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Full-Text Articles in Physical Sciences and Mathematics

Learning From Disorder And Noise In Physical Biology, Taylor Emil Firman Jan 2018

Learning From Disorder And Noise In Physical Biology, Taylor Emil Firman

Electronic Theses and Dissertations

Stochasticity, disorder, and noise play crucial roles in the functioning of many biological systems over many different length scales. On the molecular scale, most proteins are envisioned as pristinely folded structures, but intrinsically disordered proteins (IDPs) have no such folded state and still serve distinct purposes within the cell. At the scale of gene regulation, realistic in vivo conditions produce stochastic fluctuations in gene expression that can lead to advantageous bet-hedging strategies, but can be difficult to characterize using a deterministic framework. Even at the organismal scale, germband extension (GBE) in Drosophila melanogaster embryos systematically elongates the epithelial tissue using …


Motivations, Team Dynamics, Development Practices And How They Impact The Success Of Open Source Software: A Study Of Projects Of Code For America Brigades, Le Chang Jan 2018

Motivations, Team Dynamics, Development Practices And How They Impact The Success Of Open Source Software: A Study Of Projects Of Code For America Brigades, Le Chang

Electronic Theses and Dissertations

Open data movement has nurtured the growth of civic open source software (OSS) in the recent decade. This emerging phenomenon has demonstrated a way that a community can collectively utilize technology to solve its problems.

This study is based on software projects in brigades of Code for America, which is a network of organizations that group volunteers to create digital solutions to community problems. In this study, we analyze the software engineering practices of current civic open source software development, participants' motivations and perceptions of the projects, and provide insights on the antecedents of success of the application development.

A …


Development Of A Locomotion And Balancing Strategy For Humanoid Robots, Emile Bahdi Jan 2018

Development Of A Locomotion And Balancing Strategy For Humanoid Robots, Emile Bahdi

Electronic Theses and Dissertations

The locomotion ability and high mobility are the most distinguished features of humanoid robots. Due to the non-linear dynamics of walking, developing and controlling the locomotion of humanoid robots is a challenging task. In this thesis, we study and develop a walking engine for the humanoid robot, NAO, which is the official robotic platform used in the RoboCup Spl. Aldebaran Robotics, the manufacturing company of NAO provides a walking module that has disadvantages, such as being a black box that does not provide control of the gait as well as the robot walk with a bent knee. The latter disadvantage, …


Photochemistry Of Polycyclic Aromatic Hydrocarbons With Environmentally Relevant Metals, John P. Haynes Jan 2018

Photochemistry Of Polycyclic Aromatic Hydrocarbons With Environmentally Relevant Metals, John P. Haynes

Electronic Theses and Dissertations

The details of the work presented in this dissertation focus on simulated reactions in the atmosphere and water systems between persistent aromatic compounds and varying species of metals with an emphasis on iron. Bulk water suspensions of a standard soil and polycyclic aromatic hydrocarbons (PAH) were analyzed for soluble iron by inductively-coupled plasma mass spectroscopy (ICP-MS) following a 16 hour reaction period using simulated sunlight. Significant increases in soluble iron were only seen with 2-3 ring linear PAH and carboxylic acids.

A two-stage study was conducted to investigate the potential for and possible mechanisms involving the photo-oxidation of PAH into …


Application Of Evolutionary Network Concept In Structuring Mathematics Curriculum, Aditi Mitra Jan 2018

Application Of Evolutionary Network Concept In Structuring Mathematics Curriculum, Aditi Mitra

Electronic Theses and Dissertations

Phylogenetic tree and in general, evolutionary network, has found its application well beyond the biological fields and has even percolated into recent high demanding areas, such as data mining and social media chain reactions. An extensive survey of its current applications are presented here. An attempt has been made to apply the very concept in the mathematics course curriculum inside a degree program. Various features of the tree structure are identified within the curriculum network. To highlight various key components and to enhance the visual effect, several diagrams are presented. The combined effect of these diagram provides a sense of …


