My research group develops models and algorithms for large-scale inverse problems, especially image reconstruction for X-ray CT and MRI.  The models include those based on sparsity using dictionaries learned from large-scale data sets.  Developing efficient and accurate methods for dictionary learning is a recent focus.

To see how model-based image reconstruction methods lead to improved image quality and/or lower X-ray doses, see: http://web.eecs.umich.edu/~fessler/rehttp://web.eecs.umich.edu/~fessler/result/ct/