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Department of Statistics, The Ohio State University
Statistics and Biostatistics Colloquium Series
Polar Cloud Detection Using Satellite Data with Analysis and Application of Kernel Methods
Tao Shi
Department of Statistics
University of California at Berkeley
3:30PM - Thursday, February 24, 2005
Room 170, Eighteenth Avenue Bldg. (EA 170)
ABSTRACT
Cloud detection is critical step for improving our scientific
understanding of ongoing natural and human-induced global climate
change. However, clouds above snow- and ice-covered surfaces over polar
regions are especially difficult to detect because their temperature and
reflectivity are similar to that of the surface. In this talk, we
provide efficient algorithms to detect polar clouds using data from
NASA's Earth Observing System. We first developed a fast algorithm to
distinguish cloud from snow and ice, using the data provided by the
Multi-angle Imaging SpectroRadiometer (MISR). We also proposed another
method fusing the data from MISR and the Moderate Resolution Imaging
Spectroradiometer (MODIS) to improve the polar cloud detection for both
sensors.
Motivated by the satellite data fusion problem, we studied the machine
learning algorithms using a Gaussian kernel. We showed that the leading
eigen-vectors of a Gaussian kernel represent the clusters of the data.
Based on this relationship, we provided a unified view of the Gaussian
kernel related machine learning algorithms including Semi-supervised
learning algorithms, Kernel Principle Component Analysis, Spectral
Clustering, and Support Vector Machines.
Meet the speaker in Room 212 Cockins Hall at 4:30 p.m. Refreshments will be served.
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