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The Use Of Stable Isotopes And Particulate Matter In The Investigation Of Local And Regional Atmospheric Chemistry, Tanya Lynn Katzman Aug 2016

The Use Of Stable Isotopes And Particulate Matter In The Investigation Of Local And Regional Atmospheric Chemistry, Tanya Lynn Katzman

Open Access Dissertations

The chemical composition of particulate matter (PM), a known contributor to air pollution, is highly variable, and elemental analysis reveals information about local and regional sources, as well as how air masses and climate influence PM compositions. Seasonal changes in climate, such as temperature, amount of daylight, or meteorological patterns influence source emissions (increased residential heating activities, decreased natural soil emissions) and the relative importance of certain chemical pathways in the atmosphere. Since the magnitude of these seasonal changes are highly dependent on location, each sampling site is unique and the chemical composition of PM provides valuable insight into local …


Connecting Models Of Configuration Spaces: From Double Loops To Strings, Jason M. Lucas Aug 2016

Connecting Models Of Configuration Spaces: From Double Loops To Strings, Jason M. Lucas

Open Access Dissertations

Foundational to the subject of operad theory is the notion of an En operad, that is, an operad that is quasi-isomorphic to the operad of little n-cubes Cn. They are central to the study of iterated loop spaces, and the specific case of n = 2 is key in the solution of the Deligne Conjecture. In this paper we examine the connection between two E 2 operads, namely the little 2-cubes operad C 2 itself and the operad of spineless cacti. To this end, we construct a new suboperad of C2, which we name the operad of tethered …


Protein Lc-Ms Using Slip Flow Chromatography, Ximo Zhang Aug 2016

Protein Lc-Ms Using Slip Flow Chromatography, Ximo Zhang

Open Access Dissertations

Histones are essential chromosomal proteins with large numbers of variants and post-translational modifications (PTMs). PTM levels of histones are known to correlate with different stages of cancer. Due to the lack of resolution on intact histone separations, conventional methods for histone analysis require time-consuming digestion, which often leads to the loss of PTM information. Slip flow chromatography with orderly packed nonporous silica particles has been shown to greatly increase the efficiency of protein separation by reducing eddy diffusion and resistance to mass transfer. In this work, higher resolution for intact histones separation was achieved by using a 5 cm capillary …


The Effects Of Scarring On Face Recognition, Kevin J. Chan Aug 2016

The Effects Of Scarring On Face Recognition, Kevin J. Chan

Open Access Theses

The focus of this research is the effects of scarring on face recognition. Face recognition is a common biometric modality implemented for access control operations such as customs and borders. The recent report from the Special Group on Issues Affecting Facial Recognition and Best Practices for their Mitigation highlighted scarring as one of the emerging challenges. The significance of this problem extends to the ISO/IEC and national agencies are researching to enhance their intelligence capabilities. Data was collected on face images with and without scars, using theatrical special effects to simulate scarring on the face and also from subjects that …


Image Quality Estimation: Soft-Ware For Objective Evaluation, He Liu Aug 2016

Image Quality Estimation: Soft-Ware For Objective Evaluation, He Liu

Open Access Theses

Digital images are widely used in our daily lives and the quality of images is important to the viewing experience. Low quality images may be blurry or contain noise or compression artifacts. Humans can easily estimate image quality, but it is not practical to use human subjects to measure image quality in real applications. Image Quality Estimators (QE) are algorithms that evaluate image qualities automatically. These QEs compute scores of any input images to represent their qualities. This thesis mainly focuses on evaluating the performance of QEs. Two approaches used in this work are objective software analysis and the subjective …


Automating Stem Learning By Engaging In Artful-Inspired Play, Katie E. Roth Aug 2016

Automating Stem Learning By Engaging In Artful-Inspired Play, Katie E. Roth

Open Access Theses

A full range of experimental methodologies split between two distinct yet related projects was performed in an effort to define ways to automate STEM learning in artful-inspired play. Both projects aim to offer impactful learning experiences through artful-inspired activities meant to automate STEM (science, technology, engineering, mathematics) learning in children that are both scientifically and non-scientifically inclined. By participating in play that is both fun and engaging, learning is a byproduct of the activity which acts to automatically embed STEM knowledge and experiences within the user. Bridging the gap between STEM and artistic tendencies has the potential to provide a …


A Study Of Applications Of 3d Animation For Emergency Medicine Pedagogy, Huilong Zheng Aug 2016

A Study Of Applications Of 3d Animation For Emergency Medicine Pedagogy, Huilong Zheng

