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Articles 31 - 60 of 261
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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
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 …
Transfer Of Heart Rate Feedback Training To Reduce Heart Rate Response To Laboratory Tasks, Jeffrey Louis Goodie
Transfer Of Heart Rate Feedback Training To Reduce Heart Rate Response To Laboratory Tasks, Jeffrey Louis Goodie
Graduate Theses, Dissertations, and Problem Reports
Researchers have demonstrated that individuals can successfully reduce their heart rate (HR) response to a stressor when provided with heart rate feedback. However, it is unclear whether individuals can transfer HR reduction skills to stressors not used during HR feedback training. The present study used a multiple baseline, single subject design to examine the transfer of HR feedback training among six individuals. Participants were provided with HR feedback training during the presentation of a videogame, a mental arithmetic challenge, and a hand grip task until the participants reduced their HR to within 4 bpm of their resting HR or until …
Electrochemical Fabrication Of Semiconductor Nanostructure Arrays For Photonic Applications, Stephen Patrick Mcginnis
Electrochemical Fabrication Of Semiconductor Nanostructure Arrays For Photonic Applications, Stephen Patrick Mcginnis
Graduate Theses, Dissertations, and Problem Reports
Theoretical and experimental investigations of the properties of semiconductor nanostructures have been an active area of research due to the enhanced performance that is observed when electrons and holes are spatially confined in one, two or three dimensions. However, the development of viable photonic devices using this phenomenon requires the development of appropriate fabrication techniques that can provide control over nanostructure size, material composition, and periodicity for structures with dimensions less than 20 nm. To address these challenges, a nanostructure synthesis technique has been developed that is based on the self-organization of nanometer scale pores during the anodization of aluminum …
Parent Distress, Parent Behavior, And Infant Distress During Pediatric Immunizations, Rebecca Suzanne Bernard
Parent Distress, Parent Behavior, And Infant Distress During Pediatric Immunizations, Rebecca Suzanne Bernard
Graduate Theses, Dissertations, and Problem Reports
Infant procedural distress historically has been ignored, and the importance of reducing infant distress only recently has been addressed. To understand and manage infant procedural distress, it is essential to examine the correlates and potential predictors of this distress. The purpose of this study was to examine the effects of parent distress on infant procedural distress, the effects of parent behavior on infant distress, and the combined impact of parent distress and behavior on infant distress for 37 parent-infant dyads. Results demonstrated that infant measures were not intercorrelated, only parent self-report measures were intercorrelated, and several measures of parent distress …
Order Effects Of Fear And Pain Induction, Kevin Erik Vowles
Order Effects Of Fear And Pain Induction, Kevin Erik Vowles
Graduate Theses, Dissertations, and Problem Reports
Although pain responding and emotional states such as fear are highly correlated and appear to interact, the causal relations between these variables have yet to be fully defined. This study sought to further illuminate these relations by investigating how exposure to one of these states (i.e., pain or fear) affects responding to the other. The order in which participants experienced fearful or painful stimuli was manipulated, as well as fear level (i.e., "low" & "high"). Measures of behavioral escape, heart rate, and verbal reports were obtained throughout four experimental trials, as well as rankings of aversiveness for all stimuli encountered. …
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
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
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
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 …
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
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.
Multifractal Analysis Of Memory Usage Patterns, Jonathan Browning Crowell
Multifractal Analysis Of Memory Usage Patterns, Jonathan Browning Crowell
Graduate Theses, Dissertations, and Problem Reports
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 …
Kinematic Synthesis Of A Well Service Machine, Prashanth Kaparthi
Kinematic Synthesis Of A Well Service Machine, Prashanth Kaparthi
Graduate Theses, Dissertations, and Problem Reports
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 …
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
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 …
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
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 …
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
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 …
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
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 …
Factors Affecting The Accumulation Of Pentosidine In The Skin Of Wild Birds, Richard Clair Chaney Jr.
Factors Affecting The Accumulation Of Pentosidine In The Skin Of Wild Birds, Richard Clair Chaney Jr.
