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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Effect Of Moisture And Temperature On The Mechanical Properties Of Concrete, Brian Downie Aug 2005

Effect Of Moisture And Temperature On The Mechanical Properties Of Concrete, Brian Downie

Graduate Theses, Dissertations, and Problem Reports (ETD)

Concrete is one of the most widely used building materials. Extensive research was accomplished testing concrete properties including but not limited to modulus of elasticity, compressive strength, tensile strength, and Poisson's ratio using modulus of elasticity and strength testing. The research was done under laboratory conditions. The ideal air temperature in the laboratory was between 68 and 71 °F, and the ideal air relative humidity in a laboratory was between 40 and 60 percent. Research was accomplished on properties of concrete during the curing process at extreme temperatures experienced in the developed world, but little on concrete that is already …

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Microcontroller-Based Power Regulation For Induction Motors With Power Quality Conditioning, Joshua Scott Robinson Aug 2005

Microcontroller-Based Power Regulation For Induction Motors With Power Quality Conditioning, Joshua Scott Robinson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The focus of this thesis is to verify the power-saving characteristics of a triac-based motor controller and reduce the harmonics associated with the device by integrating a power quality conditioner. A hardware prototype of a motor controller was constructed using a microcontroller to detect the load magnitude and fire a triac accordingly. Test results showed an average decrease in active power consumption of 23.2% with a 426.6% average increase in harmonic distortion; the largest power savings occurred with light loads. A Simulink model of a line conditioner was created, verified, and adapted to utilize a digital controller. This conditioner uses …

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Water Quality Disturbances In An Aquaculture That Utilizes Treated Mine Water, Mark Wayne Smith Aug 2005

Water Quality Disturbances In An Aquaculture That Utilizes Treated Mine Water, Mark Wayne Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objectives of this study were to compare the performance of two feed treatments on a population of rainbow trout, Oncorhynchus mykiss, reared in a linear raceway system, which utilized mine water from a mine water treatment facility (MWTF); to measure and compare waste outputs; to monitor the water quality of the system; and to identify the impacts, if any, of the water quality on the fish population. Toward the end of the study, a spike in the turbidity of the water source led to additional objectives. First, the water quality was characterized during the events to determine the extent …

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Error Propagation Metrics From Xmi, Cihan Varol Aug 2005

Error Propagation Metrics From Xmi, Cihan Varol

Graduate Theses, Dissertations, and Problem Reports (ETD)

This work describes the production of an application Error Propagation Metrics from XMI which can extract process and display software design metrics from XMI files. The tool archives these design metrics in a standard XML format defined by a metric document type definition.;XMI is a flavour of XML allowing the description of UML models. As such, the XMI representation of a software design will include information from which a variety of software design metrics can be extracted. These metrics are potentially useful in improving the software design process, either throughout the early stages of design if a suitable XMI-enabled modelling …

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Effect Of Liquid Rheology On Jetting Of Polymer Solutions, Long Han Aug 2005

Effect Of Liquid Rheology On Jetting Of Polymer Solutions, Long Han

Graduate Theses, Dissertations, and Problem Reports (ETD)

Light Emitting Devices (LEDs) containing conjugated polymers are fabricated using ink jet printing. A common problem in the processing of these materials is that the Newtonian viscosity of the polymer solution is not sufficient to describe the jetting performance, because the molecular weights and concentrations employed are such that the resulting solutions are elastic. These differences in fluid elasticity levels cannot be measured using traditional techniques like dynamic mechanical experiments or the first normal stress difference in shear, but they strongly impact the jetting behavior of the liquid. Here, a polystyrene-DECALIN system has been formulated, and the level of elasticity …

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The Use Of Heuristics In Identifying Self-Propagating Malicious Mobile Code, Jesse Twardus Aug 2005

The Use Of Heuristics In Identifying Self-Propagating Malicious Mobile Code, Jesse Twardus

Graduate Theses, Dissertations, and Problem Reports (ETD)

