Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

University of Central Florida

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 5101 - 5130 of 7705

Full-Text Articles in Entire DC Network

Teacher Performance Pay: The Perceptions Of Certified School-Based Pe, Gregory Adkins Jan 2004

Teacher Performance Pay: The Perceptions Of Certified School-Based Pe, Gregory Adkins

Electronic Theses and Dissertations

To meet the continued demand for educational reform, the state of Florida enacted legislation in 1998 that required school boards to base a portion of the salary for school administrators and instructional personnel on performance. Although ahead of the required statutory timeline, the School District of Lee County implemented a teacher performance pay plan during the 1998–1999 school year as a result of Florida's legislative direction. The problem of this study was to determine the perceptions of Southwest Florida school-based certified staff regarding the implementation of teacher performance pay in a school district where performance pay had been in operation …

Go to article

'A Man's World'?: A Study Of Female Workers At Nasa's Kennedy Space C, Nanci Schwartz Jan 2004

'A Man's World'?: A Study Of Female Workers At Nasa's Kennedy Space C, Nanci Schwartz

Electronic Theses and Dissertations

By focusing on women workers at NASA's Kennedy Space Center in Florida, this study seeks to understand why women were initially congregated in certain occupations such as clerical work and later moved into non-traditional jobs such as engineering and the sciences. Such an investigation requires careful examination of the changing attitudes towards female workers in technical or non-traditional fields and why and how those attitudes changed over time and the extent to which this occurred. It also attempts to identify areas of continuing concern. The study reveals that several factors contributed to the women's progress in the workplace. These included …

Go to article

Monolithic Integration Of Dual Optical Elements On High Power Semicond, Laurent Vaissie Jan 2004

Monolithic Integration Of Dual Optical Elements On High Power Semicond, Laurent Vaissie

Electronic Theses and Dissertations

This dissertation investigates the monolithic integration of dual optical elements on high power semiconductor lasers for emission around 980nm wavelength. In the proposed configuration, light is coupled out of the AlGaAs/GaAs waveguide by a low reflectivity grating coupler towards the substrate where a second monolithic optical element is integrated to improve the device performance or functionality. A fabrication process based on electron beam lithography and plasma etching was developed to control the grating coupler duty cycle and shape. The near-field intensity profile outcoupled by the grating is modeled using a combination of finite-difference time domain (FDTD) analysis of the nonuniform …

Go to article

Data Transmission Scheduling For Distributed Simulation Using Packet A, Juan Vargas-Morales Jan 2004

Data Transmission Scheduling For Distributed Simulation Using Packet A, Juan Vargas-Morales

Electronic Theses and Dissertations

Communication bandwidth and latency reduction techniques are developed for Distributed Interactive Simulation (DIS) protocols. Using logs from vignettes simulated by the OneSAF Testbed Baseline (OTB), a discrete event simulator based on the OMNeT++ modeling environment is developed to analyze the Protocol Data Unit (PDU) traffic over a wireless flying Local Area Network (LAN). Alternative PDU bundling and compression techniques are studied under various metrics including slack time, travel time, queue length, and collision rate. Based on these results, Packet Alloying, a technique for the optimized bundling of packets, is proposed and evaluated. Packet Alloying becomes more active when it is …

Go to article

A Software-Based Knowledge Management System Using Narrative Texts, Thomas Rudy Mcdaniel Jan 2004

A Software-Based Knowledge Management System Using Narrative Texts, Thomas Rudy Mcdaniel

Electronic Theses and Dissertations

Technical and professional communicators have in recent research been challenged to make significant contributions to the field of knowledge management, and to learn or create the new technologies allowing them to do so. The purpose of this dissertation is to make such a combined theoretical and applied contribution from the context of the emerging discipline of Texts and Technology. This dissertation explores the field of knowledge management (KM), particularly its relationship to the related study of artificial intelligence (AI), and then recommends a KM software application based on the principles of narratology and narrative information exchange. The focus of knowledge …

Go to article

Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang Jan 2004

Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang

Electronic Theses and Dissertations

Magnetic materials are currently being developed in the areas of pharmacology and medicinal chemistry for use in applications such as drug delivery and magnetic resonance imaging. Magnetic fluids are being used in audio equipment and hard disk drives. Their suspension in a particular fluid is promoted by the adsorption or reaction of steric or electrostatic stabilizers, which are appropriate for the particular medium. Critical to the success of these magnetic fluids is the development of the steric stabilizers, which must prevent the coagulation of the metal particles. Polymeric materials are one of the most suitable nonmagnetic media to disperse the …