Open Access Theses

There is ample precedent for the use of 3D animation in education, though little research on specific applications in the field of medicine. An experiment was carried out to assess the suitability of 3D animation for educational purposes in emergency medicine courses. Two groups of experimental participants were assessed on their ability to respond to three emergency medical situations in simulated test scenarios. Both groups received equivalent information on how to treat the three different medical emergencies. The control group received the information in traditional lecture format. The experimental group instead received the information from a set of 3D animations. …


Localization And Delocalization In Two-Dimensional Quantum Percolation, Brianna S. Dillon Thomas Aug 2016

Localization And Delocalization In Two-Dimensional Quantum Percolation, Brianna S. Dillon Thomas

Open Access Dissertations

Quantum percolation is one of several disorder-only models that address the question of whether conduction, or more generally, delocalization, is possible in two dimensional disordered systems. Whether quantum percolation exhibits a delocalization-localization phase transition in two dimensions is an ongoing debate, but many recent studies point toward there being a delocalized phase at non-zero disorder, in contradiction to the behavior of the Anderson model, another disorder-only model. In this dissertation, I present my research on quantum percolation that shows a delocalized state is possible, both on isotropic lattices and on highly anisotropic lattices, and shows that the essential characteristics of …


A Usability Assessment For A Career Planning Educational Video Game, Jiaqi Wang Aug 2016

A Usability Assessment For A Career Planning Educational Video Game, Jiaqi Wang

Open Access Theses

This study focused on the design, implementation and usability assessment of an educational 2D iPad job matching game The Place You’ll Go (TPYG), which meant for matching student skill sets with career profiles. The development of the game is conducted in collaboration with Purdue University’s Krannert School of Management and Polytech Institute. A total of 7 subjects, as high school teachers, participated in the usability study. TPYG as one possible solution for job matching data visualization, did not provide players with a good experience. However, conclusions and findings can be used in similar education game development. Based on survey and …


Promoting Teaming Metacognition, Lee Kemp Rynearson Aug 2016

Promoting Teaming Metacognition, Lee Kemp Rynearson

Open Access Dissertations

Improving students’ capacity to effectively perform teaming skills is a crucial outcome for engineering education, and has been the subject of considerable prior and ongoing research. Based upon review of research on teaming, it was hypothesized that greater awareness of appropriate opportunities to use teaming skills in authentic contexts would lead to greater teaming skills employment over time. Further, it was hypothesized that greater psychological safety in student teams would lead to more students choosing to employ appropriate teaming skills over time. An intervention to achieve such increases could therefore be expected to promote student teaming skills performance improvement. Seeking …


Particle Modeling Of Non-Equilibrium Field Emission Driven Rf Microplasmas, Siva Sashank Tholeti Aug 2016

Particle Modeling Of Non-Equilibrium Field Emission Driven Rf Microplasmas, Siva Sashank Tholeti

Open Access Dissertations

Non-equilibrium microplasmas at atmospheric pressures have been investigated for active flow control, micropropulsion and electronic display applications to name a few. The operational voltages for these microplasmas are on the order of kilovolts. When the electric field at the electrodes reaches GV/m or tens of GV/m either due to reduced interelectrode spacing and surface irregularities or due to carefully designed nanostructures on the electrodes, quantum processes such as field emission and field ionization come into effect. These can potentially reduce the operational voltages of microplasma devices by an order of magnitude. Due to the rarefied and non-equilibrium nature of these …


Essays In International Migration, Marcelo J. Castillo Aug 2016

Essays In International Migration, Marcelo J. Castillo

Open Access Dissertations

This dissertation consists of three essays examining the effects of high-skilled immigration on various economic outcomes within the receiving country. In the first essay, I study how skilled immigrants affect wages and employment in US industries during 1995-2007, using novel microdata on approved H-1B visas. These data show that most H-1B employers specialize in the production of high-skilled services used as inputs by other businesses. In light of this, I consider the downstream effects of skilled immigrants on industry labor market outcomes: how wages and employment in an industry respond to immigration shocks to its suppliers. The identification strategy relies …


Intestinal Adaptation To Repeated Exposure Of Flavonoid-Rich Foods: In Vitro And Clinical Data, Bejamin W. Redan Aug 2016

Intestinal Adaptation To Repeated Exposure Of Flavonoid-Rich Foods: In Vitro And Clinical Data, Bejamin W. Redan

