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Dynamic Property Evaluation Of Frother, Yunkai Xia
Dynamic Property Evaluation Of Frother, Yunkai Xia
Graduate Theses, Dissertations, and Problem Reports (ETD)
Fourteen solvents were evaluated through frothing test and laboratory flotation batch tests. A new frothing parameter, initial dynamic froth index (IDFI), is proposed to compare the frothability of solvent. IDFI is derived from initial retention time of froth instead of retention time. IDFI is defined as the limiting slope of the initial retention time versus concentration curves while the concentration approaches zero. IDFI value depends on chemical structure and molecular weight of the solvent. Combined with normalized frothability index (NFI), normalized collapse rate constant (NKc), hydrophilic-lipophilic balance (HLB) and dynamic froth index (DFI), IDFI can be a useful index in …
Effect Of Manufacturing Process Conditions On The Durability Of Pultruded Vinyl Ester/Glass Composites, Chrystal Ann Garland
Effect Of Manufacturing Process Conditions On The Durability Of Pultruded Vinyl Ester/Glass Composites, Chrystal Ann Garland
Graduate Theses, Dissertations, and Problem Reports (ETD)
Fiber reinforced polymer composites, FRPs, have an increased role in structural applications. Environmental durability is important for the design of structural components. Processes such as pultrusion are cost-effective methods of producing FRPs. This research focused on the durability of pultruded FRP with different processing conditions. Pultruded samples made at different line speeds (4, 8, and 12 ipm) were immersed in water at 25, 50, and 85°C for varying lengths of time and the mechanical properties evaluated via 3-point bending tests. A reduction in strength was observed for the samples immersed in 50 and 85°C water, with the largest reduction occurring …
Removal Of Uranium From Aqueous Wastes Using Electrically Charged Carbon Nanofibers, Shannon Lee Stover
Removal Of Uranium From Aqueous Wastes Using Electrically Charged Carbon Nanofibers, Shannon Lee Stover
Graduate Theses, Dissertations, and Problem Reports (ETD)
The presence of aqueous uranium wastes is a problem in the United States and their treatment/disposal is desirable. Treatment methods have been developed but result in concentration opposed to conversion to a disposable form. This technique involves recovery of uranium as a solid, providing an advantage over other methods. The technique utilizes carbon nanofibers as electrodes which successfully electrosorb uranium ions. Fibers with varying surface characteristics were evaluated in the removal process and all were determined to be equally and extremely effective. Various experimental parameters were evaluated including applied potential, pH, and flow rate. The critical applied potential at which …
Investigation And Simulation Of The Planetary Combination Hybrid Electric Vehicle, Csaba Toth-Nagy
Investigation And Simulation Of The Planetary Combination Hybrid Electric Vehicle, Csaba Toth-Nagy
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was the detailed examination of a Planetary Combination Hybrid Electric Vehicle design (PC-Hybrid). The PC-Hybrid unites all the advantages of the existing hybrid electric vehicle powertrain concepts, such as series, parallel and combination, while eliminating the disadvantages of each.;The PC-Hybrid powertrain is built up of an internal combustion engine, and two electric motor/alternators connected together via a planetary gear set. Several different powertrain configuration layouts were investigated as possible setups of the PC-Hybrid and the two most promising ones were chosen for further investigation and simulation. A control strategy has been developed for the optimal …
Evaluation Of Survival And Recovery Characteristics Of Bifidobacteria As Indicators Of Fecal Pollution Of Water, John Elmer Ravenscroft Jr.
Evaluation Of Survival And Recovery Characteristics Of Bifidobacteria As Indicators Of Fecal Pollution Of Water, John Elmer Ravenscroft Jr.