Go to article

The Influence Of Students' Cognitive Style On A Standardized Reading Test Administered In Three Different Formats, Elizabeth Lynn Blanton Jan 2004

The Influence Of Students' Cognitive Style On A Standardized Reading Test Administered In Three Different Formats, Elizabeth Lynn Blanton

Electronic Theses and Dissertations

The purpose of this study was to examine the means of scores on three forms of a standardized reading comprehension test taken by community college students in developmental reading classes. The three forms of the test were administered as a timed multiple-choice test, a constructed response test, and an un-timed multiple-choice test. Scores on the Group Embedded Figures Test (GEFT) were used to classify the students who participated in the study as having field dependent (LOW GEFT), mid-field dependent/independent (MID GEFT), or fieldindependent (HIGH GEFT) tendencies. The paired samples test was used to analyze the scores among the students classified …

Go to article

Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat Jan 2004

Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat

Electronic Theses and Dissertations

Light scattering-based techniques are being developed for non-invasive diagnostics of inhomogeneous media in various fields, such as medicine, biology, and material characterization. However, as most media of interest are highly scattering and have a complex structure, it is difficult to obtain a full analytical solution of the scattering problem without introducing approximations and assumptions about the properties of the system under consideration. Moreover, most of the previous studies deal with idealized scattering situations, rarely encountered in practice. This dissertation provides new analytical, numerical, and experimental solutions to describe subtle effects introduced by the properties of the light sources, and by …

Go to article

Optimal Upfc Control And Operations For Power Systems, Xiaohe Wu Jan 2004

Optimal Upfc Control And Operations For Power Systems, Xiaohe Wu

Electronic Theses and Dissertations

The content of this dissertation consists of three parts. In the first part, optimal control strategies are developed for Unified Power Flow Controller (UPFC) following the clearance of fault conditions. UPFC is one of the most versatile Flexible AC Transmission devices (FACTs) that have been implemented thus far. The optimal control scheme is composed of two parts. The first is an optimal stabilization control, which is an open-loop ‘Bang’ type of control. The second is an suboptimal damping control, which consists of segments of ‘Bang’ type control with switching functions the same as those of a corresponding approximate linear system. …

Go to article

The Design And Development Of A Comprehensive 49 Locus Y-Str Database For Major U.S. Populations, Paulina Niki Berdos Jan 2004

The Design And Development Of A Comprehensive 49 Locus Y-Str Database For Major U.S. Populations, Paulina Niki Berdos

Electronic Theses and Dissertations

The establishment of a U.S. National Y-STR reference database from a variety of geographically and ethically diverse populations is essential to facilitate the generation of reliable estimates of Y-STR haplotype frequencies. Such multi-locus haplotype frequencies are required to provide a statistical estimate of the significance of a match. Y-STR loci, unlike traditional STR markers, are not independent of one another and are co-inherited as extended haplotypes of linked markers. The estimation of the frequency of occurrence of a particular haplotype therefore necessitates the use of a counting method, which means that the significance of many matches is dependent upon the …

Go to article

Nascar Restrictor Plate Exhaust Manifold Design Strategies, Matthew John Dollhopf Jan 2004

Nascar Restrictor Plate Exhaust Manifold Design Strategies, Matthew John Dollhopf

Electronic Theses and Dissertations

This paper presents the results of a study on exhaust manifold design for a NASCAR Restrictor plate internal combustion engine. A computer simulation model was developed using Ricardo WAVE software. WAVE is a computer-aided engineering code developed by Ricardo to analyze the dynamics of pressure waves, mass flows and energy losses in ducts, plenums and the intake and exhaust manifolds of various systems and machines. [1] The model was validated against experimental data from a current NASCAR Winston Cup restrictor plate motor. The parameters studied have been exhaust manifold diameters and lengths. A response surface analysis of the simulation output …

Go to article

Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz Jan 2004

Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz

Electronic Theses and Dissertations

Due to increasing demand on deployable surveillance systems in recent years, object tracking and activity recognition are receiving considerable attention in the research community. This thesis contributes to both the tracking and the activity recognition components of a surveillance system. In particular, for the tracking component, we propose two different approaches for tracking objects in video acquired by mobile cameras, each of which uses a different object shape representation. The first approach tracks the centroids of the objects in Forward Looking Infrared Imagery (FLIR) and is suitable for tracking objects that appear small in airborne video. The second approach tracks …

Go to article

Design And Analysis Of Adaptive And Reconfigurable Antennas For Wireless Communication, Maha Abdelmoneim Mohamed Ali Jan 2004

Design And Analysis Of Adaptive And Reconfigurable Antennas For Wireless Communication, Maha Abdelmoneim Mohamed Ali

