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Full-Text Articles in Physical Sciences and Mathematics

Matrix Multiplication, Trilinear Decompositions, Apa Algorithms, And Summation, Victor Pan Jan 2016

Matrix Multiplication, Trilinear Decompositions, Apa Algorithms, And Summation, Victor Pan

Faculty Works

Matrix multiplication (hereafter we use the acronym MM) is among the most fundamental operations of modern computations. The efficiency of its performance depends on various factors, in particular vectorization, data movement and arithmetic complexity of the computations, but here we focus just on the study of the arithmetic cost and the impact of this study on other areas of modern computing. In the early 1970s it was expected that the straightforward cubic time algorithm for MM will soon be accelerated to enable MM in nearly quadratic arithmetic time, with some far fetched implications. While pursuing this goal the mainstream research ...


Pre-Breakdown Arcing As A Proxy For Dc Dielectric Breakdown Testing Of Polymeric Insulators, Jr Dennison, Allen Andersen Oct 2015

Pre-Breakdown Arcing As A Proxy For Dc Dielectric Breakdown Testing Of Polymeric Insulators, Jr Dennison, Allen Andersen

Presentations

No abstract provided.


Mixed Weibull Distribution Model Of Dc Dielectric Breakdowns With Dual Defect Modes, Allen Andersen, Jr Dennison Oct 2015

Mixed Weibull Distribution Model Of Dc Dielectric Breakdowns With Dual Defect Modes, Allen Andersen, Jr Dennison

Presentations

No abstract provided.


An Optimal Threshold Strategy In The Two-Envelope Problem With Partial Information, Martin Egozcue, Luis Fuentes García Oct 2015

An Optimal Threshold Strategy In The Two-Envelope Problem With Partial Information, Martin Egozcue, Luis Fuentes García

Martin Egozcue

No abstract provided.


Small Satellite Verification And Assessment Test Facility With Space Environments Effects Ground-Testing Capabilities, Eric Stromberg, Crystal Frazier, Lisa Montierth Phillipps, Alex Souvall, Jr Dennison, James S. Dyer Aug 2015

Small Satellite Verification And Assessment Test Facility With Space Environments Effects Ground-Testing Capabilities, Eric Stromberg, Crystal Frazier, Lisa Montierth Phillipps, Alex Souvall, Jr Dennison, James S. Dyer

Presentations

The Utah State University Space Dynamics Laboratory (SDL) and Materials Physics Group (MPG) have developed an extensive versatile and cost-effective pre-launch test capability for verification and assessment of small satellites, system components, and spacecraft materials. The facilities can perform environmental testing, component characterization, system level hardware in-the-loop testing, and qualification testing to ensure that each element is functional, reliable, and working per its design. Unique capabilities of SDL’s Nano-Satellite Operation Verification and Assessment (NOVA) test facility include: (i) mass and moment of inertia testing using a high resolution mass measurement table to determine the center of gravity and an ...


Gait Transition Dynamics Are Modulated By Experimental Protocol, Mohammad Abdolvahab, Jason Gordon Jul 2015

Gait Transition Dynamics Are Modulated By Experimental Protocol, Mohammad Abdolvahab, Jason Gordon

Mohammad Abdolvahab

No abstract provided.


Rotation Lightcurves Of Small Jovian Trojan Asteroids, Linda French, Robert D. Stephens, Daniel Coley, Lawrence H. Wasserman, Jennifer Sieben Jul 2015

Rotation Lightcurves Of Small Jovian Trojan Asteroids, Linda French, Robert D. Stephens, Daniel Coley, Lawrence H. Wasserman, Jennifer Sieben

Linda French

Several lines of evidence support a common origin for, and possible hereditary link between, cometary nuclei and Jovian Trojan asteroids. Due to their distance and low albedos, few comet-sized Trojans have been studied. We present new lightcurve information for 19 Trojans ≲ 30 km in diameter, more than doubling the number of objects in this size range for which some rotation information is known. The minimum densities for objects with complete lightcurves are estimated and are found to be comparable to those measured for cometary nuclei. A significant fraction (~40%) of this observed small Trojan population rotates slowly (P > 24 hours ...


