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Recharge Dynamics Of A Perched Phreatic Aquifer, Joseph Neil Ketchum Jr. Dec 1998

Recharge Dynamics Of A Perched Phreatic Aquifer, Joseph Neil Ketchum Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

Numerous techniques were used to analyze recharge rates, timing, and mechanisms for a perched, phreatic aquifer. Recharge rates were estimated using fluid mass balance (FMB), integrated hydrograph separation (IHS), and innovative hydrograph manipulation techniques. Timing and mechanisms of recharge were analyzed using signal-processing and linear-system approaches. Hydrometeorologic and hydrologic data were collected for a 16-month period (4/97 to 8/98) using both manual and automated techniques. Precipitation totaled 135.6 cm and evapotranspiration (ET) calculated using the Penman-Monteith method totaled 107.5 cm. Recharge estimates from FMB ranged from 20.3% to 33.6%. Springflows were modeled using a stage-discharge cross-correlation method. Recharge estimates from …

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Development And Validation Of A Modular Hybrid Electric Vehicle Simulation Model, William Frederick Kellermeyer Iii Dec 1998

Development And Validation Of A Modular Hybrid Electric Vehicle Simulation Model, William Frederick Kellermeyer Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

To attempt to bring rigor and analysis to the design process, accurate simulation programs are crucial. Most hybrid electric vehicle hybrid electric vehicle (HEV) simulation programs are written for very specific component configurations and only allow changes in component sizes. These programs prove helpful only if one designs a component configuration similar to the one already simulated. A modular based program such as the one developed here allows simpler reconfiguration of the components for an accurate simulation of almost any component configuration design. This HEV simulation program allows for simulation of all three types of hybrids, with several engine types …

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Acquisition Of Observing Responses With Delayed Conditioned Reinforcement, Gregory A. Lieving Dec 1998

Acquisition Of Observing Responses With Delayed Conditioned Reinforcement, Gregory A. Lieving

Graduate Theses, Dissertations, and Problem Reports (ETD)

Six pigeons were trained to key peck for 3-s access to mixed grain on a multiple variable-interval 60-s extinction schedule. The schedule then was changed to a mixed variable-interval 60-s extinction schedule. Simultaneously, a treadle was introduced into the chamber. For 3 pigeons, the stimulus correlated previously with the variable-interval schedule could be produced by treadle pressing (i.e., an observing response) on a tandem fixed-ratio 1 differential-reinforcement-of-other-behavior 10-s schedule. For the other 3 pigeons, no contingency was implemented for treadle pressing. Treadle pressing was established equally in the presence and absence of the observing contingency. The results did not extend …

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Two-Stroke Linear Engine, Subhash Nandkumar Dec 1998

Two-Stroke Linear Engine, Subhash Nandkumar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Linear, crankless, internal combustion engines may find application in the generation of electrical power without the need to convert linear to rotary motion. The elimination of the connecting rod and crankshaft can improve the efficiency of the engine significantly and the reduced weight and cost are added advantages. A linear, crankless, internal combustion engine prototype has been developed for electrical power generation in combination with a linear alternator. The operation of this engine is distinct from that of a conventional slider-crank mechanism engine, insofar as the motion of the two horizontally opposed pistons is not externally constrained. A two-stroke engine …

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Hydrothermal Aging Of Zeolite-Based Catalysts, Joongjai Panpranot Dec 1998

Hydrothermal Aging Of Zeolite-Based Catalysts, Joongjai Panpranot

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study the RE-USY (Davision GO-40) FCC catalyst, a composite of RE-USY zeolite and alumina-silica gel matrix, was treated hydrothermally under simulated FCC regenerator conditions in a laboratory scale fluidized bed. Fresh and steam-aged catalysts were characterized by surface area reduction using the nitrogen BET and t-Plot surface area methods. The surface morphology was apparent from the scanning electron photomicrographs. An irreversible deactivation kinetic model developed earlier by Gardner.; S0- S/S0 ns=Ks t was applied to account for changes of surface area of the zeolite component as a function of time on stream, temperature and steam partial pressure. The …