Graduate Theses, Dissertations, and Problem Reports
Birds have few reliable indicators of aging. Pentosidine (Ps), a biomarker of aging, is a product of non-enzymatic glycation, which accumulates in the tissues of an animal over its lifespan. The intent of this study was to determine if comparable change in Ps concentrations could be established in the skin of wild birds of known ages. Skin samples were obtained from the breast of 44 birds of various species. Foot webbing samples were obtained from 24 California Gulls. Collagen was measured by a hydroxyproline spectrophotometric method and Ps was quantified using reverse phase HPLC. Ps concentration in the skin and …
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
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 …
Novel Synthesis Of 3,4-Fused Indoles, Jeremiah Wallace Hubbard
Novel Synthesis Of 3,4-Fused Indoles, Jeremiah Wallace Hubbard
Graduate Theses, Dissertations, and Problem Reports
The goal of this project was to synthesize 3,4-fused indoles having a variety of ring sizes and a variety of functional groups. This has been accomplished by the development of a novel palladium-catalyzed route to 3,4-fused indoles. The key steps are two palladium-catalyzed reactions, an intramolecular Heck reaction followed by a reductive N-heteroannulation. Using this route, a number of 3,4-fused indoles were prepared in acceptable yields.
Influence Of The West Virginia Dome On Paleocurrent Patterns In The Upper Devonian-Lower Mississippian Price Formation In The Central Appalachians, Sheldon James Murphy
Influence Of The West Virginia Dome On Paleocurrent Patterns In The Upper Devonian-Lower Mississippian Price Formation In The Central Appalachians, Sheldon James Murphy
Graduate Theses, Dissertations, and Problem Reports
Upper Devonian-Lower Mississippian sedimentation was influenced by a positive area known as the West Virginia Dome located in the Central Appalachians of West Virginia. Paleocurrent data collected from the Price Formation demonstrates the significance of the dome on paleoflow patterns. Exposures in West Virginia are located along the Allegheny Front and include the lowermost marine Oswayo Member, Riddlesburg Shale Member, unnamed Upper Member and the uppermost non-marine Rockwell Member. These units overlie the Devonian Hampshire Formation or Greenland Gap Formation and underlie the Mississippian Greenbrier Limestone or Maccrady Formation. At the center of the dome the Price Formation is absent …
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
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 …
Characterization And Quality Of Soils Developing On A Mountaintop Removal Coal Mine, Kevin Alfred Thomas
Characterization And Quality Of Soils Developing On A Mountaintop Removal Coal Mine, Kevin Alfred Thomas
Graduate Theses, Dissertations, and Problem Reports
Mountaintop surface mining for coal has been practiced in West Virginia for over three decades, but its environmental impacts have become increasingly scrutinized in recent years. Therefore, this study evaluated soil development on different aged mined lands. Four different ages (2, 7, 11, and 23 years) of minesoils and two different slope classes, nearly level to gently sloping and steep to very steep, along with three contiguous native soils on a reclaimed mountaintop removal mine in Logan County, West Virginia were described and sampled. Standard analyses of physical and chemical properties were conducted in order to classify these soils. Some …
Mechanisms Of Retroviral Replication, Timur O. Kabdulov
Mechanisms Of Retroviral Replication, Timur O. Kabdulov
Graduate Theses, Dissertations, and Problem Reports
Specific encapsidation of viral RNA is an essential step of retroviral replication cycle. Extensive biochemical and genetic analyses suggest that majority of retroviruses employ similar mechanisms for specific RNA packaging. Better understanding of mechanisms of this process may help to develop new anti-retroviral drugs against such serious pathogens as human immunodeficiency virus types 1 and 2.;This study concerns with specific packaging of RNA by two simple retroviruses, murine leukemia virus (MLV) and spleen necrosis virus (SNV). SNV proteins can package RNA of both SNV and MLV with similar efficiency. In contrast, MLV proteins cannot package SNV RNA. NC domain was …
Raptor Abundance And Diversity And Red-Shouldered Hawk ( Buteo Lineatus) Habitat Characteristics On Reclaimed Mountaintop Mines In Southern West Virginia, Melissa J. Balcerzak
Raptor Abundance And Diversity And Red-Shouldered Hawk ( Buteo Lineatus) Habitat Characteristics On Reclaimed Mountaintop Mines In Southern West Virginia, Melissa J. Balcerzak
Graduate Theses, Dissertations, and Problem Reports
Raptor abundance and diversity were compared between 4 treatments (grassland, shrub/pole, fragmented forest, and intact forest) over 3 seasons (migration, summer, and winter) on 3 mountaintop/valley fill mines in southern West Virginia. Habitat characteristics of Red-shouldered Hawks (Buteo lineatus) were examined at landscape and microhabitat scales. Forty-eight points were surveyed monthly (Feb. 2000--Jan. 2001) using broadcast calls. I quantified microhabitat characteristics within an 11.3 m radius plot and landscape characteristics within 1000 and 564 m buffer zones at each point. Abundance was highest in grasslands; richness did not differ among treatments. Overall, I detected a shift from a forest to …
