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An Experimental System Development for Head Posture Estimation Based on 3-D Images Measurement
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作者 Chen Xu Cunwei Lu 《Journal of Computer and Communications》 2014年第2期57-63,共7页
Although automobile is an indispensable vehicle to modern life, it also serves as a social problem with a big traffic accident. Among the reasons of traffic accidents, careless driving accounts for the largest part. S... Although automobile is an indispensable vehicle to modern life, it also serves as a social problem with a big traffic accident. Among the reasons of traffic accidents, careless driving accounts for the largest part. So in order to avoid the careless driving, a system which can measure the posture of a driver and warns driver to drive carefully in the case of looking aside is necessary. Although the image measurement method is used broadly, there is a problem on which measurement accuracy is influenced by environment light, makeup of the driver, etc. in the general method based on the two-dimensional image. Therefore, in this study, we propose an image measurement method to obtain the head posture of driver. First we use three-dimensional measurement method which based on the infrared pattern projection to get 3-D information of head, and then we calculate the angle for faces. In this paper, we explain the composition method of an experiment system, and the results of head posture measurement experiment. 展开更多
关键词 Careless Driving 3-d image measurement INFRARED Pattern PROJECTION Head POSTURE ESTIMATION
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Adaptive Window Based 3-D Feature Selection for Multispectral Image Classification Using Firefly Algorithm
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作者 M.Rajakani R.J.Kavitha A.Ramachandran 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期265-280,共16页
Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafte... Feature extraction is the most critical step in classification of multispectral image.The classification accuracy is mainly influenced by the feature sets that are selected to classify the image.In the past,handcrafted feature sets are used which are not adaptive for different image domains.To overcome this,an evolu-tionary learning method is developed to automatically learn the spatial-spectral features for classification.A modified Firefly Algorithm(FA)which achieves maximum classification accuracy with reduced size of feature set is proposed to gain the interest of feature selection for this purpose.For extracting the most effi-cient features from the data set,we have used 3-D discrete wavelet transform which decompose the multispectral image in all three dimensions.For selecting spatial and spectral features we have studied three different approaches namely overlapping window(OW-3DFS),non-overlapping window(NW-3DFS)adaptive window cube(AW-3DFS)and Pixel based technique.Fivefold Multiclass Support Vector Machine(MSVM)is used for classification purpose.Experiments con-ducted on Madurai LISS IV multispectral image exploited that the adaptive win-dow approach is used to increase the classification accuracy. 展开更多
关键词 Multispectral image modifiedfirefly algorithm 3-d feature extraction feature selection multiclass support vector machine CLASSIFICATION
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MODELING OF 3-D IMAGES AND SPACE MARKOV CUBIC MESH MODELS
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作者 钱唯 《Journal of Electronics(China)》 1990年第3期280-284,共5页
