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2007

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Articles 12541 - 12560 of 12560

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Belongingness And Integrative Motivation In Second Language Acquisition, Robb. Kvasnak Jan 2007

Belongingness And Integrative Motivation In Second Language Acquisition, Robb. Kvasnak

Electronic Theses and Dissertations 2000 - 2009

This study investigates the perceptions that second language students have of those who speak the language that these students are trying to acquire and examines how these perceptions relate to students' progress in acquiring the target language. The study is based on the psychological theory of the need to belong, i.e. belongingness as well as on the concept of integrative motivation. This study is a qualitative investigation that uses the Repertory Grid Technique and Personal Construct Theory in order to elicit subject perceptions and their constructs. Membership checking was carried out with nine of the originally interviewed 22 subjects in …

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Maximizing Single Opposition Observations Of Asteroids, Steven J. Higley Jan 2007

Maximizing Single Opposition Observations Of Asteroids, Steven J. Higley

Theses and Dissertations

No abstract provided.

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A Precision Positioning Actuator System Using A Pid Controller, Vipin A. Guda Jan 2007

A Precision Positioning Actuator System Using A Pid Controller, Vipin A. Guda

Theses and Dissertations

No abstract provided.

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The Florida Comprehensive Assessment Test (Fcat) And The Predictive Utility Of The Psat For Fcat Preparedness, Bernadine E Dorantes Beard Jan 2007

The Florida Comprehensive Assessment Test (Fcat) And The Predictive Utility Of The Psat For Fcat Preparedness, Bernadine E Dorantes Beard

Electronic Theses and Dissertations 2000 - 2009

In the years since the establishment of the Florida Comprehensive Assessment test (FCAT) in 1998, the Florida public school districts have had little standardized, diagnostic data to assist in preparation for the FCA T. The FCAT serves as a high-stakes assessment for students as a graduation requirement, and it serves as a high-stakes assessment for school and district accountability for the Florida A++ Plan, and for national accountability within No Child Left Behind Act, 2001. A quantitative study was conducted to determine if the College Board's Preliminary Scholastic Achievement Test, PSAT/NMSQT®, could be used to predict scores on the FCAT. …

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The Impact Of A Museum-Based Science Methods Course On Early Childhood/Elementary Pre-Service Teachers' Self-Efficacy And Ability To Develop Curriculum Using A Constructivist Approach, Chelneca Kegley Templeton Jan 2007

The Impact Of A Museum-Based Science Methods Course On Early Childhood/Elementary Pre-Service Teachers' Self-Efficacy And Ability To Develop Curriculum Using A Constructivist Approach, Chelneca Kegley Templeton

Electronic Theses and Dissertations 2000 - 2009

The focus of this study was to discover what impact a museum-based science methods course would have on 14 early childhood/elementary pre-service teachers' selfefficacy and ability to develop curriculum using a constructivist approach. Data were gathered using the STEBI-B, modified by Bleicher (2004). A paired-samples t test indicated there was significant change in the pre-service teachers ' self-efficacy pre-and post-museum course participation. The investigation also analyzed student-created learning centers intended for use in the students' future classrooms. Students created two learning centers, one before interaction with exhibits in the museum and one at the end of the course. At the …

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Boundary Layer Control On A Circular Cylindrical Body Through Oscillating Lorentz Forcing, Ryan K. Seltzer Jan 2007

Boundary Layer Control On A Circular Cylindrical Body Through Oscillating Lorentz Forcing, Ryan K. Seltzer

Electronic Theses and Dissertations 2000 - 2009

Boundary layer control on a circular cylindrical body through oscillating Lorentz forcing is studied by means of numerical simulation of the vorticity-stream function formulation of the Navier-Stokes equations. The model problem considers axisymmetric seawater flow along an infinite cylinder controlled by an idealized radially directed Lorentz force oscillating spatially and temporally. Under optimum forcing parameters, it is shown that sustainable Lorentz induced vortex rings can travel along the cylinder at a speed equivalent to the phase speed of forcing . Wall stress is shown to locally change sign in the region adjacent to the vortex, considerably decreasing net viscous drag …

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Body Condition Of Juvenile Hoplosternum Littorale (Hancock, 1828) In Anthropogenic Refuges On The Big Cypress Seminole Indian Reservation During The 2006 Dry Season, Gianna Ramdin Jan 2007

