联合多特征提取与内部优化的海陆分离

目前大多数海陆分离方法依靠先验信息或仅利用灰度特征对图像进行处理,对导致的误分割或大量孤立区域无法较好处理,造成后续处理工作难度大。针对这一问题,提出一种联合多特征提取与分离结果优化的海陆分离方法。针对不同的陆地类型提取不同的特征进行分割,对得到的结果采用面积与纹理相结合的方式进行优化,进而得到最终的海陆分离结果。实验结果表明,本文方法与常用的海陆分离方法相比能够快速完整地实现海陆分离并将陆地屏蔽,有利于后续处理工作的进行。     

基于混合模型的SAR影像海陆分割算法

合成孔径雷达(SAR)影像的海陆分割是诸如海洋目 标检测和识别等基于海洋区域SAR影像解译的基础和关键环节之一。为解决复杂背景下遥感 影像海陆分割问题,提出一种基于混合概率模型的海陆分割算 法。首先利用Harris角点检测算法检测出影像中包含角点 的图像子块,进而通过均值漂移(MS,mean-shift)算法对图像子块进行聚类分析得到陆地 区域的 像素样本;然后利用陆地的像素样本,通过最大期望(EM,expectation maximization)迭代 算法拟合出混合模型概率 密度分布的相关参数;最后通过混合概率模型检测出陆地前景区域,得到 海陆分割结果。实验证明,本文方法能够对包含海陆的异质遥感影像实现有效的海陆分割。     

面向海上目标的海陆分离方法研究

随着信息技术的发展,越来越多的国家将关注焦点放在海洋上。快速有效地将海洋与陆地分离对实现海上目标解译、目标检测、识别与提取以及场景理解等具有重要的作用。首先介绍了海陆分离的重要意义和主要内容,在总结各海陆分离方法的基础上将其分为基于先验信息的海陆分离和基于图像特征差异的海陆分离两大类;然后对各方法进行了系统的综述并进行对比分析,指出存在的一些问题;最后给出了总结和展望。     

基于大脑层状皮质模型的立体图像质量评价

针对利用相机传感器模式噪声的篡改检测在待测 图像纹理复杂区域存在较高的虚警,提出了一种考 虑纹理复杂度的自适应阈值检测算法。根据Nyman-Pierson(N-P)准则,确定不同纹理复杂 度对应的相关性匹配 判定阈值,而得到相关性阈值与纹理复杂度的关系拟合函数。在不重叠分块计算待测 图像噪声残差 和其来源相机传感器模式噪声对应块相关性的基础之上,根据待测图像块不同的纹理复杂度 进行相关性匹 配,确定大致篡改位置;再用快速零均值归一化互相关(ZNCC) 算法计算两噪声图像中大致篡改区域对应点的相关性,实现精确定 位。在手机图像库上的实验表明,与现有的固定阈值方法相比,本文算法的检测率达 到了98.8%,而虚 警率仅为1.897%,有效地降低纹理复杂区域的虚警率,并实现对篡改 区域的精确定位;同 时,与传统的滑动窗口方法相比,本文算法检测效率平均提高了26倍 。     

基于多特征动态融合模型的海陆分割算法

海陆分割是遥感图像中进行海上目标检测、监视的关键技术.传统的基于灰度的海陆分割算法没有充分利用图像中的梯度、纹理等灰度变化及空间分布信息;而基于梯度或纹理的海陆分割算法又没有考虑到图像本身灰度特性.由此提出基于多特征动态融合模型的海陆分割算法,该算法通过动态融合模型提取多种图像特征,生成综合特征图,并对综合特征图进行分...     

基于逻辑校准的多分类残差网络的肺分割算法

针对图像噪声以及血管、支气管等因素引起的肺分割困难的问题,提出了一种基于逻辑校准的多分类残差网络分割算法.该算法将图像区域划分为肺、背景及边界三类,通过扩大不同类型间的差异来提升分割准确率.算法先将图像分割为固定尺寸区域,然后利用残差网络提取纹理特征进行分类训练与测试,实现粗分割.最后对边界区域阈值处理实现细分割.利用公开数据集对该算法进行了测试,实验结果表明,此分割算法在召回率、精确率以及交并比等方面均优于当下前沿的分割网络之一的U-Net,分别达到99.79％,98.13％和97.83％,可为后续的肺部疾病临床诊断提供参考依据.     

基于多尺度图像融合信息的沥青路面三维成像方法

基于图像处理的沥青路面纹理三维重建技术具有快速、全面、分辨率高等优点，针对沥青路面颜色集中、特征点不明显导致三维纹理检测精度低的问题，提出一种基于多尺度图像融合的双目视觉技术。通过加权最小二乘滤波实现图像多尺度分解，利用跨尺度聚合模型融合多尺度图像信息进行沥青路面三维重建，提高了双目重建的精度。通过区域纹理参数，将所提方法与激光扫描仪进行了比较。结果表明，所提方法的区域纹理参数结果与激光扫描仪的结果比较接近。     

基于区域特征合并的分水岭图像分割

传统分水岭变换图像分割方法容易造成过度分割,不利于后期的图像分析与处理。采用一种分水岭变换结合区域特征合并的方法,首先将原始图像进行形态学变换,获取梯度图像;再进行分水岭变换,并将运算后的结果进行基于区域纹理、灰度一致性及区域平滑性等特征的区域合并;最终获取分割结果。实验结果表明,与传统分水岭变换方法相比,该方法能够有效降低因噪声、明暗纹理产生的过分割现象,方法可行、有效。     

基于图像特征的铁路车辆制动组件异常检测

铁路车辆制动组件图像目标与背景无法分离,导致组件异常检测结果不精准,提出基于图像特征的铁路车辆制动组件异常检测方法。使用TFDS系统采集车辆制动组件图像,构建图像区域阶段矩阵和中心矩阵,使用二值化处理方法预处理图像。构建图像特征模型,将RGB空间转换为HSV空间,根据颜色感知度对图像进行非均匀量化处理,利用欧氏距离分析图像帧间差异。利用K-means统计理论,将不同位置特征与背景属性值转换为距离矩阵,通过计算被聚类对象和其感知范围内所有对象整体相似性,结合异常序列实现制动组件异常检测。由实验结果可知,该方法能够清晰识别制动缸体压强异常情况,经过7 min保压后检测的压强为127 kPa,与实际压强一致,检测结果精准。     

针对间断纹理环境中的图像特征追踪和匹配算法研究

针对同时定位与地图构建(SLAM)中的特征匹配关键环节,提出一种融合特征点和特征区域的图像追踪与匹配算法,以解决交替出现纹理丰富和纹理缺失的间断纹理环境中图像特征易丢失、误匹配率较高的问题。首先,利用ORB算法和半稠密直接法分别对图像提取特征点和特征区域。其次,使用渐进一致采样法(PROSAC)剔除ORB算法的误匹配特征点,并计算特征点的正确匹配率。最后,针对纹理缺失环境中特征点丢失严重的问题,以特征点的正确匹配率作为判断依据,对低匹配率图像,则基于特征区域使用半稠密直接法实现图像的追踪,同时对追踪结果进行非线性优化,提高了特征区域追踪的准确性和稳定性。实验结果表明,该算法适用于间断纹理环境,在纹理丰富和纹理缺失条件下均可提高图像匹配的准确率。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.