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Utb/Tsc Undergraduate Catalog 2010-2011, University Of Texas At Brownsville, Texas Southmost College

UTB/TSC Archives - Course Catalogs

No abstract provided.

Foreign Portfolio Investment Inflows To The United States: The Impact Of Investor Risk Aversion And U.S. Stock Market Performance, Peter V. Egly, David W. Johnk, Daniel Perez Liston

School of Economics and Finance Faculty Publications

This paper examines the relationship of net foreign portfolio investment inflows, namely corporate bonds and stocks, to two pull factors; investor risk aversion and the US stock market. Using a vector autoregressive model, we find that positive shocks to the stock market elicit an insignificant response to the net corporate bond inflow and a significant short term positive response to the net corporate stock inflow. The net corporate stock inflow does not respond to risk aversion, while bond inflows do exhibit a significant midterm response to an increase in risk aversion. Consistent with previous empirical findings, the results show that …

A Quadratic Lower Bound For Rocchio’S Similarity-Based Relevance Feedback Algorithm With A Fixed Query Updating Factor, Zhixiang Chen, Bin Fu, John P. Abraham

Computer Science Faculty Publications

Rocchio’s similarity-based relevance feedback algorithm, one of the most important query reformation methods in information retrieval, is essentially an adaptive supervised learning algorithm from examples. In practice, Rocchio’s algorithm often uses a fixed query updating factor. When this is the case, we strengthen the linear Ω(n) lower bound obtained by Chen and Zhu (Inf. Retr. 5:61–86, 2002) and prove that Rocchio’s algorithm makes Ω(k(n−k)) mistakes in searching for a collection of documents represented by a monotone disjunction of k relevant features over the n-dimensional binary vector space {0,1}n, …

Continuing Studies In Rio Grande Valley History, Milo Kearney, Anthony K. Knopp, Antonio Zavaleta

Studies in Rio Grande Valley Regional History Series

Coming to the Valley, a poem / Vivian Kearney -- The ghosts of historic Palmito Hill Ranch / Antonio N. Zavaleta -- Against the odds : Dr. Juliet V. García, border educator / Manuel F. Medrano -- Lucile Champion's Brownsville : remembrances of another time / Frank Champion Murphy -- The restored courthouse and Judge Oscar Dancy / Anthony Knopp -- Francesco Voltaggio and the Port Isabel shrimp industry / Virginia Voltaggio Wood -- Mario Barrera : a border success story / Milo Kearney -- Selected figures from the Sierra/Valerio family history / Luciano Valerio Sierra and Amy Sierra Frazier …

Hyperbolic Systems Modeling Currency Hoarding, Elena Quercioli, Jeffrey Rauch

School of Economics and Finance Faculty Publications

We introduce and analyse linear systems of hyperbolic partial differential equations that model the replacement and hoarding of currency. The goal is to deduce the hoarding behavior from observations of circulating bills. The large time asymptotics of the models is identified in all cases. The mathematical analysis is novel, partly because of nonstandard boundary conditions. To identify parameters we suggest the measurement of the age histogram of notes, the rate of growth, and the retard in wear of notes due to hoarding. In our models that suffices to identify all but one quantity.

Possibilities: Kamil Jbeily–The Man And His Vision For The Texas Regional Collaboratives For Excellence In Science And Mathematics Teaching, Martha May Tevis, John Mcbride

Teaching and Learning Faculty Publications

No abstract provided.

Technology Integration In Teaching Action Research, Alcione N. Ostorga

Bilingual and Literacy Studies Faculty Publications

This article describes an instructional model designed to teach action research to undergraduate preservice teachers, which uses technology integration to facilitate the learning process that incorporates face to face and distance learning methods. First, a theoretical overview of the instructional design is provided then the instructional model is described. The course design is analyzed through the use of Moore's levels of interaction. Finally, the author discusses the conclusions and implications for future research.

The Role Of Fat Mass Index In Determining Obesity, Gerson Peltz, Maria Teresa Aguirre, Maureen Sanderson, Mary K. Fadden

Health & Biomedical Sciences Faculty Publications

Objectives: The objective of this study is to compare body mass index (BMI), percent body fat (PBF), and fat mass index (FMI) and to investigate the accuracy of FMI as a convenient tool for assessing obesity.

Design: Anthropometric measurements and bioelectrical impedance analyses were performed on 538 Mexican Americans (373 women and 165 men). Correlations between BMI and PBF and between FMI and PBF were investigated. The percentage of persons misclassified as obese using different classifications was calculated. Multiple linear regression analysis was performed to generate predictive models of FMI for males and females separately.

