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Parallel computing approach for efficient 3-D X-ray-simulated image reconstruction 被引量:1
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作者 Ou-Yi Li Yang Wang +1 位作者 Qiong Zhang Yong-Hui Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期122-136,共15页
Accurate 3-dimensional(3-D)reconstruction technology for nondestructive testing based on digital radiography(DR)is of great importance for alleviating the drawbacks of the existing computed tomography(CT)-based method... Accurate 3-dimensional(3-D)reconstruction technology for nondestructive testing based on digital radiography(DR)is of great importance for alleviating the drawbacks of the existing computed tomography(CT)-based method.The commonly used Monte Carlo simulation method ensures well-performing imaging results for DR.However,for 3-D reconstruction,it is limited by its high time consumption.To solve this problem,this study proposes a parallel computing method to accelerate Monte Carlo simulation for projection images with a parallel interface and a specific DR application.The images are utilized for 3-D reconstruction of the test model.We verify the accuracy of parallel computing for DR and evaluate the performance of two parallel computing modes-multithreaded applications(G4-MT)and message-passing interfaces(G4-MPI)-by assessing parallel speedup and efficiency.This study explores the scalability of the hybrid G4-MPI and G4-MT modes.The results show that the two parallel computing modes can significantly reduce the Monte Carlo simulation time because the parallel speedup increment of Monte Carlo simulations can be considered linear growth,and the parallel efficiency is maintained at a high level.The hybrid mode has strong scalability,as the overall run time of the 180 simulations using 320 threads is 15.35 h with 10 billion particles emitted,and the parallel speedup can be up to 151.36.The 3-D reconstruction of the model is achieved based on the filtered back projection(FBP)algorithm using 180 projection images obtained with the hybrid G4-MPI and G4-MT.The quality of the reconstructed sliced images is satisfactory because the images can reflect the internal structure of the test model.This method is applied to a complex model,and the quality of the reconstructed images is evaluated. 展开更多
关键词 Parallel computing Monte Carlo Digital radiography 3-d reconstruction
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Using on-site liver 3-D reconstruction and volumetric calculations in split liver transplantation 被引量:3
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作者 Trevor W Reichman Brittany Fiorello +5 位作者 Ian Carmody Humberto Bohorquez Ari Cohen John Seal David Bruce George E Loss 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2016年第6期587-592,共6页
BACKGROUND: Split liver transplantation increases the number of grafts available for transplantation. Pre-recovery assessment of liver graft volume is essential for selecting suitable recipients. The purpose of this ... BACKGROUND: Split liver transplantation increases the number of grafts available for transplantation. Pre-recovery assessment of liver graft volume is essential for selecting suitable recipients. The purpose of this study was to determine the ability and feasibility of constructing a 3-D model to aid in surgical planning and to predict graft weight prior to an in situ division of the donor liver. METHODS: Over 11 months, 3-D volumetric reconstruction of 4 deceased donors was performed using Pathfinder Scout liver volumetric software. Demographic, laboratory, operative, perioperative and survival data for these patients along with donor demographic data were collected prospectively and analyzed retrospectively. RESULTS: The average predicted weight of the grafts from the adult donors obtained from an in situ split procedure were 1130 g (930-1458 g) for the extended right lobe donors and 312 g (222-396 g) for left lateral