Graduate Theses, Dissertations, and Problem Reports (ETD)
The examination of aquatic environments for bacterial indicator organisms has proven to be a useful and well-established practice for the purpose of monitoring microbiological water quality. An ideal indicator of fecal pollution should be present in sufficient density to allow detection, present simultaneous with pathogen(s), incapable of aftergrowth in external aquatic environments, easy to enumerate, and exclusively of fecal origin. Unfortunately, none of the indicator organisms presently in use today meet all of these requirements. Bifidobacteria show promise as indicators of fecal pollution in water with the additional ability of potentially distinguishing between fecal pollution of human and animal origin. …
Optimization Of A Helicon Plasma Source For Maximum Density With Minimal Ion Heating, Matthew M. Balkey
Optimization Of A Helicon Plasma Source For Maximum Density With Minimal Ion Heating, Matthew M. Balkey
Graduate Theses, Dissertations, and Problem Reports (ETD)
Measurements of electron density and perpendicular ion temperatures in an argon helicon plasma are presented for five different antennas: A Nagoya type III antenna, a double-saddle antenna, a 19 cm long m = +1 helical antenna, a 30 cm long m = +1 helical antenna and a 19 cm m = +1 helical antenna with wide straps. Electromagnetic wave measurements in the range from 100 kHz to 50 MHz are also presented for a wide range of plasma parameters. The data show a clear transition between RF power coupling to the plasma to create density and coupling to heat ions. …
Longwall Weighting Events At Phalen Colliery, Nova Scotia, Canada, Robert J. Macdonald
Longwall Weighting Events At Phalen Colliery, Nova Scotia, Canada, Robert J. Macdonald
Graduate Theses, Dissertations, and Problem Reports (ETD)
Weightings are dynamic phenomenon observed in mines where coal is extracted using the longwall mining method. Weightings are characterized by high convergence rates within the powered supports which maintain roof stability along the longwall face. Rapid convergence is induced by ground pressures that exceed the load capacity of the supports, and forces them to yield. A weighting event need not necessarily impact the mining process negatively, but notable cases exist where weightings have caused extensive damage to roof strata resulting in large roof falls and prolonged periods of lost coal production.;This thesis describes the history of four longwall panels (No's …
Process Control Of Applied Laser System For Enhanced Glass Production, Liyun Zheng
Process Control Of Applied Laser System For Enhanced Glass Production, Liyun Zheng
Graduate Theses, Dissertations, and Problem Reports (ETD)
Existing glass crack-off methods often result in considerable loss of glassware and require subsequent edge finishing that is labor intensive. The main objective of this dissertation is to contribute to the development of a laser-enhanced cutting and finishing method that will decrease waste and improve productivity in the manufacturing of handblown glass.;The main objectives of this dissertation were to perform modeling and simulation of the laser glass interaction, to contribute to the lab prototype machine construction, to participate in experiments to investigate the process parameters governing successful glass cutting, and to pursue the design and validation of controls for the …
Formal Specification Of Requirements For Analytical Redundancy-Based Fault -Tolerant Flight Control Systems, Diego Del Gobbo
Formal Specification Of Requirements For Analytical Redundancy-Based Fault -Tolerant Flight Control Systems, Diego Del Gobbo
Graduate Theses, Dissertations, and Problem Reports (ETD)
Flight control systems are undergoing a rapid process of automation. The use of Fly-By-Wire digital flight control systems in commercial aviation (Airbus 320 and Boeing FBW-B777) is a clear sign of this trend. The increased automation goes in parallel with an increased complexity of flight control systems with obvious consequences on reliability and safety. Flight control systems must meet strict fault-tolerance requirements. The standard solution to achieving fault tolerance capability relies on multi-string architectures. On the other hand, multi-string architectures further increase the complexity of the system inducing a reduction of overall reliability.;In the past two decades a variety of …
Breastfeeding Personal Efficacy Beliefs Of Women University Students, Ann Pollard Cleveland
Breastfeeding Personal Efficacy Beliefs Of Women University Students, Ann Pollard Cleveland
Graduate Theses, Dissertations, and Problem Reports (ETD)