Results: BMI and PBF were …

Triplets Of Supermassive Black Holes: Astrophysics Gravitational Waves And Detection, Pau Amaro-Seoane, Alberto Sesana, Loren Hoffman, Matthew Benacquista, Christoph Eichhorn, Junichiro Makino, Rainer Spurzem

Physics & Astronomy Faculty Publications

Supermassive black holes (SMBHs) found in the centres of many galaxies are understood to play a fundamental, active role in the cosmological structure formation process. In hierarchical formation scenarios, SMBHs are expected to form binaries following the merger of their host galaxies. If these binaries do not coalesce before the merger with a third galaxy, the formation of a black hole triple system is possible. Numerical simulations of the dynamics of triples within galaxy cores exhibit phases of very high eccentricity (as high as e∼ 0.99). During these phases, intense bursts of gravitational radiation can be emitted at orbital periapsis, …

Effects Of Α-Element Enhancement And The Thermally Pulsing-Asymptotic Giant Branch On Surface Brightness Fluctuation Magnitudes And Broadband Colors, Hyun Chul Lee, Guy Worthey, John P. Blakeslee

Physics & Astronomy Faculty Publications

We investigate the effects of α-element enhancement and the thermally pulsing-asymptotic giant branch (TP-AGB) stars on the surface brightness fluctuation (SBF) magnitudes and broadband colors of simple stellar populations and compare to the empirical calibrations. We consider a broad range of ages and metallicities using the recently updated Teramo BaSTI isochrones. We find that the α-element-enhanced I-band SBF magnitudes are about 0.35mag brighter and their integrated V - I colors are about 0.02mag redder, mostly because of oxygen-enhancement effects on the upper red giant branch and AGB. We also demonstrate, using both the Teramo BaSTI and Padova isochrones, the acute …

Search For Gravitational Waves From Compact Binary Coalescence In Ligo And Virgo Data From S5 And Vsr1, J. Abadie, B. P. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We report the results of the first search for gravitational waves from compact binary coalescence using data from the Laser Interferometer Gravitational-Wave Observatory and Virgo detectors. Five months of data were collected during the Laser Interferometer Gravitational-Wave Observatory’s S5 and Virgo’s VSR1 science runs. The search focused on signals from binary mergers with a total mass between 2 and 35M⊙. No gravitational waves are identified. The cumulative 90%-confidence upper limits on the rate of compact binary coalescence are calculated for nonspinning binary neutron stars, black hole-neutron star systems, and binary black holes to be 8.7×10−3  yr−1 L−110, 2.2×10−3  yr−1 L−110, …

The Lisa Gravitational Wave Foreground: A Study Of Double White Dwarfs, Ashley J. Ruiter, Krzysztof Belczynski, Matthew Benacquista, Shane L. Larson, Gabriel Williams

Physics & Astronomy Faculty Publications

Double white dwarfs (WDs) are expected to be a source of confusion-limited noise for the future gravitational wave observatory LISA. In a specific frequency range, this \"foreground noise\" is predicted to rise above the instrumental noise and hinder the detection of other types of signals, e.g., gravitational waves arising from stellar-mass objects inspiraling into massive black holes. In many previous studies, only detached populations of compact object binaries have been considered in estimating the LISA gravitational wave foreground signal. Here, we investigate the influence of compact object detached and Roche-Lobe overflow (RLOF) Galactic binaries on the shape and strength of …

Search For Gravitational-Wave Bursts Associated With Gamma-Ray Bursts Using Data From Ligo Science Run 5 And Virgo Science Run 1, B. P. Abbott, R. Abbott, F. Acernese, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the results of a search for gravitational-wave bursts (GWBs) associated with 137 gamma-ray bursts (GRBs) that were detected by satellite-based gamma-ray experiments during the fifth LIGO science run and first Virgo science run. The data used in this analysis were collected from 2005 November 4 to 2007 October 1, and most of the GRB triggers were from the Swift satellite. The search uses a coherent network analysis method that takes into account the different locations and orientations of the interferometers at the three LIGO-Virgo sites. We find no evidence for GWB signals associated with this sample of GRBs. …

Searches For Gravitational Waves From Known Pulsars With Science Run 5 Ligo Data, B. P. Abbott, R. Abbott, F. Acernese, Teviet Creighton, Matthew Benacquista, Mario C. Diaz, Soumya D. Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present a search for gravitational waves from 116 known millisecond and young pulsars using data from the fifth science run of the LIGO detectors. For this search, ephemerides overlapping the run period were obtained for all pulsars using radio and X-ray observations. We demonstrate an updated search method that allows for small uncertainties in the pulsar phase parameters to be included in the search. We report no signal detection from any of the targets and therefore interpret our results as upper limits on the gravitational wave signal strength. The most interesting limits are those for young pulsars. We present …

