Engineering Commons^™

Identification Of The Zinc-Oxygen Divacancy In Zno Crystals, Maurio S. Holston, Eric M. Golden, Brant E. Kananen, John W. Mcclory, Nancy C. Giles, Larry E. Halliburton

Faculty Publications

An electron paramagnetic resonance (EPR) spectrum in neutron-irradiated ZnO crystals is assigned to the zinc-oxygen divacancy. These divacancies are observed in the bulk of both hydrothermally grown and seeded-chemical-vapor-transport-grown crystals after irradiations with fast neutrons. Neutral nonparamagnetic complexes consisting of adjacent zinc and oxygen vacancies are formed during the irradiation. Subsequent illumination below ∼150 K with 442 nm laser light converts these (V²⁻_Zn − V²⁺_O)⁰ defects to their EPR-active state (V⁻_Zn − V²⁺_O)⁺ as electrons are transferred to donors. The resulting photoinduced S = 1/2 spectrum of the …

Numerical Analysis For The Hemodynamics In Unruptured Cerebral Aneurysms, Hashem Mhd Hicham Alargha

Theses

A cerebral aneurysm is a vascular disorder characterized by abnormal focal dilation of a brain artery which is considered as a serious and potentially life-threatening condition. Cerebral aneurysms affect around 2%-5% of adults and they are fatal and can rupture with an overall mortality rate of more than 50%. Through computational fluid dynamics investigation, this study is offering a closer look into the initiation growth and rupture of cerebral aneurysms. Four focus points are studied in this thesis which are sensitivity analysis of blood viscosity in aneurysms, the effect of cerebral aneurysm size on wall stresses and strain, hazard effects …

Thermal Analysis For The Purpose Of Fault Diagnosis Of Commercial Proton Exchange Membrane Fuel Cells (Pemfc), Reem Izzeldin Elsadig Salim

Theses

The world's awareness towards the amount of destruction that our extensive and ignorant lifestyles in the past few decades have imposed on the environment is growing day after day. This resulted in an increased governmental and research interest towards the development and use of green technology. Fuel Cells are one of the green technologies that received a major share of research interest in the past decade.

However, despite their promising features, Fuel Cell systems still lack a solid fault diagnosis and predictive maintenance study. There are numerous faults that have to be detected and diagnosed on a fuel cell power …

Dual-Server Public-Key Encryption With Keyword Search For Secure Cloud Storage, Rongmao Chen, Yi Mu, Guomin Yang, Fuchun Guo, Xiaofen Wang

Research Collection School Of Computing and Information Systems

Searchable encryption is of increasing interest for protecting the data privacy in secure searchable cloud storage. In this paper, we investigate the security of a well-known cryptographic primitive, namely, public key encryption with keyword search (PEKS) which is very useful in many applications of cloud storage. Unfortunately, it has been shown that the traditional PEKS framework suffers from an inherent insecurity called inside keyword guessing attack (KGA) launched by the malicious server. To address this security vulnerability, we propose a new PEKS framework named dual-server PEKS (DS-PEKS). As another main contribution, we define a new variant of the smooth projective …

Notes On Contributions To The Science Of Rare Earth Element Enrichment In Coal And Coal Combustion Byproducts, James C. Hower, Evan J. Granite, David B. Mayfield, Ari S. Lewis, Robert B. Finkelman

Center for Applied Energy Research Faculty and Staff Publications

Coal and coal combustion byproducts can have significant concentrations of lanthanides (rare earth elements). Rare earths are vital in the production of modern electronics and optics, among other uses. Enrichment in coals may have been a function of a number of processes, with contributions from volcanic ash falls being among the most significant mechanisms. In this paper, we discuss some of the important coal-based deposits in China and the US and critique classification systems used to evaluate the relative value of the rare earth concentrations and the distribution of the elements within the coals and coal combustion byproducts.

