Physical Sciences and Mathematics Commons^™

Work Function Modification Of Metal Electrodes Via Printing Of Pedot:Pss And Carbon Nanotubes, Carly A. Jordan

Browse all Theses and Dissertations

Work function tunability of metal electrodes provides a route to improving performance of organic electronic devices. Using an electrode with a different work function changes the potential barrier at the polymer/electrode interface, leading to altered device characteristics, such as turn-on voltage in light emitting diodes or series resistance photodiodes. In this work, we explore work function modification by employing solution-based conducting materials, poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT:PSS) and carbon nanotubes (CNTs), printed as overcoatings on oxidized Ni. The capability of direct write technologies, namely inkjet and aerosol jet printing, to control thin film thickness is investigated. The correlation between film …

Processing And Interpretation Of Three-Component Borehole/Surface Seismic Data Over Gabor Gas Storage Field, Li Wei

Browse all Theses and Dissertations

Analysis of a seismic dataset recorded as part of a collaborative project between Wright State University, Spectraseis, Precision Geophysical, and Dominion East Ohio over the Gabor gas storage field, Canton, Ohio, is the topic of this study. Two types of sources (vibroseis and small seismic shot-holes) as well as three types of recording systems (passive 3C broadband on the surface, experimental 3C borehole sondes, and conventional 2D surface geophone profiles) were employed with different purposes. The shot hole explosives were calibration check-shots for the 3C borehole array repeatedly deployed at multiple levels. The vibrators of the conventional 2D seismic profiles …

Atmospheric Effects On Radar/Ladar Detection Of Seismic Activity, Michelle Frances Via

Browse all Theses and Dissertations

This thesis investigates how well ground vibrations can be detected at ladar or radar wavelengths and how the atmosphere may impact the observation of such activity. First understanding atmospheric hindrances at each of these wavelengths is helpful to prioritize by those yielding best transmission results. A prerequisite to the outdoor field experiment performed for this study involves analyzing atmospheric effects characterization at six probable wavelengths using the Laser Environmental Effects Definition and Reference tool (LEEDR) developed by the Air Force Institute of Technology's (AFIT) Center for Directed Energy (CDE). These wavelengths, selected from the shortwave infrared and microwave portions of …

Owl Query Answering Using Machine Learning, Todd Huster

Browse all Theses and Dissertations

The formal semantics of the Web Ontology Language (OWL) enables automated reasoning over OWL knowledge bases, which in turn can be used for a variety of purposes including knowledge base development, querying and management. Automated reasoning is usually done by means of deductive (proof-theoretic) algorithms which are either provably sound and complete or employ approximate methods to trade some correctness for improved efficiency. As has been argued elsewhere, however, reasoning methods for the Semantic Web do not necessarily have to be based on deductive methods, and approximate reasoning using statistical or machine-learning approaches may bring improved speed while maintaining high …

Computational Estimation Of The Pka's Of Purines And Related Compounds, Kara L. Geremia

Browse all Theses and Dissertations

The acid dissociation value pKa of a compound provides important information regarding the neutral and ionic forms of the compound present under different conditions. However, for many compounds experimental pKa values are not available, and for others the measured values are sometimes uncertain. Consequently, having a computational means for estimating pKa values can be of benefit for biochemical, pharmaceutical, polymer, and many other studies. Purines form a key group of bioactive compounds whose acid/base activities are of considerable interest. The purine class includes such diverse compounds as the nucleic acid bases adenine and guanine, the gout-related compound uric acid, the …

Orthogonal Moment-Based Human Shape Query And Action Recognition From 3d Point Cloud Patches, Huaining Cheng

Browse all Theses and Dissertations

With the recent proliferation of 3D sensors such as Light Detection and Ranging (LIDAR), it is essential to develop feature representation methods that can best characterize the point clouds produced by these devices. When these devices are employed in targeting and surveillance of human actions from both ground and aerial platforms, the corresponding point clouds of body shape often comprise low-resolution, disjoint, and irregular patches of points resulted from self-occlusions and viewing angle variations. The prevailing method of depth image analysis has the limitation of relying on 2D features that are not native representation of 3D spatial relationships. On the …

