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2009

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Articles 3511 - 3540 of 7616

Full-Text Articles in Physical Sciences and Mathematics

Characterization Of Microwave Cavity Discharges In A Supersonic Flow, Dareth Janette Drake Apr 2009

Characterization Of Microwave Cavity Discharges In A Supersonic Flow, Dareth Janette Drake

Physics Theses & Dissertations

A partially ionized gas is referred to as either a plasma or a discharge depending on the degree of ionization. The term discharge is usually applied to a weakly ionized gas, i.e. mostly neutrals, where as a plasma usually has a larger degree of ionization. To characterize a discharge the plasma parameters, such as the rotational temperature, vibrational temperature, and electron density, must be determined. Detailed characterization of supersonic flowing discharges is important to many applications in aerospace and aerodynamics. One application is the use of plasma-assisted hydrogen combustion devices to aid in supersonic combustion. In conditions close to the …


A Hurricane Evacuation Route System Real-Time Monitoring And Distribution Of Load, Anup Khanal Apr 2009

A Hurricane Evacuation Route System Real-Time Monitoring And Distribution Of Load, Anup Khanal

Electrical & Computer Engineering Theses & Dissertations

Hurricane evacuation is one of the major steps in diminishing the devastating effects of hurricanes on lives and properties. The challenge in evacuating a large number of people in a short time is the severe congestion faced in the transportation network, leading to long delays and shortages. Standard hurricane evacuation plans focus on how to best utilize the main arteries. The research challenge is to not overload the fastest routes and to utilize all the routes efficiently. The evacuation routing system proposed in this thesis focuses on distributing the traffic load throughout the network, utilizing alternative routes not considered in …


Analysis Of Electroencephalogram Signals For The Identification Of Mental Tasks, My Thy Thi Tran Apr 2009

Analysis Of Electroencephalogram Signals For The Identification Of Mental Tasks, My Thy Thi Tran

Electrical & Computer Engineering Theses & Dissertations

Electroencephalogram (EEG) signals can be used for implicit communication such as to control robots or medical equipment by brain activity or to detect an individual's intentions of committing premeditated crimes. An EEG based brain-computer interface allows paralyzed patients to express their thoughts. However, biological and technical artifacts heavily interfered with EEG signals due to blinking of the eyes, muscle activities and line noise. Sometimes the noise interference due to signal artifacts becomes more prominent than the information content. This thesis investigates novel feature extraction methodologies in EEG signals to represent different thought processes and employs neural network-based pattern classification techniques …


A Bio-Optical Model For Syringodium Filiforme Canopies, Margaret A. Stoughton Apr 2009

A Bio-Optical Model For Syringodium Filiforme Canopies, Margaret A. Stoughton

OES Theses and Dissertations

Seagrasses are significant ecological and biogeochemical agents in shallow water ecosystems throughout the world. In many regions, seagrass meadows occupy a sufficient fraction of the coastal zone, and generate optical signatures that can be observed from space. Bio-optical models of light absorption and scattering by submerged plant canopies for certain species such as Thalassia testudinum and Zostera marina have successfully modeled the plane irradiance distribution and photosynthesis within the submerged canopies. Syringodium filiforme differs &om T. testudinttm and Z marina, in leaf morphology and canopy architecture. The objective of this study was to develop a radiative transfer model that …


Tree-D-Seek: A Framework For Retrieving Three-Dimensional Scenes, Saurav Mazumdar Apr 2009

Tree-D-Seek: A Framework For Retrieving Three-Dimensional Scenes, Saurav Mazumdar

Electrical & Computer Engineering Theses & Dissertations

In this dissertation, a strategy and framework for retrieving 3D scenes is proposed. The strategy is to retrieve 3D scenes based on a unified approach for indexing content from disparate information sources and information levels. The TREE-D-SEEK framework implements the proposed strategy for retrieving 3D scenes and is capable of indexing content from a variety of corpora at distinct information levels. A semantic annotation model for indexing 3D scenes in the TREE-D-SEEK framework is also proposed. The semantic annotation model is based on an ontology for rapid prototyping of 3D virtual worlds.

With ongoing improvements in computer hardware and 3D …


Factors Affecting Adult Foraging And Chick Growth Of Adélie Penguins (Pygoscelis Adeliae) Off The Western Antarctic Peninsula: A Modeling Study, Erik W. Chapman Apr 2009

Factors Affecting Adult Foraging And Chick Growth Of Adélie Penguins (Pygoscelis Adeliae) Off The Western Antarctic Peninsula: A Modeling Study, Erik W. Chapman

