Physical Sciences and Mathematics Commons^™

Resolutions And Tor Algebra Structures For Trivariate Monomial Ideals, Jared Lafayette Painter

Mathematics Dissertations

In this manuscript we explore properties of minimal free resolutions and their relationship to the Tor-algebra structure for trivariate monomial ideals. We begin with an in-depth analysis of minimal free resolutions of S = R / I, where R = k[x; y; z] is a polynomial ring over a field k, and I is a monomial ideal that is primary to the homogeneous maximal ideal m of R. We will de ne a special form of the minimal free resolution of S, and then determine when we get nonzero elements from I as entries in the matrices of the resolution. …

High Order Dns For Late Flow Transition, Ping Lu

Mathematics Dissertations

In this report, a new high order scheme for boundary points is introduced when calculating the derivative of smooth functions by Compact Scheme. The primitive function reconstruction method of ENO schemes is applied to obtain the conservative form of the Compact Scheme. Meanwhile, modified compact scheme is developed by using an effective shock detector to block upwinding compact scheme to cross the shock, a control function, and an adaptive scheme which uses some WENO flux near the shock. The new scheme makes the original upwinding compact scheme able to capture the shock sharper than WENO and, more important, keep high …

New Results In Finite Geometries Pertaining To Albert-Like Semifields, Angela Michelle Brown

Mathematics Dissertations

One of the most widely studied class of semifields are the generalized twisted fields defined by Albert in the 50s and 60s. The collineation groups of generalized twisted field planes have been completely described. In a series of papers Cordero and Figueroa studied semifields with an autotopism that acts transitively on one side of the autotopism triangle, equivalently the plane admits an autotopism which induces a permutation on a side of the autotopism triangle of order a p-primitive divisor of pr - 1. They showed that with some minor exceptions the plane is a generalized twisted field plane. These planes …

From Discrete To Continuous Models Of Cell Movement: An Application To Medical Implants, Alicia Prieto Langarica

Mathematics Dissertations

Mathematical modeling of cell movement is needed to aid in the deeper understanding of vital processes such as embryogenesis, angiogenesis, tumor metastasis, and immune reactions to foreign bodies. In this work, cell movement and growth in response to external stimulus and the interactions between cells and the stimulus are considered. In order to model the random nature of the movement, a discrete model is created to simulate cells moving in the presence of a growing and moving stimulus distribution. The model also includes the depletion of the stimulus under the presence of cells. The discrete model is then upscaled, based …

A Study On The Two Component Periodic Shallow Water Systems, Caixia Chen

Mathematics Dissertations

In this dissertation we study the generalized periodic two-component Camassa-Holm system and the generalized periodic two-component Dullin-Gottwald-Holm system, which can be derived from the Euler equation with nonzero constant vorticity in shallow water waves moving over a linear shear flow. The precise blow-up scenarios of strong solutions and several results of blow-up solutions with certain initial profiles are described in detail. The exact blow-up rates are also determined. Finally, the sufficient conditions for global solutions are established.

Market Reactions To Publicly Announced Privacy And Security Breaches Suffered By Companies Listed On The United States Stock Exchanges: A Comparative Empirical Investigation, Adolfo S. Coronado

Open Access Theses & Dissertations

Using a sample of security and privacy breaches the present research examines the comparative announcement impact between the two types of events. The first part of the dissertation analyzes the impact of publicly announced security and privacy breaches on abnormal stock returns, the change in firm risk, and abnormal trading volume are measured. The second part of the dissertation analyzes differential impact between security and privacy breaches on abnormal stock returns, the change in firm risk, and abnormal trading volume are measured.

Using a sample of 114 security (65) and privacy (49) breaches on average, security breaches resulted in more …

Lifting And Wavelets: A Factorization Method, Adrian Delgado

Open Access Theses & Dissertations

We begin with the concept of a discrete wavelet transformation. We begin with a scaling function satisfying a certain number of properties to be able to implement the wavelet transformation. We will then require translates of the scaling function to obey the same set of properties and this set will form what is called a Multiresolution Analysis. We then switch the ideas to the Fourier transform domain were we get equivalent results. However, instead of choosing a scaling function with coefficients to satisfy a set of properties, we will work backwards and construct a scaling function based on having a …

Optimal Placement Of Wind Turbines On Non-Flat Terrain Using Cluster Identification And Multi-Objective Genetic Algorithm, Carlos Alejandro Garcia Rosales