Exploring New Synthetic Strategies By Using Novel Manganese Carboxylate Complexes Along With Two Alkoxide Based Ligands, 2-(Hydroxymethyl)-Pyridine And 4,5-Bis(Hydroxymethyl)-2-Methylpyridin-3-Ol In The Area Of Polynuclear Coordination Chemistry, Michael A. Reagan Jan 2018

Exploring New Synthetic Strategies By Using Novel Manganese Carboxylate Complexes Along With Two Alkoxide Based Ligands, 2-(Hydroxymethyl)-Pyridine And 4,5-Bis(Hydroxymethyl)-2-Methylpyridin-3-Ol In The Area Of Polynuclear Coordination Chemistry, Michael A. Reagan

Electronic Theses and Dissertations

Manganese carboxylate complexes have been well studied in the past, due to their relevance in bioinorganic chemistry and as well as their behavior as nanoscale magnetic materials that is called single-molecule magnets (SMMs). SMMs are special class of magnetic materials in which magnetism is intrinsic to the molecule. Polynuclear manganese clusters often possess high spin ground states as well as large and negative magnetoanisotropy, a combination which leads to an energy barrier for the reversal of the magnetization direction. The paramagnetic nature of manganese at its common oxidation states with an ample number of unpaired electrons often leads to high-nuclearity …


Isolated Mobile Malware Observation, Augustine Paul Jan 2018

Isolated Mobile Malware Observation, Augustine Paul

Electronic Theses and Dissertations

The idea behind Bring Your Own Device (BYOD) it that personal mobile devices can be used in the workplace to enhance convenience and flexibility. This development encourages organizations to allow access of personal mobile devices to business information and systems for businesses operation. However, BYOD opens a firm to various security risks such as data contamination and the exposure of user interest to criminal activities. Mobile devices were not designed to handle intense data security and advanced security features are frequently turned off. Using personal mobile devices can also expose a system to various forms of security threats like malware. …


Selective Carbon-Carbon Bond Formation Promoted By Divalent Samarium Reagents, Christopher David-James Aretz Jan 2018

Selective Carbon-Carbon Bond Formation Promoted By Divalent Samarium Reagents, Christopher David-James Aretz

Electronic Theses and Dissertations

Three efficient methods for synthesis of five membered carbocycles, a highly understudied product motif in samarium(II) chemistry, were explored and optimized. These methods utilized simple starting materials to generate linear substrates with functional groups that are reactive towards samarium(II) iodide. The three methods explored were the Reformatsky-aldol, Reformatsky-alkylation, and pinacol cyclizations. The critical discovery for efficient formation of the Reformatsky-aldol and pinacol carbocycles products was the use of lithium bromide. This addition of lithium bromide facilitates easy in situ formation of samarium(II) bromide. The Reformatsky-alkylation cyclization was a newly realized reaction employing samarium enolates. Two of the three methods, the …


Heat, Charge And Spin Transport Of Thin Film Nanostructures, Devin John Wesenberg Jan 2018

Heat, Charge And Spin Transport Of Thin Film Nanostructures, Devin John Wesenberg

Electronic Theses and Dissertations

Understanding of fundamental physics of transport properties in thin film nanostructures is crucial for application in spintronic, spin caloritronics and thermoelectric applications. Much of the difficulty in the understanding stems from the measurement itself. In this dissertation I present our thermal isolation platform that is primarily used for detection of thermally induced effects in a wide variety of materials. We can accurately and precisely produce in-plane thermal gradients in these membranes, allowing for thin film measurements on 2-D structures. First, we look at thermoelectric enhancements of doped semiconducting single-walled carbon nanotube thin films. We use the Wiedemann-Franz law to calculate …


Brønsted Acid Catalyzed Carbon-Carbon Bond Forming Reactions, Jiangyue Miao Jan 2018

Brønsted Acid Catalyzed Carbon-Carbon Bond Forming Reactions, Jiangyue Miao

Electronic Theses and Dissertations

The focus of this research project lies in the development of new methodology in the field of Brønsted acid catalysis enabling rapid synthesis of medicinally relevant compounds. It is foreseen that small molecule sulfonic acids evaluated in this research project will unveil new asymmetric carbon carbon bond forming reactions between substrates hitherto unexplored with Brønsted acid catalysis. It has been established that strong Brønsted acids, such as phosphoric acids, are capable of mediating highly selective transformations operating through unique mechanistic manifolds.

