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Application of 3-D Geoscience Modeling Technology for the Estimation of Solid Mineral Reserves 被引量:15
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作者 PAN Mao LI Jun +1 位作者 WANG Zhangang JIN Jiangjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期655-660,共6页
Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D g... Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D geoscience modeling technology (3-D GMT), this paper discusses the application of 3-D GMT for the estimation of solid mineral reserves, emphatically introducing its workflow and two key technologies, 3-D orebody surface modeling, and property modeling. Moreover, the paper analyzes the limitations of traditional methods, such as the section method and geological block method, and points out the advantages of 3-D GMT: building more accurate 3-D orebody models, expressing the internal inhomogeneous attributes of an orebody, reducing the potential for errors in the estimation of reserves, and implementing dynamic estimations of reserves. 展开更多
关键词 3-d geoscience modeling solid mineral resource estimation of reserves surface modeling property modeling
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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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不同方法的BDS-3多频单点测速对比分析
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作者 耿涛 杨佳彬 谢新 《导航定位学报》 CSCD 2023年第4期56-62,共7页
针对北斗三号卫星导航系统(BDS-3)不同测速方法在不同环境下的测速性能缺乏全面评估的问题,提出一种BDS-3多频单点测速对比分析方法:利用BDS-3静态和动态数据,对比分析基于载波相位差分、多普勒、伪距差分方法的BDS-3不同频点静态和动... 针对北斗三号卫星导航系统(BDS-3)不同测速方法在不同环境下的测速性能缺乏全面评估的问题,提出一种BDS-3多频单点测速对比分析方法:利用BDS-3静态和动态数据,对比分析基于载波相位差分、多普勒、伪距差分方法的BDS-3不同频点静态和动态测速性能。实验结果表明:静态环境下,载波相位差分测速精度最好,可达到mm/s量级,伪距差分测速精度最差,为cm/s至dm/s量级;动态环境下,多普勒和载波相位差分测速的精度较好,水平方向可达到cm/s量级,高程方向约为1 dm/s,伪距差分测速误差较大;对不同频点的测速结果分析表明,BDS-3系统B1I、B1C、B2a、B2b、B3I等5个频点的测速精度基本在同一个量级。 展开更多
关键词 北斗三号卫星导航系统(BDS-3) 测速 多频 多普勒测速 载波相位差分
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顾及电离层延迟的BDS-3四频长基线定位算法 被引量:2
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作者 吕震 王振杰 +2 位作者 刘金萍 翟建朋 周浩 《测绘通报》 CSCD 北大核心 2023年第4期71-74,75-78,共8页
针对长基线定位中电离层延迟对定位精度造成的影响,本文提出了一种基于BDS-3四频信号(B1C/B1I/B2a/B3I)的四频消电离层(IF)组合方法,采用消电离层组合观测值消除电离层延迟误差,联合模糊度改正后的超宽巷或宽巷组合观测值构建定位方程,... 针对长基线定位中电离层延迟对定位精度造成的影响,本文提出了一种基于BDS-3四频信号(B1C/B1I/B2a/B3I)的四频消电离层(IF)组合方法,采用消电离层组合观测值消除电离层延迟误差,联合模糊度改正后的超宽巷或宽巷组合观测值构建定位方程,从而实现原始窄巷模糊度和基线位置坐标的解算。试验采用BDS-3四频数据对四频IF组合方法和基于GB-FCAR模型的电离层延迟参数估计方法的定位精度进行对比分析。结果表明,在对长度超过500 km的长基线进行定位解算时,四频IF组合方法可以实现电离层延迟误差消除。与电离层延迟参数估计方法相比,四频IF组合方法水平和垂直方向的定位精度均达分米级,提升幅度分别达35%和40%以上,定位精度显著提高,其相对定位精度可达1×10^(-9)m,满足长基线相对定位的要求。 展开更多
关键词 BDS-3 四频 长基线 参数估计 消电离层组合
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Depth estimation system suitable for hardware design
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作者 李贺建 左一帆 +3 位作者 杨高波 安平 王建伟 滕国伟 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期325-330,共6页
Depth estimation is an active research area with the developing of stereo vision in recent years. It is one of the key technologies to resolve the large data of stereo vision communication. Now depth estimation still ... Depth estimation is an active research area with the developing of stereo vision in recent years. It is one of the key technologies to resolve the large data of stereo vision communication. Now depth estimation still has some problems, such as occlusion, fuzzy edge, real-time processing, etc. Many algorithms have been proposed base on software, however the performance of the computer configurations limits the software processing speed. The other resolution is hardware design and the great developments of the digital signal processor (DSP), and application specific integrated circuit (ASIC) and field programmable gate array (FPGA) provide the opportunity of flexible applications. In this work, by analyzing the procedures of depth estimation, the proper algorithms which can be used in hardware design to execute real-time depth estimation are proposed. The different methods of calibration, matching and post-processing are analyzed based on the hardware design requirements. At last some tests for the algorithm have been analyzed. The results show that the algorithms proposed for hardware design can provide credited depth map for further view synthesis and are suitable for hardware design. 展开更多
