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A Separating Algorithm for Overlapping Cell Images  [PDF]
Jinping Fan, Yonglin Zhang, Ruichun Wang, Shiguo Li
Journal of Software Engineering and Applications (JSEA) , 2013, DOI: 10.4236/jsea.2013.64023
Abstract:

The cell overlapping and adhesion phenomenon often exists in cell image processing. Separating overlapped cell into single ones is of great important and difficult in cell image quantitative analysis and automatic recognition. In this paper, an algorithm based on concave region extraction and erosion limit has been proposed to judge and separate overlapping cell images. Experimental results show that the proposed algorithm has a good separation effects on analog cell images. Then the method is applying in actual cervical cell image and obtains good separation result.

矩形元件离焦及像散计算方法  [PDF]
高波,徐凯源,柴立群,李强,魏小红,刘昂
强激光与粒子束 , 2011,
Abstract: ?利用zernike多项式进行最小二乘拟合来计算矩形元件的离焦及像散,不需要波面数据在圆域内正交,从而避免了波面数据缺失区域的数据插值。通过计算圆形口径数据,与商业软件计算结果比较,差别小于0.005倍波长,证明了该方法计算离焦及像散的可行性。分析了不同长宽比下矩形元件的离焦及像散。结果表明用商业软件计算矩形口径元件像散时,随着长宽比的增加,偏差会明显增大。
基于地球椭球的离轴式双线阵相机像移补偿  [PDF]
武星星,刘金国,孔德柱,张立平,龙科慧
红外与激光工程 , 2014,
Abstract: 离轴反射式双线阵立体测绘相机的视轴和光轴分离,由于地球为椭球体,视轴和光轴对应的地物点的距离随星下点与升交点的地心角而变化。而成像传感器与光轴垂直,对视轴对应的地物点成像,这些因素导致离轴反射式双线阵立体测绘相机的像移速度和偏流角随离轴角等变化。在对离轴反射式空间相机的成像原理进行分析的基础上建立其等效简化模型,推导了基于地球椭球的离轴反射式双线阵立体测绘相机的像移速度和偏流角计算公式。并以某离轴反射式双线阵立体测绘相机为例,对正视相机和后视相机统一调整行周期与偏流角对成像质量的影响进行分析。分析结果表明,以调制传递函数下降不超过5%为约束,当积分级数大于4时应分别调整正视相机和后视相机的行周期。统一调整偏流角时应以正视相机和后视相机偏流角的均值为准,积分级数应取89以内。
Study of the Relationship Between Nonlinearity of CCD and Frequency Overlapping
CCD的非线性与频谱混叠的关系研究

QIAO Nao-sheng,CAI Xin-hua,PENG Guang-han,
乔闹生
,蔡新华,彭光含

光子学报 , 2007,
Abstract: The overlapping spectrum caused by the nonlinearity of CCD was analyzed,and the way of reducing overlapping spectrum was presented.The cause to high order spectrum produced by the nonlinearity of CCD was analyzed through theory.The simple physical explain and analytical deduction was given,and also results of overlapping spectrum were given through simulation of computer and experiment.The results of simulation of computer show that the measurement precision of FTP can be improved obviously by denser sampling.
几何校正对暗像元算法及离水辐亮度反演精度的影响:以太湖为例  [PDF]
陈军,付军,孙记红
湖泊科学 , 2011, DOI: 10.18307/2011.0114
Abstract: 几何校正将引起几何校正前后像元的像素值发生变化,进而导致暗像元的辐亮度在几何校正前后存在偏差.本文以太湖为研究水区,以2003年10月28日的Landsat/TM影像、2008年7月24日的CBERS影像和2009年4月25日的HJ-1B影像作为数据基础,研究与探讨了几何校正对暗像元大气校正算法以及离水辐亮度反演精度的影响.通过本文的研究可知,几何校正将引起Landsat数据、CBERS数据和HJ-lB数据的暗像元辐亮度存在0.2,0.47和0.882W/(m2·sr·μm)的绝对偏差;对于上述三景数据,几何校正将引起3.28%-9.81%的基于暗像元方法的气溶胶光学厚度估算偏差;几何校正对基于Landsat/TM影像数据和CBERS影像数据的离水辐亮度反演精度影响相对较小,其误差主要为0-6%,对基于HJ-1B卫星数据的离水辐亮度反演精度的影响相对较大,其误差主要为0-15%,局部区域可达40%以上.因此,大气校正必须在几何校正之前进行处理。
数字离轴全息实验系统及其零级像分析  [PDF]
吕且妮,葛宝臻,张以谟
天津大学学报(自然科学与工程技术版) , 2005,
Abstract: 针对数字全息术中记录介质分辨率制约物参光的最大夹角给实验系统搭建带来的问题,提出一种数字离轴全息记录系统.该系统是将低频全息衍射光栅作为分光元件引入数字全息系统,利用光栅衍射的0级和+1/-1级形成离轴全息记录光路,同时对再现像中零级进行了理论分析,并进行实验研究.实验结果证明了该系统的可行性,并且具有光路系统简单、操作容易等特点.
Analysis of the fully destructive interference of overlapping-images in MMI couplers
多模干涉耦合器中重叠像相干相消现象分析

