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Design Of 2.4 Ghz And 5ghz Rfic Front-End Components In Cmos And Silicon-Germanium Hbt Technologies., Rahul Madhav Kodkani
Design Of 2.4 Ghz And 5ghz Rfic Front-End Components In Cmos And Silicon-Germanium Hbt Technologies., Rahul Madhav Kodkani
Graduate Theses, Dissertations, and Problem Reports (ETD)
In the last few years, multiple wireless networking standards have evolved. Standards such has Bluetooth and IEEE 802.11 have emerged to provide high-speed wireless interconnectivity. Along with advances in the wireless technology, there has also been a significant development in Silicon Radio Frequency Integration. New technologies such as the SiGe BiCMOS have been developed which have exhibited superior RF performance. The CMOS technology, which has proven itself in the entrenched digital arena, has been questioned for its performance at radio frequencies. In the recent past, various enhancements have been made to the standard digital CMOS process for use in RF …
A Comparative Study Of Shrinkage And Cracking Of High-Performance Concrete Mixtures For Bridge Decks., Jennifer Lynne Morris
A Comparative Study Of Shrinkage And Cracking Of High-Performance Concrete Mixtures For Bridge Decks., Jennifer Lynne Morris
Graduate Theses, Dissertations, and Problem Reports (ETD)
To alleviate the deterioration of concrete structures, High-Performance Concrete (HPC) is extensively used, particularly for bridge decks, due to its favorable durability characteristics. However, there is a problem with the high cracking tendency of HPC due to its high early shrinkage, low water-cementitious ratio, brittleness and low creep. Thus, the HPC advantages of high compressive strength and low permeability are somewhat offset by cracking problems, which reduce the service life of bridge decks. To improve this problem, the goal of this study is to modify conventional HPC mixtures with admixtures or modifiers to obtain low-cracking or no-cracking formulations using West …
Attachment, Gender, And Personality: An Exploration Into The Affective Components Of Adult Attachment In A Non-Clinical Sample., Daniel Joseph Fox
Attachment, Gender, And Personality: An Exploration Into The Affective Components Of Adult Attachment In A Non-Clinical Sample., Daniel Joseph Fox
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study used a total of 243 undergraduate students to examine differences in attachment style and personality. The Hazan and Shaver (1987) attachment measure and the Relationship Questionnaire (Bartholomew and Horowitz, 1991) were used to discern attachment type. The Multidimensional Personality Questionnaire-155 (Patrick, Curtin, & Tellegan, 2000) and the Tennessee Self-Concept Scale, Second Edition (Fritts & Warren, 1996) were used to identify global personality variables. Findings revealed that the two attachment measures are highly related, and positive correlations were found between the global personality constructs of Positive Emotionality, Constraint, and Total Self-concept. The constructs of Negative Emotionality and Conflict were …
Effects Of Vehicle Weight And Model Year On Vehicle Contribution To Atmospheric Pollutant Inventories., Timothy S. Hall
Effects Of Vehicle Weight And Model Year On Vehicle Contribution To Atmospheric Pollutant Inventories., Timothy S. Hall
Graduate Theses, Dissertations, and Problem Reports (ETD)
The objective of this study was to determine the effects of vehicle weight and model year on vehicle contribution to atmospheric pollutant inventories. The weight class of the vehicle was found to have the greatest impact on vehicle emissions with NOx increasing 285% while PM increased 269% when going from a 12,000 lbs GVWR vehicle to a 52,000 GVWR vehicle with engines certified to the same emissions standards. The vehicle age had a significant impact on emissions production with NOx and PM both increasing 148% and 183% respectively going from a 1985 model year vehicle to a year 2000 model …
Changes In Water Quality In Deckers Creek From 1974 To 2000, Jason Allen Stewart
Changes In Water Quality In Deckers Creek From 1974 To 2000, Jason Allen Stewart
Graduate Theses, Dissertations, and Problem Reports (ETD)