Three-dimensional(3-D)Markov cubic random mesh models are presented andproved in the form of two theorems in details.Its applications to the modeling and description of3-D images are described.The model presented here... Three-dimensional(3-D)Markov cubic random mesh models are presented andproved in the form of two theorems in details.Its applications to the modeling and description of3-D images are described.The model presented here is a appropriate mathematical tool for thesegmentation,modeling,classification and other processing.Finally,an example is given. 展开更多
关键词 MARKOV CUBIC MESH model Modeling 3-d image
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3D Depth Measurement for Holoscopic 3D Imaging System
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作者 Eman Alazawi Mohammad Rafiq Swash Maysam Abbod 《Journal of Computer and Communications》 2016年第6期49-67,共19页
Holoscopic 3D imaging is a true 3D imaging system mimics fly’s eye technique to acquire a true 3D optical model of a real scene. To reconstruct the 3D image computationally, an efficient implementation of an Auto-Fea... Holoscopic 3D imaging is a true 3D imaging system mimics fly’s eye technique to acquire a true 3D optical model of a real scene. To reconstruct the 3D image computationally, an efficient implementation of an Auto-Feature-Edge (AFE) descriptor algorithm is required that provides an individual feature detector for integration of 3D information to locate objects in the scene. The AFE descriptor plays a key role in simplifying the detection of both edge-based and region-based objects. The detector is based on a Multi-Quantize Adaptive Local Histogram Analysis (MQALHA) algorithm. This is distinctive for each Feature-Edge (FE) block i.e. the large contrast changes (gradients) in FE are easier to localise. The novelty of this work lies in generating a free-noise 3D-Map (3DM) according to a correlation analysis of region contours. This automatically combines the exploitation of the available depth estimation technique with edge-based feature shape recognition technique. The application area consists of two varied domains, which prove the efficiency and robustness of the approach: a) extracting a set of setting feature-edges, for both tracking and mapping process for 3D depthmap estimation, and b) separation and recognition of focus objects in the scene. Experimental results show that the proposed 3DM technique is performed efficiently compared to the state-of-the-art algorithms. 展开更多
关键词 Holoscopic 3D image Edge Detection Auto-Thresholding Depthmap Integral image Local Histogram Analysis Object Recognition and Depth measurement
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C_(2/3)经关节突经椎弓根螺钉固定的影像学测量及可行性分析
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作者 陈钧麟 马向阳 +6 位作者 邹小宝 付索超 朱昌荣 邓琛府 马仁财 陈泽星 夏虹 《中国临床解剖学杂志》 CSCD 北大核心 2024年第2期126-130,139,共6页
目的测量C_(2/3)经关节突经椎弓根螺钉相关影像学指标,并分析该置钉技术的可行性。方法收集120例全颈椎CT薄层扫描数据,其中男性75例,女性45例。设定C_(2/3)经关节突经椎弓根螺钉的进钉点,即进钉点在枢椎侧块的水平中线与中外1/3垂线交... 目的测量C_(2/3)经关节突经椎弓根螺钉相关影像学指标,并分析该置钉技术的可行性。方法收集120例全颈椎CT薄层扫描数据,其中男性75例,女性45例。设定C_(2/3)经关节突经椎弓根螺钉的进钉点,即进钉点在枢椎侧块的水平中线与中外1/3垂线交点处,螺钉自枢椎侧块穿C_(2/3)关节突关节、C_(3)侧块止于C_(3)椎弓根下缘。测量C_(2/3)经关节突经椎弓根螺钉相关影像学数据,包括C_(3)椎弓根宽度与高度,螺钉通道长度,内倾角度,头倾角度,最狭窄处宽度。并分析各项测量结果之间的关系。结果C_(3)椎弓根平均宽度5.48 mm,平均高度6.82 mm,螺钉通道平均长度18.68 mm,平均内倾角度20.46°,平均头倾角度50.1°,最狭窄处平均宽度2.80 mm。C_(3)椎弓根宽度与高度呈正相关(P=0.000),螺钉通道长度与C_(3)椎弓根宽度、高度呈正相关(P=0.000;P=0.000),螺钉通道最狭窄处宽度与C_(3)椎弓根宽度、高度呈正相关(P=0.000;P=0.000)。240例置钉测量数据中,如使用3.5 mm直径螺钉,均可完成置钉,C_(2/3)经关节突经椎弓根螺钉适用于所有患者。结论C_(2/3)经关节突经椎弓根螺钉在解剖学上是可行的,可作为上颈椎后路钉棒内固定补充的置钉技术。 展开更多
关键词 枢椎 影像学测量 C_(2/3)经关节突经椎弓根螺钉