Self-propagating malicious mobile code, or worms, has become a major threat to modern computer systems. As these types of viruses thrive in a networked computing environment, they have exploded in popularity in recent years.;Modern defenses have proved inadequate in protecting computer systems from the worm threat. The most often used remedy is a signature-based detection system that scans each incoming network packet for the presence of a signature identifying a specific worm. As a new worm or variant of an existing worm is released, this signature set must be updated to include definitions for the new worm or variant.;In this …

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The Effect Of Low And High Fertility Treatments On Soil Quality, Yields, Pest Incidence And Labor Requirements Of A Post-Transitional Organic Market Garden System, Todd Bradley Childers Aug 2005

The Effect Of Low And High Fertility Treatments On Soil Quality, Yields, Pest Incidence And Labor Requirements Of A Post-Transitional Organic Market Garden System, Todd Bradley Childers

Graduate Theses, Dissertations, and Problem Reports (ETD)

In a two-year study, eight vegetable crops were grown as part of a certified organic four-year crop rotation. High input plots received off-farm composted cow manure and cover crops, and low input plots were managed with the use of cover crops only. High input plots produced higher yields than low input plots in all crops, except peas, which yielded higher in low input plots. Soil organic matter levels were significantly higher in the high input than the low input plots and increased from 2003 to 2004 in both treatments. Available soil phosphorus levels in the high input plots were excessive, …

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Nondestructive Evaluation Of Wooden Logs Using Ground Penetrating Radar, Sachin Agrawal Aug 2005

Nondestructive Evaluation Of Wooden Logs Using Ground Penetrating Radar, Sachin Agrawal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Presently there are no suitable non-invasive methods for precisely detecting the subsurface defects in logs in real time. Internal defects such as knots, decays, and embedded metals are of greatest concern for lumber production. While defects such as knots and decays (rots) are of major concern related to productivity and yield of high value wood products, embedded metals can damage the saw blade and significantly increase the down time and maintenance costs of saw mills.;Nondestructive scanning of logs using techniques such as Ground Penetrating Radar (GPR) prior to sawing can greatly increase the productivity and yield of high value lumber. …

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The Design Of A Rotor Blade Test Facility, Jason W. Gill Aug 2005

The Design Of A Rotor Blade Test Facility, Jason W. Gill

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Mechanical and Aerospace Engineering Department has developed a need for test facilities related to rotorcraft, specifically facilities capable of testing scaled rotorcraft models and experimental propellers and rotors. A design was completed to fill these needs.;The design included several factors; aerodynamic conditions during operation, flexibility of application, ease and cost of construction, and safety. The aerodynamic conditions involved in the testing of rotors or propellers in static conditions were investigated. Other testing involving downwash impingement on wings was considered and incorporated into the design.;In addition, the design of the power transmission components was completed. This included the power requirements …

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The Biological Control Potential Of Cryphonectria Parasitica Strains Containing An Infectious Cdna Copy Of Hypovirus Chv1-Euro7, William R. Rittenour Aug 2005

The Biological Control Potential Of Cryphonectria Parasitica Strains Containing An Infectious Cdna Copy Of Hypovirus Chv1-Euro7, William R. Rittenour

Graduate Theses, Dissertations, and Problem Reports (ETD)

Transmissible hypovirulence has not become established in most areas of North America as it has in Europe where it has been associated with increased biological control of chestnut blight. Transgenic strains of Cryphonectria parasitica provide several mechanisms that may improve biological control. This study was designed to evaluate whether transgenic C. parasitica strains containing a cDNA transgene encoding the viral genome of CHV1-Euro7 show greater potential to biologically control blight than their cytoplasmically infected counterparts. Three treatments were employed that compared: transgenic hypovirulent strains (TG), cytoplasmic hypovirulent strains (CH), and virulent strains (V). Two types of cankers were initiated in …