The Deckers Creek drainage basin covers approximately 16,600 hectares (62.9 square miles) in Monongalia and Preston Counties of West Virginia. Throughout the twentieth century, this watershed has received high levels of pollution in several forms. A 1974 study examined the water chemistry in Deckers Creek over a six-month period at 29 sample points. Water samples from the same sites were collected and analyzed monthly from March 1999 through October 2000 for acidity, alkalinity, total iron, aluminum, manganese, and other metals, as well as for fecal coliform and fecal streptococcus concentrations. Most of the tributaries sampled in 1999--2000 showed reduced metal …
Large -Eddy Simulation Of A Three-Dimensional Compressible Tornado Vortex, Jianjun Xia
Large -Eddy Simulation Of A Three-Dimensional Compressible Tornado Vortex, Jianjun Xia
Graduate Theses, Dissertations, and Problem Reports (ETD)
Large-Eddy simulation (LES) has become a very useful tool for investigating tornadoes, one of the more spectacular and destructive phenomena of nature. A new three-dimensional, unsteady, compressible model is generated to determine how significant the differences between compressible and incompressible LES simulations may be in some extremely violent tornadoes. In particular, this study seeks to determine how high the Mach number within the tornado may become before significant changes occur due to compressibility, and what the major effects of these changes may be expected to be.;After developing and verifying the compressible LES model, three different patterns of tornadic corner flows …
Investigation Of Diesel Soot-Mediated Oils And Additive Package On Wear, Santhosh Kumar Balla
Investigation Of Diesel Soot-Mediated Oils And Additive Package On Wear, Santhosh Kumar Balla
Graduate Theses, Dissertations, and Problem Reports (ETD)
In the current study, a statistically designed experiment was developed to study the effects of soot contaminated engine oil on wear. The variables that were considered were the Base stock (Group1, Group2), Dispersant level and ZDP level. The above three variables were formulated at two levels: Low (-1), and High (1), which resulted in 23 matrix (8 oil blends). Soot was also one of the variables and was tested at three levels: Low (-1), Medium (0) and High (1).;A three-body-wear machine was employed to simulate and estimate the extent of wear, as it is very difficult to test each oil …
Improved Velocity Data In Circular Jets Using An Avalanche Photodiode-Based 2-Component Point Doppler Velocimeter, Thomas Trent Scarberry
Improved Velocity Data In Circular Jets Using An Avalanche Photodiode-Based 2-Component Point Doppler Velocimeter, Thomas Trent Scarberry
Graduate Theses, Dissertations, and Problem Reports (ETD)
An existing Point Doppler Velocimeter (pDv) has been modified in an effort to improve the RMS velocity results. Improvements have been made by reducing the probe volume size by focusing the incident laser beam, thereby reducing the effects of spatial averaging on the mean and RMS velocity measurements.;In particular, the PIN photodetectors used previously, were tested using the reduced probe volume, and were then replaced by high-gain, high signal-to-noise ratio large area avalanche photodetectors (APD's).;Comparisons have been made between the data acquired and hot wire data obtained on the same jet flow, as well as data obtained in previous pDv …
Effects Of Baffles On Damping Lateral Fluid Sloshing Oscillations In Tanker Trucks, Rohit Kumar Tanugula
Effects Of Baffles On Damping Lateral Fluid Sloshing Oscillations In Tanker Trucks, Rohit Kumar Tanugula
Graduate Theses, Dissertations, and Problem Reports (ETD)
Partially filled heavy-duty tanker trucks maneuvering constant radius turns or lane change maneuvers have lower rollover threshold than other vehicles because of the high center of gravity and dynamic sloshing of the liquid payload. Payloads are often toxic and hence, rollover accidents can be catastrophic. Therefore, attempts to increase the threshold velocity and predicting its value under various on-road maneuvers are of paramount importance.;This research was aimed at studying the effects of baffles on reducing the lateral sloshing and thereby, improving the stability of heavy-duty trucks. Various configurations (horizontal, vertical, horizontal and vertical, and diagonal) of baffles were considered for …
Study Of West Virginia Wood Industry Roundwood Consumption In 1999, O'Dell Emanuel Tucker
Study Of West Virginia Wood Industry Roundwood Consumption In 1999, O'Dell Emanuel Tucker
Graduate Theses, Dissertations, and Problem Reports (ETD)