Open Access Dissertations

Interest in application of flavonoids for chronic disease prevention has grown significantly, but the low oral bioavailability of these compounds from acute doses is commonly highlighted as a limitation when considering their biological significance. Still, the impact of broad dietary patterns such as repeated exposure on flavonoid’s absorption, metabolism, and eventual efficacy is critical to consider since evidence suggests that their bioavailability may be enhanced with repeated exposure. To fill this gap in knowledge, this dissertation will focus on three major areas including characterization of flavonoid metabolites, in addition to use of in vitro models and clinical work to test …


Two-Particle Correlation Studies In Heavy Ion Collisions At The Large Hadron Collider, Lingshan Xu Aug 2016

Two-Particle Correlation Studies In Heavy Ion Collisions At The Large Hadron Collider, Lingshan Xu

Open Access Dissertations

Results on two-particle angular correlations in pPb at [square root sNN] =5.02 TeV and PbPb collisions at [square root sNN] =2.76 TeV are reported. The long-range correlations in pseudorapidity (“ridge'') has been seen in various systems, including PbPb, pPb and pp systems. In this thesis, two-particle correlations in pPb collisions at nucleon-nucleon center-of-mass energy of 5.02 TeV are studied as a function of the pseudorapidity separation (Δ η) of the particle pair at small azimuthal angle separation (|Δ&phis;| < π/3). The correlations are decomposed into a jet component that dominates the short-range correlations (|Δη| < 1), and a component that persists at large Δη, which is the ridge. The ridge may be associated with collective behavior of the produced system, well …


Implementation Of Reliability Aware Scheduling In An Open Source Scheduling System, Monica Marathe Aug 2016

Implementation Of Reliability Aware Scheduling In An Open Source Scheduling System, Monica Marathe

Open Access Theses

High performance computing clusters provide an efficient and cost effective solution to tackle large and complex problems. These clusters make use of the computing power available from widely available and relatively inexpensive commodity hardware. However, commodity hardware is liable to frequent failures, which can cause processes that are executing on these components to fail. Hence, high performance clusters often suffer from poor reliability. Whenever failures occur, additional costs are generated which lead to an increase in the cost of running the cluster. To prevent processes from failing, proactive fault tolerance strategies may be used in these cluster systems. The scheduler …


Improving Cloud Middlebox Infrastructure For Online Services, Rohan S. Gandhi Aug 2016

Improving Cloud Middlebox Infrastructure For Online Services, Rohan S. Gandhi

Open Access Dissertations

Middleboxes are an indispensable part of the datacenter networks that provide high availability, scalability and performance to the online services. Using load balancer as an example, this thesis shows that the prevalent scale-out middlebox designs using commodity servers are plagued with three fundamental problems: (1) The server-based layer-4 middleboxes are costly and inflate round-trip-time as much as 2x by processing the packets in software. (2) The middlebox instances cause traffic detouring en route from sources to destinations, which inflates network bandwidth usage by as much as 3.2x and can cause transient congestion. (3) Additionally, existing cloud providers do not support …


Synthesis, Characterization, And Application Of Magnetic Gold Nanoclusters, Naveen Reddy Kadasala Aug 2016

Synthesis, Characterization, And Application Of Magnetic Gold Nanoclusters, Naveen Reddy Kadasala

Open Access Dissertations

Au–Fe3O4 nanocomposites are of great interest for technological reasons due to their combined optical and magnetic properties. Nanosized Fe3O4 particles are superparamagnetic and can also be coated with a layer of Au, which supports localized plasmon resonances for useful optical properties. The dual properties of Au–Fe3O 4 nanoparticles have inspired chemists to design a variety of synthetic routes, some with good control of overall shape and size. However, most approaches require organic solvents, surfactants, or harsh chemical conditions. In this thesis we describe a simple and highly reproducible synthesis of magnetically active gold nanoclusters (MGNCs) with average particle sizes under …


Mass Spectrometric Characterization Of Remotely Charged Amino Acids And Peptides, Damodar Koirala Aug 2016

Mass Spectrometric Characterization Of Remotely Charged Amino Acids And Peptides, Damodar Koirala

Open Access Dissertations

Ion–molecule reactions in a flowing afterglow are used to examine the electronic structure of 3- and 4-pyridinylnitrene-n-oxide radical anions. Reactions with nitric oxide are generally similar to those reported previously for other aromatic nitrene radical anions. In particular, phenoxide formation by nitrogen–oxygen exchange is observed with both isomers. Oxygen atom abstraction by NO is also observed with both isomers. Very significant differences in the reactivity are observed in the reactions of the two isomers with carbon disulfide. The reactivity of the 3-noxide isomer with CS2 is similar to that observed previously for nitrene radical anions, and reactions of the n-oxide …


Manufacturer Perspectives On Content Transparency And Material Health In The Us Building Products Industry, Alexandra A. Muller Aug 2016

Manufacturer Perspectives On Content Transparency And Material Health In The Us Building Products Industry, Alexandra A. Muller

Open Access Theses

Flawed U.S. federal regulation of chemicals has resulted in a materials market that undervalues human and environmental health in favor of the more traditional attributes of price, performance and aesthetics. In the building products industry, global, dynamic supply chains and proprietary information concerns further complicate the task of assessing the material health of products.

