The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B5. Beijing 2008 
595 
• The results achieved with the 100 m dataset are sensibly 
better than those of the 200 m dataset. The mean of the 
absolute errors of the 200 m dataset is approximately two 
times bigger than that of the 100 m dataset. 
• Considering the displacement errors, there are not 
remarkable differences between the three main components. 
To conclude* the first results obtained with the least squares 
curve matching have been presented. They concern simulated 
data, and were mainly used to test the matching capabilities and 
improve different aspects of the matching algorithm, like the 
outlier rejection. The achieved results using synthetic data are 
encouraging. Future work will involve the test of the proposed 
approach using real data. The usefulness of curve matching for 
deformation studies, say the added value with respect to surface 
matching, has to be proved. 
ACKNOWLEDGMENTS 
The matching results shown in this work were achieved by 
using the LS3D Surface Matching software of the Chair of 
Photogrammetry and Remote Sensing of the Swiss Federal 
Institute of Technology Zurich, which was kindly provided for 
academic purposes to the Institute of Geomatics by Prof. Armin 
Gruen and Devrim Akca. The authors thank Prof. Jaume Calvet 
and David García of the RISKNAT group, the natural hazards 
research group of the University of Barcelona, for the data 
acquisition for the main experiment described in this work. 
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