Use of wood composite products has increased over the last decade in the market for construction material. Softwood species and soft hardwood species are the preferred forest resources for manufacturing these products. Reduction in available softwood forest resources from the Western states has forced a shift to use of more soft hardwood species in the Northeast. What impact this shift may have on the forest resources in the Northeast is not known.;The objective of this study was to canvass primary wood manufacturers in and around the forest of West Virginia and determine how roundwood consumption has changed since the shift …
Large -Eddy Simulation Of Ship Wakes, Shaoping Shi
Large -Eddy Simulation Of Ship Wakes, Shaoping Shi
Graduate Theses, Dissertations, and Problem Reports (ETD)
The objective of the present study is to improve our understanding of turbulent wake flows. Large-Eddy Simulation (LES) technique is applied for this purpose. A readily available code was used with necessary modifications. Three dimensional incompressible Navier-Stokes equations are solved in non-orthogonal curvilinear coordinates. Finite-volume approach is implemented on a non-staggered grid. The core of the numerical scheme is a fractional step method. The overall accuracy of the method is second order in both space and time.;The LES approach has been validated for four cases: channel flow, flow past a square body, a shear layer flow, and open channel flow. …
Toward High-Definition Reservoir Characterization, Gheorghe Luca
Toward High-Definition Reservoir Characterization, Gheorghe Luca
Graduate Theses, Dissertations, and Problem Reports (ETD)
A new methodology for high resolution reservoir characterization is proposed. It combined the advantages of the surface seismic (low resolution, large coverage) and crosswell seismic (improved resolution, small coverage).;The process involves deconvolution of a low resolution signal (surface seismic traces) into a high resolution crosswell seismic trace. The problem has multiple solutions and an analytical solution is hard or difficult to be developed.;This project proved that it is possible to predict high-resolution crosswell seismic traces using low-definition surface seismic traces. The statistical comparison between the real and the synthetic crosswell seismic traces gives confidence that future work in this area …
Moisture Diffusion Through Vinyl Ester/Clay Nanocomposites, Apoorva Paresh Shah
Moisture Diffusion Through Vinyl Ester/Clay Nanocomposites, Apoorva Paresh Shah
Graduate Theses, Dissertations, and Problem Reports (ETD)
Moisture diffusion was studied through vinyl ester samples containing up to 5 wt% montmorillonite clay; two different kinds of clay surface treatments were employed to make the clay compatible with the vinyl ester resin. These nanocomposites were characterized using differential scanning calorimetry (DSC), mechanical property measurements, x-ray diffraction (XRD) and transmission electron microscopy (TEM). TEM pictures showed that the clay platelets were either exfoliated or intercalated, and the two different surface treatments resulted in different dispersion characteristics. All the samples were post cured, and the diffusivity of moisture was measured by soaking the samples in water at 25°C and noting …
Optical Gradation For Crushed Limestone Aggregates, Ken Cheng
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 …
Habitat Utilization And Movement Patterns Of Subadult Largemouth Bass (Micropterus Salmoides) In The Ohio River, Elizabeth Marie Hoffman
Habitat Utilization And Movement Patterns Of Subadult Largemouth Bass (Micropterus Salmoides) In The Ohio River, Elizabeth Marie Hoffman
Graduate Theses, Dissertations, and Problem Reports (ETD)
Ohio River electrofishing surveys identified embayments as preferred macrohabitat of subadult largemouth bass. Catch rates within macrohabitats were low ranging from 0.00--2.73 subadult bass/hour. Embayment electrofishing CPUE was higher than tributary or main channel except in spring, when tributary CPUE was highest.;Core use areas were calculated from biotelemetry data and ranged from 88--59,400 m2, representing 0.02--89.00% of available study location macrohabitat. Subadult bass movement was limited to nursery embayments or tributaries with infrequent movement to nearby main channel areas. Bass preferred a mixed microhabitat consisting of a combination of vegetation and woody debris. This mixed microhabitat was less common in …
Lda And Cta In-Cylinder Measurements Of Intake-Generated Turbulence For Steady Flow Around A Centrally Located Valve, Gearle Ray Bailey Jr.