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Sparse flight spotlight mode 3-D imaging of spaceborne SAR based on sparse spectrum and principal component analysis 被引量:1
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作者 ZHOU Kai LI Daojing +7 位作者 CUI Anjing HAN Dong TIAN He YU Haifeng DU Jianbo LIU Lei ZHU Yu ZHANG Running 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第5期1143-1151,共9页
The spaceborne synthetic aperture radar(SAR)sparse flight 3-D imaging technology through multiple observations of the cross-track direction is designed to form the cross-track equivalent aperture,and achieve the third... The spaceborne synthetic aperture radar(SAR)sparse flight 3-D imaging technology through multiple observations of the cross-track direction is designed to form the cross-track equivalent aperture,and achieve the third dimensionality recognition.In this paper,combined with the actual triple star orbits,a sparse flight spaceborne SAR 3-D imaging method based on the sparse spectrum of interferometry and the principal component analysis(PCA)is presented.Firstly,interferometric processing is utilized to reach an effective sparse representation of radar images in the frequency domain.Secondly,as a method with simple principle and fast calculation,the PCA is introduced to extract the main features of the image spectrum according to its principal characteristics.Finally,the 3-D image can be obtained by inverse transformation of the reconstructed spectrum by the PCA.The simulation results of 4.84 km equivalent cross-track aperture and corresponding 1.78 m cross-track resolution verify the effective suppression of this method on high-frequency sidelobe noise introduced by sparse flight with a sparsity of 49%and random noise introduced by the receiver.Meanwhile,due to the influence of orbit distribution of the actual triple star orbits,the simulation results of the sparse flight with the 7-bit Barker code orbits are given as a comparison and reference to illuminate the significance of orbit distribution for this reconstruction results.This method has prospects for sparse flight 3-D imaging in high latitude areas for its short revisit period. 展开更多
关键词 principal component analysis(PCA) spaceborne synthetic aperture radar(SAR) sparse flight sparse spectrum by interferometry 3-d imaging
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A"messenger zone hypothesis"based on the visual three-dimensional spatial distribution of motoneurons innervating deep limb muscles
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作者 Chen Huang Shen Wang +3 位作者 Jin Deng Xinyi Gu Shuhang Guo Xiaofeng Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1559-1567,共9页
Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneuro... Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneurons innervating differe nt muscles is limited.In this study,we investigated the spatial distribution and relative position of different motoneurons that control the deep muscles of the mouse hindlimbs,which were innervated by the obturator nerve,femoral nerve,inferior gluteal nerve,deep pe roneal nerve,and tibial nerve.Locations were visualized by combining a multiplex retrograde tracking technique compatible with three-dimensional imaging of solvent-cleared o rgans(3DISCO)and 3-D imaging technology based on lightsheet fluorescence microscopy(LSFM).Additionally,we propose the hypothesis that"messenger zones"exist as interlaced areas between the motoneuron pools that dominate the synergistic or antagonist muscle groups.We hypothesize that these interlaced neurons may participate in muscle coordination as messenger neurons.Analysis revealed the precise mutual positional relationships among the many motoneurons that innervate different deep muscles of the mouse.Not only do these findings update and supplement our knowledge regarding the overall spatial layout of spinal motoneurons that control mouse limb muscles,but they also provide insights into the mechanisms through which muscle activity is coordinated and the architecture of motor circuits. 展开更多
