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Recursive Non-Local Means Filter For Video Denoising, Redha A. Ali, Russell C. Hardie 2017 University of Dayton

Recursive Non-Local Means Filter For Video Denoising, Redha A. Ali, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

In this paper, we propose a computationally efficient algorithm for video denoising that exploits temporal and spatial redundancy. The proposed method is based on non-local means (NLM). NLM methods have been applied successfully in various image denoising applications. In the single-frame NLM method, each output pixel is formed as a weighted sum of the center pixels of neighboring patches, within a given search window.

The weights are based on the patch intensity vector distances. The process requires computing vector distances for all of the patches in the search window. Direct extension of this method from 2D to 3D, for video ...


Climate Change, Development, And The Global Commons, Robert J. Brecha 2017 University of Dayton

Climate Change, Development, And The Global Commons, Robert J. Brecha

The Social Practice of Human Rights: Charting the Frontiers of Research and Advocacy

An important link between energy, climate change, human development, and human rights comes in the form of a question that has yet to be answered satisfactorily: The earth’s atmosphere and other physical systems are the ultimate example of the global commons. Do future generations have a human right to an unchanged earth system? Sustainable Development Goals 13, 14, and 15 imply an affirmative answer. Given that climate scientists have a good estimate of the amount of carbon dioxide that can be emitted before the safe uptake capacity of the atmosphere is breached, how do we allocate that remaining atmospheric ...


Discrete Space-Time Model For Heat Conduction: Application To Sizedependent Thermal Conductivity In Nano-Films, Sergey Sobolev 2017 Institute of problems of Chemical Physics, Russia

Discrete Space-Time Model For Heat Conduction: Application To Sizedependent Thermal Conductivity In Nano-Films, Sergey Sobolev

Sergey Sobolev

No abstract provided.


Characterizing The Effects Of Radiation On Muscle Cells, Lori Caldwell, Elizabeth Vargis, Charles Harding, JR Dennison 2017 Utah State University

Characterizing The Effects Of Radiation On Muscle Cells, Lori Caldwell, Elizabeth Vargis, Charles Harding, Jr Dennison

Posters

One of the primary concerns for those spending time in low gravity and high radiation environments is muscle atrophy. A major cause of muscular atrophy is oxidative stress which is amplified by increased levels of ionizing radiation during spaceflight. Additionally, high levels of radiation can damage DNA, increasing the risk of cancer. Utah State University’s Space Environment Test Facility was used to irradiate C2C12 myoblasts and human vascular endothelial cells with a beta-radiation dosage mimicking that on the International Space Station and a 3-year deep space mission.


An Enhanced Operational Definition Of Dielectric Breakdown For Dc Voltage Step-Up Tests, Allen Andersen, JR Dennison 2017 Utah State University

An Enhanced Operational Definition Of Dielectric Breakdown For Dc Voltage Step-Up Tests, Allen Andersen, Jr Dennison

Allen Andersen

The imprecise definition of breakdown in the ASTM D3755-14 standard can misidentify breakdown. If the recommended test circuit current sensing element threshold is set too high, breakdown may occur undetected. Conversely, false positives may result from designating a low current threshold. An operational definition of breakdown much less sensitive to these pitfalls is outlined herein. This enhanced definition of breakdown is based on the average rate of change of the leakage current with increasing voltage, rather than a simple current threshold, avoiding ambiguous association with anomalies in current traces. For tests that continuously monitor leakage current, breakdown can be detected ...


Dependence Of Electrostatic Field Strength On Voltage Ramp Rate For Spacecraft Materials, Krysta Moser, Allen Andersen, JR Dennison 2017 Utah State University

Dependence Of Electrostatic Field Strength On Voltage Ramp Rate For Spacecraft Materials, Krysta Moser, Allen Andersen, Jr Dennison

Allen Andersen

This work investigated the dependence of electrostatic field strength for spacecraft materials on voltage ramp rate, by applying an increasing incremental electrostatic field until electrostatic breakdown occurred. Tests on Kapton E found that at ramp rates two or three orders of magnitude lower than the maximum recommended rate, the electrostatic breakdown field, FESD was lower by a factor of two or more. This suggests that tabulated values of FESD, which have been used by the spacecraft charging community, could substantially overestimate FESD in common slowly evolving spacecraft situations. This study expanded these ramp rate tests to include a wider range ...


