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Full-Text Articles in Physical Sciences and Mathematics

Software Development For A Three-Dimensional Gravity Inversion And Application To Study Of The Border Ranges Fault System, South-Central Alaska, Rolando Cardenas Jan 2011

Software Development For A Three-Dimensional Gravity Inversion And Application To Study Of The Border Ranges Fault System, South-Central Alaska, Rolando Cardenas

Open Access Theses & Dissertations

The Border Ranges Fault System (BRFS) bounds the Cook Inlet and Susitna Basins, an important petroleum province within south-central Alaska. A primary goal in the research is to test several plausible models of structure along the Border Ranges Fault System using a novel three-dimensional inversion utilizing gravity and magnetic data, constrained with other geophysical, borehole and surface geological information. This research involves the development of inversion modeling software using a Borland C++ compiler as part of the Rapid Application Development (RAD) Studio. The novel inversion approach directly models known geology, and "a priori" uncertainties on the geologic model to allow …


Cognitive Constructs In Linear Algebra; Metaphors, Metonymies, Modes, Ruben Carrizales Jan 2011

Cognitive Constructs In Linear Algebra; Metaphors, Metonymies, Modes, Ruben Carrizales

Open Access Theses & Dissertations

Analysis focused on the presence of different thinking modes, metonymies, and metaphors found on the interview responses to questions related to linear independence, span, and spanning sets of three students, A12, A22 and C3, taking their first linear algebra course at the college level. Findings provide insight into how first year linear algebra students move from one thinking mode to another, and the kind of metonymies and metaphors are used to construct new knowledge. The main purpose of this research was to discover and analyze the presence of the different modes of thinking and metonymy/metaphors- in the reasoning of these …


The East Jhomolari Fault System And The Timing Of East-West Extension In Northwest Bhutan, John Matthew Cannon Jan 2011

The East Jhomolari Fault System And The Timing Of East-West Extension In Northwest Bhutan, John Matthew Cannon

Open Access Theses & Dissertations

This investigation documents a little known, regionally significant, high angle, southeast dipping, system of normal faults in northwest Bhutan, the East Jhomolari Fault System (EJFS). The EJFS trends parallel to the Yadong Gulu rift (YG) and can be traced from Mt. Jhomolari to the northern border with Tibet. This fault zone has been demonstrably active since the last glacial maximum and there is geomorphic evidence of Holocene activity on some fault segments. The structurally lowest EJFS fault, the Lingshi fault appears on some published maps, but the full geographic extent, displacement, onset of faulting, and most recent activity have not …


Experimental And Numerical Investigation Of The Effect Of Fuel Composition On Flame Stability On A Gas Turbine Combustor, Gilberto Corona Jan 2011

Experimental And Numerical Investigation Of The Effect Of Fuel Composition On Flame Stability On A Gas Turbine Combustor, Gilberto Corona

Open Access Theses & Dissertations

Gas turbines are used for power generation and aviation all over the world. Fossil fuels remain the main source of energy for the operation of gas turbines but the recent increase in environmental awareness has influenced government agencies to impose stringent limits on pollutant emissions from power generation plants. Pollutant emissions control is one of the major challenges for gas turbine designers. In this study, experimental methods and computational fluid dynamics (CFD) technologies are used to study the problems that arise when coal derived fuels are used in Gas Turbine Combustors.

Gas turbine designers need both experimental data and combustion …


Influence Of Orography On The Weather Patterns And Water Availability Of A Topographically Complex Chihuahuan Desert Region, Fernanda De La Cerda Camargo Jan 2011

Influence Of Orography On The Weather Patterns And Water Availability Of A Topographically Complex Chihuahuan Desert Region, Fernanda De La Cerda Camargo

Open Access Theses & Dissertations

Arid and semi-arid ecosystems cover a large extent of the planet's land surface and are highly susceptible to/and dependent on resource availability patterns, especially precipitation. Topography affects large scale weather patterns and redistributes precipitation which creates a variety of microclimates in complex landscapes; how these patterns are modified, however, is still not fully understood. Climate change models for arid and semi-arid ecosystems predict a change towards more extreme precipitation events; understanding the mechanisms involved in redistributing precipitation is crucial for the protection of these areas. Indio Mountains Research Station (IMRS) is located in the northern Chihuahuan Desert and seems to …


