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Institution

State Bureau of Surveying and Mapping

About: State Bureau of Surveying and Mapping is a based out in . It is known for research contribution in the topics: Terrain & Pixel. The organization has 277 authors who have published 206 publications receiving 2044 citations.


Papers
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Journal ArticleDOI
TL;DR: In this paper, repeated measurements across a 90-sites global positioning system network in Central Asia provide direct evidence of current high rates of tectonic deformation far north of the India-Eurasia suture zone.

214 citations

Journal ArticleDOI
TL;DR: It is concluded that significant changes in land use/land cover have occurred in the Three Gorges Reservoir Area and the main cause is a continuous economic and urban/rural development, followed by environmental management policies after construction of the Three gorges Dam.

131 citations

Journal ArticleDOI
TL;DR: Wang et al. as discussed by the authors proposed an iterative method of weighted TLS adjustment to solve EIV model based on Newton-Gauss approach of non-linear weighted least-squares (WLS) adjustment.
Abstract: Total least-squares (TLS) adjustment is used to estimate the parameters in the errors-in-variables (EIV) model. However, its exact solution is rather complicated, and the accuracies of estimated parameters are too difficult to analytically compute. Since the EIV model is essentially a non-linear model, it can be solved according to the theory of non-linear least-squares adjustment. In this contribution, we will propose an iterative method of weighted TLS (WTLS) adjustment to solve EIV model based on Newton–Gauss approach of non-linear weighted least-squares (WLS) adjustment. Then the WLS solution to linearly approximated EIV model is derived and its discrepancy is investigated by comparing with WTLS solution. In addition, a numerical method is developed to compute the unbiased variance component estimate and the covariance matrix of the WTLS estimates. Finally, the real and simulation experiments are implemented to demonstrate the performance and efficiency of the presented iterative method and its linearly approximated version as well as the numerical method. The results show that the proposed iterative method can obtain such good solution as WTLS solution of Schaffrin and Wieser (J Geod 82:415–421, 2008) and the presented numerical method can be reasonably applied to evaluate the accuracy of WTLS solution.

127 citations

Journal ArticleDOI
TL;DR: Wang et al. as mentioned in this paper presented an approach for the detection of buildings that have collapsed in an earthquake based on 3D geometric changes, particularly height change of the buildings, using pre- and post-seismic IKONOS stereo image pairs.
Abstract: To address the disadvantage of traditional methods providing only two-dimensional (2D) damage change of the collapsed buildings, this paper presents an approach for the detection of the buildings that have collapsed in an earthquake based on 3D geometric changes, particularly height change of the buildings, using pre- and post-seismic IKONOS stereo image pairs. One of the critical issues – the accuracy of the 3D ground point determination from high-resolution satellite imagery (HRSI) – is first addressed employing a bias-compensation model based on the rational function polynomial coefficient bundle adjustment. With the refined 3D ground coordinates, two ways of detecting the collapsed buildings are proposed: (1) detection of an individual collapsed building by comparing the height differences at the corner points of the building calculated from the pre- and post-seismic IKONOS stereo pairs and (2) determination of the region of collapsed buildings by calculating the difference between the pre- and post-seismic digital elevation models (DEMs) generated again from the pre- and post-seismic stereo images. At the same time, a pre-seismic DEM based on a topographical map is generated for detection comparison in the study. The experiment results for Dujiangyan using two IKONOS stereo pairs before and after the Wenchuan earthquake demonstrated the following. (1) Accuracy of better than 1.1 m in planimetry and 1.5 m in height can be achieved from the pre- and post-seismic IKONOS stereo image pairs using the affine bias compensation model. This accuracy guarantees the feasibility of detecting the 3D geometric changes of the earthquake-induced building collapses from pre- and post-seismic HRSI stereo images. (2) Using the refined 3D coordinates of the ground points computed from the pre- and post-seismic IKONOS stereo pairs, the status (i.e., totally collapsed, partially collapsed or not collapsed) and the number of collapsed storeys can be estimated for an individual building being assessed. (3) The region of collapsed buildings can be determined by differencing the pre- and post-seismic DEMs created from the pre- and post-seismic IKONOS stereo pairs. An overall accuracy of better than 90% is achieved for the detection of the collapsed buildings based on the difference DEM using the pixel- and object-based assessment methods.

125 citations

Journal ArticleDOI
TL;DR: In this paper, the authors introduce quaternions to represent rotation parameters and derive the formulae to compute quaternion, translation and scale parameters in the Bursa-Wolf geodetic datum transformation model from two sets of co-located 3D coordinates.
Abstract: This paper briefly introduces quaternions to represent rotation parameters and then derives the formulae to compute quaternion, translation and scale parameters in the Bursa–Wolf geodetic datum transformation model from two sets of co-located 3D coordinates. The main advantage of this representation is that linearization and iteration are not needed for the computation of the datum transformation parameters. We further extend the formulae to compute quaternion-based datum transformation parameters under constraints such as the distance between two fixed stations, and develop the corresponding iteration algorithm. Finally, two numerical case studies are presented to demonstrate the applications of the derived formulae.

72 citations


Authors

Showing all 277 results

NameH-indexPapersCitations
Xiang Li97147242301
Haixia Zhang483328876
Feng Bao473468907
Xiaohua Tong323324855
Bofeng Li271292267
Huan Xie241371728
Jinyun Guo191241219
Yunzhong Shen19751177
Shijie Liu18811135
Teng Fei1863921
Guo Zhang17116963
Xiangguo Lin1525858
Zhen Ye1459608
Junbo Shi1438598
Zhonghua Hong1262586
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
20203
20195
20183
20175
20165
20158