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Velocity Profile In Confined Elliptic Fractures, Stephen Ronald Pack Jr. Dec 1998

Velocity Profile In Confined Elliptic Fractures, Stephen Ronald Pack Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

The primary objective of this research is to determine the friction inside a smooth fracture and to incorporate the effect of friction on a fluid transient inside a tapered-elliptical-confined fracture. In order to do so, the non-uniform velocity profile in an elliptic fracture with laminar flow of both Newtonian and non-Newtonian fluids was calculated. A transient flow computer program is presented using the method of characteristics, to show the frictional effects on acoustic damping. However for flow inside a hydraulic fracture, the 3D velocity profile is highly non-uniform, and the use of Vav creates an error as Vmax >> Vav. The …

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Prediction Of Turbulent Mixing At The Interface Of Density Stratified, Shear Flows Using Cfd, Matthew Robert Umbel Dec 1998

Prediction Of Turbulent Mixing At The Interface Of Density Stratified, Shear Flows Using Cfd, Matthew Robert Umbel

Graduate Theses, Dissertations, and Problem Reports (ETD)

Numerical simulations were performed involving stratified, shear flows that have been investigated experimentally. One set of simulations dealt with a homogeneous shear flow involving miscible fluids. The other set of simulations dealt with a developing shear layer involving immiscible fluids. The re-fueling of a compensated fuel/ballast tank, which is partially characterized by a shear layer, was also simulated. In all the simulations a single fluid, scalar transport multiphase model and the k-epsilon turbulence model were used. In the simulations involving miscible fluids an interfacial thickness relationship given by delta/H∼(Ri*)--2.1 and an entrainment relationship given by E∼(Ri*)--1.1 were predicted. These relationships …

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Pseudospectral Techniques For Non -Smooth Evolutionary Problems, Chris Palmer Guenther Dec 1998

Pseudospectral Techniques For Non -Smooth Evolutionary Problems, Chris Palmer Guenther

Graduate Theses, Dissertations, and Problem Reports (ETD)

A pseudospectral approach is used to solve non-smooth evolutionary problems using Fourier collocation and Chebyshev collocation. It is well known that pseudospectral methods for smooth problems can offer superior accuracy over finite difference and finite element methods.;This paper explores the use of pseudospectral methods for non-smooth evolutionary problems in the area of hyperbolic heat transfer. Boundary and initial conditions are considered which cause instantaneous jumps, in the temperature and flux, prior to the propagation of a thermal wave into the medium. There is a considerable amount of literature that has investigated hyperbolic heat transfer under similar conditions, the common problems …

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Design Analysis Of Single-Span Advanced Composite Deck-And-Stringer Bridge Systems, Brian James Brown Dec 1998

Design Analysis Of Single-Span Advanced Composite Deck-And-Stringer Bridge Systems, Brian James Brown

Graduate Theses, Dissertations, and Problem Reports (ETD)

The advantages of advanced composite materials (ACM) over conventional materials motivate their use in highway bridges for rehabilitation and replacement of structures. However, the complexity of the composites has created a need for simplified design analysis procedures that account for both the geometry and material properties of ACM members and systems.;An analytical/experimental study of fiber-reinforced plastic (FRP) composite bridges consisting of cellular box decks and wide-flange I-beams as stringers is presented. The design analysis covers: (1) ply stiffnesses and strengths; (2) laminate engineering stiffnesses; (3) apparent stiffness properties for composite decks; and (4) stringer stiffness properties. Finite element modeling is …

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Fault-Injection Through Model Checking Via Naive Assumptions About State Machine Synchrony Semantics, Sabina Joseph Dec 1998

Fault-Injection Through Model Checking Via Naive Assumptions About State Machine Synchrony Semantics, Sabina Joseph

Graduate Theses, Dissertations, and Problem Reports (ETD)