Sun Yi-Ling,Pan Jian-Xia,
孙一翎
,潘剑侠

物理学报 , 2007,
Abstract: Based on self-imaging effect and overlapping-imaging properties of multimode interference couplers, the phenomenon of fully destructive interference of overlapping-images in MMI couplers is revealed, for the first time. The condition for overlapping-image fully destructive interference is derived. From the point of view of overlapping-image fully destructive interference, we explain the paired interference and the symmetric interference. The expressions of the positions and number of output images for two especial overlapping-images are also given. We prove that this kind of phenomena exists not only in the paired interference and the symmetric interference by way of an example. The influence of the positional number on the fully destructive interference images is also analyzed. And the guided-mode propagation analysis method is used to confirm the analytical results.
On separability and separating method of nonlinear mixed signals
非线性混叠信号的可分离性及分离方法研究

Liu Ju,Nie Kaibao,He Zhenya,
刘琚
,聂开宝,何振亚

电子与信息学报 , 2003,
Abstract: The separability and separating conditions for mixed signals are analyzed in this paper. The limitation of nonlinear blind source separation methods is proposed. A new nonlinear BSS approach is developed by applying Edgeworth expansion and adaptive cumulant estimation into information back propagation algorithm. Computer simulation shows the validity of the proposed algorithm in some ad hoc model. A comparison with the Gram-Charlier expansion method is given.
Overlapping Caused by Fourier Transformation Profilometry Based on Tow-frequency Grating
双频光栅傅里叶变换轮廓术频谱混叠研究

QIAO Nao-sheng,ZHAO Hua-jun,YAO Chun-mei,CAI Xin-hua,PENG Guang-han,
乔闹生
,赵华君,姚春梅,蔡新华,彭光含

光子学报 , 2009,
Abstract: The possibility of frequency overlapping was discussed when the Fourier transformation of deformed fringe for discontinuous object that contain mutation was executed by the method of dual-frequency grating.The condition of separation between f1 of low frequency grating and f2 of high frequency grating was deduced,and frequency overlapping of the same grating because of the nonlinearity of detector was analyzed.For the overlapping between f1 and f2 is the chief condition,computer simulation and experiment on the condition prove that f1 and f2 are overlapped when f2<2f1,f1 and f2 are separated when f2>2f1.
Overlapping Branes in M-Theory  [PDF]
Jerome P. Gauntlett,David A. Kastor,Jennie Traschen
Physics , 1996, DOI: 10.1016/0550-3213(96)00423-3
Abstract: We construct new supersymmetric solutions of $D$=11 supergravity describing $n$ orthogonally ``overlapping" membranes and fivebranes for $n$=2,\dots,8. Overlapping branes arise after separating intersecting branes in a direction transverse to all of the branes. The solutions, which generalize known intersecting brane solutions, preserve at least $2^{-n}$ of the supersymmetry. Each pairwise overlap involves a membrane overlapping a membrane in a 0-brane, a fivebrane overlapping a fivebrane in a 3-brane or a membrane overlapping a fivebrane in a string. After reducing $n$ overlapping membranes to obtain $n$ overlapping $D$-2-branes in $D$=10, $T$-duality generates new overlapping $D$-brane solutions in type IIA and type IIB string theory. Uplifting certain type IIA solutions leads to the $D$=11 solutions. Some of the new solutions reduce to dilaton black holes in $D$=4. Additionally, we present a $D$=10 solution that describes two $D$-5-branes overlapping in a string. $T$-duality then generates further $D$=10 solutions and uplifting one of the type IIA solutions gives a new $D$=11 solution describing two fivebranes overlapping in a string.
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