Body Condition Of Juvenile Hoplosternum Littorale (Hancock, 1828) In Anthropogenic Refuges On The Big Cypress Seminole Indian Reservation During The 2006 Dry Season, Gianna Ramdin

Electronic Theses and Dissertations 2000 - 2009

This study investigated variations m body condition of brown hoplos (Hoplosternum littorale) refuging in ponds in the Big Cypress region of southern Florida. During the dry season environmental parameters fluctuated, water depth and dissolved oxygen decreased, while temperature and conductivity increased. Standard lengths and wet weights of 675 juvenile brown hoplos were measured from seven populations. Body condition was compared between populations and through time (early vs. late dry season) using length-weight relationship and Fulton's condition factor. The only significant spatia-temporal variations in body condition occurred in the deepest refuges. One population demonstrated an unexpected positive change in body condition, …

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Brain Computer Interface And Neuroprosthetics, Rodrigo Calderon Jan 2007

Brain Computer Interface And Neuroprosthetics, Rodrigo Calderon

Electronic Theses and Dissertations 2000 - 2009

For many years people have consider the possibility that brain activity might provide a new channel for communication between a person's brain and the external world. Brain Computer Interface allows humans to control electronic devices using only their thoughts. The goal of this project is to provide the users with a basic control of a prosthetic arm using the signal acquired by an Electroencephalogram (EEG). The main objective of the research is to demonstrate and provide a system that allows individuals to obtain control of the device with very little training and very few electrodes. The research includes the development …

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Characteristics Affecting Prey Vulnerability And Avian Habitat Selection In The Florida Everglades, Rachael L. Harris Jan 2007

Characteristics Affecting Prey Vulnerability And Avian Habitat Selection In The Florida Everglades, Rachael L. Harris

Electronic Theses and Dissertations 2000 - 2009

The vulnerability of prey to capture plays a fundamental role in determining overall prey availability for wading birds. Structural complexity can act to decrease prey vulnerability and influence foraging habitat selection. To determine how structural complexity can affect habitat selection I conducted a use vs. availability study throughout the Florida Everglades in 2005 and 2006. Results indicated that wading birds chose foraging sites that had less emergent vegetation and a thicker flocculent layer relative to random sites. Submerged vegetation, and the height of emergent vegetation did not affect wading bird site selection. A difference in habitat selection between years was …

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Developing Healthy Kids In Healthy Communities: Eight Evidence-Based Strategies For Preventing High-Risk Behaviour., Gary L. Hopkins, Duane C. Mcbride, Helen H. Marshak, Kiti Freier, John V. Stevens, Wendi Kannenberg, James B. Weaver, Stephanie L. Sargent Weaver, Peter N. Landless, Jonathan Duffy Jan 2007

Developing Healthy Kids In Healthy Communities: Eight Evidence-Based Strategies For Preventing High-Risk Behaviour., Gary L. Hopkins, Duane C. Mcbride, Helen H. Marshak, Kiti Freier, John V. Stevens, Wendi Kannenberg, James B. Weaver, Stephanie L. Sargent Weaver, Peter N. Landless, Jonathan Duffy

Faculty Publications

Australian youth engage in behaviour that threatens their health and wellbeing. National surveys report that about a third of young Australians have tried an illicit drug. High rates of substance use and risky sexual behaviour among young Australians suggest that effective prevention efforts based on empirical evidence need to be expanded. Church-associated organisations are an untapped resource that could be used to improve the health and welfare of young people. We describe eight evidence-based elements to consider in designing strategies to prevent high-risk behaviour in young people.

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Search For Gravitational-Wave Bursts In Ligo Data From The Fourth Science Run, B. Abbott, R. Abbott, R. Adhikari, J. Agresti, P. Ajith, B. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. Arain, M. Araya, H. Armandula, M. Ashley, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, K. Bayer, K. Belczynski, J. Betzwieser, P. T. Beyersdorf, B. Bhawal, I. A. Bilenko, Tiffany Z. Summerscales Jan 2007

