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Design Of A Dynamic Focusing Microscope Objective For Oct Imaging, Supraja Murali Jan 2005

Design Of A Dynamic Focusing Microscope Objective For Oct Imaging, Supraja Murali

Electronic Theses and Dissertations

Optical Coherence Tomography (OCT) is a novel optical imaging technique that has assumed significant importance in bio-medical imaging in the last two decades because it is non-invasive and provides accurate, high resolution images of three dimensional cross-sections of body tissue, exceeding the capabilities of the current predominant imaging technique –ultrasound. In this thesis, high resolution OCT is investigated for in vivo detection of abnormal skin pathology for the early diagnosis of cancer. The technology presented is based on a dynamic focusing microscopic imaging probe conceived for skin imaging and the detection of abnormalities in the epithelium. A novel method for …

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Fraction Models That Promote Understanding For Elementary Students, Lynette Hull Jan 2005

Fraction Models That Promote Understanding For Elementary Students, Lynette Hull

Electronic Theses and Dissertations

This study examined the use of the set, area, and linear models of fraction representation to enhance elementary students' conceptual understanding of fractions. Students' preferences regarding the set, area, and linear models of fractions during independent work was also investigated. This study took place in a 5th grade class consisting of 21 students in a suburban public elementary school. Students participated in classroom activities which required them to use manipulatives to represent fractions using the set, area, and linear models. Students also had experiences using the models to investigate equivalent fractions, compare fractions, and perform operations. Students maintained journals throughout …

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The Effect Of Pre-K Early Intervention Duration On Academic Achievement And Socialization Opportunities Of 3rd Grade Students Who Were Eligible For Special Education Services At Ages 3 To 5: An Exploratory Study Of Children With Developmental Delays, Mike Chang-Hui Lin Jan 2005

The Effect Of Pre-K Early Intervention Duration On Academic Achievement And Socialization Opportunities Of 3rd Grade Students Who Were Eligible For Special Education Services At Ages 3 To 5: An Exploratory Study Of Children With Developmental Delays, Mike Chang-Hui Lin

Electronic Theses and Dissertations

The study focuses on young children with developmental delays (DD) in a large school district and explores the effects of Pre-Kindergarten Exceptional Student Education (Pre-K ESE) duration on 136 students' 3rd grade academic achievement and socialization opportunities. This study specifically examines the 2003 statewide assessment (i.e. Florida Comprehensive Assessment Test, FCAT) results of children with DD and their 3rd grade special education status. The literature review showed that providing early intervention services for young children ages 3 through 5 with special needs in the public school system has become the movement of both the federal and state educational policies. However, …

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Refractive Indices Of Liquid Crystals And Their Applications In Display And Photonic Devices, Jun Li Jan 2005

Refractive Indices Of Liquid Crystals And Their Applications In Display And Photonic Devices, Jun Li

Electronic Theses and Dissertations

Liquid crystals (LCs) are important materials for flat panel display and photonic devices. Most LC devices use electrical field-, magnetic field-, or temperature-induced refractive index change to modulate the incident light. Molecular constituents, wavelength, and temperature are the three primary factors determining the liquid crystal refractive indices: ne and no for the extraordinary and ordinary rays, respectively. In this dissertation, we derive several physical models for describing the wavelength and temperature effects on liquid crystal refractive indices, average refractive index, and birefringence. Based on these models, we develop some high temperature gradient refractive index LC mixtures for photonic applications, such …

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Parameter Estimates For Fractional Autoregressive Spatial Processes, Y. Boissy, B. B. Bhattacharyya, X. Li, G. D. Richardson Jan 2005

Parameter Estimates For Fractional Autoregressive Spatial Processes, Y. Boissy, B. B. Bhattacharyya, X. Li, G. D. Richardson

Faculty Bibliography 2000s

A binomial-type operator on a stationary Gaussian process is introduced in order to model long memory in the spatial context. Consistent estimators of model parameters are demonstrated. In particular, it is shown that (d) over cap (N) - d = Op((Log N)3)/(N)), where d = (d(1), d(2)) denotes the long memory parameter.