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A Comparison Of The Growth And Asexual Reproduction By Cryphonectria Parasitica Isolates Infected With Hypoviruses Via Anastomosis And Transfection, Jenise M. Bauman Aug 2005

A Comparison Of The Growth And Asexual Reproduction By Cryphonectria Parasitica Isolates Infected With Hypoviruses Via Anastomosis And Transfection, Jenise M. Bauman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Transfection is an alternative laboratory method of hypovirus transmission that can be used to create hypovirulent strains. Results from a preliminary study at West Virginia University in 1998-99 indicated that recovery of hypovirulent isolates was similar between CHV1-infected anastomosed and transfected isolates. The objective of this research was to compare the two hypovirus acquisition methods in three experiments. The first study confirmed the performance of anastomosed and transfected isolates tested in a 1998-99 field study. In addition to the isolates previously evaluated, a third set of isolates containing CHV3-County Line was included. The size of cankers and the reisolation of …

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Refinement Of Numerical Models And Parametric Study Of Sofc Stack Performance, Andrew C. Burt Aug 2005

Refinement Of Numerical Models And Parametric Study Of Sofc Stack Performance, Andrew C. Burt

Graduate Theses, Dissertations, and Problem Reports (ETD)

The presence of multiple air and fuel channels per fuel cell and the need to combine many cells in series result in complex steady-state temperature distributions within Solid Oxide Fuel Cell (SOFC) stacks. Flow distribution in these channels, when non-uniform, has a significant effect on cell and stack performance. Large SOFC stacks are very difficult to model using full 3-D CFD codes because of the resource requirements needed to solve for the many scales involved. Studies have shown that implementations based on Reduced Order Methods (ROM), if calibrated appropriately, can provide simulations of stacks consisting of more than 20 cells …

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Development Of A Heavy Duty Diesel Vehicle Emissions Inventory Prediction Methodology, Prakash Gajendran Aug 2005

Development Of A Heavy Duty Diesel Vehicle Emissions Inventory Prediction Methodology, Prakash Gajendran

Graduate Theses, Dissertations, and Problem Reports (ETD)

Emissions from heavy-duty diesel vehicles are known to contribute a substantial fraction of the oxides of nitrogen (NOx), and particulate matter (PM) to the atmospheric inventory. Prediction of heavy-duty diesel vehicle emissions inventory is substantially less mature than the prediction of gasoline car emissions.;Heavy-duty truck emissions are affected by various parameters like vehicle weight/load, driving schedule used, and injection timing control strategies employed to operate the engine at more fuel-efficient (but higher NO x) mode.;Research has revealed a variety of options for inventory prediction, including the use of emissions factors based upon instantaneous engine power and instantaneous vehicle behavior. Effects …

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Critical Issues For Predicting Worker Exposure To Gaseous Contaminants In A Wind Tunnel, Jun Li Aug 2005

Critical Issues For Predicting Worker Exposure To Gaseous Contaminants In A Wind Tunnel, Jun Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study, three dimensional computational fluid dynamics (CFD) simulations are used to investigate the distribution and level of contaminant concentrations in the breathing zone of a worker when airborne contaminants are released within an arm's-length in front of the worker who has his back to the airflow. The main goals were to numerically evaluate the effect of different factors on the worker exposure and to recommend a turbulence model preferable for this type of simulation. These factors include the body shape, the heat flux from the body, the ventilation intensity, the free stream turbulence, and the unsteadiness. The comparison …

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Differences Among Standardized Test Scores Due To Factors Of Internet Access At Home And Family Affluence, Steve Macho Aug 2005

Differences Among Standardized Test Scores Due To Factors Of Internet Access At Home And Family Affluence, Steve Macho

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine differences among the standardized test scores of students due to factors of Internet access at home, household income, and the highest level of education attained by mother, father or guardian. If students with Internet access at home have a different academic standing, is it the result of the Internet connection or confounding factors of family affluence?;The San Miguel GEAR UP program at New Mexico Highlands University, located in Las Vegas, New Mexico had existent data on program participants for Internet access at home, household income, highest level of education in the household, …