Many women do not initiate breastfeeding although breastfeeding promotes their baby's health. Three reasons why women do not breastfeed are women's mental organization, cultural beliefs about breastfeeding, and women's breastfeeding personal efficacy beliefs. The conceptual framework for personal efficacy beliefs is Bandura's social-cognitive theory (1992, 1995, 1997). This dissertation used a new research instrument to examine women university students' breastfeeding personal efficacy beliefs. The instrument was tested by mail survey techniques that resulted in a 70.6% respondent rate. University women's personal efficacy beliefs about breastfeeding factored into five factor subscales. In order of magnitude, the personal efficacy belief factors were …
Restimulation Candidate Selection Using Virtual Intelligence, Khalid Y. Mohamad
Restimulation Candidate Selection Using Virtual Intelligence, Khalid Y. Mohamad
Graduate Theses, Dissertations, and Problem Reports (ETD)
Due to the importance of well deliverability maintenance, a committee of specialists from Dominion East Ohio and other service companies meets every year to select the wells to be included in the deliverability maintenance plan. The application tool not only help in selecting the wells for deliverability maintenance plan but goes beyond that by designing the most optimum frac recipe.;The purpose of this study is to develop an engineering tool that will help petroleum engineers making a better decision for selecting well candidate and design well restimulation. The project focuses on a gas storage field and use data such as …
Improving The Simulation Of A Waterflooding Recovery Process Using Artificial Neural Networks, Edison Gil
Improving The Simulation Of A Waterflooding Recovery Process Using Artificial Neural Networks, Edison Gil
Graduate Theses, Dissertations, and Problem Reports (ETD)
The waterflood performance of the dual five-spot pilot project in the Stringtown oil field, situated in West Virginia, has been studied. A numerical simulator, called BOAST98, was used for the simulation purposes, after developing a reservoir description.;The producing horizon in the field is the Upper Devonian Gordon sandstone, which is characterized by severe heterogeneity due to the depositional environment. Using available core and log data and geological analysis, a reservoir characterization study was done. A preliminary reservoir description based on log porosity-core permeability correlation was improved by developing Artificial Neural Networks (A.N.N.), which incorporates geophysical well log information. These A.N.N.'s …
Improving Commercial Vehicle Crash Data Quality In West Virginia, Kris Sean Gillespie
Improving Commercial Vehicle Crash Data Quality In West Virginia, Kris Sean Gillespie
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was to identify methods to improve commercial carrier crash data in West Virginia including coal trucks. All organizations and agencies involved with commercial carrier safety need ready access to basic data describing the crash-involved operator, vehicle, and environment. Such data are necessary to any programmatic or engineering countermeasures. The basic approach used to accomplish the research objectives involved a series of regional meetings where law enforcement personnel expressed their opinions about ways to improve commercial vehicle crash data quality. These results were then weighted and prioritized. The top five solutions generated at these meetings were: …
Predicting A Detailed Permeability Profile From Minipermeameter Measurements And Well Log Data, Shawn D. Nines
Predicting A Detailed Permeability Profile From Minipermeameter Measurements And Well Log Data, Shawn D. Nines
Graduate Theses, Dissertations, and Problem Reports (ETD)
Permeability, along with the porosity, comprises one of the two most important properties in petroleum engineering with respect producing hydrocarbon fluids.;It is standard practice in the petroleum industry to determine permeability in one of two ways. These are pressure transient testing and core analysis. Both methods are expensive in their own ways. This research focuses on a way to minimize or limit the need for both of these testing procedures.;The purpose of this research was to utilize well log data, mainly gamma ray and density, Minipermeameter values, and basic information such as depth and spatial coordinates to predict permeability in …
Development Of An Integrated Project-Level Pavement Management Model Using Risk Analysis, Jennifer A. Reigle
Development Of An Integrated Project-Level Pavement Management Model Using Risk Analysis, Jennifer A. Reigle
Graduate Theses, Dissertations, and Problem Reports (ETD)