关键词 3-d TV 3DTV) depth estimation hardware design rank transform census transform
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THE SYSTEM SIMULATION OF THREE-DIMENSIONAL RADAR 被引量:3
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作者 ZhangWei XiangJingcheng WangXuegang 《Journal of Electronics(China)》 2004年第5期407-412,共6页
To provide a test platform for Electronic Warfare (EW) system, it is needed to simulate the radar received Intermediate Frequency (IF) signals and radar system functions.This letter gives a description of a radar syst... To provide a test platform for Electronic Warfare (EW) system, it is needed to simulate the radar received Intermediate Frequency (IF) signals and radar system functions.This letter gives a description of a radar system simulation software developed for frequencyphase scanning three-dimensional (3-D) radar. Experimental results prove that the software could be used for system evaluation and for training purposes as an attractive alternative to real EW system. 展开更多
关键词 System simulation Electronic Warfare(EW) Three-dimensional(3-d) radars Intermediate frequency (IF) signals
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Two-Dimensional Interpolation Criterion Using DFT Coefficients
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作者 Yuan Chen Liangtao Duan +1 位作者 Weize Sun Jingxin Xu 《Computers, Materials & Continua》 SCIE EI 2020年第2期849-859,共11页
In this paper,we address the frequency estimator for 2-dimensional(2-D)complex sinusoids in the presence of white Gaussian noise.With the use of the sinc function model of the discrete Fourier transform(DFT)coefficien... In this paper,we address the frequency estimator for 2-dimensional(2-D)complex sinusoids in the presence of white Gaussian noise.With the use of the sinc function model of the discrete Fourier transform(DFT)coefficients on the input data,a fast and accurate frequency estimator is devised,where only the DFT coefficient with the highest magnitude and its four neighbors are required.Variance analysis is also included to investigate the accuracy of the proposed algorithm.Simulation results are conducted to demonstrate the superiority of the developed scheme,in terms of the estimation performance and computational complexity. 展开更多
关键词 2-d frequency estimation parameter estimation INTERPOLATION discrete Fourier transform
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Semi-Global Depth Estimation Algorithm for Mobile 3-D Video Applications
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作者 Qiong Liu Hongjiang Xiao 《Tsinghua Science and Technology》 EI CAS 2012年第2期128-135,共8页
Three-dimensional (3-D) video applications, such as 3-D cinema, 3DTV, ana Free Viewpomt Video (FVV) are attracting more attention both from the industry and in the literature. High accuracy of depth video is a fun... Three-dimensional (3-D) video applications, such as 3-D cinema, 3DTV, ana Free Viewpomt Video (FVV) are attracting more attention both from the industry and in the literature. High accuracy of depth video is a fundamental prerequisite for most 3-D applications. However, accurate depth requires computationally intensive global optimization. This high computational complexity is one of the bottlenecks to applying depth generation to 3-D applications, especially for mobile networks since mobile terminals usually have limited computing ability. This paper presents a semi-global depth estimation algorithm based on temporal consis- tency, where the depth propagation is used to generate initial depth values for the computationally intensive global optimization. The accuracy of initial depth is improved by detecting and eliminating the depth propagation outliers before the global optimization. Integrating the initial values without outliers into the global optimization reduces the computational complexity while maintaining the depth accuracy. Tests demonstrate that the algorithm reduces the total computational time by 54%-65% while the quality of the virtual views is essentially equivalent to the benchmark. 展开更多