Aerosol Characterizaton In El Paso-Juarez Airshed Using Optical Methods, Angel E. Esparza Jan 2011

Aerosol Characterizaton In El Paso-Juarez Airshed Using Optical Methods, Angel E. Esparza

Open Access Theses & Dissertations

The assessment and characterization of atmospheric aerosols and their optical properties are of great significance for several applications such as air pollution studies, atmospheric visibility, remote sensing of the atmosphere, and impacts on climate change. Decades ago, the interest in atmospheric aerosols was primarily for visibility impairment problems; however, recently interest has intensified with efforts to quantify the optical properties of aerosols, especially because of the uncertainties surrounding the role of aerosols in climate change. The main objective of the optical characterization of aerosols is to understand their properties. These properties are determined by the aerosols' chemical composition, size, shape …


A Proposed Epithermal Model For The High Grade District, California, Michael Nicholas Feinstein Jan 2011

A Proposed Epithermal Model For The High Grade District, California, Michael Nicholas Feinstein

Open Access Theses & Dissertations

A historic gold mining district in northeastern California has not been incorporated into the global knowledge base for precious metal vein deposits. This study collected various data types which are important characteristics in the classification and understanding of vein deposits. The High Grade District (HGD) is a gold mining site located in the northeast corner of Modoc County, California, in the Warner Mountains. The Warner Mountains are composed of Tertiary eruptive centers, cropping out between valleys formed through extensional tectonics. Mineralization of the HGD displays abundant silicification, adularia, and gold; these characteristics are sufficient to classify mineralization as low-sulfidation epithermal …


Specification Of Data Properties To Identify Anomalies In Scientific Sensor Data, Irbis Gallegos Jan 2011

Specification Of Data Properties To Identify Anomalies In Scientific Sensor Data, Irbis Gallegos

Open Access Theses & Dissertations

Environmental scientists use advanced sensor technology such as meteorological towers, wireless sensor networks and robotic trams equipped with sensors to perform data collection at remote research sites. Because the amount of environmental sensor data acquired by such instruments is increasing, the ability to evaluate the accuracy of the data at collection time and to check that the instrumentation is operating correctly become critical in order to not lose valuable time and information. The goal of the research is to define a solution, based on software-engineering techniques, to support the scientist's ability to specify data properties that can identify anomalies in …


A Reduced Order Parameter Estimation Technique Using Orthonormal Wavelets, Miguel Hernandez Iv Jan 2011

A Reduced Order Parameter Estimation Technique Using Orthonormal Wavelets, Miguel Hernandez Iv

Open Access Theses & Dissertations

In this work we introduce methods for model order reduction using orthonormal wavelets. Specifically, we propose techniques and algorithms for wavelet-based reduced order parameter estimation using orthonormal wavelets for solving nonlinear least squares problems. Approaches for parameter reduction using the one dimensional and two dimensional wavelet transforms are presented using multiple levels of decomposition.

The performance of wavelet-based reduced order parameter estimation is tested using a suite of orthonormal wavelets on a groundwater hydraulics model provided by the U.S. Army Corps of Engineers. Using the hydraulics model, the goal is to find a least-squares solution of the permeability field given …


Development Of A Low-Cost Network Of Webcams For Monitoring Plant Phenology In A Chihuahuan Desert Shrubland, Libia Gonzalez Jan 2011

Development Of A Low-Cost Network Of Webcams For Monitoring Plant Phenology In A Chihuahuan Desert Shrubland, Libia Gonzalez

Open Access Theses & Dissertations

Phenology is the study of the timing of natural events such as the schedule of plant life-cycle events like bud burst, flowering, seed set and senescence. Many factors control plant phenological dynamics including climate. As such, phenology has been shown in published literature to be one of the best biological indicators of climate variability and change. Recent advantages in digital photography and digital image processing have opened new opportunities for inexpensive, repeatable and automated capture of plant and landscape phenological dynamics. This technology, however, remains poorly studied in terms of its capacity to depict the development of different plant phenophases, …


