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Probabilistic Shortest Time Queries Over Uncertain Road Networks, Yaqing Chen May 2014

Probabilistic Shortest Time Queries Over Uncertain Road Networks, Yaqing Chen

Theses and Dissertations - UTB/UTPA

In many real applications such as location-based services (LBS), map utilities, trip planning, and transportation systems, it is very useful and important to provide query services over spatial road networks. Nowadays we can easily obtain rich traffic information such as the speeds of vehicles on roads. However, due to the inaccuracy of devices or integration in consistencies, the traffic data (i.e., speeds) are often imprecise and uncertain. In this paper, we model road networks by uncertain graphs, which contain edges that are associated with probabilistic velocities. We formalize the problem of probabilistic shortest time query, and we propose time bound …

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School Principals' Perceptions Of Bilingual Education And Their Relation To English Language Learners' 8th Grade Reading Performance On Staar, Imelda Mares May 2014

School Principals' Perceptions Of Bilingual Education And Their Relation To English Language Learners' 8th Grade Reading Performance On Staar, Imelda Mares

Theses and Dissertations - UTB/UTPA

This research examined school principals’ perceptions of bilingual education to determine whether perceptions were a function of gender, age, years of experience, level of academic knowledge of bilingual education, and language discourse or bilingualism. Moreover, this study explored whether principals’ perceptions of bilingual education were related to English language learners’ 8th grade reading performance as measured by the State of Texas Assessments of Academic Readiness (STAAR). Thirty-one middle and high school principals in five school districts from south Texas and one district from southeast Texas responded to an electronic survey that solicited demographic information, perceptions of bilingual education, and academic …

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Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez May 2014

Monitoring Citrus Nutrition In The Rio Grande Valley For Fertilizer Recommendations, Iram Lopez

Theses and Dissertations - UTB/UTPA

Soil fertility and plant nutrition is crucial for a better yield and consistent harvest in the Rio Grande Valley for local farmers growing citrus trees. A field of oranges and a field of grapefruits were monitored and nutrition deficiencies were noticed that played an important role during fruit set. Soil samples that were taken throughout the year were analyzed via a carbon dioxide extraction method that mimics the way plants naturally take up nutrients or extract nutrients from every soil type. Macronutrients such as the N, P, K, Na, Ca, Mg and some of the micronutrients (Zn, Fe, Mn, and …

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Creating An Information Systems Security Culture Through An Integrated Model Of Employees Compliance, Mohammad I. Merhi May 2014

Creating An Information Systems Security Culture Through An Integrated Model Of Employees Compliance, Mohammad I. Merhi

Theses and Dissertations - UTB/UTPA

Employees’ non-compliance with information systems security policies has been identified as a major threat to organizational data and information systems. This dissertation investigates the process underlying information systems security compliance in organizations with the focus on employees. The process model is complex, comprising many normative, attitudinal, psychological, environmental, and organizational factors. Therefore, the study of information security compliance requires a holistic assessment of all these factors. This dissertation seeks to achieve this objective by offering a comprehensive and integrated model of employee behavior especially focused towards information security compliance. The research framework is influenced by the Reciprocal Determinism Theory which …

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Creating Her Own Power: "Morte Darthur's" Morgan Le Fay, Cynthia A. Scott May 2014

Creating Her Own Power: "Morte Darthur's" Morgan Le Fay, Cynthia A. Scott

Theses and Dissertations - UTB/UTPA

Morgan le Fay is one of the most recognizable female characters in Thomas Malory’s Morte Darthur as she persistently creates conflict for King Arthur and his knights. While many scholars have focused on the idea of a subjugated female presence in Malory’s text, this paper addresses the power that Morgan displays and how it suggests underlying masculine anxieties existing in a patriarchy. Three specific components of Morgan’s power are discussed: her ability to reject and manipulate prescribed gender codes, her power of enchantment, and her disruption of homosocial bonds. The strategic combination of these three components allows Morgan to exhibit …

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A Decision Support System To Measure Product Suitability For Additive Manufacturing Processes, Cynthia De Vasconcellos Barros May 2014

A Decision Support System To Measure Product Suitability For Additive Manufacturing Processes, Cynthia De Vasconcellos Barros