Electronic Theses and Dissertations

Modern radar and communication systems have experienced a tremendous increase in the number of antennas onboard, on the ground, and in orbital space. This places a burden due to the confined volume and limited weight requirements especially in space applications. The reconfigurable antenna is a promising and exciting new type of antenna, where through the use of appropriate switches the antenna can be structurally reconfigured, to maintain the elements near their resonant dimensions for several frequency bands. This increases the bandwidth of the antenna dramatically, which enables the use of one antenna for several applications. Four novel reconfigurable antenna elements …

Go to article

Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua Jan 2004

Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua

Electronic Theses and Dissertations

In this thesis, the parallel barrier analysis feature in the Federal Highway Administration Traffic Noise Model (FHWA TNM), which is based on RAYVERB was used to explore the effects of multiple reflections due to single and parallel barriers and the use of absorptive treatment. Database was developed from the data collected from previous research efforts was used to generate a best fit equation model that can be used as a predetermining tool to determine the magnitude of parallel barrier insertion loss. The best fit equation model was then used to test against measured/model result and TNM prediction results for its …

Go to article

A Journey Of Teaching And Learning In Science Education: The Microculture Of Emerging Inquiry-Based Science Instruction In An Urban, Low Socioeconomic Elementary School Science Lab, Kimberly Dahl Jan 2004

A Journey Of Teaching And Learning In Science Education: The Microculture Of Emerging Inquiry-Based Science Instruction In An Urban, Low Socioeconomic Elementary School Science Lab, Kimberly Dahl

Electronic Theses and Dissertations

This ethnographic study of emerging inquiry-based science instruction in an urban, low socioeconomic elementary school science lab was designed to gain insight into the perspectives of the teacher and students. The study involved a Central Florida elementary school whose population was over 80 percent African-American. In this six month study, the researcher examined the classroom setting of a science lab teacher and her fourth and fifth grade students during a six month period of time. Data sources included interviews, field notes, reflections, and student work , which were used to identify the emerging themes and patterns in the study. The …

Go to article

Evolving Models From Observed Human Performance, Hans Karl Gustav Fernlund Jan 2004

Evolving Models From Observed Human Performance, Hans Karl Gustav Fernlund

Electronic Theses and Dissertations

To create a realistic environment, many simulations require simulated agents with human behavior patterns. Manually creating such agents with realistic behavior is often a tedious and time-consuming task. This dissertation describes a new approach that automatically builds human behavior models for simulated agents by observing human performance. The research described in this dissertation synergistically combines Context-Based Reasoning, a paradigm especially developed to model tactical human performance within simulated agents, with Genetic Programming, a machine learning algorithm to construct the behavior knowledge in accordance to the paradigm. This synergistic combination of well-documented AI methodologies has resulted in a new algorithm that …

Go to article

Electron Injection-Induced Effects In Iii-Nitrides: Physics And Applications, William Charles Burdett Jan 2004

Electron Injection-Induced Effects In Iii-Nitrides: Physics And Applications, William Charles Burdett

Electronic Theses and Dissertations

This research investigated the effect of electron injection in III-Nitrides. The combination of electron beam induced current and cathodoluminescence measurements was used to understand the impact of electron injection on the minority carrier transport and optical properties. In addition, the application of the electron injection effect in optoelectronic devices was investigated. The impact of electron injection on the minority carrier diffusion length was studied at various temperatures in Mg-doped p-GaN, p-Al[subscript x]Ga[subscript 1-x]N, and p-Al[subscript x]Ga[subscript 1-x] N/GaN superlattices. It was found that Lsubscript n] experienced a multi-fold linear increase and that the rate of change of L[subscript n] decreased …

Go to article

Interactivity And User-Heterogeneity In On Demand Broadcast Video, Mounir Tantaoui El Araki Jan 2004

Interactivity And User-Heterogeneity In On Demand Broadcast Video, Mounir Tantaoui El Araki

Electronic Theses and Dissertations

Video-On-Demand (VOD) has appeared as an important technology for many multimedia applications such as news on demand, digital libraries, home entertainment, and distance learning. In its simplest form, delivery of a video stream requires a dedicated channel for each video session. This scheme is very expensive and non-scalable. To preserve server bandwidth, many users can share a channel using multicast. Two types of multicast have been considered. In a non-periodic multicast setting, users make video requests to the server; and it serves them according to some scheduling policy. In a periodic broadcast environment, the server does not wait for service …

Go to article

Analysis And Modeling Of The Eds Maglev System Based On The Halbach Permanent Magnet Array, Qinghua Han Jan 2004