OES Theses and Dissertations

Coupled individual-based models that simulate Adélie penguin ( Pygoscelis adeliae) chick growth and adult foraging behavior during the chick growth period were developed and used to explore factors that influence chick fledging mass and adult foraging energetics off the western Antarctic Peninsula (WAP). Adélie penguin colonies in this region are undergoing changes in population size that have been correlated with climate-driven alteration of the marine and terrestrial environment. Simulations were selected to highlight possible mechanistic linkages between climate variability and chick growth and adult foraging processes. These processes were the focus of this study because chicks that fledge at …


Characterization Of Antibiotic Resistance In Vibrio Cholerae Isolated From Ships' Ballast And Other Environmental Sources, Frank Kornegay Thomson Iii Apr 2009

Characterization Of Antibiotic Resistance In Vibrio Cholerae Isolated From Ships' Ballast And Other Environmental Sources, Frank Kornegay Thomson Iii

OES Theses and Dissertations

Ships' ballast has been implicated as a vector in the dispersal of invasive species into new environments. Numerous cases have been documented for the introduction of macroorganisms via ballasting operations, but what is less known is the role of ballast water and residuals in the spread of potentially harmful microbes, especially with reference to novel genotypes. Of particular interest are the genes encoding for various forms of antibiotic resistance, many of which are carried on mobile genetic elements. A four-year sampling effort has yielded over 300 putative isolates of Vibrio cholerae from ships' ballast tanks and various environmental sources, of …


On The Role Of Assertions For Conceptual Modeling As Enablers Of Composable Simulation Solutions, Robert Dennis King Apr 2009

On The Role Of Assertions For Conceptual Modeling As Enablers Of Composable Simulation Solutions, Robert Dennis King

Computational Modeling & Simulation Engineering Theses & Dissertations

This research provides a much needed systematic review of the roles that assertions play in model composability and simulation interoperability. In doing so, this research contributes a partial solution to one of the problems of model composability and simulation interoperability—namely, why do simulation systems fail to achieve the maximum level of interoperability possible? It demonstrates the importance of the assertions that are made during model development and simulation implementation, particularly as they reflect the unique viewpoint of each developer or user. It hypothesizes that it is possible to detect composability conflicts by means of a four-step process developed by the …


A Compact Lidar For Aircraft Ozone Atmospheric Measurements, Joel A. Marcia Apr 2009

A Compact Lidar For Aircraft Ozone Atmospheric Measurements, Joel A. Marcia

Electrical & Computer Engineering Theses & Dissertations

Researchers and the general public have expressed great concern over how human activities exacerbate pollution's deteriorating impact upon the environment. Effects such as global warming, air quality and ozone layer depletion are but a few examples that can have a dramatic effect on the quality of life worldwide.

A compact lidar system for the purpose of aircraft ozone atmospheric measurements was tested and evaluated. This system will eventually be deployed for aircraft-based, and possibly unpiloted atmospheric vehicle (UAV), ozone and aerosol measurements to improve our understanding of ozone production and transport. Each of the major subsystems was characterized and from …


A Hidden Markov Model Based Approach To Detect Rogue Access Points, Gayathri Shivaraj Apr 2009

A Hidden Markov Model Based Approach To Detect Rogue Access Points, Gayathri Shivaraj

Electrical & Computer Engineering Theses & Dissertations

One of the most challenging security concerns for network administrators is the presence of Rogue access points. The challenge is to detect and disable a Rogue access point before it can cause hazardous damage to the network. This thesis proposes a statistically based approach to detect Rogue access points using a Hidden Markov Model, which is applied to passively measure packet-header data collected at a gateway router or any monitoring point. This approach utilizes variations in packet inter-arrival time to differentiate between authorized access points and Rouge access points. This approach used the inter-arrival time of a packet as a …


Characterization Of Metal-Reducing Enzymes Expressed By The Bacterium Shewanella Algae: Gene Sequencing, Thomas Goyne, Changmo Sohn, Sarah Tesch, Jonathan Penny Mar 2009

Characterization Of Metal-Reducing Enzymes Expressed By The Bacterium Shewanella Algae: Gene Sequencing, Thomas Goyne, Changmo Sohn, Sarah Tesch, Jonathan Penny

Thomas Goyne

No abstract provided.


Interregional Comparison Of Karst Disturbance: West-Central Florida And Southeast Italy, Leslie North Mar 2009

Interregional Comparison Of Karst Disturbance: West-Central Florida And Southeast Italy, Leslie North

Leslie North

The karst disturbance index (KDI) consists of 31 environmental indicators contained within the five broad categories: geomorphology, hydrology, atmosphere, biota, and cultural. The purpose of this research is to apply the KDI to two distinct karst areas, west Florida, USA, and Apulia, Italy. Through its application, the utility of the index can be validated and other important comparisons can be made, such as differences in the karst legislations implemented in each region and the effect of time exposure to human occupation to each karst terrain. Humans have intensively impacted the karst of southeast Italy for thousands of years compared to …


Cloud Computing: New Wine Or Just A New Bottle?, Jia Zhang, Jeffrey Voas Mar 2009

Cloud Computing: New Wine Or Just A New Bottle?, Jia Zhang, Jeffrey Voas

Jia Zhang

No abstract provided.