Historically, federal highway funding focused on the construction of new pavements and the upgrading of existing pavements. Today, much of the infrastructure is in place. Therefore, the focus of federal funding is shifting toward pavement maintenance and preservation. With this is mind, highway agencies are directing attention toward pavement preservation strategies that yield the greatest value from existing pavements.;Life cycle cost analysis (LCCA) is a decision-making tool that highway agencies may use in selecting an optimal pavement preservation strategy. Traditionally, LCCA models for pavement management use discrete input values that represent a conservative "best guess" of each parameter. Thus, inherent …
Finite Element Modeling Of Dowel -Jointed Plain Concrete Pavement Response To Thermal And Moving Traffic Loads, Michel Ramsis Fahmy
Finite Element Modeling Of Dowel -Jointed Plain Concrete Pavement Response To Thermal And Moving Traffic Loads, Michel Ramsis Fahmy
Graduate Theses, Dissertations, and Problem Reports (ETD)
The objective of this study was to develop Three Dimensional Finite Element Models (3D-FEM) that can be used to investigate the separate or combined effect of moving axle loads and thermal gradient on the response of dowel Jointed Portland Cement Concrete Pavement (JPCCP) structures. The availability of a mechanistic tool that can be used for an accurate prediction of rigid pavement response to such loads would enable designing longer lasting pavements and understanding some of its modes of distress. In this respect, finite element modeling offers a powerful tool for the simulation of the structural behavior of pavements under the …
Development Of A Membrane Resistance Based Modeling Framework For Comparison Of Ultrafiltration Processes, David Albert Masciola
Development Of A Membrane Resistance Based Modeling Framework For Comparison Of Ultrafiltration Processes, David Albert Masciola
Graduate Theses, Dissertations, and Problem Reports (ETD)
A parametric study was conducted to develop a more general modeling framework as a basis for comparison of ultrafiltration membrane modules and separation processes. Discrete experiments were performed to examine the effects of operating parameters on permeate flux behavior in the tubular and high-shear rotary ultrafiltration (HSRUF) systems using a synthetic metal working (MW) fluid as a surrogate feed stream due to its relevance in industrial process and treatment applications. The conventional thin-film model was successfully applied to permeate flux data collected at low feed oil concentrations; however, model predictions at high concentrations were physically meaningless due to the formation …
Design, Construction, And Evaluation Of Coal Extraction Pilot Plant To Manufacture Coal-Based Carbon Pitch, Brian Wayne Bland
Design, Construction, And Evaluation Of Coal Extraction Pilot Plant To Manufacture Coal-Based Carbon Pitch, Brian Wayne Bland
Graduate Theses, Dissertations, and Problem Reports (ETD)
A solvent extraction technique for removing mineral matter, including the inorganic sulfur, from coal has been developed by the Department of Chemical Engineering at WVU. The extraction is preformed at mild conditions (202°C and atmospheric pressure) using the solvent N-Methyl-2-Pyrrolidone (NMP). Laboratory results have shown that this technique yields a clean coal product containing less than 1 percent ash and virtually no inorganic sulfur.;This research was conducted for further process design and economic development of an industrial-scale extraction process.;This research reported the possibility of production scale processing by constructing a pilot plant. The pilot plant was used to explore the …
Evaluation Of Opacity, Particulate Matter, And Carbon Monoxide From Heavy-Duty Diesel Transient Chassis Tests, Ronald Page Jarrett
Evaluation Of Opacity, Particulate Matter, And Carbon Monoxide From Heavy-Duty Diesel Transient Chassis Tests, Ronald Page Jarrett
Graduate Theses, Dissertations, and Problem Reports (ETD)
Opacity and emission data were collected from heavy-duty diesel engines exercised through snap-acceleration tests and transient chassis dynamometer tests. Emission data were gathered using the West Virginia University (WVU) Transportable Heavy Duty Vehicle Emission Testing Laboratories (THDVETL) and opacity data were collected from two opacity meters; the Wager 650CP full flow opacity meter and the Bosch RT 100 partial flow opacimeter. Results showed that the Bosch peak opacity readings were consistently higher than the Wager peak opacity readings, and both meters showed little correlation with filter-captured particulate matter (PM). It was also observed that the snap-acceleration test did not identify …
Parallelization Of Ecg Template-Based Abnormality Detection, Sherry Lea Kratsas
Parallelization Of Ecg Template-Based Abnormality Detection, Sherry Lea Kratsas
Graduate Theses, Dissertations, and Problem Reports (ETD)
