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Articles 2131 - 2160 of 2636

Full-Text Articles in Physical Sciences and Mathematics

Extracting Fuzzy Measures From Sample Data: Optimization Algorithms And Applications, Xiaojing Wang Jan 2013

Extracting Fuzzy Measures From Sample Data: Optimization Algorithms And Applications, Xiaojing Wang

Open Access Theses & Dissertations

In Multi-Criteria Decision Making (MCDM), decisions are based on several criteria that are usually conflicting and non-homogenously satisfied. We use non-additive (fuzzy) measures combined with the Choquet integral to solve MCDM problems, for they allow to model and aggregate the levels of satisfaction of the several criteria of the problem at hand by considering the relationship between these criteria. In practice, it is difficult to identify such fuzzy measures. An automated process is then necessary and can be used when sample data is available. Several optimization approaches have been used to extract fuzzy measures from sample data, for example, genetic …


Recovering Magnesium Hydroxide And Sodium Chloride From Zero Discharge Desalination Concentrate Streams, Alemayehu Asfaw Yetayew Jan 2013

Recovering Magnesium Hydroxide And Sodium Chloride From Zero Discharge Desalination Concentrate Streams, Alemayehu Asfaw Yetayew

Open Access Theses & Dissertations

UTEP and Veolia Water Solutions & Technologies have been demonstrating and commercializing the Zero Discharge Desalination (ZDD) technology as part of a three year project sponsored by the U.S. Bureau of Reclamation. ZDD is able to achieve up to 98% recovery by desalinating brackish groundwater. ZDD is typically comprised of a reverse osmosis (RO) or nanofiltration (NF) system and a unique variation of electrodialysis called electrodialysis metathesis (EDM). The ZDD technology increases the yield of fresh water from water supplies that contain enough CaSO4 to cause precipitation problems when the water is treated with RO or NF alone. The EDM …


Determinants Of Neighborhood Exposure To Extreme Heat: A Spatial Examination Of El Paso And Juárez, 2010, Faraj Mohamad Aboargob Jan 2013

Determinants Of Neighborhood Exposure To Extreme Heat: A Spatial Examination Of El Paso And Juárez, 2010, Faraj Mohamad Aboargob

Open Access Theses & Dissertations

Numerous studies have been conducted on the modification of local weather by the urban environment. In studying urban environmental effects on the urban heat island (UHI), researchers have investigated influences such as land use, vegetation density, topography, population density, and neighborhood socioeconomic status. Many studies have used data collected from field observations, while other studies relied solely on computer modeling. This Dissertation research used a spatial analysis approach, which has been less widely employed, to investigate neighborhood level biophysical, built environmental and socio-demographic determinants of the El Paso and Juárez UHI. The research utilized inexpensive data obtained from US and …


Interaction Of Ceo2 And Zno Nanoparticles Towards The Symbiotic Association Of Alfalfa (Medicago Sativa) And Sinorhizobium Meliloti In Soil, Susmita Bandyopadhyay Jan 2013

Interaction Of Ceo2 And Zno Nanoparticles Towards The Symbiotic Association Of Alfalfa (Medicago Sativa) And Sinorhizobium Meliloti In Soil, Susmita Bandyopadhyay

Open Access Theses & Dissertations

The production of engineered nanoparticles (ENPs) has rapidly increased due to their wide range of applications in the field of electronics, medicine, chemistry and biology. Consequently, concerns have risen about the environmental release and potential negative impact of NPs. A few reports have described the effects of TiO2 NPs and quantum dots upon nitrogen fixing bacteria. However, the understanding of the interaction of NPs in plant-microbe interface (symbiotic association), like alfalfa (Medicago sativa L.)-Sinorhizobium meliloti, is still in its infancy. Alfalfa is the world's most important forage crop. It grows in association with S. meliloti, which is very important in …


Preparation Of Cobalt/Nickel Molybdenum Sulfide Catalysts Supported By Aqueous Media Soluble Multi-Wall Carbon Nanotubes., Hassan Ahmad Bleibel Jan 2013

