Geoscience Reference
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Fig. 5 Ongoing dike breach
with projected grid and both
surface waves and light
reflections
using a rectangular grid projection and a set of four cameras. Preliminary tests
confirmed the general adaptability of the AICON system to the dike breach
problem. The three-dimensional breach profiles were directly computed from the
camera images. Preliminary tests provide motivating results and a feasible, non-
intrusive method seems therefore to be available for determination of a sediment
surface topography during a spatial dike breach.
Several issues regarding the test setup have to be improved for a complete
application of the technique, however. Surface waves and light reflections disturb
the projected grid and complicate the optical grid visibility. The accuracy depends
essentially on the water quality, on the reflection pattern by the water and on the
sediment light adsorption characteristics. Black or white
artificial
sediment would
be an optimum because of its excellent contrast qualities in addition to the small
amount of impurities. An adaption of test setup and a detailed analysis of the derived
data are currently in progress.
Acknowledgment The writer was supported by the Swiss National Science Foundation, Grant
No. 200020-116680.
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