Software behavior can be defined as the action or reaction of software to external and/or internal conditions. Software behavior is an important characteristic in determining software quality. Fault-injection is a method to assess software quality through its' behavior. Our research involves a fault-injection process combined with model checking. We introduce a concept of "naive assumptions" which exploits the assumptions of execution order, synchrony and fairness. "Naive assumptions" are applied to inject faults into our models. We use linear temporal logic to examine the model for anomalous behaviors. This method shows us the benefits of using fault-injection and model checking and …

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Determination And Analysis Of Natural Gas Vehicle Tailpipe Emissions Based On Continuous Cvs Measurement, Jingang Fu Dec 1998

Determination And Analysis Of Natural Gas Vehicle Tailpipe Emissions Based On Continuous Cvs Measurement, Jingang Fu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Code of Federal Regulations Title 40 (CFR-40) specified a formula for calculating constant Dilution Factor (DF) to account for background pollutants in Constant Volume Sampler (CVS) emissions measurement system. However, it is recognized that the DF is dynamically changing due to the CVS mechanism. Based on the continuous measurement data obtained from natural gas vehicle emissions testing, a new approach was used in this study to calculate instantaneous DF of the CVS system during the test cycle. Using the instantaneous DF improves the accuracy of mass emission measurements, especially when the exhaust pollutant concentrations were approaching that in the ambient …

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Perturbation Studies Of Excitable Media, Lisa Elizabeth Seagraves Dec 1998

Perturbation Studies Of Excitable Media, Lisa Elizabeth Seagraves

Graduate Theses, Dissertations, and Problem Reports (ETD)

Poly(N-isopropylacrylamide) (PNIPA) based systems are probably the most often studied polymer gels due to their dramatic change in volume, swelling and deswelling. Since this system has the best response to pH between 4 and 7, the ferrocyanide-iodate-sulfite (FIS) reaction, which exhibits pH oscillations between 4 and 7.5 in a continuously stirred tank reactor (CSTR), is a good candidate for studies of oscillatory gel systems.;This work also focused on two dynamical phenomena in the ruthenium catalyzed Belousov-Zhabotinsky (BZ) reaction. One is self-organized criticality and the other is periodic forcing and how they can be studied with the BZ reaction. Self-organized criticality …

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Fluency And Controlled-Operant Training Methods, Finnur Oddsson Dec 1998

Fluency And Controlled-Operant Training Methods, Finnur Oddsson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The study compared the effectiveness three computerized training methods with respect to behavioral outcomes correlated with fluency. Subjects were trained to translate binary numbers into decimal numbers. Responses were made orally with the use of voice recognition software. One training method presented 50 stimuli on a computer monitor at a time (No ITIs). The other two methods (0s and 1.5s ITIs) presented stimuli separately on the monitor using discrete trials. Inter trial intervals were manipulated for the latter training methods. Results showed that all subjects achieved fluent performance on the training task. Subjects reached rate criterion faster and with less …

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Implementing Constructivism In The Middle School Classroom, Christina Paparozzi Dec 1998

Implementing Constructivism In The Middle School Classroom, Christina Paparozzi

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study defines the components of a middle school history curriculum based on a theory of learning consistent with the use of cognitive tools and the tenets of constructivism. Utilizing a comparative analysis of learning theories encompassing developmental and constructivist beliefs and their influence on appropriate instructional design, the research addresses the necessary pairing of instructional planning and learning theory. Additionally, an examination of linguistic tools and their relationship to cultural development and distinctive kinds of comprehension, as well as specifics of the various learning stages, preferences, and skills are used to provide a rationale. This analysis is employed in …

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Outline And Nearly Outline Triple Systems Of Even Index, Michael Neill Ferencak Dec 1998

Outline And Nearly Outline Triple Systems Of Even Index, Michael Neill Ferencak

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main result of this work describes a completely novel structural result for (v, 3, lambda)-designs in the case when lambda is even. Such designs are known as triple systems. Given a finite collection of n elements, a triple system of order n and index lambda is a collection of subsets of size three chosen from the given set with the property that each distinct pair of elements from the set occurs in exactly lambda of the triples. It is well known for what values of n and lambda such systems exist. A partial triple system of order n and …