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Emissions Reduction Benefits Of Adapting Electronic Closed Loop Fueling Control On A Mechanically Controlled Spark-Ignited Engine, Frederick Scott Richmond Dec 1998

Emissions Reduction Benefits Of Adapting Electronic Closed Loop Fueling Control On A Mechanically Controlled Spark-Ignited Engine, Frederick Scott Richmond

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent government gaseous exhaust emissions regulations have been expanded to include a variety of mobile air pollution sources. Exhaust emissions from non-road engines have recently become a focus of Environmental Protection Agency (EPA) regulations. The term "non-road engines" covers many industrial and general aviation (GA) type engines that are currently unregulated. This study examines the gaseous exhaust gas emissions produced from a mechanically-controlled Lycoming IO-360-B GA engine and studies the benefits of conversion to electronic fuel injection with closed loop feedback control. The study concludes that the overall gaseous exhaust emissions from the unmodified engine far exceed current automotive standards. …

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Identification Of Math Anxiety Subtypes, Aline Elizabeth Rabalais Dec 1998

Identification Of Math Anxiety Subtypes, Aline Elizabeth Rabalais

Graduate Theses, Dissertations, and Problem Reports (ETD)

Conceptualizations of mathematics anxiety, as well as factors that are empirically related to it, were identified from the existing literature. These factors are test, evaluation, trait, and state anxiety, as well as gender and level of math ability. Differences in these factors were hypothesized to distinguish subtypes of highly math anxious individuals from one another. In order to determine whether subtypes exist, cluster analyses were performed on a sample of 96 highly math anxious college students. The results revealed three clusters distinguished by completion time on two versions of a math test and age. Furthermore, participants' responses on a variety …

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Semi-Automated Modeling Approaches To Route Selection In Gis, Binfei Chen Dec 1998

Semi-Automated Modeling Approaches To Route Selection In Gis, Binfei Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

As an alternative to traditional graphical intuitive approaches (GIA), a semi-automated modeling approach (SMA) can more efficiently identify linear routes by using powerful iterative and automated methods. In this research, two case studies were investigated to examine critical issues relating to the accuracy and effectiveness of raster-defined algorithmic approaches to linear route location. The results illustrate that different shortest-path algorithms do not necessarily result in markedly different linear routes. However, differing results can occur when using different neighboring-cell links in the cell-based route network construction. Cell-based algorithmic approaches in both Arc/Info and IDRISI software generate very similar results which are …

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Willingness To Pay For Industrial Recruitment: A Look At Local Decision-Maker Activity Versus Citizen Preference, Beth Ann Loy Dec 1998

Willingness To Pay For Industrial Recruitment: A Look At Local Decision-Maker Activity Versus Citizen Preference, Beth Ann Loy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Academic research in the area of economic development policy is overwhelmingly critical of industrial recruitment, recommending instead that resources be directed towards strategies such as business retention and expansion, fostering local entrepreneurship, and amenity development. This research moves beyond criticizing industrial recruitment policy and explores one potential reason, a high discount rate, for practitioners' reliance on recruitment over other available local development techniques. The research also investigates developer's probability of success for industrial recruitment as well as alternative development strategies and examines whether economic developer use of incentive packages to recruit local businesses is a rational decision, i.e., supported by …

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Fuzzy Reliability Modeling Of Distributed Client -Server Systems, Patrick Louis Cross Dec 1998

Fuzzy Reliability Modeling Of Distributed Client -Server Systems, Patrick Louis Cross

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the proliferation of client-server systems there is a need for new approaches to determine their reliability in the uncertain environment of the internet. The proposed methods analyze client-server reliability by accounting for uncertainties in the operational environment of the internet. The uncertainties are addressed with a fuzzy paradigm applied in a tractable, verifiable reliability model of client-server systems. For computer hardware, fuzzy sets were used to address vague reliability data using bi-state fuzzy probabilistic theories. For software and operating systems, fuzzy sets account for the uncertainties in bi-state failure data using fuzzy possibility theories. Client-server architectures, such as hypercubes, …

