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Wang L.,East China Institute of Technology | Wang L.,Jiangxi Province Key Laboratory for Digital Land | Yu D.,East China Institute of Technology
Cehui Xuebao/Acta Geodaetica et Cartographica Sinica | Year: 2014

A new virtual observation method to ill-posed total least squares (TLS) problem is proposed. The priori information is taken as one class of virtual independent observations, and then the virtual observations as constraints with ill-posed observation equation are united together to solve the unknown parameters. The iterative algorithm and ridge mark method for determining sub-criterion-parameter of virtual observation method are given. Through two examples, the TLS-virtual observation method, TLS-L curve method, common TLS method and LS method are compared and analyzed. At last, the conclusion that virtual observation method to ill-posed TLS problem is very effective is obtained.


Guo J.,Anhui Agricultural University | Guo J.,Jiangxi Province Key Laboratory for Digital Land
Cehui Xuebao/Acta Geodaetica et Cartographica Sinica | Year: 2014

A more concise formula of the meridian arc length was obtained by introduced two new parameters: the third flattening and the Gauss hypergeometric function. From another perspective, the simplified formula is also can be explained by a Taylor series expansion. By this, we got error estimate of the formula in terms of the Lagrange form of the remainder. For numerical verification of the error estimate theory, application example was presented by using the WGS84 data. The results show that experimental data are consistent with the error estimate theory and the simplified formula is more precise than the standard one.


Wang L.,East China Institute of Technology | Wang L.,Jiangxi Province Key Laboratory for Digital Land | Wang L.,Key Laboratory of Watershed Ecology and Geographical Environment Monitoring | Yu D.,East China Institute of Technology | Lu K.,East China Institute of Technology
Cehui Xuebao/Acta Geodaetica et Cartographica Sinica | Year: 2015

On the basis of complex least squares adjustment method (CLSAM), the theory of complex total least squares adjustment method (CTLSAM) is proposed. The algorithms of complex total least squares and complex LS-TLS method are derived. Through two examples, the complex LS method under the adjustment criterions that minimize the sum of squares of the module of observation vector residual (adjustment criterion 1) and the sum of squares of the real part and imaginary part of the observation vector (adjustment criterion 2), the complex TLS method under the adjustment criterions that minimize the sum of squares of the module of observation vector and coefficient matrix residual (adjustment criterion 3) and the sum of squares of the real part and imaginary part of the observation vector and coefficient matrix residual (adjustment criterion 4) are compared and analyzed respectively. The results of two examples show that the CLSAM under the adjustment criterion 1 is more reasonable than the adjustment criterion 2; the CTLSAM under the adjustment criterion 3 is more accurate than the adjustment criterion 4; the CTLSAM under the adjustment criterion 3 is better than the CLSAM under the adjustment criterion 1 when the coefficient matrix contains stochastic noise. ©, 2015, SinoMaps Press. All right reserved.


Wang L.,East China Institute of Technology | Wang L.,Key Laboratory of Watershed Ecology and Geographical Environment Monitoring of NASG | Wang L.,Jiangxi Province Key Laboratory for Digital Land | Yu H.,East China Institute of Technology | And 3 more authors.
Cehui Xuebao/Acta Geodaetica et Cartographica Sinica | Year: 2016

A new thinking for solving partial errors-in-variables (partial EIV) model was proposed. Through the transposition processing in partial EIV model, a new functional model was reconstructed. Adjustment of indirect observations has been used two times to calculate the model parameters and the stochastic elements in coefficient matrix, translating total least squares problem to least squares problem. It also achieves high convergence rate through some simple variables transformation. Finally, real and simulation data were implemented to compare with the existing algorithms and to analysis the applicability of the proposed algorithms. The results show that the new algorithms are feasible and it can achieve the same values with the existing algorithms. © 2016, Surveying and Mapping Press. All right reserved.


Wang L.,East China Institute of Technology | Wang L.,Wuhan University | Wang L.,Jiangxi Province Key Laboratory for Digital Land | Xu C.,Wuhan University | Wen Y.,Wuhan University
Cehui Xuebao/Acta Geodaetica et Cartographica Sinica | Year: 2013

While gross errors are contained in the observations, through the use of InSAR coseismic deformation data obtained from the ESA Envisat/ASAR images and with LN algorithm, the fault parameters of Okada rectangle dislocation model in the elastic half-space can be calculated for Qinghai Dacaidan Mw6.3 earthquake on 10 November, 2008. The earthquake fault inversion results of depth, dip, length, width, dip-slip, center longitude, center latitude, and strike azimuth are 19.6915 km, 56.8923°, 16.4993 km, 6.8548 km, 0.8326 m, 95.8847°, 37.5295°, and 116.4115° respectively. And the inverted geodetic seismic moment is 3.1084×1018Nm (Mw6.2950), which is consisting with the seismic results. The inversion results has proved that when the observations are contaminated by gross errors, using LN algorithm to deal with structured total least norm problems in L1 norm can effectively drop off the interference caused by those errors, and can fully make use of the prior information and at the same time consider the effects of coefficient matrix errors caused by reasons such as surveying, linearization and so on.