Ensemble Forecasts: Probabilistic Seasonal Forecasts Based On A Model Ensemble, Hannah Aizenman, Michael D. Grossberg, Nir Y. Krakauer, Irina Gladkova

Publications and Research

Ensembles of general circulation model (GCM) integrations yield predictions for meteorological conditions in future months. Such predictions have implicit uncertainty resulting from model structure, parameter uncertainty, and fundamental randomness in the physical system. In this work, we build probabilistic models for long-term forecasts that include the GCM ensemble values as inputs but incorporate statistical correction of GCM biases and different treatments of uncertainty. Specifically, we present, and evaluate against observations, several versions of a probabilistic forecast for gridded air temperature 1 month ahead based on ensemble members of the National Centers for Environmental Prediction (NCEP) Climate Forecast System Version 2 …

The Impact Of Damage Accumulation On The Kinetics Of Network Strength Recovery For A Physical Polymer Gel Subjected To Shear Deformation, Travis Thornell, Krithika Subramaniam, Kendra Erk

School of Materials Engineering Faculty Publications

Shear rheophysical experiments were used to quantify the kinetics of strength recovery of model thermoreversible polymer gels that were fractured and ultimately sheared to different total magnitudes of strain (700 and 4000%) before resting for set periods of time. Relationships between the amount of strength recovered and the normalized ratio of resting times to characteristic relaxation times were developed. It was found that gels displayed fully healed networks within timescales that were 2-3 orders of magnitude greater than the gel’s characteristic relaxation time. Gels deformed to 700% applied strain either healed slower at lower gel concentrations as compared to experiments …

Ceramic-Ceramic Welds, Greg Hilmas, William Fahrenholtz, Jeremy Lee Watts, Derek Scott King, Sean Landwehr

Materials Science and Engineering Faculty Research & Creative Works

A method of producing a ceramic weld, including identifying a ceramic first surface an a ceramic second surface to he bonded together, maintaining a non-oxidizing atmosphere over the first and second surfaces, and engaging the first and second surfaces to define a joint, An arc is generated between an electrode and the joint to create a liquid phase, and the liquid phase is cooled to yield a solid fusion layer, wherein the first and second surfaces are joined in the fusion layer.

More Investigations In Capillary Fluidics Using A Drop Tower, Andrew Paul Wollman, Mark M. Weislogel, Brentley M. Wiles, Donald Pettit, Trevor Snyder

Mechanical and Materials Engineering Faculty Publications and Presentations

A variety of contemplative demonstrations concerning intermediate-to-large length scale capillary fluidic phenomena were made possible by the brief weightless environment of a drop tower (Wollman and Weislogel in Exp Fluids 54(4):1, 2013). In that work, capillarity-driven flows leading to unique spontaneous droplet ejections, bubble ingestions, and multiphase flows were introduced and discussed. Such efforts are continued herein. The spontaneous droplet ejection phenomena (auto-ejection) is reviewed and demonstrated on earth as well as aboard the International Space Station. This technique is then applied to novel low-g droplet combustion where soot tube structures are created in the wakes of burning drops. …

Interactive Spatiotemporal Analysis Of Oil Spills Using Comap In North Dakota, Yong Shin Park, Hamad Al-Qublan, Eunsu Lee, Gokhan Egilmez

Mechanical and Industrial Engineering Faculty Publications

The aim of the study is to analyze the oil spill pattern from various types of incidents and contaminants to determine the extent that incident data can be used as a baseline to prevent hazardous material releases and improve response activities at a state level. This study addresses the importance of collecting and sharing oil spill incidents as well as analytics using the data. Temporal, spatial and spatiotemporal analysis techniques are employed for the oil-spill related environmental incidents observed in the state of North Dakota, United States of America, from 2000 to 2014, as a result of the oil boom. …

X-Ray Absorption Spectroscopy Study Of The Effect Of Rh Doping In Sr2Iro4, C. H. Sohn, Deok-Yong Cho, C. -T. Kuo, L. J. Sandilands, Tongfei Qi, Gang Cao, T. W. Noh

Center for Advanced Materials Faculty Publications

We investigate the effect of Rh doping in Sr₂IrO₄ using X-ray absorption spectroscopy (XAS). We observed appearance of new electron-addition states with increasing Rh concentration (x in Sr₂Ir_1−xRh_xO₄) in accordance with the concept of hole doping. The intensity of the hole-induced state is however weak, suggesting weakness of charge transfer (CT) effect and Mott insulating ground states. Also, Ir J_eff = 1/2 upper Hubbard band shifts to lower energy as x increases up to x = 0.23. Combined with optical spectroscopy, these results suggest a hybridisation-related mechanism, in …

The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2016, Ven Basco

Libraries' Newsletters

No abstract provided.