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Generalized Edge Connectivity In Graphs, Kamal P. Hennayake Dec 1998

Generalized Edge Connectivity In Graphs, Kamal P. Hennayake

Graduate Theses, Dissertations, and Problem Reports (ETD)

The edge-connectivity l of a connected graph is the minimum number of edges whose deletion produces a graph with two components. For an integer l > 1, the l-edge connectivity of a graph with | V| ≥ l, denoted by l l, is the smallest number of edges whose removal results in a graph with l components. The strength of G, denoted by l&d1; (G), is the maximum value of l (H), where H runs over all subgraphs of G. In this dissertation we study lower bounds of l l and optimal graphs that reach the lower bound. Former results in …

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Local Damage Analysis Of Fiber -Reinforced Polymer Matrix Composites, Arsenio Domingo Caceres Dec 1998

Local Damage Analysis Of Fiber -Reinforced Polymer Matrix Composites, Arsenio Domingo Caceres

Graduate Theses, Dissertations, and Problem Reports (ETD)

While it is widely recognized that failure occurs as a result of damage accumulation, characterization of composite material behavior is currently limited to obtaining the elastic properties and the strength values. With such information, it is not possible to assess the remaining life of a structural component or to estimate the likelihood of failure as a function of the time in service. The present investigation concerns the development of a continuum damage mechanics (CDM) formulation for polymer-matrix composites assuming the damage accumulates in the matrix, fiber, and fiber-matrix interphase regions. A local approach was taken by dividing the analysis of …

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Multi-Selectible Continua, Joseph Edward Mcparland Aug 1998

Multi-Selectible Continua, Joseph Edward Mcparland

Graduate Theses, Dissertations, and Problem Reports (ETD)

A particular coexistence of multiple continuous selections (a "multi-selection") within a function space for a non-degenerate metric continuum X is investigated for the hyperspaces 2X and C(X). It is demonstrated that (i) multi-selections do not exist for 2X and that (ii) the existence of a multi-selection for C(X) is equivalent to X being a dendrite.

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Language Imperialism Versus Linguistic Rights: The Case Of Native Americans., Jonathan Woodruff Maffay Jan 1998

Language Imperialism Versus Linguistic Rights: The Case Of Native Americans., Jonathan Woodruff Maffay

Graduate Theses, Dissertations, and Problem Reports (ETD)

From the days of the Old Testament and Tower of Babel through the nineteenth century efforts to create artificial languages, the human race has longed for a universal language. Its purpose would be to bind the linguistically diverse people of the world into a cohesive whole. With English apparently well on its way to becoming just such a universal language, many people are now growing concerned at the prospect. For them English is an imperial language that threatens the world’s rich cultural and language complexity. Linguistic rights activists have now begun trying to counter this universalizing trend with language repair …

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Pausing And Escape On Fixed-Interval Schedules: Effects Of Stimuli Correlated With Different Reinforcer Magnitudes And Different Reinforcement Rates., Leo A. Carlin Jan 1998

Pausing And Escape On Fixed-Interval Schedules: Effects Of Stimuli Correlated With Different Reinforcer Magnitudes And Different Reinforcement Rates., Leo A. Carlin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Research has shown that both pausing and escape are controlled jointly by past and upcoming conditions of reinforcement. The present research was designed to investigate the contextual variables that influence pausing and escape on FI schedules and to assess further the functional similarities between pausing and escape. It was of particular interest that the effects of past events have been observed long after they had been removed from the environment of the organism. To shed light on the nature of control by such past events on pausing and escape, three experiments were arranged with fixed-interval schedules that manipulated stimuli correlated …

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An Economic Analysis Of State Lotteries In America., Thomas Andrew Garrett Jan 1998

