Digital Commons Network^™

Experimental And Numerical Study Of The Stirling Engine Robust Foil Regenerator, Koji Yanaga

Graduate Theses, Dissertations, and Problem Reports (ETD)

The regenerator is located between the heat accepter and the heat rejecter of the Stirling engine. It works as a thermal energy storage component in the engine. Most of the regenerators are made of woven screen or random fiber. However, the flow going through the woven screen or random fiber is similar to the cylinders in crossflow which has flow separation. To achieve higher engine efficiency, it is required to design a regenerator which has higher convective heat transfer, lower pressure drops. Therefore, a parallel channel regenerator called a robust foil regenerator was designed and manufactured.

In this study, a …

Energy Efficiency Evaluation Of Blower Heater Non-Purge Compressed Air Dryers, Alexandra M. Botts

Graduate Theses, Dissertations, and Problem Reports (ETD)

There are several compressed air dryers available for industrial use including, refrigerant, desiccant, and membrane. This research focuses on twin tower regenerative closed loop desiccant dryers, specifically: blower heater non-purge (BHNP) with and without cooling water pumps, Compressed-air Heater Purge (CHP), Blower Heater Purge (BHP), and Pressure Swing Heaterless (PSH). These styles of dryers are used mainly in industries that require extremely dry air such as, food manufacturing, medical air, or sensitive technology manufacturers. The research was conducted by collecting and analyzing real time current draw data on air compressors and associated dryers at eight different facilities (13 compressor systems) …

Autonomous Systems With Reuse: A Survey On The State-Of-The-Practice, Denny Laverne Hood Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

This problem report presents the results of an anonymous online survey that was used to collect information about software systems that use model-based software engineering, contain autonomy and where software reuse plays an important role. Recent advancements in computation ability and the emergence of decision-making algorithms have increased interest in and use of autonomy in applications areas such as aeronautics, automotive, military, and space industries. In these application domains, autonomy is used to reduce costs, reduce reaction times, and improve performance. Due to the emerging nature of autonomy, very little research has been done regarding the level of autonomy of …

Artificial Immune System For Unmanned Aerial Vehicle Abnormal Condition Detection And Identification, Ryan G. Mclaughlin

Graduate Theses, Dissertations, and Problem Reports (ETD)

A detection and identification scheme for abnormal conditions was developed for an unmanned aerial vehicle (UAV) based on the artificial immune system (AIS) paradigm. This technique involves establishing a body of data to represent normal conditions referred to as “self” and differentiating these conditions from abnormal conditions, referred to as “non-self”. Data collected from simulation of the UAV attempting to autonomously fly a pre-decided trajectory were used to develop and test a scheme that was able to detect and identify aircraft sensor and actuator faults. These faults included aerodynamic control surface locks and damages and angular rate sensor biases. The …

Evaluation And Understandability Of Face Image Quality Assessment, Mohammad I. Nouyed

Graduate Theses, Dissertations, and Problem Reports (ETD)

Face image quality assessment (FIQA) has been an area of interest to researchers as a way to improve the face recognition accuracy. By filtering out the low quality images we can reduce various difficulties faced in unconstrained face recognition, such as, failure in face or facial landmark detection or low presence of useful facial information. In last decade or so, researchers have proposed different methods to assess the face image quality, spanning from fusion of quality measures to using learning based methods. Different approaches have their own strength and weaknesses. But, it is hard to perform a comparative assessment of …

Three Essays On Water Economics, Fahad Alzahrani

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation consists of three essays that explore the impacts of changes in public water quality, reliability, and raw water source. The first essay explores the relationship between episodes of contaminated drinking water and health care expenditures in the United States. Using panel data from 48 contiguous states from 2000 to 2011 and spatial econometrics modeling methods, the results indicate that there is positive and statistically significant impact on per capita health care expenditures from the percentage of a state’s population exposed to contamination episodes. The second essay examines the problem of water supply reliability due to aging infrastructure of …

Critical Physicochemical Properties For Nanoparticle Toxicity: Impact Of Surface Coating And Size On Particle-Induced Cell Transformation And Inflammatory Response, Tiffany Kornberg