Increasing 18f-Fdg Pet/Ct Capabilities In Radiotherapy For Lung And Esophageal Cancer Via Image Feature Analysis, Jasmine Alexandria Oliver

USF Tampa Graduate Theses and Dissertations

Positron Emission Tomography (PET) is an imaging modality that has become increasingly beneficial in Radiotherapy by improving treatment planning (1). PET reveals tumor volumes that are not well visualized on computed tomography CT or MRI, recognizes metastatic disease, and assesses radiotherapy treatment (1). It also reveals areas of the tumor that are more radiosensitive allowing for dose painting - a non-homogenous dose treatment across the tumor (1). However, PET is not without limitations. The quantitative unit of PET images, the Standardized Uptake Value (SUV), is affected by many factors such as reconstruction algorithm, patient weight, and tracer uptake time (2). …

Spin-Gapless Semiconductivity And Half Metallicity In Heusler Alloys, Bradley A. Staten, Pavel V. Lukashev

Research in the Capitol

In recent years, ever increasing interest in spin-based electronics (spintronics) has resulted in the search for a new class of materials that can provide a high degree of transport spin polarization. An ideal candidate would act like insulator for one spin channel and a conductor or semiconductor for the opposite spin channel (e.g. half metals (HM), spin gapless semiconductors (SGS)). In this work, we present results of our computational and theoretical study (Staten, et al., J. Appl. Phys. 117, 17D115 (2015)) of Heusler compounds with potential commercial applications in the field of spintronics. We show that naturally these materials are …

Congratulations A-Pin Recipients | College Of Engineering, Usu College Of Engineering

College of Engineering News

March 29, 2016 – Dean Christine Hailey and department heads from across the College of Engineering on Tuesday recognized 13 students for receiving the prestigious A-Pin award.

The A-Pin is one of the oldest awards at Utah State University. Initiated in 1910, it acknowledges and rewards students who achieve a straight-A grade point average while carrying 15 graded credit hours for two consecutive semesters.

Method To Fabricate Portable Electron Source Based On Nitrogen Incorporated Ultrananocrystalline Diamond (N-Uncd), Anirudha V. Sumant, Ralu Divan, Chrystian M. Posado, Carlos Henry Castano Giraldo, Edwin J. Grant, Hyoung-Koo Lee

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

A source cold cathode field emission array (FEA) source based on ultra-nanocrystalline diamond (UNCD) field emitters. This system was constructed as an alternative for detection of obscured objects and material. Depending on the geometry of the given situation a flat-panel source can be used in tomography, radiography, or tomosynthesis. Furthermore, the unit can be used as a portable electron or X-ray scanner or an integral part of an existing detection system. UNCD field emitters show great field emission output and can be deposited over large areas as the case with carbon nanotube “forest” (CNT) cathodes. Furthermore, UNCDs have better mechanical …

Highway Expenditures And Associated Customer Satisfaction: A Case Study, Alexander Paz-Cruz, H De La Fuente-Mella, A Singh, R Conover, H Monteiro

Civil and Environmental Engineering and Construction Faculty Research

This study analyzes the satisfaction of the Nevadans with respect to their highway transportation system and the corresponding expenditures of Nevada Department of Transportation (NDOT). A survey questionnaire was designed to capture the opinions of the Nevadans (customers) about a number of characteristics of their transportation system. Data from the financial data warehouse of the NDOT was used to evaluate expenditures. Multinomial probit models were estimated to study the correlations between customers' opinion and the government expenditures in transportation. The results indicate the customer satisfaction is decreasing with respect to traffic safety throughout Northwestern and Southern Nevada highways. In addition, …