Optical Gradation For Crushed Limestone Aggregates, Ken Cheng
Optical Gradation For Crushed Limestone Aggregates, Ken Cheng
Graduate Theses, Dissertations, and Problem Reports
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 …
Rates Of Adoption In A University Course Management System, David Russell Feeney
Rates Of Adoption In A University Course Management System, David Russell Feeney
Graduate Theses, Dissertations, and Problem Reports
This research focuses on diffusion of an education innovation in a large, traditional University. In March 1999, the Blackboard digital course management system was installed for enterprise-wide availability at Temple University, the 39th largest university in the United States. The web-enabled database of Temple Blackboard logs the adoption date, course ID, and course title for every Blackboard course, unobtrusively, twenty-four hours a day. Temple Blackboard serves as 4 digital approximation of the cumulative recorder pioneered by B. F. Skinner, recording more than 2800 course adoptions across 30 months, in real time. Temple Blackboard course records provide unprecedented quantity and quality …
Parent-Infant Interactions During Acute Painful Procedures, Catherine Bradford Mcclellan
Parent-Infant Interactions During Acute Painful Procedures, Catherine Bradford Mcclellan
Graduate Theses, Dissertations, and Problem Reports
Despite the current recognition of infant procedural pain and distress, there is a dearth of research, both in the assessment and treatment literature, of infant procedural distress. This study examined how specific parent behaviors relate to infant procedural distress and whether this relation is mediated by birth order. Results indicated that females were rated as more distressed than were males, and that birth order did not prove to be a distinguishing factor in infant distress. Finally, while some behaviors appear to have a similar influence on both preschoolers' and infants' behaviors, parents' behavior during infants' distressing procedures were found to …
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
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, …
Reasons For Living Across The Lifespan, Lesley P. Koven
Reasons For Living Across The Lifespan, Lesley P. Koven
Graduate Theses, Dissertations, and Problem Reports
This study examined gender and age-related differences in reasons for living, using a sample of 50 young adults (M = 20.2), 53 middle-aged adults (M = 49.3), and 55 older adults ( M = 78.5). Participants completed a combined version of the Reasons for Living Inventory, the Reasons for Living Inventory for Younger Adults, and the Reasons for Living Inventory for Older Adults. Although no gender differences emerged in reasons for living, younger adults placed more importance on fear of social disapproval, moral objections, survival and coping skills, peer acceptance, survival and coping beliefs, fear of suicide, and future optimism …
Analytical And Experimental Study Of Frp Honeycomb Sandwich Panels With Sinusoidal Core, Justin Mark Robinson
Analytical And Experimental Study Of Frp Honeycomb Sandwich Panels With Sinusoidal Core, Justin Mark Robinson
Graduate Theses, Dissertations, and Problem Reports
Fiber reinforced plastic (FRP) composite materials and structures have been increasingly used in highway bridge applications. Recent applications have demonstrated that FRP honeycomb sandwich panels with sinusoidal core can be effectively and economically used for highway bridge deck systems. In this study, analytical and experimental characterizations are presented for a FRP honeycomb panel with sinusoidal core geometry in the plane and extending vertically between face laminates. To verify the accuracy of the a closed-form solution, several honeycomb sandwich beams with sinusoidal core waves either in the longitudinal or transverse directions are tested in bending and torsion. Also, a deck panel …
Efficient Finite Element Modeling Of Wt Sections Subjected To Uniaxial Tension, Ramanand V. Nukala
Efficient Finite Element Modeling Of Wt Sections Subjected To Uniaxial Tension, Ramanand V. Nukala
Graduate Theses, Dissertations, and Problem Reports
Present design specifications for statically loaded tension members do not consider the effects of connection eccentricity as it induces bending in statically loaded members. Previous experimental tests conducted at West Virginia University [WVU] have shown that connection eccentricity induced bending effects have the potential to significantly reduce the net section rupture capacity of a section.;The present study is focused on developing finite element tools capable of capturing the peak loads and behavioral response exhibited is the previous WVU experimental tests. The main objective of the finite element analysis is not only to estimate the failure loads of the WT section …