segment grafts. Actual adult graft weight was 92% of the predicted weight for both the extended right grafts and the left lateral segment grafts. The predicted and actual graft weights for the pediatric donors were 176 g and 210 g for the left lateral segment grafts and 308 g and 280 g for the extended right lobe grafts,respectively. All grafts were transplanted except for the right lobe from the pediatric donors due to the small graft weight.CONCLUSIONS: On-site volumetric assessment of donors provides useful information for the planning of an in situ split and for selection of recipients. This information may expand the donor pool to recipients previously felt to be unsuitable due to donor and/or recipient weight. 展开更多
关键词 split liver transplantation reduced-size liver transplantation 3-d reconstruction
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A 3-D RECONSTRUCTION METHOD BASED ON THE CONSTRAINT OF EPIPOLAR GEOMETRY
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作者 Xu Zhengwei Wu Chengke Pang Chenjing Shen Peiyi(Information Engineering Dept., Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 1998年第3期274-277,共4页
This paper combines the least-square method and iteration method to get the fundamental matrix and develops a new evaluation function based on the epipolar geometry. During the iteration, with the evaluation function ... This paper combines the least-square method and iteration method to get the fundamental matrix and develops a new evaluation function based on the epipolar geometry. During the iteration, with the evaluation function as a measurment, the points which bring larger noise are deleted, and the points with smaller noise are retained, thus the precision of our method is increased. The experiment results indicate the new method is precise in calculation, stable in performance and resistant to noise. 展开更多
关键词 Epipolar GEOMETRY FUNDAMENTAL MATRIX 3-d reconstructION
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Reconstruction of Temperature Field in 3-D, Absorbing, Emitting, and Anisotropically Scattering Medium
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作者 赵敬德 刘妮 钟珂 《Journal of Donghua University(English Edition)》 EI CAS 2006年第2期17-21,共5页
The soft measurement technology of flame temperature field is an efficient method to learn the combustion status in furnace. Generally, it reconstructs the temperature field in furnace through the image of flame, whic... The soft measurement technology of flame temperature field is an efficient method to learn the combustion status in furnace. Generally, it reconstructs the temperature field in furnace through the image of flame, which is a process to solve radiative inverse problem. In this paper, the flame of pulverized coal is considered as 3-D, absorbing, emitting, and anisotropically scattering non-gray medium. Through the study on inverse problem of radiative heat transfer, the temperature field in this kind of medium has been reconstructed. The mechanism of 3-D radiative heat transfer in a rectangular media, which is 2 m×3 m× 5 m and full of CO2, N2 and carbon particles, is studied with Monte Carlo method. The 3-D temperature field in this rectangular space is reconstructed and the influence of particles density profile is discussed. 展开更多
关键词 reconstruction of 3-d temperature field anisotropically scattering non-gray medium Monte Carlo method density profile inverse problem of radiative heat transfer.
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3-D Reconstruction and Visualization of Laser-Scanned Trees by Weighted Locally Optimal Projection and Accurate Modeling Method
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作者 TAMAYO Alexis LI Minglei +1 位作者 LIU Qin ZHANG Meng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第S01期135-142,共8页
