Rare Earth Element Distribution In Fly Ash Derived From The Fire Clay Coal, Kentucky, Madison M. Hood, Ross K. Taggart, Ryan C. Smith, Heileen Hsu-Kim, Kevin R. Henke, Uschi Graham, John G. Groppo, Jason M. Unrine, James C. Hower

Coal Combustion and Gasification Products Journal Archive

Fly ash was collected from individual mechanical and electrostatic precipitator (ESP) hoppers at a 130-MW pulverized-coal utility unit burning a southeastern Kentucky moderate- to high-S Pennsylvanian Fire Clay coal. The fly ash particle size is generally similar within each row of the mechanical and ESP hoppers, with the mean particle diameter decreasing from >36 μmin the mechanical hoppers to 6 μm in the last ESP row. Rare earth element (REE)–bearing phases occur within fine minerals and, possibly, as part of the fly ash glass phase. Transmission electron microscopy was used to identify Y-Ce-Nd-La–bearing regions within a glassy matrix. Y- and …

The Relative Impact Framework For Evaluating Coal Combustion Residual Surface Impoundment Closure Options: Applications And Lessons Learned, Ari S. Lewis, Andrew B. Bittner

Coal Combustion and Gasification Products Journal Archive

In response to the U.S. Environmental Protection Agency’s new rule regarding the disposal of coal combustion residuals (CCRs), many utilities need to re-examine their waste disposal practices and make decisions regarding if and how unlined surface impoundments (SIs) should be closed. The two primary options for closing SIs are in-place closure, with capping and engineering controls, and excavation of the CCR for transport to and re-disposal in a lined landfill. To help inform closure option decisions, we supported the Electric Power Research Institute’s development of a practical, science-based decision framework that comprehensively evaluates the potential impacts to human health and …

Probabilistic Analysis Of Wear Of Polymer Material Used In Medical Implants, V. Perel, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Probabilistic methods are applied to the study of fatigue wear of sliding surfaces. A variance of time to failure (to occurrence of maximum allowable wear depth) is evaluated as a function of a mean wear rate of normal wear and a size of wear particles. A method of estimating probability of failure-free work during a certain time interval (reliability) is presented. An effect of the bedding-in phase of wear on the reliability is taken into account. Experimental data for Ultra High Molecular Weight Polyethylene (UHMWPE) cups of artificial hip implants is used to make numerical calculations.

Engineering Inpatient Discharges: Disposition Prediction And Day-Of-Discharge Planning, Nicholas A. Ballester

Browse all Theses and Dissertations

Inpatient discharge planning is a critical decision point in patient care, with implications for the efficiency of the inpatient unit as well as other units of the acute care hospital. Inefficient discharge planning can cause patient boarding (waiting for beds) in the upstream units. While this is a poignant and well-known problem in healthcare, very little quantitative research exists that proposes approaches to alleviate it. To address this issue, we apply Systems Engineering methods with focus on three key challenges in inpatient discharge planning. First, to aid inpatient care providers in predicting discharge disposition (home vs. non-home) within 24-hours of …

Development Of Computer Program For Wind Resource Assessment, Rotor Design And Rotor Performance, Valentina Jami

Browse all Theses and Dissertations

People understand and have seen that renewable energy has many advantages over conventional energy sources. Because of these advantages, more and more emphasis has been given to generating electrical energy with renewable sources. Among the many renewable and conventional ways currently available for a society to generate electrical power, wind turbines are one of the cheapest ways of doing this. The main objective of this thesis work is to develop a computer program that assesses the wind resource at a given location, designs a wind turbine rotor for optimum power capture for one wind speed, and analyzes the performance of …

Development Of Guidance Laws For A Reduced Order Dynamic Aircraft Model, Jack W. Brendlinger

Browse all Theses and Dissertations

A set of guidance control laws has been developed for enabling three distinct modes of operation of a reduced order dynamic aircraft model. These include 1) a waypoint following control law, 2) a trajectory tracking control law, and 3) a set of kinematically constrained control laws for reaching a commanded altitude, speed or heading. The formulation of the reduced order model is presented so that the capabilities and limitations of the model are understood, and so that the interface architecture between the controllers and the plant is clearly defined. The controller formulations are then presented, together with sample results. The …

Influential Women In Flight - Introduction, Becca Stegmann

Women in STEM

For this assignment, I created a collection of trading cards that provide biographies and important information about influential minority women in flight. The front of each card has basic demographic information, including each person’s name, birth date, hometown, and what they are known for. The back of each card has a slightly longer explanation of each person, followed by something they are quoted with saying and some key facts about their lives. The cards can be printed out in color and laminated for longevity if desired.