Wang L.,East China Institute of Technology | Wang L.,Wuhan University | Wang L.,Jiangxi Province Key Laboratory for Digital Land | Xu C.,Wuhan University
Wuhan Daxue Xuebao (Xinxi Kexue Ban)/Geomatics and Information Science of Wuhan University | Year: 2013

The achievements and new progresses in the estimation properties, algorithms, and applications of total least squares in the recent decade are summarized in this paper. Related algorithms and applications of total least squares for processing surveying data are discussed. Moreover, the prospects for algorithms and application of total least squares in geodetic inversion are discussed.


Zhan X.,Central South University | Zhan X.,Nanchang Institute of Technology | Zhan X.,Jiangxi Province Key Laboratory for Digital Land | Dai W.,Central South University | Zhou S.,Jiangxi Academy of science
Journal of Information and Computational Science | Year: 2014

There are relativity problem among the impact factors which effect dam deformation, morbid result would be caused when these factors are used to build the regression model, and the stability of model which is used to analysis and forecast the deformation of dam will be affected. Independent Components Analysis (ICA) combining with regression analysis can be used in dam deformation analysis owing ICA's potential to remove relativity and provide statistical independence between factors. The simulation experiment and example showed that Independent Components Regression (ICR) can solve the relativity problem of the impact factors, and can give better explanation to the dependent variable. The ICR is a new way and has great potential applications in the field of deformation analysis. © 2014 Binary Information Press.


Zhao Q.,Xuzhou Normal University | Zhao Q.,Jiangxi Province Key Laboratory for Digital Land | Zhou X.,Xuzhou Normal University
Applied Mechanics and Materials | Year: 2012

In the analysis of dam displacement data, mostly, a single point is used for calculation. Based on the concept named Time-displacement, this paper proposes a new calculation method with multi-point, which can make up the scarcity of analysis on the data of the dam deformation for a long time. Based on the concept of Time-displacement, the method of building the multi-point model is as follows: firstly, according to the deformation monitoring period, displacement data of all monitoring points on the deformation body, can be converted into the displacement rate. And based on displacement rate value, an appropriate rate threshold can be chosen; the rate threshold based on the experience can be used many also. Then the number of every monitoring point exceeding the rate threshold throughout the monitoring period can be recorded, and according to the number, the monitoring points' Time-displacement could be divided into different levels. If the number of monitoring points on the deformation body is less, the interpolation points would be laid along the direction of the original monitoring sites. By the method of decision tree classification, the interpolation points' Time-displacement could be figured out. Finally, with the original monitoring points and the interpolation points, the figure about deformation body's Time-displacement could be drawn, which can reflect the displacement situation about the deformation body more dynamically. © (2012) Trans Tech Publications, Switzerland.


Lei R.,Zhengzhou Institute of Surveying and Mapping | Ji S.,Jiangxi Province Key Laboratory for Digital Land
Lecture Notes in Electrical Engineering | Year: 2012

In this paper, CCD array displacement and rotation model, focal length displacement model and optical distortion model were analyzed for line-array CCD sensor of high resolution satellites. An integrated interior self-calibration model was then proposed. Applying piecewise polynomial interpolation model, contents of exterior parameters to be calibrated were analyzed. Based on collinearity equation, a self-calibration bundle block adjustment model was constructed and relative solution method was given. Through SPOT5 simulation datasets, block adjustment experiments were done and the experimental results verified the feasibility of the solution model. © 2012 Springer-Verlag Berlin Heidelberg.


Wu X.,Zhengzhou University | Wu X.,Jiangxi Province Key Laboratory for Digital Land | Zhang Y.,Zhengzhou University | Yu Y.,Zhengzhou University | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

Considering the aging and radiation recession of satellite remote senors on-orbit, regular in-orbit calibration is essential to updating the calibration parameters and improving the data's quantitative application level. This paper reviews the existing on-orbit radiometric calibration methods, and introduces famous radiation calibration fields around the world. Simultaneous ground measurement was carried out for the calibration of visible-near infrared bands of HJ-1B satellite. A comparison was made between the results of the experiment and the calibration parameters released along with environmental satellite images, which represents desirable validity and applicability. The calibration result determined the sensor recession and aging in in-orbit operation. Finally, reasonable proposals for the quantitative application of satellite data are given. © 2014 Copyright SPIE.

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