Theses and Dissertations - UTB/UTPA

Additive Manufacturing (AM) technologies started arising around 1980’s and they are currently considered to be the third industrial revolution. With improvements in computers, materials, and automated machines, manufacturers across several types of industries are becoming more familiar with AM processes, and it has become more common to see products that are being fabricated by using this new technology. However, there are still questions regarding when it is suitable to use Additive Manufacturing or conventional manufacturing processes depending on different factors. The purpose of this thesis is to create a Decision Support System (DSS) that will help users measure product suitability …

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Snow Monkeys In South Texas, A Thirty Year Study Of Behavioral Adaptation, Lou E. Griffin May 2014

Snow Monkeys In South Texas, A Thirty Year Study Of Behavioral Adaptation, Lou E. Griffin

Theses and Dissertations - UTB/UTPA

A thirty year study of a transplanted species of primate, Macaca fuscata, Japanese snow monkey, documents the environmental influences on an intact troop relocated from Arashiyama, Japan to south Texas. These influences include novel disease, toxins, and predation. The effects of the environment on the social structure, hierarchy, and population of the primates are presented. The study begins in 1972 and is completed in 2002.

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Cubic B-Spline: Derivation With Two Applications, Maria Mungia May 2014

Cubic B-Spline: Derivation With Two Applications, Maria Mungia

Theses and Dissertations - UTB/UTPA

We investigate the application of cubic B-spline functions in this work. First, we derive the cubic B-spline functions. Then we use these functions for two applications: one for interpolation and the other for solving boundary value problems. For interpolation, we consider two types of boundary conditions, namely natural and clamped. For boundary value problems, we consider constant coefficient and variable coefficient cases. Examples with numerical results are presented for both applications. Also we compare the results obtained using cubic B-spline functions with the results obtained by other methods. For this investigation, it is observed that cubic B-spline gives better results.

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Cloning And Characterization Of Ef-Tu And Ef-Ts From Streptococcus Pneumoniae, Carlos Eduardo Rivera May 2014

Cloning And Characterization Of Ef-Tu And Ef-Ts From Streptococcus Pneumoniae, Carlos Eduardo Rivera

Theses and Dissertations - UTB/UTPA

Antibiotic resistance is a prevalent threat to public health around the world, and resistance among strains of Streptococcus pneumoniae is growing rapidly. This increasing resistance elevates the demand for new drug discoveries. This research attempts to develop a means to combat S. pneumoniae by targeting protein synthesis for the discovery of new antibacterial agents. Protein synthesis components, elongation factor Tu (EF-Tu) and elongation factor Ts (EF-Ts) facilitate many steps in the biosynthesis of proteins and are therefore essential proteins involved in protein synthesis. EF-Tu and EF-Ts were cloned, expressed, purified, and enzymatically characterized to help develop a screening system that …

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Topological Pressure And Fractal Dimensions For Bi-Lipschitz Mappings, Hugo E. Olvera May 2014

Topological Pressure And Fractal Dimensions For Bi-Lipschitz Mappings, Hugo E. Olvera

Theses and Dissertations - UTB/UTPA

In this thesis, first we have defined the topological pressure P(t) and then using Banach limit we have determined a unique Borel probability measure µh supported by the invariant set E of a system of bi-Lipschitz mappings where h is the unique zero of the pressure function. Using the topological pressure and the measure µh, under certain condition on bi-Lipschitz constants, we have shown that the fractal dimensions such as the Hausdorff dimension, the packing dimension and the box-counting dimension of the set E are all equal to h. Moreover, it is shown that the h-dimensional Hausdorff measure and the …

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Exponential Replication Of Patterns In The Signal Tile Assembly Model And Experimental Non-Deterministic Assembly Of Lines In The Probabilistic Tile Assembly Model, Alexandra B. Keenan May 2014

Exponential Replication Of Patterns In The Signal Tile Assembly Model And Experimental Non-Deterministic Assembly Of Lines In The Probabilistic Tile Assembly Model, Alexandra B. Keenan