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Rotation Compatibility Approach To Moment Redistribution For Design And Rating Of Steel I -Girders, Jennifer E. Righman Aug 2005

Rotation Compatibility Approach To Moment Redistribution For Design And Rating Of Steel I -Girders, Jennifer E. Righman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Moment redistribution refers to the design practice where the inherent ductility of continuous-span steel bridge structures is acknowledged and consideration for the redistribution of the large negative bending moments at interior supports to the less heavily stressed positive bending regions is provided. One of the key assumptions made in moment redistribution procedures is that members have sufficient ductility to sustain a given moment capacity throughout the level of rotation required for redistribution moments to develop. However, there is presently no explicit verification that this assumption is satisfied. Instead, it is assumed that sufficient ductility can be obtained by: (1) limiting …

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Performance Analysis Of Iris Based Recognition System At The Matching Score Level, Manasi V. Ketkar Aug 2005

Performance Analysis Of Iris Based Recognition System At The Matching Score Level, Manasi V. Ketkar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over the past three years, iris based personal identification has gained considerable attention both from research groups and government organizations. Public acceptance of this biometric grew substantially too. Modern cameras used for iris acquisition are less intrusive compared to earlier iris scanning devices and public awareness of system reliability is slowly developing. A typical iris system consists of four major subsystems: (i) image acquisition, (ii) preprocessing, (iii) encoding, (iv) decision making. Most current research is focused on redesigning preprocessing and encoding techniques for iris systems. However, a framework for comprehensive analysis of iris recognition systems or a study on how …

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Flow System Modeling With Applications To Fuel Cell Systems, Christian Edward Shaffer Aug 2005

Flow System Modeling With Applications To Fuel Cell Systems, Christian Edward Shaffer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fuel cell systems have garnered much attention recently as a possible source of clean, efficient energy. These systems are presently being designed in various arrangements to combine the use of fuel cells with other efficient power producing devices such as gas turbines, producing a system which is more efficient than either the fuel cell or gas turbine alone. The accurate modeling of these types of systems is an important contribution to the increasing development of such technologies. Of particular interest is the transient behavior of these systems, including the flow and thermal behavior of the air and fuel used. The …

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Vertical Stiffness Characterization Of A Geocomposite Drainage Layer For Pcc Highway Pavements, Joseph G. Sweet Aug 2005

Vertical Stiffness Characterization Of A Geocomposite Drainage Layer For Pcc Highway Pavements, Joseph G. Sweet

Graduate Theses, Dissertations, and Problem Reports (ETD)

One method for providing proper drainage for Portland Cement Concrete (PCC) highway pavement systems could be incorporating a geocomposite which creates a thin layer of voids through which water can flow. This research was done to develop a method for accounting for such a material during the thickness design of the PCC pavement. A theoretical method for predicting the results of field plate bearing tests of a soil system was adapted to include a geocomposite. Also, the vertical stiffness behavior of a particular geocomposite was characterized in the laboratory via uniaxial compression and cyclic fatigue tests. The validity of the …

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Post Retention With Mineral Trioxide Aggregate And Accelerated Portland Cement, Pamela P. Harrington Aug 2005

Post Retention With Mineral Trioxide Aggregate And Accelerated Portland Cement, Pamela P. Harrington

Graduate Theses, Dissertations, and Problem Reports (ETD)

Perforations occurring during post placement are problematic. Mineral trioxide aggregate (MTA) is slow to set. A trial demonstrated that CaCl2 accelerated the set of Portland cement. Forty single-rooted teeth were sectioned, treated with endodontic therapy and post prepared. The first group contained 20 teeth, evaluated at 72 hours. MTA, Portland cement with 10% CaCl2, 15% CaCl2 and zinc phosphate were used as post cements. The second group was evaluated at 28 days. The posts were cemented with either MTA or zinc phosphate. Instron mechanical testing was used to determine forces needed for post dislodgement. The 72 hour group showed statistically …