Determination Of Vp, Vs, Glacial Drift Thickness And Poisson's Ratio At A Site In Jay County, Indiana, Using Seismic Refraction And Multichannel Analysis Of Surface Wave (Masw) Analysis On A Common Data Set, Shamim Ahammod

Browse all Theses and Dissertations

In July 2013, an industry-scale seismic reflection survey was conducted at a site in northern Jay County, Indiana, by geophysics students and faculty of Wright State University. As a part of that effort, a separate near-surface seismic dataset was collected to examine the Vp, Vs, and Poisson's Ratio of the glacial drift and upper bedrock. This near-surface study successfully used a common dataset that was separately analyzed for both Vp (seismic refraction) and Vs (MASW) to calculate the Poisson's Ratio of the glacial drift and underlying bedrock. The driller's log for a water well near the east end of this …

Feature Extraction Using Dimensionality Reduction Techniques: Capturing The Human Perspective, Ashley B. Coleman

Browse all Theses and Dissertations

The purpose of this paper is to determine if any of the four commonly used dimensionality reduction techniques are reliable at extracting the same features that humans perceive as distinguishable features. The four dimensionality reduction techniques that were used in this experiment were Principal Component Analysis (PCA), Multi-Dimensional Scaling (MDS), Isomap and Kernel Principal Component Analysis (KPCA). These four techniques were applied to a dataset of images that consist of five infrared military vehicles. Out of the four techniques three out of the five resulting dimensions of PCA matched a human feature. One out of five dimensions of MDS matched …

Ontology Pattern-Based Data Integration, Adila Alfa Krisnadhi

Browse all Theses and Dissertations

Data integration is concerned with providing a unified access to data residing at multiple sources. Such a unified access is realized by having a global schema and a set of mappings between the global schema and the local schemas of each data source, which specify how user queries at the global schema can be translated into queries at the local schemas. Data sources are typically developed and maintained independently, and thus, highly heterogeneous. This causes difficulties in integration because of the lack of interoperability in the aspect of architecture, data format, as well as syntax and semantics of the data. …

Hydrologic And Temperature Regime Influence On Growth And Recruitment Of Fishes In An Upper Midwest Riverine Ecosystem, Brett Donald Nelson

All Graduate Theses, Dissertations, and Other Capstone Projects

The natural flow regime is often identified as the primary driver of ecological integrity in rivers. The Minnesota River basin is characterized by a row-crop agricultural landscape with an extensive network of drainage tiles and ditches to improve land productivity. Intensive surface and subsurface drainage alters flow regimes, increasing the magnitude and frequency of high flows. Changes in river hydrology lead to alterations in geomorphology, including increased bank erosion, channel widening, and downward incision that can lead to floodplain disconnection. Disruption of historical hydrology can alter energy flow and connection to specialized habitats subsequently affecting important aquatic communities and populations …

Features For Ranking Tweets Based On Credibility And Newsworthiness, Jacob W. Ross

Browse all Theses and Dissertations

We create a robust and general feature set for learning to rank algorithms that rank tweets based on credibility and newsworthiness. In previous works, it has been demonstrated that when the training and testing data are from two distinct time periods, the ranker performs poorly. We improve upon previous work by creating a feature set that does not over fit a particular year or set of topics. This is critical given how people utilize social media changes as time progresses, and the topics discussed vary. In addition, we are constantly gaining new tweet data. Thus, it is important to be …

Dna-Nucleobase Guanine As Passivation/Gate Dielectric Layer For Flexible Gfet-Based Sensor Applications, Adrienne Dee Williams

Browse all Theses and Dissertations

The main goal of this dissertation was two-fold: first, to study and design a graphene-based transistor environmentally friendly by replacing a standard substrate and gate dielectric with different flexible/rigid and biodegradable films and secondly, to study their effects on graphene's charge carrier mobility. A thin film of deoxyribonucleic acid nucleobase purine guanine deposited by physical vapor deposition onto up to ten layers of graphene that were transferred onto various rigid and flexible substrates was characterized more thoroughly. Several test platforms were fabricated with guanine 1) as a standalone gate dielectric, 2) as the control and 3) as a passivation layer …

