Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 6 of 6

Full-Text Articles in Physical Sciences and Mathematics

Optical Flow At Occlusion Boundaries And In Occlusion Regions, Hua Meng Dec 2015

Optical Flow At Occlusion Boundaries And In Occlusion Regions, Hua Meng

Electronic Thesis and Dissertation Repository

Optical flow is an important research area in the Computer Vision field, with the estimation of optical flow at occlusion still an open problem. Traditional approaches to this problem have either used additional terms in a regularization calculation (the flow still tends to “bleed” across occlusion boundaries) or a local least squares calculation that attempted to minimize the influence of two adjacent differently moving regions on the optical flow at points close to both regions (the flow still tends to be “corrupted” by the two regions). Ideally, optical flow for two adjacent differently moving regions should be distinct right up …


Surface Reconstruction From Noisy And Sparse Data, Mark A. Brophy Dec 2015

Surface Reconstruction From Noisy And Sparse Data, Mark A. Brophy

Electronic Thesis and Dissertation Repository

We introduce a set of algorithms for registering, filtering and measuring the similarity of unorganized 3d point clouds, usually obtained from multiple views.

We contribute a method for computing the similarity between point clouds that represent closed surfaces, specifically segmented tumors from CT scans. We obtain watertight surfaces and utilize volumetric overlap to determine similarity in a volumetric way. This similarity measure is used to quantify treatment variability based on target volume segmentation both prior to and following radiotherapy planning stages.

We also contribute an algorithm for the drift-free registration of thin, non- rigid scans, where drift is the build-up …


Implementation Techniques For The Truncated Fourier Transform, Li Zhang Sep 2015

Implementation Techniques For The Truncated Fourier Transform, Li Zhang

Electronic Thesis and Dissertation Repository

We study various algorithms for the Truncated Fourier Transform (TFT) which is a variation of the Discrete Fourier Transform (DFT) that allows one to work with an input vector of arbitrary size without zero padding. After a review of the original algorithms for the forward and inverse TFT introduced by J. van der Hoeven, we consider the variation of D. Harvey as well as that of J. Johnson and L.C. Meng. Both variations are based on Cooley-Tukey like formulas. The former is called strict general radix as it strictly follows the specifications proposed by J. van der Hoeven, while the …


Generalized Inclusion-Exclusion, Mike W. Ghesquiere Aug 2015

Generalized Inclusion-Exclusion, Mike W. Ghesquiere

Electronic Thesis and Dissertation Repository

Sets are a foundational structure within mathematics and are commonly used as a building block for more complex structures. Just above this we have functions and sequences before an explosion of increasingly specialized structures. We propose a re-hanging of the tree with hybrid sets (that is, signed multi-sets), as well hybrid functions (functions with hybrid set domains) joining the ranks of sequences and functions. More than just an aesthetic change, this allows symbolic manipulation of structures in ways that might otherwise be cumbersome or inefficient. In particular, we will consider simplifying the product and sum of two piecewise functions or …


Using Cellular Automata And Lattice Boltzmann Methods To Model Cancer Growth: Analysis Of Combination Treatment Outcomes, Jenna L. Butler May 2015

Using Cellular Automata And Lattice Boltzmann Methods To Model Cancer Growth: Analysis Of Combination Treatment Outcomes, Jenna L. Butler

Electronic Thesis and Dissertation Repository

In Canada it is estimated that 76,600 people will die of cancer in 2014. Cancer, a collection of over 200 diseases, has differences existing between globally, between individuals and overtime in one individual. Treatment options are similarly varied. These differences make selecting the best possible treatment for every type of cancer very challenging. In addition, with no single cure for cancer, treatments are often combined in different ways to form the best overall option. In an attempt to synthesize the properties of these diseases into a collection of common cellular changes, Hanahan and Weinberg proposed ``the hallmarks of cancer" -- …


Geological Object Recognition In Extraterrestrial Environments, Gregory M. Elfers Apr 2015

Geological Object Recognition In Extraterrestrial Environments, Gregory M. Elfers

Electronic Thesis and Dissertation Repository

On July 4 1997, the landing of NASA’s Pathnder probe and its rover Sojourner marked the beginning of a new era in space exploration; robots with the ability to move have made up the vanguard of human extraterrestrial exploration ever since. With Sojourners landing, for the rst time, a ground traversing robot was at a distance too far from earth to make direct human control practical. This has given rise to the development of autonomous systems to improve the e?ciency of these robots,in both their ability to move,and their ability to make decisions regarding their environment. Computer Vision comprises a …