Preparation Of Cobalt/Nickel Molybdenum Sulfide Catalysts Supported By Aqueous Media Soluble Multi-Wall Carbon Nanotubes., Hassan Ahmad Bleibel

Open Access Theses & Dissertations

Multi-walled carbon nanotubes (MWCNTs) have been subjected to chemical treatment in order to introduce hydrophilic functional groups on their surfaces. These covalently bonded groups did enhance the solubility of MWCNTs in aqueous media as expected. Functionalized MWCNTs were characterized using FTIR, Raman spectroscopy, TGA, X-ray diffraction, dispersion test and TEM. Then, functionalized MWCNTs were incorporated in the hydrothermal synthesis method of transition metal sulfide catalysts (CoMo, NiMo, and Ethylenediamine-CoMo Sulfides). Catalysts were characterized using X-ray diffraction, TEM, SEM, N2 Gas adsorption-desorption, elemental analysis, and Hydrodesulfurization (HDS) reaction of dibenzothiophene (DBT). The objective was to study the functionalized MWCNTs' effect; being …


Integrated Geological And Geophysical Studies Of The Indio Mountains And Hueco Bolson, West Texas, Pawan Budhathoki Jan 2013

Integrated Geological And Geophysical Studies Of The Indio Mountains And Hueco Bolson, West Texas, Pawan Budhathoki

Open Access Theses & Dissertations

This Dissertation consists of two different projects. The first project describes the results of an outcrop based sequence stratigraphic study of the Albian Cox Sandstone in the Indio Mountains of west Texas. The depositional environment of the Cox Sandstone ranges from shallow marine to the coastal plain deposited in four sequences where sequence 1 and sequence 2 consists of transgressive system tracts (TST) followed by highstand system tracts (HST). The highstand system tract (HST) is missing in sequence 3 and the transgressive systems tract is missing in sequence 4. The Cox changes in thickness from 320 m in the northern …


Lead And Associated Heavy Metal Distribution In El Paso, Texas, Ali Ragab Elkekli Jan 2013

Lead And Associated Heavy Metal Distribution In El Paso, Texas, Ali Ragab Elkekli

Open Access Theses & Dissertations

Contamination by lead and other heavy metals is one of the most important environmental concerns of today, locally and globally. This issue has led scientists and researchers to study the effect of heavy metals and their distribution in the environment. The aim of the present research is to document the concentration and geographic distribution of heavy metals in El Paso.

The selected heavy metals in the El Paso soil are lead, cadmium, chromium, zinc, antimony and copper. The soil sample for the study was collected during a previous community lead study (RO1 ESO11367; 2001-2006). 500 superficial soils samples were collected …


Seismic Reflection Exploration Of Geothermal Reservoir Atnaval Air Station (Nas) Fallon, Nevada, Alay Ghebremariam Gebregiorgis Jan 2013

Seismic Reflection Exploration Of Geothermal Reservoir Atnaval Air Station (Nas) Fallon, Nevada, Alay Ghebremariam Gebregiorgis

Open Access Theses & Dissertations

The Primary objective of this study is to increase geologic and tectonic understanding of the geothermal resources at the Naval Air Station (NAS) Fallon, Nevada. The seismic reflection method is employed to study faults, fractures and other tectonic structures in the subsurface in order to identify geothermal drill targets. The efficiency of geothermal systems is strongly dependent on water circulation. Discrete faults may be permeable and provide pathways for water flow depending on the fracture density. It is therefore desirable to detect and map faults and fracture zones and characterize their physical properties when evaluating a geothermal prospect.

The seismic …


Summer Land Surface Temperature: Small-Local Variation In Intro-Urban Environment In El Paso, Tx, Mactar Mohamed Jan 2013

Summer Land Surface Temperature: Small-Local Variation In Intro-Urban Environment In El Paso, Tx, Mactar Mohamed

Open Access Theses & Dissertations

ABSTRACT

It has been well documented that rapid urbanization and population growth have led to the transformation of the natural landscape into anthropogenic urban land and changed such surface physical properties as albedo, energy balance, and surface roughness. Cities, therefore, will be warmer at the urban areas than the rural lands; this situation creates a phenomenon called Urban Heat Island (UHI).

