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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Numerical Simulation For Parametric Study Of A Two -Stroke Compression Ignition Direct Injection Linear Engine, Ehab F. Shoukry Aug 2003

Numerical Simulation For Parametric Study Of A Two -Stroke Compression Ignition Direct Injection Linear Engine, Ehab F. Shoukry

Graduate Theses, Dissertations, and Problem Reports (ETD)

A time based numerical simulation program was built at West Virginia University to simulate the operation of a two-stroke compression ignition direct injection linear engine. The two-stroke linear engine consists of two pistons connected together with a yoke and allowed to move freely according to the frequent combustion that takes place in response to fueling and load applied along the full stroke of the internal combustion engine. The simulating program used a series of dynamic and thermodynamic equations that were solved simultaneously to predict the performance and analyze the different factors affecting the operation of the two-stroke compression ignition linear …

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Fast Wavelet Collocation Methods For Second Kind Integral Equations On Polygons, Yi Wang Aug 2003

Fast Wavelet Collocation Methods For Second Kind Integral Equations On Polygons, Yi Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this thesis we develop fast wavelet collocation methods for integral equations of the second kind with weakly singular kernels over polygons . For this purpose, we construct multiscale wavelet functions and collocation functionals having vanishing moments. Moreover, we propose several truncation strategies, which lead to fast algorithms, for the coefficient matrix of the corresponding discrete system. Critical issues for numerical implementation of such methods are considered, such as choices of practical truncation strategies, numerical integration of weakly singular integrals, error controls of numerical quadrature and numerical solutions of resulting compressed linear systems. Numerical experiments are given to demonstrate proposed …

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Dowel-Concrete Contact Characteristics, Sri Vani Sirisha Motamarri Aug 2003

Dowel-Concrete Contact Characteristics, Sri Vani Sirisha Motamarri

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this thesis, the dowel-pulling force and the dowel-concrete coefficient of friction were measured using a novel laboratory setup of vibrating wire strain gauges embedded in both the dowel and concrete. The gages are set to measure the shrinkage strain induced in the concrete that surrounds the dowel as it cures causing the solidified concrete to clamp on the steel dowel. The measurements reveal that radial strain in concrete around the dowel is not uniform along the dowel circumference. As the dowel is pulled out of concrete, both the dowel-pulling force and the elastic strain recovery in concrete are recorded …

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Hydrology Of The Beaver Creek Watershed Using The Tr-20 Model And The Hec-Hms Program, Vijayalakshmi Tummala Aug 2003

Hydrology Of The Beaver Creek Watershed Using The Tr-20 Model And The Hec-Hms Program, Vijayalakshmi Tummala

Graduate Theses, Dissertations, and Problem Reports (ETD)

The proposed alignment of the Appalachian Corridor H section from Davis to Bismarck passes through Beaver Creek watershed, Tucker County, West Virginia, which was heavily affected by the historical mining, deteriorating the water quality conditions of the Beaver Creek. To improve the water quality of Beaver Creek, identification of the sources of impaired waters and the conveyance of these flows into passive treatment facilities for remediation has been proposed. To aid in the design of these treatment facilities, a baseline hydrology description through the hydrologic modeling of the watershed with the aid of rainfall-runoff models was proposed. The watershed modeling …

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Investigation Of The Applicability Of Neural-Fuzzy Logic Modeling For Culvert Hydrodynamics, Jonathan M. Lester Aug 2003

Investigation Of The Applicability Of Neural-Fuzzy Logic Modeling For Culvert Hydrodynamics, Jonathan M. Lester

Graduate Theses, Dissertations, and Problem Reports (ETD)

As a result of an earlier WV DOH study, the idea came to the forefront of using a completely new approach to analyzing the complex subject of culvert hydrodynamics. The literature indicates that there have been no reports of artificial intelligence, to include neural networks, fuzzy logic, or combined neural-fuzzy logic, used to investigate and predict culvert hydrodynamics.;The scope of this dissertation is to investigate the applicability of using neural-fuzzy logic to predict culvert diameters. To analyze these flows, commercial culvert software was employed to account for all types of flow conditions. This included different slopes, lengths, flow-rates, pipe sizes, …