Influence Of Thermal Treatment On Electrical And Physical Properties Of Coated Ceramics, K. Guerch, T. Paulmier, Justin Dekany, Jr Dennison, S. Guillemet-Fritsch, P. Lenormand Jun 2015

Influence Of Thermal Treatment On Electrical And Physical Properties Of Coated Ceramics, K. Guerch, T. Paulmier, Justin Dekany, Jr Dennison, S. Guillemet-Fritsch, P. Lenormand

Presentations

Technical dielectric materials and ceramics are used in many different high technology industrial areas and especially for spacecraft applications. On satellites, these materials are subjected to extreme conditions due to the space plasma environment. To survive, these ceramic insulators must have exceptional electrical and thermal properties. Boron Nitride (BN) and Aluminum Oxide (Al 2O3) are used in particular because they combine good electrical insulation and high thermal conductivity. However, BN and Al2O3 used in spacecraft interiors are exposed to critical radiation demands, where these insulators are irradiated by electrons with high energies and flux. Charged particles are trapped in the ...


Agenda: Innovations In Managing Western Water: New Approaches For Balancing Environmental, Social, And Economic Outcomes, University Of Colorado Boulder. Getches Wilkinson Center For Natural Resources, Energy, And The Environment Jun 2015

Agenda: Innovations In Managing Western Water: New Approaches For Balancing Environmental, Social, And Economic Outcomes, University Of Colorado Boulder. Getches Wilkinson Center For Natural Resources, Energy, And The Environment

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Many aspects of western water allocation and management are the product of independent and uncoordinated actions, several occurring a century or more ago. However, in this modern era of water scarcity, it is increasingly acknowledged that more coordinated and deliberate decision-making is necessary for effectively balancing environmental, social, and economic objectives. In recent years, a variety of forums, processes, and tools have emerged to better manage the connections between regions, sectors, and publics linked by shared water systems. In this event, we explore the cutting edge efforts, the latest points of contention, and the opportunities for further progress.


Castelnuovo–Mumford Regularity And Arithmetic Cohen–Macaulayness Of Complete Bipartite Subspace Arrangements, Zach Teitler, Douglas A. Torrence Jun 2015

Castelnuovo–Mumford Regularity And Arithmetic Cohen–Macaulayness Of Complete Bipartite Subspace Arrangements, Zach Teitler, Douglas A. Torrence

Mathematics Faculty Publications and Presentations

We give the Castelnuovo–Mumford regularity of arrangements of (n−2)-planes in Pn whose incidence graph is a sufficiently large complete bipartite graph, and determine when such arrangements are arithmetically Cohen–Macaulay.


The Consequences Of Plan Colombia: Domestic Drug Policies In Colombia, Brittany T. Reid May 2015

The Consequences Of Plan Colombia: Domestic Drug Policies In Colombia, Brittany T. Reid

Environmental Studies Theses

None


Reconstruction Of The Post-Glacial Formation Of The Peddocks Island Salt Marsh, Hull, Ma, Sean W. Enos May 2015

Reconstruction Of The Post-Glacial Formation Of The Peddocks Island Salt Marsh, Hull, Ma, Sean W. Enos

Geology Theses

Climate change and associated sea level rise are of a large concern, and studying the environment’s history will allow for better predictions on the future. Salt marshes provide an excellent site for the study of changes that have occurred, as they accrete at a rate synonymous to sea level rise. Tidal salt marshes accrete upwards and landwards as diurnal tides flood the marsh, bringing in sediment. Major storm events also are known to provide sediment for marsh accretion. Lower rates of sea level rise allow marsh plants to keep in pace with incoming sediments (Niering and Warren, 1980). Sediment ...