Lda And Cta In-Cylinder Measurements Of Intake-Generated Turbulence For Steady Flow Around A Centrally Located Valve, Gearle Ray Bailey Jr.
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was to measure the axial and swirl velocities for steady flow in a cylinder past an intake valve, in order to study the effects of swirl and valve lift on turbulence generation. A simple geometry was used for an initial look at the flow past a valve.;A cylinder with a centrally located valve was used as the test bed. The valve was tested at lifts of 4 and 9 mm Two intake geometries were tested: a straight intake port and a swirl intake port. A single sensor Constant Temperature Anemometry (CTA) and a one-component Laser …
Fuzzy Logic Cost Estimation Method For High Production Volume Components, Shirley Jean Copen
Fuzzy Logic Cost Estimation Method For High Production Volume Components, Shirley Jean Copen
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this research is to develop fuzzy logic cost models that estimate the cost of a component based on the component's geometric shape, size, material and manufacturing process. The research is focused on components made from high production quantity processes i.e. stamping, injection molding, rolling and extrusion. However, the method may also be used for other types of manufacturing processes. The method is useful to both engineers and cost estimators whenever an estimated cost is desired. Engineers and cost estimators may use the method to obtain the cost of components or products of similar design without a detailed …
Study Of The Rheological Properties Of Nomex Fibrids, Long Han
Study Of The Rheological Properties Of Nomex Fibrids, Long Han
Graduate Theses, Dissertations, and Problem Reports (ETD)
Paints and caulks typically contain (spherical) fumed silica particulates as viscosity enhancers. A similar viscosity enhancement can be achieved by using aramid fibrids. Aramid fibrids are believed to form microstructures in suspensions because of the "space-filling" nature of their shapes and thus provide a convenient means of introducing desired rheological behavior for various commercial applications.;The flow responses of aramid fibrids dispersed in mixtures of corn syrup and water were determined in dynamic shear, steady shear, low shear capillary, and extensional stretching flows. Yield stress, strong shear thinning, thixotropy, and strong dispersion effects were observed, and these are consistent with observed …
Simulated Annealing Heuristics For The Dynamic Facility Layout Problem, Saravanan Kuppusamy
Simulated Annealing Heuristics For The Dynamic Facility Layout Problem, Saravanan Kuppusamy
Graduate Theses, Dissertations, and Problem Reports (ETD)
Today's consumer market demands that manufacturers must be competitive. This requires the efficient operation of manufacturing plants and their ability to quickly respond to changes in product mix and demand. Studies show that material handling cost makes up between 20 and 50 percent of the total operating cost. Therefore, this thesis considers the problem of arranging and rearranging (when there are changes in product mix and demand) manufacturing facilities such that material handling and rearrangement costs are minimized. This problem is called the dynamic facility layout problem. In this thesis, three simulated annealing heuristics are presented for the dynamic facility …
New Catalysts For Syngas Production From Carbon Dioxide And Methane, Mahesh Venkataraman Iyer
New Catalysts For Syngas Production From Carbon Dioxide And Methane, Mahesh Venkataraman Iyer
Graduate Theses, Dissertations, and Problem Reports (ETD)
The performance of cobalt tungsten carbide material was investigated for CH4/CO2 reforming. The catalyst was found to convert to a very stable, very active, form when heated in CH4/CO 2 at 850°C and 5 atm. Even after 90 hours on stream, CH4 and CO2 rates of 1.3 and 1.25 mmol/min/g respectively are obtained, with CO yields of 76% and H2/CO ratio close to unity. XRD patterns suggest a phase transformation to WC+Co+C. SEM images suggest formation of encapsulated carbon and whisker carbon.;The kinetics of CH4/CO2 reforming was studied under differential conditions over 500--600°C. The observed rates seem to follow a …
Development Of Environmental Health And Safety Database For Small Communities, Ragava S. Nadig
Development Of Environmental Health And Safety Database For Small Communities, Ragava S. Nadig
Graduate Theses, Dissertations, and Problem Reports (ETD)
The National Environmental Services Center (NESC) is a group of programs, national in scope, that provide a variety of environmental services directly to small community officials, engineers, technicians, regulatory officials, and private citizens.;The primary mission of each of the NESC programs is to protect public health and the environment of America's small and rural communities-those communities of less than 10,000 people. The NESC programs provide information, technical assistance, and training to help small communities deal with their wastewater, drinking water, and solid waste treatment issues.;Thousands of informational materials pass through the organization each year. This material ranges from manufacturing product …