Affective Game Engines: Motivation And Requirements, Eva Hudlicka Mar 2009

Affective Game Engines: Motivation And Requirements, Eva Hudlicka

Eva Hudlicka

The tremendous advances in gaming technologies over the past decade have focused primarily on the physical realism of the game environment and game characters, and the complexity and performance of game simulations and networking. However, current games are still lacking in the affective realism of the game characters, and the social complexity and realism of their interactions. To achieve the next leap in the level of engagement and effectiveness, particularly in the arena of serious games, gaming research needs to focus on enhancing the social and affective complexity and realism of the game characters, their interaction, and the game narrative …


Basic Math Skills: Can High School Students Do The Math?, Samantha Sebastian Mar 2009

Basic Math Skills: Can High School Students Do The Math?, Samantha Sebastian

Leah A. Nillas

This article examined high school students’ basic mathematics skills. 126 Students participated in a study that lasted ten weeks in which a pretest and post-test were taken. In between the tests, students took weekly quizzes to refresh and relearn the following basic mathematics skills: adding, subtracting, multiplying, and dividing whole numbers, decimals, and fractions; proportions; conversion between percents, decimals, and fractions; and order of operations. The scores of the pretest and post-test were analyzed to see if improvements were made. Scores were compared by gender and grade level. The study showed an overall improvement on students’ ability to do basic …


Breaking Language Barriers: Connections Between Foreign Language And English Language Arts, Lauren Booth, '09 Mar 2009

Breaking Language Barriers: Connections Between Foreign Language And English Language Arts, Lauren Booth, '09

Leah A. Nillas

The purpose of this study was to investigate the relationships between foreign language and English language arts. In previous literature, foreign language has been shown to positively affect students' performance in other subject areas as well as developing their cognitive abilities. When I thought about my own teaching experiences, I made direct connections between foreign language and English language arts in terms of vocabulary acquisition and grammar. Through interviews I found that other teachers are also aware of those connections and deliberately use them to enhance their instruction and defend the study of a foreign language. Upon investigating foreign language …


The Impact Of Extracurricular Activities On High School Students’ Academic Success, Nicholas Cooprider Mar 2009

The Impact Of Extracurricular Activities On High School Students’ Academic Success, Nicholas Cooprider

Leah A. Nillas

“Although we cannot conclude from the data that extracurricular activities alone caused these improvements, we can say with virtual certainty that when we help a student move from no participation in extracurricular activities to engagement in three or four such activities, it does not harm academic performance” (Reeves, 2008, p.2). Previous research concluded that participation in extracurricular activities does correlate to academic achievement in the classroom. This research examined how students perceived their involvement in extracurricular activities affected their academic performance. Surveys were distributed to a local, rural high school and students were asked to document the amount of time …


Analytical Solution For Stokes Flow Inside An Evaporating Sessile Drop: Spherical And Cylindrical Cap Shapes, Hassan Masoud, James D. Felske Mar 2009

Analytical Solution For Stokes Flow Inside An Evaporating Sessile Drop: Spherical And Cylindrical Cap Shapes, Hassan Masoud, James D. Felske

Hassan Masoud

Exact analytical solutions are derived for the Stokes flows within evaporating sessile drops of spherical and cylindrical cap shapes. The results are valid for all contact angles. Solutions are obtained for arbitrary evaporative flux distributions along the free surface as long as the flux is bounded at the contact line. Specific results and computations are presented for evaporation corresponding to uniform flux and to purely diffusive gas phase transport into an infinite ambient. Wetting and nonwetting contact angles are considered with the flow patterns in each case being illustrated. For the spherical cap with evaporation controlled by vapor phase diffusion, …


Smoothing Parameter Selection For A Class Of Semiparametric Linear Models, Philip T. Reiss, R. Todd Ogden Mar 2009

Smoothing Parameter Selection For A Class Of Semiparametric Linear Models, Philip T. Reiss, R. Todd Ogden

Philip T. Reiss

Spline-based approaches to nonparametric and semiparametric regression, as well as to regression of scalar outcomes on functional predictors, entail choosing a parameter controlling the extent to which roughness of the fitted function is penalized. In this paper we demonstrate that the equations determining two popular methods for smoothing parameter selection, generalized cross-validation and restricted maximum likelihood, share a similar form that allows us to prove several results common to both, and to derive a condition under which they yield identical values. These ideas are illustrated by application of functional principal component regression, a method for regressing scalars on functions, to …


Landscape Ecology On College Campuses To Promote Environmental Sustainability, Erin Stempinski Mar 2009

Landscape Ecology On College Campuses To Promote Environmental Sustainability, Erin Stempinski

Undergraduate Research Conference

No abstract provided.