Lighted Ear Curette, Kelsey Ashmore, Kaitlin Klotzle, Crysta Yamamoto, Katrina Elfrink, Cynthia Stoller

Williams Honors College, Honors Research Projects

The ear canal is a sensitive and small part of the human body that is prone to accumulate cerumen or lodge foreign bodies. In order to clean the ear canal or remove foreign bodies, three hands are required: one to brace the patient's head, one to maneuver the curette that is used to clean the ear, and one to hold a light source in order to make the small, dark area visible. Therefore, a design is needed that can allow a doctor to safely clean an ear with an instrument that only requires two hands. Furthermore, the design must have …

Lean Implementation Through Process Automation, Olusola Onadipe Jr.

All Graduate Theses, Dissertations, and Other Capstone Projects

As lean manufacturing is increasingly becoming a common practice today in an effort to keep companies competitive, new and innovative processes are becoming the norm. Part of that innovation includes the development of automated machinery that can help alleviate some struggles with lead times and reduce overall labor. It is all in keeping with the trend of building products cheaper and faster to gain that edge. Company X has been focusing their efforts on lean manufacturing for years now. This paper covers an important project that involves the implementation of a complex mechanical system in an effort to build products …

Weighting Policies For Robust Unsupervised Ensemble Learning, Ramazan Unlu

Electronic Theses and Dissertations

The unsupervised ensemble learning, or consensus clustering, consists of finding the optimal com- bination strategy of individual partitions that is robust in comparison to the selection of an algorithmic clustering pool. Despite its strong properties, this approach assigns the same weight to the contribution of each clustering to the final solution. We propose a weighting policy for this problem that is based on internal clustering quality measures and compare against other modern approaches. Results on publicly available datasets show that weights can significantly improve the accuracy performance while retaining the robust properties. Since the issue of determining an appropriate number …

Spatial And Temporal Compressive Sensing For Vibration-Based Monitoring: Fundamental Studies With Beam Vibrations, Vaahini Ganesan

Electronic Theses and Dissertations

Vibration data from mechanical systems carry important information that is useful for characterization and diagnosis. Standard approaches rely on continually streaming data at a fixed sampling frequency. For applications involving continuous monitoring, such as Structural Health Monitoring (SHM), such approaches result in high data volume and require powering sensors for prolonged duration. Furthermore, adequate spatial resolution, typically involves instrumenting structures with a large array of sensors. This research shows that applying Compressive Sensing (CS) can significantly reduce both the volume of data and number of sensors in vibration monitoring applications. Random sampling and the inherent sparsity of vibration signals in …

Journal Of The Arkansas Academy Of Science- Volume 71 2017, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Restrained Shrinkage Of Fly Ash Based Geopolymer Concrete And Analysis Of Long Term Shrinkage Prediction Models, Md R. Islam, Mahbub K. Ahmed, Hosney Ara Begum, Erez N. Allouche

Journal of the Arkansas Academy of Science

The research presented in this manuscript describes the procedure to quantify the restrained shrinkage of geopolymer concrete (GPC) using ring specimen. Massive concrete structures are susceptible to shrinkage and thermal cracking. This cracking can increase the concrete permeability and decrease the strength and design life. This test is comprised of evaluating geopolymer concrete of six different mix designs including different activator solution to fly ash ratio and subjected to both restrained and free shrinkage. Test results obtained from this experimental setup was plotted along with the available empirical equation to observe the shrinkage strain of GPC and a model was …