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Evaluation Of A Whole-Class Token Economy To Manage Disruptive Behavior In Preschool Classrooms, Holly A. Filcheck Aug 2003

Evaluation Of A Whole-Class Token Economy To Manage Disruptive Behavior In Preschool Classrooms, Holly A. Filcheck

Graduate Theses, Dissertations, and Problem Reports (ETD)

The behavior of children in a preschool classroom was assessed to evaluate the effectiveness of two classroom management approaches: (a) strategies already employed by the teachers, and (b) the Level System. Strategies already employed by the teachers were those that they currently used in their preschool classroom. This phase was considered the baseline or "A" treatment phase. The Level System is a new program that utilizes strategies including a token economy, stimulating rewards, strategic attention, and labeled praise to manage a range of behaviors exhibited by children in the classroom. This was considered the "B" treatment condition. These two approaches …

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Modeling The International Competitiveness Of Botswana's Coal, Khaulani Fichani May 2003

Modeling The International Competitiveness Of Botswana's Coal, Khaulani Fichani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Botswana has vast proven deposits of steam coal, which for a long time it has wanted to develop but without much success. The main objectives of this study are: (1) to analyze the time schedule of coal exports likely to be forthcoming from Botswana and the land routes for these exports; (2) to determine the competitiveness of Botswana's coal in the world steam coal markets and (3) to make recommendations on the appropriate policy for the exploitation of this coal. To accomplish these objectives, we construct a model of the seaborne steam coal trade consisting of exporters and importers with …

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Conceptual And Application Issues In The Implementation Of Object-Oriented Gis, Janette Elizabeth Bennett May 2003

Conceptual And Application Issues In The Implementation Of Object-Oriented Gis, Janette Elizabeth Bennett

Graduate Theses, Dissertations, and Problem Reports (ETD)

The adoption of object-oriented technology for spatial data modeling is becoming a significant trend in GIS. This research explores the concepts of Object-Oriented GIS (OOGIS) and illustrates its versatility in two case studies. OOGIS provides a feature-based, intuitive representation of real world features. The study emphasizes the fundamental concepts of inheritance, polymorphism, and encapsulation in OOGIS and explores schema design, long transactions, and versioning. Further, the study discusses the advantages of OOGIS in the management and analysis of geospatial data. The case studies demonstrate both the conceptual basis of OOGIS and specific functionality including behavior, methods, versioning, long transactions and …

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Effects Of Artificial Neural Networks Characterization On Prediction Of Diesel Engine Emissions, Azadeh Tehranian May 2003

Effects Of Artificial Neural Networks Characterization On Prediction Of Diesel Engine Emissions, Azadeh Tehranian

Graduate Theses, Dissertations, and Problem Reports (ETD)

More than a century after its invention, diesel remains the fuel of choice for buses and freight trucks. Diesel exhaust contains three gases that are regulated by the United States Environmental Protection Agency (EPA), as well as particulate matter (PM). There is a societal need both to lower emissions and to predict or model emissions more accurately for inventory purposes. Engine modeling, and real time control are the most indispensable steps towards lowering engine emissions, and it is argued that this modeling can be achieved by implementation of Artificial Neural Networks (ANN). Effects of ANN design, architecture, and learning parameters …

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Modeling Of Product Variability In Fluidized Bed Coating Equipment, Ku Zilati Ku Shaari May 2003

Modeling Of Product Variability In Fluidized Bed Coating Equipment, Ku Zilati Ku Shaari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Particle coating in fluidized bed equipment is common practice for improving the properties of solid products, particularly in the pharmaceutical, food and agricultural industries. In this thesis, the application of particle coating to pharmaceutical products utilizing the Wurster-column coating process is addressed. This technique is extensively used in the pharmaceutical industry for precision drug coating and modified release coating of tablets and pellets.;The simulation of particle movement in fluidized beds has been successfully developed using Monte Carlo simulation. Raw velocity and voidage data for each region of a semicircular fluidized bed, obtained by Subramanian (2001), are used in the simulation. …

