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Principle of Coordinates Acquisition Based on Single Camera 被引量:5
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作者 黄桂平 叶声华 《Transactions of Tianjin University》 EI CAS 2005年第1期49-52,共4页
The principle and accuracy of 3-D coordinates acquisition using one single camera and the Aided Measuring Probe(AMP) are discussed in this paper. Using one single camera and one AMP which has several embedded targets ... The principle and accuracy of 3-D coordinates acquisition using one single camera and the Aided Measuring Probe(AMP) are discussed in this paper. Using one single camera and one AMP which has several embedded targets and one tip with known coordinates, the single camera′s orientation and location can be calculated. After orientation, the global coordinate system is obtained. During measurement, the camera is fixed firstly, then the AMP is held and the feature point is touched.The camera is triggered lastly. The position and orientation of the AMP are therefore calculated from the size and position of its image on the sensor. Since the tip point of AMP has known relation with the embedded targets, the feature point can be measured. Tests show that the accuracy of length measurement is 0.2 mm and accuracy for flatness measurement in XSY-plane is 0.1 mm. 展开更多
关键词 3-d coordinates acquisition single camera collinear equation spatial resection aided measuring probe
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Visualization of 3-D temperature distribution in a 300 MW twin-furnace coal-fired boiler 被引量:4
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作者 YANG Chao ZHOU Huai-chun HUANG Zhi-feng 《Journal of China University of Mining and Technology》 EI 2008年第1期33-37,共5页
Until now, it has been difficult to obtain on-line three-dimensional (3-D) temperature distribution information which can reflect the overall combustion condition in the furnace of a coal-fired power plant boiler. A c... Until now, it has been difficult to obtain on-line three-dimensional (3-D) temperature distribution information which can reflect the overall combustion condition in the furnace of a coal-fired power plant boiler. A combustion monitoring system is introduced which can solve the problem efficiently. Through this system, the 3-D temperature distribution in a coal-fired boiler furnace can be obtained using a novel flame image processing technique. Briefly, we first outline the visualization principle. Then, the hardware and software design of the system in a 300 MW twin-furnace coal-fired boiler are introduced in detail. The visualization of the 3-D temperature distribution in the twin-furnace boiler is realized with an industrial computer and the Distributed Control System (DCS) of the boiler. The practical operation of the system shows that it can provide valuable combustion information of a furnace and is useful for the combustion diagnosis and adjustment in coal-fired power plants. 展开更多
关键词 thermal power engineering combustion monitoring system 3-d temperature distribution CCD camera flame imageprocessing technique
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Characteristics of a Terrain-Following Sigma Coordinate 被引量:1
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作者 LI Yi-Yuan WANG Bin WANG Dong-Hai 《Atmospheric and Oceanic Science Letters》 2011年第3期157-161,共5页
This study quantifies the main characteristics of a terrain-following, G-coordinate through mathematical analyses of its covariant and contravariant basis vectors as well as the vertical coordinate of σ. A 3-D schema... This study quantifies the main characteristics of a terrain-following, G-coordinate through mathematical analyses of its covariant and contravariant basis vectors as well as the vertical coordinate of σ. A 3-D schematic of the σ-coordinate in a curvilinear coordinate system is provided in this study. The characteristics of the basis vectors were broken down into their "local vector charac- teristics" and "spatial distribution characteristics", and the exact expressions of the covariant; in addition, the con- travariant basis vectors of the G-coordinate used to eluci- date their detailed characteristics were properly solved. Through rewriting the expression of the vertical coordi- nate of G, a mathematical expression of all the cr-coor- dinate surfaces was found, thereby quantifying the so- called terrain-following characteristics and lack of flexi- bility to adjust the slope variation of G-coordinate sur- faces for the classic definition of G. Finally, an analysis on the range value of the vertical coordinate demonstrated that the general value range of G could be obtained by eliminating the G-coordinate surfaces below the Earth's surface. All these quantitative descriptions of the charac- teristics of G-coordinate were the foundation for improv- ing the G-coordinate or creating a new one. 展开更多