Detection Of Subsurface Anomalies In Fiber-Reinforced Polymer (Frp) Wrapped Timber Bridge Components Using Infrared Thermography, William Edward Steele Iii
Detection Of Subsurface Anomalies In Fiber-Reinforced Polymer (Frp) Wrapped Timber Bridge Components Using Infrared Thermography, William Edward Steele Iii
Graduate Theses, Dissertations, and Problem Reports (ETD)
This thesis presents the results of an experimental study on the use of Infrared Thermography technique for detection of subsurface anomalies in fiber reinforced polymer (FRP) wrapped timber bridge components. An extensive literature review on the application of various nondestructive evaluation techniques to composite structures has also been presented.;Simulated subsurface delaminations were constructed in the laboratory in timber piles wrapped with FRP composite fabric. The delaminations varied in size, thickness, and severity. These delaminations were placed between the 1/8&inches; thick FRP wrap and timber surface. The thermal images from the delaminated specimens were compared with thermal images from undamaged specimens …
Exploring Object-Oriented Gis For Watershed Resource Management, Nalishebo Nally Kaunda
Exploring Object-Oriented Gis For Watershed Resource Management, Nalishebo Nally Kaunda
Graduate Theses, Dissertations, and Problem Reports (ETD)
The adoption of object-oriented programming for spatial technological advancement is an emerging trend in GIS. This research seeks to explore Object-Oriented GIS (OOGIS) and its potential application in watershed resource management. OOGIS provides a more intuitive and realistic abstraction of real world features as intelligent objects. The ability to embed behavior, geometry, and attribution with the objects provides considerable advantages in the processing and analysis of geospatial data. The main objective of this research was to design a prototype OOGIS for watershed resource management using the object relational Arclnfo 8.1 Geodatabase. The study builds on the OOGIS concepts of inheritance, …
Multifractal Analysis Of Memory Usage Patterns, Jonathan Browning Crowell
Multifractal Analysis Of Memory Usage Patterns, Jonathan Browning Crowell
Graduate Theses, Dissertations, and Problem Reports (ETD)
The discovery of fractal phenomenon in computer-related areas such as network traffic flow leads to the hypothesis that many computer resources display fractal characteristics. The goal of this study is to apply fractal analysis to computer memory usage patterns. We devise methods for calculating the Holder exponent of a time series and calculating the fractal dimension of a plot of a time series. These methods are then applied to memory-related data collected from a Unix server. We find that our methods for calculating the Holder exponent of a time series yield results that are independently confirmed through calculation of the …
Development Of Instrumentation For The Investigation Of Surface Regeneration For Candle Filters, Sean Patrick Gregory
Development Of Instrumentation For The Investigation Of Surface Regeneration For Candle Filters, Sean Patrick Gregory
Graduate Theses, Dissertations, and Problem Reports (ETD)
Two methods of improving efficiency of coal based power generation are integrated gasification combined-cycle (IGCC) and pressurized fluidized-bed combustion (PFBC). Both of these options require high-temperature gas stream particle cleanup for optimum efficiency. Candle filters in a pressurized vessel have received the greatest amount of attention in dealing with this topic, but problems still persist and there does not seem to be clear-cut answer to the problem. This research is an investigation of the candle filter cleaning process, a process known as surface regeneration.;The objective of this research program has been to develop the instrumentation necessary to investigate the surface …
Electrical Characterization Of Thin Film Nanostructure Templates, Christopher James Garman
Electrical Characterization Of Thin Film Nanostructure Templates, Christopher James Garman
Graduate Theses, Dissertations, and Problem Reports (ETD)
An improved apparatus for anodizing aluminum films on Si substrates is presented. In addition, an explanation is given for adapting the system to SiC and glass substrates. The system presented is optimized for throughput and safety to focus on volume production. MOS capacitors created with the system are analyzed with capacitance-voltage measurement techniques to provide insight into device operation. Ni is deposited into porous alumina templates to create Ni nanostructures.