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Wave Dynamics In Optically Modulated Waveguide Arrays, Mark J. Ablowitz, Keith Julien, Ziad H. Musslimani, Michael I. Weinstein Jan 2005

Wave Dynamics In Optically Modulated Waveguide Arrays, Mark J. Ablowitz, Keith Julien, Ziad H. Musslimani, Michael I. Weinstein

Faculty Bibliography 2000s

A model describing wave propagation in optically modulated waveguide arrays is proposed. In the weakly guided regime, a two-dimensional semidiscrete nonlinear Schrodinger equation with the addition of a bulk diffraction term and an external "optical trap" is derived from first principles, i.e., Maxwell equations. When the nonlinearity is of the defocusing type, a family of unstaggered localized modes are numerically constructed. It is shown that the equation with an induced potential is well-posed and gives rise to localized dynamically stable nonlinear modes. The derived model is of the Gross-Pitaevskii type, a nonlinear Schrodinger equation with a linear optical potential, which …

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Efficient Estimation Of A Semiparametric Partially Linear Varying Coefficient Model, Ibrahim Ahmad, Sittisak Leelahanon, Qi Li Jan 2005

Efficient Estimation Of A Semiparametric Partially Linear Varying Coefficient Model, Ibrahim Ahmad, Sittisak Leelahanon, Qi Li

Faculty Bibliography 2000s

In this paper we propose a general series method to estimate a semiparametric partially linear varying coefficient model. We establish the consistency and root n-normality property of the estimator of the finite-dimensional parameters of the model, We further show that, when the error is conditionally homoskedastic. this estimator is semiparametrically efficient in the sense that the inverse of the asymptotic variance of the estimator of the finite-dimensional parameter reaches the semiparametric efficiency bound of this model. A small-scale simulation is reported to examine the finite.sample performance of the proposed estimator, and an empirical application is presented to illustrate the usefulness …

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Non-Gaussian Statistics Of Optical Near-Fields, A. Apostol, A. Dogariu Jan 2005

Non-Gaussian Statistics Of Optical Near-Fields, A. Apostol, A. Dogariu

Faculty Bibliography 2000s

Optical fields in the proximity of random media can be modeled as a superposition of waves with random phases. We demonstrate that, depending on the experimental geometry, both Gaussian and non-Gaussian regimes can be established for the statistics of scattered intensity. In a reflection-emission configuration, the first-order statistics of the scattered light is non-Gaussian and it can be used to retrieve information about the physical interface.

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Optoelectronically Automated System For Carbon Nanotubes Synthesis Via Arc-Discharge In Solution, Debasis Bera, Erik Brinley, Suresh C. Kuiry, Matthew Mccutchen, Sudipta Seal, Helge Heinrich, Bradley Kabes Jan 2005

Optoelectronically Automated System For Carbon Nanotubes Synthesis Via Arc-Discharge In Solution, Debasis Bera, Erik Brinley, Suresh C. Kuiry, Matthew Mccutchen, Sudipta Seal, Helge Heinrich, Bradley Kabes

Faculty Bibliography 2000s

The method of arc discharge in the solution is unique and inexpensive route for synthesis of the carbon nanotubes (CNTs), carbon onions, and other carbon nanostructures. Such a method can be used for in situ synthesis of CNTs decorated with nanoparticles. Herein, we report a simple and inexpensive optoelectronically automated system for arc discharge in solution synthesis of CNTs. The optoelectronic system maintains a constant gap between the two electrodes allowing a continuous synthesis of the carbon nanostructures. The system operates in a feedback loop consisting of an electrode-gap detector and an analog electronic unit, as controller. This computerized feeding …

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Noise Statistics Of And Ber Estimation Using Demodulated Signals For Direct Detection Differential Polarization-Phase-Shift Keying, Yan Han, Guifang Li Jan 2005

Noise Statistics Of And Ber Estimation Using Demodulated Signals For Direct Detection Differential Polarization-Phase-Shift Keying, Yan Han, Guifang Li