Apparent Faster-Than-Light Pulse Propagation In Interstellar Space: A New Probe Of The Interstellar Medium, F. A. Jenet, D. Fleckenstein, A. Ford, A. Garcia, R. Miller, J. Rivera, K. Stovall

Physics & Astronomy Faculty Publications

Radio pulsars emit regular bursts of radio radiation that propagate through the interstellar medium (ISM), the tenuous gas and plasma between the stars. Previously known dispersive properties of the ISM cause low-frequency pulses to be delayed in time with respect to high frequency ones. This effect can be explained by the presence of free electrons in the medium. The ISM also contains neutral hydrogen that has a well-known resonance at 1420.4 MHz. Electromagnetic theory predicts that at such a resonance, the induced dispersive effects will be drastically different from those of the free electrons. Pulses traveling through a cloud of …

Unidirectional Nonlinear Pt-Symmetric Optical Structures, Hamidreza Ramezani, Tsampikos Kottos

Physics & Astronomy Faculty Publications

We show that nonlinear optical structures involving a balanced gain-loss profile can act as unidirectional optical valves. This is made possible by exploiting the interplay between the fundamental symmetries of parity (P) and time (T), with optical nonlinear effects. This unidirectional dynamics is specifically demonstrated for the case of an integrable PT-symmetric nonlinear system.

Particle Swarm Optimization And Gravitational Wave Data Analysis: Performance On A Binary Inspiral Testbed, Yan Wang, Soumya Mohanty

Physics & Astronomy Faculty Publications

The detection and estimation of gravitational wave signals belonging to a parameterized family of waveforms requires, in general, the numerical maximization of a data-dependent function of the signal parameters. Because of noise in the data, the function to be maximized is often highly multimodal with numerous local maxima. Searching for the global maximum then becomes computationally expensive, which in turn can limit the scientific scope of the search. Stochastic optimization is one possible approach to reducing computational costs in such applications. We report results from a first investigation of the particle swarm optimization method in this context. The method is …

All-Sky Search For Gravitational-Wave Bursts In The First Joint Ligo-Geo-Virgo Run, J. Abadie, B. P. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano, Robert Stone

Physics & Astronomy Faculty Publications

We present results from an all-sky search for unmodeled gravitational-wave bursts in the data collected by the LIGO, GEO 600 and Virgo detectors between November 2006 and October 2007. The search is performed by three different analysis algorithms over the frequency band 50–6000 Hz. Data are analyzed for times with at least two of the four LIGO-Virgo detectors in coincident operation, with a total live time of 266 days. No events produced by the search algorithms survive the selection cuts. We set a frequentist upper limit on the rate of gravitational-wave bursts impinging on our network of detectors. When combined …

An Exploratory Investigation Of The Implementation Of Quality Staff Development And Campus Success, Cindy Hays Sadler

Theses and Dissertations - UTB/UTPA

The purpose of this study was to explore what proportion of staff development as measured by the National Staff Development Council’s Standard Assessment Inventory (SAI) contributes to campus success as measured by the Texas Assessment of Knowledge and Skills (TAKS). Two exploratory null hypotheses were generated and tested in an attempt to explore outcomes using the SAI and TAKS scores. H0 Campus Success (Y) based on the Texas Assessment of Knowledge and Skills is not a function of implementation of the National Staff Development Council Standards (X) based on Standard Assessment Inventory. H0 Campus success (Y) is not a function …

Evaluation Of Windows Servers Security Under Icmp And Tcp Denial Of Service Attacks, Hari Krishnea Vallalacheruvu

Theses and Dissertations - UTB/UTPA

Securing server from Distributed denial of service (DDoS) attacks is a challenging task for network operators. DDOS attacks are known to reduce the performance of web based applications and reduce the number of legitimate client connections. In this thesis, we evaluate performance of a Windows server 2003 under these attacks. In this thesis, we also evaluate and compare effectiveness of three different protection mechanisms, namely SYN Cache, SYN Cookie and SYN proxy protection methods, to protect against TCP SYN DDoS attacks. It is found that the SYN attack protection at the server is more effective at lower loads of SYN …

Health Impacts Of Traffic Related Air Pollution, Amit U. Raysoni, Wen-Wahi Li

School of Earth, Environmental, & Marine Sciences Faculty Publications

Ambient air pollution can be a serious cause of concern for any community. Anthropogenic ambient air pollutants can emanate from industries, traffic, geological sources and domestic heating and cooking. However, studies have shown that traffic related air pollution can have far more detrimental health effects than non-combustion sources. These adverse health effects are most profound in sensitive populations like the elderly and young children. The World Health Organization (WHO) attributes more than 300 million deaths every year to ambient air pollution. The WHO’s Air Quality Guidelines (AQG) and the United States Environment Protection Agency’s (USEPA) National Ambient Air Quality Standards …