关键词 quantitative description sigma coordinate 3-d schematic basis vectors non-orthogonal
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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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300MW锅炉燃烧三维温度场可视化监测系统设计及运行分析 被引量:13
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作者 吴吕斌 罗自学 +1 位作者 杨超 周怀春 《中国电力》 CSCD 北大核心 2004年第10期62-65,共4页
基于对燃烧火焰图像本质的分析,在沙角A电厂5号机上进行了三维可视化监测系统的硬、软件设计,得到了炉内实时三维温度场和总辐射能信号,通过与热工信号的相关性分析,提出采用炉膛总辐射能参与协调控制的思想。
关键词 300MW锅炉 三维温度场 辐射能信号 燃烧火焰 热工 运行分析 协调控制 可视化监测 实时 系统设计
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A New Cadmium(Ш) Polymer Based on 3,5-Pyrazoledicarboxylic Acid:Hydrothermal Synthesis and Crystal Structure 被引量:2
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作者 周秋香 王猛 白晓杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第1期7-10,共4页
The reaction of CdCl3.2.5H2O with 3,5-pyrazoledicaiboxylic acid under hydrother-mal conditions produce a novel three-dimensional(3-D) coordination polymer [Cd2(C5H2O4N2)2.2H2O]n.The title compound crystallizes in ... The reaction of CdCl3.2.5H2O with 3,5-pyrazoledicaiboxylic acid under hydrother-mal conditions produce a novel three-dimensional(3-D) coordination polymer [Cd2(C5H2O4N2)2.2H2O]n.The title compound crystallizes in the monoclinic system,space group P21/c with a = 6.422(4),b = 12.334(7),c = 8.936(6) ,β = 104.793(7)°,V = 684.4(7) 3,Z = 4,Dc = 2.761 g/cm3,μ = 3.181 mm-1,F(000) = 544,R = 0.0248 and wR = 0.0624.In the crystal structure of the title compround,molecules are linked through N-H...O hydrogen bonds,forming chains running along the a axis.Every Cd(Ш) coordinates with four molecules of ligand and one water molecule,forming a pentagomal-bipyramidal geometry. 展开更多
关键词 hydrothermal reaction 3-d coordination polymer crystal structure
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Squint-mode InISAR imaging based on nonlinear least square and coordinates transform 被引量:5
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作者 LIU ChengLan HE Feng +2 位作者 GAO XunZhang LI Xiang SHEN RongJun 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第12期3332-3340,共9页
Aiming at the interferometric inverse synthetic aperture radar (InlSAR) imaging in the presence of squint, we investigate the influence of squint on the InlSAR imaging. First, coupling of the squint additive phase a... Aiming at the interferometric inverse synthetic aperture radar (InlSAR) imaging in the presence of squint, we investigate the influence of squint on the InlSAR imaging. First, coupling of the squint additive phase and the target azimuth/altitude coordinates to be solved may make the solution more difficult. Second, the squint angle may lead to estimation error of the vertical coordinates and distortion of the ultimate image. Traditional InlSAR imaging algorithms can not solve the above two problems effectively, so we propose a new method which combines the nonlinear least square (NLS) and coordinates transform (CT) to estimate the target coordinates, and a three-dimensional (3-D) image consistent with the real target is obtained accordingly. Simulations show that the proposed method is effective for the squint-mode InlSAR imaging. 展开更多
关键词 interferometric inverse synthetic aperture radar (InlSAR) three dimensional 3-d imaging squint mode nonlinear least square (NLS) coordinates transform (CT)
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THREE—DIMENSIONAL GAS TURBINE COMBUSTOR PERFORMANCE MODELING 被引量:3
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作者 ZhaoJianxing ZhouFenglun LeiYubing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第1期65-70,共6页
