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32×32元硅盖革APD探测器的凝视型激光3维成像 被引量:1
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作者 王江 王鸥 +5 位作者 陈蔚 袁利 柯尊贵 郝昕 孔繁林 姜鹏 《激光技术》 北大核心 2025年第3期463-468,共6页
为了实现对特定目标区域的高精度探测,采用了凝视型激光3维成像技术,基于自研32×32元硅盖革模式激光焦平面探测器,搭建了一套1064 nm激光3维成像实验系统。探测器组件采用带有温度采样与控制模块的斯特林制冷型封装技术,实现了在... 为了实现对特定目标区域的高精度探测,采用了凝视型激光3维成像技术,基于自研32×32元硅盖革模式激光焦平面探测器,搭建了一套1064 nm激光3维成像实验系统。探测器组件采用带有温度采样与控制模块的斯特林制冷型封装技术,实现了在深低温环境下的高控温精度、高稳定性运行;成像系统通过发射脉冲激光点阵照射目标区域,并利用上述探测器捕获激光回波信号;经距离门噪声过滤和3维点云数据预处理后,取得了200 m处目标的3维距离图像以及670 m处目标的2维强度图像。结果表明,该激光3维成像系统具有30 cm的距离分辨率,可精确展现目标的几何细节。该研究为硅盖革模式激光焦平面探测器凝视3维成像技术的实际工程应用提供了参考。 展开更多
关键词 传感器技术 凝视型激光3维成像 雪崩光电二极管 盖革模式
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基于点云配准的LiDAR输电线路绝缘子3维重建
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作者 张正鹏 刘建华 +2 位作者 胡天硕 刘树辉 谢欣余 《激光技术》 北大核心 2025年第5期675-682,共8页
为了解决由于绝缘子点云结构稀疏、类型和挂点难于识别,导致建模困难的问题,实现绝缘子的高精度重建与挂接,采用了一种整合分类、配准以及挂点优化的绝缘子3维重建方法。利用绝缘子组的空间可分性和类型间姿态差异性,采用聚类和拟合方... 为了解决由于绝缘子点云结构稀疏、类型和挂点难于识别,导致建模困难的问题,实现绝缘子的高精度重建与挂接,采用了一种整合分类、配准以及挂点优化的绝缘子3维重建方法。利用绝缘子组的空间可分性和类型间姿态差异性,采用聚类和拟合方法实现对输电杆塔中多类型绝缘子分类,解决了现有方法只能区分单一类型的问题;针对稀疏和含有噪声的绝缘子点云配准和重建困难的问题,提出了一种从粗到精的针对低质量绝缘子点云配准和优化的重建方法;采用寻找最近邻挂点的方法,解决绝缘子与杆塔挂接不准确的问题,并对不同类型的绝缘子点云进行了实验。结果表明,绝缘子的重建精度可达到0.3000m以内,能准确还原实际的形状和空间姿态。该研究为绝缘子重建的工程化应用提供了参考。 展开更多
关键词 图像处理 绝缘子3维重建 点云配准 姿态提取 模型组合优化 数字孪生
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Near-field 3D imaging approach combining MJSR and FGG-NUFFT 被引量:3
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作者 WANG Shuzhen FANG Yang +2 位作者 ZHANG Jin’gang LUO Mingshi LI Qing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1096-1109,共14页
A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of t... A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of the compressed sensing(CS)theory and the matched filtering(MF)technique.The approach has the advantages of high precision and high efficiency:multichannel joint sparse constraint is adopted to improve the problem that the images recovered by the single channel imaging algorithms do not necessarily share the same positions of the scattering centers;the CS dictionary is constructed by combining MF and FGG-NUFFT,so as to improve the imaging efficiency and memory requirement.Firstly,a near-field 3 D imaging model of joint sparse recovery is constructed by combining the MF-based imaging method.Secondly,FGG-NUFFT and reverse FGG-NUFFT are used to replace the interpolation and Fourier transform in MF-based imaging methods,and a sensing matrix with high precision and high efficiency is constructed according to the traditional imaging process.Thirdly,a fast imaging recovery is performed by using the improved separable surrogate functionals(SSF)optimization algorithm,only with matrix and vector multiplication.Finally,a 3 D imagery of the near-field target is obtained by using both the horizontal and the pitching interferometric phase information.This paper contains two imaging models,the only difference is the sub-aperture method used in inverse synthetic aperture radar(ISAR)imaging.Compared to traditional CS-based imaging methods,the proposed method includes both forward transform and inverse transform in each iteration,which improves the quality of reconstruction.The experimental results show that,the proposed method improves the imaging accuracy by about O(10),accelerates the imaging speed by five times and reduces the memory usage by about O(10~2). 展开更多
关键词 interference imaging joint sparse recovery compressed sensing(CS) matching filtering(MF) fast Gaussian gridding nonuniform fast Fourier transform(NUFFT) near-field 3d imaging
