Physical Sciences and Mathematics Commons^™

Synthesis, Structure, And Spectroscopic Properties Of Diphenyl Pyridine Amine Platinum (Ii) Complexes, Jacqueline Gamboa Varela^, Alejandro J. Metta-Magaña, Jose E. Núñez*

COURI Symposium Abstracts, Spring 2012

No abstract provided.

Electric Susceptibility For Strongly Magnetized Electron-Positron Plasma At Finite Temperature And Density, Paul L. Springsteen ^, Efrain J. Ferrer *, Angel Sanchez

COURI Symposium Abstracts, Spring 2012

We study the electric response of a relativistic electron-positron plasma at finite density and temperature in the presence of a strong magnetic field. The results are found by calculating the polarization tensor of such a system in the one-loop approximation. It was determined that a photon traveling through this medium acquires a Debye mass that depends on the magnitude of the magnetic field, temperature and chemical potential. We also found that the system electric susceptibility is anisotropic, with a component transverse to the magnetic field, which is that of vacuum, and a longitudinal component, which decreases with the temperature and …

Superspin Relaxation Times In Fe3o4 / Hexane Magnetic Fluids Measured By Frequency-Resolved Ac Susceptibility, Joshua L. Morris ^, Michael P. Eastman, Cristian E. Botez *

COURI Symposium Abstracts, Spring 2012

A properly formatted abstract has been uploaded below. The pasted version is here

Superspin relaxation times in Fe₃O₄ / hexane magnetic fluids measured by frequency-resolved ac susceptibility

Joshua Morris^ and Cristian E. Botez*

Department of Physics, University of Texas at El Paso, 500 W. University Avenue,

El Paso, TX 79968, U.S.A

Michael P. Eastman

Department of Chemistry, University of Texas at El Paso, 500 W. University Avenue,

El Paso, TX 79968, U.S.A

We have used frequency-resolved (100 Hz < f < 10,000 Hz) ac magnetic susceptibility measurements to directly determine the Néel and Brown relaxation times in 30-nm-size Fe₃O₄ / hexane magnetic fluids at temperatures between 200 and 300 K. Our data collected on both …

Geologic Mapping Of The South Tibetan Detachment System In Western Bhutan Using Aster Multispectral Data, Adam H. Nazarian ^, Jose M. Hurtado Jr.*

COURI Symposium Abstracts, Spring 2012

Remotely sensed data is a powerful tool for studying geology in areas where traditional field geology proves costly or difficult. This study focuses on geologic mapping of the South Tibetan Detachment System (STDS) in the area where Bhutan, India, and China meet. Having improved geologic maps is important as background information for better understanding the evolution and structure of the regional geology. Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER) multispectral imagery was used to differentiate the low-grade metamorphosed Tethyan Sedimentary Sequence (TSS) of the hanging wall from the mid- to high-grade metamorphosed Greater Himalayan Sequence (GHS) of the footwall. …

Synthesis And Theoretical Studies Of Pyridyl Fullerene Derivatives For Supramolecular Applications In Photovoltaic Systems, Robert Vina-Marrufo ^, Danisha M. Rivera-Nazario, Agustin Molina-Ontoria, Luis Echegoyen *

COURI Symposium Abstracts, Spring 2012

No abstract provided.

Simplicity Is Worse Than Theft: A Constraint-Based Explanation Of A Seemingly Counter-Intuitive Russian Saying, Martine Ceberio, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical situations, simplified models, models that enable us to gauge the quality of different decisions reasonably well, lead to far-from-optimal situations when used in searching for an optimal decision. There is even an appropriate Russian saying: simplicity is worse than theft. In this paper, we provide a mathematical explanation of this phenomenon.

