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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Transfer Of Heart Rate Feedback Training To Reduce Heart Rate Response To Laboratory Tasks, Jeffrey Louis Goodie Dec 2001

Transfer Of Heart Rate Feedback Training To Reduce Heart Rate Response To Laboratory Tasks, Jeffrey Louis Goodie

Graduate Theses, Dissertations, and Problem Reports (ETD)

Researchers have demonstrated that individuals can successfully reduce their heart rate (HR) response to a stressor when provided with heart rate feedback. However, it is unclear whether individuals can transfer HR reduction skills to stressors not used during HR feedback training. The present study used a multiple baseline, single subject design to examine the transfer of HR feedback training among six individuals. Participants were provided with HR feedback training during the presentation of a videogame, a mental arithmetic challenge, and a hand grip task until the participants reduced their HR to within 4 bpm of their resting HR or until …

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Chords Of Longest Circuits Of Graphs, Xuechao Li Dec 2001

Chords Of Longest Circuits Of Graphs, Xuechao Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis is on a long standing open conjecture proposed by one of the most prominent mathematicians, Dr. C. Thomassen: Every longest circuit of 3-connected graph has a chord. In 1987, C. Q. Zhang proved that every longest circuit of a 3-connected planar graph G has a chord if G is cubic or if the minimum degree is at least 4. In 1997, Carsten Thomassen proved that every longest circuit of 3-connected cubic graph has a chord.;In this dissertation, we prove the following three independent partial results: (1) Every longest circuit of a 3-connected graph embedded in a projective plane …

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Optical Gradation For Crushed Limestone Aggregates, Ken Cheng Dec 2001

Optical Gradation For Crushed Limestone Aggregates, Ken Cheng

Graduate Theses, Dissertations, and Problem Reports (ETD)

The strength and durability of asphalt pavement is directly affected by the characteristics of its main ingredient, mineral aggregate. Besides material strength, research has shown that mixture properties such as particle shape and mixture gradation have a significant affect on the quality of the asphalt concrete. A standard called "Superpave" has been developed which sets forth specifications for material selection and methods for measurement of aggregate properties. These standards require monitoring of aggregate properties, particularly gradation. In this dissertation, the feasibility of developing an optically based method for determining aggregate gradation was explored. The physical system primarily consists of a …

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Hybrid Arq With Parallel And Serial Concatenated Convolutional Codes For Next Generation Wireless Communications, Naveen Chandran Aug 2001

Hybrid Arq With Parallel And Serial Concatenated Convolutional Codes For Next Generation Wireless Communications, Naveen Chandran

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research focuses on evaluating the currently used FEC encoding-decoding schemes and improving the performance of error control systems by incorporating these schemes in a hybrid FEC-ARQ environment. Beginning with an overview of wireless communications and the various ARQ protocols, the thesis provides an in-depth explanation of convolutional encoding and Viterbi decoding, turbo (PCCC) and serial concatenated convolutional (SCCC) encoding with their respective MAP decoding strategies.;A type-II hybrid ARQ scheme with SCCCs is proposed for the first time and is a major contribution of this thesis. A vast improvement is seen in the BER performance of the successive individual FEC …

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Set-Theoretic And Algebraic Properties Of Certain Families Of Real Functions, Krzysztof Plotka Aug 2001

Set-Theoretic And Algebraic Properties Of Certain Families Of Real Functions, Krzysztof Plotka

Graduate Theses, Dissertations, and Problem Reports (ETD)

Given two families of real functions F1 and F2 we consider the following question: can every real function f be represented as f = f 1 + f2, where f1 and f2 belong to F1 and F2 , respectively? This question leads to the definition of the cardinal function Add: Add( F1,F2 ) is the smallest cardinality of a family F of functions for which there is no function g in F1 such that g + F is contained in F2 . This work is devoted entirely to the study of the function Add for different pairs of families of …