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Essays On The Publicness Of Education And The Effects Of School Choice On Student Achievement, Kerry A. King Aug 2005

Essays On The Publicness Of Education And The Effects Of School Choice On Student Achievement, Kerry A. King

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is a collection of papers that focus on the effects of school choice in the education market. The first chapter introduces the concept of school choice and discusses the arguments both for and against its implementation into public education. In addition, this chapter outlines the research agenda for this dissertation. Chapter 2 empirically measures the spillover benefits created by K-12 public education and finds that they are not Pareto-relevant at the margin. Given the results, this chapter also examines the role of school choice in the market for K-12 public education. Chapter 3 provides a brief history of …

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Palladium And Nickel Interactions With Stepped 6h-Silicon Carbide, Andrew A. Woodworth Aug 2005

Palladium And Nickel Interactions With Stepped 6h-Silicon Carbide, Andrew A. Woodworth

Graduate Theses, Dissertations, and Problem Reports (ETD)

Silicon carbide (SiC) has long been recognized as a semiconductor with potential for use in a number of demanding environments. Recent developments in the quality of bulk grown 6H-SiC (and other hexagonal poly-types) have increased interest in issues surrounding the stability of device structures that operate at temperatures in excess of 600°C. It has been observed that the performance of metal-semiconductor devices created on SiC tend to degrade when operating at these temperatures. This change in device performance has been linked to inter-diffusion and reaction at the metal-semiconductor interface. Most of these devices have been fabricated on SiC substrates with …

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Correlation Between Critical Thinking Skills And Decision Making Skills In Athletic Training And The Examination Of Critical Thinking Differences Across The Curriculum, Wanda S. Swiger Aug 2005

Correlation Between Critical Thinking Skills And Decision Making Skills In Athletic Training And The Examination Of Critical Thinking Differences Across The Curriculum, Wanda S. Swiger

Graduate Theses, Dissertations, and Problem Reports (ETD)

Athletic trainers evaluate an athlete's injury, make decisions regarding injury management, provide first aid and treatment, establish rehabilitation protocols, and evaluate the outcomes of their decisions. To practice effectively, they must think critically and make appropriate decisions. As educators make curriculum changes to improve decision making in athletic training, instructional methods to develop critical thinking continues to be proposed as a method to achieve this goal. This idea is based on the hypothesis that there is a DM-CT link, that athletic training students think critically, and that these instructional methods affect critical thinking. Additionally, issues continue to increase regarding the …

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Mesh Generation For Voxel -Based Objects, Hanzhou Zhang Aug 2005

Mesh Generation For Voxel -Based Objects, Hanzhou Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

A new physically-based approach to unstructured mesh generation via Monte-Carlo simulation is proposed. Geometrical objects to be meshed are represented by systems of interacting particles with a given interaction potential. A new way of distributing nodes in complex domains is proposed based on a concept of dynamic equilibrium ensemble, which represents a liquid state of matter. The algorithm is simple, numerically stable and produces uniform node distributions in domains of complex geometries and different dimensions. Well-shaped triangles or tetrahedra can be created by connecting a set of uniformly-spaced nodes. The proposed method has many advantages and potential applications.;The new method …

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Methods For Creating A Multi-Axis Polarizer For Visible Light Attenuation By Linear Translation, Peter L. Donatelli Aug 2005

Methods For Creating A Multi-Axis Polarizer For Visible Light Attenuation By Linear Translation, Peter L. Donatelli

Graduate Theses, Dissertations, and Problem Reports (ETD)

A few solutions exist that describe how a Linear Translation Multi-Axis (LTMA) polarizer can be made. It is the purpose here to describe some of these solutions and determine if these solutions are plausible. A positive result will be the creation of a LTMA polarizer in a continuous sheet.;As there are various ways to make a LTMA polarizer, there are also many materials used to make polarizers. Some of the types of polarizers that will be discussed consist of: a crystalline based dichroic polarizer, a molecular iodine polarizer, birefringent polarizers, metallic polarizers and light reactive dye polarizers.;What has resulted from …