Theses and Dissertations - UTB/UTPA

We introduce the problem of self-replication of rectangular two-dimensional patterns in the practically motivated Signal Tile Assembly Model (STAM), which is an extension of the aTAM. In the first part of this thesis, we construct an exponential pattern replicator that replicates a two-dimensional input pattern over some fixed alphabet of size ϕ with O(ϕ) tile types, O(ϕ) unique glues, and a signal complexity of O(1). In the second part of this thesis, we use a non-deterministic model of tile assembly to significantly reduce the tile complexity of specified-length linear assemblies, which are a particularly important substructure for building more complicated …

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Benefits Of Using Reading Strategies In Elementary Bilingual Classrooms, Diana Arely Garcia May 2014

Benefits Of Using Reading Strategies In Elementary Bilingual Classrooms, Diana Arely Garcia

Theses and Dissertations - UTB/UTPA

This quantitative study focused on the benefits of reading strategies used by second grade students. What strategies they can use to comprehend tasks, what textual cues they attend, how to make sense of what they read, and what they do when they do not understand a word. In this study, a questionnaire was given to the students. The questionnaire had a list of reading strategies in which students chose the strategy they felt more comfortable to use whenever they needed in order to comprehend a text. The data collected was analyzed and served its purpose of helping one reach the …

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Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani, F. M. Ellis, T. Kottos Apr 2014

Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani, F. M. Ellis, T. Kottos

Physics & Astronomy Faculty Publications

Using a pair of coupled RLC cavities we experimentally demonstrate that amplification action can be tamed by a spatially inhomogeneous gain. Under specific conditions we observe the counterintuitive phenomenon of stabilization of the system even when the overall gain provided is increased. This behavior is directly related to lasing shutdown via asymmetric pumping, recently proposed in M. Liertzer et al. [Phys. Rev. Lett. 108, 173901 (2012)]. The analysis of other simple systems reveals the universal nature of the lasing shutdown phenomenon as having its roots in managing impedance matching.

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The Collegian (2014-04-28), Cleiri Quezada Apr 2014

The Collegian (2014-04-28), Cleiri Quezada

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 66, No. 28

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Bifurcation Type Change Of Ac Electrostatically Actuated Mems Resonators Due To Dc Bias, Dumitru Caruntu, Kyle N. Taylor Apr 2014

Bifurcation Type Change Of Ac Electrostatically Actuated Mems Resonators Due To Dc Bias, Dumitru Caruntu, Kyle N. Taylor

Mechanical Engineering Faculty Publications

This paper investigates the nonlinear response of microelectromechanical system (MEMS) cantilever resonator electrostatically actuated by applying a soft alternating current (AC) voltage and an even softer direct current (DC) voltage between the resonators and a parallel fixed ground plate. The AC frequency is near natural frequency. This drives the resonator into nonlinear parametric resonance. The method ofmultiple scales (MMS) is used to solve the dimensionless differential equation of motion of the resonator and find the steady-state solutions.The reduced order model (ROM) method is used to validate the results obtained using MMS. The effect of the soft DC voltage (bias) component …

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Communication: Conical Intersections Between Vibrationally Adiabatic Surfaces In Methanol, Mahesh B. Dawadi, David S. Perry Apr 2014

Communication: Conical Intersections Between Vibrationally Adiabatic Surfaces In Methanol, Mahesh B. Dawadi, David S. Perry

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

A set of seven conical intersections (CI’s) in methanol between vibrationally adiabatic surfaces is reported. The intersecting surfaces represent the energies of the two asymmetric CH stretch vibrations regarded as adiabatic functions of the torsion and COH bend angles. The ab initio data are well described by an extended Zwanziger and Grant (E ⊗ e) model [J. W. Zwanziger and E. R. Grant, J. Chem. Phys. 87, 2954 (1987)] that might also be regarded as an extension of the XHL model [L.-H. Xu, J. T. Hougen, and R. M. Lees, J. Mol. Spectrosc. 293–294, 38 (2013)]. …

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Optical Isolation Via Pt-Symmetric Nonlinear Fano Resonances, F. Nazari, N. Bender, Hamidreza Ramezani, M. K. Moravvej-Farshi, D. N. Christodoulides, T. Kottos Apr 2014

Optical Isolation Via Pt-Symmetric Nonlinear Fano Resonances, F. Nazari, N. Bender, Hamidreza Ramezani, M. K. Moravvej-Farshi, D. N. Christodoulides, T. Kottos

Physics & Astronomy Faculty Publications

We show that Fano resonances created by twoPT -symmetric nonlinear micro-resonators coupled to a waveguide, have line-shape and resonance position that depends on the direction of the incident light. We utilize these features in order to induce asymmetric transport, up to 47 dBs, in the optical C-window. Our theoretical proposal requires low input power and does not compromise the power or frequency characteristics of the output signal.