Domain-Specific Document Retrieval Framework For Near Real-Time Social Health Data, Swapnil Soni

Browse all Theses and Dissertations

With the advent of web search and microblogging, the percentage of Online Health Information Seekers (OHIS) using these services to share and seek health information in real-time has increased exponentially. Recently, Twitter has emerged as one of the primary mediums for sharing and seeking of the latest information related to a variety of topics, including health information. Although Twitter is an excellent information source, the identification of useful information from the deluge of tweets is one of the major challenges. Twitter search is limited to keyword-based techniques to retrieve information for a given query and sometimes the results do not …

Automatic Emotion Identification From Text, Wenbo Wang

Browse all Theses and Dissertations

People's emotions can be gleaned from their text using machine learning techniques to build models that exploit large self-labeled emotion data from social media. Further, the self-labeled emotion data can be effectively adapted to train emotion classifiers in different target domains where training data are sparse.

Emotions are both prevalent in and essential to most aspects of our lives. They influence our decision-making, affect our social relationships and shape our daily behavior. With the rapid growth of emotion-rich textual content, such as microblog posts, blog posts, and forum discussions, there is a growing need to develop algorithms and techniques for …

Efficient Training Of Small Kernel Convolutional Neural Networks Using Fast Fourier Transform, Tyler Highlander

Browse all Theses and Dissertations

Convolutional neural networks (CNNs) are currently state-of-the-art for various classification tasks, but are computationally expensive. Propagating through the convolutional layers is very slow, as each kernel in each layer must sequentially calculate many inner products for a single forward and backward propagation which equates to O(N^2 n^2) per kernel per layer where the inputs are N x N arrays and the kernels are n x n arrays. Convolution can be efficiently performed as a Hadamard product in the frequency domain. The bottleneck is the transformation which has a cost of O(N^2 log_2 N) using the fast Fourier transform (FFT). However, …

A Language For Inconsistency-Tolerant Ontology Mapping, Kunal Sengupta

Browse all Theses and Dissertations

Ontology alignment plays a key role in enabling interoperability among various data sources present in the web. The nature of the world is such, that the same concepts differ in meaning, often so slightly, which makes it difficult to relate these concepts. It is the omni-present heterogeneity that is at the core of the web. The research work presented in this dissertation, is driven by the goal of providing a robust ontology alignment language for the semantic web, as we show that description logics based alignment languages are not suitable for aligning ontologies.

The adoption of the semantic web technologies …

Wading Bird Food Availability In Rice Fields And Crawfish Ponds Of The Chenier Plain Of Southwest Louisiana And Southeast Texas, Cullen C. Foley

LSU Master's Theses

Wading birds in southwestern Louisiana and southeastern Texas rely heavily on rice fields and crawfish ponds as foraging areas; however, little information exists on food availability throughout the annual crop cycle. The objectives of this study are: 1) Develop a classification for rice and crawfish fields based upon tillage, forage crop (for crawfish fields), water depths, vegetation density, vegetation height, and other visible parameters; 2) Quantify the distribution of rice and crawfish fields in various stages across the landscape through time; 3) Determine the effects of rice and crawfish field types and landscape characteristics on wading bird use; and, 4) …

Otoliths Then And Now: A Study Of Ancient And Modern Fish Populations In Louisiana's Coastal Waters, Marshall James Kormanec

LSU Master's Theses

Fish otoliths are composed of inorganic calcium carbonate that aid in gravity and auditory reception. Substances permanently accrete to otolith surfaces in distinct temporal patterns of alternating opaque and translucent rings; these rings are direct proxies for a fish’s age. The objective of my research is to demonstrate how otoliths can be used through time and space to estimate both age and growth of fish. I investigated the spatial differences in age distributions and growth models for red snapper, Lutjanus campechanus, at four natural shelf-edge reefs in the northwestern Gulf of Mexico. Red snapper cohorts ranged 1987-2010 cohorts, with the …