Voluntary material health programs in the green building industry are intended to incentivize the manufacture and selection of safer products by getting companies to gather and assess ingredient, hazard and risk information from their supply chain. Building product manufacturers considered early adopters of the main material …


Analysis Of Feedback Control Applied With Command Shaping To Minimize Residual Vibration, Nicholas L. Jacobs Aug 2016

Analysis Of Feedback Control Applied With Command Shaping To Minimize Residual Vibration, Nicholas L. Jacobs

Open Access Theses

Joint flexibility is a physical trait that affects all robotic systems to some degree. This characteristic has been shown to be very detrimental to the performance of these robotic systems when implementing fast point-to-point motion. During such motion, the robot will induce vibrations in its structure that will extend past the completion of the move. Many techniques have been applied over the years in order to minimize these residual vibrations. One such method is known as command shaping, which will construct the input profile so as to avoid exciting the natural frequencies of the system. This work seeks to extend …


Simulation Of Flow And Water Quality From Tile Drains At The Watershed And Field Scale, Colleen Moloney Aug 2016

Simulation Of Flow And Water Quality From Tile Drains At The Watershed And Field Scale, Colleen Moloney

Open Access Theses

Simulation models such as the Soil and Water Assessment Tool (SWAT) have become widely used in determining the water quality impacts of various management practices. Ensuring that the algorithms accurately represent the processes simulated has become an important goal. Tile drainage is a standard practice in the Midwest, US in order to reduce risk of yield loss due to excess water. Multiple tile drainage and water table algorithms have been available in the SWAT model between the initial SWAT release and revision 638 used in this study. Testing of those algorithms is often limited. Furthermore, algorithms in the current version …


Tool Comparison Of Semantic Parsers, Robert Hinh Aug 2016

Tool Comparison Of Semantic Parsers, Robert Hinh

Open Access Theses

Natural Language Processing (NLP) is a vital aspect for artificial intelligence systems to achieve integration into human lives, which has been a goal for researchers in this industry. While NLP focuses on an array of problems, semantic parsing will be specifically focused on throughout this paper. These parsers have been considerably targeted for improvement through the scientific community and demand for semantic parsers that achieve high accuracy has increased. There have been many approaches developed for this specific purpose and in this paper, a deep analysis was performed to compare the performance of semantic parsing systems. The implications of this …


Phase Field Damage Simulations Of Debonding Between Matrix And Spherical Inclusions, Johanna B. Palsdottir Aug 2016

Phase Field Damage Simulations Of Debonding Between Matrix And Spherical Inclusions, Johanna B. Palsdottir

Open Access Theses

Polymer-bonded explosives (PBX) are complicated composites, and it is important for practical applications to know how they deform and fracture. PBX consists of large volume fraction of energetic particles and experiments show that the interface is a critical region for structural stability since particles are often weakly bonded to the polymer and cracks initiate there and the composite fractures. This study focuses on the interface between a particle and a binder and how the particle inclusion starts to debond from the polymer binder in compressive and tensile loading.

A phase field damage model is used to model the response of …


Development Of A Novel Polymer-Garnet Solid State Composite Electrolyte Incorporating Li-La-Zr-Bi-O And Polyethylene Oxide, Muhammed Ramazan Oduncu Aug 2016

Development Of A Novel Polymer-Garnet Solid State Composite Electrolyte Incorporating Li-La-Zr-Bi-O And Polyethylene Oxide, Muhammed Ramazan Oduncu

Open Access Theses

Current lithium ion batteries are comprised of organic liquid electrolytes - a mixture of lithium salts and binary solvents such as ethylene carbonate (EC) and dimethyl carbonate (DMC). The main drawbacks of this liquid mixture related to safety are flammability of the organic solvents and chemical instability with the electrode materials. To date, various ceramic and polymer materials have been considered which overcome safety issues. However, a common problem of these solid state materials is that they are not able to provide high ionic conductivity at ambient temperatures. Garnet-type cubic Li7La 3Zr2O12 ceramic material has attracted much interest because of …