In the recent decades, numerous approaches to study the variation of land surface temperature during daytime have emerged; however, little is known about the variation during nighttime. This study addressed the spatial variation of Summer Nighttime Land Surface Temperature …


Rbd2po4: Room Temprature Synthesis, Chemical And Structural Stablity Upon Heating, Masoud Mollaee Jan 2013

Rbd2po4: Room Temprature Synthesis, Chemical And Structural Stablity Upon Heating, Masoud Mollaee

Open Access Theses & Dissertations

Monoclinic RbD2PO4 polycrystals were synthesized via the room temperature crystallization of RbH2PO4 dissolved in D2O. Powder x-ray diffraction (XRD) data collected at T=25 ºC indicate that this deuterated compound crystallizes in space group P21/m with unit cell parameters a=7.688í?, b=6.192í?, c=4.781í? and β=109.02°, and is isomorphic with the intermediate-temperature phase of its hydrogenated counterpart rubidium dihydrogen phosphate (RDP). We found no evidence of previously reported [Phase Transitions 80, 17 (2007)] polymorphic phase transition in rubidium dideuterium phosphate (DRDP) upon heating from room temperature to 210 ºC. All lattice parameters vary smoothly within this temperature range, demonstrating that the P21/m phase …


Automatic Memory Management Policies For Low Power, Memory Limited, And Delay Intolerant Devices, Md Abu Jahid Jan 2013

Automatic Memory Management Policies For Low Power, Memory Limited, And Delay Intolerant Devices, Md Abu Jahid

Open Access Theses & Dissertations

Mobile devices such as smartphones and tablets are energy and memory limited, and implement graphical user interfaces that are intolerant of computational delays. Mobile device platforms supporting apps implemented in languages that require automatic memory man- agement, such as the Dalvik (Java) virtual machine within Google's Android, have become dominant. It is essential that automatic memory management avoid causing unacceptable interface delays while responsibly managing energy and memory resource usage. Dalvik's automatic memory management policies for heap growth and garbage collection scheduling utilize heuristics tuned to minimize memory footprint. These policies result in only marginally acceptable response times and garbage …


Using Emotion As Inferred From Prosody In Language Modeling, Shreyas Ashok Karkhedkar Jan 2013

Using Emotion As Inferred From Prosody In Language Modeling, Shreyas Ashok Karkhedkar

Open Access Theses & Dissertations

Research has focused on using prosody as an alternative source of information for language modeling. However, prosody is a surface phenomenon and to develop deeper models of language production, the underlying mental processes need to be considered. There are several cognitive factors, such as dialog-states and formulation, that have been given attention. However, emotion { as a cognitive factor, has been neglected so far. Speakers' emotional state plays an important role in spoken dialog. Participants seem to infer each others emotional state from multiple cues and react accordingly. In particular, these states manifest themselves moment-by-moment in the speakers voice. This …


Geology And Geochemistry Of The Sierra Blanca Rare Earth Complex, Sierra Blanca, Texas, Nicole Kyger Jan 2013

Geology And Geochemistry Of The Sierra Blanca Rare Earth Complex, Sierra Blanca, Texas, Nicole Kyger

Open Access Theses & Dissertations

With an increasing standard of living comes an increase in demand for high tech goods, environmentally friendly (green) and military technologies, and the inherent need to procure the necessary raw materials. Demand for the rare earth elements (REE) is on the rise, and there is no foreseeable decline in the need for accessible deposits. Between 2010 and present, the United States Congress has heard numerous reports on the importance of REE, and in 2012 the Department of Defense(DoD)declared REE a critical resource, with implications for national security. The Sierra Blanca laccoliths, 150 kilometers southeast of El Paso, TX represent a …


Modeling Visibility In The El Paso Del Norte (Pdn) Region, Richard Medina Calderon Jan 2013