Ecological Drivers And Habitat Associations Of Estuarine Bivalves, C. Seabird Mckeon, Björn G. Tunberg, Cora A. Johnston, Daniel J. Barshis

Biological Sciences Faculty Publications

Community composition of the infaunal bivalve fauna of the St. Lucie Estuary and southern Indian River Lagoon, eastern Florida was sampled quarterly for 10 years as part of a long-term benthic monitoring program. A total of 38,514 bivalves of 137 taxa were collected and identified. We utilized this data, along with sediment samples and environmental measurements gathered concurrently, to assess the community composition, distribution, and ecological drivers of the infaunal bivalves of this estuary system. Salinity had the strongest influence on bivalve assemblage across the 15 sites, superseding the influences of sediment type, water turbidity, temperature and other environmental parameters. …

A Popular And Potentially Sustainable Fishery Resource Under Pressure-Extinction Risk And Conservation Of Brazilian Sciaenidae (Teleostei: Perciformes), Ning L. Chao, Flávia L. Frédou, Manuel Haimovici, Monica B. Peres, Beth Polidoro, Marcelo Raseira, Rosana Subira, Kent E. Carpenter

Biological Sciences Faculty Publications

Croakers (Sciaenidae) are major fishery resource in Brazil; constituting 22% of marine and 9% of freshwater fishery landings. Croakers are subject to heavy fishing pressure throughout Brazil, but habitat alteration is also an important threat to regional populations. In this regional Sciaenidae assessment, each species was analyzed for relative risk of extinction, including the identification and quantification of the impact of major threats and existing conservation measures, based on application of the Categories and Criteria of the IUCN Red List of Threatened Species. Of the 52 species of Sciaenid fishes (34 marine and 18 freshwater) present in Brazilian waters, the …

Teacher Influence On Elementary School Students’ Participation In Science, Technology, Engineering, And Mathematics, Courtney Hartman

Honors College Theses

The purpose of this study is to explore the influence of elementary school teachers on encouraging students’ interest and participation in Science, Technology, Engineering, and Mathematics. The researcher sought to understand what methods teachers use in their classrooms to encourage students to participate in STEM subjects and programs. This mixed methods study consisted of a questionnaire to collect quantitative data, as well as an interview of selected teachers who participated in the questionnaire to collect qualitative data. The data was analyzed to determine the overall perceptions of teachers regarding the importance of encouraging students to participate in STEM. The qualitative …

Communication Constructs That Influence Information Technology Project Failure, Vanessa Lajuan Ruth Mackey

Walden Dissertations and Doctoral Studies

Ineffective communication behavioral constructs in the workplace that lead to information technology (IT) project failure and in some cases organization failure are increasingly becoming a management concern. Despite this trend, there is little research on the communication behavioral constructs that contribute to IT project failure rates. The purpose of this phenomenological study was to explore the lived experiences of business analysts, programmers, and programmer analysts pertaining to the behavioral constructs associated with effective and ineffective communication. The research questions addressed these behaviors from a conceptual framework based on communication theory, organizational information processing theory, and critical social theory. This framework …

A Meta-Analysis Of Association Between One-Carbon Metabolism Gene Polymorphisms And Risk Of Prostate Cancer, Mahmood Tazari

Walden Dissertations and Doctoral Studies

Prostate cancer is the most common cancer among men. The purpose of this quantitative, meta-analysis study was to examine one-carbon metabolism gene polymorphisms in a group of genes to determine their association with prostate cancer risk. The genetic epidemiology theory provided the framework for the study. The data collected were from published articles. From over 2,800 individual studies, 20 articles were retained for results and data abstraction, following the title, abstract screen, and full text screening in the second phase. The data were analyzed by a meta-analysis statistical method, combining the results from selected studies to estimate the overall association. …

Enhancing Workplace Productivity And Competitiveness In Trinidad And Tobago Through Ict Adoption, Kennedy Jerome Swaratsingh