Open Access Theses & Dissertations

To date, wind power has become very popular to produce electricity due to climate change, greenhouse gases and the fossil fuels crisis. Although using wind turbine technology to produce electricity is very mature, industries are looking to achieve the best utilization of the wind energy in order to fulfill the electrical needs for cities at a very affordable cost. In this thesis, a method entitled Cluster Identification Algorithm (CIA) and an optimization approach called a Multi-Objective Genetic Algorithm (MOGA) are integrated and implemented to maximize wind power efficiency and wind power in wind farms and minimize cost caused by the …

Constrained Optimal Control For A Multi-Group Discrete Time Influenza Model, Paula Andrea Gonzalez Parra

Open Access Theses & Dissertations

During the last decades, mathematical epidemiological models have been used to understand the dynamics of infectious diseases and guide public health policy. In particular, several continuous models have been considered to study single in uenza outbreaks and the impact of dierent control policies. In this dissertation, a discrete time model is introduced in order to study optimal control strategies for in uenza transmission; since epidemiological data is collected on discrete units of time, a discrete formulation is more ecient. From a mathematical point of view, continuous time model are easier to analyze, however, the numerical solution of discrete-time models is …

Disparities In Park Availability, Features, And Characteristics By Social Determinants Of Health Within A U.S.-Mexico Border Urban Area, Amir Kamel

Open Access Theses & Dissertations

Background: Parks have been shown to be a key feature in the built environment that promote physical activity and positively influence health. However, a number of studies have highlighted that park availability, park features (e.g., park facilities, amenities, and aesthetic features), and park characteristics (e.g., quality/safety concerns of the park and surrounding neighborhood) are not equally distributed across neighborhoods in the U.S, specifically areas of low socioeconomic status and diverse racial/ethnic composition. The overall aim of this study was to examine and describe park availability, park features, and park characteristics, and determine their association with two social determinants of health …

Water Mass Balances For The Rio Grande/Bravo From Fort Quitman, Texas To Foster Ranch Near Langtry, Texas: An Assessment Of Factors, Ramiro Lujan

Open Access Theses & Dissertations

ABSTRACT

Water availability is declining in many regions of the planet, particularly in arid and semi-arid regions. Water bodies located in these regions, like the Rio Grande/Bravo at the U.S. - Mexico border, are subjected to high water demands. This research project makes an assessment of the spatial and temporal variability of elements intervening in the water mass balance for the section of the Rio Grande/Bravo between Fort Quitman and Langtry, Texas during the time period extending from January 1990 through December 2005. This document mentions the main Rio Grande/Bravo stakeholders from the U.S. and Mexico, and describes issues related …

A Survey Of Selected Pharmaceuticals And Personal Care Products In A Binational River And Their Effects On A Member Of Its Zooplankton Community, Plationus Patulus (Rotifera), Diana Angelica Martinez Gomez

Open Access Theses & Dissertations

The presence of 9 selected PPCPs (acetaminophen, caffeine, cotinine, codeine, fluoxetine, erythromycin, ciprofloxacin, sulfamethazine, and trimethoprim) was surveyed in water samples collected at four sites along the middle Rio Grande during two flow regimes (irrigation and non-irrigation). Water collection for PPCPs analyses were conducted from August 2010 through September 2011. Three of the sites were located upstream, in, and downstream of the El Paso, TX/Ciudad Juárez, MX metroplex. Site selection was based on their proximity to the metroplex and due to the fact that the Rio Grande in this region is an effluent receiver water system (IBWC, 2011). The fourth …

Evaluation Of A Cash Award Program For Water Conservation, Robert Moss

Open Access Theses & Dissertations

This document is the final report of a water conservation study funded by the U.S. Bureau of Reclamation and The University of Texas at El Paso with cooperation from El Paso Water Utilities. The study period was from September, 1997 through January, 2000.

Numerical Modeling Of Tectonics And Fault Activity Of Icy Satellites, John Olgin

Open Access Theses & Dissertations

Enceladus, one of the satellites of Saturn, exhibits evidence of recent fault activity, which may be due to gravitational fluctuations, or tidal stresses, generated by its orbit around Saturn. Recent Cassini spacecraft observations of Enceladus reveal water-ice plume activity at the south polar region, originating from locations that correlate with four geologically young, linear fracture-like features, named the "tiger stripes". It is the goal of this investigation to determine the ideal geophysical and geological factors (e.g., fault depths, frictional coefficients, ice layer thickness, ocean layer thickness, tidal stress sources) that support fault activity on Enceladus. The core of this work …

Analysis And Modeling Of Dust Event Data From El Paso, Texas, Nancy Ivette Rivera Rivera