Numerical analysis of three-dimensional(3-D)two-phase reacting flowfield in an annular combustor wity the dump diffuser is developed in arbitrary curvilinear coordi-nates.Combustor performances are estimated by the em... Numerical analysis of three-dimensional(3-D)two-phase reacting flowfield in an annular combustor wity the dump diffuser is developed in arbitrary curvilinear coordi-nates.Combustor performances are estimated by the em-pirical-analytical desing method.Ths influence of three inlet velocity profiles of the prediffuser and two operating conditions on combustor preformance and flow character-istic is predicted. 展开更多
关键词 COMBUSTOR performance numerical calcula-tion annular COMBUSTOR DUMP DIFFUSER 3-d body-fitted coordinate 环形燃烧室 数值计算 扩压器 燃烧室性能
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Numerical and Dimensional Analysis for Prediction of Line Heating Residual Deformations 被引量:1
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作者 Pankaj Biswas Nisith Ranjan Mandal Om Prakash Sha 《Journal of Marine Science and Application》 2010年第1期14-21,共8页
Line heating process is a very complex phenomenon as a variety of factors affects the amount of residual deformations. Numerical thermal and mechanical analysis of line heating for prediction of residual deformation i... Line heating process is a very complex phenomenon as a variety of factors affects the amount of residual deformations. Numerical thermal and mechanical analysis of line heating for prediction of residual deformation is time consuming. In the present work dimensional analysis has been presented to obtain a new relationship between input parameters and resulting residual deformations during line heating process. The temperature distribution and residual deformations for 6 mm, 8 mm, 10 mm and 12 mm thick steel plates were numerically estimated and compared with experimental and published results. Extensive data generated through a validated FE model were used to find co-relationship between the input parameters and the resulting residual deformation by multiple regression analysis. The results obtained from the deformation equations developed in this work compared well with those of the FE analysis with a drop in the computation time in the order of 100 (computational time required for FE analysis is around 7 200 second to 9 000 seconds and where the time required for getting the residual deformation by developed equations is only 60 to 90 seconds). 展开更多
关键词 dimensional analysis 3-d finite element analysis elasto-plastic analysis residual deformations multiple regression analysis oxy-acetylene gas flame
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Three-dimensional cooperative guidance laws against stationary and maneuvering targets 被引量:38
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作者 Zhao Jiang Zhou Rui Dong Zhuoning 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第4期1104-1120,共17页
This paper presents the cooperative strategies for salvo attack of multiple missiles based on the classical proportional navigation(PN) algorithm.The three-dimensional(3-D) guidance laws are developed in a quite s... This paper presents the cooperative strategies for salvo attack of multiple missiles based on the classical proportional navigation(PN) algorithm.The three-dimensional(3-D) guidance laws are developed in a quite simple formulation that consists of a PN component for target capture and a coordination component for simultaneous arrival.The centralized algorithms come into effect when the global information of time-to-go estimation is obtained, whereas the decentralized algorithms have better performance when each missile can only collect information from neighbors.Numerical simulations demonstrate that the proposed coordination algorithms are feasible to perform the cooperative engagement of multiple missiles against both stationary and maneuvering targets.The effectiveness of the 3-D guidance laws is also discussed. 展开更多
关键词 coordination algorithms Maneuvering target Missile guidance Multiple missiles Three-dimensional 3-d
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一种运用绝对编码器和单片机的行车定位系统设计 被引量:1
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作者 黄益锦 万舟 孙斌 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第S2期205-207,211,共4页
针对行车在运行过程中,位置难以准确定位的问题,设计了一种行车定位系统.该系统运用绝对编码器对行车各项运行和移动数据实现精确采集,并利用单片机和采集的数据建立了行车的三维空间坐标,实现对行车的定位,并通过显示屏实时显示.
关键词 行车定位 绝对编码器 单片机 三维坐标
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