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Integrated Modulation Of Sympathetic Tone In The Microcirculation By Oxygen, Adenosine, And Nitric Oxide, Bryan Auston Sauls Aug 2001

Integrated Modulation Of Sympathetic Tone In The Microcirculation By Oxygen, Adenosine, And Nitric Oxide, Bryan Auston Sauls

Graduate Theses, Dissertations, and Problem Reports (ETD)

Despite a profound reduction in hemodynamic shear stress, a sustained release of endothelium-derived nitric oxide (NO) limits arteriolar constriction during periods of increased sympathetic nerve activity in the rat small intestine. In this project, we sought to test the hypothesis that adenosine, formed in response to a flow-dependent fall in local PO2, serves as the stimulus to preserve endothelial NO release under these conditions. Sympathetic nerve stimulation induced frequency-dependent arteriolar constrictions and a flow-dependent fall in local PO2. The arteriolar responses to nerve stimulation were enhanced after inhibition of NO synthase with NG-monomethyl-L-arginine (L-NMMA). Under a high (20%) O2 superfusate, …

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Numerical Modeling Of Cold Flow And Hot Gas Desulfurization In A Circulating Fluidized Bed, Neeraj N. Pugalia Aug 2001

Numerical Modeling Of Cold Flow And Hot Gas Desulfurization In A Circulating Fluidized Bed, Neeraj N. Pugalia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Section I. This work was carried out to understand the behavior of the solid and gas phases in a CFB riser. Only the riser is modeled as a straight pipe. A model with linear algebraic approximation to solids viscosity of the form, mus = 5.34epsilons, (epsilon s is the solids volume fraction) with an appropriate boundary condition at the wall obtained by approximate momentum balance solution at the wall to account for the solids recirculation is tested against experimental results. The work done was to predict the flow patterns in the CFB risers from available experimental data, including data from …

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Green-Ampt Infiltration Model Parameter Determination Using Scs Curve Number (Cn) And Soil Texture Class, And Application To The Scs Runoff Model, Elena Viktorovna Brevnova Aug 2001

Green-Ampt Infiltration Model Parameter Determination Using Scs Curve Number (Cn) And Soil Texture Class, And Application To The Scs Runoff Model, Elena Viktorovna Brevnova

Graduate Theses, Dissertations, and Problem Reports (ETD)

The U.S. Department of Agriculture (USDA) Soil Conservation Service Curve Number (SCS CN) method is a simple and widely popular technique of estimation of direct runoff volume for design and natural rainfall events in small watersheds. The SCS CN procedure is incorporated into such computer programs as TR-20 and TR-55. Although the method reliably predicts 24-hr runoff volume, the predicted distribution of runoff during a storm event is not realistic. This shortcoming of the SCS CN method is due to weakness in the infiltration concept of the method. Use of a physically realistic and distributed Green-Ampt infiltration model can significantly …

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Design And Analysis Of A Hybrid Steel/Composite Pipe For High-Pressure Applications, William Jennings Briers Iii Aug 2001

Design And Analysis Of A Hybrid Steel/Composite Pipe For High-Pressure Applications, William Jennings Briers Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

Once limited almost exclusively to aerospace applications, the use of composite materials has become widespread among many high performance industries. Today's petroleum industry is requiring piping systems to sustain high pressures, impact, rugged handling, and harsh environmental conditions such as corrosion and temperature. Advances in the last decade of engineered materials have opened the way for more conversions from metal to composites.;The objective of this research is to develop a lightweight composite pipe that meets the performance requirements of an existing high-pressure steel pipe. This development is crucial to the petroleum industry where hydraulic-fracturing services are demanding lighter weight materials …

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Green Tea Antioxidants Inhibition Of Oxidation And Mutation, Paul Stout Mcconnell Aug 2001