Perspectives On The Distributions Of Esd Breakdowns For Spacecraft Charging Applications, Allen Andersen, Krysta Moser, JR Dennison 2017 Utah State University

Perspectives On The Distributions Of Esd Breakdowns For Spacecraft Charging Applications, Allen Andersen, Krysta Moser, Jr Dennison

Allen Andersen

Electrostatic discharge (ESD) continues to pose significant risks to space missions despite decades of intense study. Tabulated values of material breakdown strength used in spacecraft charging models are often based on cursory measurements that may not be fully relevant to a given mission. Materials physics offers insight into the pertinent variables that affect breakdown and how to address them experimentally for spacecraft applications. We present measured distributions of ESD data across several test configurations for three polymeric materials that, taken together, begin to provide an understanding of how to estimate the likelihood of ESD events over a spacecraft’s mission ...


Temperature Dependence Of Electrostatic Discharge In Highly Disordered Insulating Polymers, Tyler Kippen, Allen Andersen, JR Dennison 2017 Utah State University

Temperature Dependence Of Electrostatic Discharge In Highly Disordered Insulating Polymers, Tyler Kippen, Allen Andersen, Jr Dennison

Allen Andersen

No abstract provided.


Temperature Dependency Of Electrostatic Breakdown In Ldpe And Peek, Tyler Kippen, Allen Andersen, JR Dennison 2017 Utah State University

Temperature Dependency Of Electrostatic Breakdown In Ldpe And Peek, Tyler Kippen, Allen Andersen, Jr Dennison

Allen Andersen

Electrostatic breakdown is a leading cause of many of the anomalies and failures attributed to spacecraft interactions with the space environment. It is therefore critical to understand how the electrostatic field strength varies due to changing environmental conditions, including temperature and radiation dose. Standard step-up to electrostatic discharge (ESD) tests were performed on two polymers, low density polyethylene (LDPE) and polyetheretherketone (PEEK). Tests were done at room temperature and at other temperatures ranging from ~130 K to ~350 K. Preliminary analysis found that samples tested at a higher temperature had lower average breakdown field strength and a narrower distribution of ...


Dependence Of Electrostatic Field Strength On Voltage Ramp Rate For Spacecraft Materials, Krysta Moser, Allen Andersen, JR Dennison 2017 Utah State University

Dependence Of Electrostatic Field Strength On Voltage Ramp Rate For Spacecraft Materials, Krysta Moser, Allen Andersen, Jr Dennison

Allen Andersen

No abstract provided.


Highly Accelerated Test Method For Characterizing Likelihood Of Breakdown In Hvdc Dielectric Materials, Allen Andersen, JR Dennison 2017 Utah State University

Highly Accelerated Test Method For Characterizing Likelihood Of Breakdown In Hvdc Dielectric Materials, Allen Andersen, Jr Dennison

Allen Andersen

Increasing application and development of HVDC technologies emphasizes the need for improved characterization of candidate insulating materials. Accurately predicting the lifetime to breakdown of dielectric materials by means of accelerated voltage step-up to breakdown tests can be prohibitively time consuming. Step-up to breakdown tests with sufficiently slow voltage ramp rates that continuously monitor leakage current have detected a distribution of DC partial discharge (DCPD) events occurring prior to breakdown, which increase with increasing field. These DCPD distributions are shown to correlate strongly with the likelihood of breakdown for four common polymers. Given that hundreds of DCPD events are typically observed ...


Electron Yield Of A Carbon-Composite Nanodielectric, Matthew Robertson, Justin Christensen, Greg Wilson, JR Dennison 2017 Utah State University

Electron Yield Of A Carbon-Composite Nanodielectric, Matthew Robertson, Justin Christensen, Greg Wilson, Jr Dennison

Posters

No abstract provided.