Specific focus for the sulfonic acid catalysts was geared towards asymmetric coupling reactions with synthetically useful precursors such as …


Automated Cfd Optimization To Maximize Wind Farms Performance And Land Use, Rafael Valotta Rodrigues Jan 2018

Automated Cfd Optimization To Maximize Wind Farms Performance And Land Use, Rafael Valotta Rodrigues

Electronic Theses and Dissertations

In this research, a computational system was designed to analyze and optimize the layout of wind farms under variable operational conditions. At first, a wind turbine computational fluid dynamic (CFD) model was developed covering the near wake. The near wake flow field was validated against near wake velocity data from the MEXICO experiment. The CFD simulation demonstrated that the tip speed ratio and the pitch angle greatly influence the near wake behavior, affecting the velocity deficit and the turbulence intensity profile in this region. The CFD model was extended to cover the far wake, aiming to become a computational tool …


A Study Of Computational Problems In Computational Biology And Social Networks: Cancer Informatics And Cascade Modelling, Christopher Ma Jan 2018

A Study Of Computational Problems In Computational Biology And Social Networks: Cancer Informatics And Cascade Modelling, Christopher Ma

Electronic Theses and Dissertations

It is undoubtedly that everything in this world is related and nothing independently exists. Entities interact together to form groups, resulting in many complex networks. Examples involve functional regulation models of proteins in biology, communities of people within social network. Since complex networks are ubiquitous in daily life, network learning had been gaining momentum in a variety of discipline like computer science, economics and biology. This call for new technique in exploring the structure as well as the interactions of network since it provides insight in understanding how the network works and deepening our knowledge of the subject in hand. …


A Survey Of Clustering Analysis And Clustering Analysis In Graphs, Raven D. Gilmore Jan 2018

A Survey Of Clustering Analysis And Clustering Analysis In Graphs, Raven D. Gilmore

Electronic Theses and Dissertations

Clustering analysis is an important topic in data mining, where data points that are similar to each other are grouped together. Graph clustering deals with clustering analysis of data points that correspond to vertices on a graph. We first survey some most well known algorithms for clustering analysis. Then for graph clustering we note that one of the fundamental factors is the distance measure between vertices. We further examine various known venues for defining such measures and propose some others.


A Comparison Of Bridge Deterioration Models, Toktam Naderimoghaddam Jan 2018

A Comparison Of Bridge Deterioration Models, Toktam Naderimoghaddam

Electronic Theses and Dissertations

Predicting how bridges will deteriorate is the key to budgeting financial and personnel resources. Deterioration models exist for specific components of a bridge, but no models exist for the sufficiency rating which is an overall measure of the condition and relevance of a bridge used for determining eligibility for federal funds.

We have 25 years worth of data collected by the Georgia Department of Transportation from 1992 to 2016 about all bridges in the State of Georgia. More precisely, each row in this data set includes the characteristics of each bridge along with the sufficiency rating of that bridge in …


Blow Up Solution Of Bose-Einstein Condensates With Anisotropic Trapping Potential And Rotation, Christopher Leonard Jan 2018

Blow Up Solution Of Bose-Einstein Condensates With Anisotropic Trapping Potential And Rotation, Christopher Leonard

Electronic Theses and Dissertations

In this paper we will analyze a nonlinear Schrodinger equation with quadratic anisotropic trapping potential used to describe a Bose-Einstein condensate. We will find sufficient condition for the global existence of the solution and for the blow up result using physical properties associated to the equation such as the mass, energy, and angular momentum along with some other identities related to the equation. We will finish the thesis with showing some graphical representations describing the solution of the equation.