关键词 3-d video depth estimation temporal propagation graph cuts
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Compute extremely low-frequency electromagnetic field exposure by 3-D impendance method
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作者 HAN Yu-nan LV Ying-hua ZHANG Hong-xin 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2007年第3期113-116,共4页
A 3-D impedance method has been introduced to compute the electric currents induced in a human body exposed to extremely low-frequency electromagnetic field. The 3-D impedance method has been deduced from Maxwell equa... A 3-D impedance method has been introduced to compute the electric currents induced in a human body exposed to extremely low-frequency electromagnetic field. The 3-D impedance method has been deduced from Maxwell equations and is put into the computation and simulation effectively to the visible human body model, which has 196×114×626 cells and more than 40 types of tissues. As the result, two representative cases are investigated. One is exposure of the human body to 100 μT (1 000 mG), the limit recommended by the International Commission on Non-Ionizing Radiation Protection for the public and the other one is the exposure of human body to 0.4 laT (4 mG), the level at which a statistical link appears with a doubled risk of development of childhood leukaemia. The distribution of induced current density can be obtained and the maximum of induced current are found to be 16 mA/m^2 and 0.07 mA/m^2. 展开更多
关键词 3-d impedance method induced current magnetic flux density visible human body model extremely low frequency (ELF)
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宽频段相干信号三维参数联合估计的新算法 被引量:1
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作者 杜刚 姜新迎 +1 位作者 王永良 张永顺 《信号处理》 CSCD 北大核心 2008年第6期908-911,共4页
基于非均匀的L型阵列,本文提出了一种宽频段相干信号频率和二维到达角联合估计的时空二维处理新方B法—WTSS(wide-band time-space smoothing)算法。该算法能精确地估计具有相同数字频率的相干信号的三维参数,无需多维谱峰搜索,具有计... 基于非均匀的L型阵列,本文提出了一种宽频段相干信号频率和二维到达角联合估计的时空二维处理新方B法—WTSS(wide-band time-space smoothing)算法。该算法能精确地估计具有相同数字频率的相干信号的三维参数,无需多维谱峰搜索,具有计算量小,参数自动配对的优点。另外,在WTSS算法的基础上,利用L型阵列的特点进行分维处理,成功地实现了具有频率兼并现象的相干信号的三维参数估计。该算法能够并行实现以进一步增强其实时性。计算机仿真结果验证了算法的有效性。 展开更多
关键词 宽频段 相干源 三维参数估计 平滑技术
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宽频段空间相干信号三维参数联合估计算法 被引量:1
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作者 杜刚 张永顺 姜新迎 《空军工程大学学报(自然科学版)》 CSCD 北大核心 2008年第2期36-38,91,共4页
基于非均匀的L型阵列,提出一种宽频段相干信号频率和二维到达角联合估计的新方法——JSDOA算法。该算法利用阵列时空数据构造了一个平滑的波达矩阵,通过对其进行特征分解估计出相干信号的三维参数。该算法能精确地估计具有相同数字频率... 基于非均匀的L型阵列,提出一种宽频段相干信号频率和二维到达角联合估计的新方法——JSDOA算法。该算法利用阵列时空数据构造了一个平滑的波达矩阵,通过对其进行特征分解估计出相干信号的三维参数。该算法能精确地估计具有相同数字频率的相干信号的三维参数,避免了阵列孔径损失,具有计算量小,三维参数自动配对的优点。计算机仿真结果验证了算法的有效性。 展开更多
关键词 宽频段 相干源 三维参数估计 平滑技术
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P-Ⅲ型分布参数估计的地区贝叶斯方法
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作者 黄伟军 丁晶 赵永龙 《成都科技大学学报》 EI CAS CSCD 1996年第5期6-11,36,共7页
提出了一种分阶段,分层次地估计P-Ⅲ型分布的均值EX、变差系数CV和偏态系数CS的地区贝叶斯方法(RBM)。统计试验结果表明,RBM的统计性能要优于传统的优化适线法和概率权重矩法等参数估计方法。
关键词 洪水频率 P-Ⅲ型分布 参数估计 地区贝叶斯方法
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基于均匀圆阵的相干源三维参数估计算法
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作者 姜新迎 冯有前 杜刚 《无线电通信技术》 2008年第6期41-43,共3页
