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Probabilistic Model And Algorithms Design For Motif Detection, Yuan Xue Aug 2013

Probabilistic Model And Algorithms Design For Motif Detection, Yuan Xue

Theses and Dissertations - UTB/UTPA

In this thesis, a natural probabilistic model has been used to test the quality of motif discovery programs. In this model, there are k background sequences, in which each character is a random character from Σ. Motif is a string G = g1g2 . . . gm. Each background sequence is implanted a probabilistically generated approximate copy of G. For each copy b1b2 . . . bm of G, every character bi is probabilistically generated such that the probability for bi 6= gi is at most α. Based on this model, two randomized algorithms ,one deterministic algorithm and one enumerative …

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Dynamical Behaviors Of Gonorrhea Strain Competition Model, Marisabel Rodriguez Aug 2013

Dynamical Behaviors Of Gonorrhea Strain Competition Model, Marisabel Rodriguez

Theses and Dissertations - UTB/UTPA

In the past decades, Gonorrhea, a sexually transmitted bacterial infection caused by Neisseria gonorrhoeae, has become resistant to a wider range of antibiotics. We apply a phenomenological model that takes into account essential ideas such as the effects of different treatment levels, the transformation and conjugation rates of bacteria, and the response of the immune system. Qualitative analysis provides a more integral view of how model parameters affect the emergence of within-host resistance.

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Nonlinear Dynamics Of Carbon Nanotubes Under Soft Alternating Current Actuation, Le Luo Aug 2013

Nonlinear Dynamics Of Carbon Nanotubes Under Soft Alternating Current Actuation, Le Luo

Theses and Dissertations - UTB/UTPA

This thesis work deals with electrostatically actuated Carbon Nanotubes (CNTs) cantilevers. Four forces are acting on the CNTs cantilever, namely damping, elastic, electrostatic and van der Waals forces. The van der Waals force is significant for values of 50 nm or lower of the gap between the CNTs and the ground substrate. As both electrostatic and van der Waals forces are nonlinear, and the CNTs electrostatic actuation is given by alternating current (AC) voltage, the CNTs undergo nonlinear parametric dynamics. The Method of Multiple Scales (MMS) and Reduced Order Model (ROM) are employed to investigate the system under soft excitation …

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Algorithms In Abstract Dna Self Assembly, Xingsi Zhong Aug 2013

Algorithms In Abstract Dna Self Assembly, Xingsi Zhong

Theses and Dissertations - UTB/UTPA

For the past two years, I have always been working on the topic of Abstract DNA Tiles Self-Assembly. This is a very new area, driven by the interest of DNA molecules. The feature that the system composed by DNA molecules can be a highly parallelized system, make it much more powerful when comparing with the traditional methods. This thesis will introduce the concept of abstract DNA self-assembly models as well as some interesting problems and their solutions.

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Innovation-Ict-Cybersecurity: The Triad Relationship And Its Impact On Growth Competitiveness, Manal M. Yunis Aug 2013

Innovation-Ict-Cybersecurity: The Triad Relationship And Its Impact On Growth Competitiveness, Manal M. Yunis

Theses and Dissertations - UTB/UTPA

This study examines the global growth competitiveness of countries using the dynamics of growth, ICT, and innovation. It also introduces a new dynamic, cybersecurity, and argues that within a growth competitiveness framework, ICT, innovation, and cybersecurity mechanisms allow some countries to achieve higher ranks on the competitiveness ladder than others. Based on a theoretical framework that encompasses the economic growth model, the complementarity theory, and the international law theory, a model that integrates ICT, innovation, and cybersecurity, depicts the relationships amongst them and with growth competitiveness, and incorporates complementary factors with possible moderating effect is presented. The model proposed relationships …

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Timing And Interstellar Scattering Of 35 Distant Pulsars Discovered In The Palfa Survey, D. J. Nice, E. Altiere, S. Bogdanov, J. M. Cordes, D. Farrington, J. W.T. Hessels, V. M. Kaspi, A. G. Lyne, Fredrick A. Jenet, Kevin Stovall Jul 2013