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Do Christian Schools Implement Long -Range Plans?, Steven L. Degeorge Dec 1998

Do Christian Schools Implement Long -Range Plans?, Steven L. Degeorge

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine long-range plans of schools accredited by the Association of Christian Schools International (ACSI) to determine whether evidence of implementation is present in administrators' job descriptions and evaluation documents.;Data were gathered through the use of a survey and by the collection and comparison of long-range plans, administrators! job descriptions, and evaluation documents. A second survey of board chairs was taken to determine the acceptance of the rational planning model presented and their attitudes toward implementation.;Thirty-two schools participated in the study, in which major points of the long-range plans were fisted on a chart. …

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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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Cellular Mechanisms Of Altered Neuronal Sensitivity In The Genetically Epilepsy-Prone Rat, Lance Russell Molnar Dec 1998

Cellular Mechanisms Of Altered Neuronal Sensitivity In The Genetically Epilepsy-Prone Rat, Lance Russell Molnar

Graduate Theses, Dissertations, and Problem Reports (ETD)

The genetically epilepsy-prone rat (GEPR) is an animal model of epilepsy which exhibits deficits in GABAergic neurotransmission in a variety of brain regions. However, the underlying cause for this deficit has yet to be described. The present studies were therefore performed in order to elucidate the mechanism(s) underlying this GABAergic deficit. To accomplish this task, electrophysiological recordings of Purkinje neurons in sagittal slices of the cerebellar vermis were performed. The initial aim was to compare the basic electrical membrane characteristics of Purkinje neurons from GEPR and control animals using standard intracellular recording techniques. These studies indicated that there is no …

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Characterization Of Diversity Of Fungi Forming Arbuscular Endomycorrhizae In Selected Plant Communities, Sidney Luiz Sturmer Dec 1998

Characterization Of Diversity Of Fungi Forming Arbuscular Endomycorrhizae In Selected Plant Communities, Sidney Luiz Sturmer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Knowledge of taxonomic and functional diversity of arbuscular mycorrhizal fungi (Glomales, Zygomycetes) is important in understanding the biology and ecology of such a widespread mycorrhizal symbiosis. More definitive criteria for grouping and ranking taxa were established by reinterpreting morphological characters in selected species of Glomus (Glomaceae) and Acaulospora and Entrophospora (Acaulosporaceae) based on spore ontogenesis. Members of both families shared some patterns, such as discrete stages of spore growth and differentiation in three phases, resulting in the formation of three possible character complexes: a spore wall, flexible inner walls, and a pregermination structure. Families differed in presence or absence of …

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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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Identifying The Type And Appropriateness Of The Evaluations Of Selected Agriculturally Related Science And Technology-Based Usaid Projects Conducted Between 1985 And 1995, Allen E. Bayles Dec 1998

Identifying The Type And Appropriateness Of The Evaluations Of Selected Agriculturally Related Science And Technology-Based Usaid Projects Conducted Between 1985 And 1995, Allen E. Bayles

Graduate Theses, Dissertations, and Problem Reports (ETD)

A review of the literature indicated that baseline data that described how and what were being evaluated at the project level by agencies involved in third world development had not been published. This was a descriptive study using content analysis of the available evaluative reports for the USAID projects involved with the transfer of agriculturally-related technology identified in the National Science Foundation research project, Assessing the Literature on the Benefits of External Science and Technology Aid Assistance to Developing Countries (Pytlik, Vasudevan, Bayles & Spitznogle, 1997).;The research concludes that impact evaluations were not being conducted at the project level. While …

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Perceptions Of Supervisory Behaviors And Supervisory Needs Among Licensed Speech-Language Pathology Assistants, Jean Suzanne Mead Dec 1998

Perceptions Of Supervisory Behaviors And Supervisory Needs Among Licensed Speech-Language Pathology Assistants, Jean Suzanne Mead

