Engineering topics

Chartrand, Rick

Publications and source records attributed to Chartrand, Rick.

3 records

DOE OSTI2015

Image fusion using sparse overcomplete feature dictionaries

Approaches for deciding what individuals in a population of visual system "neurons" are looking for using sparse overcomplete feature dictionaries are provided. A sparse overcomplete feature dictionary may be learned for an image dataset and a local sparse representation of the image dataset may be built using the learned feature dictionary. A local maximum pooling operation may be applied on the local sparse representation to produce a translation-tolerant representation of the image dataset. An object may then be classified and/or clustered within the translation-tolerant representation of the image dataset using a supervised classification algorithm and/or an unsupervised clustering algorithm.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2013

Nonconvex Optimization and the High-Dimensional Geometry of Video [Slides]

Minimizing nonconvex penalty functions often produces better sparse solutions than ℓ 1 minimization. Using p-shrinkage and splitting allows this to be done very efficiently. Matrix decomposition methods can extract interesting features from high-dimensional data without explicit modeling. Important unsolved problems remain.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2012

Image processing and reconstruction [Slides]

This talk will examine some mathematical methods for image processing and the solution of underdetermined, linear inverse problems. The talk will have a tutorial flavor, mostly accessible to undergraduates, while still presenting research results. The primary approach is the use of optimization problems. We will find that relaxing the usual assumption of convexity will give us much better results.

97 MATHEMATICS AND COMPUTING↗