This paper presents a method to reconstruct 3-D models of trees from terrestrial laser scan(TLS)point clouds.This method uses the weighted locally optimal projection(WLOP)and the AdTree method to reconstruct detailed ... This paper presents a method to reconstruct 3-D models of trees from terrestrial laser scan(TLS)point clouds.This method uses the weighted locally optimal projection(WLOP)and the AdTree method to reconstruct detailed 3-D tree models.To improve its representation accuracy,the WLOP algorithm is introduced to consolidate the point cloud.Its reconstruction accuracy is tested using a dataset of ten trees,and the one-sided Hausdorff distances between the input point clouds and the resulting 3-D models are measured.The experimental results show that the optimal projection modeling method has an average one-sided Hausdorff distance(mean)lower by 30.74%and 6.43%compared with AdTree and AdQSM methods,respectively.Furthermore,it has an average one-sided Hausdorff distance(RMS)lower by 29.95%and 12.28%compared with AdTree and AdQSM methods.Results show that the 3-D model generated fits closely to the input point cloud data and ensures a high geometrical accuracy. 展开更多
关键词 light detection and ranging(LiDAR) point cloud weighted locally optimal projection(WLOP) 3-d reconstruction AdTree
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RM-CSTV:An effective high-resolution method of non-line-of-sight millimeter-wave radar 3-D imaging 被引量:1
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作者 Xinyuan Liu Shunjun Wei +5 位作者 Wei Pu Xiang Cai Yanbo Wen Shisheng Guo Lingjiang Kong Xiaoling Zhang 《National Science Open》 2024年第5期36-52,共17页
Non-line-of-sight(NLOS)imaging is a novel radar sensing technology that enables the reconstruction of hidden targets.However,it may suffer from synthetic aperture length reduction caused by ambient occlusion.In this s... Non-line-of-sight(NLOS)imaging is a novel radar sensing technology that enables the reconstruction of hidden targets.However,it may suffer from synthetic aperture length reduction caused by ambient occlusion.In this study,a complex total variation(CTV)regularization-based sparse reconstruction method for NLOS three-dimensional(3-D)imaging by millimeter-wave(mm W)radar,named RM-CSTV method,is proposed to improve imaging quality and speed.In this scheme,the NLOS imaging model is first introduced,and associated geometric constraints for NLOS objects are established.Second,an effective high-resolution NLOS imaging method based on the range migration(RM)kernel and complex sparse joint total variation constraint,dubbed as modified RM-CSTV,is proposed for 3-D high-resolution imaging with edge information.The experiments with multi-type NLOS targets show that the proposed RM-CSTV method can provide effective and high-resolution NLOS targets 3-D imaging. 展开更多
关键词 NLOS imaging 3-d-SAR 3-d imaging sparse reconstruction
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Three-Dimensional Interferometric ISAR Sensors Imaging for the Ship Target with Two-Dimensional Sparsity
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作者 Yong Wang Xuefei Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第2期19-31,共13页
There are great challenges for traditional three-dimensional( 3-D) interferometric inverse synthetic aperture radar( In ISAR) imaging algorithms of ship targets w ith 2-D sparsity in actual radar imaging system. To de... There are great challenges for traditional three-dimensional( 3-D) interferometric inverse synthetic aperture radar( In ISAR) imaging algorithms of ship targets w ith 2-D sparsity in actual radar imaging system. To deal w ith this problem,a novel 3-D In ISAR imaging method is proposed in this paper.First,the high-precision gradient adaptive algorithm w as adopted to reconstruct the echoes in range dimension. Then the method of minimizing the entropy of the average range profile w as applied to estimate the parameters w hich are used to compensate translation components of the received echoes. Besides,the phase adjustment and image coregistration of the sparse echoes w ere achieved at the same time through the approach of the joint phase autofocus. Finally,the 3-D geometry coordinates of the ship target w ith 2-D sparsity w ere reconstructed by combining the range measurement and interferometric processing of the ISAR images. Simulation experiments w ere carried out to verify the practicability and effectiveness of the algorithm in the case that the received echoes are in 2-D sparsity. 展开更多