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to identify supervisory behaviors that occurred and the extent to which they were perceived as necessary during supervisory interactions between licensed speech-language pathology assistants (SLPAs) and their supervising speech-language pathologists (SLPs). Surveys were mailed to the 173 licensed SLPAs in Louisiana, who were the population for this study, requesting information about the supervision received. Eighty-eight (51%) completed and returned the survey.;The survey consisted of three parts. Part I contained 29 statements that were each rated twice using a Likert-type scale. The first rating indicated the extent to which supervisory behaviors occurred and the second …

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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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Generalizations Of Colorability And Connectivity Of Graphs, Xiankun Zhang Dec 1998

Generalizations Of Colorability And Connectivity Of Graphs, Xiankun Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Let G = (V, E) be a graph and A a non-trivial Abelian group, and let F( G, A) denote the set of all functions f : E (G) → A. Denote by D an orientation of E( G). Then G is A-colorable if and only if for every f ∈ F(G, A) there exists an A-coloring c: V( G) → A such that for every e = (x, y) ∈ E(G) (assumed to be directed from x to y), c( x)--c(y) ≠ f(e). We define the group chromatic number of c1 (G) to be the minimum number m for …

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Determining Perspectives Of Selected Disciplines Concerning The Nature Of Technology Within Classic Literature, Bryan Calvin Maser Dec 1998

Determining Perspectives Of Selected Disciplines Concerning The Nature Of Technology Within Classic Literature, Bryan Calvin Maser

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this research was to identify if there was a significant difference between the perspectives of selected disciplines with regard to the nature and history of technology. A content analysis of classic literature from multiple disciplines to determine perspectives concerning the nature of technology served as a basis for the development of a general semantic differential instrument. The instrument was administered to a given population yielding a conceptual scoring of perspectives. Scored concepts were then cross referenced to respective disciplines to determine if the degree of difference between disciplines was statistically significant.

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Inside Of Her, Amy Lynn Fair Dec 1998

Inside Of Her, Amy Lynn Fair

Graduate Theses, Dissertations, and Problem Reports (ETD)

Inside of Her is a collection of linked short stories and poems that illuminate the life of a young woman named Ginnie Mudrich who constantly feels manipulated by her mother, Violet, and her childhood friend Anna. Ginnie realizes their control when she becomes friends with a waitress named Madeline. Through this friendship, Ginnie realizes that although she is in her early thirties, she is, in many ways, still a child.

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Scale And Texture In Digital Image Classification, Christopher John Sebastian Ferro Dec 1998

Scale And Texture In Digital Image Classification, Christopher John Sebastian Ferro

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis is a theoretical and empirical study on textural properties of digital images. Spatial information exists at a hierarchy of scales and texture is a consequence of the objects in that hierarchy. Within-class texture results from the spatial arrangement of objects at the next finer level in the hierarchy than the informational class. Between-class texture results from spectral differences between adjacent classes and is most obvious near class edges, especially for smooth classes. In rough classes between-class variance may not differ much from within-class variance. Errors in classifications using texture, therefore, are most likely associated with, class edges; however, …

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Real-Time Multimedia-Based Education Through The Internet, Abhay Arun Bakshi Dec 1998

Real-Time Multimedia-Based Education Through The Internet, Abhay Arun Bakshi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The rapid advances in computer and communications technologies are challenging the American education systems to provide increased educational opportunities beyond the traditional geographic boundaries at a reasonable cost. Many educational institutions are answering this challenge by developing distance education programs. Distance education provides effective learning environment. An important requirement for effective distance education is the availability of continuous interactivity and immediate feedback. Over the Internet, synchronous sharing of multimedia content introduces unacceptable delays as network bandwidth is limited. In this thesis, the issue of Internet bandwidth is minimized and a novel system is developed for distance education using multimedia course …

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Computational Modeling Of Brittle Impact Erosion Mechanisms, Shanmuga Sundaram Balasubramaniyam Dec 1998

