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Comparing GPU Implementations of Bilateral and Anisotropic Diffusion Filters for 3D Biomedical Datasets

Description: We compare the performance of hand-tuned CUDA implementations of bilateral and anisotropic diffusion filters for denoising 3D MRI datasets. Our tests sweep comparable parameters for the two filters and measure total runtime, memory bandwidth, computational throughput, and mean squared errors relative to a noiseless reference dataset.
Date: May 6, 2010
Creator: Howison, Mark
Partner: UNT Libraries Government Documents Department

Modern Techniques in Acoustical Signal and Image Processing

Description: Acoustical signal processing problems can lead to some complex and intricate techniques to extract the desired information from noisy, sometimes inadequate, measurements. The challenge is to formulate a meaningful strategy that is aimed at performing the processing required even in the face of uncertainties. This strategy can be as simple as a transformation of the measured data to another domain for analysis or as complex as embedding a full-scale propagation model into the processor. The aims of both approaches are the same--to extract the desired information and reject the extraneous, that is, develop a signal processing scheme to achieve this goal. In this paper, we briefly discuss this underlying philosophy from a ''bottom-up'' approach enabling the problem to dictate the solution rather than visa-versa.
Date: April 4, 2002
Creator: Candy, J V
Partner: UNT Libraries Government Documents Department

Skin Detection in Image and Video

Description: Video from the Fall 2018 3 Minute Thesis (3MTĀ®) Final Competition. In this video, ABM Rezbaul Islam presents his research methods, findings, and its significance in non-technical language.
Date: November 17, 2018
Creator: Islam, A. B. M. Rezbaul
Partner: UNT College of Engineering

Synthesis of 2-D Images From the Wigner Distribution with Applications to Mammography and Edge Extraction

Description: A new method for the general application of quadratic spatial/spatial frequency domain filtering to imagery is presented in this dissertation. The major contribution of this research is the development of an original algorithm for approximating the inverse psuedo Wigner distribution through synthesis of an image in the spatial domain which approximates the result of filtering an original image in the DPWD domain.
Date: December 1995
Creator: Pettit, Elaine J. (Elaine Joyce)
Partner: UNT Libraries

Joint inversion of geophysical data for site characterization and restoration monitoring

Description: The purpose of this project is to develop a computer code for joint inversion of seismic and electrical data, to improve underground imaging for site characterization and remediation monitoring. The computer code developed in this project will invert geophysical data to obtain direct estimates of porosity and saturation underground, rather than inverting for seismic velocity and electrical resistivity or other geophysical properties. This is intended to be a significant improvement in the state-of-the-art of underground imaging, since interpretation of data collected at a contaminated site would become much less subjective. Potential users include DOE scientists and engineers responsible for characterizing contaminated sites and monitoring remediation of contaminated sites. In this three-year project, we use a multi-phase approach consisting of theoretical and numerical code development, laboratory investigations, testing on available laboratory and borehole geophysics data sets, and a controlled field experiment, to develop practical tools for joint electrical and seismic data interpretation.
Date: May 28, 1998
Creator: Berge, P. A.
Partner: UNT Libraries Government Documents Department

Distributed video coding for arrays of remote sensing nodes : final report.

Description: This document is the final report for the Sandia National Laboratory funded Student Fellowship position at New Mexico State University (NMSU) from 2008 to 2010. Ivan Mecimore, the PhD student in Electrical Engineering at NMSU, was conducting research into image and video processing techniques to identify features and correlations within images without requiring the decoding of the data compression. Such an analysis technique would operate on the encoded bit stream, potentially saving considerable processing time when operating on a platform that has limited computational resources. Unfortunately, the student has elected in mid-year not to continue with his research or the fellowship position. The student is unavailable to provide any details of his research for inclusion in this final report. As such, this final report serves solely to document the information provided in the previous end of year summary.
Date: June 1, 2010
Creator: Mecimore, Ivan (New Mexico State University); Creusere, Chuck D. (New Mexico State University) & Merchant, Bion John
Partner: UNT Libraries Government Documents Department

Poblano v1.0 : a Matlab toolbox for gradient-based optimization.

Description: We present Poblano v1.0, a Matlab toolbox for solving gradient-based unconstrained optimization problems. Poblano implements three optimization methods (nonlinear conjugate gradients, limited-memory BFGS, and truncated Newton) that require only first order derivative information. In this paper, we describe the Poblano methods, provide numerous examples on how to use Poblano, and present results of Poblano used in solving problems from a standard test collection of unconstrained optimization problems.
Date: March 1, 2010
Creator: Dunlavy, Daniel M.; Acar, Evrim (Sandia National Laboratories, Livermore, CA) & Kolda, Tamara Gibson (Sandia National Laboratories, Livermore, CA)
Partner: UNT Libraries Government Documents Department

Sunfall: a collaborative visual analytics system for astrophysics

Description: Computational and experimental sciences produce and collect ever-larger and complex datasets, often in large-scale, multi-institution projects. The inability to gain insight into complex scientific phenomena using current software tools is a bottleneck facing virtually all endeavors of science. In this paper, we introduce Sunfall, a collaborative visual analytics system developed for the Nearby Supernova Factory, an international astrophysics experiment and the largest data volume supernova search currently in operation. Sunfall utilizes novel interactive visualization and analysis techniques to facilitate deeper scientific insight into complex, noisy, high-dimensional, high-volume, time-critical data. The system combines novel image processing algorithms, statistical analysis, and machine learning with highly interactive visual interfaces to enable collaborative, user-driven scientific exploration of supernova image and spectral data. Sunfall is currently in operation at the Nearby Supernova Factory; it is the first visual analytics system in production use at a major astrophysics project.
Date: July 7, 2008
Creator: Aragon, Cecilia R.; Aragon, Cecilia R.; Bailey, Stephen J.; Poon, Sarah; Runge, Karl & Thomas, Rollin C.
Partner: UNT Libraries Government Documents Department

Adaptive optics and phase diversity imaging for responsive space applications.