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Monopulse instantaneous 3D imaging for wideband radar system 被引量:3
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作者 LI Yuhan QI Wei +2 位作者 DENG Zhenmiao FU Maozhong ZHANG Yunjian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期53-67,共15页
To avoid the complicated motion compensation in interferometric inverse synthetic aperture(InISAR)and achieve realtime three-dimensional(3 D)imaging,a novel approach for 3 D imaging of the target only using a single e... To avoid the complicated motion compensation in interferometric inverse synthetic aperture(InISAR)and achieve realtime three-dimensional(3 D)imaging,a novel approach for 3 D imaging of the target only using a single echo is presented.This method is based on an isolated scatterer model assumption,thus the scatterers in the beam can be extracted individually.The radial range of each scatterer is estimated by the maximal likelihood estimation.Then,the horizontal and vertical wave path difference is derived by using the phase comparison technology for each scatterer,respectively.Finally,by utilizing the relationship among the 3 D coordinates,the radial range,the horizontal and vertical wave path difference,the 3 D image of the target can be reconstructed.The reconstructed image is free from the limitation in InISAR that the image plane depends on the target's own motions and on its relative position with respect to the radar.Furthermore,a phase ambiguity resolution method is adopted to ensure the success of the 3 D imaging when phase ambiguity occurs.It can be noted that the proposed phase ambiguity resolution method only uses one antenna pair and does not require a priori knowledge,whereas the existing phase ambiguity methods may require two or more antenna pairs or a priori knowledge for phase unwarping.To evaluate the performance of the proposed method,the theoretical analyses on estimation accuracy are presented and the simulations in various scenarios are also carried out. 展开更多
关键词 cross-correlation operation phase ambiguity resolution wave path difference estimation monopulse three-dimensional(3d)imaging
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Airborne sparse flight array SAR 3D imaging based on compressed sensing in frequency domain 被引量:2
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作者 TIAN He DONG Chunzhu +1 位作者 YIN Hongcheng YUAN Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期56-67,共12页
In airborne array synthetic aperture radar(SAR), the three-dimensional(3D) imaging performance and cross-track resolution depends on the length of the equivalent array. In this paper, Barker sequence criterion is used... In airborne array synthetic aperture radar(SAR), the three-dimensional(3D) imaging performance and cross-track resolution depends on the length of the equivalent array. In this paper, Barker sequence criterion is used for sparse flight sampling of airborne array SAR, in order to obtain high cross-track resolution in as few times of flights as possible. Under each flight, the imaging algorithm of back projection(BP) and the data extraction method based on modified uniformly redundant arrays(MURAs) are utilized to obtain complex 3D image pairs. To solve the side-lobe noise in images, the interferometry between each image pair is implemented, and compressed sensing(CS) reconstruction is adopted in the frequency domain. Furthermore, to restore the geometrical relationship between each flight, the phase information corresponding to negative MURA is compensated on each single-pass image reconstructed by CS. Finally,by coherent accumulation of each complex image, the high resolution in cross-track direction is obtained. Simulations and experiments in X-band verify the availability. 展开更多