Faculty Bibliography 2000s

The noise statistics of optically demodulated signal of the recently proposed modulation format, namely differential polarization-phase-shift keying, are analyzed. It is found that, in the linear regime, the Gaussian approximation is reasonably accurate in estimating the BER. In the nonlinear regime, the noise of the demodulated signal is dominated by the effect of nonlinear phase noise and obeys chi-squared statistics with a degree of freedom of one. Gaussian approximation underestimates the BER in the nonlinear regime. A two-step BER estimation method accounting for both linear beat noise and nonlinear phase noise is proposed. The effectiveness of this two-step BER estimation …

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Predicting Rogue Waves In Random Oceanic Sea States, A. L. Islas, C. M. Schober Jan 2005

Predicting Rogue Waves In Random Oceanic Sea States, A. L. Islas, C. M. Schober

Faculty Bibliography 2000s

Using the inverse spectral theory of the nonlinear Schrodinger (NLS) equation we correlate the development of rogue waves in oceanic sea states characterized by the Joint North Sea Wave Project (JONSWAP) spectrum with the proximity to homoclinic solutions of the NLS equation. We find in numerical simulations of the NLS equation that rogue waves develop for JONSWAP initial data that are "near" NLS homoclinic data, while rogue waves do not occur for JONSWAP data that are "far" from NLS homoclinic data. We show the nonlinear spectral decomposition provides a simple criterium for predicting the occurrence and strength of rogue waves.

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Sequence Dependence Of Cross-Hybridization On Short Oligo Microarrays, Chunlei Wu, Roberto Carta, Li Zhang Jan 2005

Sequence Dependence Of Cross-Hybridization On Short Oligo Microarrays, Chunlei Wu, Roberto Carta, Li Zhang

Faculty Bibliography 2000s

One of the critical problems in the short oligo microarray technology is how to deal with cross-hybridization that produces spurious data. Little is known about the details of cross-hybridization effect at molecular level. Here, we report a free energy analysis of crosshybridization on short oligo microarrays using data from a spike-in study. Our analysis revealed that cross-hybridization on the arrays is mostly caused by oligo fragments with a run of 10 - 16 nt complementary to the probes. Mismatches were estimated to be energetically much more costly in crosshybridization than that in gene-specific hybridization, implying that the sources of cross-hybridization …

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Two-Dimensional Model For Melting And Vaporization During Optical Trepanning, D. Zeng, W. P. Latham, A. Kar Jan 2005

Two-Dimensional Model For Melting And Vaporization During Optical Trepanning, D. Zeng, W. P. Latham, A. Kar

Faculty Bibliography 2000s

Annular laser beams provide a drilling mechanism that can be referred to as optical trepanning. In this paper an analytical two-dimensional model is developed for optical trepanning. The analysis accounts for conduction in the solid, vaporization, and convection due to the melt flow caused by an assist gas. Based on the model, the influences of pulse duration, laser-pulse length, pulse repetition rate, intensity profiles, and beam radius are investigated to examine their effects on the recast layer thickness, hole depth, and taper. Deeper cavity depth, thicker recast layer, and larger taper are obtained with the increase in the laser intensity. …

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Generalized Optical Theorem For Reflection, Transmission, And Extinction Of Power For Electromagnetic Fields, D. R. Lytle Ii, P. Scott Carney, John C. Schotland, Emil Wolf Jan 2005

Generalized Optical Theorem For Reflection, Transmission, And Extinction Of Power For Electromagnetic Fields, D. R. Lytle Ii, P. Scott Carney, John C. Schotland, Emil Wolf

Faculty Bibliography 2000s

We present a generalization of the optical theorem for electromagnetic fields. This result is used to obtain the power extinguished from a field by a scatterer contained in a dielectric half space. Applications to microscopy and tomography are described.

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Nonlinear Fano Resonance And Bistable Wave Transmission, Andrey E. Miroshnichenko, Sergei F. Mingaleev, Sergej Flach, Yuri S. Kivshar Jan 2005

Nonlinear Fano Resonance And Bistable Wave Transmission, Andrey E. Miroshnichenko, Sergei F. Mingaleev, Sergej Flach, Yuri S. Kivshar

Faculty Bibliography 2000s

We consider a discrete model that describes a linear chain of particles coupled to a single-site defect with instantaneous Kerr nonlinearity. We show that this model can be regarded as a nonlinear generalization of the familiar Fano-Anderson model and it can generate amplitude-dependent bistable resonant transmission or reflection. We identify these effects as the nonlinear Fano resonance and study its properties for continuous waves and pulses.