关键词 3-d InISAR 2-d SPARSITY GRADIENT adaptive algorithm AVERAGE range profile joint phase AUTOFOCUS
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PC-BASED SURFACE RECONSTRUCTION OF MEDICAL CT IMAGES
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作者 罗斌 汪炳权 《Journal of Electronics(China)》 1993年第3期284-288,共5页
It is an active research area to reconstruct 3-D object and display its visible surfacesfrom cross-sectional images. In this paper, the methods of reconstructing 3-D object from medicalCT images and displaying the vis... It is an active research area to reconstruct 3-D object and display its visible surfacesfrom cross-sectional images. In this paper, the methods of reconstructing 3-D object from medicalCT images and displaying the visible surfaces are discussed. A polygon approximation methodthat forms polygon with the same number of segment points and a fast interpolation method forcross-sectional contours are presented at first. Then the voxel set of a human liver is reconstructed.And then the liver voxel set is displayed using depth and gradient shading methods. The softwareis written in C programming language at a microcomputer image processing system with a PC/ATcomputer as the host and a PC-VISION board as the image processing unit. The result of theprocessing is satisfying. 展开更多
关键词 3-d reconstruction CROSS-SECTIONAL image COMPUTERIZED TOMOGRAPHY (CT) 3-d display
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A new navigation approach of terrain contour matching based on 3-D terrain reconstruction from onboard image sequence 被引量:5
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作者 LI LiChun1,2,YU QiFeng2,SHANG Yang2,YUAN Yun2,LU HongWei3 & LIU XiaoLin4 1 Beijing Aerospace Control Center,Beijing 100094,China 2 College of Aerospace and Material Engineering,National University of Defense Technology,Changsha 410073,China +1 位作者 3 Equipment Research Institute of PLA’s Second Artillery,Beijing 100085,China 4 College of Mechatronic Engineering and Automation,National University of Defense Technology,Changsha 410073,China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第5期1176-1183,共8页
This article presents a passive navigation method of terrain contour matching by reconstructing the 3-D terrain from the image sequence(acquired by the onboard camera).To achieve automation and simultaneity of the ima... This article presents a passive navigation method of terrain contour matching by reconstructing the 3-D terrain from the image sequence(acquired by the onboard camera).To achieve automation and simultaneity of the image sequence processing for navigation,a correspondence registration method based on control points tracking is proposed which tracks the sparse control points through the whole image sequence and uses them as correspondence in the relation geometry solution.Besides,a key frame selection method based on the images overlapping ratio and intersecting angles is explored,thereafter the requirement for the camera system configuration is provided.The proposed method also includes an optimal local homography estimating algorithm according to the control points,which helps correctly predict points to be matched and their speed corresponding.Consequently,the real-time 3-D terrain of the trajectory thus reconstructed is matched with the referenced terrain map,and the result of which provides navigating information.The digital simulation experiment and the real image based experiment have verified the proposed method. 展开更多