关键词 three-dimensional(3d)imaging synthetic aperture radar(SAR) sparse flight INTERFEROMETRY compressed sensing(CS)
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3D Confocal Raman Imaging of Oil-Rich Emulsion from Enzyme-Assisted Aqueous Extraction of Extruded Soybean Powder
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作者 Wu Longkun Wang Limin +5 位作者 Qi Baokun Zhang Xiaonan Chen Fusheng Li Yang Sui Xiaonan Jiang Lianzhou 《大豆科技》 2019年第S01期76-83,96,共9页
The understanding of the structure morphology of oil-rich emulsion from enzyme-assisted extraction processing(EAEP)was a critical step to break the oil-rich emulsion structure in order to recover oil.Albeit EAEP metho... The understanding of the structure morphology of oil-rich emulsion from enzyme-assisted extraction processing(EAEP)was a critical step to break the oil-rich emulsion structure in order to recover oil.Albeit EAEP method has been applied as an alternative way to conventional solvent extraction method,the structure morphology of oil-rich emulsion was still unclear.The current study aimed to investigate the structure morphology of oil-rich emulsion from EAEP using 3 D confocal Raman imaging technique.With increasing the enzymatic hydrolysis duration from 1 to 3 h,the stability of oil-rich emulsion was decreased as visualized in the 3 D confocal Raman images that the protein and oil were mixed together.The subsequent Raman spectrum analysis further revealed that the decreased stability of oil-rich emulsion was due to the protein aggregations via SS bonds or protein-lipid interactions.The conformational transfer in protein indicated the formation of a compact structure. 展开更多
关键词 Enzyme-assisted extraction process Oil-rich emulsion 3d confocal Raman imaging technique Raman spectrum analysis
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基于波场外推的3D VSP波动方程深度偏移成像方法研究——以胜利垦71-检41井为例 被引量:3
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作者 姚忠瑞 《山东科技大学学报(自然科学版)》 CAS 2007年第4期31-35,共5页
针对3D VSP成像方法中的保幅性差、对复杂构造的归位不准、分辨率低等问题,提出基于波场外推的波动方程深度偏移成像方法。该方法以三维声波方程为出发点,对有限差分法进行误差补偿,多方面确保成像的稳定性,并充分考虑到波场在地下传播... 针对3D VSP成像方法中的保幅性差、对复杂构造的归位不准、分辨率低等问题,提出基于波场外推的波动方程深度偏移成像方法。该方法以三维声波方程为出发点,对有限差分法进行误差补偿,多方面确保成像的稳定性,并充分考虑到波场在地下传播过程中的绕射和折射效应,避免了Kirchhoff方法中的高频近似假设和在复杂构造区的焦散及多路径现象。实现过程是将三维VSP数据按井中检波器的位置抽成共检波点道集,对共波点道集进行三维叠前深度偏移,对偏移后的数据进行同深度叠加。该成像方法在胜利垦71井区3D VSP实际资料处理中取得了比较好的成像效果。实际处理结果证明:该方法正确、可行、实用。 展开更多
关键词 3d vsp 波场延拓 波动方程 偏移成像
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基于角度域共成像点道集的3D VSP速度分析方法研究 被引量:2
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作者 孔庆丰 《石油物探》 EI CSCD 北大核心 2014年第2期157-163,172,共8页
获得高精度的3DVSP偏移速度场是3DVSP资料井周构造高精度成像的关键问题和难点之一。目前,基于角度域共成像点道集(Angle Domain Common Image Gathers,ADCIGs)的速度分析方法已经成为地面三维地震资料叠前深度偏移中速度模型建立的有... 获得高精度的3DVSP偏移速度场是3DVSP资料井周构造高精度成像的关键问题和难点之一。目前,基于角度域共成像点道集(Angle Domain Common Image Gathers,ADCIGs)的速度分析方法已经成为地面三维地震资料叠前深度偏移中速度模型建立的有效工具。借鉴地面地震资料基于ADCIGs的速度分析方法,开展了基于ADCIGs的3DVSP资料叠前深度偏移速度分析方法研究。首先给定一个初始速度场进行偏移,形成ADCIGs;接着通过剩余曲率计算获得估计速度与真实速度之比的速度谱函数;最后根据速度谱进行速度迭代更新和3DVSP资料偏移成像。模型数据和实际资料试算结果表明,该方法可以较好地改善3DVSP资料成像精度,提高3DVSP资料描述井周细微构造的能力。 展开更多
关键词 3d vsp 偏移速度场 角度域共成像点道集 剩余曲率计算 速度谱分析
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3D VSP资料AVA分析预处理方法