Modeling Visibility In The El Paso Del Norte (Pdn) Region, Richard Medina Calderon

Open Access Theses & Dissertations

Poor visibility is a subject of growing public concern throughout the U.S, and an active area of research. Its societal impacts on air quality, aviation transport and traffic are significant. Aerosols play a fundamental role in the attenuation of solar radiation, and also affect visibility. The scattering and extinction coefficients of aerosol particles in the Paso del Norte Region have been calculated using the T- matrix model in conjunction with a laser particle counter. Inter-comparison of the model's results of the scattering and absorption coefficients against the corresponding data from a Photoacustic extinctiometer instrument (which measures in-situ absorption and scattering …


Cjc: An Extensible Checker For The Cleanjava Annotation Language, Cesar Eduardo Yeep Jan 2013

Cjc: An Extensible Checker For The Cleanjava Annotation Language, Cesar Eduardo Yeep

Open Access Theses & Dissertations

Formal program verification can be used as a complementary technique to software testing. It allows checking the correctness of all the states of a program which may be impossible using only software testing as a verification technique. One software development process that relies on formal verification is Cleanroom Software Engineering. Cleanroom's main principles are to certify the software with respect to its specification and to produce zero-fault or near-zero-fault software. Cleanroom has being tested primarily in safety-critical systems that require a high level of correctness by development teams in places such as NASA and IBM, demonstrating lower fault rates and …


Modeling The Human Gait Phases Using Granular Computing, Melaku Ayenew Bogale Jan 2013

Modeling The Human Gait Phases Using Granular Computing, Melaku Ayenew Bogale

Open Access Theses & Dissertations

Gait analysis is applied for the provision of diagnosis, evaluation, and for the design of therapeutic intervention for subjects suffering from neurological disorders. The benefits accruing from gait analysis are well established. People with neurological disorders like mild traumatic brain injury, Cerebral Palsy and Multiple Sclerosis, suffer associated functional gait problems. The symptoms and sign of these gait deficits are different from subject to subject and even for the same subject at different stage of the disease. Identifying these gait related abnormalities helps in the treatment planning and rehabilitation process.

The dynamic behavior of gait parameters is cyclic and the …


Size-Dependent Transitions In Grafted Polymer Brushes, Courtney Bosse Jan 2013

Size-Dependent Transitions In Grafted Polymer Brushes, Courtney Bosse

Open Access Theses & Dissertations

ABSTRACT

Finding probabilities in order to solve for the most likely configuration of a grafted polymer chain is easily calculated by solving a random walk problem, starting form a given point (the surface). A property of the random walk is used to describe the partition function of a polymer in terms of a sum over possible loops configurations, which simplifies tremendously the problem of calculating the partition function of the grafted polymer. Instead of solving the non-interacting random walk that has been well studied in the theory of the probability, the focus is on the problem of self-interacting random walks, …


Thermal Barrier Coatings (Tbc's) For High Heat Flux Thrust Chambers, Christopher Michael Bradley Jan 2013

Thermal Barrier Coatings (Tbc's) For High Heat Flux Thrust Chambers, Christopher Michael Bradley

Open Access Theses & Dissertations

The last 30 years materials engineers have been under continual pressure to develop materials with a greater temperature potential or to produce configurations that can be effectively cooled or otherwise protected at elevated temperature conditions. Turbines and thrust chambers produce some of the harshest service conditions for materials which lead to the challenges engineers face in order to increase the efficiencies of current technologies due to the energy crisis that the world is facing. The key tasks for the future of gas turbines are to increase overall efficiencies to meet energy demands of a growing world population and reduce the …


Quark Fluctuations In A Chiral Model In The Presence Of A Magnetic Field, Lidens Cheng Jan 2013

Quark Fluctuations In A Chiral Model In The Presence Of A Magnetic Field, Lidens Cheng