An Economic Analysis Of State Lotteries In America., Thomas Andrew Garrett

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is an economic analysis of state lotteries in America. The previous areas of lottery research and the dissertation research agenda are discussed in the first chapter. The second chapter provides statistics on state lotteries. State lottery sales, net lottery revenues, the growth of lottery sales in the United States, and target sources of net lottery revenues are all presented in Chapter 2. The third chapter of the dissertation examines the process of state lottery adoption, focusing on the behavior of state legislators and voters. Insight into the significant determinants of lottery adoption are presented, along with support for …

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A Two-Perspective Study On The Modern Chinese Economy: Foreign Direct Investment And Regional Development., Chuanliu Ni Jan 1998

A Two-Perspective Study On The Modern Chinese Economy: Foreign Direct Investment And Regional Development., Chuanliu Ni

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many research efforts have been devoted to the role of foreign direct investment (FDI) on China's economic achievement, to the general FDI distribution pattern as well as to regional economic disparities in China. The objectives of this dissertation are to address several issues in recent research, develop a model for FDI influx into China, examine major factors influencing FDI distribution in China and a separate study on China's regional economic disparities. Beginning with a literature survey on FDI study, I theoretically examine the (FDI) self-reinforcing model. I justify some of the assumptions of the FDI self-reinforcing model. I developed a …

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A Design Of Fault Tolerant Flight Control Systems For Sensor And Actuator Failures Using On-Line Learning Neural Networks., Younghwan An Jan 1998

A Design Of Fault Tolerant Flight Control Systems For Sensor And Actuator Failures Using On-Line Learning Neural Networks., Younghwan An

Graduate Theses, Dissertations, and Problem Reports (ETD)

The research in this document focuses on the performance of a neural network-based fault tolerant system within a flight control system. This fault tolerant flight control system integrates sensor and actuator failure detection, identification, and accommodation (SFDIA and AFDIA). The SFDIA task is achieved by incorporating a main neural network (MNN) and a set of n decentralized neural networks (DNNs) for a system with n sensors assumed to be without physical redundancy. Particularly, the purpose of the MNN is to detect a wide variety of sensor failures while the purpose of the DNNs is to identify the particular sensor that …

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Identification Of Content, Priority, And Methods Of Instructional Delivery For A Women's Health Component In An Internal Medicine Residency Program: A Modified Delphi Study., Alicia Jean Williams Jan 1998

Identification Of Content, Priority, And Methods Of Instructional Delivery For A Women's Health Component In An Internal Medicine Residency Program: A Modified Delphi Study., Alicia Jean Williams

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this research was to determine the general content, topics and sub-topics, priorities of the content, and methods of instructional delivery for a women's health component within the Internal Medicine residency program at West Virginia University. Panel members chosen for the study were MD's and PhD's who worked in a health-related field for at least two years and had an interest in women's health. A modified Delphi method was used for this study to determine the content. Panel members also identified their current and preferred methods of instructional delivery in a separate section of the study. The panel …

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A Universal Amperometric Membrane-Covered Gas-Sensing Electrodes System: Measurement Of Dissolved Oxygen, Ozone And Chlorine Dioxide., Rener Wang Jan 1998

A Universal Amperometric Membrane-Covered Gas-Sensing Electrodes System: Measurement Of Dissolved Oxygen, Ozone And Chlorine Dioxide., Rener Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

A Universal Amperometric Membrane-Covered Gas-Sensing Electrode System has been designed which can be used with a wide variety of electrochemical sensors. The system is composed of two parts: an electrode detection unit consists of an Intel 8051 microprocessor as the control unit which receives operational commands through the serial port of a personal computer. The assembly language has been written and is embedded in a 32K EPROM and the data collected are temporarily stored in a 32K RAM. A potentiostat with an auto-adjustable 100 nA to 100 {dollar}\\mu{dollar}A range is used to polarize the electrode. A 12 bit D/A convertor …

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A Toolbox Of Intelligent Solutions For Hydraulic Fracturing Models., Andrei Sergiu Popa Jan 1998