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作者 乔玉雷 《山东科技大学学报(自然科学版)》 CAS 2010年第1期5-8,共4页
3D VSP数据与地面地震数据相比接收噪音少、反射角信息比较丰富,更能直接反映波的运动学和动力学特征,因此,利用3D VSP AVO/AVA分析推测地层岩性和含油气性,为隐蔽性油气藏勘探提供有效技术手段。但是,用于AVA分析的VSP资料必须进行严... 3D VSP数据与地面地震数据相比接收噪音少、反射角信息比较丰富,更能直接反映波的运动学和动力学特征,因此,利用3D VSP AVO/AVA分析推测地层岩性和含油气性,为隐蔽性油气藏勘探提供有效技术手段。但是,用于AVA分析的VSP资料必须进行严格的振幅保持、地表一致性和角道集提取等精细预处理。本文采用全波场振幅补偿、两步法统计子波反褶积和直射线路径近似角度道集转换等适于3D VSP资料特点的精细预处理方法,最大程度地消除影响振幅的各种主要非地质因素,确保从角道集上得到的AVA响应是地下真实的AVA反映,取得了很好的处理效果。 展开更多
关键词 3d vsp AVA 振幅补偿 角道集 反褶积
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Stereo particle image velocimetry measurement of 3D soil deformation around laterally loaded pile in sand 被引量:6
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作者 袁炳祥 谌文武 +2 位作者 姜彤 汪亦显 陈科平 《Journal of Central South University》 SCIE EI CAS 2013年第3期791-798,共8页
A developed stereo particle image velocimetry(stereo-PIV) system was proposed to measure three-dimensional(3D) soil deformation around a laterally loaded pile in sand.The stereo-PIV technique extended 2D measurement t... A developed stereo particle image velocimetry(stereo-PIV) system was proposed to measure three-dimensional(3D) soil deformation around a laterally loaded pile in sand.The stereo-PIV technique extended 2D measurement to 3D based on a binocular vision model,where two cameras with a well geometrical setting were utilized to image the same object simultaneously.This system utilized two open software packages and some simple programs in MATLAB,which can easily be adjusted to meet user needs at a low cost.The failure planes form an angle with the horizontal line,which are measured at 27°-29°,approximately three-fourths of the frictional angle of soil.The edge of the strain wedge formed in front of the pile is an arc,which is slightly different from the straight line reported in the literature.The active and passive influence zones are about twice and six times of the diameter of the pile,respectively.The test demonstrates the good performance and feasibility of this stereo-PIV system for more advanced geotechnical testing. 展开更多
关键词 particle image velocimetry digital image correlation stereo particle image velocimetry laterally loaded pile scaledmodel 3d soil deformation soil-structural interaction
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Multi-focus image fusion based on block matching in 3D transform domain 被引量:5
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作者 YANG Dongsheng HU Shaohai +2 位作者 LIU Shuaiqi MA Xiaole SUN Yuchao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期415-428,共14页
Fusion methods based on multi-scale transforms have become the mainstream of the pixel-level image fusion. However,most of these methods cannot fully exploit spatial domain information of source images, which lead to ... Fusion methods based on multi-scale transforms have become the mainstream of the pixel-level image fusion. However,most of these methods cannot fully exploit spatial domain information of source images, which lead to the degradation of image.This paper presents a fusion framework based on block-matching and 3D(BM3D) multi-scale transform. The algorithm first divides the image into different blocks and groups these 2D image blocks into 3D arrays by their similarity. Then it uses a 3D transform which consists of a 2D multi-scale and a 1D transform to transfer the arrays into transform coefficients, and then the obtained low-and high-coefficients are fused by different fusion