An Acoustic-Based Approach For Condition Monitoring Of Pipes, Muhammad S. Khan, Turaj Ashuri, Mitchell Collins, Geoffrey Birkemeier, Emad Almohmmedali

Journal of the Arkansas Academy of Science

Polyvinyl chloride pipes are extensively used in municipal sewer systems. As the sewer system ages, polyvinyl chloride pipes become prone to developing cracks that can release toxic effluents into the environment. Traditionally, utility operators pass a close circuit television camera mounted on a guided vehicle through the pipe to monitor the defects. The video is observed by a trained operator who records the condition of the pipe. This arrangement has two major limitations. First, it is expensive due to complex set up. Second, if a pipe is blocked the guided vehicle cannot pass through its entire length. A more economical …

Coates Family Collection, Zach S. Henderson Library Special Collections

Finding Aids

Spanning 1988-2020, the collection highlights the life, career and personal interests of Dr. Basil L. Coates, former faculty member of Mechanical Engineering at Georgia Southern University. Materials also reference Dr. Coates’ wife and fellow faculty member, Kay G. Coates, as well as their shared travels and research.

Find this collection in the University Library's Catalog

Towards Design And Analysis For High-Performance And Reliable Ssds, Qianbin Xia

Theses and Dissertations

NAND Flash-based Solid State Disks have many attractive technical merits, such as low power consumption, light weight, shock resistance, sustainability of hotter operation regimes, and extraordinarily high performance for random read access, which makes SSDs immensely popular and be widely employed in different types of environments including portable devices, personal computers, large data centers, and distributed data systems.

However, current SSDs still suffer from several critical inherent limitations, such as the inability of in-place-update, asymmetric read and write performance, slow garbage collection processes, limited endurance, and degraded write performance with the adoption of MLC and TLC techniques. To alleviate these …

Nanomedicine Drug Delivery Across Mucous Membranes, Michael G. Lancina Iii

Theses and Dissertations

NANOMEDECINE DRUG DELIVERY ACROSS MUCOUS MEMBRANES

By Michael G. Lancina III

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University.

Virginia Commonwealth Univeristy, 2017.

Major Director: Dr. Hu Yang, Associate Professor, Chemical and Life Science Engineering

Control over the distribution of therapeutic compounds is a complex and somewhat overlooked field of pharmaceutical research. When swallowing a pill or receiving an injection, it is commonly assumed that drug will spread throughout the body in a more or less uniform concentration and find its way to wherever it is needed. In …

Growth Of Zn-Polar Bemgzno/Zno Heterostructure With Two Dimensional Electron Gas (2deg) And Fabrication Of Silver Schottky Diode On Bemgzno/Zno Heterostructure., Md Barkat Ullah

Theses and Dissertations

Title of dissertation: GROWTH OF Zn POLAR BeMgZnO/ZnO HETEROSTRUCTURE WITH TWO DIMENSIONAL ELECTRON GAS (2DEG) AND FABRICATION OF SILVER SCHOTTKY DIODE ON BeMgZnO/ZnO HETEROSTRUCTURE

By Md Barkat Ullah, Ph.D

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Electrical and Computer Engineering at Virginia Commonwealth University.

Virginia Commonwealth University,2017

Major Director: Dr. Hadis Morkoç, Professor, Electrical and Computer Engineering

This thesis focuses on growth of Zn polar BeMgZnO/ZnO heterostructure on GaN/sapphire template with two dimensional electron gas (2DEG) for the application of UV photodetector/emitter and high speed electronics. The motivation of using …

Synthesis, Characterization, And Enhanced Magnetic Properties Of Iron Carbide Nanomaterials, Brent M. Williams

Theses and Dissertations

Permanent magnets are classified as hard magnetic materials with the main purpose of generating flux for applications such as electric motors, turbines, and hard drives. High coercivity, magnetic remanence, and saturation values with high stability are some of the requirements for permanent magnets. Rare-earth magnets including neodymium and samarium based magnets are known to have superior magnetic properties due to their high magnetocrystalline anisotropy. However, due to the price of rare-earth materials development of alternate permanent magnets composed of inexpensive materials is an ongoing process. Previously cobalt carbide (Co_xC) have shown promise as a potential rare-earth free magnet …