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Polar Anchoring Energy Measurement Of Vertically Aligned Liquid-Crystal Cells, Xiangyi Nie, Yi-Hsin Lin, Thomas X. Wu, Haiying Wang, Zhibing Ge, Shin-Tson Wu Jan 2005

Polar Anchoring Energy Measurement Of Vertically Aligned Liquid-Crystal Cells, Xiangyi Nie, Yi-Hsin Lin, Thomas X. Wu, Haiying Wang, Zhibing Ge, Shin-Tson Wu

Faculty Bibliography 2000s

An electric-field method is developed for measuring the polar anchoring energy of vertically aligned nematic liquid-crystal cells. Both theoretical analyses and confirming experimental results are presented. Vertically aligned liquid-crystal cells with buffed polyimide alignment layers are used to investigate the measurement techniques. Based on the voltage-dependent transmittance of the liquid-crystal cells, a linear fitting can be obtained, leading to a precise determination of the anchoring energy. If some specific liquid-crystal material parameters are known, measuring of the cell capacitance is not necessary.

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Numerical Model Of The Temperature Dependence Of The Up-Conversion Efficiency Of Fluoride Crystals Codoped With Ytterbium And Thulium, A. Rapaport, J. Milliez, M. Bass, A. Cassanho, H. Jenssen Jan 2005

Numerical Model Of The Temperature Dependence Of The Up-Conversion Efficiency Of Fluoride Crystals Codoped With Ytterbium And Thulium, A. Rapaport, J. Milliez, M. Bass, A. Cassanho, H. Jenssen

Faculty Bibliography 2000s

We review the role of temperature on the up-conversion efficiency of materials that are good candidates to be used as the three primary-color emitters in optically written displays. A rate equation model is given for the blue emitting material that includes temperature-dependent coefficients for energy transfer and cross relaxation. Increased temperature leads to decreased up-conversion efficiency. The effect of pumping conditions on heating the emitting material is illustrated and explained. Steps to reduce the temperature rise when pumping up-conversion materials are described.

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Analytical Expression For The Output Voltage Of The Triple Resonance Tesla Transformer, John Randolph Reed Jan 2005

Analytical Expression For The Output Voltage Of The Triple Resonance Tesla Transformer, John Randolph Reed

Faculty Bibliography 2000s

An analytical expression for the time-dependent output voltage of the triple resonance Tesla transformer is presented. Presently there does not exist any closed-form solution for the output voltage, and the investigators must use circuit simulators to examine the transformer's performance. Such simulators are satisfactory in many regards, but they cannot furnish physical insight into the triple resonance device. A governing equation provides this needed insight and opens the way for obtaining optimal high-performance transformers. The present analysis treats the transformer as three oscillatory LC tank circuits feeding a load capacitance. The circuit is assumed to have a very high Q, …

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Development Of Head-Mounted Projection Displays For Distributed, Collaborative, Augmented Reality Applications, Jannick P. Rolland, Frank Biocca, Felix Hamza-Lup, Yanggang Ha Jan 2005

Development Of Head-Mounted Projection Displays For Distributed, Collaborative, Augmented Reality Applications, Jannick P. Rolland, Frank Biocca, Felix Hamza-Lup, Yanggang Ha

Faculty Bibliography 2000s

Distributed systems technologies supporting 3D visualization and social collaboration will be increasing in frequency and type over time. An emerging type of head-mounted display referred to as the head-mounted projection display (HMPD) was recently developed that only requires ultralight optics (i.e., less than 8 g per eye) that enables immersive multiuser, mobile augmented reality 3D visualization, as well as remote 3D collaborations. In this paper a review of the development of lightweight HMPD technology is provided, together with insight into what makes this technology timely and so unique. Two novel emerging HMPD-based technologies are then described: a teleportal WED (T-HMPD) …

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Comprehensive Modeling Of Near-Field Nano-Patterning, Raymond C. Rumpf, Eric G. Johnson Jan 2005

Comprehensive Modeling Of Near-Field Nano-Patterning, Raymond C. Rumpf, Eric G. Johnson

Faculty Bibliography 2000s

Near-field nano-patterning greatly simplifies holographic lithography, but deformations in formed structures are potentially severe. A fast and efficient comprehensive model was developed to predict geometry more rigorously. Numerical results show simple intensity-threshold methods do not accurately predict shape or optical behavior. By modeling sources with partial coherence, unpolarized light, and an angular spectrum, it is shown that standard UV lamps can be used to form 3D structures.