Search For Gravitational-Wave Bursts In Ligo Data From The Fourth Science Run, B. Abbott, R. Abbott, R. Adhikari, J. Agresti, P. Ajith, B. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. Arain, M. Araya, H. Armandula, M. Ashley, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, K. Bayer, K. Belczynski, J. Betzwieser, P. T. Beyersdorf, B. Bhawal, I. A. Bilenko, Tiffany Z. Summerscales

Faculty Publications

The fourth science run of the LIGO and GEO 600 gravitational-wave detectors, carried out in early 2005, collected data with significantly lower noise than previous science runs. We report on a search for short-duration gravitational-wave bursts with arbitrary waveform in the 64-1600 Hz frequency range appearing in all three LIGO interferometers. Signal consistency tests, data quality cuts and auxiliary-channel vetoes are applied to reduce the rate of spurious triggers. No gravitational-wave signals are detected in 15.5 days of live observation time; we set a frequentist upper limit of 0.15 day-1 (at 90% confidence level) on the rate of bursts with …

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Measurement Of Prompt Photons With Associated Jets In Photoproduction At Hera, S. Chekanov, M. Derrick, S. Magill, S. Miglioranzi, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, L. Rinaldi, G. Sartorelli Jan 2007

Measurement Of Prompt Photons With Associated Jets In Photoproduction At Hera, S. Chekanov, M. Derrick, S. Magill, S. Miglioranzi, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, N. Pavel, A. G. Yagües Molina, S. Antonelli, P. Antonioli, G. Bari, M. Basile, L. Bellagamba, M. Bindi, D. Boscherini, A. Bruni, G. Bruni, L. Cifarelli, F. Cindolo, A. Contin, M. Corradi, S. De Pasquale, G. Iacobucci, A. Margotti, R. Nania, A. Polini, L. Rinaldi, G. Sartorelli

Faculty Publications

The photoproduction of prompt photons, together with an accompanying jet, has been studied in ep collisions at a centre-of-mass energy of 318 GeV with the ZEUS detector at HERA using an integrated luminosity of 77 pb-1. Cross sections were measured for the transverse energy of the photon and the jet larger than 5 and 6 GeV, respectively. The differential γ+jet cross sections were reconstructed as functions of the transverse energy, pseudorapidity and xγobs, the fraction of the incoming photon momentum taken by the photon-jet system. Predictions based on leading-logarithm parton-shower Monte Carlo models and next-to-leading-order (NLO) QCD generally underestimate the …

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Novel Concepts For Enhanced Nuclear Thermal Propulsion Using Flow Area Tailoring And A Grooved-Ring Core Design, Julien Michel Apeloig Jan 2007

Novel Concepts For Enhanced Nuclear Thermal Propulsion Using Flow Area Tailoring And A Grooved-Ring Core Design, Julien Michel Apeloig

Theses and Dissertations

The most likely candidate for human missions to Mars and beyond will be spacecraft using Nuclear Thermal Propulsion (NTP). NTP provides for high thrust-to-weight ratio and significantly improved specific impulse over even the best chemical rockets. The improved specific impulse reduces required trip times, thereby minimizing the exposure time of the crew to space radiation. Using the PHOEBUS 2A 5 GW reactor, developed in the 1960’s with a thrust of 1,113 N and a specific impulse of 820 s, as a basis for comparison this thesis focuses on efforts to improve the specific impulse and reactor longevity. Hydrogen is the …

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First Passage Time Problem For Multivariate Jump-Diffusion Processes: Models, Computation, And Applications In Finance, Di Zhang Jan 2007

First Passage Time Problem For Multivariate Jump-Diffusion Processes: Models, Computation, And Applications In Finance, Di Zhang

Theses and Dissertations (Comprehensive)

The first passage time (FPT) problems are ubiquitous in many applications, from physics to finance. Mathematically, such problems are often reduced to the evaluation of the probability density of the time for a process to cross a certain level, a boundary, or to enter a certain region. While in other areas of applications the FPT problems can often be solved analytically, in finance we usually have to resort to the application of numerical procedures, in particular when we deal with jump-diffusion stochastic processes (JDP). The application of the conventional Monte-Carlo procedure is possible for the solution of the resulting model, …

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Optimal Neuro-Fuzzy External Controller For A Statcom In The 12-Bus Benchmark Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 2007

Optimal Neuro-Fuzzy External Controller For A Statcom In The 12-Bus Benchmark Power System, Salman Mohagheghi, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