Mobilization Of Metals By Fungi In Historic Cemeteries, Eleanor D. Briggs May 2015

Mobilization Of Metals By Fungi In Historic Cemeteries, Eleanor D. Briggs

Geology Theses

Interactions among fungi, soil, and metals are at the heart of nutrient cycling in terrestrial systems. Both major and trace elements are found in soils, but the degree to which they are biologically available is influenced by chemical weathering of soil minerals by fungi. In addition to contributing to weathering, mushrooms are known to bioaccumulate metals from soil, so edible mushrooms growing on soils contaminated with toxic metals can cause harm to those who eat them. This study focuses on metal content of mushrooms and soils from cemeteries that are suspected to be contaminated with arsenic as a result of ...


Paleoclimatic Implication Of Lake Sediment Geochemistry In Linnévatnet, Spitsbergen, Svalbard, Benjamin Gray Merkert May 2015

Paleoclimatic Implication Of Lake Sediment Geochemistry In Linnévatnet, Spitsbergen, Svalbard, Benjamin Gray Merkert

Geology Theses

Linnévatnet (Norwegian, Lake Linné) is a proglacial lake located on the archipelago Svalbard at approximately 78 degrees north latitude. In addition to the sediment released by Linnébreen (Norwegian, Linné Glacier), various small streams and solifluction lobes around the lake contribute to the total sediment input. In this study, two lake cores were taken from one location along with six bulk sediment samples from major sediment sources around the lake. The elemental chemistry and physical parameters of all samples were obtained using X-ray fluorescence and a Geotek MSCL, respectively, at Hartshorne Quaternary Lab at the University of Massachusetts Amherst. The mineralogy ...


Analysis And Comparison Of Physical Properties And Morphology Of Impact Melt Flows On Venus And The Moon To Determine Atmospheric Controls, Christine Elizabeth Dong May 2015

Analysis And Comparison Of Physical Properties And Morphology Of Impact Melt Flows On Venus And The Moon To Determine Atmospheric Controls, Christine Elizabeth Dong

Geology Theses

Impact melt flows form when target material melted by an impact breaches the rim of the impact crater. The melt flows out and away from the crater, forming a lava flow. Such flows have been identified on Venus and the Moon by previous studies. This study aims to document impact melt flows on these two bodies to determine the differences, if any, between them, and to ascertain whether these differences are due to atmospheric conditions. Previously recorded morphological data from Robert Herrick of the Lunar and Planetary Institute and Neish et al. (2014) are used in conjunction with S-band (12 ...


Image Segmentation Using Fuzzy-Spatial Taxon Cut, Lauren Barghout May 2015

Image Segmentation Using Fuzzy-Spatial Taxon Cut, Lauren Barghout

MODVIS Workshop

Images convey multiple meanings that depend on the context in which the viewer perceptually organizes the scene. This presents a problem for automated image segmentation, because it adds uncertainty to the process of selecting which objects to include or not include within a segment. I’ll discuss the implementation of a fuzzy-logic-natural-vision-processing engine that solves this problem by assuming the scene architecture prior to processing. The scene architecture, a standardized natural-scene-perception-taxonomy comprised of a hierarchy of nested spatial-taxons. Spatial-taxons are regions (pixel-sets) that are figure-like, in that they are perceived as having a contour, are either `thing-like', or a `group ...


Video Event Understanding With Pattern Theory, Fillipe Souza, Sudeep Sarkar, Anuj Srivastava, Jingyong Su May 2015

Video Event Understanding With Pattern Theory, Fillipe Souza, Sudeep Sarkar, Anuj Srivastava, Jingyong Su

MODVIS Workshop

We propose a combinatorial approach built on Grenander’s pattern theory to generate semantic interpretations of video events of human activities. The basic units of representations, termed generators, are linked with each other using pairwise connections, termed bonds, that satisfy predefined relations. Different generators are specified for different levels, from (image) features at the bottom level to (human) actions at the highest, providing a rich representation of items in a scene. The resulting configurations of connected generators provide scene interpretations; the inference goal is to parse given video data and generate high-probability configurations. The probabilistic structures are imposed using energies ...