Stereospecific Enzyme Isolation From Carrots, Jacqueline Greer, Eileen Rigsby Mar 2009

Stereospecific Enzyme Isolation From Carrots, Jacqueline Greer, Eileen Rigsby

Undergraduate Research Conference

No abstract provided.


Solids Of Revolution About The Line Y=Mx, Harvey Marquis Iii Mar 2009

Solids Of Revolution About The Line Y=Mx, Harvey Marquis Iii

Undergraduate Research Conference

No abstract provided.


Biodiesel: Tomorrow's Fuel, Today's Solution, Roberto J. Molina, Racheal A. Persuad Mar 2009

Biodiesel: Tomorrow's Fuel, Today's Solution, Roberto J. Molina, Racheal A. Persuad

Undergraduate Research Conference

Study of physical and chemical properties of biodiesel fuels derived from poultry and plant fats.


Going Green Makes Cents!, Anthony Caldwell, Logan Fountain, Tiffany Snider Mar 2009

Going Green Makes Cents!, Anthony Caldwell, Logan Fountain, Tiffany Snider

Undergraduate Research Conference

No abstract provided.


The Road To Leed Certification: Human Sciences South, Claire Collins, Kim Stockley, Whitney Kirkland Mar 2009

The Road To Leed Certification: Human Sciences South, Claire Collins, Kim Stockley, Whitney Kirkland

Undergraduate Research Conference

Leadership in Energy and Environmental Design for Existing Buildings a set number of voluntary standards. LEED EB focuses on the performance of a building rather than it’s design.


The Green Business Revolution, Jacob Martin, Penny Mcclendon, Brian Watson, Jimanna Watson Mar 2009

The Green Business Revolution, Jacob Martin, Penny Mcclendon, Brian Watson, Jimanna Watson

Undergraduate Research Conference

No abstract provided.


Communication Across Random Landings, Kerron Joseph, Jay Walbran Mar 2009

Communication Across Random Landings, Kerron Joseph, Jay Walbran

Undergraduate Research Conference

The idea to do this project began with a simple question: Suppose that people carrying communication radios parachute out of a plane, if each device has a certain range, what is the probability that once everyone lands they will be able to communicate. To study this problem I assumed that the spot where each individual lands is normally distributed.

We discuss the different ways the communication radios can work. In particular we examine the situation where all the radios have to be within a certain radius r to operate correctly and the situation where the radios work on a relay …


Spectroscopic Studies Of Fluoranthene And 3-Nitrofluoranthene, Matthew Parks Mar 2009

Spectroscopic Studies Of Fluoranthene And 3-Nitrofluoranthene, Matthew Parks

Undergraduate Research Conference

Polycyclic aromatic hydrocarbons (PAHs) are known byproducts of anthropogenic sources including incomplete combustion of fossil fuels. They are known to be teratogenic, mutagenic and carcinogenic. This study investigated the spectral properties of fluoranthene and 3- nitrofluoranthene using NMR, UV-Vis and infrared techniques. The acquisition of spectral data provides a means to identify these compounds in mixtures and can be used which to develop model formulae for quantitation. A 2-D NMR method (HMQC ) was used for assigning 13C peaks. The infrared spectrum for 3-nitrofluoranthene showed characteristic strong absorption peaks at 1323 and 1516 cm-1 assigned to symmetric/asymmetric nitro stretches, respectively. …


Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering January 1, 2009 – March 31, 2009, Margaret N. Rees Mar 2009

Nevada Interagency Volunteer Program: Helping Hands Across Public Lands – Phase Ii: Quarterly Progress Report, Period Covering January 1, 2009 – March 31, 2009, Margaret N. Rees

Get Outdoors Nevada

  • The number of records in the volunteer database increased by 3.5%.
  • A total of 1,676 database records were archived due to inactivity resulting in a reduction of 26% in the number of current records in the database. The database currently contains 4,957 records.
  • Website activity increased, recording an average of 68,086 hits per month, an increase of 22 % from last quarter, with an average of 5,228 pages viewed per month.
  • The new website design was launched along with the release of a monthly electronic newsletter.
  • How to Succeed with Volunteers training was conducted for SNAP teams and well received …


Topics In Analytic Number Theory, Kevin James Powell Mar 2009

Topics In Analytic Number Theory, Kevin James Powell

Theses and Dissertations

The thesis is in two parts. The first part is the paper “The Distribution of k-free integers” that my advisor, Dr. Roger Baker, and I submitted in February 2009. The reader will note that I have inserted additional commentary and explanations which appear in smaller text. Dr. Baker and I improved the asymptotic formula for the number of k-free integers less than x by taking advantage of exponential sum techniques developed since the 1980's. Both of us made substantial contributions to the paper. I discovered the exponent in the error term for the cases k=3,4, and worked the case k=3 …