Timing And Interstellar Scattering Of 35 Distant Pulsars Discovered In The Palfa Survey, D. J. Nice, E. Altiere, S. Bogdanov, J. M. Cordes, D. Farrington, J. W.T. Hessels, V. M. Kaspi, A. G. Lyne, Fredrick A. Jenet, Kevin Stovall

Physics & Astronomy Faculty Publications

We have made extensive observations of 35 distant slow (non-recycled) pulsars discovered in the ongoing Arecibo PALFA pulsar survey. Timing observations of these pulsars over several years at Arecibo Observatory and Jodrell Bank Observatory have yielded high-precision positions and measurements of rotation properties. Despite being a relatively distant population, these pulsars have properties that mirror those of the previously known pulsar population. Many of the sources exhibit timing noise, and one underwent a small glitch. We have used multifrequency data to measure the interstellar scattering properties of these pulsars. We find scattering to be higher than predicted along some lines …

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A Lover And A Fighter: The Genome Sequence Of An Entomopathogenic Nematode Heterorhabditis Bacteriophora, Xiaodong Bai, Byron J. Adams, Todd A. Ciche, Sandra Clifton, Randy Gaugler, Kwi-Suk Kim, Parwinder Grewal Jul 2013

A Lover And A Fighter: The Genome Sequence Of An Entomopathogenic Nematode Heterorhabditis Bacteriophora, Xiaodong Bai, Byron J. Adams, Todd A. Ciche, Sandra Clifton, Randy Gaugler, Kwi-Suk Kim, Parwinder Grewal

School of Earth, Environmental, & Marine Sciences Faculty Publications

Heterorhabditis bacteriophora are entomopathogenic nematodes that have evolved a mutualism with Photorhabdus luminescens bacteria to function as highly virulent insect pathogens. The nematode provides a safe harbor for intestinal symbionts in soil and delivers the symbiotic bacteria into the insect blood. The symbiont provides virulence and toxins, metabolites essential for nematode reproduction, and antibiotic preservation of the insect cadaver. Approximately half of the 21,250 putative protein coding genes identified in the 77 Mbp high quality draft H. bacteriophora genome sequence were novel proteins of unknown function lacking homologs in Caenorhabditis elegans or any other sequenced organisms. Similarly, 317 of the …

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Project South Texas Guiding Principles Jul 2013

Project South Texas Guiding Principles

Project South Texas

No abstract provided.

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Resisting And Reimagining: Flores, Ayguals, And 19th-Century Technological Innovation, Catherine Sundt Jul 2013

Resisting And Reimagining: Flores, Ayguals, And 19th-Century Technological Innovation, Catherine Sundt

Hipertexto

No abstract provided.

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From Prescription To Possibility: Becoming A Writer In J.M. Coetzee’S "Youth", Craig Smith Jul 2013

From Prescription To Possibility: Becoming A Writer In J.M. Coetzee’S "Youth", Craig Smith

Journal of South Texas English Studies

No abstract provided.

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Utpa Commencement – Summer 2013, University Of Texas-Pan American Jul 2013

Utpa Commencement – Summer 2013, University Of Texas-Pan American

Edinburg Archives - Legacy Commencement Programs

No abstract provided.

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Uso De Hábitat Y Perspectivas De Lontra Longicaudis En Un Área Protegida De Tamaulipas, México, Piedad Esther Mayagoitia-González, Alejandro Fierro-Cabo, Raul Valdez, Mark Andersen, David Cowley, Robert Steiner Jul 2013

Uso De Hábitat Y Perspectivas De Lontra Longicaudis En Un Área Protegida De Tamaulipas, México, Piedad Esther Mayagoitia-González, Alejandro Fierro-Cabo, Raul Valdez, Mark Andersen, David Cowley, Robert Steiner

