 1 ,4-二烷氧基萘 -2 ,3 -二甲腈。在溴代反应中以溴化试剂代替液溴 ;在氰化和 O-烷基化反应中以溴化十二烷基三甲基铵 (DTMAB)和聚乙二醇(PEG)作为相转移催化剂 ,并采用正交设计法考察了相转移催化剂、固体碱、反应温度等因素对反应的影响 ,其中氰化产物收率达 88.7%。     

A novel robust current control approach using adaptive line enhancer for three‐phase current‐source active power filter

An effective system control method is presented for applying a three‐phase current‐source PWM converter with a deadbeat controller to active power filters (APFs). In the shunt‐type configuration, the APF is controlled such that the current drawn by the APF from the utility is equal to the current harmonics and reactive current required for the load. To attain the time‐optimal response of the APF supply current, a two‐dimensional deadbeat control scheme is applied to APF current control. Furthermore, in order to cancel both the delay in the two‐dimensional deadbeat control scheme and the delay in DSP control strategy, an Adaptive Line Enhancer (ALE) is introduced in order to predict the desired value three sampling periods ahead. ALE has another function of bringing robustness to the deadbeat control system. Due to the ALE, settling time is made short in a transient state. On the other hand, total harmonic distortion (THD) of source currents can be minimized compared to the case where ideal identification of the controlled system can be made. The experimental results obtained from the DSP‐based APF are also reported. The compensating ability of this APF is very high in accuracy and responsiveness although the modulation frequency is rather low. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(1): 50–61, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20014     

Variability in stepping direction explains the veering behavior of blind walkers.

Walking without vision results in veering, an inability to maintain a straight path that has important consequences for blind pedestrians. In this study, the authors addressed whether the source of veering in the absence of visual and auditory feedback is better attributed to errors in perceptual encoding or undetected motor error. Three experiments had the following results: No significant differences in the shapes of veering trajectories were found between blind and blindfolded participants; accuracy in detecting curved walking paths was not correlated with simple measures of veering behavior; and explicit perceptual cues to initial walking direction did not reduce veering. The authors present a model that accounts for the major characteristics of participants' veering behavior by postulating 3 independent sources of undetected motor error: initial orientation, consistent biases in step direction, and, most important, variable error in individual steps. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

微波BJT超宽带低噪声放大器的设计

本文给出了一种频带覆盖达１０－１６００ＭＨｚ的微波ＢＪＴ超宽带低噪声放大器的设计方法，从微波ＢＪＴ的噪声模型出发，通过拟合５０Ω源阻抗下微波ＢＪＴ的噪声系数ＮＦ５０和Ｓ参数来提取其噪声参数，然后根据增益，噪声及驻波比要求优化设计放大器，使放大器在超宽带范围内获得平坦增益和低噪声，本文所给出的微波ＢＪＴ惨数提取及放大器优化设计方法已由实验结果所验证。     

基于最小截面差的相位展开

相位展开 (PhU)问题从理论上讲是一个不适定问题。根据被测物理量的整体连续性 ,提出了一种基于最小截面差的相位展开方法。理论分析和对实验条纹图的处理结果表明 ,该方法特别适合于具有相位间断大于π ,条纹欠采样及随机噪声等条纹图的相位展开。同支切 (Branchcuts)法相比 ,该方法具有算法简单、计算量小且可靠度高的特点 ,具有一定的实用性。     

任意型一维FIR数字滤波器设计新方法

本文介绍了一种设计任意型（宽带、窄带、低阶、高阶、低通、高通、带通、带阻）一维FIR数字滤波器新方法．给出设计不同类型滤波器的统一方法。各种类型滤波器脉冲响应的设计公式简单、计算方便。该方法消除了Gibbs现象．不仅克服了优化设计中收敛速度、设计精度及初值选取等问题，而且减少设计高阶滤波器的时间。最后，本文给出了各种类型滤波器设计的仿真结果。     

Nd：MgO：LiNbO3晶体的荧光光谱及其双晶体腔内互倍频实验

采用激光感生荧光技术测量了Ｎｄ：ＭｇＯ：ＬｉＮｂＯ３晶体的偏振荧光光谱，简要地说明了Ｎｄ：ＭｇＯ：ＬｉＮｂＯ３双晶体腔内互倍频的基本原理，并在实验中用染料激光作泵浦源实现了其双晶体腔内互倍频运转；得到５４３ｎｍ横模倍频绿光单端输出约ＹＭＷ，腔前泵浦阈值约３８ＭＷ，总转换效率约为１．３％。     

高频等参数感应(ВИКИЗ)测井技术应用

介绍了高频等参数感应的基本原理。以胜利油田比较典型的 3口井为例 ,详细分析了高频感应资料在划分薄夹层、确定储层流体饱和类型、评价储层电阻率空间分布等方面的应用。研究结果表明 ,高频感应具有极高的纵向分辨率和较好的径向探测特性 ,能够准确计算地层真电阻率、侵入带电阻率及侵入半径 ,通过与常规感应及薄层测井资料的对比 ,论证了高频等参数感应在测井技术应用上的优越性