Survey Of Results On The Schrodinger Operator With Inverse Square Potential, Richardson Saint Bonheur Jan 2018

Survey Of Results On The Schrodinger Operator With Inverse Square Potential, Richardson Saint Bonheur

Electronic Theses and Dissertations

In this paper we present a survey of results on the Schrodinger operator with Inverse ¨ Square potential, La= −∆ + a/|x|^2 , a ≥ −( d−2/2 )^2. We briefly discuss the long-time behavior of solutions to the inter-critical focusing NLS with an inverse square potential(proof not provided). Later we present spectral multiplier theorems for the operator. For the case when a ≥ 0, we present the multiplier theorem from Hebisch [12]. The case when 0 > a ≥ −( d−2/2 )^2 was explored in [1], and their proof will be presented for completeness. No improvements on the sharpness …


Paleoflood Hydrology And Basin Morphometric Characteristics Related To Flooding In The Colorado Front Range, Natalie Trivino Jan 2018

Paleoflood Hydrology And Basin Morphometric Characteristics Related To Flooding In The Colorado Front Range, Natalie Trivino

Electronic Theses and Dissertations

Flooding hazards are common in the Colorado Front Range due to the steep, complex terrain of the mountains where waters quickly spill out onto the most populated region of Colorado. This region has experienced numerous catastrophic floods, such as the 2013 Front Range Floods, the Fort Collins Flood of 1997, and the Big Thompson Canyon Flood of 1976 to name a few. The objective of this study was to analyze basin morphometric characteristics of several drainage basins throughout the Colorado Front Range South Platte River tributaries and determine how these characteristics relate to extreme flooding. This was done through three …


The Investigation Of Lactoferrin Nitration: Quantification, Function, And Inhibition, Amani Yahya Alhalwani Jan 2018

The Investigation Of Lactoferrin Nitration: Quantification, Function, And Inhibition, Amani Yahya Alhalwani

Electronic Theses and Dissertations

Lactoferrin (LF) is an iron-binding glycoprotein of molecular mass ca. 80 kDa that is predominantly found in mammalian body fluids. Lactoferrin is a multifunctional protein that has a wide range of properties such as antibacterial, antiviral, anti-inflammatory, and anti-allergic functions. Tyrosine residues in the protein play a part in many lactoferrin functions. Protein tyrosine nitration modification represents an oxidative and nitrosative stress process which can be caused by the exposure of proteins to oxidants from air pollution or disease. Understanding the way nitrated lactoferrin interacts with the biochemical environment of the body is thus important to the broader goal of …


Algorithmic Music Generation For Pedagogy Of Sight Reading, Ryan Stephen Davis Jan 2018

Algorithmic Music Generation For Pedagogy Of Sight Reading, Ryan Stephen Davis

Electronic Theses and Dissertations

Autodeus is the name of the program that has been developed and was designed to aid guitar students in the attainment and betterment of musical notation sight reading skills. Its primary goal is to provide a very flexible tool that has the ability to generate virtually endless types of sight reading exercises at many various skill levels.

A complimentary 2 year-long comprehensive guitar sight-reading course syllabus can be implemented via Autodeus as it is capable of generating all the necessary exercises. It is able to generate these exercises quickly and efficiently through the use of a back tracking algorithm that …


Experimental Investigation Of Impurities And Their Effect On Acousto-Electric Properties Of Lithium Niobate, Chandrima Chatterjee Jan 2018

Experimental Investigation Of Impurities And Their Effect On Acousto-Electric Properties Of Lithium Niobate, Chandrima Chatterjee

Electronic Theses and Dissertations

No abstract provided.