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The Collegian (2014-04-21), Cleiri Quezada Apr 2014

The Collegian (2014-04-21), Cleiri Quezada

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 66, No. 27

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Gravitational Waves From Known Pulsars: Results From The Initial Detector Era, J. Aasi, J. Abadie, B. P. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Walter Ortega Larcher, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano Apr 2014

Gravitational Waves From Known Pulsars: Results From The Initial Detector Era, J. Aasi, J. Abadie, B. P. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Walter Ortega Larcher, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and …

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The Collegian (2014-04-07), Cleiri Quezada Apr 2014

The Collegian (2014-04-07), Cleiri Quezada

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 66, No. 26

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Utb/Tsc Commencement – Winter 2014, University Of Texas At Brownsville, Texas Southmost College Apr 2014

Utb/Tsc Commencement – Winter 2014, University Of Texas At Brownsville, Texas Southmost College

Brownsville Archives - Legacy Commencement Programs

No abstract provided.

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Utb/Tsc Commencement – Spring 2014, University Of Texas At Brownsville, Texas Southmost College Apr 2014

Utb/Tsc Commencement – Spring 2014, University Of Texas At Brownsville, Texas Southmost College

Brownsville Archives - Legacy Commencement Programs

No abstract provided.

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Utpa Commencement – Spring 2014, University Of Texas-Pan American Apr 2014

Utpa Commencement – Spring 2014, University Of Texas-Pan American

Edinburg Archives - Legacy Commencement Programs

No abstract provided.

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Fermi-Normal, Optical, And Wave-Synchronous Coordinates For Spacetime With A Plane Gravitational Wave, Malik Rakhmanov Apr 2014

Fermi-Normal, Optical, And Wave-Synchronous Coordinates For Spacetime With A Plane Gravitational Wave, Malik Rakhmanov

Physics & Astronomy Faculty Publications

Fermi-normal (FN) coordinates provide a standardized way to describe the effects of gravitation from the point of view of an inertial observer. These coordinates have always been introduced via perturbation expansions and were usually limited to distances much less than the characteristic length scale set by the curvature of spacetime. For a plane gravitational wave this scale is given by its wavelength which defines the domain of validity for these coordinates known as the long-wavelength regime. The symmetry of this spacetime, however, allows us to extend FN coordinates far beyond the long-wavelength regime. Here we present an explicit construction for …

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Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani Apr 2014

Experimental Observation Of Lasing Shutdown Via Asymmetric Gain, M. Chitsazi, S. Factor, J. Schindler, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

Using a pair of coupled RLC cavities we experimentally demonstrate that amplification action can be tamed by a spatially inhomogeneous gain. Under specific conditions we observe the counterintuitive phenomenon of stabilization of the system even when the overall gain provided is increased. This behavior is directly related to lasing shutdown via asymmetric pumping, recently proposed in M. Liertzer et al. [Phys. Rev. Lett. 108, 173901 (2012)]. The analysis of other simple systems reveals the universal nature of the lasing shutdown phenomenon as having its roots in managing impedance matching.