In order to develop techniques to predict cardiac arrest, long-term study of electrocardiogram (ECG) data needs to be done to detect changes in electrical activity of diseased hearts. In the past, limitations of computing power and storage space restricted the duration of long-term studies to several days. However, with today's technological advancement, data collection can be extended to months or years. The goal of this thesis research is to evaluate several alternatives for distributing the analysis of ECG data over multiple processors. Parallel algorithms utilizing Correlation Waveform Analysis (CWA) were implemented to compare individual heartbeats and form heartbeat templates. The …
Treatment Of Acid Mine Drainage With Weirton Steel Slags, Prashant Seshadri
Treatment Of Acid Mine Drainage With Weirton Steel Slags, Prashant Seshadri
Graduate Theses, Dissertations, and Problem Reports (ETD)
Bed experiments were conducted to treat acid mine drainage with Weirton steel slag which contained 72.22% as Ca(OH)2 equivalent. The Acid Mine Drainage (AMD) sample was obtained from the T&T site located in northern West Virginia. The pH of the solution was 2.56 and the iron content was 89 ppm. The bed was constructed with tin-coated aluminum sheets and was 11&feet;8-1/4&inches; long, 2&inches; wide and 2&inches; high. The experiments were conducted by charging the bed half full with the slag particles (4 x 40 mesh) and then pumping AMD solution (T&T) through the bed. The flow rates used were 78 …
Students' Perception Of Performance Through Self-Assessment, Javier Dejesus Coronado-Aliegro
Students' Perception Of Performance Through Self-Assessment, Javier Dejesus Coronado-Aliegro
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study was designed as a qualitative investigation and it focuses on the non-graded self-assessment adult ESL students make of their performance. It is based upon findings from previous studies of self-assessment in several settings (Glazer, 1999; Glazer et al., 1995; Optiz, 1995; Manning, 1997; Levy, 1999; Fazey, 1993; Boud, 1992; Orsmond et al., 1997; Sullivan and Hall, 1997; and Lan, 1996). The present research reports and analyzes data collected from eleven students who expressed their views concerning their performance through a checklist, two questionnaires and an interview in an ESL setting. The data collected and analyzed suggest that students …
Development And Application Electrochemical And Spectrophotometric Methods Based Upon Ac Potential Modulation For Characterization Of Hybrid Bilayer Membranes And Electroactive Self -Assembled Monolayers Supported On Gold Electrodes, Dmitri A. Brevnov
Graduate Theses, Dissertations, and Problem Reports (ETD)
Applications of the electrochemical method, AC Voltammetry (ACV), and its modifications based upon monitoring ac current as a function of ac potential modulation are described. The first chapter involves investigating the effect of a short peptide, melittin, on both hybrid bilayer membrane (HBM) dielectric properties and HBM resistance to heterogeneous electron transfer. These effects are discussed in terms of three possible mechanisms by which melittin may affect HBMs. In the second chapter, a modification of ACV, second harmonic ACV, is considered. A data processing method is suggested to analyze data collected at high perturbation frequencies at which the effect of …
Characterization And Applications Of Pulsed Millisecond Glow Discharge Sources, Cris Lee Lewis
Characterization And Applications Of Pulsed Millisecond Glow Discharge Sources, Cris Lee Lewis
Graduate Theses, Dissertations, and Problem Reports (ETD)
Most modern analytical techniques are derived from coupled methods involving a chromatographic separation followed by mass spectrometric detection. These techniques are employed in modern laboratories in the form of gas and liquid chromatography mass spectrometric systems. Chromatography methods separate and concentrate different chemical species based on phase partitioning. Once separated, the sample is analyzed mass spectrometrically, where further information and identification of the analyte may be deduced based on its inherent mass-to-charge ratio. However, following chemical separation and previous to any mass spectrometric detection, the analyte most be ionized. To date there are numerous possible methods for ionization, however, they …
Evaluation Of The Use Of Remotely Sensed Images To Speciate Mixed Appalachian Forests, Doru Ioan Pacurari
Evaluation Of The Use Of Remotely Sensed Images To Speciate Mixed Appalachian Forests, Doru Ioan Pacurari
Graduate Theses, Dissertations, and Problem Reports (ETD)
Advancements in technology have led to development of various new sensors and platforms. Among them, the airborne digital camera has potential for use in detailed forest vegetation management, and they offer a number of advantages over conventional aerial photographs. The aim of the study was to determine the ability to speciate mixed Appalachian hardwood forests using the Airborne Data Acquisition and Registration (ADAR) System 1000, and to determine the optimal spatial resolution and the optimal scale of the acquired images. Digital images of a 200-ha area in west central West Virginia were acquired for the study.;The first objective of the …