rules. The final fused image is obtained from a series of fused 3D image block groups after the inverse transform by using an aggregation process. In the experimental part, we comparatively analyze some existing algorithms and the using of different transforms, e.g. non-subsampled Contourlet transform(NSCT), non-subsampled Shearlet transform(NSST), in the 3D transform step. Experimental results show that the proposed fusion framework can not only improve subjective visual effect, but also obtain better objective evaluation criteria than state-of-the-art methods. 展开更多
关键词 image fusion block matching 3d transform block-matching and 3d(BM3d) non-subsampled Shearlet transform(NSST)
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3D VSP技术在辽河东部凹陷二次开发中的应用 被引量:3
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作者 王艳华 孙岩 +3 位作者 朴永红 王光明 陈沅忠 张晓璐 《石油地球物理勘探》 EI CSCD 北大核心 2018年第A02期83-89,10,共8页
在油田进入储层描述和开发、二次开发阶段,地面地震已不能满足储层精细描述、储层参数求取及高分辨率地震勘探的要求。为此,结合3D VSP的技术特点,确定了综合解释工作流程。首先利用准确的零井源距VSP时—深关系标定各种资料(测井、钻... 在油田进入储层描述和开发、二次开发阶段,地面地震已不能满足储层精细描述、储层参数求取及高分辨率地震勘探的要求。为此,结合3D VSP的技术特点,确定了综合解释工作流程。首先利用准确的零井源距VSP时—深关系标定各种资料(测井、钻井、三维地面地震、3D VSP等)、确定储层参数,利用零井源距VSP资料筛选对储层敏感的属性。其次,利用3D VSP资料进行储层精细解释,识别研究区低幅度构造及小断层;通过波阻抗反演和属性分析等技术预测砂体展布及剩余油气分布。最后,结合前期分析结果综合评价储层,指出有利油气分布区,为开发评价部署提供依据。结果表明,研究区在经过一次开发后剩余油整体呈零散分布的状态,在构造高部位含油气性较差,剩余油主要分布在北东部斜坡的高部位。 展开更多
关键词 3d vsp 二次开发 地震波形反演 属性分析 剩余油预测
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3D surface profile diagnosis using digital image processing for laboratory use 被引量:2
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作者 Robert FRISCHER Ondrej KREJCAR +1 位作者 Ali SELAMAT Kamil KUCA 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第3期811-823,共13页
The measurement of the surface quality and the profile preciseness is major issues in many industrial branches such that the surface quality of semi products directly affects the subsequent production steps.Although,t... The measurement of the surface quality and the profile preciseness is major issues in many industrial branches such that the surface quality of semi products directly affects the subsequent production steps.Although,there are many ways to obtain required data,the hardware necessary for the measurements such as 2D or 3D scanners,depending on the problem’s complexity,is too expensive.Therefore,in this paper,what we put forward as a novelty is an algorithm which is verified on the model of simple 3D scanner on the image processing basis with the resolution of 0.1 mm.There are many ways to scan surface profile;however,the image processing currently is the most trending topic in industry automation.Most importantly,in order to obtain surface images,standard high resolution reflex camera is used and thus the post processing could be realized with MatLab as the software environment.Therefore,this solution is an alternative to the expensive scanners,and single-purpose devices could be extended by many additional functions. 展开更多
关键词 profile diagnostics image processing 3d surface MatLab measurement
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A modified OMP method for multi-orbit three dimensional ISAR imaging of the space target 被引量:2
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作者 JIANG Libing ZHENG Shuyu +2 位作者 YANG Qingwei YANG Peng WANG Zhuang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期879-893,共15页