Modernized Approach For Generating Micro-Layering And Macro-Heterogeneous Structures In Porous Media For Use In Transmitted-Light Method Flow Visualization Experiments, Aaron A. Jones Jan 2018

Modernized Approach For Generating Micro-Layering And Macro-Heterogeneous Structures In Porous Media For Use In Transmitted-Light Method Flow Visualization Experiments, Aaron A. Jones

Electronic Theses and Dissertations

Image capturing in flow experiments has been used for fluid mechanics research since the early 1970s. Interactions of fluid flow between the vadose zone and permanent water table are of great interest to researchers because this zone is responsible for all recharge waters, pollutant transport and even irrigation efficiency for agriculture. Griffith, et al. (2011) developed an approach where constructed reproducible “geologically realistic” sand configurations are deposited in sand-filled experimental chambers or cells for light-transmitted flow visualization experiments. This method creates reproducible, reverse graded, layered (stratified) thin-slab sand chambers for visualizing multiphase flow through porous media. Reverse-graded stratification of sand …


Synthesis And Evaluation Of Dual-Acting Ligands For Mu Opioid And Neuropeptide Ff Receptors, Kelsey Gabrielle Mcpherson Jan 2018

Synthesis And Evaluation Of Dual-Acting Ligands For Mu Opioid And Neuropeptide Ff Receptors, Kelsey Gabrielle Mcpherson

Electronic Theses and Dissertations

Pain, although subjective, is an unpleasant sensation caused by a noxious stimulus, that effects millions of people every year. Currently, the most frequently prescribed class of analgesics for moderate to severe acute and sometime chronic pain are opioid analgesics, most commonly ?-opioid receptor (MOP) agonists, such as oxycodone, morphine, and fentanyl. Although these drugs provide significant pain relief, they are also associated with unwelcome side effects such as constipation, addiction, physical dependence, respiratory depression, and physiological tolerance that leads to hyperalgesia. Receptor desensitization due to excessive receptor activation by an agonist is but one source of physiological tolerance; it can …


Generalized Characteristics Of A Generic Polytope, Tommy Naugle Jan 2018

Generalized Characteristics Of A Generic Polytope, Tommy Naugle

Electronic Theses and Dissertations

For a smooth hypersurface S ⊂ R 2n given by the level set of a Hamiltonian function H, a symplectic form ω on R2n induces a vector field XH which flows tangent to S. By the nondegeneracy of ω, there exists a distinguished line bundle LS whose characteristics are the integral curves of XH. When S is the boundary of a smooth convex domain K˜ ⊂ R 2n, then the least action among closed characteristics of LS is equal to the Ekeland-Hofer-Zehnder capacity, a symplectic invariant. From a result due to Artstein-Avidan and Ostrover, there exists a continuous extension of …


Building An Autonomous Indoor Drone System, Hunter Gossett Jan 2018

Building An Autonomous Indoor Drone System, Hunter Gossett

Electronic Theses and Dissertations

This thesis presents an indoor autonomous drone system using a self assembled drone which uses a companion computer as well as external sensors for autonomous flight. While autonomous drone systems have been around for some time, originating with the military, the vast majority of them are designed for outdoor use, because of their heavy reliance on GPS for their positioning systems. In order to achieve autonomous flight indoors we choose to use simultaneous localization and mapping (slam) as our positioning system. The contributions of this thesis is an in depth guide to the hardware and assembly of a drone system, …


Bases In Spaces Of Regular Multilinear Operators And Homogeneous Polynomials On Banach Lattices, Khazhak Varazdat Navoyan Jan 2018

Bases In Spaces Of Regular Multilinear Operators And Homogeneous Polynomials On Banach Lattices, Khazhak Varazdat Navoyan

Electronic Theses and Dissertations

For Banach lattices E1,…, Em and F with 1-unconditional bases, we show that the monomial sequence forms a 1-unconditional basis of Lr(E1,…, Em;F), the Banach lattice of all regular m-linear operators from E1×···× Em to F, if and only if each basis of E1,…,Em is shrinking and every positive m-linear operator from E 1×···×Em to F is weakly sequentially continuous. As a consequence, we obtain necessary and sufficient conditions for which the m-fold Fremlin projective tensor product E1⊗ |π|··· ⊗|π|E m (resp. the m-fold positive injective tensor product E1⊗|ϵ|··· ⊗ |ϵ|Em) has a shrinking basis or a boundedly complete basis. …