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Temperature And Relative Humidity Effects On Water Loss And Hemolymph Osmolality Of Littoraria Angulifera (Lamarck, 1822), Phillip J. Rose Apr 2014

Temperature And Relative Humidity Effects On Water Loss And Hemolymph Osmolality Of Littoraria Angulifera (Lamarck, 1822), Phillip J. Rose

Theses and Dissertations - UTB/UTPA

Desiccation stress is considered to be one of the more significant determining factors that influence how organisms are distributed in the marine littoral. Gastropods living above the high tide mark, referred to as eulittoral fringe gastropods are not wetted as regularly and face unpredictable and prolonged periods of emersion. Consequently, adaptations displayed by eulittoral fringe gastropods are aimed at minimizing water loss and surviving prolonged periods of desiccation stress. Littoraria angulifera, is a tropically distributed marine eulittoral fringe gastropod. Because L. angulifera spends a majority of its time emersed there was interest in studying how the weight loss and hemolymph …

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On Toroidal Knots, Chirality, And Molecules, Ramiro Garza Apr 2014

On Toroidal Knots, Chirality, And Molecules, Ramiro Garza

Theses and Dissertations - UTB/UTPA

The inspiration for this thesis came from two sources: the book When topology meets chemistry: a topological look at molecular chirality, by Erica Flapan [7], which discusses topologically interesting molecules; and the paper All toroidal embeddings of polyhedral graphs in 3-space are chiral, by T. Castle et al., which proves that toroidal embeddings of polyhedra are chiral. Their proof is examined in detail. A possible application of this work, as discussed by the team, would be in molecules which have the structure of a toroidal polyhedral embedding. Various methods of seeking such an example are attempted and discussed.

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The Role Of App Development And Mobile Computing In Motivating The Secondary Mathematics Classroom, Jennifer Lee Marquez Apr 2014

The Role Of App Development And Mobile Computing In Motivating The Secondary Mathematics Classroom, Jennifer Lee Marquez

Theses and Dissertations - UTB/UTPA

An increasing amount of high school students are interested in developing their own mobile application. Incorporating mobile development into the classroom can increase student engagement in the fields of science, technology, engineering, and mathematics. In this paper I present a study done with a group of sophomore level students who created their own mathematics apps with no programming experience. The aim of this study is to assess the knowledge gained and motivational appeal of secondary mathematics students taught basic state of Texas exam concepts with the use of the proposed mobile development labs. Students in this study used algebraic and …

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A Digital Backend For The Low Frequency All Sky Monitor, Louis Percy Dartez Apr 2014

A Digital Backend For The Low Frequency All Sky Monitor, Louis Percy Dartez

Theses and Dissertations - UTB/UTPA

The Low Frequency All Sky Monitor (LoFASM) is a distributed array of dipole antennas that are sensitive to radio frequencies from 10 to 88 MHz. The primary science goals of LoFASM are the detection and study of low-frequency radio transients, a high priority science goal as deemed by the National Research Council's decadal survey. LoFASM consists of antennas and front-end electronics that were originally developed for the Long Wavelength Array (LWA) by the U.S. Naval Research Lab, the University of New Mexico, Virginia Tech, and the Jet Propulsion Laboratory. LoFASM, funded by the U.S. Department of Defense, will initially consist …

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Prepubertal Exposure To Arsenic(Iii) Suppresses Circulating Insulin-Like Growth Factor-1 (Igf-1) Delaying Sexual Maturation In Female Rats, Michael P. Reilly, James C. Saca, Alina Hamilton, Rene F. Solano, Jesse R. Rivera, Wendy Innis-Whitehouse, Jason Parsons, Robert K. Dearth Apr 2014

Prepubertal Exposure To Arsenic(Iii) Suppresses Circulating Insulin-Like Growth Factor-1 (Igf-1) Delaying Sexual Maturation In Female Rats, Michael P. Reilly, James C. Saca, Alina Hamilton, Rene F. Solano, Jesse R. Rivera, Wendy Innis-Whitehouse, Jason Parsons, Robert K. Dearth

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

Arsenic (As) is a prevalent environmental toxin readily accessible for human consumption and has been identified as an endocrine disruptor. However, it is not known what impact As has on female sexual maturation. Therefore, in the present study, we investigated the effects of prepubertal exposure on mammary gland development and pubertal onset in female rats. Results showed that prepubertal exposure to 10 mg/kg of arsenite (As(III)) delayed vaginal opening (VO) and prepubertal mammary gland maturation. We determined that As accumulates in the liver, disrupts hepatocyte function and suppresses serum levels of the puberty related hormone insulin-like growth factor 1 (IGF-1) …

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