Algorithmics Of Checking Whether A Mapping Is Injective, Surjective, And/Or Bijective, E. Cabral Balreira, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In many situations, we would like to check whether an algorithmically given mapping f:A --> B is injective, surjective, and/or bijective. These properties have a practical meaning: injectivity means that the events of the action f can be, in principle, reversed, while surjectivity means that every state b from the set B can appear as a result of the corresponding action. In this paper, we discuss when algorithms are possible for checking these properties.

Extending Java For Android Programming, Yoonsik Cheon

Departmental Technical Reports (CS)

Android is one of the most popular platforms for developing mobile applications. However, its framework relies on programming conventions and styles to implement framework-specific concepts like activities and intents, causing problems such as reliability, readability, understandability, and maintainability. We propose to extend Java to support Android framework concepts explicitly as built-in language features. Our extension called Android Java will allow Android programmers to express these concepts in a more reliable, natural, and succinct way.

Modal Intervals As A New Logical Interpretation Of The Usual Lattice Order Between Interval Truth Values, Francisco Zapata

Departmental Technical Reports (CS)

In the traditional fuzzy logic, we use numbers from the interval [0,1] to describe possible expert's degrees of belief in different statements. Comparing the resulting numbers is straightforward: if our degree of belief in a statement A is larger than our degree of belief in a statement B, this means that we have more confidence in the statement $A$ than in the statement B. It is known that to get a more adequate description of the expert's degree of belief, it is better to use not only numbers $a$ from the interval [0,1], but also subintervals [a1,a2] of this interval. …

Kinematic Spaces And De Vries Algebras: Towards Possible Physical Meaning Of De Vries Algebras, Olga Kosheleva, Francisco Zapata

Departmental Technical Reports (CS)

Traditionally, in physics, space-times are described by (pseudo-)Riemann spaces, i.e., by smooth manifolds with a tensor metric field. However, in several physically interesting situations smoothness is violated: near the Big Bang, at the black holes, and on the microlevel, when we take into account quantum effects. In all these situations, what remains is causality -- an ordering relation. To describe such situations, in the 1960s, geometers H. Busemann and R. Pimenov and physicists E. Kronheimer and R. Penrose developed a theory of kinematic spaces. Originally, kinematic spaces were formulated as topological ordered spaces, but it turned out that kinematic …

Image And Model Fusion: Unexpected Counterintuitive Behavior Of Traditional Statistical Techniques And Resulting Need For Expert Knowledge, Omar Ochoa, Aaron A. Velasco, Vladik Kreinovich

Departmental Technical Reports (CS)

In many real-life situations, we have different types of data. For example, in geosciences, we have seismic data, gravity data, magnetic data, etc. Ideally, we should jointly process all this data, but often, such a joint processing is not yet practically possible. In such situations, it is desirable to "fuse" models (images) corresponding to different types of data: e.g., to fuse an image corresponding to seismic data and an image corresponding to gravity data. At first glance, if we assume that all the approximation errors are independent and normally distributed, then we get a reasonably standard statistical problem which can …

Proton-Coupled Electron Transfer (Pcet) With Bimetallic Systems, Maripaz A. Calderon ^, Dino Villagran *

COURI Symposium Abstracts, Spring 2012

Electron-transfer (ET) is one of the simplest chemical events, yet, it is a vital process for chemical reactivity. Proton-coupled electron transfer (PCET) is the concerted transfer of protons and electrons which is fundamental in chemical and biological systems and processes in electrochemistry, photosynthesis, and enzymatic activity. Similarly, mixed-valence (MV) systems are pervasive in nature and provide a platform for multiple electron transfers systems in nature. While both fields have been studied extensively, little work has been done on the intersection of the two. This project explores the elegant use of MV bimetallic systems through hydrogen bonded networks. A variety compounds …

The Application Of Fuzzy Granular Computing For The Analysis Of Human Dynamic Behavior In 3d Space, Murad Mohammad Alaqtash

Open Access Theses & Dissertations

Human dynamic behavior in space is very complex in that it involves many physical, perceptual and motor aspects. It is tied together at a sensory level by linkages between vestibular, visual and somatosensory information that develop through experience of inertial and gravitational reaction forces. Coordinated movement emerges from the interplay among descending output from the central nervous system, sensory input from the body and environment, muscle dynamics, and the emergent dynamics of the whole neuromusculoskeletal system.