School of Earth, Environmental, & Marine Sciences Faculty Publications

El hábitat de la nutria neotropical (Lontra longicaudis) en el Área Natural Protegida (ANP) La Vega Escondida, ubicada al sur de Tamaulipas, se encuentra rodeado de un paisaje urbano en expansión. Los humedales en esta región están sometidos a una intensa presión debido a diversas actividades antropogénicas tales como la agricultura, ganadería y pesca comercial, así como construcciones y rellenos en orillas de laguna y río. El presente estudio tuvo como objetivos principales la evaluación y uso de hábitat de la nutria dentro del ANP La Vega Escondida, así como determinar la actitud de la población humana hacia esta especie. …

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Peace: Pulsar Evaluation Algorithm For Candidate Extraction-A Software Package For Post-Analysis Processing Of Pulsar Survey Candidates, K. J. Lee, Kevin Stovall, Fredrick Jenet, Jose Guadalupe Martinez, Louis Percy Dartez, Alberto Mata, Grady Lunsford, Stephanie Cohen, C. M. Biwer, M. Rohr Jul 2013

Peace: Pulsar Evaluation Algorithm For Candidate Extraction-A Software Package For Post-Analysis Processing Of Pulsar Survey Candidates, K. J. Lee, Kevin Stovall, Fredrick Jenet, Jose Guadalupe Martinez, Louis Percy Dartez, Alberto Mata, Grady Lunsford, Stephanie Cohen, C. M. Biwer, M. Rohr

Physics & Astronomy Faculty Publications

Modern radio pulsar surveys produce a large volume of prospective candidates, the majority of which are polluted by human-created radio frequency interference or other forms of noise. Typically, large numbers of candidates need to be visually inspected in order to determine if they are real pulsars. This process can be labour intensive. In this paper, we introduce an algorithm called Pulsar Evaluation Algorithm for Candidate Extraction (peace) which improves the efficiency of identifying pulsar signals. The algorithm ranks the candidates based on a score function. Unlike popular machine-learning-based algorithms, no prior training data sets are required. This algorithm has been …

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Study Of The Thermodynamics Of Chromium(Iii) And Chromium(Vi) Binding To Iron(Ii/Iii)Oxide Or Magnetite Or Ferrite And Magnanese(Ii) Iron (Iii) Oxide Or Jacobsite Or Manganese Ferrite Nanoparticles, Steven Luther, Nathan Brogfeld, Jisoo Kim, Jason Parsons Jun 2013

Study Of The Thermodynamics Of Chromium(Iii) And Chromium(Vi) Binding To Iron(Ii/Iii)Oxide Or Magnetite Or Ferrite And Magnanese(Ii) Iron (Iii) Oxide Or Jacobsite Or Manganese Ferrite Nanoparticles, Steven Luther, Nathan Brogfeld, Jisoo Kim, Jason Parsons

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Removal of chromium(III) or (VI) from aqueous solution was achieved using Fe3O4, and MnFe2O4 nanomaterials. The nanomaterials were synthesized using a precipitation method and characterized using XRD. The size of the nanomaterials was determined to be 22.4±0.9 nm (Fe3O4) and 15.5±0.5 nm (MnFe2O4). The optimal binding pH for chromium(III) and chromium(VI) were pH 6 and pH 3. Isotherm studies were performed, under light and dark conditions, to determine the capacity of the nanomaterials. The capacities for the light studies with MnFe2O4 and Fe3O4 were determined to be 7.189 and 10.63 mg/g, respectively, for chromium(III). The capacities for the light studies …

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The Pan American (2013-06-06), Norma Gonzalez, Lea Victoria Juarez Jun 2013

The Pan American (2013-06-06), Norma Gonzalez, Lea Victoria Juarez

UTPA Archives - The Pan American Newspaper

Vol. 69, No. 27

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Observation Of Asymmetric Transport In Structures With Active Nonlinearities, N. Bender, S. Factor, J. D. Bodyfelt, Hamidreza Ramezani, D. N. Christodoulides, F. M. Ellis, T. Kottos Jun 2013

Observation Of Asymmetric Transport In Structures With Active Nonlinearities, N. Bender, S. Factor, J. D. Bodyfelt, Hamidreza Ramezani, D. N. Christodoulides, F. M. Ellis, T. Kottos

Physics & Astronomy Faculty Publications

A mechanism for asymmetric transport which is based on parity-time- symmetric nonlinearities is presented. We show that in contrast to the case of conservative nonlinearities, an increase of the complementary conductance strength leads to a simultaneous increase of asymmetry and transmittance intensity. We experimentally demonstrate the phenomenon using a pair of coupled Van der Pol oscillators as a reference system, each with complementary anharmonic gain and loss conductances, connected to transmission lines. An equivalent optical setup is also proposed. © 2013 American Physical Society.