关键词 3-d imaging MOTONEURONS multiple retrograde tracing muscle coordination skeletal muscle spatial distribution optical tissue clearing
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Comparison of Laboratory Measurements for IR Imaging System Performance
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作者 李升才 徐宗昌 肖顺旺 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第2期187-190,共4页
Sensitivity and human performance are two important parameters for IR imaging system. Noise equivalent temperature difference (NETD) and minimum resolvable temperature difference (MRTD) can describe sensitivity and hu... Sensitivity and human performance are two important parameters for IR imaging system. Noise equivalent temperature difference (NETD) and minimum resolvable temperature difference (MRTD) can describe sensitivity and human performance of IR imaging system. So a lot of engineers apply themselves to studying the methods to measure NETD and MRTD for IR imaging system. The classical laboratory measurement methodologies for NETD and MRTD are introduced. And, two new approaches to three-dimensional (3-D) noise and MRTD/MRC are also portrayed, which can overcome some of the disadvantages existed in classical testing of NETD and MRTD. With the help of the new laboratory measurements, the disadvantages of the classical methods to measure NETD and MRTD can be solved. 展开更多
关键词 NETD MRTD MTF IR imagING system 3-d noise
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Linear Phase FIR Filter on Measuring 3-D Surface
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作者 WANG Yunshan,YANG Fujun,LI Wei (Shandong University of Technology,Jinan 250061,CHN) 《Semiconductor Photonics and Technology》 CAS 1997年第2期29-34,共6页
LinearPhaseFIRFilteronMeasuring3-DSurface①WANGYunshan,YANGFujun,LIWei(ShandongUniversityofTechnology,Jinan25... LinearPhaseFIRFilteronMeasuring3-DSurface①WANGYunshan,YANGFujun,LIWei(ShandongUniversityofTechnology,Jinan250061,CHN)Abstract... 展开更多
关键词 Linear-Phase FIR FILTER Profilometry Projected GRATING image 3-d SURFACE
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Precise 3D shape measurement of three-dimensional digital image correlation for complex surfaces 被引量:3
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作者 YAN TianHao SU Yong ZHANG QingChuan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第1期68-73,共6页
Three dimensional-digital image correlation(3 D-DIC) is a widely used optical metrology in the experimental mechanics community because of its reliability, practicality, and flexibility. Although the precision of digi... Three dimensional-digital image correlation(3 D-DIC) is a widely used optical metrology in the experimental mechanics community because of its reliability, practicality, and flexibility. Although the precision of digital image correlation(DIC) has been thoroughly studied theoretically and numerically, verification experiments have seldom been performed, especially for complex surfaces with a small field of view(FOV). In this work, the shape of a 1-yuan coin was measured using 3 D-DIC; the shape was complex due to the presence of many fine details, and the FOV was relatively small because