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Symmetries Of Second Order Potential Differential Systems, Celestin Wafo Soh, Constantin Udriste Jan 2005

Symmetries Of Second Order Potential Differential Systems, Celestin Wafo Soh, Constantin Udriste

Faculty Bibliography 2000s

We characterize the family of second order potential differential systems, with n degrees of freedom, via their symmetries. Firstly, we calculate explicitly the equivalence Lie algebra and the weal, equivalence Lie algebra. It is shown that the equivalence Lie algebra has the dimension n + 4 + n(n - 1)/2 whereas the weak equivalence Lie algebra is infinite-2 dimensional. The later contains strictly the former. Secondly, we investigate the Lie-point symmetry structure. We start with a quadratic potential, and we provide an analysis relying on the spectral theorem. In the case of non-quadratic potentials, we establish the conditions for the …

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Discrete Wave Propagation In Quadratically Nonlinear Media, Robert Iwanow Jan 2005

Discrete Wave Propagation In Quadratically Nonlinear Media, Robert Iwanow

Electronic Theses and Dissertations

Discrete models are used in describing various microscopic phenomena in many branches of science, ranging from biology through chemistry to physics. Arrays of evanescently coupled, equally spaced, identical waveguides are prime examples of optical structures in which discrete dynamics can be easily observed and investigated. As a result of discretization, these structures exhibit unique diffraction properties with no analogy in continuous systems. Recently nonlinear discrete optics has attracted a growing interest, triggered by the observation of discrete solitons in AlGaAs waveguide arrays reported by Eisenberg et al. in 1998. So far, the following experiments involved systems with third order nonlinearities. …

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Deriving The Density Of States For Granular Contact Forces, Philip Metzger Jan 2005

Deriving The Density Of States For Granular Contact Forces, Philip Metzger

Electronic Theses and Dissertations

The density of single grain states in static granular packings is derived from first principles for an idealized yet fundamental case. This produces the distribution of contact forces P_f(f) in the packing. Because there has been some controversy in the published literature over the exact form of the distribution, this dissertation begins by reviewing the existing empirical observations to resolve those controversies. A method is then developed to analyze Edwards' granular contact force probability functional from first principles. The derivation assumes Edwards' flat measure -- a density of states (DOS) that is uniform within the metastable regions of phase space. …

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Relationships Among School Counselor Self-Efficacy, Perceived School Counselor Role, And Actual Practice, Michelle Mitcham-Smith Jan 2005

Relationships Among School Counselor Self-Efficacy, Perceived School Counselor Role, And Actual Practice, Michelle Mitcham-Smith

Electronic Theses and Dissertations

The purpose of this study was to investigate the relationships that exist among school counselor self-efficacy, perceptions of the professional school counselor's role held by counselors, and actual practice. Data were collected from 192 professional school counselors that attended a statewide counselor conference. Professional school counselors responded to two researcher-designed surveys; the first was a 14-item demographic survey; the second, a 20-item by four-question survey for a total of 80 responses. A Multiple Regression Analysis was used to ascertain what relationships existed between school counselor self-efficacy, school counselor perceived role, and actual practice. The questionnaire listed 20 different counselor and …

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Utilization Of Total Mass As A Control In Diffusion Processes, Mohamed Salman Jan 2005

Utilization Of Total Mass As A Control In Diffusion Processes, Mohamed Salman

Electronic Theses and Dissertations

As motivation for the mathematical problems considered in this work, consider a chamber in the form of a long linear transparent tube. We allow for the introduction or removal of material in a gaseous state at the ends of the tube. The material diffuses throughout the tube with or without reaction with other materials. By illuminating the tube on one side with a light source with a frequency range spanning the absorption range for the material and collecting the residual light that passes through the tube with photo-reception equipment, we can obtain a measurement of the total mass of material …

