弱导光纤的标量衍射光束特性分析

仿照罗兰圆光学系统构造罗兰球光学系统 ,在罗兰球中简化电磁波的瑞利 索末菲标量衍射积分公式 ,推导出折射率阶跃分布的弱导光纤LP模衍射场分布和空间频谱的计算公式。提出LP0 1模远场衍射分布存在类似于平面波圆孔夫琅禾费衍射艾里斑的中央亮斑概念 ,并给出中央亮斑角半宽度的计算公式。     

A Detection-Theoretic Model of Echo Inhibition.

A detection-theoretic analysis of the auditory localization of dual-impulse stimuli is described, and a model for the processing of spatial cues in the echo pulse is developed. Although for over 50 years "echo suppression" has been the topic of intense theoretical and empirical study within the hearing sciences, only a rudimentary understanding of its mechanisms has emerged. In this article, psychometric functions and results from matching studies are used in developing a model that specifies the perceived position of the echo pulse as a normal deviate, with an expectation that is a logistic function of the echo delay and a variance that depends on interaural time difference. Loss of information in the echo event is quantified as a decline in the efficiency with which the binaural system receives information from the lag impulse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

利用机载SAR图像仿真星载SAR图像

简要介绍了现有的SAR图像仿真方法,提出了一种利用机载SAR图像进行星载SAR图像仿真的方法,对仿真原理进行了阐述,着重研究了图像几何特性、空间分辨率、噪声特性、辐射特性仿真的数学模型及设计流程,最后进行了计算机仿真。结果分析表明得到的仿真图像具有较高的逼真度,该星载SAR图像仿真方法是有效的。     

部分样本雷达信号的参数估计

线性调频信号参数检测是SAR对抗的一个重要问题 ,其估计参数的方法有多种 ,但对于分析部分样本LFM信号而言 ,绝大多数估计方法的误差很大。在用快速相关解线调估计和分析部分样本LFM信号存有误差的基础上 ,提出了一种改进的快速相关解线调算法运用于部分样本LFM信号的起始频率和调频斜率参数的估计 ,减小了误差。最后对改进的算法进行了仿真 ,证实了改进后的有效性。     

Hemispheric contributions to nonverbal abstract reasoning and problem solving.

Hemispheric involvement in reasoning abilities has been debated for some time, and it remains unclear whether the right hemisphere's involvement in problem solving is modality specific or dependent on the type of spatial reasoning required. In the current study, 2 types of nonverbal reasoning abilities were examined, spatial reasoning and proportional reasoning, in 109 patients with cerebrovascular disease that was confined to either the right or the left hemisphere or was diffuse in nature. Results indicated that no lateralizing effects were present based on type of spatial reasoning. Findings are consistent with the suggestion that higher order cognitive processes involved in nonverbal abstraction and problem solving are not strongly lateralized to the right hemisphere but rather are more generally distributed throughout the cortex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于多分辨率的图象压缩系统结构分析

本文着重对图象多分辨率技术进行分析，并提出了相应的系统结构成框架，同时还探讨了以图象多分辨率处理为核心，采用了 新的压缩编码的可能性。     

Projection center calibration by motion

Camera calibration is the first step of three-dimensional machine vision. A fundamental parameter to be calibrated is the position of the camera projection center with respect to the image plane. This paper presents a method for the computation of the projection center position using images of a translating rigid object, taken by the camera itself.

Many works have been proposed in literature to solve the calibration problem, but this method has several desirable features. The projection center position is computed directly, independently of all other camera parameters. The dimensions and position of the object used for calibration can be completely unknown.

This method is based on a geometric relation between the projection center and the focus of expansion. The use of this property enables the problem to be split into two parts. First a suitable number of focuses of expansion are computed from the images of the translating object. Then the focuses of expansion are taken as landmarks to build a spatial back triangulation problem, the solution of which gives the projection center position.     

智能型逆变式恒电位仪

介绍了一种以ＩＧＢＴ为逆变器件的智能型逆变式恒电位仪的结构和工作原理。提出了由电位和电流双环控制、脉宽调制与脉频调制相结合的控制方法。还介绍了以单片机为核心组成的智能测控单元的结构和原理。试验表明，所研制的新型恒电位仪具有效率高、体积小、重量轻、功能全、安装使用方便等优点。     

强激光的时间整形和空间整形——利用双折射透镜组实现激光束的空间整形

本文使用琼斯矩阵方法对双折射透镜组空间整形系统的光强透射率分布和工作特性进行了分析,并讨论了工程设计中参数的选择以及加工误差带来的影响等有关问题.     

分析卤化银微晶的EDS方法探讨

本文探讨了用Ｘ射线能谱仪（ＥＤＳ）分析卤化银微晶的空间分辨率和吸收修正问题。对ＳＥＭ－ＥＤＳ和ＳＴＥＭ－ＥＤＳ两种不同分析模式的空间分辨率进行计算，表明ＳＴＥＭ－ＥＤＳ是研究单个卤化银微晶内碘的含量及分布的有效方法。并对定量分析数据和吸收修正参数进行了讨论，结果证明微晶不同区域厚度的差异，对碘含量的定量测定的影响可以忽略。