Comparative Studies Of Diffusion Models And Artificial Neural Intelligence On Electrochemical Process Of U And Zr Dissolutions In Licl-Kcl Eutectic Salts, Samaneh Rakhshan Pouri

Theses and Dissertations

The electrorefiner (ER) is the heart of pyroprocessing technology operating at a high-temperature (723 K – 773 K) to separate uranium from Experimental Breeder Reactor-II (EBR-II) used metallic fuel. One of the most common electroanalytical methods for determining the thermodynamic and electrochemical behavior of elemental species in the eutectic molten salt LiCl-KCl inside ER is cyclic voltammetry (CV). Information from CV can possibly be used to estimate diffusion coefficients, apparent standard potentials, transfer coefficients, and numbers of electron transferred. Therefore, predicting the trace of each species from the CV method in an absence of experimental data is important for safeguarding …

Eye Movement Control: An Index For Athleticism, Brittany L. Oshea

Theses and Dissertations

Athletic potential is one of the most complex human traits. An elite athlete is produced from a complex interaction of an innumerable number of traits exhibited by the athlete. However, it’s not clear whether these traits are innate, allowing the athlete to excel, or, alternatively, are a consequence of practice. To be successful, athletes rely heavily on sensory information from the visual and vestibular systems. This study investigated the relationship eye movement control has with innate athleticism by comparing the saccadic and Vestibulo-Ocular Reflex (VOR) responses of former, no longer practicing, elite athletes against their age and gender matched counterparts …

Enhanced Energy Storage And Conversion Applications By Porous Carbon And Atomic Layer Deposition, Yomna H. Abdelmoaty

Theses and Dissertations

The design and synthesis of porous materials attracted great attention recently because of their potential use in many fields like clean energy and environmental protection. Herein, we introduced new synthetic approaches for the preparation for porous carbons and organic polymers for selective CO₂ and iodine capture application. Regarding CO₂ capture application, Two new

series of porous carbons (PYDCs) and (TRI-Ps) were synthesized by thermally activating Pyrazole and Triazolo Pyridine monomers respectively using KOH as a catalyst, which leads to porous carbon. PYDCs exhibit high surface area according to Brunauer–Emmett–Tellertheory (SA_BET = 1266–2013 m² g⁻¹), …

Robust Scale-Invariant Normalization And Similarity Measurement For Time Series Data, Ariyawat Chonbodeechalermroong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Classification is one of the most prevalent tasks in time series mining. Dynamic Time Warping and Longest Common Subsequence are well-known and widely used algorithms to measure similarity between two time series sequences using non-linear alignment. However, these algorithms work best when the time series pair has similar amplitude scaling. Unfortunately, sensor data and most real-world time series data usually contain noise, missing values, outlier, and variability or scaling in both axes, which is not suitable for the widely used Z-normalization. This research introduces the Local Feature Normalization (LFN) and its Local Scaling Feature (LSF), which can be used to …

A Tree-Based Collision Resolution Algorithm For Rfid Using Bayesian Tag Estimation, Sanika Krishnamali Wijayasekara

Chulalongkorn University Theses and Dissertations (Chula ETD)

Radio Frequency IDentification (RFID) is a promising wireless object identifying technology which uses radio frequency waves to transmit data between an RFID reader and tags. The RFID systems have been effectively applied in different areas, like manufacturing, healthcare, supply chain, transportation and agriculture. Despite the vast deployment of the RFID technology in practice, the inherent RFID tag collision problem still persists as a serious concern and remains a challenge. The tag collision problem happens when some tags in reader's vicinity try to transmit data to a reader simultaneously without priori coordination. The existing RFID Electronic Product Code (EPC) Class 1 …

Space Utilisation Strategy For Thailand Underground Transit Station. A Case Study Of Thailand Cultural Centre Underground Station, Wirasinee Tongsoo

Chulalongkorn University Theses and Dissertations (Chula ETD)