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El Poder De La Tutoría En Pares Bilingües Durante La Enseñanza De Ciencia: Diseñando Oportunidades Para Explicar, María G. Arreguín-Anderson, Zulmaris Diaz, Jose A. Ruiz-Escalante Jun 2013

El Poder De La Tutoría En Pares Bilingües Durante La Enseñanza De Ciencia: Diseñando Oportunidades Para Explicar, María G. Arreguín-Anderson, Zulmaris Diaz, Jose A. Ruiz-Escalante

Bilingual and Literacy Studies Faculty Publications

En este artículo se propone la utilización de la tutoría en pares como estrategia para facilitar la elaboración de explicaciones mientras se aprende la ciencia. Los autores argumentan que, sistemáticamente incluida dentro de la instrucción, la tutoría en pares permite que un estudiante con mayor dominio de la materia auxilie a un compañero en el aprendizaje de la ciencia al mismo tiempo que ambos se involucran en la práctica de todas las destrezas del lenguaje. A manera de ilustración, los autores narran cómo una lección de ciencias naturales se enriqueció con dos estrategias de tutoría: parejas de discusión guiada y …

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Hydro-Thermal Convective Solutions For An Aquifer System Heated From Below, Dambaru Bhatta Jun 2013

Hydro-Thermal Convective Solutions For An Aquifer System Heated From Below, Dambaru Bhatta

School of Mathematical & Statistical Sciences Faculty Publications

We investigate the effect of hydro-thermal convection in an aquifer system. It is assumed that the aquifer is bounded below and above by impermeable boundaries and it is heated from below. The solution of the governing system is expressed in terms of the basic steady state solution and perturbed solution. We obtain the critical Rayleigh number and critical wavenumber using Runge-Kutta method in combination of shooting method and present the marginal stability curve. The amplitude equation is derived by introducing the adjoint system. After amplitude is obtained, we compute the linear solutions for super-critical and sub-critical cases. Numerical results for …

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Abundance, Distribution, And Habitat Of The Threatened Minnows Campostoma Ornatum And Notropis Chihuahua In The Trans-Pecos Region Of Texas, Seiji Miyazono, Christopher M. Taylor Jun 2013

Abundance, Distribution, And Habitat Of The Threatened Minnows Campostoma Ornatum And Notropis Chihuahua In The Trans-Pecos Region Of Texas, Seiji Miyazono, Christopher M. Taylor

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Rio Grande and its tributaries in the Trans-Pecos region of Texas have been impacted by a variety of anthropogenic activities such as dewatering and the introduction of nonnative species. These environmental manipulations have negatively affected the native fishes leading to extirpations and declining populations throughout the region. Campostoma ornatum and Notropis chihuahua inhabit tributary streams of the Rio Grande in the Trans-Pecos region and are considered as state-listed threatened species. Little is known about their status and ecological requirements in the region. We hypothesized that the distribution and abundance of these threatened minnows in these spring-fed habitats can be …

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Simulation Of Electronic Processes Of Nanoenergetic Gas Generator Using Cabrera Mott Oxidation Model, Zamart Ramazanova Jun 2013

Simulation Of Electronic Processes Of Nanoenergetic Gas Generator Using Cabrera Mott Oxidation Model, Zamart Ramazanova

Theses and Dissertations - UTB/UTPA

This research study is a theoretical framework for understanding rapid thermal processes which occur during the performance of new Nanoenergetic Gas-Generators (NGG) systems that rapidly release a large amount of gaseous products and generate a fast-moving thermal wave during the explosion. The kinetics of rapid oxidation of metal nanoparticles acquires practical importance with the quickly developing nanoenergetic systems. The thin film oxidation theory of Cabrera-Mott model was examined for a spherically symmetric case and used to analyze the physical importance of the exothermic processes for prediction of the reaction time and front velocity. A rapid kinetic of oxide growth on …