Analysis And Modeling Of The Eds Maglev System Based On The Halbach Permanent Magnet Array, Qinghua Han

Electronic Theses and Dissertations

Electro-dynamic suspension (EDS) Magnetic levitation (Maglev) with its advantage in maintenance, safety, efficiency, speed, and noise is regarded as a leading candidate for the next generation transportation / space launch assist system. The Halbach array due to its unique magnetic field feature has been widely used in various applications. The EDS system using Halbach arrays leads to the potential EDS system without super-conductor (SC) technology. In this thesis, the Halbach array magnetic field and the dynamics of a novel Halbach array EDS Maglev system were considered. The practical Halbach array magnetic field was analyzed using both a Fourier series approach …

Go to article

Mitochondrial Dna Analysis By Pyrosequencing, Patsy-Ann Susan Hastings Jan 2004

Mitochondrial Dna Analysis By Pyrosequencing, Patsy-Ann Susan Hastings

Electronic Theses and Dissertations

Mitochondrial DNA (deoxyribo nucleic acid) is typically used in forensic casework when small quantities of high molecular weight quality DNA is not expected to be present thus negating the chances of obtaining usable nuclear DNA. Typical samples that utilized mitochondrial DNA analysis are: hair, bones, teeth, ancient remains (samples or remains that are at least 100 years old) or very old samples (samples that are less than 100 but greater than 10 years old). The current method used to evaluate mitochondrial DNA is Sanger sequencing. Although robust, it is also time consuming and labor intensive, on the other hand pyrosequencing …

Go to article

Basic Study Of Micromachined Dep (Dielectrophoretic) Manipulator, Vivek Sundaram Jan 2004

Basic Study Of Micromachined Dep (Dielectrophoretic) Manipulator, Vivek Sundaram

Electronic Theses and Dissertations

The capability of manipulating microparticle in small volumes is fundamental to many biological and medical applications, including separation and detection of cells. The development of microtools for effective sample handling and separation in such volumes is still a challenge. DEP (dielectrophoresis) is one of the most widely used methods in handling the microparticles. In this thesis we show that forces generated by nonuniform electric field (DEP) can be used for trapping and separating the microparticles (latex beads). This work further explores the DEP force based on different electrode geometries and medium conductivity. A micromanipulator for latex bead separation was designed, …

Go to article

Smoothing Parameter Selection In Nonparametric Functional Estimation, Mohamed Amezziane Jan 2004

Smoothing Parameter Selection In Nonparametric Functional Estimation, Mohamed Amezziane

Electronic Theses and Dissertations

This study intends to build up new techniques for how to obtain completely data-driven choices of the smoothing parameter in functional estimation, within the confines of minimal assumptions. The focus of the study will be within the framework of the estimation of the distribution function, the density function and their multivariable extensions along with some of their functionals such as the location and the integrated squared derivatives.

Go to article

Improving Project Management With Simulation And Completion Distributi, Grant Cates Jan 2004

Improving Project Management With Simulation And Completion Distributi, Grant Cates

Electronic Theses and Dissertations

Despite the critical importance of project completion timeliness, management practices in place today remain inadequate for addressing the persistent problem of project completion tardiness. Uncertainty has been identified as a contributing factor in late projects. This uncertainty resides in activity duration estimates, unplanned upsetting events, and the potential unavailability of critical resources. This research developed a comprehensive simulation based methodology for conducting quantitative project completion-time risk assessments. The methodology enables project stakeholders to visualize uncertainty or risk, i.e. the likelihood of their project completing late and the magnitude of the lateness, by providing them with a completion time distribution function …

Go to article

Individual Carbon Nanotube Probes And Field Emitters Fabrication And T, Guangyu Chai Jan 2004

Individual Carbon Nanotube Probes And Field Emitters Fabrication And T, Guangyu Chai

Electronic Theses and Dissertations

Since the discovery of carbon nanotubes (CNT) in 1999, they have attracted much attention due to their unique mechanical and electrical properties and potential applications. Yet their nanosize makes the study of individual CNTs easier said than done. In our laboratory, carbon fibers with nanotube cores have been synthesized with conventional chemical vapor deposition (CVD) method. The single multiwall carbon nanotube (MWNT) sticks out as a tip of the carbon fiber. In order to pick up the individual CNT tips, focused ion beam (FIB) technique is applied to cut and adhere the samples. The carbon fiber with nanotube tip was …

Go to article

Effective School Characteristics And Student Achievement Correlates As, James Doran Jan 2004

Effective School Characteristics And Student Achievement Correlates As, James Doran