Walden Dissertations and Doctoral Studies

The productivity of Trinidad and Tobago's public sector workplaces is related to their absorptive capacity for technological adoption. Guided by the technology acceptance model, which suggests that individuals' and institutions' use of technology increases in relation to perceived ease of use and apparent value, this case study explored how Trinidad and Tobago used information and communications technology from 2001 - 2010 to improve public sector workplace productivity. Study data were collected from 22 individual interviews with senior executives from the government of Trinidad and Tobago, members of the e-business roundtable, and local industry experts, and from reviewing the archives of …

Effects Of Investor Sentiment Using Social Media On Corporate Financial Distress, Tarek Hoteit

Walden Dissertations and Doctoral Studies

The mainstream quantitative models in the finance literature have been ineffective in detecting possible bankruptcies during the 2007 to 2009 financial crisis. Coinciding with the same period, various researchers suggested that sentiments in social media can predict future events. The purpose of the study was to examine the relationship between investor sentiment within the social media and the financial distress of firms Grounded on the social amplification of risk framework that shows the media as an amplified channel for risk events, the central hypothesis of the study was that investor sentiments in the social media could predict t he level …

Diffusion Of Electronic Health Records In Rural Primary Care Clinics, Patricia Lynn Mason

Walden Dissertations and Doctoral Studies

By the end of 2015, Medicare-eligible physicians at primary care practices (PCP) who do not use an electronic health record (EHR) system will incur stiff penalties if they fail to meet the deadline for using EHRs. Yet, less than 30% of rural primary clinics have fully functional EHR systems. The purpose of this phenomenology study was to explore rural primary care physicians and physician assistants' experiences regarding overcoming barriers to implementing EHRs. Complex adaptive systems formed the conceptual framework for this study. Data were collected through face-to-face interviews with a purposeful sample of 21 physicians and physician assistants across 2 …

Factors Affecting Emergency Manager, First Responder, And Citizen Disaster Preparedness, Tiffany Cooks

Walden Dissertations and Doctoral Studies

Despite the increased frequency of natural and man-made disasters, there is a problem in the level of preparedness of emergency managers, responders, and citizens to address them. The purpose of this grounded theory study was to explore the factors that affect these groups' preparedness to inform the development of better emergency plans to handle emergency incidences. The conceptual framework for the study was knowledge management, which was used with a grounded theory approach. The study was guided by primary research questions that focused on understanding psychological, material, temporal, organizational, and other factors that affect the preparedness of emergency managers, first …

Financial Performance Outcomes Following System Replacement In The Insurance Industry, Trevor James Owen

Walden Dissertations and Doctoral Studies

Enterprise system replacement projects within the property and casualty insurance industry are costly, high-risk undertakings that carry a significant risk of project failure. The decision to replace policy administration systems for companies with over $250 million in direct written premium is a multimillion dollar investment for corporate strategic decision makers. This study examined the financial impact of enterprise policy administration system replacement in the property and casualty insurance industry by comparing financial performance results for companies that performed policy administration system replacements with those that did not. Insurance industry financial results for the years 2009 through 2014 were used for …

The Lived Experiences Of Limited English Proficiency, Spanish-Speaking Male Ex-Offenders, Paula Nery Sanchez

Walden Dissertations and Doctoral Studies

The purpose of this phenomenological study was to explore the lived experiences of Spanish-speaking men in the United States with limited English proficiency following their release from prison. The study specifically examined the experiences of these men in their efforts to access health care treatment, housing, education, and employment in Central Pennsylvania. An empirical, phenomenological research design was employed that used self-stigma, critical race, and self-determination theories for in-depth interviews with 8 men who spent 5 to 24 years in prison. A tiered coding method was used to generate 6 interconnected themes that tell the story of these men's lives: …

A Correlation Of Community College Math Readiness And Student Success, Jayna Nicole Brown

Walden Dissertations and Doctoral Studies

Although traditional college students are more prepared for college-level math based on college admissions tests, little data have been collected on nontraditional adult learners. The purpose of this study was to investigate relationships between math placement tests and community college students' success in math courses and persistence to degree or certificate completion. Guided by Tinto's theory of departure and student retention, the research questions addressed relationships and predictability of math Computer-adaptive Placement Assessment and Support System (COMPASS) test scores and students' performance in math courses, persistence in college, and degree completion. After conducting correlation and regression analyses, no significant relationships …