A Toolbox Of Intelligent Solutions For Hydraulic Fracturing Models., Andrei Sergiu Popa

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study is to develop a Front-End and an Optimization Routine that will help petroleum engineers to design optimum treatment schedules for hydraulic fracturing. This tool reduces the time engineers spend designing optimum treatment schedules by proposing a solution based on virtual intelligence. Neural networks and genetic algorithms are integrated in a software application to achieve the objective of this study. A methodology to reduce the total number of layers to four characteristic layers was developed. Using this methodology, two types of neural networks were trained. A new selection method was developed for the genetic algorithm process. …

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A Transient Computational Fluid Dynamic Model Of A Unit Injector Using Methanol Fuel., Eugene Anthony Mckenzie Jan 1998

A Transient Computational Fluid Dynamic Model Of A Unit Injector Using Methanol Fuel., Eugene Anthony Mckenzie

Graduate Theses, Dissertations, and Problem Reports (ETD)

The use of alternative fuels such as Ethanol, Methanol and Natural Gas in automotive applications has increased due to the strict environmental regulations. These are used to reduce automotive emissions, especially in heavy trucks and city bus fleets. Most of these vehicles use diesel fuel as their primary fuel. Trucks and buses with Detroit Diesel engines have the option to operate using methanol as their primary fuel instead of diesel fuel. Due to the low lubricity of methanol fuel, the unit fuel injectors injecting methanol fuel have a shorter operating life than those injecting diesel fuel do. To study the …

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The Ambassador Of Development: Aretas Brooks Fleming, West Virginia's Political Entrepreneur, 1839-1923., Jeffery Blane Cook Jan 1998

The Ambassador Of Development: Aretas Brooks Fleming, West Virginia's Political Entrepreneur, 1839-1923., Jeffery Blane Cook

Graduate Theses, Dissertations, and Problem Reports (ETD)

Aretas Brooks Fleming (1839–1923) businessman and Democratic party boss came from a prominent Fairmont family with extensive political connections throughout the region. He was not rich, but was well born, and able and followed the Virginia tradition of marrying well. He used an extensive kinship network, which was a community unto itself, to build a successful law practice and to start his climb up the political ladder. Fleming's dedication brought both political and business success, as he served in the West Virginia legislature and then judge of the second judicial circuit of West Virginia. Fleming's basic interest in politics, however, …

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An Assessment Of Presidential Perceptions Of Goal Compliance Stated In West Virginia Senate Bill 547., Mark Stephen Carter Jan 1998

An Assessment Of Presidential Perceptions Of Goal Compliance Stated In West Virginia Senate Bill 547., Mark Stephen Carter

Graduate Theses, Dissertations, and Problem Reports (ETD)

The article is a report of a qualitative study to determine whether Presidents of West Virginia higher education institutions maintain attitudes commensurate with goal statements contained in Senate Bill 547: a West Virginia legislative initiative that requires institutional compliance with various legislated goals. Findings of the study are presented in a brief, case study format for each President. In addition, a global assessment of Presidential perceptions with associated issues of compliance/noncompliance is presented.

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The Relationship Between Student Characteristics And Math Achievement When Using Computer Spreadsheets., Jeanne Heindel Gasiorowski Jan 1998

The Relationship Between Student Characteristics And Math Achievement When Using Computer Spreadsheets., Jeanne Heindel Gasiorowski

Graduate Theses, Dissertations, and Problem Reports (ETD)

The use of computer hardware and software technology in schools is on the rise while there are increasing demands for success in mathematics by all students, despite diverse backgrounds. The problem is to determine the characteristics of students who most benefit from the use of spreadsheet software as a cognitive tool to assist them as they learn to organize and analyze data. For a period of six weeks, 114 seventh grade students received standard instruction in their mathematics classes in basic statistics/data analysis content. Concurrently, in a separate computer class, the students received instruction which focused on the use of …

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Parametric Study Of Dust Generation With Rock Ridge Breakage Analysis Using A Simulated Continuous Miner., Venkata Babu Achanti Jan 1998