Green Tea Antioxidants Inhibition Of Oxidation And Mutation, Paul Stout Mcconnell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Green tea is a complex mixture containing several major potent antioxidants e.g., flavins and/or polyphenols. These antioxidants in green tea may react directly or indirectly with strong oxidizers e.g. peroxynitrite or its constituents (superoxide or nitric oxide). Green tea antioxidants can destroy the oxidants. Based on a simple chemical interaction of peroxynitrite (OONO-) and luminol, blue light is produced upon oxidation. It was shown that green tea and constituents have light inhibitory capabilities. In order to show the possible beneficial effects of green tea with DNA, plasmids were chosen to determine whether or not green tea was also capable of …

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Dynamic Coloring Of Graphs, Bruce Montgomery Aug 2001

Dynamic Coloring Of Graphs, Bruce Montgomery

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this dissertation, we introduce and study the idea of a dynamic coloring of a graph, a coloring in which any multiple-degree vertex of the graph must be adjacent to at least two color classes.;As parts of the overall research, we study (for some interesting subjects of colorings) the corresponding subjects of dynamic colorings, we compare the chromatic number and dynamic chromatic number, and we study some problems unique to dynamic colorings. Also, we introduce and briefly study a generalization of dynamic coloring.;The interesting subjects of colorings we consider are the chromatic number of important graphs, upper bounds of the …

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Simulation Based Modeling Of The Elastic Properties Of Structural Wood Based Composite Lumber, Laszlo Bejo Aug 2001

Simulation Based Modeling Of The Elastic Properties Of Structural Wood Based Composite Lumber, Laszlo Bejo

Graduate Theses, Dissertations, and Problem Reports (ETD)

The importance of wood-based composite lumber is increasing in the US market for construction materials. Manufacturers of such composites strive to make their products more competitive by increasing their value. This dissertation describes the development of simulation models that can aid these efforts by estimating the elastic characteristics of composite lumber products. The study included the assessment of the orthotropic mechanical properties of the raw material, the effect of densification it experiences during the hot-pressing procedure, and the geometric structure of the composites. Using the results of these investigations, computer models were created based on principles of deterministic and stochastic …

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Factors Contributing To College Freshmen Placed On Academic Probation, Lee Ann Vecellio Aug 2001

Factors Contributing To College Freshmen Placed On Academic Probation, Lee Ann Vecellio

Graduate Theses, Dissertations, and Problem Reports (ETD)

The responses of college freshmen placed on academic probation to a survey examining the factors leading to their poor academic performance were studied to ascertain the perceived problem areas. One hundred and seventy-two college freshmen selected factors concerning motivation, time management, social, and financial components, which they believed contributed to their poor academic performance during their freshman year. For males, inadequate balance between time and other activities was perceived as the number one factor contributing to their demise. On the other hand, females selected lack of academic motivation as their number one factor. Interestingly, these factors were reversed when identifying …

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Changes In Stand Structure And Species Diversity Following Clearcutting In Central Appalachian Hardwoods, Mark Benjamin Brashears Aug 2001

Changes In Stand Structure And Species Diversity Following Clearcutting In Central Appalachian Hardwoods, Mark Benjamin Brashears

Graduate Theses, Dissertations, and Problem Reports (ETD)

The clearcutting of second-growth Appalachian hardwood forests may cause a reduction in species diversity of the new cohort. This study measured changes in species composition, diversity, and stand structural characteristics following clearcutting of a second-growth hardwood forest. To evaluate the temporal changes in importance of central Appalachian hardwood tree species, thirteen clearcuts on good excellent sites in West Virginia were inventoried before harvesting and 2--26 years after harvesting. Shannon-Weaver's diversity index (H'), Pielou's evenness index (E), and species richness (S) were calculated before and after clearcutting. Species diversity and evenness has decreased, and species richness has remained stable following clearcutting. …

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Static And Dynamic Inventory Models Under Inflation, Time Value Of Money And Permissible Delay In Payment, Babak Khorrami Aug 2001

Static And Dynamic Inventory Models Under Inflation, Time Value Of Money And Permissible Delay In Payment, Babak Khorrami