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Modeling And Controls For A Laser Glass Cutting Machine Workcell Robot, Asif Mushtaq Mohammad May 2003

Modeling And Controls For A Laser Glass Cutting Machine Workcell Robot, Asif Mushtaq Mohammad

Graduate Theses, Dissertations, and Problem Reports (ETD)

The SCARA (Selective Compliance Assembly Robot Arm)-Type Nimbl loader junior robot includes a four-degree of freedom robot manipulator arm. This thesis deals with three main areas of robot behavior: kinematics, dynamics and controls for the purpose of improving the performance of the Laser Glass Cutting Machine (LGCM) workcell. The thesis deals with developing kinematic and dynamic models of this robot arm and their application to task planning of this robot.;Task planning is done for SCARA-Type Nimbl loader robot, in which the robot starts from pick position to place position. A 4-3-4 joint trajectory was generated for pick-to-place path for the …

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Moisture Diffusion Through Neat And Glass-Fiber Reinforced Vinyl Ester Resin Containing Nanoclay, Hiteshkumar T. Rana May 2003

Moisture Diffusion Through Neat And Glass-Fiber Reinforced Vinyl Ester Resin Containing Nanoclay, Hiteshkumar T. Rana

Graduate Theses, Dissertations, and Problem Reports (ETD)

Moisture diffusion was studied through neat resin as well as glass-fiber reinforced vinyl ester samples, both containing up to 5 wt% montmorillonite clay. Transient and steady-state diffusion experiments were carried out with both neat resin as well as glass-fiber reinforced samples. Effect of saline and alkaline solutions on the process of diffusion was studied. It was found that the diffusivity decreased due to the presence of nanoclay in polymer. SEM images of FRPs were taken after two months of immersion in distilled water at room temperature. The SEM images revealed that the presence of clay indeed protected the glass-fibers. Effect …

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Modular Track Panels For Improved Safety In The Mining Transportation Industry, Donald Sterling Tusing May 2003

Modular Track Panels For Improved Safety In The Mining Transportation Industry, Donald Sterling Tusing

Graduate Theses, Dissertations, and Problem Reports (ETD)

Locomotives and "mine cars" often derail (often two or three times daily) in coalmines causing fatal injuries, fires initiated from sparks during derailment, and costly downtimes. Modular track panels (resembling the ladder track systems used in Japan) were designed and tested for bending behavior and load sharing characteristics, between track modules and also between rails, to improve safety of miners during transportation. Prefabricated track modules made of prestressed concrete and fiber reinforced polymer (FRP) composites were evaluated. Two modular prestressed concrete modules, each 15 ft long, were tested, as well as one set of prestressed concrete half-panels to test the …

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Development Of A Test Facility To Evaluate Hot Gas Filtration Characteristics Of A Candle Filter, Juan Pablo Rincon May 2003

Development Of A Test Facility To Evaluate Hot Gas Filtration Characteristics Of A Candle Filter, Juan Pablo Rincon

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hot gas particulate filtration is a basic component in advanced power generation systems such as Integrated Gasification Combined Cycle (IGCC) and Pressurized Fluidized Bed Combustion (PFBC). These systems require effective particulate removal to protect the downstream gas turbine and also to meet environmental emission requirements. The ceramic barrier filter is one of the options for hot gas filtration. Hot gases flow through ceramic candle filters depositing ash on the outer surface of the filter. After this cleaning process there may be some residual ash remaining on the filter surface. This residual ash layer may grow after many cycles of filtering, …

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Evaluation Of The Effect Of Fines On Asphalt Concrete, Carlos Humberto Reyes May 2003

Evaluation Of The Effect Of Fines On Asphalt Concrete, Carlos Humberto Reyes

Graduate Theses, Dissertations, and Problem Reports (ETD)

Several methods have been developed for determining the quantities of aggregate and asphalt cement used in asphalt concrete. This research consists of the evaluation of the surface area of different aggregates used in the state of West Virginia. This factor is important because the amount of asphalt needed to coat the aggregate depends on the specific surface area of the aggregate blend. The specific surface area of the aggregate blend is usually calculated based on the aggregate gradation and surface area factors.;This research proposes a method to obtain accurate specific surface area factors using the Blaine air permeability apparatus. By …