There have been many attempts to directly capture the activities of the neuronal system in human locomotion without the ability to clarify how the …

Applications Of Density Functional Theory In Materials Science And Engineering, Manuel Alvarado

Open Access Theses & Dissertations

Density Functional Theory (DFT) is a powerful tool that can be used to model various systems in materials science. Our research applies DFT to two problems of interest. First, an organic/inorganic complex dye system known as a Mayan pigment is modeled to determine chemical binding sites, verifying each model with physical data such as UV/Vis spectra. Preliminary studies on palygorskite-based mayan pigments (mayacrom blue, mayacrom purple) show excellent agreement with experimental studies when using a dimer dye geometry binding with tetrahedrally-coordinated aluminum impurity sites in palygorksite. This approach is applied to a sepiolite-based organic/inorganic dye system using thioindigo attached to …

Study Of Volatility Structures In Geophysics And Finance Using Garch Models, Francis Biney

Open Access Theses & Dissertations

This work investigates the underlying volatility processes in earthquake series, explosive series, high frequency (tick) data and financial indices. Furthermore it examines the applicability of a range of GARCH specifications for modeling volatility of these series in order to identify similarities and differences in the volatility structures. The GARCH

variants considered include the basic GARCH, IGARCH, ARFIMA (0,d,0)-GARCH and FIGARCH specifications. In all the applications the methodology provides insight into features of these series volatility.

Seismic Reflection Study Of The East Potrillo Fault, Southwestern Dona Ana County, New Mexico, Shane Alan Carley

Open Access Theses & Dissertations

The East Potrillo Mountains are located just north of the U.S.-Mexico border in southwestern Dona Ana County, New Mexico. Laramide and Rio Grande rift deformation has formed low-angle and high-angle Tertiary normal faults that are exposed in the area. Along the east flank of the range is the East Potrillo Fault identified on the surface as a north-striking scarp. Fault scarps associated with the East Potrillo Fault have been dated using slope degradation models and they range between 56 ka and 377 ka in age. Offset of geomorphic surfaces interpreted to be tectonic terraces records at least four earthquakes over …

High-Order Central Finite-Volume Schemes For Atmospheric Modeling, Kiran Kumar Katta

Open Access Theses & Dissertations

Atmospheric numerical modeling has been going through drastic changes over the past decade, mainly to utilize the massive computing capability of the petascale systems. This obliges the modelers to develop grid systems and numerical algorithms that facilitate exceptional level of scalability on these systems. The numerical algorithms that can address these challenges should have the local properties such as the high on-processor operation count and minimum parallel communication i.e., high parallel efficiency. They should also satisfy the following properties such as inherent local and global conservation, high-order accuracy, geometric flexibility, non-oscillatory advection and positivity preservation properties. The goal of this …

Evaluating Hydrocarbon Source Rock For Unconventional Shale Oil Play From Seismic And Well Log Data; Kingak Shale, North Slope, Alaska, Sarah Elisabeth Leedberg

Open Access Theses & Dissertations

It has been proposed that Acoustic impedance (AI) responses can be used to estimate total organic carbon (TOC) within thick, clay rich shale. The purpose of this work is to evaluate the effectiveness of the AI inversion technique, and establish a methodology that can be applied to other basins. The Kingak Formation (lower Jurassic to early Cretaceous), located on the North Slope of Alaska, has been extensively evaluated for its unconventional potential. The Kingak is shale and is known to have greater than 30 percent clay. Because clay has ductile properties it makes it difficult to stimulate a well through …

Constraints On The Structure Of The Border Ranges Fault System, South-Central Alaska From Integrated 3d Inversion Of Gravity/Magnetic Data, Niti Mankhemthong