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research a number of mathematical models were developed for static and dynamic deterministic single-item inventory systems. Economic factors such as inflation, time value of money and permissible delay in payment were considered in developing the models. Nonlinear optimization techniques were used to obtain the optimal policies for the systems.;First, a static single-item inventory model was considered in which shortages are allowed and a delay is permitted in payment. In this case, suppliers allow the customers to settle their accounts after a fixed delay period during which no interest is charged.;An extension of the model was then considered in …

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Mobile Agent-Based Attack-Resistant Architecture For Distributed Intrusion Detection System, Sentil Kumar Selliah Aug 2001

Mobile Agent-Based Attack-Resistant Architecture For Distributed Intrusion Detection System, Sentil Kumar Selliah

Graduate Theses, Dissertations, and Problem Reports (ETD)

The majority of the Distributed Intrusion Detection systems lack measures for providing security and integrity to their own components. The hierarchical organization and the static nature of the intrusion detection components in a largely distributed environment make them the likely targets of attacks. By disabling few operationally critical components along the hierarchy, an attacker can succeed in disabling the system's capability to correctly detect intrusions. One solution to this problem is to eliminate the system components' static nature by wrapping them as mobile agents. Through mobility we achieve an attack resistant architecture for the hierarchical distributed intrusion detection components. As …

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Modeling And Control Of A Wind Turbine As A Distributed Resource In An Electric Power System, Bongani Malinga Aug 2001

Modeling And Control Of A Wind Turbine As A Distributed Resource In An Electric Power System, Bongani Malinga

Graduate Theses, Dissertations, and Problem Reports (ETD)

Deregulation of electric utilities has led to consideration of new distributed resources (DRs) such as wind turbines. The DR dynamics have to be studied carefully to avoid unpredictable outputs and unknown interferences as well as to make sure that consistent and efficient power is supplied according to the load requirements.;The objective of this thesis is to make a contribution to the ongoing wind turbine research in the areas of modeling, control and implementation of wind turbines as DRs in deregulated electric power systems. A model of complete open-loop wind turbine system consisting of a rotor, a gearbox and a three-phase …

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Numerical Model For Determining The Wetting Front In A Clay Layer Of A Leaking Composite Barrier, Mustafa Eftelioglu Aug 2001

Numerical Model For Determining The Wetting Front In A Clay Layer Of A Leaking Composite Barrier, Mustafa Eftelioglu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Composite barriers for hazardous and solid waste landfills are designed to minimize hydraulic transport of the contaminant leachate of the landfill; however, the geomembrane can be damaged during construction or otherwise contain imperfections from manufacturing. It is desirable to estimate the discharge characteristics and the flow width of such a leachate should leaks in the geomembrane occur.;Numerical solutions of the flow equations for unsaturated soil barriers can provide an understanding of the movement of a leachate through a composite barrier. The purpose of this investigation was to develop a computer model that simulated two-dimensional migration of leachate beneath holes in …

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Damage Mechanics Of Human Cortical Bone, Gagik Parsam Parsamian Aug 2001

Damage Mechanics Of Human Cortical Bone, Gagik Parsam Parsamian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Skeletal fragility is an important orthopedic concern including the prevention of osteoporosis, long-term stability of prosthetic implants and stress fractures. Damage in human cortical bone has been implicated as a cause of increased fragility and is thought to initiate bone remodeling. Therefore, characterization of the mechanisms of damage initiation and accumulation in bone is challenging not only from the engineering prospective but also has a potential of revealing new insights in its physiology. The main objectives of this dissertation work were to study the early stages of damage development in human cortical bone and develop a constitutive formulation describing damage …

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Nondestructive Testing Of Reinforced And Prestressed Concrete Structures Using Acoustic Waveguides, Komwut Wissawapaisal Aug 2001

Nondestructive Testing Of Reinforced And Prestressed Concrete Structures Using Acoustic Waveguides, Komwut Wissawapaisal