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Enhancing The Effectiveness Of The Utility Energy Supply Chain In Integrated Steel Manufacturing, Girish Sudhir Bhave May 2003

Enhancing The Effectiveness Of The Utility Energy Supply Chain In Integrated Steel Manufacturing, Girish Sudhir Bhave

Graduate Theses, Dissertations, and Problem Reports (ETD)

The iron and steel industry is energy intensive. The steel industry accounts for 2--3 of total US energy consumption. The energy costs account for 12--15% of the total cost of manufacturing steel. Cogeneration is done by most of the integrated steel producers for on-site electricity generation. The steel industries use different utility systems, and 90% of the industry uses standard steam boilers, steam turbines and BOP (Basic Oxygen Process). The boilers produce steam which is used for power generation and production processes. The system consumes oil, natural gas and blast furnace gas (BFG) to produce this steam and electricity. It …

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In Situ Determination Of Strength And Stiffness Of Structural Lumber And Composite Products, Jody D. Gray May 2003

In Situ Determination Of Strength And Stiffness Of Structural Lumber And Composite Products, Jody D. Gray

Graduate Theses, Dissertations, and Problem Reports (ETD)

Wood is prone to deterioration that reduces its load bearing capabilities. Periodically, older wooden members need to be inspected to ensure the strength and stability of the structure. Historically these inspection methods have consisted of visual inspections lacking scientific basis.;Non-destructive testing (NDT) methods were investigated by this research for the possibility of evaluating modulus of rupture and modulus of elasticity of built-in wooden members. Methods included stress wave timing for dynamic MOE determination and screw withdrawal force (SWF) for MOR and density prediction. Standard ASTM testing procedures were used to determine the actual properties and statistical relationships between these variables …

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Comparison Of Concentrations In The Breathing Zone, Santosh Raghavendra Kulkarni May 2003

Comparison Of Concentrations In The Breathing Zone, Santosh Raghavendra Kulkarni

Graduate Theses, Dissertations, and Problem Reports (ETD)

The concentrations in the "breathing zone" were analyzed on three human subjects in simulating work conditions. The experiments were carried out in a wind tunnel having 40&feet; x 12&feet; x 9&feet; dimensions. Ethanol vapor mixed with nitrogen was used as a tracer gas. Samples were taken at the forehead, adjacent to the nose (nose), the mouth, neck, chest, right lapel, left lapel. Nose was sampled at l liter per minute (lpm) and 0.15 lpm at different times, while the others were sampled at 0.15 lpm at two different wind tunnel velocities. The source was released at naval height for each …

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Adaptive Fault Diagnosis In Interactive Electronic Technical Manuals (Ietms), Rabih Faysal Kraidli May 2003

Adaptive Fault Diagnosis In Interactive Electronic Technical Manuals (Ietms), Rabih Faysal Kraidli

Graduate Theses, Dissertations, and Problem Reports (ETD)

An Interactive Electronic Technical Manual (IETM) is a technical manual that is prepared in digital format to provide information about the diagnostics and maintenance of complex systems.;In this thesis we present a methodology for adaptive fault diagnosis in IETMs, a methodology that constantly adapts the fault diagnosis procedure, according to the experience of the user performing the diagnosis. We develop a framework of adaptation that constantly monitors user behavior, and "learns" about the fault and its possible causes as the system is used, hence making it easier to perform such procedures, which increases efficiency of usage of such a manual, …

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Application Of Statistical Methods For "Flow Unit" Identification And Characterization Of A Reservoir Using Well Log And Core Data, Reza Mustafa May 2003

Application Of Statistical Methods For "Flow Unit" Identification And Characterization Of A Reservoir Using Well Log And Core Data, Reza Mustafa

Graduate Theses, Dissertations, and Problem Reports (ETD)