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Prediction Of Coalbed Methane Reservoir Performance With Type Curves, Amol Bhaskar Bhavsar Aug 2005

Prediction Of Coalbed Methane Reservoir Performance With Type Curves, Amol Bhaskar Bhavsar

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study presents a set of production type curves for CBM reservoirs that would help the producers to predict the production from their CBM wells. As a consequence, the producers would be able to make better, more informed decisions regarding the CBM resources in the region. A reservoir model that incorporates the unique flow and storage characteristics of CBM reservoirs was employed in this study to develop the type curves. The type curves provide a reliable tool to predict the production performance of CBM reservoirs during dewatering phase. The application and issues concerning the production performance of CBM reservoirs are …

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Water Vapor Diffusion Through Glass Fiber Reinforced Polymer Nanocomposites, Mohit Bhardwaj Aug 2005

Water Vapor Diffusion Through Glass Fiber Reinforced Polymer Nanocomposites, Mohit Bhardwaj

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber reinforced plastics (FRPs) are used to make aircraft structures, highway bridges, automobile components, storage tanks, boat hulls, truck beds, and so on. When these FRPs are exposed to the atmosphere, environmental humidity can weaken the structural integrity and cause fiber delamination. The use of glass-fiber-reinforced nanocomposites made by addition of nanoclay, reduces the fiber damage and delamination because of its ability to enhance the barrier property of the matrix material. Clay not only acts as a barrier toward moisture diffusion, it also sequesters the moisture and protects the glass surface. During the course of this study the role of …

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Reservoir Characterization Using Intelligent Seismic Inversion, F. Emre Artun Aug 2005

Reservoir Characterization Using Intelligent Seismic Inversion, F. Emre Artun

Graduate Theses, Dissertations, and Problem Reports (ETD)

Integrating different types of data having different scales is the major challenge in reservoir characterization studies. Seismic data is among those different types of data, which is usually used by geoscientists for structural mapping of the subsurface and making interpretations of the reservoir's facies distribution. Yet, it has been a common aim of geoscientists to incorporate seismic data in high-resolution reservoir description through a process called seismic inversion.;In this study, an intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used …

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Field Measurement Of Ideal Saturation Flow Rate From The Highway Capacity Manual, Bruce M. Dunlap Aug 2005

Field Measurement Of Ideal Saturation Flow Rate From The Highway Capacity Manual, Bruce M. Dunlap

Graduate Theses, Dissertations, and Problem Reports (ETD)

In all signalized intersection analyses performed with Highway Capacity Manual (HCM), the Pennsylvania Department of Transportation (PENNDOT) District 12-0 uses an ideal saturation flow rate of 1800 pcphgpl, which is less than the default value of 1900 pcphgpl provided by HCM. This is to account for the less aggressive characteristics of the local drivers. The purpose of this study is to field measure a sample of saturation flow rates, from which ideal saturation flow rates can be computed, in District 12-0 to determine the appropriateness of the lower ideal saturation flow rate. This study will scientifically test this hypothesis, along …

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Fabrication Of Resonant Optical Waveguide Biosensors Using Electron Gun Depositions, Timothy Allen Cornell Aug 2005

Fabrication Of Resonant Optical Waveguide Biosensors Using Electron Gun Depositions, Timothy Allen Cornell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Biosensors are used to connect the chemical and physical worlds through the use of a transducer, allowing for quick detection of numerous biological agents. A new biosensor being developed, the resonant optical waveguide biosensor, uses power transfer between two optical waveguides to detect the presence of an antigen. The condition for power transfer is extremely sensitive to changes in index of refraction and allows the biosensor to have a high sensitivity to the antigen presence. Given the high sensitivity of the device, a high degree of accuracy in index of refraction and thickness is required from the fabrication process.;Fabrication of …

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