Parametric Study Of Dust Generation With Rock Ridge Breakage Analysis Using A Simulated Continuous Miner., Venkata Babu Achanti

Graduate Theses, Dissertations, and Problem Reports (ETD)

Efficient rock breakage is a result of optimum use of available resources in a continuous mining system. Research demonstrates that specific respirable dust must be kept at a minimum in order to produce the optimum parameters of rock breakage process. A cutting process that induces large chips of cut product results in minimum respirable dust. To produce larger chips of cut product, a correct inter-play of several bit geometry related parameters is essential. As the ridges/lands between two adjacent grooves are removed, a free surface is available for subsequent cuts. The nature of ridge failure is a function of the …

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Time Series Forecasting Of Mexican Trade Prices., Horacio Cardiel Perez Jan 1998

Time Series Forecasting Of Mexican Trade Prices., Horacio Cardiel Perez

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main purpose of this study is to address the question of how price forecasts can be produced in an accurate, reliable, and cost-effective form for planning and policy purposes in Mexican agriculture. The need for this stems from the recent opening of the Mexican economy, which resulted in a decrease government intervention, such that market demand, supply and prices are now influenced more by international events. Thus, this work investigates the application of univariate time series models to forecasting the trade prices for corn, dry beans, and sorghum in an import side, and tomatoes, broccoli, coffee, and sugar as …

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Synthesis And Evaluation Of Novel Polymeric Stationary Phases For Capillary Liquid Chromatography And Electrochromatography., Zhixin Jessica Tan Jan 1998

Synthesis And Evaluation Of Novel Polymeric Stationary Phases For Capillary Liquid Chromatography And Electrochromatography., Zhixin Jessica Tan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The stationary phase is at the heart of chromatographic separation techniques. In the pursuit of higher separation efficiency and resolving power, methods for the synthesis of novel polymeric stationary phases were developed. These stationary phases were evaluated using microscale separation techniques that have inherent high efficiency: open-tubular liquid chromatography (OT-LC), open-tubular capillary electrochromatography (OT-CEC), and packed column capillary electrochromatography (PC-CEC). A new technique was developed for the in situ synthesis of thin film polymer stationary phases inside small diameter fused silica capillaries. This technique allows the use of readily available and inexpensive polyimide jacketed capillaries, and provides greater control over …

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Economies Of Scale, Overcapitalization And Asset Pricing In The United States Electric Utility Industry., Russell Rhine Jan 1998

Economies Of Scale, Overcapitalization And Asset Pricing In The United States Electric Utility Industry., Russell Rhine

Graduate Theses, Dissertations, and Problem Reports (ETD)

The following dissertation is the consolidation of three research projects in the U.S. electric utility industry. The first essay tests for scale economies in the electric utility industry using a panel data set of fossil fuel and nuclear fuel utilities. In addition, a variable cost function is used as opposed to a total cost function because the assumption of cost minimizing production inputs is not met. That is, electric utilities are overcapitalized. Therefore, the optimal capital stock is estimated and an estimate of economies of scale is generated. Evidence suggests that firms are operating on the negatively sloped portion of …

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Dispersion Minimization In Capillary Electrochromatography: A Knox-Parcher Study On Packed Capillaries., Preston Charles Lowe Jan 1998

Dispersion Minimization In Capillary Electrochromatography: A Knox-Parcher Study On Packed Capillaries., Preston Charles Lowe

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electrochromatography (CEC), a hybrid of LC and CE, is a recent and fairly unexplored method of analysis, but has already been shown to be a very efficient separation technique. This thesis comprises a study of the Knox-Parcher effect and its influence upon CEC. The Knox-Parcher effect, which has been established in GC and LC, describes the dependence of reduced plate height, h, on the ratio, r, established by the ratio of the channel diameter (dc) to the particle diameter (dp). This study was conducted using particles with a diameter of 60 mm and capillaries having inner diameters ranging from 246 …

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