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Algebro-Geometric Solutions For The Degasperis--Procesi Hierarchy, Yu Hou, Peng Zhao, Engui Fan, Zhijun Qiao May 2013

Algebro-Geometric Solutions For The Degasperis--Procesi Hierarchy, Yu Hou, Peng Zhao, Engui Fan, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

Though the completely integrable Camassa--Holm (CH) equation and Degasperis--Procesi (DP) equation are cast in the same peakon family, they possess the second- and third-order Lax operators, respectively. From the viewpoint of algebro-geometrical study, this difference lies in hyper-elliptic and non-hyper-elliptic curves. The non-hyper-elliptic curves lead to great difficulty in the construction of algebro-geometric solutions of the DP equation. In this paper, we derive the DP hierarchy with the help of Lenard recursion operators. Based on the characteristic polynomial of a Lax matrix for the DP hierarchy, we introduce a third order algebraic curve $\mathcal{K}_{r-2}$ with genus $r-2$, from which the …

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Generalized Local Test For Local Extrema In Single-Variable Functions, Eleftherios Gkioulekas May 2013

Generalized Local Test For Local Extrema In Single-Variable Functions, Eleftherios Gkioulekas

School of Mathematical & Statistical Sciences Faculty Publications

We give a detailed derivation of a generalization of the second derivative test of single-variable calculus which can classify critical points as local minima or local maxima (or neither), whenever the traditional second derivative test fails, by considering the values of higher-order derivatives evaluated at the critical points. The enhanced test is local, in the sense that it is only necessary to evaluate all relevant derivatives at the critical point itself, and it is reasonably robust. We illustrate an application of the generalized test on a trigonometric function where the second derivative test fails to classify some of the critical …

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Biochemical, Nutrient And Inhibitory Characteristics Of Streptomyces Cultured From A Hypersaline Estuary, The Laguna Madre (Texas), Luis E. Espinoza, Anita L. Davelos Baines, Kristine L. Lowe May 2013

Biochemical, Nutrient And Inhibitory Characteristics Of Streptomyces Cultured From A Hypersaline Estuary, The Laguna Madre (Texas), Luis E. Espinoza, Anita L. Davelos Baines, Kristine L. Lowe

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Streptomyces are common soil bacteria that produce secondary metabolites, including several antibiotics; however, the characteristics of marine Streptomyces are largely unknown. Sediment samples were taken from 3 sites in the Laguna Madre to isolate marine Streptomyces. Sediment was diluted, spread onto synthetic seawater media to estimate the total bacterial density of the samples and spread onto starch casein agar to isolate Streptomyces. Isolated Streptomyces were tested for salinity tolerance and optimal growth pH. Isolates were assayed using API 20E® test strips and BIOLOG™ plates to construct biochemical profiles and assess nutrient utilization abilities of the bacteria, respectively. Individual Streptomyces were …

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A Model For The Micro-Doppler Effect Of The Quadrupedal Body Motion, Noe Pena May 2013

A Model For The Micro-Doppler Effect Of The Quadrupedal Body Motion, Noe Pena

Theses and Dissertations - UTB/UTPA

In radar returns from quadrupedal body motion the micro-Doppler effect is present. This effect can be used to identify and distinguish this motion from others. In this work the model for the micro-Doppler effect due to quadrupedal motion is developed from Maxwell’s equations. The common gait for all quadrupedal mammal motion is described and analyzed. The radar crossection of quadrupedal motion backscattering is discussed. Quadrupedal motion is simulated and the radar returns are analyzed. The micro-Doppler signatures are decomposed and kinematic parameters are extracted

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Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia May 2013

Predicted Effects Of Climate Change On The Distribution Of The Invasive Grass Dichanthium Annulatum, Cynthia Isabel Garcia