关键词 TERRAIN CONTOUR matching VISION-BASED NAVIGATION 3-d reconstruction control points key frame registration optimal local HOMOGRAPHY
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分形理论在混凝土断裂面研究中的应用 被引量:9
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作者 刘小艳 李文伟 梁正平 《三峡大学学报(自然科学版)》 CAS 2003年第6期495-499,共5页
介绍了对混凝土断裂面进行分形研究的重要性、分形理论及混凝土断裂面分析中几种主要的分数维测量方法;基于激光三角测距原理对试验后的混凝土断裂面进行三维重构.并应用分形几何这一理论工具对重构的断裂面进行分析,得到分数维、粗糙... 介绍了对混凝土断裂面进行分形研究的重要性、分形理论及混凝土断裂面分析中几种主要的分数维测量方法;基于激光三角测距原理对试验后的混凝土断裂面进行三维重构.并应用分形几何这一理论工具对重构的断裂面进行分析,得到分数维、粗糙度等断裂面信息;通过探讨分数维与混凝土的力学性能及材料组成的关系,得出在本文试验条件下分数维与混凝土的抗拉强度、峰值应变及峰值弹模存在反比关系,与水灰比、含气量存在正比关系,与胶凝材料用量存在反比关系等一系列结论. 展开更多
关键词 混凝土 断裂面 分形理论 分数维 粗糙度 三维重构 力学性能
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基于多尺度小波支持向量机的脉冲漏磁缺陷三维轮廓重构 被引量:4
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作者 张韬 左宪章 +1 位作者 田贵云 费骏骉 《数据采集与处理》 CSCD 北大核心 2012年第3期378-384,共7页
针对目前使用的支持向量机(Support vector machine,SVM)核函数在缺陷轮廓重构问题中不能逼近任意目标函数的问题,将小波理论与支持向量机核方法进行结合形成小波支持向量机。同时,根据多分辨率逼近思想引入多尺度小波支持向量机回归模... 针对目前使用的支持向量机(Support vector machine,SVM)核函数在缺陷轮廓重构问题中不能逼近任意目标函数的问题,将小波理论与支持向量机核方法进行结合形成小波支持向量机。同时,根据多分辨率逼近思想引入多尺度小波支持向量机回归模型并将其运用到脉冲漏磁缺陷的三维轮廓重构中。实验中,将缺陷漏磁信号水平分量Bx作为多尺度小波支持向量机网络的输入,缺陷的几何参数长度、宽度、深度作为输出,通过对样本的训练建立了由缺陷的漏磁信号到缺陷三维轮廓图的映射关系,实现了缺陷的三维轮廓重构。实验结果表明该方法具有小波良好的抗噪能力、多尺度逼近方法较高的精度以及SVM很好的泛化能力。 展开更多
关键词 脉冲漏磁 小波 支持向量机 三维轮廓重构
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基于稀疏化LS-SVM的漏磁缺陷三维轮廓重构 被引量:4
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作者 纪凤珠 王长龙 +1 位作者 王瑾 孙钦蕾 《兵工学报》 EI CAS CSCD 北大核心 2008年第5期592-595,共4页
漏磁缺陷轮廓重构是指由检测到的漏磁信号重构缺陷轮廓及参数,是实现漏磁反演的关键。将最小二乘支持向量机(LS-SVM)应用于漏磁缺陷的三维轮廓重构中,并对LS-SVM采取了稀疏化处理,将漏磁信号磁通密度法向分量Bx作为支持向量机网络的输入... 漏磁缺陷轮廓重构是指由检测到的漏磁信号重构缺陷轮廓及参数,是实现漏磁反演的关键。将最小二乘支持向量机(LS-SVM)应用于漏磁缺陷的三维轮廓重构中,并对LS-SVM采取了稀疏化处理,将漏磁信号磁通密度法向分量Bx作为支持向量机网络的输入,缺陷的几何参数长度、宽度、深度作为输出,由实验测量数据和三维有限元仿真计算得到的仿真数据组建样本库。建立了由缺陷的漏磁信号到缺陷三维轮廓图的映射关系,实现了缺陷三维轮廓的重构。实验结果表明:该方法具有很高的精度和很好的泛化能力,同时对噪声也有一定容忍能力。 展开更多
关键词 材料检测与分析技术 漏磁检测 最小二乘支持向量机 稀疏化 三维轮廓重构
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基于光度立体视觉法的织物三维表面形态研究 被引量:4
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作者 杨晓波 《西北纺织工学院学报》 2001年第1期20-25,共6页
提出了一种基于光度立体视觉方法对织物进行三维表面重建 .结合有限差分法 ,获取织物的三维轮廓数据 .
关键词 光度立体视觉法 有限差分 三维表面重建 织物性能
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重温历史经验,进一步改建三门峡水利枢纽,解决潼关以上库区继续淤积和洪涝灾害问题 被引量:4
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作者 曾庆华 《泥沙研究》 CSCD 北大核心 2001年第3期10-15,共6页
本文回顾了三门峡水库兴建和运用中的经验教训 ,回顾了周总理的关怀和决策 ,研究和分析了三门峡水库泥沙淤积给潼关以上库区带来的严重影响。文中指出 :三门峡水利枢纽虽经两次改建 ,潼关以上黄渭洛河汇流区的淤积局面并未得到根本改变... 本文回顾了三门峡水库兴建和运用中的经验教训 ,回顾了周总理的关怀和决策 ,研究和分析了三门峡水库泥沙淤积给潼关以上库区带来的严重影响。文中指出 :三门峡水利枢纽虽经两次改建 ,潼关以上黄渭洛河汇流区的淤积局面并未得到根本改变。潼关河床高程 1996年达 32 8 6m ,比建库前抬高 5 2m ,潼关河床的过水断面现在只有建库前的 1 3左右。由于潼关的“卡口”和侵蚀基面的抬升 ,使渭河、北洛河、小北干流发生严重淤积 ,并且淤积还在向上游延伸。渭河下游建库以来至 1995年共淤积泥沙 12 7亿m3。渭河下游已由地下河变成了地上悬河。本文建议进一步改建三门峡水利枢纽 ,增大泄洪能力 ,降低潼关高程 ,解决潼关以上库区继续淤积和洪涝灾害问题 。 展开更多
关键词 三门峡水库 泥沙淤积 改建工程 潼关河床高程 洪涝灾害
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基于序列剖面图像的透水混凝土三维重建研究 被引量:4
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作者 杨海川 范宏 +1 位作者 苗润阳 谷远春 《混凝土》 CAS 北大核心 2021年第11期146-149,共4页
针对传统的利用CT技术获取的二维图像存在分辨率不足、受噪声和伪影的干扰严重、不能进行精准分割等缺点,提出了一种基于连续二维剖面图像重建透水混凝土三维模型的方法。使用PLC微电脑控制系统精确控制的混凝土自动剖面磨削机对透水混... 针对传统的利用CT技术获取的二维图像存在分辨率不足、受噪声和伪影的干扰严重、不能进行精准分割等缺点,提出了一种基于连续二维剖面图像重建透水混凝土三维模型的方法。使用PLC微电脑控制系统精确控制的混凝土自动剖面磨削机对透水混凝土试块进行分层打磨以获取连续的序列剖面图像,利用三维图像处理软件MIMICS对原始图像进行预处理,采用基于体素的方法建立了3组透水混凝土真实细观结构的三维模型。在此基础上,使用MIMICS软件的虚拟测量功能对孔隙模型的有效孔隙体积进行了统计,同时与浮重法测得的有效孔隙率进行了比较。结果表明,模拟测得的有效孔隙率比浮重法测得的结果偏大,相对误差率为3.48%,进一步证明了本方法的重建模型的准确性。 展开更多
关键词 剖面图像 透水混凝土 图像处理 三维重建
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Crustal structure in Dabieshan UHP metamorphic belt and its tectonic implication 被引量:2
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作者 王椿镛 楼海 王飞 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第5期584-595,共12页