An optimal neuro-fuzzy external controller is designed in this paper for a static compensator (STATCOM) in the 12-bus benchmark power system. The controller provides an auxiliary reference signal for the STATCOM in such a way that it improves the damping of the rotor speed deviations of its neighboring generators. A Mamdani fuzzy rule base constitutes the core of the controller. A heuristic dynamic programming-based approach is used to further train the controller and enable it to provide nonlinear optimal control at different operating conditions of the power system. Simulation results are provided that indicate the proposed neuro-fuzzy external controller is …

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Life Without Water : Expression Of Plant Lea Genes By An Anhydrobiotic Arthropod., Steven Hand, Dana Jones, Michael Menze, Trudy Witt Jan 2007

Life Without Water : Expression Of Plant Lea Genes By An Anhydrobiotic Arthropod., Steven Hand, Dana Jones, Michael Menze, Trudy Witt

Faculty and Staff Scholarship

Anhydrobiotic animals protect cellular architecture and metabolic machinery in the dry state, yet the molecular repertoire supporting this profound dehydration tolerance is not fully understood. For the desiccation-tolerant crustacean, Artemia franciscana, we report differential expression of two distinct mRNAs encoding for proteins that share sequence similarities and structural features with late-embryogenesis abundant (LEA) proteins originally discovered in plants. Bioinformatic analyses support assignment of the LEA proteins from A. franciscana to group 3. This eucoelomate species is the most highly evolved animal for which LEA gene expression has been reported. It is becoming clear that an ensemble of micromolecules and macromolecules …

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Development Of Test Paradigms For Operant Conditioning Of Wild Norway Rats, Susan M. Jojola, Patrick W. Burke, Gary W. Witmer, Dale L. Nolte Jan 2007

Development Of Test Paradigms For Operant Conditioning Of Wild Norway Rats, Susan M. Jojola, Patrick W. Burke, Gary W. Witmer, Dale L. Nolte

United States Department of Agriculture Wildlife Services: Staff Publications

Many eradication efforts to remove rats (Rattus spp.) from islands have been successful. Eradications are expensive and labor-intensive which makes early detection of, and response to, reinvasion by rats critical. A better understanding of rat behavior could facilitate early detection and rapid response to intercept invaders, such as with trap placement and design, and toxic bait presentation and dispersal. This was a methods development study of test paradigms to operantly condition wild rats to run on an activity wheel and to press a lever for use in future behavior studies. Operant conditioning is the process of associating specific responses …

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The Art Of The Letter, Rothanak Chhoun Jan 2007

The Art Of The Letter, Rothanak Chhoun

Undergraduate Theses and Senior Projects

No abstract provided.

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Reservoir Characterization Of The Broom Creek Formation For Carbon Dioxide Sequestration, Justin J. Kringstad Jan 2007

Reservoir Characterization Of The Broom Creek Formation For Carbon Dioxide Sequestration, Justin J. Kringstad

Undergraduate Theses and Senior Projects

This engineering design is aimed at providing a thorough investigation on the potential of carbon dioxide (CO2) sequestration in the Williston Basin’s Broom Creek Formation. The objective of the design is to characterize the Broom Creek’s reservoir properties and provide detailed results of CO2 sequestration capacity, plume migration, and safety level. The methodology used to obtain results is an incorporation of geology, reservoir engineering, and injection operations. The reservoir simulation operations were conducted using Schlumberger’s ECLIPSE (Schlumberger, 2006).

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Multiple Mixed-Type Attractors In A Competition Model, J. M. Cushing, Shandelle M. Henson, Chantel C. Blackburn Jan 2007

Multiple Mixed-Type Attractors In A Competition Model, J. M. Cushing, Shandelle M. Henson, Chantel C. Blackburn

Faculty Publications

We show that a discrete-time, two-species competition model with Ricker (exponential) nonlinearities can exhibit multiple mixed-type attractors. By this is meant dynamic scenarios in which there are simultaneously present both coexistence attractors (in which both species are present) and exclusion attractors (in which one species is absent). Recent studies have investigated the inclusion of life-cycle stages in competition models as a casual mechanism for the existence of these kinds of multiple attractors. In this paper we investigate the role of nonlinearities in competition models without life-cycle stages. © 2007 Taylor & Francis Group, LLC.

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