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanoparticles, which measure 100 nm in at least one dimension, have surged in development, production, and use for a wide range of applications. However, the rapid pace of development for these emerging materials with unclear/unknown toxicity profiles makes it difficult to adequately assess health risk associated with exposure. One critical obstacle which limits scientific research to fill these critical knowledge gaps is the lack of accurate and predictive models for nanotoxicology studies, particularly those which involve occupationally relevant exposure scenarios (pulmonary exposure to low dose of particles in the circulating air). Typically, animal models are used to assess potential systemic …

Investigation And Development Of Exhaust Flow Rate Estimation Methodologies For Heavy-Duty Vehicles, Chakradhar Reddy Vardhireddy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Exhaust gas flow rate from a vehicle tailpipe has a great influence on emission mass rate calculations, as the emission fractions of individual gases in the exhaust are calculated by using the measured exhaust flow rate. The development of high-end sensor technologies and emission pollutant measurement instruments, which can give instantaneous values of volume concentration of pollutants flowing out of the engine are gaining importance because of their ease of operation. The volume concentrations measured can then be used with the instantaneous exhaust flow rate values to obtain mass flow rates of pollutants.

With the recent promulgation of real world …

Chemometric Calibration Of Surface Enchanced Raman Spectra For Quantitative Analysis, Xiaofei Shi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Raman spectroscopy, recognized as a powerful analytical technique, has been widely employed in many fields especially in the detection of hazard material containing in food or water. However, multiplexed analyte quantification based on Raman spectra remains a challenge due to the difficulties in accurate and precise modeling of the relationship between multiple analyte concentrations and dense spectral data with noise.

In this work, a statistical procedure was developed to efficiently generate high-quality calibration models quantifying the analyte concentrations versus spectra relationship. The resulting calibration models are able to provide estimated concentration ranges (which reflect both point and uncertainty estimates) for …

Persistence Of Undergraduate Women In Stem Through Timsi, Heather L. Henderson

Graduate Theses, Dissertations, and Problem Reports (ETD)

There is a need to increase the persistence of women in science careers. This study focuses on undergraduate women majoring in or interested in science. Despite interest early on in their academic careers, women are leaving STEM at higher rates than other fields. Through the framework of the Tripartite Integration Model of Social Influence (TIMSI), this study explores psychosocial factors leading to integration in science careers. 484 undergraduate women from 9 universities in the Colorado/Wyoming Front Range and the Carolinas were recruited into this study and surveyed through 8 waves of data collection. A model building process was performed using …

Exsolved Nanoparticle Decorated Redox Stable Ceramic Anode Material With High Performance For Solid Oxide Fuel Cells, He Qi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The solid oxide fuel cell (SOFC) is an efficient high-temperature device that can directly convert chemical energy to electrical energy. Because of its high efficiency and environmental friendliness, extensive investigations have been made worldwide in past decades. Though broadly used as the anode material for Solid-Oxide Fuel Cells, Ni-YSZ is limited in some practical applications by severe carbon deposition on Ni in hydrocarbon fuels and a significant volume change of Ni-NiO among redox cycling. In order to overcome these problems and achieve excellent performance in the redox environment, a Ni-free ceramic material La_0.5Sr_1.5Fe_1.5Mo_{0.5 …}

Identity Formation Of Adolescents Who Are Homeschooled: Mothers' Perceptions, Peggy Joan Mcqueen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Homeschooling is a growing educational choice with very little research about the psycho-social outcomes associated with the process. This qualitative study sought to examine the potential facilitative benefit of homeschooling upon the formation of identity. The participants were 26 mothers of homeschooled adolescents in Pennsylvania. Parent responses were examined using thematic analysis. Constituent aspects of parental motivation and methodology were investigated to assess the presence of elements facilitative in the process of identity formation as identified by Erik Erikson (1959, 1963). In examining methods used in homeschooling, it was found that the mothers in this study are providing the support …

Lignocellulosic Biomass Derived Activated Carbon For Energy Storage And Adsorption, Changle Jiang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Lignocellulosic biomass has been converted to hierarchical porous carbon materials which possess macro-, meso- and micro-pores. The natural structure of porous lignocellulosic structure was preserved during activation with further developed porosity by the activation. The activated carbon can be well applied to electrochemical double layer capacitor for transportation storage of ions as well as adsorbent materials for metal ion removal from wastewater.