基于均匀圆阵,提出了一种宽频段信号频率和二维到达角联合估计的新方法—CTDS算法。通过对构造的波达矩阵进行特征分解,该算法能精确地估计具有相同数字频率的相干信号的三维参数,无需多维谱峰搜索,具有计算量小,三维参数自动配对的优... 基于均匀圆阵,提出了一种宽频段信号频率和二维到达角联合估计的新方法—CTDS算法。通过对构造的波达矩阵进行特征分解,该算法能精确地估计具有相同数字频率的相干信号的三维参数,无需多维谱峰搜索,具有计算量小,三维参数自动配对的优点。另外,算法通过增加延迟抽头级数解相干,因此避免了通常的降维解相干算法引起的阵列孔径损失,同时减少了所需的阵元数。计算机仿真结果验证了算法的有效性。 展开更多
关键词 宽频段 相干源 均匀圆阵 三维参数估计
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基于子空间和投影分离的三维正弦信号频率估计算法 被引量:2
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作者 黄龙庭 吴云韬 +1 位作者 廖桂生 张彦铎 《电子学报》 EI CAS CSCD 北大核心 2012年第6期1223-1228,共6页
本文提出了一种基于子空间和投影分离的三维正弦信号的频率参数估计算法.算法核心思想在于将三维采样数据阵理解为散布在某一维上的二维切片矩阵列,以此来实现对三维采样数据阵列的降维处理,并通过构造投影矩阵来实现信号中各分量的分离... 本文提出了一种基于子空间和投影分离的三维正弦信号的频率参数估计算法.算法核心思想在于将三维采样数据阵理解为散布在某一维上的二维切片矩阵列,以此来实现对三维采样数据阵列的降维处理,并通过构造投影矩阵来实现信号中各分量的分离,算法可实现信号各分量三维参数自动配对.在整个估计过程中,算法所用矩阵都维持原采样数据阵规模,因而算法整体运算量较小.计算机仿真结果表明所提算法在性能及运算复杂度上均要优于三维情况下的IMDF算法及HOSVD算法. 展开更多
关键词 三维频率估计 子空间方法 投影矩阵分离方法
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Modeling the Seakeeping Performance of Luxury Cruise Ships 被引量:4
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作者 曹宇 俞宝均 王建方 《Journal of Marine Science and Application》 2010年第3期292-300,共9页
The seakeeping performance of a luxury cruise ship was evaluated during the concept design phase.By comparing numerical predictions based on 3-D linear potential flow theory in the frequency domain with the results of... The seakeeping performance of a luxury cruise ship was evaluated during the concept design phase.By comparing numerical predictions based on 3-D linear potential flow theory in the frequency domain with the results of model tests, it was shown that the 3-D method predicted the seakeeping performance of the luxury cruise ship well.Based on the model, the seakeeping features of the luxury cruise ship were analyzed, and then the influence was seen of changes to the primary design parameters (center of gravity, inertial radius, etc.).Based on the results, suggestions were proposed to improve the choice of parameters for luxury cruise ships during the concept design phase.They should improve seakeeping performance. 展开更多
关键词 luxury cruise ship seakeeping performance 3-d linear potential flow theory frequency domain design parameters
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MouseVenue3D:A Markerless Three-Dimension Behavioral Tracking System for Matching Two-Photon Brain Imaging in Free-Moving Mice 被引量:2
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作者 Yaning Han Kang Huang +8 位作者 Ke Chen Hongli Pan Furong Ju Yueyue Long Gao Gao Runlong Wu Aimin Wang Liping Wang Pengfei Wei 《Neuroscience Bulletin》 SCIE CAS CSCD 2022年第3期303-317,共15页
Understanding the connection between brain and behavior in animals requires precise monitoring of their behaviors in three-dimensional(3-D)space.However,there is no available three-dimensional behavior capture system ... Understanding the connection between brain and behavior in animals requires precise monitoring of their behaviors in three-dimensional(3-D)space.However,there is no available three-dimensional behavior capture system that focuses on rodents.Here,we present MouseVenue3D,an automated and low-cost system for the efficient capture of 3-D skeleton trajectories in markerless rodents.We improved the most time-consuming step in 3-D behavior capturing by developing an automatic calibration module.Then,we validated this process in behavior recognition tasks,and showed that 3-D behavioral data achieved higher accuracy than 2-D data.Subsequently,MouseVenue3D was combined with fast high-resolution miniature two-photon microscopy for synchronous neural recording and behavioral tracking in the freely-moving mouse.Finally,we successfully decoded spontaneous neuronal activity from the 3-D behavior of mice.Our findings reveal that subtle,spontaneous behavior modules are strongly correlated with spontaneous neuronal activity patterns. 展开更多
关键词 Computational neuroethology Behavioral and neural recording 3-d pose estimation Multi-view cameras Automatic calibration
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