Robust protein microarray image segmentation using improved seeded region growing algorithm

Protein microarray technology has recently emerged as a powerful tool for biomedical research. Before automatic analysis the protein microarray images, protein spots in the images must be determined appropriately by spot segmentation algorithm. In this paper, an improved seeded region growing (ISRG) algorithm for protein microarray segmentation is presented, the seeds are obtained by finding the positions of the printed spots, and the protein spot regions are grown through these seeds. The experiment results show that the presented algorithm is accurate for adaptive shape segmentation and robust for protein microarray images contaminated by noise.     

InGaAsP SBH激光器光束质量的非傍轴分析

计算了InGaAsPSBH激光器的TE₀₀模,并利用非傍轴矢量矩理论,分析了平行于p-n结方向上的光学质量因子M_y²在以往有关M²的计算中,往往忽略了包层中光场的贡献,因此得出M²小于1的结论当半导体激光器的激活层的尺寸远小于发射波长时,大部分光场将渗透到包层中,因此,包层的光场是不能忽略的考虑到激活层和包层中的光场对M²的影响,给出了非傍轴半导体激光M²的精确表达式结果表明,M_y大于1.     

Cross-talk correction in dual-labeled fluorescent microarray scanning

Cross-talk phenomenon in dual-labeled fluorescent microarray scanning is analyzed from cross-excitation and cross-emission. It is turned out that the spectral overlap of the fluorophores is crucial for cross-talk error, and this error can be corrected by an image subtraction method. The experiment was successfully applied to separate the Cy3 channel and the Cy5 channel in microarray scanning. The cross-talk error was reduced from more than 1% to about 0.1%.     

DNA测序信号去噪分析的一种新方法

在DNA荧光测序中,噪声会影响分析的准确度和检出限。相比其他滤波方法,小波分析具有良好的时频域分辨特性。在小波去噪处理中,正确选择合适的小波基函数、去噪阈值和分解层数直接关系到信号去噪处理的质量。为了真实构建噪声模型并准确评价去噪算法的有效性,实验中通过实际系统中采集到的噪声信号叠加理想荧光信号构建DNA测序仿真信号,去噪分析的结果表明：选择sym7小波基函数、分解层数(lev＝5)与使用固定格式软阈值,有效去除了DNA测序信号的噪声;处理后,信号的信噪比提高了5倍以上。将其用于处理实际的DNA电泳荧光信号,相比基于随机噪声模型的算法,去噪后的信号更加真实可靠。     

用于提高种子注入Nd：YAG激光器性能的一种光学补偿方法的设计计算

分析了利用干涉法实现腔模锁定的种子激光器的工作原理，在此基础上提出了偏转检测器法补偿由于信号处理可引起的滞后，为种子注入激光器的腔模锁定技术的提供了新的改进方法，可方便而有效地控制从振荡器的输出光质。     

四界面谐振反射器的选模特性

本文运用分层媒质特征矩阵给出了不敷反射膜的四界面谐振反射器的“波长-反射率”的理论计算公式,分析了四界面谐振反射器的“波长-反射率”和波长扫描特性.为四界面谐振反射器的设计和应用提供了一种可靠的理论计算方法.     

Determination of human skin optical properties in vivo from reflectance spectroscopic measurements

A novel approach has been proved to quickly and non-invasively determine the optical properties of human skin in vivo. It is based on the diffuse reflectance approximation model and subjected to the well established library of absorption spectra of water and hemoglobin. Under the nonlinear least-square algorithm, fitting the measured spectra in the range of 400-1000 nm to the diffusion approximation model, the reduced scattering coefficient and absorption coefficient of skin tissue can be quickly determined in vivo. The results show that this method is convenient and suitable for the real-time clinical application.     

小型化望远式激光共焦扫描显微内窥镜

研制了一种激光共焦扫描显微内窥镜,采用望近式显微内窥光学系统,同时实现长距离的图像中继传输、远心f-theta光学扫描和显微内窥成像功能.二维共焦扫描由双振镜实现,低噪音扫描控制信号由嵌入式系统产生.为实现便携式应用,激光共焦扫描显微内窥镜采用小型化设计方案.首先,体内的显微内窥成像光学系统,外径尺寸为8 mm,工作长...     

色散、群速与群折射率

本文讨论了群折射率存在的物理意义,指出群折射率不仅包含了折射率概念而且还体现了折射率的色散性质,同样能作为材料本身的光学性质参量.接着指出在折射率的白光干涉法测量中存在着忽视色散作用而导致的将群折射率误认为折射率的情况.将群折射率与折射率区别开来,不仅可以消除折射率测量中所存在的错误,而且可以突出色散现象在光传播时间特性上的意义.为此建立了折射率与群折射率的相互变换关系,通过对于典型物质的折射率与群折射率变换关系的计算,说明二者在数值上的差别甚至对于气体介质来说也是不能忽略的.     

激光技术在武器系统中的应用

根据大量详实的战争技术资料,介绍激光测距机、激光制导武器及激光定向能武器在武器系统中的作用、应用现状及发展趋势,从而阐明现代战争的主要特点是快速、昼夜全天候作战和远距离攻击目标命中率高,以达到远离本土打赢任何一场局部战争的目的.