Theses and Dissertations - UTB/UTPA

Kleberg bluestem (Dichanthium annulatum) is an invasive grass species native to Africa but now found in southern United States, Mexico, and other tropical and subtropical countries throughout the world. Using the modeling software MaxEnt, climatic variables from WorldClim, the Intergovernmental Panel on Climate Change (IPCC) scenario A1B, and two General Circulatory Models: the Canadian model (Canadian Centre for Climate Modelling and Analysis or CCCMA), and the Australian model (Commonwealth Scientific and Industrial Research Organisation or CSIRO), several models were developed to determine the possible implications of climatic change on the suitable habitat for D. annulatum, in the year 2050. Models …

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Nascent Nanocomputers: Dna Self-Assembly In O(1) Stages, Michael C. Barnes May 2013

Nascent Nanocomputers: Dna Self-Assembly In O(1) Stages, Michael C. Barnes

Theses and Dissertations - UTB/UTPA

DNA self-assembly offers a potential for nanoscale microcircuits and computers. To make that potential possible requires the development of reliable and efficient tile assembly models. Efficiency is often achieved by minimizing tile complexity, as well as by evaluating the cost and reliability of the specific elements of each tile assembly model. We consider a 2D tile assembly model at temperature 1. The standard 2D tile assembly model at temperature 1 has a tile complexity of O(n) for the construction of exact, complete n x n squares. However, previous research found a staged tile assembly model achieved a tile complexity of …

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Proper Orthogonal Decomposition Of High-Speed Flows, Oscar Huerta May 2013

Proper Orthogonal Decomposition Of High-Speed Flows, Oscar Huerta

Theses and Dissertations - UTB/UTPA

In an effort to understand physical characteristics of high speed flows such as an Impinging Jet (Mach 1.5) and Pulsed Jet (Mach 0.3) both propulsions systems are investigated from phased-locked Particle Image Velocimetry (PIV) data that is analyzed using Proper Orthogonal Decomposition (POD). The purpose of POD is to extract the most dominant features found in the flow. The method calculates the eigenvalues and the spatial eigenfunctions that are related to the total kinetic energy with only a few basis functions. Results for an Impinging Jet show about 70% of the energy in the first twenty modes that represent the …

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An Analysis Of An Exemplary South Texas Charter School, Mario H. Salinas May 2013

An Analysis Of An Exemplary South Texas Charter School, Mario H. Salinas

Theses and Dissertations - UTB/UTPA

Charter schools have emerged as a powerful force in American school reform. When first introduced in 1991, charter schools came with two distinct promises: to serve as an escape hatch for students in failing schools, and to create and incubate new educational practices. Through qualitative inquiry, this study examines a charter school’s best practices and how some of these practices can be applied or emulated in a traditional public school setting. The goal is not to replace traditional public school practices with charter school practices, but to emulate charter school practices that have shown to be successful. The Chief Executive …

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Evolution Of Complex Features In Digital Organisms, Javier A. Magana May 2013

Evolution Of Complex Features In Digital Organisms, Javier A. Magana

Theses and Dissertations - UTB/UTPA

This thesis examines how complex features evolve in digital organisms, and how capabilities that evolved earlier provide a scaffold for evolving new features. I wanted to see how the organisms used previous adaptations to succeed in new environments, and how significant are these previous adaptations. The system used is the Avida platform, which is software that implements Darwinian evolution on self-replicating digital organisms. First, the system is seeded with ancestors that can only replicate, which gave a baseline for the quality of the task at the end of evolution. Second, the system used ancestors from a simpler environment as seeds. …

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Compressed Sensing For Multiple Input-Multiple Output Radar Imaging, Juan F. Lopez Jr. May 2013

Compressed Sensing For Multiple Input-Multiple Output Radar Imaging, Juan F. Lopez Jr.

Theses and Dissertations - UTB/UTPA

Multiple input - multiple output (MIMO) radar utilizes the transmission of spatially diverse waveforms from a static antenna array to gather information about the desired scene. We will demonstrate how techniques from compressed sensing can be applied to image formation in MIMO radar when in the presence of undersampling. We analyze the problem under the general theoretical framework of inverse scattering.

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