The Psychophysics Of Metacognition And Meta D', S A. Klein May 2015

The Psychophysics Of Metacognition And Meta D', S A. Klein

MODVIS Workshop

In the past five years there has been a surge of renewed interest in metacognition and meta d'. It is a very interesting and highly controversial area of research. It is interesting because thinking about subjective experiences provides new insight into decision making. The new book on the topic edited by Fleming and Frith, and the Matiscalco article in that book provide an excellent summary of the issues. My view is that double judgment signal detection theory, plus new approaches for multinomial modeling can provide important insights into the recent meta d' findings. I will show how improved rating scale ...


Two Correspondence Problems Easier Than One, Aaron Michaux, Zygmunt Pizlo May 2015

Two Correspondence Problems Easier Than One, Aaron Michaux, Zygmunt Pizlo

MODVIS Workshop

Computer vision research rarely makes use of symmetry in stereo reconstruction despite its established importance in perceptual psychology. Such stereo reconstructions produce visually satisfying figures with precisely located points and lines, even when input images have low or moderate resolution. However, because few invariants exist, there are no known general approaches to solving symmetry correspondence on real images. The problem is significantly easier when combined with the binocular correspondence problem, because each correspondence problem provides strong non-overlapping constraints on the solution space. We demonstrate a system that leverages these constraints to produce accurate stereo models from pairs of binocular images ...


Binocular 3d Motion Perception As Bayesian Inference, Martin Lages, Suzanne Heron May 2015

Binocular 3d Motion Perception As Bayesian Inference, Martin Lages, Suzanne Heron

MODVIS Workshop

The human visual system encodes monocular motion and binocular disparity input before it is integrated into a single 3D percept. Here we propose a geometric-statistical model of human 3D motion perception that solves the aperture problem in 3D by assuming that (i) velocity constraints arise from inverse projection of local 2D velocity constraints in a binocular viewing geometry, (ii) noise from monocular motion and binocular disparity processing is independent, and (iii) slower motions are more likely to occur than faster ones. In two experiments we found that instantiation of this Bayesian model can explain perceived 3D line motion direction under ...


Formal Aspects Of Non-Rigid-Shape-From-Motion Perception, Vicky Froyen, Qasim Zaidi May 2015

Formal Aspects Of Non-Rigid-Shape-From-Motion Perception, Vicky Froyen, Qasim Zaidi

MODVIS Workshop

Our world is full of objects that deform over time, for example animals, trees and clouds. Yet, the human visual system seems to readily disentangle object motions from non-rigid deformations, in order to categorize objects, recognize the nature of actions such as running or jumping, and even to infer intentions. A large body of experimental work has been devoted to extracting rigid structure from motion, but there is little experimental work on the perception of non-rigid 3-D shapes from motion (e.g. Jain, 2011). Similarly, until recently, almost all formal work had concentrated on the rigid case. In the last ...


Object Recognition And Visual Search With A Physiologically Grounded Model Of Visual Attention, Frederik Beuth, Fred H. Hamker May 2015

Object Recognition And Visual Search With A Physiologically Grounded Model Of Visual Attention, Frederik Beuth, Fred H. Hamker

MODVIS Workshop

Visual attention models can explain a rich set of physiological data (Reynolds & Heeger, 2009, Neuron), but can rarely link these findings to real-world tasks. Here, we would like to narrow this gap with a novel, physiologically grounded model of visual attention by demonstrating its objects recognition abilities in noisy scenes.