The model of Dabieshan crustal structure has been obtained on the basis of the deep seismic sounding data in thisarea. The 2-D crustal structure shows the feature of the collision orogens and provides some deep geophy... The model of Dabieshan crustal structure has been obtained on the basis of the deep seismic sounding data in thisarea. The 2-D crustal structure shows the feature of the collision orogens and provides some deep geophysicalevidences of the ultra-high pressure (UHP) metamorphic belt. The 3-D upper-crustal velocity struCture reveals thatthe velocity distribution at 2 km deep obviously relates to the surface geological setting and the UHP metarnorphicbelt has the higher velocity at 5~10 km deep. The observed data of Bouguer gravity anomalies reveal a largerrange of negative anomalies in Dabieshan area while the positive anomalies in the UHP metamorphic belt is calculated from the 3-D upper-crustal velocity structure. The 2-D crustal model along the seismic profile shows thatthe 'root' beneath the orogen is only 4-5 km thick and the velocity in the uppermost mantle changes a little in thelateral direction. The inconsistency between the observed and calculated Bouguer gravity anomalies mainly resultsfrom the crust, and at least the middle-upper crust should yield the negative anomalies. The material density of thecrust in the UHP metamorphic belt should be lower than that in the surrounding areas. This material with lowerdensity relates to the collision processes in which Yangtze crust subducted nor'thward to 100 km deep and thenreturned to the crust. 展开更多
关键词 Dabieshan orogen UHP metamorphic belt off-line profile 3-d velocity structure
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基于FTP的三维轮廓测量方法及实验 被引量:1
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作者 江磊 《现代电子技术》 2010年第12期111-113,共3页
为了快速、高精确度地得到物体的三维轮廓信息,在此利用傅里叶变换轮廓术,将被测物体置于光栅投影下,采集变形光栅图像,根据被测物体表面的高度与相位差之间的映射关系,通过在计算机中与参考光栅原像的比较分析,以获得被测物体的三维轮... 为了快速、高精确度地得到物体的三维轮廓信息,在此利用傅里叶变换轮廓术,将被测物体置于光栅投影下,采集变形光栅图像,根据被测物体表面的高度与相位差之间的映射关系,通过在计算机中与参考光栅原像的比较分析,以获得被测物体的三维轮廓信息。实验中搭建了由LCD投影仪、CCD摄像机、图像采集卡和光学导轨等组成的光栅投影测量系统的硬件平台,提出了用1台计算机同时控制投影和采集处理光栅图像,根据映射关系在多次实验中不断修改优化测量参数,做到既不影响视场范围,又保证较高的测量精度,并给出了由计算机重建后较好的三维轮廓图像精度及其实验的测量误差分析。 展开更多
关键词 FTP 三维轮廓测量 光栅投影法 三维重构
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Three-Dimensional Reconstruction of E.coli SecA at Low Resolution
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作者 潘锡江 隋森芳 《Tsinghua Science and Technology》 SCIE EI CAS 2005年第4期445-448,共4页
SecA is the essential component of the signal-peptide dependent translocation pathway in Escherichia coil (E.coh). The structure and function of SecA must be known to understand the molecular mechanism of preprotein... SecA is the essential component of the signal-peptide dependent translocation pathway in Escherichia coil (E.coh). The structure and function of SecA must be known to understand the molecular mechanism of preprotein translocation. The high flexibility of SecA causes a dynamic conformational heterogeneity which presents a barrier to the growth of crystals of high diffraction quality. Electron microscopy was used to resolve the macromolecular structure of SecA in solution by negative staining and single particle analysis at a resolution of 2.9 nm. The structure of E. coil SecA is similar to the dimeric form of Bacillus subtilis SecA and is 10 nm × 10 nm × 5 nm in size. 展开更多
关键词 single-particle analysis electron microscopy SECA 3-d reconstruction
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Virtual Temporal Bone Anatomy
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作者 XIA Yin, LI Xi-ping, HAN De-min, Department of Otorhinolaryngology, Beijing Tongren Hospital, Capital Medical University, Beijing, China, 100730 ZHOU Guo-hong, ZHAO Yuan-yuan Biomedical Academy of Capital Medical University 《Journal of Otology》 2007年第1期56-59,共4页