Description: The combination of phase diversity and adaptive optics offers great flexibility. Phase diverse images can be used to diagnose aberrations and then provide feedback control to the optics to correct the aberrations. Alternatively, phase diversity can be used to partially compensate for aberrations during post-detection image processing. The adaptive optic can produce simple defocus or more complex types of phase diversity. This report presents an analysis, based on numerical simulations, of the efficiency of different modes of phase diversity with respect to compensating for specific aberrations during post-processing. It also comments on the efficiency of post-processing versus direct aberration correction. The construction of a bench top optical system that uses a membrane mirror as an active optic is described. The results of characterization tests performed on the bench top optical system are presented. The work described in this report was conducted to explore the use of adaptive optics and phase diversity imaging for responsive space applications.
Date: November 1, 2004
Creator: Smith, Mark William & Wick, David Victor
Partner: UNT Libraries Government Documents Department

Quasar target selection fiber efficiency

Description: We present estimates of the efficiency for finding QSOs as a function of limiting magnitude and galactic latitude. From these estimates, we have formulated a target selection strategy that should net 80,000 QSOs in the north galactic cap with an average of 70 fibers per plate, not including fibers reserved for high-redshift quasars. With this plan, we expect 54% of the targets to be QSOs. The North Galactic Cap is divided into two zones of high and low stellar density. We use about five times as many fibers for QSO candidates in the half of the survey with the lower stellar density as we use in the half with higher stellar density. The current plan assigns 15% of the fibers to FIRST radio sources; if these are not available, those fibers would be allocated to lower probability QSO sources, dropping the total number of QSOs by a small factor (5%). We will find about 17,000 additional quasars in the southern strips, and maybe a few more at very high redshift. Use was made of two data sets: the star and quasar simulated test data generated by Don Schneider, and the data from UJFN plate surveys by Koo (1986) and Kron (1980). This data was compared to results from the Palomar-Green Survey and a recent survey by Pat Osmer and collaborators.
Date: May 1, 1996
Creator: Newberg, H. & Yanny, B.
Partner: UNT Libraries Government Documents Department

Shiva: An astronomical data analysis framework

Description: A key online and off-line software component of the Sloan Digital Sky Survey (SDSS) is Shiva. Shiva provides a readily extendible framework upon which the SDSS data reduction pipeline software is built. In this paper we present an introduction to the Shiva data analysis framework. We briefly discuss the features and the inherent prototyping and rapid development capabilities that make Shiva an integral part in the on-going development of SDSS software.
Date: December 1, 1995
Creator: Sergey, G.; Berman, E.; Huang, C.H.; Kent, S.; Newberg, H; Nicinski, T. et al.
Partner: UNT Libraries Government Documents Department

Superresolution and Synthetic Aperture Radar

Description: Superresolution concepts offer the potential of resolution beyond the classical limit. This great promise has not generally been realized. In this study we investigate the potential application of superresolution concepts to synthetic aperture radar. The analytical basis for superresolution theory is discussed. The application of the concept to synthetic aperture radar is investigated as an operator inversion problem. Generally, the operator inversion problem is ill posed. A criterion for judging superresolution processing of an image is presented.
Date: May 1, 2001
Partner: UNT Libraries Government Documents Department

Stereoscopic Height Estimation from Multiple Aspect Synthetic Aperture Radar Images

Description: A Synthetic Aperture Radar (SAR) image is a two-dimensional projection of the radar reflectivity from a 3-dimensional object or scene. Stereoscopic SAR employs two SAR images from distinct flight paths that can be processed together to extract information of the third collapsed dimension (typically height) with some degree of accuracy. However, more than two SAR images of the same scene can similarly be processed to further improve height accuracy, and hence 3-dimensional position accuracy. This report shows how.
Date: August 1, 2001
Partner: UNT Libraries Government Documents Department

San Juan Fracture Characterization Project: Status and current results

Description: The overall objectives of this report are to extend current state-of-the-art 3-D imaging to extract the optimal information for fracture quantification and to develop next generation capability in fracture imaging for true 3-D imaging of the static and dynamic fracture properties.
Date: February 26, 2001
Creator: Majer, E.L.; Daley, T.M.; Myer, L.R.; Nihei, K.; Queen, J.; Sinton, J. et al.
Partner: UNT Libraries Government Documents Department

Detection of linear features using a localized radon transform with a wavelet filter

Description: One problem of interest to the oceanic engineering community is the detection and enhancement of internal wakes in open water synthetic aperture radar (SAR) images. Internal wakes, which occur when a ship travels in a stratified medium, have a V shape extending from the ship, and a chirp-like feature across each arm. The Radon transform has been applied to the detection and the enhancement problems in internal wake images to account for the linear features while the wavelet transform has been applied to the enhancement problem in internal wake images to account for the chirp-like features. In this paper, a new transform, a localized Radon transform with a wavelet filter (LRTWF), is developed which accounts for both the linear and the chirp-like features of the internal wake. This transform is then incorporated into optimal and sub-optimal detection schemes for images (with these features) which are contaminated by additive Gaussian noise.
Date: December 13, 1999
Creator: Warrick, A L & Delaney, P A
Partner: UNT Libraries Government Documents Department