To base the model on physiological data, we used a recently developed microcircuit model of visual attention (Beuth & Hamker, in revision, Vision Res) which explains a large set of attention experiments, e.g. biased competition, modulation of contrast response functions, tuning curves, and surround suppression. Objects are represented by object-view specific neurons, learned via a trace learning approach (Antonelli et al., 2014, IEEE TAMD). A visual cortex model combines the microcircuit with neuroanatomical properties like top-down attentional processing, hierarchical-increasing receptive field sizes, and synaptic transmission delays. The visual cortex model is complemented by a model of the frontal eye field (Zirnsak et al., 2011, Eur J Neurosci).

We evaluated the model on a realistic object recognition task in which a given target has to be localized in a scene (guided visual search task), using 100 different target objects, 1000 scenes, and two backgrounds. The model achieves an accuracy of 92% at black, and of 71% at white-noise backgrounds. We found that two of the underlying, neuronal attention mechanisms are prominently relevant for guided visual search: amplification of neurons preferring the target; and suppression of neurons encoding distractors or background noise.


Modeling Visual Features To Recognize Biological Motion: A Developmental Approach, Giulio Sandini, Nicoletta Noceti, Alessandra Sciutti, Francesco Rea, Alessandro Verri, Francesca Odone May 2015

Modeling Visual Features To Recognize Biological Motion: A Developmental Approach, Giulio Sandini, Nicoletta Noceti, Alessandra Sciutti, Francesco Rea, Alessandro Verri, Francesca Odone

MODVIS Workshop

In this work we deal with the problem of designing and developing computational vision models – comparable to the early stages of the human development – using coarse low-level information.

More specifically, we consider a binary classification setting to characterize biological movements with respect to non-biological dynamic events. To this purpose, our model builds on top of the optical flow estimation, and abstract the representation to simulate the limited amount of visual information available at birth. We take inspiration from known biological motion regularities explained by the Two-Thirds Power Law, and design a motion representation that includes different low-level features, which can ...


A Study On Photodegradation And The Fate Of Pyrogenic Carbon, John T. Howell May 2015

A Study On Photodegradation And The Fate Of Pyrogenic Carbon, John T. Howell

Master's Theses

Accounting for all possible sources of atmospheric CO2 is a pressing issue today due to the increasing effects of climate change. Estimates suggested that on the order of 1.3 million tons of dissolved pyrogenic carbon (pyDOC) could be entering the northern Gulf of Mexico annually. Assessing the fate of pyDOC in aquatic systems is crucial to understanding ecosystem impacts and potential feedback to climate change. Current research indicates that despite a generally lower susceptibility to biodegradation than their unpyrolyzed equivalents, pyrogenic carbon is not environmentally inert. While the role of microorganisms on the fate and transformation ...


Mechanochemical Investigation Of A Glassy Epoxy-Amine Thermoset Subjected To Fatigue, Stephen F. Foster Mr. May 2015

Mechanochemical Investigation Of A Glassy Epoxy-Amine Thermoset Subjected To Fatigue, Stephen F. Foster Mr.

Dissertations

Covalent bonds in organic molecules can be produced, altered, and broken through various sources of energy and processes. These include photochemical, thermochemical, chemical, and mechanochemical processes. Polymeric materials derive their physical properties from the time scale of motion, summation of intermolecular forces, and number of chain entanglements and crosslinks. Glassy thermoset polymers experience mechanical fatigue during dynamic stress loading and properties diminish with inevitable material failure at stress levels below the ultimate tensile strength (UTS). Damage modeling has been successful in predicting the number of cycles required to induce failure in a specimen due to stress. However, it does not ...


Gal: A Stepwise Model For Automated Cloud Shadow Detection In Hico Oceanic Imagery Utilizing Guided Filter, Pixel Assignment, And Geometric Linking, Jennerpher Renee Meyers May 2015

Gal: A Stepwise Model For Automated Cloud Shadow Detection In Hico Oceanic Imagery Utilizing Guided Filter, Pixel Assignment, And Geometric Linking, Jennerpher Renee Meyers

Dissertations

Detection of cloud shadow pixels is an important step in image processing in several remote sensing ocean-color application domains, such as obtaining chlorophyll content. While shadow detection algorithms do exist, the vast majority are for over land which leaves few options for detection over water.