Closing A Synthetic Carbon Cycle: Carbon Dioxide Conversion To Carbon Monoxide For Liquid Fuels Synthesis, Yolanda Andreina Daza

USF Tampa Graduate Theses and Dissertations

CO₂ global emissions exceed 30 Giga tonnes (Gt) per year, and the high atmospheric concentrations are detrimental to the environment. In spite of efforts to decrease emissions by sequestration (carbon capture and storage) and repurposing (use in fine chemicals synthesis and oil extraction), more than 98% of CO₂ generated is released to the atmosphere. With emissions expected to increase, transforming CO₂ to chemicals of high demand could be an alternative to decrease its atmospheric concentration. Transportation fuels represent 26% of the global energy consumption, making it an ideal end product that could match the scale of CO …

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• Dr. Mitra Accepts PLTW Award for Georgia

Optimization And Characterization Of Integrated Microfluidic Surface Acoustic Wave Sensors And Transducers, Tao Wang

USF Tampa Graduate Theses and Dissertations

Surface acoustic waves (SAWs) have a large number of applications and the majority of them are in the sensor and actuator fields targeted to satisfy market needs. Recently, researchers have focused on optimizing and improving device functions, sensitivity, power consumption, etc. However, SAW actuators and sensors still cannot replace their conventional counterparts in some mechanical and biomedical areas, such as actuators for liquid pumping under microfluidic channels and sensors for real-time cell culture monitoring. The two objectives of this dissertation are to explore the potential of piezoelectric materials and surface acoustic waves for research on actuators and sensors in the …

Poster Session, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

1. Fecal Coliforms and E. coli Levels in Surface Waters from McConnell Springs, 2011-2015, David Price, Division of Water Quality, Lexington-Fayette County Government
2. Buried Soils as an Important Control on C Storage along Human-Impacted Floodplains in Kentucky, USA, Ashley Casselberry and Gary Stinchcomb, Dept. of Geosciences & Watershed Studies Institute, Murray State University
3. Buried Soils are an Important Chemical Interface Controlling Mineral Weathering and Solute Gradients along River Corridors, Gary Stinchcomb, Ashley Casselberry, and Abigail Smith, Dept. of Geosciences & Watershed Studies Institute, Murray State University
4. Geospatial Evaluation of Sewer Gas to Indoor Air Pathways Relevant for Vapor …

Track 2: Stream Restoration, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Bankfull Open Channel Flow Model: Development and Applications for Stream Restoration Design, Charles Davis and Brian Belcher, Beaver Creek Hydrology, LLC, Lexington, KY
• Using Stream Restoration for Pollution Reduction, Wanda Lawson, Stantec Consulting Services, Inc, Louisville, KY
• KDFWR Hatchery Creek Stream and Wetlands Restoration Project - A Unique Opportunity to Maximize Trout Habitat, Create Recreational Opportunities and Provide Mitigation Credits: Planning & Design, Oakes Routt and others, Stantec Consulting Services, Inc., Louisville, KY
• KDFWR Hatchery Creek Stream and Wetlands Restoration Project - A Unique Opportunity to Maximize Trout Habitat, Create Recreational Opportunities and Provide Mitigation Credits: Construction …

Track 2: Environmental Impact, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Toward Rapid Detection of Phytophthora cinnamomi in Appalachian Streams, Kenton Sena and others, Dept. of Forestry, University of Kentucky
• Arsenic in Water and Risk of Cancer in Humans, Steven Lamm and others, Center for Epidemiology and Global Health, Washington, DC
• Examining the Impacts of Valley Fills in Stream Ecosystems on Amphibian and Aquatic Insect Communities in Southeastern Kentucky, John Bourne and Stephen Richter, Patuxent Research Refuge, Laurel, MD and Eastern Kentucky University
• The Wetlands Prioritization Tool, Caroline Chan, Kentucky Division of Water, Frankfort, KY