Kinematic Synthesis Of A Well Service Machine, Prashanth Kaparthi
Kinematic Synthesis Of A Well Service Machine, Prashanth Kaparthi
Graduate Theses, Dissertations, and Problem Reports (ETD)
Blowout preventers are used in the oil well industry to prevent accidental oil fires, and guide valves are assembled atop the preventers. The current solution is to use cranes, as this is time-consuming and expensive, a solution using an appropriate four-bar mechanism for this purpose was contemplated, using Burmester theory and the four-position synthesis method.;The angles and distance of the four positions were calculated and the data obtained was specified as input for the synthesis of the four-bar mechanism using four-position synthesis programmed in MATLAB(TM). The moving pivots (k) and the ground pivots (m) were obtained from the program and …
Simulation Of Heavy-Duty Hybrid Electric Vehicles, Anjali Devi Nennelli
Simulation Of Heavy-Duty Hybrid Electric Vehicles, Anjali Devi Nennelli
Graduate Theses, Dissertations, and Problem Reports (ETD)
Microsoft Excel and ADvanced VehIcle SimulatOR (ADVISOR) were used to simulate the driving conditions of heavy-duty hybrid electric vehicles over various driving cycles in an attempt to optimize their design and control. The fuel economy data thus obtained were compared with those of the in-use heavy-duty hybrid electric vehicles. For this the drive cycles are modified to represent realistic expectations of the dynamic performance of vehicles. The cycles used are "Central Business District" cycle (CBD), "Urban Dynamometer Driving Schedule" cycle (UDDS), "Manhattan" cycle and "City Suburban Heavy Vehicle Cycle" (CSHVC). The vehicle considered for simulations was a transit bus, which …
Fabrication Of Thin Film Nanoscale Alumina Templates, Paul B. Sines
Fabrication Of Thin Film Nanoscale Alumina Templates, Paul B. Sines
Graduate Theses, Dissertations, and Problem Reports (ETD)
Semiconductor nanostructures have superior electronic and optical properties that are expected to play an important role in 21st century electronic and photonic devices. Recognizing this potential, semiconductor nanostructures have been the focus of research over the past 25 years, and many ultra-high performance devices have been demonstrated. While the potential of this class of devices is clear, their commercial applications have been limited by the lack of a fabrication process suited to economical volume production. The initial method of nanostructure fabrication using electron beam lithography and reactive ion etching is not considered practical due to its high cost and low …
Characterization Of Stresses Induced In Doweled Joints Due To Thermal And Impact Loads, Shiva Srinivasan
Characterization Of Stresses Induced In Doweled Joints Due To Thermal And Impact Loads, Shiva Srinivasan
Graduate Theses, Dissertations, and Problem Reports (ETD)
A review of literature on dowel jointed concrete pavement response reveals that the effect of uniform temperature changes was neglected based on the assumption that concrete slabs can contract freely. The triaxial state of stresses that develop at the dowel concrete interfaces due to the application of mechanical and thermal loads has not been previously characterized. In this study a detailed Three-Dimensional Finite Element (3D FE) model was used to investigate the state of contact stresses, mid slab stresses, and load transfer efficiency that develop in dowel jointed concrete pavements under the influence of combined impact and thermal loads. The …