Non-Hermitian Optics, Absar Ulhassan Jan 2018

Non-Hermitian Optics, Absar Ulhassan

Electronic Theses and Dissertations

From the viewpoint of quantum mechanics, a system must always be Hermitian since all its corresponding eigenvalues must be real. In contrast, the eigenvalues of open systems-unrestrained because of either decay or amplification-can be in general complex. Not so long ago, a certain class of non-Hermitian Hamiltonians was discovered that could have a completely real eigenvalue spectrum. This special class of Hamiltonians was found to respect the property of commutation with the parity-time (PT) operator. Translated into optics, this implies a balance between regions exhibiting gain and loss. Traditionally, loss has been perceived as a foe in optics and something …


Impact Of Ionizing Radiation And Electron Injection On Carrier Transport Properties In Narrow And Wide Bandgap Semiconductors, Jonathan Lee Jan 2018

Impact Of Ionizing Radiation And Electron Injection On Carrier Transport Properties In Narrow And Wide Bandgap Semiconductors, Jonathan Lee

Electronic Theses and Dissertations

This study investigated the minority carrier properties of wide and narrow bandgap semiconductors. Included specifically are wide bandgap materials GaN and β-Ga2O3, and narrow bandgap InAs/GaSb type-II strain-layer superlattice. The importance of minority carrier behavior in bipolar device performance is utmost because it is the limiting component in current conduction. The techniques used to determine minority carrier properties include electron beam induced current (EBIC) and cathodoluminescence (CL) spectroscopy. The CL spectroscopy is complemented with time-resolved CL (TRCL) for direct measurement of carrier radiative recombination lifetime. The minority carrier properties and effect of high energy radiation is explored. The GaN TRCL …


A Value Sensitive Design Approach To Adolescent Mobile Online Safety, Arup Kumar Ghosh Jan 2018

A Value Sensitive Design Approach To Adolescent Mobile Online Safety, Arup Kumar Ghosh

Electronic Theses and Dissertations

With the rise of adolescent smartphone use, concerns about teen online safety are also on the rise. A number of parental control apps are available for mobile devices, but adoption of these apps has been markedly low. To better understand these apps, their users, and design opportunities in the space of mobile online safety for adolescents, we have conducted four studies informed by the principles of Value Sensitive Design (VSD). In Study 1 (Chapter 2), we conducted a web-based survey of 215 parents and their teens (ages 13-17) using two separate logistic regression models (parent and teen) to examine the …


Environmental Physical-Virtual Interaction To Improve Social Presence With A Virtual Human In Mixed Reality, Kangsoo Kim Jan 2018

Environmental Physical-Virtual Interaction To Improve Social Presence With A Virtual Human In Mixed Reality, Kangsoo Kim

Electronic Theses and Dissertations

Interactive Virtual Humans (VHs) are increasingly used to replace or assist real humans in various applications, e.g., military and medical training, education, or entertainment. In most VH research, the perceived social presence with a VH, which denotes the user's sense of being socially connected or co-located with the VH, is the decisive factor in evaluating the social influence of the VH—a phenomenon where human users' emotions, opinions, or behaviors are affected by the VH. The purpose of this dissertation is to develop new knowledge about how characteristics and behaviors of a VH in a Mixed Reality (MR) environment can affect …


A Decision Support Tool For Video Retinal Angiography, Sumit Laha Jan 2018

A Decision Support Tool For Video Retinal Angiography, Sumit Laha

Electronic Theses and Dissertations

Fluorescein angiogram (FA) is a medical procedure that helps the ophthalmologists to monitor the status of the retinal blood vessels and to diagnose proper treatment. This research is motivated by the necessity of blood vessel segmentation of the retina. Retinal vessel segmentation has been a major challenge and has long drawn the attention of researchers for decades due to the presence of complex blood vessels with varying size, shape, angles and branching pattern of vessels, and non-uniform illumination and huge anatomical variability between subjects. In this thesis, we introduce a new computational tool that combines deep learning based machine learning …