Catalytic Conversion Of Chlorite To Chlorine Dioxide By Non-Heme Complexes, Manasa Ramachandra Aug 2016

Catalytic Conversion Of Chlorite To Chlorine Dioxide By Non-Heme Complexes, Manasa Ramachandra

Open Access Theses

The oxyanions of chlorine (ClOx-, x=1-4) have diverse applications and are used in a variety of commercial products. They are very stable in an aqueous environment leading to water contamination, thereby posing a concern for the environment and human health. At the microbial level, the enzyme perchlorate reductase catalyzes the reduction of perchlorate (ClO4-) to chlorite (ClO2-) and chlorite dismutase further reduces chlorite to innocuous chloride (Cl -) and dioxygen (O2). Two non-heme complexes [Fe III-TAML]- (Tetraamido Macrocyclic Ligand), and [Mn II-(BnTPEN)] in the presence of peracetic acid (PAA) have been studied as catalysts for chlorite dismutation under ambient conditions. …


Cyclic Tensile Response Of A Polyurethane Material, Yizhou Nie Aug 2016

Cyclic Tensile Response Of A Polyurethane Material, Yizhou Nie

Open Access Theses

Polyurethane is one of the most widely used polymer materials in the world. With the increasing demand of polyurethane, its mechanical behaviors are particularly of interest. In particular, the response of the material under a quasi-static loading being subject to an impact load. To delineate the effect of rate change on the mechanical response of polyurethane, a tensile experiment was designed where the specimen is initially subjected to quasi-static tensile loading and then to high-rate cyclic tension within the same experiment. Constant strain-rate experiments at both quasi-static and high strain rates are also conducted. The analysis of the results leads …


Exploratory Study Of Students' Representational Fluency And Competence Of Electric Circuits, William Fernando Sandchez Cossio Aug 2016

Exploratory Study Of Students' Representational Fluency And Competence Of Electric Circuits, William Fernando Sandchez Cossio

Open Access Theses

Electric circuits are extensively used in today’s devices as computers, phones, cameras and others. This makes them a crucial topic in engineering because almost every engineering branch could be related of used them at different levels. Even though their importance, students often struggle during the learning process of circuit analysis topics. Additionally, other very important abilities for engineering students are the capacities to create, use, express and think about models and representations of technical concepts; and the capacities to translate and map from one representation to another. These abilities are known as representational competence and representational fluency respectively.

The purpose …


Using Big Data Analytics For Effective Six Sigma Project Selection, Anuja S. Rayarikar Aug 2016

Using Big Data Analytics For Effective Six Sigma Project Selection, Anuja S. Rayarikar

Open Access Theses

Food security is a global concern that is addressed by each nation in its unique way. The Public Distribution System (PDS) is the largest food security scheme in India, which distributes food commodities to citizens at subsidized rates.

The onset of technology has been reflected in the PDS and the system has undergone many reforms over the years. The automation of fair price shops (FPS) in the state of Andhra Pradesh in India is one such reform that was implemented in January 2015. The use of unique identification cards called “Aadhar cards” for authentication along with electronic point-of-sale (ePoS) devices …


High School Students' Motivations And Views Of Agriculture And Agricultural Careers Upon Completion Of A Pre-College Program, Andrea K. Scherer Aug 2016

High School Students' Motivations And Views Of Agriculture And Agricultural Careers Upon Completion Of A Pre-College Program, Andrea K. Scherer

Open Access Theses

Pre-college summer residential experiences hosted by a College of Agriculture have the potential to expose high school students to new career opportunities and fields of study that they may not have considered, and may influence agricultural literacy, perceptions of agriculture, and interest in agriculture. Engaging these students is important for meeting the demand for more students graduating with agriculture degrees prepared to solve 21st century challenges. The purpose of this study was to explore and describe the outcomes of two separate pre-college experiences, the Molecular Agriculture Summer Institute (MASI) and the Purdue Agribusiness Science Academy (PASA), and participating high school …


Firm Demography And Location Decisions In The United States After 1990, Francisco Albert Scott Aug 2016

Firm Demography And Location Decisions In The United States After 1990, Francisco Albert Scott

Open Access Theses

This thesis deals with firm formation and location choice of firms in the manufacturing (and commercial service) sector in the United States after 1990. The topics of firm formation and location choice are part of a wider field that is usually referred to as "firm demography.'' We start off with a description of the size structure of firms by looking at the evolution of the average size of manufacturing firms in counties in the USA between 1990 and 2011. We hypothesize that the size of manufacturing firms depends on the firm sizes in proximate regions as well as on the …