Computational Modeling Of Brittle Impact Erosion Mechanisms, Shanmuga Sundaram Balasubramaniyam

Graduate Theses, Dissertations, and Problem Reports (ETD)

Materials are subjected to an erosion-corrosion environment in a wide range of applications today. Elevated temperatures promote the formation of oxide layers in jet engines. In fluidized bed boilers, the bed materials and piping of slurries and caustic materials cause erosion and corrosion. The process of erosion-corrosion may result in material loss and damage. Proper analytical modeling of the erosion-corrosion processes validated by experiments is needed to estimate the extent of damage in the material.;Empirical relations are available in the literature for predicting the amount of material loss due to erosion. These are obtained by conducting large number of experiments. …

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Investigation Of A Paleocatena Across A Late Pennsylvanian Landscape Comprised Of Organic And Mineral Paleosols, Nick Fedorko Iii Dec 1998

Investigation Of A Paleocatena Across A Late Pennsylvanian Landscape Comprised Of Organic And Mineral Paleosols, Nick Fedorko Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

Exposures of the Pittsburgh coal bed, its seatearth, and correlative rocks at six sites along a 79 mile-long traverse from Morgantown, West Virginia south to near Burnsville, West Virginia comprise a paleocatena of organic and mineral paleosols formed on a coeval landscape. Northern sites were poorly drained leading to weakly developed Inceptisol profiles in the seatearth followed by thick accumulations of organic matter. More highly evolved profiles developed at the better drained sites to the south contain: highly leached, kaolinitic A horizons; slickensided horizons; subsurface accumulation of iron oxide; strong soil structure; in-situ clay production and translocation; and redoximorphic concentrations …

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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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Engine Instrumentation And Data Analysis For Ignition System Testing, William Joseph Chambers Dec 1998

Engine Instrumentation And Data Analysis For Ignition System Testing, William Joseph Chambers

Graduate Theses, Dissertations, and Problem Reports (ETD)

The charge ignition system is used to ignite the fuel-air mixture in the combustion chamber of a spark ignited internal combustion engine and is the subject of many ongoing research projects. As a means to quantify the performance of an ignition system, a 16 horsepower Briggs and Stratton V-twin engine has been instrumented and the necessary data analysis software developed. This test engine was used to monitor the performance of three different ignition sources. When the performance of these ignition sources was analyzed using the test engine, the differences in performance of the systems was evident in the calculated values …

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Impedance Effects Of Metallic Ground Plane On The Ctha Antenna, Tao Guan Dec 1998

Impedance Effects Of Metallic Ground Plane On The Ctha Antenna, Tao Guan

Graduate Theses, Dissertations, and Problem Reports (ETD)

As with the fast-paced development of the communication industry, antennas have become an indispensable part of daily life. However, everyone may have experienced the malfunction of a communication system or radio due to a nearby human body or building or automobile. Then comes the question of how adjacent objects influence the antenna. This thesis has concentrated on the study of these effects on the impedance of the CTHA (contrawound toroidal helical antenna).;The results of this study indicate the CTHA's input impedance changes as a damped sinusoid function of the distance between it and the metallic ground plane. For equivalent distances …

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Experimental And Modeling Studies On A Catalytic Packed Bed Membrane Reactor, Ashutosh G. Deshpande Dec 1998

Experimental And Modeling Studies On A Catalytic Packed Bed Membrane Reactor, Ashutosh G. Deshpande

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the present work, the effects of operating conditions in a catalytic packed bed membrane reactor were investigated with the reactant gases H 2 and CO flowing through the membrane tube, and an inert gas N 2 flowing on the outside. The reaction under study was methanol synthesis with BASF catalyst, and a gamma-alumina membrane with a nominal pore size of 40 A was used.;Preliminary experiments were carried out in the membrane reactor without any catalyst inside membrane to characterize it in terms of its flux, permeance, and selectivity of H2 over CO. Experiments were carried out in the packed …

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