Estimating Statistical Characteristics Under Interval Uncertainty And Constraints: Mean, Variance, Covariance, And Correlation, Ali Jalal-Kamali Jan 2011

Estimating Statistical Characteristics Under Interval Uncertainty And Constraints: Mean, Variance, Covariance, And Correlation, Ali Jalal-Kamali

Open Access Theses & Dissertations

In many practical situations, we have a sample of objects of a given type. When we measure the values of a certain quantity x for these objects, we get a sequence of values x1, . . . , xn. When the sample is large enough, then the arithmetic mean E of the values xi is a good approximation for the average value of this quantity for all the objects from this class. Other expressions provide a good approximation to statistical characteristics such as variance, covariance, and correlation.

The values xi come from measurements, and measurement is never absolutely accurate.

Often, …


Investigation On Flame Characteristics Of Oxy-Fuel Combustion, Md R. Islam Jan 2011

Investigation On Flame Characteristics Of Oxy-Fuel Combustion, Md R. Islam

Open Access Theses & Dissertations

Oxy-fuel combustion is currently being considered by the U.S Department of Energy as a promising technology for efficient carbon capture. This technology could substantially reduce NOx and CO2 emissions. In addition, the implementation of oxy-fuel combustion technology in a power generation system could potentially reduce negative environmental impacts of fossil fuel use. It also encourages the use of reliable and domestic energy sources. The U.S. Department of Energy has made efforts to investigate the performance of a CO2 and H2O diluted oxy-fuel combustion system in a high-pressure combustor. In an effort to better understand and characterize the fundamental flame characteristics …


Gamma And Generalized Gamma Distributions, Victor Hugo Jiménez Nava Jan 2011

Gamma And Generalized Gamma Distributions, Victor Hugo Jiménez Nava

Open Access Theses & Dissertations

We present the Generalized Gamma Distribution, study its properties and derive the estimators of the parameters. This distribution includes many standard forms, like: Gamma, Exponential, Weibull, Half Normal and others. Sum and ratios of independent generalized gamma lead to intractable forms. However approximation works well. In particular two-moment gamma and three moment normal approximations are shown to approximate the sum of k independent gamma as well as generalized gamma distributions.


Computational Methods Of Hidden Markov Models With Respect To Cpg Island Prediction In Dna Sequences, Roberto Angel Ortega Jan 2011

Computational Methods Of Hidden Markov Models With Respect To Cpg Island Prediction In Dna Sequences, Roberto Angel Ortega

Open Access Theses & Dissertations

Hidden Markov models (HMM's) are a specific case of Markov models where, contrary to Markov chains, the observer is unaware of what state the model was in when the symbol is observed. Like Markov chains, HMM's assume that the future state of a sequence is dependent only on the current state of the sequence. The parameters associated with HMM's are transition and emission probabilities, where transition probabilities are associated with the probability of transitioning from one state to another, and emission probabilities are the probabilities associated with observing a symbol given it came from a specific state.

The structure of …


An Integrated Geological And Geophysical Study Of The Fresh And Brackish Water Boundary In The Hueco Bolson, West Texas, Sandy Stephanie Marrufo Jan 2011

An Integrated Geological And Geophysical Study Of The Fresh And Brackish Water Boundary In The Hueco Bolson, West Texas, Sandy Stephanie Marrufo

Open Access Theses & Dissertations

The Hueco Bolson in West Texas is located in the Rio Grande rift basin and provides water to El Paso County, Texas and Juarez, Mexico. El Paso Water Utilities (EPWU) drilled many wells up to 1000 ft (305) m into this aquifer, which provide 40% of El Paso's water supply. Stratigraphy and sedimentation in active extensional basins have received little study because they are usually buried and this research helped document these processes. The study area within the West Texas region of the Hueco Bolson Aquifer (HBA) lies within a transition zone between the fresh and brackish water sections of …


Gemini Metallo-Surfactants: Chemical And Physical Properties, Erich Ivan Valenzuela Jan 2011

Gemini Metallo-Surfactants: Chemical And Physical Properties, Erich Ivan Valenzuela

Open Access Theses & Dissertations

Gemini surfactants are amphiphilic molecules that consist of two surfactant molecules chemically joined together by a spacer group. These molecules tend to self‐assemble into vesicles at much lower concentrations than traditional surfactants and have found many applications in catalysis, adsorption applications, drug‐delivery, nanoscale technology, and biotechnology. In this thesis, the synthesis, characterization and physical properties of a new type of Gemini surfactant derived from dinuclear Cu(II) metal complexes is presented. We call these molecules Gemini Metal‐Organic Surfactants (GMOs).