Open Access Theses & Dissertations

Wind erosion is a dynamic physical process that leads to environmental degradation when strong winds blow on loose, dry, bare soils, creating dust events that can impact human health, visibility and air quality. Since 1932, more than two thousand dust event days were recorded at El Paso, averaging 25 per year. This research analyzes and models data on dust events in the El Paso/Juarez metropolitan area for better understanding of their effects. The meteorological characteristics of these events are analyzed for variables such as the frequency, visibility, and average wind speeds associated with convective and non-convective events. These variables are …

The Topology Of Statistical Convergence, Khdiga Kalifa Tabib

Open Access Theses & Dissertations

A sequence {xn} is said to be statistically convergent to ℓ provided that "almost all" of the values of {xn} are arbitrarily close to ℓ. One can also define what is meant by statistical limit point, statistical limit superior, statistical limit inferior of a sequence and so forth and thus create a theory of convergence that includes ordinary convergence. In this work we investigate all these concepts and prove some new results. We also introduce a topology defined by this new convergence which we call statistical topology. Then we prove that both the statistical topology and the regular topology are …

Effects Of Network Trace Sampling Methods On Privacy And Utility Metrics, Phillip A. Fazio, Keren Tan, David Kotz

Dartmouth Scholarship

Researchers choosing to share wireless-network traces with colleagues must first anonymize sensitive information, trading off the removal of information in the interest of identity protection and the preservation of useful data within the trace. While several metrics exist to quantify this privacy-utility tradeoff, they are often computationally expensive. Computing these metrics using a \emphsample\/ of the trace could potentially save precious time. In this paper, we examine several sampling methods to discover their effects on measurement of the privacy-utility tradeoff when anonymizing network traces. We tested the relative accuracy of several packet and flow-sampling methods on existing privacy and utility …

Characterizations Of Logistic Distribution Through Order Statistics With Independent Exponential Shifts, M. Ahsanullah, George Yanev, Constantin Onica

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Distributional properties of logistic order statistics subject to independent exponential one-sided and two-sided shifts are established. Utilizing these properties, we extend several known results and obtain new characterizations of the logistic distribution.

Integrable Models For Shallow Water With Energy Dependent Spectral Problems, Rossen Ivanov, Tony Lyons

Articles

We study the inverse problem for the so-called operators with energy depending potentials. In particular, we study spectral operators with quadratic dependence on the spectral parameter. The corresponding hierarchy of integrable equations includes the Kaup–Boussinesq equation. We formulate the inverse problem as a Riemann–Hilbert problem with a Z₂ reduction group. The soliton solutions are explicitly obtained.

Electric-Field-Induced Interfacial Instabilities Of A Soft Elastic Membrane Confined Between Viscous Layers, Mohar Dey, Dipankar Bandyopadhyay, Ashutosh Sharma, Shizhi Qian, Sang Woo Joo

Mechanical & Aerospace Engineering Faculty Publications

We explore the electric-field-induced interfacial instabilities of a trilayer composed of a thin elastic film confined between two viscous layers. A linear stability analysis (LSA) is performed to uncover the growth rate and length scale of the different unstable modes. Application of a normal external electric field on such a configuration can deform the two coupled elastic-viscous interfaces either by an in-phase bending or an antiphase squeezing mode. The bending mode has a long-wave nature, and is present even at a vanishingly small destabilizing field. In contrast, the squeezing mode has finite wave-number characteristics and originates only beyond a threshold …

Microfluidic Impedance Spectroscopy As A Tool For Quantitative Biology And Biotechnology, Ahmet C. Sabuncu, Jie Zhuang, Juergen F. Kolb, Ali Beskok

Mechanical & Aerospace Engineering Faculty Publications

A microfluidic device that is able to perform dielectric spectroscopy is developed. The device consists of a measurement chamber that is 250 μm thick and 750 μm radius. Around 1000 cells fit inside the chamber assuming average quantities for cell radius and volume fraction. This number is about 1000 folds lower than the capacity of conventional fixtures. A T-cell leukemia cell line Jurkat is tested using the microfluidic device. Measurements of deionized water and salt solutions are utilized to determine parasitic effects and geometric capacitance of the device. Physical models, including Maxwell-Wagner mixture and double shell models, are used to …

Numerical Methods For Fluid-Structure Interaction - A Review, Gene Hou, Jin Wang, Anita Layton

Mechanical & Aerospace Engineering Faculty Publications

The interactions between incompressible fluid flows and immersed structures are nonlinear multi-physics phenomena that have applications to a wide range of scientific and engineering disciplines. In this article, we review representative numerical-methods based on conforming and non-conforming meshes that are currently available for computing fluid-structure interaction problems, with an emphasis on some of the recent developments in the field. A goal is to categorize the selected methods and assess their accuracy and efficiency. We discuss challenges faced by researchers in this field, and we emphasize the importance of interdisciplinary effort for advancing the study in fluid-structure interactions