Electronic Theses and Dissertations

The purpose of this study is to investigate the relationships between effective school characteristics and norm referenced standardized test scores in American-style international schools. In contrast to schools in traditional effective schools research, international schools typically have middle to high SES families, and display average to above average achievement. Eleven effective school characteristics were identified and correlated with standardized test scores for grades 4, 6, and 8 and high school SAT scores. Data was gathered from an online teacher questionnaire designed for this study. All eleven characteristics were present in high performing international schools while frequent analysis of student progress, …

Go to article

Measures Of Concordance Of Polynomial Type, Heather Edwards Jan 2004

Measures Of Concordance Of Polynomial Type, Heather Edwards

Electronic Theses and Dissertations

A measure of concordance, $\kappa$, is of polynomial type if and only if $\kappa (tA+(1-t)B)$ is a polynomial in $t$ where $A$ and $B$ are 2-copulas. The degree of such a type of measure of concordance is simply the highest degree of the polynomial associated with $\kappa$. In previous work [2], [3], properties of measures of concordance preserving convex sums (equivalently measures of concordance of polynomial type degree one) were established; however, a characterization was not made. Here a characterization is made using approximations involving doubly stochastic matrices. Other representations are provided from this characterization leading naturally to two interpretations …

Go to article

Asymptotic Formulas For Large Arguments Of Hypergeometric-Type Functio, Adam Heck Jan 2004

Asymptotic Formulas For Large Arguments Of Hypergeometric-Type Functio, Adam Heck

Electronic Theses and Dissertations

Hypergeometric type functions have a long list of applications in the field of sciences. A brief history is given of Hypergeometric functions including some of their applications. A development of a new method for finding asymptotic formulas for large arguments is given. This new method is applied to Bessel functions. Results are compared with previously known methods.

Go to article

Automatic Annotation Of Database Images For Query-By-Concept, Nualsawat Hiransakolwong Jan 2004

Automatic Annotation Of Database Images For Query-By-Concept, Nualsawat Hiransakolwong

Electronic Theses and Dissertations

As digital images become ubiquitous in many applications, the need for efficient and effective retrieval techniques is more demanding than ever. Query by Example (QBE) and Query by Concept (QBC) are among the most popular query models. The former model accepts example images as queries and searches for similar ones based on low-level features such as colors and textures. The latter model allows queries to be expressed in the form of high-level semantics or concept words, such as "boat" or "car," and finds images that match the specified concepts. Recent research has focused on the connections between these two models …

Go to article

Toward Building A Social Robot With An Emotion-Based Internal Control, Andreas Marpaung Jan 2004

Toward Building A Social Robot With An Emotion-Based Internal Control, Andreas Marpaung

Electronic Theses and Dissertations

In this thesis, we aim at modeling some aspects of the functional role of emotions on an autonomous embodied agent. We begin by describing our robotic prototype, Cherry--a robot with the task of being a tour guide and an office assistant for the Computer Science Department at the University of Central Florida. Cherry did not have a formal emotion representation of internal states, but did have the ability to express emotions through her multimodal interface. The thesis presents the results of a survey we performed via our social informatics approach where we found that: (1) the idea of having emotions …

Go to article

The Effects Of The Teacher's Use Of Guided Inquiry In The Fifth Grade Classroom, Deborah Strickland Spiess Jan 2004

The Effects Of The Teacher's Use Of Guided Inquiry In The Fifth Grade Classroom, Deborah Strickland Spiess

Electronic Theses and Dissertations

THIS STUDY INVESTIGATED THE EFFECTS OF THE TEACHER'S USE OF GUIDED INQUIRY IN A FIFTH GRADE SCIENCE CLASSROOM. INQUIRY IS SUPPORTED BY THE NATIONAL RESEARCH COUNCIL(2000), AND INDICATES THAT ALL STUDENTS SHOULD DEVELOP THE ABILITIES NECESSARY TO DO SCIENTIFIC INQUIRY AND DEVELOP UNDERSTANDINGS ABOUT SCIENTIFIC INQUIRY (P.21). THIS STUDY WAS A QUALITATIVE ACTION RESEARCH DESIGN, FOCUSING ON SEVENTEEN STUDENTS AND THEIR RESPONSES TO A GUIDED INQUIRY METHOD OF SCIENCE INSTRUCTION ON MATTER, ENERGY AND MOTION, AND EARTH AND SPACE. AN ANALYSIS OF STUDENTS' PERFORMANCE AND STUDENTS' ATTITUDES ABOUT SCIENCE IN THE CLASSROOM WAS CONDUCTED ABOUT EACH UNIT OF INSTRUCTION. THE …

Go to article

First Prev Next Last