The first chapter of this dissertation presents an introduction of biomass derived carbon and its applications. In the second chapter, both direct and indirect activation methods using carbon dioxide were adopted in this study. The results show that …

Assessment Of Fracture Resistance Of Maxillary First Molars After Root Canal Preparation Using Three Different Rotary Instruments (V-Taper, Protaper, Vortex Blue): Finite Element Analysis, Mehran Malakpour

Graduate Theses, Dissertations, and Problem Reports (ETD)

Introduction: Long term success of endodontically treated teeth has been one of the most challenging aspects of the field of endodontics due to reduced fracture resistance of these teeth. Recently, researchers have heightened focus on conservative endodontics in order to sustain the tooth integrity, and reduce factors impacting the fracture resistance of endodontically treated teeth. As a result, rotary instrument manufacturers have developed files that have a minimal effect on original root canal anatomy. This study used Finite Element Analysis to investigate the dental biomechanical effect of rotary instrumentation during root canal therapy. The aim of this study is to …

Recovery Of Rare Earth Elements (Rees) From Coal Mine Drainage Sludge Leachate, Panpan Ren

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid mine drainage (AMD) is the primary cause of aquatic habitat loss in the Appalachian Coal Basin and many other mining districts across the U.S. and the world. The objective of this work is to develop a cost-effective and environmentally benign process to treat and recover Rare Earth Elements (REEs) from AMD. Solvent extraction (SX) is one effective way to turn AMD into a commercially viable feedstock for rare earth production.

In this work, SX experiments were conducted on Y-Ca-Mg-Al-HDEHP-n-heptane-HNO3-H2O system to simulate AMD treatment for Yttrium recovery by changing four parameters: pH values, concentration ratio of Yttrium (Y) over …

Induction Of Cerebral Hyperexcitability By Peripheral Viral Challenge: Role Of Cxcl10 Chemokine, Tiffany J. Petrisko

Graduate Theses, Dissertations, and Problem Reports (ETD)

Peripheral viral infections are po­tent comorbid factors that exacerbate neuro­degene­ration. Although the under­lying mecha­nisms have not been defined, neuronal hyperexcitability has been established as an underlying feature. Our lab has developed a preclinical model in which a viral mimetic, poly­inosinic-poly­cytidylic acid (PIC) is injected in­tra­peritoneally to induce an anti-viral acute phase response (APR). APR in turn elicits robust neuronal hyperexcitability. The present study was undertaken to characterize molecular mechanisms that mediate the development of hyperexcitability in response to PIC challenge. The analysis of brain tissue after PIC challenge revealed a robust elevation of CXCL10 chemokine, indicating its putative role in …

Music Technology, Gender, And Sexuality: Case Studies Of Women And Queer Electroacoustic Music Composers, Justin Thomas Massey

Graduate Theses, Dissertations, and Problem Reports (ETD)

This document aims to contribute to the established scholarship that highlights the role gender and sexuality has with one’s fundamental relationship to composition and music technology. The profession of electronic music composition and music production are strongly associated with notions of power and control, as much of this technology was built during the World Wars and Cold War. These aggressive views have created gendered language and metaphors in the field. Metaphors are the primary way in which we accommodate and assimilate information and experience to our conceptual organization of the world. It is at the source of our capacity to …

Design And Implementation Of Overcurrent Protection Relays Test Bench, Khalid Daud Khattak

Graduate Theses, Dissertations, and Problem Reports (ETD)

The electrical power simulator in Engineering Sciences Building (ESB) at WVU was dismantled in July 2018. The simulator was used as a teaching tool for EE students to conduct lab experiments. The power simulator employed electromechanical and microprocessor protection relays, manual isolation and industrial circuit breakers, switches, variable autotransformer (VARIAC), voltmeters and ammeters. During the dismantling, a lot of equipment was retrieved for future possible use. This led to the idea of designing and implementing a simple circuit on a test bench that can be used as a lab equipment to demonstrate the operation of overcurrent protection relays. It was …