The ridership of Thailand underground station continuously increases every year. On the other hand, space management of terminal of underground station does not success as expected. The main reason is space does not have strategy to handle. majority of renter rarely stay until the completion of the rental contract, and they prefer to break the contract, pay the fine and move business elsewhere. According to research, there is no research study about this for Thailand underground station. In order to create appreciate plan for Thailand underground station in 2022. The strategy is core to integrate plan. Passengers would be attracted …

Microemulsion Formation Of Vegetable Oils Using Mixed Extended Surfactant For Cleaning Applications, Siriluk Jariyawattanarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Some vegetable oils and animal fats can form semi-solid crystalline. The formation of semi-solid fats or waxy soils results in weak interactions between the oil and surfactant during the cleaning process. In this study, the anionic extended surfac-tant (C14-15, 8PO-SO4) systems were employed to form a middle phase microemul-sion with various vegetable oils (coconut, palm and soybean oil). The addition of nonionic extended surfactant (C16-18, 2PO-4EO-OH) in the mixed surfactant systems was also evaluated to observe the solubility enhancement of oil and water phase. The IFT value of formulated surfactant systems was measured to determine the optimum salinity. The Hydrophilic-Lipophilic …

Synthesis Of Magnetic Carbon Nanoparticles Using Pyrolysis Of Glycerol And Ferrocene For Antibiotic Removal, Konrat Kerdnawee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Synthesis of magnetic carbon nanoparticles (M-CNPs) via nebulizing co-pyrolysis of glycerol and ferrocene with magnetic induction was successfully conducted. Experimental investigation on influence of synthesizing temperature and ratio of glycerol to ferrocene suggested that at 800 °C of synthesizing temperature with an initial weight ratio of glycerol to ferrocene of 3:1, the highest M-CNP synthesizing yield of 15.9 % was achieved. With the presence of magnetic induction, controlled synthesis of M-CNPs could be anticipated as a promising method for producing M-CNPs with high quality and high yield. Oxy-tetracycline (OTC) has been recognized as environmental contamination due to its over-dosage and …

Development Of Conductive Polyimide/Polysulfone Composites As Positive Temperature Coefficient Materials, Noppawat Kuengputpong

Chulalongkorn University Theses and Dissertations (Chula ETD)

For positive temperature coefficient (PTC) applications of electrically conductive composites, volume resistivity at room temperature of lower than 104 Ω.cm is one major requirement. Conductive polyimide (PI) PTC with the above level of conductivity value can be achieved by a use of carbon black (CB) as conductive filler. For materials with PTC, there is a change in resistance related to temperature. In order to reduce the amount of CB used in the PTC composites, one of well-known methods is to introduce another polymer into a polymer to generate immiscible blends. When the conductive filler is dispersed in one polymer phase, …

Workshop Synthesis: Measuring Attitudes And Perceptions In Quantitative Surveys, Kelly Clifton, Juan Antonio Carrasco

Civil and Environmental Engineering Faculty Publications and Presentations

This workshop engaged participants in discussion about issues in incorporating qualitative information, namely attitudes, perceptions, and other psychological-social factors into transport research and analysis. There are many challenges to collecting this information from respondents. This synthesis summarizes the workshop presentations and discussion where participants identified the various types of information desired, reviewed the current challenges in conducting this type of data collection, made recommendations for practice, and outlined an agenda for future research.

Development Of Self-Sensing Carbon Nanotube-Based Composites For Civil Infrastructure Applications, Thomas Schumacher, Erik T. Thostenson

Civil and Environmental Engineering Faculty Publications and Presentations

Presented at the 5th International Symposium on Sensor Science (I3S 2017), Barcelona, Spain, 27–29 September 2017.

Worldwide, civil infrastructure systems are aging and deteriorating due to maintenance neglect, increasing traffic, and an environment that is becoming increasingly more severe. In particular, bridges play a critical role in the transportation network. With limited monies available for maintenance and repair, a need exists for effective yet inexpensive solutions to strengthen and monitor bridges. This presentation provides an overview of the development of carbon nanotube (CNT)-based composites, which offer a means to strengthen and monitor a deteriorated bridge member simultaneously. CNT sensors are …