Open Access Theses & Dissertations

Understanding the nature of the chiral and deconfinement phase transitions, the location of the critical point, and the properties in its vicinity are among the most important problems in the field of QCD. The purpose of this thesis is to use the two-flavor Nambu-Jona-Lasinio model in the presence of a magnetic field at the chiral limit to study the phase boundary where the spontaneously broken chiral symmetry is restored. At small chemical potential, the phase boundary exhibits a second-order phase transition. On the other hand, at large chemical potential and appropriate coupling constant, the phase boundary exhibits a first-order phase …


A Block Operator Splitting Method For Heterogeneous Multiscale Poroelasticity, Paul M. Delgado Jan 2013

A Block Operator Splitting Method For Heterogeneous Multiscale Poroelasticity, Paul M. Delgado

Open Access Theses & Dissertations

Traditional models of poroelastic deformation in porous media assume relatively homogeneous material properties such that macroscopic constitutive relations lead to accurate results. Many realistic applications involve heterogeneous material properties whose oscillatory nature require multiscale methods to balance accuracy and efficiency in computation.

The current study develops a multiscale method for poroelastic deformation based on a fixed point iteration based operator splitting method and a heterogeneous multiscale method using finite volume and direct stiffness methods. To characterize the convergence

of the operator splitting method, we use a numerical root finding algorithm to determine a threshold surface in a non-dimensional parameter space …


Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez Jan 2013

Rare Earth Element Geochemistry Of The Sierra Blanca Laccoliths, Texas, Amed Gomez

Open Access Theses & Dissertations

No abstract provided.


Reduced-Order Modeling Using Orthogonal And Bi-Orthogonal Wavelet Transforms, Miguel Hernandez Iv Jan 2013

Reduced-Order Modeling Using Orthogonal And Bi-Orthogonal Wavelet Transforms, Miguel Hernandez Iv

Open Access Theses & Dissertations

It is well known that model reduction methods borrow techniques typically found in data compression, and current state-of-the-art techniques for data compression are based on the wavelet transform. Given these facts, it is surprising that model reduction using wavelets has not received much attention and has not been adequately addressed in the literature. This research seeks to determine if wavelets can be used for model reduction and if wavelet model reduction is a viable alternative to existing model reduction methods.

In this work we propose a novel method for model reduction using wavelets. Specifically, we introduce techniques for deriving wavelet …


Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano Jan 2013

Method Development For A Chemical And Biological Analysis Of Glucocorticoids In Wastewater, Maria Carmen Lozano

Open Access Theses & Dissertations

Glucocorticoids are a class of steroid hormones that can either be produced synthetically or naturally by the adrenal glands. The synthetic glucocorticoids are highly prescribed in the United States for their anti-inflammatory and immunosuppressive properties to treat a variety of ailments and diseases; however, these have been implicated in a number of adverse human conditions such as obesity, metabolic syndrome, immune-suppression, delayed puberty, adrenal insufficiency and Cushing Syndrome, among others. Ongoing research has shown that synthetic and natural hormones are transported to aquatic environments via mammalian excretion or wastewater effluent, and as a result, the release of glucocorticoids into the …


In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar Jan 2013

In-Situ, Integrated U-Pb, Hf And O Isotopic Study Of Igneous, Metamorphic And Detrital Zircons. Implications To Crustal Evolution And Geodynamics, Munazzam Ali Mahar

Open Access Theses & Dissertations

Zircon data from South Karakoram gneiss dome provide evidence for Proterozoic inherited cores (1.8-1.9 Ga and 2.3-.2.5 Ga) surrounded by migmatitic overgrowth with ages ranging from ~6 to ~20Ma. Oxygen isotopic data of Neogene migmatite and inherited core is similar and indistinguishable ranging from 7.5 to 9.5 /. However, Neogene overgrowth is significantly less evolved than the inherited core in terms of Hf composition. This implies that the Hf composition of the migmatitic zircons is not controlled exclusively by the dissolution of the inherited cores and that contamination by external melts is likely. Isotopic data from the Baltoro plutonic unit …


Endocrine Disrupting Compound 4-Nonylphenol And Neurodegeneration, Jessica Martinez Jurado Jan 2013