Implementation And Assessment Of A Virtual Reality Experiment In The Undergraduate Themo-Fluids Laboratory, Sushil Chaturvedi, Jaewan Yoon, Rick Mckenzie, Petros J. Katsioloudis, Hector M. Garcia, Shuo Ren

Mechanical & Aerospace Engineering Faculty Publications

Results are presented from an NSF supported project that is geared towards advancing the development and use of virtual reality (VR) laboratories, designed to emulate the learning environment of physical laboratories. As part of this project, an experiment in the undergraduate thermo-fluids laboratory course titled "Jet Impact Force" was transformed into a 3-D virtual reality experiment using the widely used MAYA R and VIRTOOLS R software. In order to facilitate students' interactions with the newly created 3-D interactive, immersive and stereoscopic virtual laboratory environment, the human computer interfaces (HCI) were programmed and incorporated in the simulation software. Two immersion levels …

Tackling Gravity Wave Confusion Noise With Template Optimizers, A. S. Stroeer, Matthew Benacquista

Physics and Astronomy Faculty Publications and Presentations

The Mock LISA Data Challenge 4.0 simulated the joint two-year recording of gravitational wave signals from mergers of spinning black holes, extreme mass ratio inspirals, Galactic white dwarf binaries, bursts from cosmic strings, and a stochastic background—all over LISA instrument noise. We analysed this data using a global multi-start box and bound optimization scheme, incorporating multi-dimensional Nelder Mead simplex 2 optimization. Our scheme identified 2658 binaries. Of these, 2246 were found to systematically decompose the power in a strong spinning black hole merger into a "white dwarf binary transform". The remaining 416 binaries were identified with a false alarm rate …

The Characterization Of Virgo Data And Its Impact On Gravitational-Wave Searches, J. Aasi, J. Abadie, Matthew Benacquista, R. Biswas, G. Cagnoli, Teviet Creighton, H. Daveloza, Mario C. Diaz, S. R. Morriss, Soma Mukherjee, M. E. Normandin, Volker Quetschke, Malik Rakhmanov, Joseph D. Romano, Robert Stone, A. S. Stroeer, Cristina V. Torres

Physics and Astronomy Faculty Publications and Presentations

Between 2007 and 2010 Virgo collected data in coincidence with the LIGO and GEO gravitational-wave (GW) detectors. These data have been searched for GWs emitted by cataclysmic phenomena in the universe, by non-axisymmetric rotating neutron stars or from a stochastic background in the frequency band of the detectors. The sensitivity of GW searches is limited by noise produced by the detector or its environment. It is therefore crucial to characterize the various noise sources in a GW detector. This paper reviews the Virgo detector noise sources, noise propagation, and conversion mechanisms which were identified in the three first Virgo observing …

Letter From The Editor, Ann Acheson

Maine Policy Review

No abstract provided.

Introduction, Linda Silka, Bridie Mcgreavy, Brittany Cline, Laura Lindenfeld

Maine Policy Review

Introduces special issue of Maine Policy Review focused on Maine's "Sustainability Solutions Initiative," an NSF/EPSCoR-funded project that brings together faculty from higher education institutions around the state to work with stakeholders on sustainability issues through the lens of sustainability science.

Sustainability: The Challenges And The Promise, George J. Mitchell

Maine Policy Review

Senator George J. Mitchell’s Margaret Chase Essay reflects on sustainable development. He discusses how teams of Maine faculty and students are working in partnerships across business, government and non-governmental organizations to seek solutions for a wide range of ecological and economic challenges.

Interview With Robert Kates, Pathfinder In Sustainability Science, Bridie Mcgreavy, Robert Kates

Maine Policy Review

In this interview, Robert Kates discusses the challenges of sustainability science in moving from what scientists know to actions that can provide solutions to pressing environmental and development problems. Kates notes that sustainability science has the dual mission of addressing core scientific and intellectual questions, while at the same time addressing development in particular places. He suggests that one of the key questions is how to address long-term trends and transition to a “better synthesis between environment and society.”

Advancing Science And Improving Quality Of Place: Linking Knowledge With Action In Maine’S Sustainability Solutions Initiative, Damon Hall, Linda Silka, Laura Lindenfeld

Maine Policy Review

The authors give an overview of how research carried out through Maine’s Sustainabilty Solutions Initiative (SSI) improves traditional models of science by providing a fuller picture of the interaction between social and ecological systems. They provide examples of university-community research partnerships, where there is a continuous communication and feedback process that identifies problems and develops projects with a solutions-oriented focus. SSI projects, they argue, “focus on issues that may make lasting improvements to Maine’s quality of place.”