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main objective of this research is to develop both passive and active nondestructive testing techniques for reinforced and prestressed concrete structures using acoustic waveguides. The first technique introduces a two-dimensional surface waveguide to enlarge the acoustic emission (AE) monitoring area of a reinforced concrete structure. A two-dimensional steel wire system is developed as an acoustic waveguide to study the AE behavior of a reinforced concrete floor slab. AE sensors are mounted to the end of the waveguides to detect AE signals, which are generated by pencil-lead breaks at various locations on concrete surface. Results show that the use of …

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Software Tool For Reliability Estimation, Manish Jhunjhunwala May 2001

Software Tool For Reliability Estimation, Manish Jhunjhunwala

Graduate Theses, Dissertations, and Problem Reports (ETD)

Reliability engineering is now an essential part of product development. In the area of electronics, reliability needs to be checked for each critical component before the product is shipped. Electronic products can range from computers to pace makers.;Over the years, several tools have been developed to estimate hardware/software reliability. Typically, such tools are either for hardware or software. This thesis presents a Software Tool for Reliability Estimation (STORE), which can be used for hardware components, software components, and for systems having both hardware and software components.;The objective of this research was to study several hardware-software reliability models, existing algorithms to …

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Stress Concentration Around Dowel Bars In Jointed Rigid Concrete Pavements, Mourad Youssef Riad May 2001

Stress Concentration Around Dowel Bars In Jointed Rigid Concrete Pavements, Mourad Youssef Riad

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study, the magnitude and state of stresses induced around dowel bars were identified through detailed 3D Finite Element (3DFE) modeling of dowel jointed rigid pavement structures. Both straight and skewed joints were modeled using extremely fine meshing that allows accurate modeling of the friction and separation at dowel concrete interfaces. The model response was examined for the case of joint loading with an equivalent axle load of 18000 lb. It was found that significantly large tensile stresses develop in the concrete on both sides of the loaded dowel. The magnitude of the tensile stress approaches the tensile modulus …

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Metaphysical Detectives And Postmodern Spaces, Or The Case Of The Missing Boundaries, Richard A. Swope May 2001

Metaphysical Detectives And Postmodern Spaces, Or The Case Of The Missing Boundaries, Richard A. Swope

Graduate Theses, Dissertations, and Problem Reports (ETD)

Taking as its point of departure Henri Lefebvre's contention that "(Social) space is a (social) product," my dissertation explores the contemporary American novels of Pynchon, Acker, Reed, Auster, DeLillo, and McElroy as well as the two recent films Dark City and The Thirteenth Floor and their dramatization of the production of twentieth-century social space. I approach these works as metaphysical detective stories which evoke the classic detective figure only to frustrate his impulse to solve and contain. Following Foucault's contention that "space is fundamental to any exercise of power," I suggest that the detective figure is significant to an understanding …

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Using Virtual Reality For Requirements Validation, Dejan Desovski May 2001

Using Virtual Reality For Requirements Validation, Dejan Desovski

Graduate Theses, Dissertations, and Problem Reports (ETD)

Failures of high consequence systems are intolerable. Studies have shown that a significant percentage of safety problems can be traced back to errors in the specification. An important problem that arises during validation is how to include a domain expert in this process. Although the domain experts have exclusive knowledge about the system operation, they may not understand formalisms used for system specification.;Essential type of "evidence" of the correctness of the formalization process must be provided by human-based calculation. Human calculation can be significantly amplified by shifting from symbolic representation to graphical representations. This, in turn, provides an environment for …

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Pattern Recognition In Software Engineering Trend Adapting, Dapeng Chen May 2001

Pattern Recognition In Software Engineering Trend Adapting, Dapeng Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Whether and when to adapt to certain software engineering trends are difficult questions to be answered by many decision-makers. The main reasons are due to the fact that evolution of software engineering trends itself is determined by various factors, many of which come from the fields outside of the software technology, thus hard to predict. So it is even harder to estimate the cost and benefit when adapting to certain trends. This paper is intended to study ways to decrease the risk involved in such decision making processes, by developing a pattern from past software engineering trends. While the pattern …