the coin diameter was only 25 mm. During the experiment, a novel strategy for speckle production was developed: white paint was simply sprayed onto the surface. Black paint was not used; instead, taking advantage of the reflective nature of the coin surface, polarized light and a Polaroid filter were introduced, and the polarization direction was carefully adjusted, ensuring that the spray pattern was extremely thin and that high-quality speckle images with significant contrast were captured. The three-dimensional coin shape was also successfully determined for comparison using a stylus profiler. The results demonstrate that 3 D-DIC provides high precision in shape measurement even for complex surfaces with small FOV. The precision of 3 D-DIC can reach 1/7000 of the field of view, corresponding to about 6 μm in this experiment. 展开更多
关键词 three-dimensional digital image correlation(3D-dIC) measurement precision complex surfaces small field of view polarized light polaroid filter
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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 TENSOR ANALYSIS METHOD FOR ESTIMATING 3-D MOTION PARAMETERS
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作者 李象霖 陈小平 《Journal of Electronics(China)》 1992年第3期209-217,共9页
By using the center projection image sequence to estimate 3-D motion parameters,one needs to know the corresponding relationship between the feature of motion object in spaceand the projection coordinate on image plan... By using the center projection image sequence to estimate 3-D motion parameters,one needs to know the corresponding relationship between the feature of motion object in spaceand the projection coordinate on image plane.In order to avoid using the relationship of featurecorrespondence,the tensor analysis method in the affine transformation system is presented,andthe simulation data of experimental results are given. 展开更多
关键词 SIGNAL processing image SEQUENCE ANALYSIS 3-d motion ANALYSIS TENSOR ANALYSIS method
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Cosmetic Lifting Effect of a Formula Combining Tetrahydroxypropyl Ethylenediamine, Ononis Spinosa and Glycerin as Shown by a New 2-D Imaging Method
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作者 Romain Roure Marion Lanctin +3 位作者 Alex Nkengne Virginie Nollent Liliane Dayan Christiane Bertin 《Journal of Cosmetics, Dermatological Sciences and Applications》 2013年第3期209-215,共7页
Facial sagging is a major aging change that affects the overall shape of the face. Sagging can negatively impact self-perception and consequently quality of life. In order to fight against this aging sign, we develope... Facial sagging is a major aging change that affects the overall shape of the face. Sagging can negatively impact self-perception and consequently quality of life. In order to fight against this aging sign, we developed a combination of three active ingredients: Tetrahydroxypropyl Ethylenediamine (THPE), Ononis Spinosa extract and Glycerin. In a clinical study, we assessed the efficacy of this association on facial sagging and wrinkles, with a special focus on immediate and lasting effects. Thirty-nine women applied the tested product daily during an eight-week treatment period. Clinical grading by experts and a new, easy to operate, 2-D imaging method were performed at different time points. The 2-D imaging method measured the upper eyelid lifting effect. The results showed an immediate and significant improvement in sagging and wrinkle parameters;these benefits were still observed seven hours after the first application. Results also showed a significant long-term improvement. The lifting effect calculated from the 2-D pictures was 1.08 mm immediately after application;the same method showed a 1.80 mm lifting effect following the eight-week treatment period. These results suggest that a skin care product combining THPE, Ononis Spinosa and Glycerin properties may be used to reduce sagging as well as wrinkles with both immediate and long term benefits. 展开更多