A flow unit is a stratigraphically continuous interval of similar reservoir process speed that maintains the geologic framework and characteristics of rock types. Permeability and porosity of the reservoir rock has always been considered as two of the most important parameters to identify flow unit for formation evaluation, reservoir description, and characterization. Beyond evaluating permeability and porosity, one can also use combinations of two or more rock properties to gain insight into the character of two through porous media. Porosity is commonly evaluated from the well log data, which are usually available from the most wells in the reservoir. But …

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Time, Temperature And Frequency Viscoelastic Behavior Of Commercial Polymers, Michael John Julius May 2003

Time, Temperature And Frequency Viscoelastic Behavior Of Commercial Polymers, Michael John Julius

Graduate Theses, Dissertations, and Problem Reports (ETD)

This work involves an experimental investigation of creep behavior of commercial polymers used as encased liners in deteriorated sewer pipelines with emphasis on characterizing the effects of physical aging, temperature, and frequency. The procedure for finding the shift rate, mu, is based on Struik's protocol. Time-temperature superposition (TTSP) of short-term data, at different temperatures, was done. Effective Time Theory (ETT) is used to find the effective time, lambda, as a function of real time, t, from the master curve obtained by TTSP. Dynamic Mechanical Analysis (DMA) tests were done to get complex relaxation modulus, E*(o), as a function of frequency. …

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Solidification Cracking Resistance Of High Strength Aluminum Alloys, Rohit K. Paramatmuni May 2003

Solidification Cracking Resistance Of High Strength Aluminum Alloys, Rohit K. Paramatmuni

Graduate Theses, Dissertations, and Problem Reports (ETD)

In Direct chill (DC) casting which is used in the manufacture of high strength aluminum alloys uneven cooling rates at different parts of the ingot cause thermal stresses. Due to these thermal stresses, cracks are initiated at the startup stage which may propagate as the stress elevates. Hence the evaluation of fracture toughness (cracking resistance) at different parts of ingot is very much essential to understand the propagation of cracks in ingots.;The objective of this research was to determine the cracking resistance of Al 2024 (Al-Cu-Mg) and Al 3004 (Al-Mn-Mg) alloys and to illustrate the relation of cooling rate during …

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Gender Differences In Test Anxiety, Angela Marie Josephine Fiore May 2003

Gender Differences In Test Anxiety, Angela Marie Josephine Fiore

Graduate Theses, Dissertations, and Problem Reports (ETD)

The research regarding overall general test anxiety and sex difference is contradictory at best. There is no clear answer to the research question concerning general test anxiety and sex difference according to the literature. An experiment using the modified Suinn Test Anxiety Behavior Scale (1971) was conducted to detect differences between the sexes with regard to test anxiety. There was no overall significant difference between the genders; however, when a multivariate regression was conducted to account for variability contributed by age and class, there was a statistically significant difference. This finding can be perceived as an indication that it is …

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Investigation Of Ship Wakes Using Les With Various Sgs Models, Zeynep N. Cehreli May 2003

Investigation Of Ship Wakes Using Les With Various Sgs Models, Zeynep N. Cehreli

Graduate Theses, Dissertations, and Problem Reports (ETD)

Turbulence plays an important role in ship wake flows. Without the knowledge of turbulent intensities and length scale information it is virtually impossible to model and predict turbulence characteristics in complex flows, such as ship wake flows. Moreover, the behavior of ship wakes requires an understanding of the turbulence near a free surface. The present study will focus on identifying the contributions of various mechanisms, but primarily that of the free surface, to the process of turbulence generation and dissipation in the wake of a turning ship using the large eddy simulation (LES) technique. LES is applied in conjunction with …

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Modeling Of An Aluminum Reduction Cell For The Development Of A State Estimator, Philip Biedler May 2003

Modeling Of An Aluminum Reduction Cell For The Development Of A State Estimator, Philip Biedler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electrolytic cells are used to produce aluminum from alumina ore. These cells use a carbon anode, a cryolitic bath, and a carbon containment vessel, which also serves as the cathode. The process is not completely understood because of the limited number of measurements and its complexity.;A finite element model was developed that simulates the electrical, thermal, and chemical phenomena occurring within the cell. The model was verified by comparing its output to data presented in the literature, and by comparing its output to data gathered from operating reduction cells at Century Aluminum in Ravenswood, WV. The model was used to …