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Relationships And Differences On Self -Regulated Learning, Parental Involvement, Homework, And Academic Achievement, Among High School Students In Rural West Virginia, Samuel R. Heastie May 2001

Relationships And Differences On Self -Regulated Learning, Parental Involvement, Homework, And Academic Achievement, Among High School Students In Rural West Virginia, Samuel R. Heastie

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine the relationships among self-regulated learning (SRL), parental involvement (PI), homework (HW), and cumulative grade point average (CGPA), and the differences between gender on these variables for high school students in rural West Virginia. Research was conducted at a rural high school, grades nine through 12, in North Central West Virginia. Participants in the study comprised of 50 students and 35 parents, for a combined total of 85 participants. Data were collected for students and parents from teachers' grade book, students' records, and two survey instruments---Bandura's Children's Self-Efficacy Scale (1990) and The Parent …

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Student Variables As A Predictor Of E -Course Completion, Norma Helen Hodge-Thompson May 2001

Student Variables As A Predictor Of E -Course Completion, Norma Helen Hodge-Thompson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study is to determine student variables that predict E-course completion. Research questions were defined for investigating the relationship between student demographics and E-course completion. Student demographics include age, gender, GPA, student major, access to technology and employment. The student demographic variables were correlated with course completion and through logistic regression were determined to be predictors of E-course completion. The research population for this study was 3453 Marshall University students enrolled in E-courses from the spring semester of 1998 through the fall semester of 2000. Data for the study was obtained from the Marshall University Institutional Research …

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Essays On The Restructuring Of The Electricity Industry In The United States, Vladimir V. Starkov May 2001

Essays On The Restructuring Of The Electricity Industry In The United States, Vladimir V. Starkov

Graduate Theses, Dissertations, and Problem Reports (ETD)

The dissertation explores several issues that arise from the restructuring of the American electricity industry. The first chapter discusses economic reasons for deregulation, describes possible deregulation scenarios, and outlines potential pitfalls of deregulation.;Chapter 2 develops a forecast of electricity prices after the transition to retail competition. The equilibrium prices are found from an n -firm Cournot model of oligopoly with non-uniform marginal costs. It is further shown how the translog cost function can be used in the traditional solution of the Cournot model. Major empirical findings include marginal cost functions of every producer and forecast prices of electricity after deregulation …

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Nonlinear Transient And Steady State Analysis For Self-Excited Single-Phase Synchronous Reluctance Generator, Jingdong Chen May 2001

Nonlinear Transient And Steady State Analysis For Self-Excited Single-Phase Synchronous Reluctance Generator, Jingdong Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

With today's trend for distributed generation and the need for alternative and renewable energy sources, self-excited induction and synchronous reluctance generators have attracted more attention for wind, tidal and hydro power generation applications. Compared to synchronous and DC generators, they have the advantages: they are brushless, they are robust, they do not need DC excitation and they are relatively low cost.;Compared with SEIG, the self-excited reluctance generator (SERG) not only has the advantages of simplicity and ruggedness, but can also have enhanced steady-state characteristics and high efficiency over a wide range of operation. Moreover, its output frequency is determined only …

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Message Sequence Chart Specifications With Cross Verification, Timothy Shawn Boles May 2001

Message Sequence Chart Specifications With Cross Verification, Timothy Shawn Boles

Graduate Theses, Dissertations, and Problem Reports (ETD)

Current software specification verification methods are usually performed within the context of the specification method. There is little cross verification, pitting one type of specification against another, taking place. The most common techniques involve syntax checks across specifications or doing specification transformations and running verification within the new context. Since viewpoints of a system are different even within programming teams we concentrate on producing an efficient way to run cross verification on specifications, particularly specifications written with Message Sequence Charts and State Transition Diagrams.;In this work an algorithm is proposed in which all conditional MSCs are transformed into an algebraic …

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