The detection of cloud shadow over water in HICO imagery is a unique problem. As its name implies, HICO (Hyperspectral Imager for the Coastal Ocean) imagery is produced for coastal and oceanic regions. Since land based algorithms remove water before processing, these approaches would not be applicable. The only currently published HICO shadow pixel detection ...


Secure And Reliabe Routing Protocol For Transmission Data In Wireless Sensor Mesh Networks, Nooh Adel Bany Muhammad May 2015

Secure And Reliabe Routing Protocol For Transmission Data In Wireless Sensor Mesh Networks, Nooh Adel Bany Muhammad

Dissertations

Abstract

Sensor nodes collect data from the physical world then exchange it until it reaches the intended destination. This information can be sensitive, such as battlefield surveillance. Therefore, providing secure and continuous data transmissions among sensor nodes in wireless network environments is crucial. Wireless sensor networks (WSN) have limited resources, limited computation capabilities, and the exchange of data through the air and deployment in accessible areas makes the energy, security, and routing major concerns in WSN. In this research we are looking at security issues for the above reasons. WSN is susceptible to malicious activities such as hacking and physical ...


Magnetoresistance Characteristics In Individual Fe3O4 Single Crystal Nanowire, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna May 2015

Magnetoresistance Characteristics In Individual Fe3O4 Single Crystal Nanowire, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna

Physics Faculty Publications and Presentations

We report on the magnetoresistance (MR) and electron transport measurements observed on asingle crystal magnetite nanowire prepared using a hydrothermal synthesis method. High-resolution electron microscopy revealed the single crystal magnetite nanowires with 80–120 nm thickness and up to 8 μm in length. Magnetic measurements showed the typical Verwey transition around 120 K with a 100 Oe room temperature coercivity and 45 emu/g saturationmagnetization, which are comparable to bulk magnetite. Electrical resistance measurements in 5-300 K temperature range were performed by scanning gate voltage and varying appliedmagnetic field. Electrical resistivity of the nanowire was found to be around ...


Heterojunction Metal-Oxide-Metal Au-Fe3O4-Au Single Nanowire Device For Spintronics, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna May 2015

Heterojunction Metal-Oxide-Metal Au-Fe3O4-Au Single Nanowire Device For Spintronics, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna

Physics Faculty Publications and Presentations

In this report, we present the synthesis of heterojunction magnetite nanowires in alumina template and describe magnetic and electrical properties from a single nanowire device for spintronics applications. Heterojunction Au-Fe-Au nanowire arrays were electrodeposited in porous aluminum oxide templates, and an extensive and controlled heat treatment process converted Fe segment to nanocrystalline cubic magnetite phase with well-defined Au-Fe3O4 interfaces as confirmed by the transmission electron microscopy. Magnetic measurements revealed Verwey transition shoulder around 120 K and a room temperature coercive field of 90 Oe. Current–voltage (I-V) characteristics of a single Au-Fe3O4-Au nanowire ...


Video Event Recognition And Prediction Based On Temporal Structure Analysis, Kang Li May 2015

Video Event Recognition And Prediction Based On Temporal Structure Analysis, Kang Li

Computer Engineering Dissertations

The increasing ubiquitousness of multimedia information in today's world has positioned video as a favored information vehicle, and given rise to an astonishing generation of social media and surveillance footage. Consumer-grade video is becoming abundant on the Internet, and it is now easier than ever to download multimedia material of any kind and quality. This raises a series of technological demands for automatic video understanding, which has motivated the research community to guide its steps towards a better attainment of such capabilities. As a result, current trends on cognitive vision promise to recognize complex events and self-adapt to different ...