关键词 Facial SAGGING WRINKLES Tetrahydroxypropyl ETHYLENEDIAMINE Immediate EFFECT Long-Lasting EFFECT 2-d imaging Lift measurement
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High-accuracy 3-D deformation measurement method with an improved structured-light principle
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作者 GUO QinFeng WANG JinJun 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第12期3450-3461,共12页
In this paper,a high-accuracy 3-D deformation measurement(HADM)method with structured light is proposed and applied to wing deformation measurement in wind tunnel experiments.The present method employs an arbitrarily ... In this paper,a high-accuracy 3-D deformation measurement(HADM)method with structured light is proposed and applied to wing deformation measurement in wind tunnel experiments.The present method employs an arbitrarily arranged fringe projector and a perpendicularly placed camera.The exact phase-height mapping using the phase differences of the projected sinusoidal fringe patterns,as well as the spatial distribution of the fringe,is accurately derived.It not only presents high feasibility but also reduces systemic uncertainties arising from deviations between the ideal model and the real-world conditions.Meanwhile,a dynamic boundary process algorithm is proposed to reduce the measurement uncertainty caused by fringe fracture near the object boundary.It is calibrated that a high accuracy with the average measurement uncertainty of 0.0237 mm is achieved,which is less than 0.01%of the side length of 25 cm of the field of view.In the wind tunnel experiments,the 3-D deformations of the elastic wing,particularly the key geometric parameters such as wing tip position,angle of attack,and dihedral angle,are well reconstructed to provide an in-depth explanation for the aerodynamic characteristics. 展开更多
关键词 3-d deformation measurement wing deformation high accuracy structured light wind tunnel tests
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基于靶标的三目视觉3维坐标测量系统 被引量:2
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作者 张绍兵 熊显名 +2 位作者 蒋曲博 张文涛 胡放荣 《激光技术》 CAS CSCD 北大核心 2013年第4期523-528,共6页
为了解决复杂环境中大视场、高精度、非接触3维测量问题,采用三目摄像机结构,通过靶标成像来测量被测点3维坐标的测量系统。测量时摄像机采集测量靶标的图像,计算机通过图像处理的方法获取测量靶标上标志点的3维坐标,并提出基于被测点... 为了解决复杂环境中大视场、高精度、非接触3维测量问题,采用三目摄像机结构,通过靶标成像来测量被测点3维坐标的测量系统。测量时摄像机采集测量靶标的图像,计算机通过图像处理的方法获取测量靶标上标志点的3维坐标,并提出基于被测点与标志点间距离方程与直线约束的被测点求解优化方法。测量系统通过高精度光栅位移平台带动测量靶标移动来完成测试。结果表明,测量系统在视场范围、测量精度、使用灵活性等方面有较大的改进,能够测量视场深度从2m~5m范围内的视场,测量精度优于0.2mm。 展开更多
关键词 测量与计量 图像处理 3维坐标测量 三目视觉 测量靶标
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国人第3~7肋影像解剖学测量及其临床意义 被引量:2
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作者 何哲 乔贵宾 欧阳钧 《中国临床解剖学杂志》 CSCD 北大核心 2015年第1期33-36,共4页
目的 观测国人第3~7肋形态学参数,为改进常用固定器械、提高肋骨骨折救治水平提供解剖学依据。 方法 随机收集广州军区广州总医院2013~2014年113例行胸部CT扫描患者资料,行胸廓三维重建并对双侧第3-7肋相关参数行影像学测量。 结果... 目的 观测国人第3~7肋形态学参数,为改进常用固定器械、提高肋骨骨折救治水平提供解剖学依据。 方法 随机收集广州军区广州总医院2013~2014年113例行胸部CT扫描患者资料,行胸廓三维重建并对双侧第3-7肋相关参数行影像学测量。 结果 第3~7肋侧区平均宽度(mm)分别为12.79、13.69、14.47、14.79、15.13, 上缘厚度(mm)分别为5.32、5.28、5.46、5.34、5.45,下缘厚度(mm)分别为5.12、5.37、5.38、5.35、5.37, 前扭转角(°)分别为26.69、26.22、25.70、25.16、24.45, 后扭转角(°)分别为10.25、9.87、10.39、9.46、9.30。各参数性别间差异有统计学意义(P<0.05),而各参数年龄差异均无统计学意义(P〉0.05)。 结论 应用CT三维重建可对第3~7肋相关参数行影像学测量,可为设计并研制新型解剖型肋骨固定装置提供解剖学依据。 展开更多