Background The Visible Human Project(VHP) initiated by the U.S. National Library of Medicine has drawn much attention and interests from around the world. The Visible Chinese Human(VCH) project has started in China. T... Background The Visible Human Project(VHP) initiated by the U.S. National Library of Medicine has drawn much attention and interests from around the world. The Visible Chinese Human(VCH) project has started in China. The current study aims at acquiring a feasible virtual methodology for reconstructing the temporal bone of the Chinese population, which may provide an accurate 3-D model of important temporal bone structures that can be used in teaching and patient care for medical scientists and clinicians. Methods A series of sectional images of the temporal bone were generated from section slices of a female cadaver head. On each sectional image, SOIs (structures of interest) were segmented by carefully defining their contours and filling their areas with certain gray scale values. The processed volume data were then inducted into the 3D Slicer software(developed by the Surgical Planning Lab at Brigham and Women’s Hospital and the MIT AI Lab) for resegmentation and generation of a set of tagged images of the SOIs. 3D surface models of SOIs were then reconstructed from these images. Results The temporal bone and structures in the temporal bone, including the tympanic cavity, mastoid cells, sigmoid sinus and internal carotid artery, were successfully reconstructed. The orientation of and spatial relationship among these structures were easily visualized in the reconstructed surface models. Conclusion The 3D Slicer software can be used for 3- dimensional visualization of anatomic structures in the temporal bone, which will greatly facilitate the advance of knowledge and techniques critical for studying and treating disorders involving the temporal bone. 展开更多
关键词 3-d reconstruction temporal bone Chinese Virtual Human
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Three-dimensional crustal velocity structure model of the middle-eastern north China Craton (HBCrust1.0) 被引量:31
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作者 DUAN YongHong WANG FuYun +6 位作者 ZHANG XianKang LIN JiYan LIU Zhi LIU BaoFeng YANG ZhuoXin GUO WenBin WEI YunHao 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第7期1477-1488,共12页
Lithosphere thinning and destruction in the middle-eastern North China Craton(NCC), a region susceptible to strong earthquakes, is one of the research hotspots in solid earth science. All 42 seismic wide-angle reflect... Lithosphere thinning and destruction in the middle-eastern North China Craton(NCC), a region susceptible to strong earthquakes, is one of the research hotspots in solid earth science. All 42 seismic wide-angle reflection/refraction profiles have been completed in the middle-eastern NCC. We collect all the 2-D profiling results and perform gridding of the velocity and interface depth data, building a 3-D crustal velocity structure model for the middle-eastern NCC, named HBCrust1.0, by using the Kriging interpolation method. Our result shows that the first-arrival times calculated by HBCust1.0 fit well with the observations. The result demonstrates that the upper crust is the main seismogenic layer, and the brittle-ductile transition occurs at depths near interface C(the interface between upper and lower crust). The depth of interface Moho varies beneath the source area of the Tangshan earthquake, and a low-velocity structure is found to extend from the source area to the lower crust. Based on these observations, it can be inferred that stress accumulation responsible for the Tangshan earthquake may have been closely related to the migration and deformation of the mantle materials. Comparisons of the average velocities of the whole crust, the upper and the lower crust show that the average velocity of the lower crust under the central part of the North China Basin(NCB) in the east of the craton is obviously higher than the regional average. This high-velocity probably results from long-term underplating of the mantle magma. 展开更多
关键词 Middle-eastern of the North China Craton DSS profile 3-d P-wave velocity structure Earthquake Craton destruction
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