Imaging Electronic Motions By Ultrafast Electron Diraction, Hua-Chieh Shao, Anthony F. Starace 2017 University of Nebraska-Lincoln

Imaging Electronic Motions By Ultrafast Electron Diraction, Hua-Chieh Shao, Anthony F. Starace

Anthony F. Starace Publications

Recently ultrafast electron diraction and microscopy have reached unprecedented temporal resolution, and transient structures with atomic precision have been observed in various reactions. It is anticipated that these extraordinary advances will soon allow direct observation of electronic motions during chemical reactions. We therefore performed a series of theoretical investigations and simulations to investigate the imaging of electronic motions in atoms and molecules by ultrafast electron diraction. Three prototypical electronic motions were considered for hydrogen atoms. For the case of a breathing mode, the electron density expands and contracts periodically, and we show that the time-resolved scattering intensities re ect such ...


Energy-Resolved Coherent Diffraction From Laser-Driven Electronic Motion In Atoms, Hua-Chieh Shao, Anthony F. Starace 2017 University of Nebraska-Lincoln

Energy-Resolved Coherent Diffraction From Laser-Driven Electronic Motion In Atoms, Hua-Chieh Shao, Anthony F. Starace

Anthony F. Starace Publications

We investigate theoretically the use of energy-resolved ultrafast electron diffraction to image laser-driven electronic motion in atoms. A chirped laser pulse is used to transfer the valence electron of the lithium atom from the ground state to the first excited state. During this process, the electronic motion is imaged by 100-fs and 1-fs electron pulses in energy-resolved diffraction measurements. Simulations show that the angle-resolved spectra reveal the time evolution of the energy content and symmetry of the electronic state. The time-dependent diffraction patterns are further interpreted in terms of the momentum transfer. For the case of incident 1-fs electron pulses ...


Characterizing The Effects Of Radiation On Muscle Cells, Lori Caldwell, Charles Harding, JR Dennison, Elizabeth Vargis 2017 Utah State University

Characterizing The Effects Of Radiation On Muscle Cells, Lori Caldwell, Charles Harding, Jr Dennison, Elizabeth Vargis

Posters

As longer space missions become more desirable to public and private institutions, the physiological impact on astronauts must be considered. One of the primary concerns for those spending time in low gravity and high radiation environments is muscle atrophy. A major cause of muscular atrophy is oxidative stress which is amplified by increased levels of ionizing radiation during spaceflight. Additionally, high levels of radiation can damage DNA, increasing the risk of cancer. Utah State University’s Space Environment Test Facility was used to irradiate C2C12 myoblasts and human vascular endothelial cells with a dosage mimicking that on the International Space ...


Thermodynamics Of An Evolving Gene Sequence, Brian Clark 2017 Illinois State University

Thermodynamics Of An Evolving Gene Sequence, Brian Clark

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


The Behavior Response Of Antlion Larvae To Alternating Magnetic Fields, Lindsey Wagner, Caleb L. Adams 2017 Radford University

The Behavior Response Of Antlion Larvae To Alternating Magnetic Fields, Lindsey Wagner, Caleb L. Adams

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


A Critical Firing Rate In Synchronous Transitions Of Coupled Neurons, Annabelle Shaffer, Epaminondas Rosa, Rosangela Follmann 2017 Illinois State University

A Critical Firing Rate In Synchronous Transitions Of Coupled Neurons, Annabelle Shaffer, Epaminondas Rosa, Rosangela Follmann

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Mathematical Modeling Of Inhibitory Effects On Chemically Coupled Neurons, Nathhaniel Harraman, Epaminondas Rosa 2017 Illinois State University

Mathematical Modeling Of Inhibitory Effects On Chemically Coupled Neurons, Nathhaniel Harraman, Epaminondas Rosa

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Temperature Effects On Neuronal Tonic-To-Bursting Transitions, Manuela Burek, Epaminondas Rosa 2017 Illinois State University

Temperature Effects On Neuronal Tonic-To-Bursting Transitions, Manuela Burek, Epaminondas Rosa

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


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