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Measurement Of Attitude Toward Educational Use Of The Internet In An English Composition Course With A Comparison Of Traditional -Aged And Non-Traditional-Aged Students, Diana Gail Duran May 2003

Measurement Of Attitude Toward Educational Use Of The Internet In An English Composition Course With A Comparison Of Traditional -Aged And Non-Traditional-Aged Students, Diana Gail Duran

Graduate Theses, Dissertations, and Problem Reports (ETD)

Attitude is tied to behavior, and writing behaviors seem to be affected by using a computer. Technological advances have forever changed the way educators view the process of writing, including the way students learn, how they feel about the way they are learning, and their subsequent behaviors. Numerous studies have indicated that using computers to write changes the way students write, what they write, and the quantity and quality of that writing. However, studies disagreed about how these changes occur, whether they are positive or negative (or neither), and what psychological dynamics, such as attitude, are involved, to what degree, …

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Reinforcement And Punishment During Programmed Instruction, Stephen C. Scherer May 2003

Reinforcement And Punishment During Programmed Instruction, Stephen C. Scherer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recommendations for improving answer accuracy during programmed instruction have included the use of punishment to decrease the rate of students' responding and to prevent careless mistakes. The effects of punishment during programmed instruction, however, have not been clearly identified. There is evidence that punishment increases attention and decreases response rates during learning tasks, but other effects on student responding, including escape from the learning task, have not been systematically examined. The present study was designed to systematically examine the effects of punishment as well as extinction during programmed instruction. Four college students were recruited to earn money while working on …

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Mesomechanics Of Fabric Reinforced Composites, Thomas Miles Damiani May 2003

Mesomechanics Of Fabric Reinforced Composites, Thomas Miles Damiani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber reinforced plastic composites are an attractive alternative to traditional materials because of, among other things, the ability to concurrently design the materials and ratios to fit a specific need. One method of fiber reinforcement is through the used of woven fabrics, which provide more balanced overall strengths and durability during fabrication. The weaving and interlacing of the fibers, however, adds a level of complexity when predicting material properties and strengths using micromechanical models. Traditional models have mostly been based on classical thin lamination theory, and this method is limited in its scope and applicability for woven fabric composites. This …

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Implementation And Application Of Nde On Ceramic Candle Filters, Alejandro C. Kiriakidis May 2003

Implementation And Application Of Nde On Ceramic Candle Filters, Alejandro C. Kiriakidis

Graduate Theses, Dissertations, and Problem Reports (ETD)

A nondestructive evaluation (NDE) technique has been developed to determine the deterioration and remaining life of full-size ceramic candle filters used at the Power System Development Facility (PSDF) in Alabama. Ceramic candle filters are hollow cylindrical structures made of porous ceramic materials used in advanced coal-fired power generation systems. They protect power plant's gas turbine components from damage due to erosion. In general, advanced coal-fired power systems operational conditions include extreme thermal/pressure environment and vibration-induced stresses over a great period of time. The knowledge of the dynamic behavior of ceramic candle filters is essential and can be used to measure …

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Linear Expansion Of Dental Stone After Its Final Set And Beyond Two Hours, Marcos Cid Galano May 2003

Linear Expansion Of Dental Stone After Its Final Set And Beyond Two Hours, Marcos Cid Galano

Graduate Theses, Dissertations, and Problem Reports (ETD)

When accuracy and strength are required in fabricating working casts improved dental stones are recommended. The main variable affecting this accuracy is linear setting expansion. In this research study the linear setting expansion of three commonly used improved dental stones were compared over an extended 2-week period. Hard Rock, Silky Rock and Prima-Rock were vacuum mixed following manufacturers instructions. Five specimens of each stone were measured for linear expansion using a SAM EMI100 Expansion measuring Device. Expansion measurements were made at 10 and 30 minutes, 2, 24, 48, 72, and 120 hours. The gathered data were subjected to a two …

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