• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2003.10a
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• pp.15-19
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• 2003

The Total Least Squares (TLS) method is introduced in comparison with the conventional Least Squares (LS) method. The principles and mathematical models for both methods are summarized and the comparison results from their applications to a simple geometric example, fitting a straight line to a set of 2D points are presented. As conceptually reasoned, the results clearly indicate that LS is more susceptible of producing wrong parameters with worse precision rather than TLS. For many applications in surveying, can adjustment computation and parameter estimation based on TLS provide better results.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.1
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• pp.99-107
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• 2016

In order to maintain the precise positioning accuracy of the VLBI system, the shape deformation found in antenna structure should be monitored. In fact, reduced the antenna gaining of an electromagnetic wave reception from the Quasar has been particularly expected due to the shape deformation of main reflector in VLBI antenna. Therefore, the importance of shape deformation monitoring for the main reflector has been significantly increased. The main reflector has come out as the high potential for deformation in the VLBI structure. The fact has led us to investigate the monitoring system for the main reflector based on the efficient algorithm in accordance with the close-range photogrammetry, which of expecting to be utilized as the continuous and automated monitoring system for the structure deformation in the near future. Ten fitting lines were estimated with the TLS for feature points of distributed in all directions from the main reflector. The resultant intersection point of estimated fitting lines was calculated by using the nearest point calculation algorithm, based on those non-intersection lines. Following to the intuitive basis for the time series analysis, the results was able to provide the calculation of numerical variation in the intersection point, which is represented in 3-axis,; that we are expecting to open the way for predicting a deformation rate as well as deformation direction