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A Measure Of Entrepreneurial Risk Preference And Optimism Using Field Experiments, Mark Schneider Jan 2005

A Measure Of Entrepreneurial Risk Preference And Optimism Using Field Experiments, Mark Schneider

Electronic Theses and Dissertations

Previous studies have underscored the economic importance of the role of the entrepreneur, and empirical studies testing the nature of the entrepreneur are notably lacking. This study directly addresses this issue by examining newly gathered field data which captures the decision making and risk behaviors for a group of high-technology entrepreneurs. Two decision making tasks were used to elicit risk aversion measures and to test for any 'joy of winning' or judgmental errors, possibly in the form of over optimistic behavior. These elicitations were made with the use of multiple price formats and winner's curse experiments. 62 responses were collected …

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Students With Either Specific Learning Disabilities Or With Attention Deficit Hyperactivity Disorder: Perceptions Of Self As Learner In Online Courses At Florida Virtual School And In The Traditional Learning Environment, Theresa Smouse Jan 2005

Students With Either Specific Learning Disabilities Or With Attention Deficit Hyperactivity Disorder: Perceptions Of Self As Learner In Online Courses At Florida Virtual School And In The Traditional Learning Environment, Theresa Smouse

Electronic Theses and Dissertations

The goal of this research study was to investigate the perception of self as learner for students with Specific Learning Disabilities (SLD) or with Attention Deficit Hyperactivity Disorder (ADHD). Students who had completed at least one mathematics or science course at Florida Virtual School, an online learning environment, were surveyed concerning their perception of self as learner in the online learning environment and in the traditional learning environment in 6 basic areas: feelings of success; level of comfort; relationship with teachers; and access to, communication with and feedback from teachers; and advantages and disadvantages of each learning environment. Results of …

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An Investigation Of Implementations Of Smaller Learning Communities In Florida High Schools, Todd James Bondurant Sparger Jan 2005

An Investigation Of Implementations Of Smaller Learning Communities In Florida High Schools, Todd James Bondurant Sparger

Electronic Theses and Dissertations

The issue of high school reform has received national attention during the first part of the 21st century. One idea brought forth in this restructuring effort has been the desire to create high schools with smaller student populations. However, in an era of tight budgets, where resources are not always available to build more schools, educators have explored the possibility of dividing existing large high schools into smaller units. This restructuring approach has many titles, but is frequently referred to as a Smaller Learning Community (SLC). Since 2000, the federal government has pledged $245 million to schools willing to create …

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Compressed Pattern Matching For Text And Images, Tao Tao Jan 2005

Compressed Pattern Matching For Text And Images, Tao Tao

Electronic Theses and Dissertations

The amount of information that we are dealing with today is being generated at an ever-increasing rate. On one hand, data compression is needed to efficiently store, organize the data and transport the data over the limited-bandwidth network. On the other hand, efficient information retrieval is needed to speedily find the relevant information from this huge mass of data using available resources. The compressed pattern matching problem can be stated as: given the compressed format of a text or an image and a pattern string or a pattern image, report the occurrence(s) of the pattern in the text or image …

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Effects Of A Mathematics Curriculum Rich In Spatial Reasoning Activities On Fifth Grade Students' Abilities To Spatially Reason: An Action Research Project, Theresa Varn Jan 2005

Effects Of A Mathematics Curriculum Rich In Spatial Reasoning Activities On Fifth Grade Students' Abilities To Spatially Reason: An Action Research Project, Theresa Varn

Electronic Theses and Dissertations

The purpose of this study is to describe the effect of a curriculum rich in spatial reasoning activities and experiences on the ability of my fifth grade students to spatially reason. The study was conducted to examine 1) the effects of my practice of incorporating spatial reasoning lessons and activities in my fifth-grade mathematics classroom on the students' ability to spatially reason and 2) the effects of my practice of incorporating spatial reasoning lessons and activities on my students' ability to problem solve. Data were collected over a ten-week period through the use of student interviews, anecdotal records, photos of …

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