The conventional two dimensional(2D)inverse synthetic aperture radar(ISAR)imaging fails to provide the targets'three dimensional(3D)information.In this paper,a 3D ISAR imaging method for the space target is propos... The conventional two dimensional(2D)inverse synthetic aperture radar(ISAR)imaging fails to provide the targets'three dimensional(3D)information.In this paper,a 3D ISAR imaging method for the space target is proposed based on mutliorbit observation data and an improved orthogonal matching pursuit(OMP)algorithm.Firstly,the 3D scattered field data is converted into a set of 2D matrix by stacking slices of the 3D data along the elevation direction dimension.Then,an improved OMP algorithm is applied to recover the space target's amplitude information via the 2D matrix data.Finally,scattering centers can be reconstructed with specific three dimensional locations.Numerical simulations are provided to demonstrate the effectiveness and superiority of the proposed 3D imaging method. 展开更多
关键词 three dimensional inverse synthetic aperture radar(3d ISAR)imaging space target improved orthogonal matching pursuit(OMP)algorithm scattering centers
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SAR tomography imaging via higher-order spectrum analysis 被引量:2
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作者 Wang Jinfeng Pi Yiming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期748-754,共7页
To deal with the non-Caussian noise in standard 2-D SAR images, the deramped signal in imaging plane, and the possible symmetric distribution of complex noise, the fourth-order cumulant of complex process is introduce... To deal with the non-Caussian noise in standard 2-D SAR images, the deramped signal in imaging plane, and the possible symmetric distribution of complex noise, the fourth-order cumulant of complex process is introduced into SAR tomography. With the estimated AR parameters of ARMA model of noise through Yule-Walker equation, the signal series of height is pre-filtered. Then, through ESPRIT, the spectrum is obtained and the aperture in height direction is synthesized. Finally, the SAR tomography imaging of scene is achieved. The results of processing on signal with non-Gaussian noise demonstrate the robustness of the proposed method. The tomography imaging of the scenes shows that the higher-order spectrum analysis is feasible in the application. 展开更多
关键词 synthetic aperture radar 3-d imaging TOMOGRAPHY high-order spectrum analysis nongaussian
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Assembly of a highly stable luminescent Zn5 cluster and application to bio-imaging
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作者 Ze-hui LIU Jin HUANG +1 位作者 Ming-hua ZENG Zheng YIN 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2017年第10期1022-1022,共1页
OBJECTIVE To explore a novel pH-sensitive fluorescent probe for in vivo tumor imaging.METHODS Zn5 were obtained in 140℃ after mixed with Me OH,water,Zn(NO_3)2·6 H_2O,H4L and trimethylamine.The fluorescence spect... OBJECTIVE To explore a novel pH-sensitive fluorescent probe for in vivo tumor imaging.METHODS Zn5 were obtained in 140℃ after mixed with Me OH,water,Zn(NO_3)2·6 H_2O,H4L and trimethylamine.The fluorescence spectra of Zn5 with the same concentration in different pH aqueous solutions were detected.And the stability of Zn5 was investigated by time dependent fluorescence emission spectra of Zn5 in BSA aqueous solution and 5.0% serum solution.Then,the cytotoxicity of Zn5 was detected by MTT assays.To clarify whether a similar fluorescence response occurs in biological organisms,He La cells were pretreated with probe Zn5(0.5 μmol·L^(-1)) and fluorescence