Three newly developed new GMOs (compounds 1‐3) are composed of Cu(II) ions ligated to a lipid‐functionalized triamine group and the metals are …


Principles Of Thomas Pynchon's Literary Realities, Ira Anthony Walker Jan 2011

Principles Of Thomas Pynchon's Literary Realities, Ira Anthony Walker

Open Access Theses & Dissertations

Thomas Pynchon's literature is unique in subject and style. Postmodern by definition, Pynchon illustrates physics as a societal metaphor; Guy Debord's text The Society of the Spectacle suggests that these societal, literary, metaphors constitute and/or lead to a Spectacle. Through the analysis of an unpublished text: Minstrel Island, an early written short story: "Entropy," and a short novel: The Crying of Lot 49 the reader is capable of seeing a developing theme of physics as metaphor constituting multiple Spectacles. The narrative devices offered by Thomas Pynchon become Spectacular in nature and reflect the characteristics and environment of the tumultuous 1960s …


Patterns And Controls Of Erosion Along The Barrow Environmental Observatory Coastline, Northern Alaska, Adrian Aguirre Jan 2011

Patterns And Controls Of Erosion Along The Barrow Environmental Observatory Coastline, Northern Alaska, Adrian Aguirre

Open Access Theses & Dissertations

With pronounced arctic warming that is linked to loss of sea ice, sea level rise, and land cover change, over the coming decades arctic coastal regions are likely to undergo amongst the most dramatic changes of any ecosystem on Earth. This study used foot surveys and a Differential Global Positioning System (DGPS) to document at a high spatial (horizontal and vertical) resolution, the spatiotemporal dynamics of the eroding bluff along the coastline of the Barrow Environmental Observatory between 2003 and 2009. The coastline consists of an eroding bluff bordered by a shallow muddy lagoon. The coast is protected from strong …


Incorporating Sustainability Into Urban Infrastructures: The Tension Between Bio-Cultural Aspects And Environmental Considerations, Shane Epting Jan 2011

Incorporating Sustainability Into Urban Infrastructures: The Tension Between Bio-Cultural Aspects And Environmental Considerations, Shane Epting

Open Access Theses & Dissertations

The following arguments focus on how to think about sustainability as it relates to technology and the non-human world within an anthropocentric framework. We end up with a picture showing that humankind needs to change the ways in which we look at anthropocentric concerns. Secondly, the discussion that leads up to the final picture details the urgency that guides the thinking behind the implementation of sustainability. Because, as the West learns to live in an entirely new sense that is consistent with holding humankind's desire for existence as a permanent situation, one finds that this notion must be paramount for …


Comparison Of Two Environmental Health Education Methods To Reduce Exposure To Residential Pesticides In Hispanic, Patricia M. Juarez-Carrillo Jan 2011

Comparison Of Two Environmental Health Education Methods To Reduce Exposure To Residential Pesticides In Hispanic, Patricia M. Juarez-Carrillo

Open Access Theses & Dissertations

ABSTRACT

Exposure to pesticides is associated with adverse health outcomes including poisonings, short-term signs and symptoms, and long-term adverse health outcomes including developmental and cognitive impairments, certain types of cancer, and damages to the endocrine, nervous, and reproductive systems. This study tested two educational methods aimed to help Hispanic, Spanish-speaking mothers living in the U.S.-México border make informed decisions about pesticides applied in their homes. 230 women were randomly allocated to a) a small group talk, b) a graphic booklet, or c) a control group. The outcomes were the knowledge level about the risks of pesticides and the pest prevention …