Open Access Theses & Dissertations

I use updated gravity data, available aeromagnetic data, and other geophysical information as constraints to develop 2D and 3D structural models of density and magnetic susceptibility to better locate and determine the shape of the Border Ranges fault system (BRFS), the Border Range ultramafic and mafic assemblages and other forearc-arc boundary structures in south-central Alaska, that have previously been studied in only limited detail. There are three geophysical research projects that form the chapters of the dissertation. First, I estimated near-surface density variations in the central Kenai Peninsula based on the adaptation of the Nettleton (1939)-Parasnis (1952) method using Tarantola …

Constrained Optimization Schemes For Geophysical Inversion Of Seismic Data, Uram Anibal Sosa Aguirre

Open Access Theses & Dissertations

Many experimental techniques in geophysics advance the understanding of Earth processes by estimating and interpreting Earth structure (e.g., velocity and/or density structure). These techniques use dierent types of geophysical data which can be collected and analyzed separately, sometimes resulting in inconsistent models of the Earth depending on data quality, methods and assumptions made. This dissertation presents two approaches for geophysical inversion of seismic data based on constrained optimization. In one approach we expand a one dimensional (1-D) joint inversion least-squares (LSQ) algorithm by introducing a constrained optimization methodology. Then we use the 1-D inversion results to produce 3-D Earth velocity …

On The Selection Of Prosodic Features For Language Modeling, Alejandro Vega

Open Access Theses & Dissertations

Previous studies show that immediate and long range prosodic context provide benecial information when applied to a language model. However, the fact that some features provide more information to the prediction task should be considered. If the information contribution of each feature can be determined, then a well-crafted feature set can be built to improve the performance of a language model. In this study, I measure the contribution of dierent prosodic features to a baseline trigram model. Using this information, it should be possible to build a language model that uses the most informative resources and ultimately performs better than …

Analysis Of Intermittence And Log-Periodicity Of Foreign Exchange Rates Near A Crash, Arturo Casillas

Open Access Theses & Dissertations

Many believe that financial indices near a crash exhibit a type of critical point characterized by log-periodic signatures. Models have been developed based on these ideas in an attempt to mathematically characterize financial data about to crash. Few of these models consider the property of intermittency. Intermittency is a concept borrowed from fluid dynamics that essentially implies that a system alternates between a stable, or predictable, state and unstable state. One model that attempts to characterize crashes incorporates intermittency in the form of log-stationary intervals. It models the asset price as a step function that follows an underlying power law. …

Implications Of Decade Time Scale Arctic Plant Community Change On Ecosystem Function, Mark Jason Lara

Open Access Theses & Dissertations

Almost half the global soil organic carbon pool is found in northern high latitudes. The majority of this soil carbon is stored in a greenhouse inert state within permafrost. As pronounced warming of high northern latitudes ensues, there is a strong likelihood that this substantial soil organic carbon pool will be mobilized to the atmosphere where it is likely to positively enhance greenhouse warming. Modeling studies suggest this positive feedback could alter future climate states of the Arctic and the globe, and affect how humans may need to adapt to climate change. Accordingly, understanding the patterns and controls and the …

Ontologies For Scientific Data Transformation, Leonardo Salayandia

Open Access Theses & Dissertations

A common task for scientists is to collect data and apply algorithms to process the data. Scientists who aim to use data collected or processed by other scientists must be able to determine the applicability of the data. Supporting a scientist's capability to identify and reason about data can be achieved by associating the data with metadata about the conditions under which the data was collected and how it was processed, i.e., its provenance. This dissertation presents the Workflow-Driven Ontology (WDO) framework for representing formal knowledge about data with respect to how it is collected and transformed. Formally represented knowledge …

High Pressure Synchrotron X-Ray Diffraction Studies Of Superprotonic Transitions In Phosphate Based Solid Acids, Juan Daniel Hermosillo