Multidimensional Analysis Of Vulnerability: Methodological Advances And A Case Study From Malawi., Park Mcmillan Muhonda

Graduate Theses, Dissertations, and Problem Reports (ETD)

Since 1990s rural households in Malawi, constituting 85% of the population, have experienced deepening livelihood vulnerability, often manifested as persistent food insecurity. Livelihood crises have since been blamed on or attributed directly to weather perturbations/climatic shocks i.e. El-Nino induced climate variability/drought conditions. This study revealed that persistent livelihood crisis in rural Malawi cannot be attributed to or squarely blamed on weather shocks alone, rather it is at the intersection of various livelihoods shocks that rural livelihood vulnerability in Malawi is exacerbated i.e. worsening and deepening.

Thus, rural livelihood vulnerability to climate shocks in Malawi is manifest not in isolation but …

Behavioral Impairment Following Gestational Exposure To Titanium Dioxide Nanomaterial Aerosols In Male And Female Rats, Matthew Leland Eckard

Graduate Theses, Dissertations, and Problem Reports (ETD)

Engineered nanomaterials (ENMs) are beginning to be recognized as hazardous to human and animal health. Titanium dioxide (TiO2) is primarily used as a whitening agent in paints, plastics, and sunscreens. While relatively inert in its bulk form, nano-TiO2 (diameter) can produce prolonged inflammation and oxidative stress in target tissue. Recently, the potential for nano-TiO2 to cause neuroinflammation and damage has heightened concerns about its continued use. One important concern is that nano-TiO2, and other metal oxide ENMs, may affect fetal neurodevelopment. Accordingly, it is imperative to screen ENMs, like TiO2, for possible neurotoxicity following developmental exposures. The current set of …

Folk-Song To Formal Performance: Interpreting The Songs Of Jean Ritchie For Voice Recital, Julianne E. Laird

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to identify the value of incorporating American folk-song into a formal voice recital program, specifically the collections and compositions of Jean Ritchie. This qualitative study identified criteria for choosing specific folk-songs to include in formal recital, assessed quality in a folk-song arrangement, discussed suitable instrumentation for accompaniment, and suggested appropriate performance practices for concert performance. New folk-song literature was discovered through accessing original unpublished sources in the American Folklife Center of the Library of Congress. Finally, a format and program for incorporating the collected and composed folk-songs of Jean Ritchie in formal recital was …

Roadnet: Robust Adaptive Network For Information Diffusion In Vanet, Priyashraba Misra

Graduate Theses, Dissertations, and Problem Reports (ETD)

The automotive industry has changed more in the last one decade than ever before. Rapid advancements in autonomous driving have opened up opportunities for CAVs (Connected and Automated Vehicles). Vehicles today rely on a sensor-suite to map the surrounding and use that information for safety and navigation. The sensor's view is limited to its line of sight and this drawback can be tapered off by using Vehicle to Vehicle (V2V) and Vehicle to Infrastructure (V2I), generally referred to as Vehicle to Everything (V2X) communication. In this thesis, we specifically focus on utilizing V2V communication using on-board Dedicated Short Range Communication …

Engineering Plasmonic Nanostructures For Light Management And Sensing, Sujan Phani Kumar Kasani

Graduate Theses, Dissertations, and Problem Reports (ETD)

The two major global problems are to provide health safety and to meet energy demands for ever growing population on a large scale. The study of light interaction with nanostructures has shown a promising solution in improving the fields of bio-sensor and solar energy devices which addresses above mentioned two major global problems. Nanostructures have tunable physicochemical properties such as light absorption, electrical and thermal properties unlike bulk materials, which gives an advantage in applications like bio-sensing and energy harvesting devices. The development of nanofabrication techniques along with the discovery of Surface Enhanced Raman Scattering (SERS) and Plasmon Enhanced Fluorescence …

Resilient Stochastic Control Strategies In Cyber-Physical Microgrids, Mohammad Reza Khalghani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microgrids are the integration of a large number of distributed energy resources in a decentralized way such that the energy supply reliability and resiliency are enhanced against natural disasters, physical and cyber disruptions. This dissertation addresses three main challenges for microgrid operation and management:

1) According to fast growing number of Electric Vehicles (EV) deployment, their impacts on microgrids resulted from their uncertain behaviors are new concerns for the microgrid operators. These concerns can be EV charging and discharging schedule and locations of EV parking-lots in the system which are considered and solved using stochastic modeling and optimization algorithms based …

Making Armenian Politically Exposed Persons’ Money Public: A Data-Driven Journalism Project That Aims To Create A Database Of Armenian Mps’ Assets, Ani Hovhannisyan

Graduate Theses, Dissertations, and Problem Reports (ETD)

This data-driven journalism project tackles an age-old problem that seems common in virtually every government around the world: governmental officials hiding assets. By applying the theory of social responsibility, this paper uses data-journalism methods to trace the full financial assets of Armenian members of parliament and eventually making those assets and income declarations available via an interactive website to the Armenian public as well as other journalists throughout the country and region.

Bacterial Contamination Study Of Loose-Fitting Power Air Purifying Respirators (Papr) Compared To N-95 Ffr And Surgical Mask, In A Simulated Sterile Environment, Tyler J. Church

Graduate Theses, Dissertations, and Problem Reports (ETD)

Powered air purifying respirators (PAPRs) are commonly used in a health care setting, providing a higher level of protection than traditional surgical masks or N-95’s. However, little can be found in literature about their use in a sterile environment, such as an operating room. Thus, this study aims to compare bacterial contamination of three different models of PAPRs (3M^TM Versaflo^TM TR-600-ECK, 3M^TM Air-Mate^TM, and MAXAIR CAPR 710) to a N-95, surgical N-95 and surgical mask. The experiments were conducted in a small room with no ventilation, under two conditions, door open and door closed. Each …

West Virginia University’S Changing Mission In The 21st Century, Katlin Swisher

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the midst of the ongoing shifts of the perception of higher education and the public’s question of the role and value of public universities, West Virginia University has simultaneously experienced institutional change through five different presidential administrations in a decade. As seen through WVU’s historical context as the state of West Virginia’s land-grant, flagship, research university, the institution has and continues to face many administrative, policy, and contextual changes as it strives to meet its strategic goals and operationalize its mission. Through document analysis and interviews with key officials, this qualitative, multi-case study seeks to understand how WVU’s mission …

Three Essays On The Economics Of Public Libraries, Amir Borges Ferreira Neto

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation explores empirical issues concerning public libraries in the United States. In particular, it analyzes the direct and indirect effects to and from public libraries, on different issues such as charitable donations, labor market outcomes, institutions and technical efficiency. Chapter 1 discusses the economics of public libraries and its relevance. In addition, it provides an outline of the dissertation and its main contribution to the literature. Chapter 2, analyzes the determinants of donations to public libraries testing the crowding effect from government funding of public libraries. I find suggestive results of a crowd in effect with an inverted U …

Using Social Media To Combat Opioid Epidemic, Yiming Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Opioid addiction has become one of the largest and deadliest epidemics in the United States. To combat such deadly epidemic, there is an urgent need for novel tools and methodologies to gain new insights into the behavioral processes of opioid abuse and addiction. The role of social media in biomedical knowledge mining has turned into increasingly significant in recent years. The data from social media may contribute information beyond the knowledge of domain professionals (e.g., psychiatrists and epidemics researchers) and could potentially assist in sharpening our understanding toward the behavioral process of opioid addiction and treatment.

In this thesis, we …

Experimental Measurement Of Dielectric Properties Of Powdery Materials Using A Coaxial Transmission Line, Robert Tempke

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study proposes a standard methodology for coaxial dielectric property measurements of powdery materials (1-10GHz) using a coaxial transmission line. Four powdery materials with dielectric constants ranging from 3.5 to 70 (SiO2, Al2O3, CeO2, and TiO2) were experimentally investigated at varying volume loading fractions in a paraffin mixture. A statistically significant number of paraffin heterogeneous-mixtures was synthesized for all dielectric powders. The dielectric properties of the constitutive materials were determined using appropriate mixture equations. The sensitivity of the equations dielectric prediction to volume loading is discussed with guidance on selecting the best mixing equation. It was determined that low volume …