关键词 3—7肋 骨折 影像学测量 解剖型固定
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FY-3气象卫星降水探测能力分析与展望 被引量:9
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作者 谷松岩 卢乃锰 +5 位作者 吴琼 尹红刚 商建 孙逢林 陈林 张鹏 《海洋气象学报》 2022年第2期1-10,共10页
降水是全球能量/水循环中的重要过程。本文着重分析FY-3气象卫星降水探测能力,展望风云卫星后续规划中降水探测技术的发展前景。分析表明,以FY-3降水星为主星,与其他FY-3极轨卫星组成的FY-3气象卫星降水探测体系,在设计层面上,从载荷类... 降水是全球能量/水循环中的重要过程。本文着重分析FY-3气象卫星降水探测能力,展望风云卫星后续规划中降水探测技术的发展前景。分析表明,以FY-3降水星为主星,与其他FY-3极轨卫星组成的FY-3气象卫星降水探测体系,在设计层面上,从载荷类型、数量、通道设置等方面均优于由美国发起并已在轨运行的全球降水测量(Global Precipitation Measurement,GPM)计划核心星的设计性能。FY-3降水星设计装载Ka/Ku双频降水测量雷达,卫星轨道设计覆盖南北纬50°范围内的中低纬地区,对影响我国区域的台风暴雨等强对流天气系统结构具有三维探测能力。FY-3气象卫星星座的降水探测能力为气象防灾减灾提供了基础支撑。 展开更多
关键词 FY-3气象卫星 FY-3降水星 风云降水星座 双频降水测量雷达 微波成像仪
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风云三号(03)批降水测量卫星探测能力及应用 被引量:8
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作者 尹红刚 吴琼 +3 位作者 谷松岩 卢乃锰 商建 窦芳丽 《气象科技进展》 2016年第3期55-61,共7页
风云三号(03)批是我国第二代极轨业务气象卫星的第三个批次,由上午、下午、晨昏和降水测量四颗业务卫星组成。其中,我国首发的降水测量卫星计划装载双频降水测量雷达、微波成像仪、GNSS掩星探测仪和光学成像仪。通过仿真技术,分析风... 风云三号(03)批是我国第二代极轨业务气象卫星的第三个批次,由上午、下午、晨昏和降水测量四颗业务卫星组成。其中,我国首发的降水测量卫星计划装载双频降水测量雷达、微波成像仪、GNSS掩星探测仪和光学成像仪。通过仿真技术,分析风云三号降水测量卫星的功能、性能和设计指标,探讨其降水探测能力。分析表明,风云三号降水测量卫星装载的降水测量雷达从设计层面分析,与美日第二代降水测量卫星GPM搭载的降水雷达DPR性能相当;风云三号降水测量卫星的轨道设计覆盖了南、北纬50°范围内的热带和中纬地区,对影响我国区域的台风系统结构具有三维探测能力;风云三号降水测量卫星上装载的被动微波辐射计相比GPM搭载的微波成像仪增加了50-60和118GHz双氧吸收通道,对陆地弱降水反演等具有应用潜力。总之,风云三号降水测量卫星加上同星配置的其他载荷,整星的降水探测能力优于美日第二代降水测量卫星GPM。 展开更多
关键词 风云三号(03)批 降水测量卫星 降水测量雷达 微波成像仪
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一种高分辨率3维图像的自适应降噪算法 被引量:4
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作者 向志聪 张程潇 +3 位作者 白玉磊 赖文敬 王钦若 周延周 《激光技术》 CAS CSCD 北大核心 2015年第5期697-701,共5页
为了获得高保真3维图像,采用了一种针对高分辨率3维图像的自适应均值降噪算法。首先使用一种由激光器、高分辨率3维相机、直线电机和计算机等设备组成的线激光高精度3维测量实验系统对自然纹理皮革进行测量。然后针对系统测量所得的高... 为了获得高保真3维图像,采用了一种针对高分辨率3维图像的自适应均值降噪算法。首先使用一种由激光器、高分辨率3维相机、直线电机和计算机等设备组成的线激光高精度3维测量实验系统对自然纹理皮革进行测量。然后针对系统测量所得的高分辨率3维自然纹理图像(每英寸点数大于1000),进行了理论分析和实验验证,取得了降噪后的高保真3维图像数据,并与传统的均值滤波、小波变换滤波的降噪效果进行对比。结果表明,该算法能自动选取最优的降噪窗口,有效地去除3维图像的噪声信息,并保留高分辨率图像丰富的边缘、细节信息,最终得到高保真的高分辨率3维自然纹理图像。该实验结果对于高分辨率图像的降噪问题是十分有帮助的。 展开更多
关键词 图像处理 高保真3维图像 自适应均值降噪 高分辨率 线激光 3维测量
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Full 3-D numerical modeling of borehole electric image logging and the evaluation model of fracture 被引量:3
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作者 KE ShiZhen Resource & Information Collage of Chinese Petroleum University,Beijing 102249,China 《Science China Earth Sciences》 SCIE EI CAS 2008年第S2期170-173,共4页
A full 3-D finite element method numerical modeling program is written based on the principle and technical specification of borehole electric image well logging tool. The response of well logging is computed in the f... A full 3-D finite element method numerical modeling program is written based on the principle and technical specification of borehole electric image well logging tool. The response of well logging is computed in the formation media model with a single fracture. The effect of changing fracture aperture and resistivity ratio to the logging response is discussed. The identification ability for two parallel fractures is also present. A quantitative evaluation formula of fracture aperture from borehole electric image logging data is set up. A case study of the model well is done to verify the accuracy of the for-mula. The result indicates that the formula is more accurate than the foreign one. 展开更多
关键词 NUMERICAL modeling BOREHOLE electric image LOGGING 3-d FEM full SCOPE FRACTURE
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