Track 2: Soils, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Controlled Drainage in Western Kentucky: Mitigating Water Stress and Reducing Nutrient Loss to Surface Waters in Grain Crop Production, Ethan Snyder and Carrie Knott, Dept. of Plant and Soil Sciences, University of Kentucky
• Comparing Simulated Soil Properties to Field Derived Values in Forested and Grassland Catena of MLRA 120, Trinity Baker and others, Dept. of Plant and Soil Sciences, University of Kentucky
• Soil Infiltration Rates in Six Agricultural Fields of Western Kentucky, Landon Gibbs and Iin Handayani, Dept. of Agricultural Science, Murray State University
• Investigation of the Climate Modeling Factors Impacting Forecasted Streamflow for Central Kentucky, …

Track 1: Source Water Protection, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Kentucky's Source Water Protection Assistance Program, Robert Blair and James Calhoun, Watershed Management Branch, Kentucky Division of Water and Jessica Moore, U.S. EPA, Dallas Texas
• Source Water Protection Assistance Program, Trimble County Water District #1 Customer Outreach Program, Andrew Stark, Trimble County Water District #1, Bedford, KY
• Kentucky Rural Water Association and Water Utilities' Efforts in Protecting Drinking Water Sources, Jack Stickney, Kentucky Rural Water Association, Bowling Green, KY
• Source Water Protection for the Riverbank Filtration System, Kay Ball and Rob Newman, Louisville Water Company, Louisville, KY

Track 1: Karst, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Characteristics of Cover-Collapse Sinkholes in Kentucky, James C. Currens, Kentucky Geological Survey
• Data and Model Investigation of a Fluviokarst System in the Bluegrass Region: Water, Sediment, and Carbon Interactions, Admin Husic and others, Dept. of Civil Engineering, University of Kentucky
• Sourcing and Dynamics of Karst Hydrologic Inputs on Harmful Algal Bloom Occurrences in Kentucky Lakes, Robert Schaefer and Jason Polk, Dept. of Geography and Geology, Western Kentucky University
• Investigation of Fecal Contamination in the Little River Basin, Kentucky Using Microbial Source Tracking and Fecal Indicator Bacteria, 2013-2014, Mac A. Cherry, USGS, Kentucky Water Science Center

Track 1: Groundwater, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

• Proposed Bill to License Closed-Loop Geothermal System Vertical Borehole Well Drillers, Bart Davidson, Kentucky Geological Survey, David Jackson and Scotty Robertson, Kentucky Division of Water
• Using Oil and Gas Data to Assess the Distribution of Fresh and Saline Water in Northeastern Kentucky, Ethan Davis, Kentucky Geological Survey
• A Pilot Study to Assess Baseline Groundwater Chemistry for the Berea Sandstone and Rogersville Shale Play Area, Eastern Kentucky, Junfeng Zhu and others, Kentucky Geological Survey
• Investigation of Limestone Aquifer Characteristics in the Elizabethtown, Kentucky Area, Chuck Taylor and others, Kentucky Geological Survey

Plenary Session: Working With Flint Residents: Lead Discovery And Citizen Science In The Flint Water Crisis, Min Tang

Kentucky Water Resources Annual Symposium

No abstract provided.

Proceedings Of 2016 Kentucky Water Resources Annual Symposium, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

This symposium was planned and conducted as a part of the state water resources research institute annual program that is supported by Grant/Cooperative Agreement Number G11AP20081 from the United States Geological Survey. The contents of this proceedings document and the views and conclusions presented at the symposium are solely the responsibility of the individual authors and presenters and do not necessarily represent the official views of the USGS or of the symposium organizers and sponsors. This publication is produced with the understanding that the United States Government is authorized to reproduce and distribute reprints for government purposes.

Mobile Application For Biosensor Colorimetric Analysis, Eui Bin You

Honors Theses

Inexpensive paper-based biosensors can be valuable screening tools to test for various illnesses, but it is often challenging to design them to produce a visual change that can easily be identified by untrained users. This research examines one method of compensating for the lack of distinct visual cues by developing and testing a mobile application that uses a machine learning algorithm (k-Nearest Neighbors) to analyze a picture of a sensor and determine whether it shows a positive or negative result. The machine learning algorithm was trained on a set of labeled sensor images and k-fold cross-validation was used to analyze …