Assessing Measurement Invariance In The Presence Of Testlets, Luis Andres Alvarado Jan 2011

Assessing Measurement Invariance In The Presence Of Testlets, Luis Andres Alvarado

Open Access Theses & Dissertations

Dealing with measurement invariance has been an issue of concern in confirmatory factor analysis for many years. It is important to establish measurement invariance across groups so that instruments may be validly used in multiple groups for comparison of the mean or summative scores. Throughout the years, many studies have considered testing for measurement invariance in factor models. However, there have been no studies that assess measurement invariance when so-called testlets should be modeled in the factor analytic model. Testlets add nuisance covariation to the model which can interfere when trying to detect measurement invariance. In the past, models have …


Combustion Of Lunar Regolith Mixed With Energetic Additives: Thermodynamic Calculations And Experimental Studies, Francisco Alvarez Jan 2011

Combustion Of Lunar Regolith Mixed With Energetic Additives: Thermodynamic Calculations And Experimental Studies, Francisco Alvarez

Open Access Theses & Dissertations

The future of space exploration will require longer missions in order to better understand the conditions of near-Earth celestial objects, like the Moon or Mars. Future space missions will require the development of goods, such as propulsion fuel and structural materials, produced using the extraterrestrial resources available. The area that develops these technologies is called In-Situ Resource Utilization (ISRU). ISRU allows reducing the payload, and as a consequence reduces the energy consumption and cost of space travel. The production of structural materials on the Moon can be accomplished using Self-Propagating High-Temperature Synthesis (SHS). This work describes the combination of ISRU …


Adaptation Of Low Impact Design To The Desert Southwest, Abubaker Ali Alamailes Jan 2011

Adaptation Of Low Impact Design To The Desert Southwest, Abubaker Ali Alamailes

Open Access Theses & Dissertations

A low Impact Development (LID) practices were used to design an Integrated Management Practices (IMP) system for a residential lot .The design was adapted to the Desert Southwest region based on twenty years of climate data including precipitation and temperature for three representative cities: El Paso, TX, Albuquerque, NM, and Phoenix, AZ. In order to capture stormwater runoff close to its source and to provide as much stored water as possible for plants, LID practices including bioretention cells and vegetated swales were applied throughout the lawn. The purpose of the design is to maintain the pre-development hydrologic characteristics of the …


Implications Of Surface Runoff Recharge In Semi-Arid Regions On Groundwater Sustainability, Omar M. Al-Qudah Jan 2011

Implications Of Surface Runoff Recharge In Semi-Arid Regions On Groundwater Sustainability, Omar M. Al-Qudah

Open Access Theses & Dissertations

Amargosa Desert, Nevada regional groundwater studies show that the surface runoff infiltration occurring in the arroyos following runoff producing storms, and this infiltration is considered to be a major source of groundwater recharge. Groundwater infiltration through alluvium was investigated in the Amargosa Desert using borehole drill cuttings, groundwater chemistry, and applying a novel method for collecting runoff water. The sampling process included sediment, precipitation, and runoff water. In total, 176 runoff, 182 sediment, and 45 precipitation samples were collected between January, 2009 and January, 2011.Water chemistry, chloride concentrations, and stable isotopes of water collected from specially designed runoff samplers, placed …


Nummulites Biofabrics As Tool For Quality Evaluation Of The Eocene Jdeir Formation Reservoirs Nw Offshore, Libya, Abdusalam Ali Agail Jan 2011

Nummulites Biofabrics As Tool For Quality Evaluation Of The Eocene Jdeir Formation Reservoirs Nw Offshore, Libya, Abdusalam Ali Agail

Open Access Theses & Dissertations

The southern Tethys margin constitutes an important hydrocarbon reservoir. It is formed mainly of Nummulite rich facies of the Jdeir Formation deposited during the Eocene epoch (Late Ypresian age) in the giant El-Bouri oil field-Sabratah Basin-NW Libya. Deposits of the Jdeir Formation directly overlay the Jirani dolomite and Bilal Formation, and unconformably underlay the Tellil Group and Ghallil Formation.