Open Access Theses & Dissertations

Certain phosphate based solid acids, such as CsH2PO4 and RbH2PO4, have been shown to exhibit an abrupt, several-order-of-magnitude increase in their proton conductivity when heated above a temperature threshold. This so called superprotonic behavior allows the above-mentioned materials to function as fuel cell electrolytes at temperatures between 150C and 300C, a remarkable application that attracted significant interest especially from the automobile industry. Yet, the microscopic structures and dynamic mechanisms responsible for this behavior are not fully understood. In fact, until very recently, the very nature of the superprotonic behavior has been debate, with some groups attributing the steep proton enhancement …

New Methods For The Discovery And Characterization Of Lunar Lava Tubes Using Lunar Reconnaissance Orbiter Data, Jonathan Arthur Meyer

Open Access Theses & Dissertations

Lava tubes have the potential to serve as a sustainable solution to long-term lunar habitation by providing protection from radiation and micrometeorite bombardment while potentially providing resources in the form of trapped water ice. They also pose compelling science targets in their own right. While the potential benefits of utilizing lunar lava tubes is clear, their discovery is less straightforward. Formation processes for lava tubes do not always result in a surface expression, making their discovery using remotely sensed imagery difficult. Furthermore, there is the potential for lava tubes to be covered by secondary lava flows, impact ejecta, or other …

The Hammer-And-Nail Phenomenon In Mathematics Education, Kien H. Lim

Departmental Papers (Math)

"For a person with a hammer, everything looks like a nail" is a proverb that can be used to highlight the phenomenon that students tend to rely on familiar ideas as opposed to taking time to think about and analyse a problem. Presented in this theoretical paper is the usefulness of the hammer-and-nail metaphor, other related theoretical constructs, pedagogical causes of student impulsive behaviours, and pedagogical suggestions for addressing them.

An Immersed Interface Method For A 1d Poroelasticity Problem With Discontinuous Coefficients, Maranda Lee Bean

Open Access Theses & Dissertations

Poroelastic models deal with the coupling of changes in stress and fluid pressure in some porous medium. For physical reasons, some of the coefficients used in the models may have discontinuities. This project focuses on applying the immersed interface method to the one dimensional Biot model, in order to handle these discontinuities. This method is applied on a staggered grid. Using the immersed interface method allows us to alter only a small number of irregular grid points surrounding a discontinuity. For most of the grid points, a standard finite difference method is used. However at the irregular grid points, the …

Fault Tolerance: Validating A Mathematical Model Via A Case Study Of Raxml, An Hpc Community Code, Bidisha Chakraborty

Open Access Theses & Dissertations

Researchers have mentioned that the three most difficult and growing problems in the future of high-performance computing will be avoiding, coping and recovering from failures. As the scale of computing increases, the Mean Time to Failure (MTTF) of the entire system decreases and, therefore, system resilience and fault tolerance techniques become mandatory. One of the most commonly used fault tolerance schemes is checkpoint/restart, however, it has been predicted that the current checkpoint/restart approach is not scalable. Thus, current research seeks to find scalable fault tolerance techniques as well as to extend the scalability of checkpoint/restart.

The periodicity of the checkpointing …

Investigation Of A Water Desalination Method Via A Humidification-Dehumidification Process Using Hvac Technology, Juan Antonio Cornejo

Open Access Theses & Dissertations

Potable water is becoming a scarce resource in many arid regions of the world. An experimental unit was designed and constructed to examine and characterize the production capabilities of a humidification-dehumidification (HDH) desalination process. An HDH cycle offers a viable, technologically light, alternative for producing fresh water from brackish water because the low relative humidity air is infused with water vapor through evaporation by means of conventional heating, ventilation and air conditioning (HVAC) components. The evaporation process effectively separates salts and suspended solids from the brackish feed-water. Desalinated water is subsequently recovered by extracting the water vapor from the moist …