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11.
正规化矩阵正定时半参数估计量的统计性质 总被引:12,自引:0,他引:12
利用补偿最小二乘原理构造加权惩罚平方和,得到半参数模型中正规化矩阵正定时参数和半参数的估计量.从偶然误差的统计特征出发,详细讨论这种平差方法得到的参数估值的一些统计性质,并对半参数平差与最小二乘法的参数估计值进行比较.理论分析表明,通过选取合适的平滑参数,半参数平差方法优于最小二乘法.另外从数理统计的角度对平滑参数的选取进行分析,得到平滑参数的取值范围,也给出了平滑参数对模型精度的影响. 相似文献
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This paper systematically studies the statistical diagnosis and hypothesis testing for the semiparametric linear regression model according to the theories and methods of the statistical diagnosis and hypothesis testing for parametric regression model.Several diagnostic measures and the methods for gross error testing are derived.Especially,the global and local influence analysis of the gross error on the parameter X and the nonparameter s are discussed in detail;at the same time,the paper proves that the d... 相似文献
15.
测量平差函数模型的若干讨论 总被引:7,自引:0,他引:7
孙海燕 《武汉大学学报(信息科学版)》2003,(Z1)
讨论了测量平差函数模型的几种形式———参数模型、非参数模型及半参数模型 ,分别论述了各种模型的优缺点及其适用范围。半参数模型对于客观实际具有极强的解释能力 ,应给予充分的重视和深入的研究。 相似文献
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地球质心运动的频谱分析方法 总被引:1,自引:0,他引:1
针对地球质心运动主要是由多种周期运动叠加的特点,依次讨论了谱分析方法中的AR模型谱分析和小波谱分析方法,分别指出:将参数谱分析方法中的AR模型谱分析和非参数谱分析中的小波谱分析相结合产生的小波-AR谱分析以及小波包-AR谱分析方法,在地球质心运动的谱分析中有较好的频率分辨率以及噪声抑制能力。 相似文献
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PANHeping ZHANGChunsen 《地球空间信息科学学报》2003,6(2):48-54
This paper describes the structure,geometric model and geo-metric calibration of Photogrammetron I-the first type of photogrammetron which is designed to be a coherent stereo photogrammetric system in which two cameras are mounted on a physical base but driven by an intelligent agent architecture.The system calibration is divided into two parts:the in-lab calibration determines the fixed parameters in advance of system operation,and the insitu calibration keeps tracking the free parameters in real-time during the system operation.In a video surveillance set-up, prepared control points are tracked in stereo image sequences,so that the free parameters of the system can be continuously updated through iterative bundle adjustment and kalman filtering. 相似文献
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The paper deals with measurement of human facial deformations from synchronized image sequences taken with multiple calibrated cameras from different viewpoints. SIFT (Scale Invariant Feature Transform) keypoints are utilized as image feature points in the first place to determine spatial and temporal correspondences between images. If no temporal match is found for an image point by keypoint matching, then the tracking of the point is switched to least squares matching provided the point has one or more spatial corresponding points in the other views of the previous frame. For this purpose, a new method based on affine multi-image least squares matching is proposed where multiple spatial and temporal template images are simultaneously matched against each search image and part of the spatial template images also change during adjustment. A new method based on analyzing temporal changes in the image coordinates of the tracked points in multiple views is then presented for detecting the 3-D points which move only rigidly between consecutive frames. These points are used to eliminate the effect of rigid motion of the head and to obtain the changes in the 3-D points and in the corresponding image points due to pure deformation of the face. The methods are thoroughly tested with three multi-image sequences of four cameras including also quite large changes of facial deformations. The test results prove that the proposed affine multi-image least squares matching yields better results than another method using only fixed templates of the previous frame. The elimination of the effect of rigid motion works well and the points where the face is deforming can be correctly detected and the true deformation estimated. A method based on a novel adaptive threshold is also proposed for automated extraction and tracking of circular targets on a moving calibration object. 相似文献
19.
This paper describes the structure, geometric model and geometric calibration of Photogrammetron I—the first type of photogrammetron which is designed to be a coherent stereo photogrammetric system in which two cameras are mounted on a physical base but driven by an intelligent agent architecture. The system calibration is divided into two parts: the in-lab calibration determines the fixed parameters in advance of system operation, and the in-situ calibration keeps tracking the free parameters in real-time during the system operation. In a video surveillance set-up, prepared control points are tracked in stereo image sequences, so that the free parameters of the system can be continuously updated through iterative bundle adjustment and Kalman filtering. 相似文献
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针对当前丰富多样的DEM地形综合模型,分类阐述其综合原理、关键技术及优缺点,以黄土丘陵1:1万DEM为基础,对其地形综合效果进行对比分析。研究结果表明:现有的DEM地形综合模型各有优缺点;不同综合模型综合后的地形,高程数值随着综合尺度的增加,存在显著差异,而且不同综合模型对流域边界的综合处理也存在显著差异,没有形成客观有效的流域边界描述;当前困扰DEM地形综合的关键问题,是缺乏不同尺度下地形综合质量的客观评价标准,致使现有综合模型地形综合结果和DEM格网分辨率之间没有建立本应存在的内在联系,有待进一步深入研究。 相似文献