imaging were collected for targeting lysosomes in living cells because of lysosomes′ acidic microenvironment.The A375 tumor-bearing mice were used to assess the imaging ability of Zn5 in vivo.Mouse tumor xenografts were established by injection of A375 cells with 2×10~6 cells per flank.Probe(1 μg·g^(-1)) was administered to mice by injection.Images were obtained using IVIS Spectrum CT Imaging System.RESULTS There is a 11-fold intensity increasing as the pH values changing from 8 to 2.The almost unchanged emission intensities suggest Zn5 is stable in both BSA and serum.Zn5 has negligible cytotoxicity for He La,293 T and CHO-K1 cells.Zn5 can selectively display lysosomes in living cells.Both the 2D and 3D images in vivo distinguish the tumor from other tissues with good fluorescence contrast.CONCLUSION The high chemical stability,emission in the Vis/NIR range,pH sensitivity,a pKa located in the tumor pH range,and low toxicity make Zn5 is suitable for application as a pH-sensitive fluorescent probe for bio-imaging. 展开更多
关键词 3d metal coordination cluster bio imaging fluorescence probes pH sensitivity Zn clusters
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多光谱图像的3D EBCOT压缩编码算法 被引量:6
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作者 肖江 吴成柯 +2 位作者 李云松 相里斌 杨建峰 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2005年第4期549-554,共6页
提出了一种新的多光谱图像压缩方案,三维率失真优化截取码块编码(3DEBCOT)算法根据多光谱图像的成像特点,利用非对称的三维离散小波变换去除多光谱图像的空间冗余和频域的相关性,再通过拓展改进最新的静止图像压缩标准JPEG2000中的二维... 提出了一种新的多光谱图像压缩方案,三维率失真优化截取码块编码(3DEBCOT)算法根据多光谱图像的成像特点,利用非对称的三维离散小波变换去除多光谱图像的空间冗余和频域的相关性,再通过拓展改进最新的静止图像压缩标准JPEG2000中的二维率失真优化截取内嵌码块编码(2DEBCOT)算法,在比特平面编码器中引入谱间上下文,使用相应算术编码器并对经过三维小波变换后的系数进行编码,提高了多光谱图像的压缩效率.根据具体要求组织的内嵌码流,可继承获得JPEG2000标准内嵌码流抗误码等优良特性.使用该方法对一组6波段多光谱图像压缩编码后的重建图像显示,具有比三维小波分层树集合分割排序编码的算法(3DSPIHT)具有更好的图像质量和压缩性能. 展开更多
关键词 多光谱图像 图像压缩 内嵌编码 JPEG2000 三维离散小波变换
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基于3-D图像的植物亏水胁迫萎蔫体态辨识方法 被引量:8
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作者 张慧娟 赵燕东 +3 位作者 孙宇瑞 王聪颖 蔡祥 Schulze Lammers P 《农业机械学报》 EI CAS CSCD 北大核心 2011年第1期154-158,共5页
萎蔫现象是植物亏水胁迫环境下表现出的一种生命特征。为了定量辨识植株的萎蔫体态,在应用激光扫描装置快速获取植株3-D图像基础上,定义了4种萎蔫指数,即叶面卷曲统计指数、叶片形心的高斯曲率、基于形心切平面的叶尖投影以及叶片边缘... 萎蔫现象是植物亏水胁迫环境下表现出的一种生命特征。为了定量辨识植株的萎蔫体态,在应用激光扫描装置快速获取植株3-D图像基础上,定义了4种萎蔫指数,即叶面卷曲统计指数、叶片形心的高斯曲率、基于形心切平面的叶尖投影以及叶片边缘投影求和平均。实验方法将叶片萎蔫程度分为5个等级水平(LS1~LS5),通过逐一检验每种定义的萎蔫指数是否具有单调性得出可应用性结论。实验结果表明距离投影算法满足萎蔫指数的单调要求,尤其是叶片边缘投影求和平均萎蔫指数具有更好的鲁棒性。 展开更多
关键词 亏水胁迫 萎蔫指数 三维图像 形态辨识
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一种新的3-D小波变换图像编码方法 被引量:9
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作者 张文忠 沈兰荪 《电子学报》 EI CAS CSCD 北大核心 1997年第10期32-36,共5页
基于图像序列三维小波变换的视频编码技术是一种很有潜力的编码方法.本文针对目前实际中采用的三维小波变换只是一种准三维变换,不能提供对变换结果的统一描述等不足,推导了信号真正的三维小波变换的有关理论及其实现方法.在此基础... 基于图像序列三维小波变换的视频编码技术是一种很有潜力的编码方法.本文针对目前实际中采用的三维小波变换只是一种准三维变换,不能提供对变换结果的统一描述等不足,推导了信号真正的三维小波变换的有关理论及其实现方法.在此基础上,我们将这种三维小波变换方法用于视频图像的编码,模拟结果表明这种编码结构具有良好性能,值得进一步的深入研究. 展开更多
关键词 视频图像编码 3-d小波变换 多分辨率分析
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基于PC机的断层图象序列3-D表面重建 被引量:3
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作者 罗斌 汪炳权 《电子科学学刊》 CSCD 1993年第1期75-78,共4页
由断层图象序列重建三维物体模型及其可见表面显示是目前国际上十分活跃的研究课题。本文对X射线CT图象序列重建三维对象模型,以及可见表面3-D显示进行了研究。提出一种给定分段点数的轮廓多边形近似方法,继而提出一种快速断面图象间轮... 由断层图象序列重建三维物体模型及其可见表面显示是目前国际上十分活跃的研究课题。本文对X射线CT图象序列重建三维对象模型,以及可见表面3-D显示进行了研究。提出一种给定分段点数的轮廓多边形近似方法,继而提出一种快速断面图象间轮廊插值方法。对重建出的人体肝脏体元阵列,用深度和梯度明暗显示方法进行显示,肝脏可见表面的3-D显示结果令人满意。全部软件都是在以PC/AT为主机,配以PC-VISION图象处理板的微机图象处理系统上,用C语言编程实现的。 展开更多
关键词 断层图象 三维显示 微机 三维物体
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