...Perrig
aperrig@di.epfl.ch
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...Gros
Bertrand.Gros@di.epfl.ch
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...Bruschini
Claudio.Bruschini(AT)epfl.ch
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...Mächler
maechler@di.epfl.ch
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...meter
Typically 0.2 - 0.3 meter under ``normal'' conditions
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...depth
When calculating the time necessary to see structures x meters deep, we should not forget that the returning signal also needs to traverse those x meters, doubling the recording time
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...EMPA
EMPA is the Eidgenössische Material Prüfanstalt, Federal Material Testing Agency
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...bit
The 8 bit signify that the intensity values are encoded with 8 bit precision
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...hyperbola
By geometric construction, it can be shown that a point scatterer appears as a hyperbola on the GPR image, having an opening of 9#9 and the parameters a=1 and b=1
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...filter
A 5 by 3 median filter takes a neighborhood of 5 pixels in the vertical and 3 pixels in the horizontal direction. Those 15 pixels are sorted after their intensities and the 8th pixel (the median) in that sorted list will replace the current pixel in the image
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...image
In the real case, we use a neuron with a continuous output, where values greater than 0.6 represent yes, outputs less than 0.4 no and ``don't know'' in between
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...quality
Good quality means ``hand chosen'' and that the position of the mine is well known
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Adrian Perrig
Wed Jun 5 22:28:55 MET DST 1996