S2st: A Relational Rdf Database Management System, Anthony T. Piazza

Theses and Dissertations - UTB/UTPA

The explosive growth of RDF data on the Semantic Web drives the need for novel database systems that can efficiently store and query large RDF datasets. To achieve good performance and scalability of query processing, most existing RDF storage systems use a relational database management system as a backend to manage RDF data. In this paper, we describe the design and implementation of a Relational RDF Database Management System. Our main research contributions are: (1) We propose a formal model of a Relational RDF Database Management System (RRDBMS), (2) We propose generic algorithms for schema, data and query mapping, (3) …

Utilizing Concept Mapping As A Teaching And Learning Tool To Prepare For The Science Taks Test, Rosa Linda Zuniga

Theses and Dissertations - UTB/UTPA

Concept mapping was used with Donna High School students to determine its effect on the Texas Assessment of Knowledge and Skills (TAKS) test. Concept mapping was used with models such as the Sheltered Instruction Observation Protocol model (SIOP), the 5- E model, and the Learning Groups model. This measure was taken because the models used have not helped students improve their TAKS scores significantly. The findings of this research reveals that using the process of concept mapping together with the SIOP model helps students clearly see related concepts and motivates them to think more deeply. Students quickly realize what concepts …

Spatial Instability Of Electrically Driven Jets With Finite Conductivity And Under Constant Or Variable Applied Field, Saulo Orizaga, Daniel N. Riahi

School of Mathematical & Statistical Sciences Faculty Publications

We investigate the problem of spatial instability of electrically driven viscous jets with finite electrical conductivity and in the presence of either a constant or a variable applied electric field. A mathematical model, which is developed and used for the spatially growing disturbances in electrically driven jet flows, leads to a lengthy equation for the unknown growth rate and frequency of the disturbances. This equation is solved numerically using Newton’s method. For neutral temporal stability boundary, we find, in particular, two new spatial modes of instability under certain conditions. One of these modes is enhanced by the strength Ω of …

Timing Stability Of Millisecond Pulsars And Prospects For Gravitational-Wave Detection, J. P.W. Verbiest, M. Bailes, W. A. Coles, G. B. Hobbs, W. Van Straten, D. J. Champion, Fredrick A. Jenet, R. N. Manchester, N. D.R. Bhat, J. M. Sarkissian

Physics & Astronomy Faculty Publications

The analysis of high-precision timing observations of an array of ∼20 millisecond pulsars (a so-called 'timing array') may ultimately result in the detection of a stochastic gravitational-wave background. The feasibility of such a detection and the required duration of this type of experiment are determined by the achievable rms of the timing residuals and the timing stability of the pulsars involved. We present results of the first long-term, high-precision timing campaign on a large sample of millisecond pulsars used in gravitational-wave detection projects. We show that the timing residuals of most pulsars in our sample do not contain significant low-frequency …

The Pan American (2009-11-19), Brian Silva

UTPA Archives - The Pan American Newspaper

Vol. 66, No. 12

Comparison Of Alpha-Element-Enhanced Simple Stellar Population Models With Milky Way Globular Clusters, Hyun Chul Lee, Guy Worthey, Aaron Dotter

Physics & Astronomy Faculty Publications

We present simple stellar population (SSP) models with scaled-solar and α-element-enhanced abundances. The SSP models are based on the Dartmouth Stellar Evolution Database, our library of synthetic stellar spectra, and a detailed systematic variation of horizontal-branch (HB) morphology with age and metallicity. In order to test the relative importance of a variety of SSP model ingredients, we compare our SSP models with integrated spectra of 41 Milky Way globular clusters (MWGCs) from Schiavon etal. Using the Mg b and Ca4227 indices, we confirm that Mg and Ca are enhanced by about +0.4 and +0.2dex, respectively, in agreement with results from …

Characterization Of Arsenic-Tolerant Bacterial Cultures From The Lower Laguna Madre Of South Texas, Gemma A. Berlanga, Michael W. Persans, Thomas Eubanks, Kristine L. Lowe

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

Two forms of arsenic are found in the environment: As(V) and As(III), the latter being more toxic, water-soluble, and mobile. Microorganisms may increase the mobility of arsenic by reducing As(V) to As(III); however, detoxification and immobilization can occur via the oxidation of As(III) to As(V). The US EPA has set a minimum contaminant level of 10 parts per billion (ppb) for arsenic in drinking water. The research objective was to confirm the presence of arsenic-tolerant bacteria in the Lower Laguna Madre of south Texas. Sediment samples were collected and inoculated into growth media which contained either 2 mM As(III) or …

The Collegian (2009-10-26), Julianna Sosa

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 62, No. 10

The Collegian (2009-10-19), Julianna Sosa

UTB/TSC Archives - The Collegian [Newspaper]

Vol. 62, No. 9