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Search Publications by: Alfred S Carasso (Fed)

Displaying 26 - 50 of 68

HAZARDOUS CONTINUATION BACKWARD IN TIME IN NONLINEAR PARABOLIC EQUATIONS AND AN EXPERIMENT IN DEBLURRING NONLINEARLY BLURRED IMAGERY

April 25, 2013

Author(s)

Alfred S. Carasso

Identifying sources of ground water pollution, and deblurring nanoscale imagery, as well as astronomical galaxy images, often involves the numerical computation of parabolic equations backward in time. However, very little computational experience has so

Alternative methods of latent fingerprint enhancement and metrics for comparing them

January 14, 2013

Author(s)

Alfred S. Carasso

Digital enhancements of latent fingerprints using Photoshop processing is the preferred methodology among law enforcement forensic experts. This report explores alternative enhancement methods that are independent of Photoshop, relying instead on such

Reconstructing the past from imprecise knowledge of the present: Some examples of non uniqueness in solving parabolic equations backward in time.

May 24, 2012

Author(s)

Alfred S. Carasso

Identifying sources of ground water pollution, and deblurring astronomical galaxy images, are two important applications generating growing interest in the numerical computation of parabolic equations backward in time. However, while backward uniqueness

Fractional Diffusion, Low Exponent Levy Stable Laws, and Slow Motion Denoising of Helium Ion Microscope Nanoscale Imagery

February 22, 2012

Author(s)

Andras Vladar, Alfred S. Carasso

Helium ion microscopes (HIM) are capable of acquiring images with better than 1nm resolution, and HIM images are particularly rich in morphological surface details. However, such images are generally quite noisy. A major challenge is to denoise these

Reconstructing the Past From Imprecise Knowledge of the Present: Some Examples of Non Uniqueness in Solving Parabolic Equations Backward in Time

April 13, 2011

Author(s)

Alfred S. Carasso

Bochner Subordination, Logarithmic Diffusion Equations, and Blind Deconvolution of Hubble Space Telescope Imagery and Other Scientific Data

November 30, 2010

Author(s)

Alfred S. Carasso

Generalized Linnik processes and associated logarithmic diffusion equations can be constructed by appropriate Bochner randomization of the time variable in Brownian motion and the related heat conduction equation. Remarkably, generalized Linnik

FRACTIONAL DIFFUSION, LOW EXPONENT LEVY STABLE LAWS, AND SLOW MOTION DENOISING OF HELIUM ION MICROSCOPE NANOSCALE IMAGERY

September 30, 2010

Author(s)

Alfred S. Carasso, Andras Vladar

Bochner Subordination, Logarithmic Diffusion Equations, and Blind Deconvolution of Hubble Space Telescope Imagery and Other Scientific Data

September 23, 2009

Author(s)

Alfred S. Carasso

False Characteristic Functions and Other Pathologies in Variational Blind Deconvolution. A Method of Recovery.

September 9, 2009

Author(s)

Alfred S. Carasso

Given a blurred image g(x, y), variational blind deconvolution seeks to reconstruct both the unknown blur k(x, y), and the unknown sharp image f(x, y), by minimizing an appropriate cost functional. This paper restricts attention to a rich and significant

Calibrating Image Roughness by Estimating Lipschitz Exponents, with Applications to Image Restoration

March 3, 2008

Author(s)

Alfred S. Carasso

Most commonly occurring images f(x,y) are not smoothly differentiable functions of the variables x and y. Rather, these images display edges, localized sharp features, and other significant fine scale details or texture. Correct characterization and

Calibrating Image Roughness by Estimating Lipschitz Exponents, with Applications to Image Restoration

August 1, 2007

Author(s)

Alfred S. Carasso, Andras Vladar

APEX Blind Deconvolution of Color Hubble Space Telescope Imagery and Other Astronomical Data

October 1, 2006

Author(s)

Alfred S. Carasso

The APEX method is a non-iterative, single frame, direct blind deconvolution technique that can sharpen certain kinds of high resolution images in quasi real-time. The method is predicated on a restricted class of blurs, in the form of 2D heavy-tailed bell

APEX Blind Deconvolution of Real Hubble Space Telescope Imagery and Other Astronomical Data

October 1, 2006

Author(s)

Alfred S. Carasso