Relationship Between Cutting Parameters And Bit Geometry In Rotary Cutting, Srikanth Addala
Relationship Between Cutting Parameters And Bit Geometry In Rotary Cutting, Srikanth Addala
Graduate Theses, Dissertations, and Problem Reports (ETD)
The main objective of this research was to investigate the relationship between cutting parameters (cutting force, penetration force, specific energy, specific respirable dust) and the bit geometry parameters (angle of the bit tip, bit tip size and shape of the bit) in order to reduce the amount of specific respirable dust generated and the specific energy consumed in rotary cutting. In the cutting process when two grooves are made in the rock at certain spacing, a land/ridge is formed between the two adjacent grooves. If that land/ridge can be removed in a cutting cycle, then a clean surface will be …
Detection Of Subsurface Anomalies In Composite Bridge Decks Using Infrared Thermography, Hasan Moh'd Alqennah
Detection Of Subsurface Anomalies In Composite Bridge Decks Using Infrared Thermography, Hasan Moh'd Alqennah
Graduate Theses, Dissertations, and Problem Reports (ETD)
This document presents the findings of an experimental study on the use of Infrared Thermography for nondestructive evaluation of subsurface anomalies in composite bridge decks.;Composite bridge deck specimens were constructed in the laboratory with varying subsurface delamination conditions such as sizes, thicknesses and filler materials. These simulated delaminations were placed between the 3/8&inches; thick wearing surface and the top of the fiber reinforced polymer (FRP) deck. The laboratory specimens were tested using the infrared imaging system. The infrared images from the delaminated specimens were compared with solid (undamaged) specimens to study the effect of subsurface anomalies (delaminations) on the infrared …
Effects Of Plant Flavonoids On The Fate Of Polynuclear Aromatic Hydrocarbons In Rhizosphere Soil, Xiujin Qui
Effects Of Plant Flavonoids On The Fate Of Polynuclear Aromatic Hydrocarbons In Rhizosphere Soil, Xiujin Qui
Graduate Theses, Dissertations, and Problem Reports (ETD)
High-molecular-weight polynuclear aromatic hydrocarbons (PAHs) are persistent in the environment although a wide variety of microorganisms can metabolize PAHs. In the past decades, laboratory and filed studies have shown that PAH degradation in soil is often limited by poor bioavailability and oxygen availability. Bound residue formation of PAHs with macromolecules of soil organic matter is an important fate mechanism. More recently, phytoremediation for PAH-contaminated soils is being explored. It is believed that PAH degradation may be enhanced in rhizosphere soil due to the improved aeration condition and the active soil microbial community sustained by root exudates. Whether certain root exudates …
Assessment Of A Space Shuttle Trajectory Evaluation System (Dolilu Ii), Diwakar Chakravarthy
Assessment Of A Space Shuttle Trajectory Evaluation System (Dolilu Ii), Diwakar Chakravarthy
Graduate Theses, Dissertations, and Problem Reports (ETD)
DOLILU II is a ground control system that generates space shuttle's launch trajectories, first stage guidance commands and verifies whether the generated trajectories are safe for the flight. It is a safety critical system and a high degree of confidence in its safety and reliability must be gained through assessment. We addressed three issues related to its safety and reliability assessment. We developed a reliability assessment framework for DOLILU II system. We proposed techniques to speed up test case execution and designed methodologies for the generation of input conditions needed to test the system.;We used a Bayesian statistical framework for …
Determining Organic Vapor Cartridge Breakthrough Characteristics Of Jp-8 During Aircraft Fuel Tank Entry Operations, Kevin W. Culp
Determining Organic Vapor Cartridge Breakthrough Characteristics Of Jp-8 During Aircraft Fuel Tank Entry Operations, Kevin W. Culp
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study assessed the service life of organic vapor cartridges exposed to jet Propulsion Type 8 fuel vapor. Two experiments were conducted that involved exposing 45 cartridges to three challenge concentrations (300, 600, and 1200 parts per million) of fuel vapor and two relative humidity levels (50 and 80 percent). The impact on service life of (1) high relative humidity conditions and (2) prior static exposure to fuel vapor were evaluated.;This study concluded that the 80 percent relative humidity test condition had a statistically significant effect on breakthrough time versus the 50 percent relative humidity condition, reducing service life by …