Nummulite accumulations are good indicators for hydrocarbon studies and they have been targets for numerous studies around the world. Nummulite "Large foraminifera" tests are usually identified by two forms: A-form and B-form. Previous studies have highlighted many different aspects of foraminifers …


Accumulation, Speciation, And Distribution Of Metal(Loids) In Plants: Applications Of Synchrotron Techniques In Environmental Sciences, Hiram Castillo-Michel Jan 2011

Accumulation, Speciation, And Distribution Of Metal(Loids) In Plants: Applications Of Synchrotron Techniques In Environmental Sciences, Hiram Castillo-Michel

Open Access Theses & Dissertations

In the last two decades, synchrotron based techniques have gained popularity and been increasingly used in environmental sciences. The present dissertation has relied significantly in the use of synchrotron based techniques to study the speciation, coordination, and distribution of toxic metal(loids) in plants. This study included three plant species: Parkinsonia florida, Prosopis juliflora, and Zea mays. P. florida is a plant species native to the semi-desert regions of North America. The cultivation characteristics of this shrub/tree suggest that it could be used for phytoremediation purposes in semiarid regions. P. florida plants were tested for their capacity to remove arsenic (As) …


Prediction Of Ribonucleic Acid Secondary Structures Using A Heuristic Backtracking Search, Christopher Roman Cuellar Jan 2011

Prediction Of Ribonucleic Acid Secondary Structures Using A Heuristic Backtracking Search, Christopher Roman Cuellar

Open Access Theses & Dissertations

Ribonucleic acid (RNA) is essential for all forms of life. RNA is made up of a large chain of nucleotide bases: Guanine (G), Uracil (U), Cytosine (C), and Adenine (A). An RNA strand can fold on itself to allow G-C, A-U, and G-U bases to form hydrogen bonds, this is known as a secondary structure. Knowing the secondary structure of an RNA chain is very important because it will allow researchers to better understand its specific functions. RNA will create secondary structures that tend to minimize their free energy. RNA secondary structure prediction is the attempt to predict physical folding …


A Characterization Of Directly Ordered Subspaces Of R^N, Jennifer Del Valle Jan 2011

A Characterization Of Directly Ordered Subspaces Of R^N, Jennifer Del Valle

Open Access Theses & Dissertations

In the finite dimensional ordered vector space Rn, we consider the standard positive cone to be the set Rn+ = {x : x ≥ 0} for an element x in Rn. Given a subspace V of Rn, we define the positive cone of V to be the intersection of V with Rn+. The cone V+ is said to be generating if V = V+V+, that is, if any vector v in V can be expressed as the difference of two vectors, v = …


The Reactivity Of Potassium Carbanions With Epoxides, Christina Dorado Jan 2011

The Reactivity Of Potassium Carbanions With Epoxides, Christina Dorado

Open Access Theses & Dissertations

The reaction of &alpha-cumylpotassium and cyclohexene oxide produces trans-cumylcyclohexanol in high yield in the presence of excess cumene. Reactions of 1.1 and 2.0 equivalents of cumene with one equivalent of n-butylpotassium to make &alpha-cumylpotassium were shown to take several days to reach a maximum yield in the subsequent reaction of &alpha-cumylpotassium and cyclohexene oxide. Although it was initially hypothesized that the high yield was attributed to the interaction of the potassium with the aromatic rings of the &alpha-cumyl anion and the excess cumene, which was confirmed by molecular modeling studies, these reactions demonstrated that no large excess of …


A Web Site-Level Implementation Of Owl Sameas Predicate In Drupal, Patricia Esparza Jan 2011

A Web Site-Level Implementation Of Owl Sameas Predicate In Drupal, Patricia Esparza

Open Access Theses & Dissertations

The Ontology Web Language (OWL) sameAs predicate states that if the predicate holds between two Uniform Resource Identifiers (URIs) A and B, then an object identified by A is the same object identified by B; its purpose is to enable machines to understand that both objects are the same although they may have distinct Web identifiers, i.e., URIs. The proliferation of the use of this predicate has brought several issues to the Web, e.g., high cost of manually creating sameAs statements, inconsistent use of the predicate leading to distinct objects to be identified as being a single object, and too …