Endocrine Disrupting Compound 4-Nonylphenol And Neurodegeneration, Jessica Martinez Jurado

Open Access Theses & Dissertations

Neurodegeneration, a progressive loss of nerve cells (neurons), occurs in many neurological disorders including Alzheimer's disease, Parkinson's disease, Schizophrenia, and drug addiction. Cytoskeletal disruption in neurons and aggregation of proteins associated with these disorders is the hallmark of neurodegeneration. However, the cause of neurodegenerative disorders is unknown and currently there are no effective drug treatments. Aging is the most consistent risk factor for developing a neurodegenerative disorder, and recent evidence suggests that environmental factors, which act as endocrine disruptors, pose a risk in the disease process. 4- nonylphenol (4-NP), an endocrine-disrupting compound (EDC), has been shown to affect brain development …


The Eolian-Sabkha Transition In The Permian Cedar Mesa Sandstone, Se Utah, Alexandra Massad Jan 2013

The Eolian-Sabkha Transition In The Permian Cedar Mesa Sandstone, Se Utah, Alexandra Massad

Open Access Theses & Dissertations

This study focuses on the depositional transition between the Permian Cedar Mesa sand dune sea and the adjoining fluvial, lacustrine, playa and a sabkha facies. This transition provides insights into how climate and environment interacted in this unique setting where up to 300 m of eolian sands transition into evaporites. The evaporites are less common as tongues within the eolianites than previously thought and there were several environments that were observed that haven't been previously described or observed in the Cedar Mesa. The arrangement of the various units within the study area support the climate control on stratigraphy.

The intertonguing …


Investigating The Validity Of A Survey Intended To Gauge Mathematics Problem-Solving Disposition Along The Impulsive-Analytic Dimension, Miguel Mendoza Jan 2013

Investigating The Validity Of A Survey Intended To Gauge Mathematics Problem-Solving Disposition Along The Impulsive-Analytic Dimension, Miguel Mendoza

Open Access Theses & Dissertations

This study investigates the validity of the Likelihood-to-Act (LtA) survey developed to assess respondents' problem-solving disposition along the impulsive-analytic dimension. Sixteen pre-service teachers were strategically selected from a pool of 495 LtA survey respondents to participate in a semi-structured task-based interview approximately one hour in length. The interview consisted of three main parts: a problem solving section, a consistency section, and a classification section.

* Part 1 of the interview was developed to get interviewees to solve five open-response problems meant to elicit an impulsive response. Interviewees were also asked to verbalize their thought process in order for the researchers …


Two-Photon Microscopy Of Nanoparticles And Biotissues, Judith Noemi Rivera Jan 2013

Two-Photon Microscopy Of Nanoparticles And Biotissues, Judith Noemi Rivera

Open Access Theses & Dissertations

Biomedical Imaging is an important tool in medical research and clinical practice. From understanding the fundamental processes involved in our biological makeup to its use in diagnostics in helping determine what ails us, the advancements in imaging and microscopy have helped shape our view of the world and nature. Microscopy in particular is often used to study the smallest of cells and their dynamical properties while attempting to minimally change the sample being studied. My research objective is largely divided into two parts. The first part consists of designing a video-rate raster scanning two-photon microscope that is faster than current …


Environmental Education Through The Lens Of Diverse Elementary School Students In The United States: A Phenomenographic Study, Brissa Yazmin Quiroz Jan 2013

Environmental Education Through The Lens Of Diverse Elementary School Students In The United States: A Phenomenographic Study, Brissa Yazmin Quiroz

Open Access Theses & Dissertations

Global environmental change is occurring, putting our planet under pressure. Children need to understand not only why the environment is important, but also their role as citizens of a globalized society and their necessary contribution to solving global problems. Students carry their own perspectives about the environment and education, and these differing perspectives should be a significant topic for environmental education research. Recent research studies have included the conceptualization of nature and the environment through children's eyes; yet, no studies have examined the concept of environmental education through the eyes of diverse children. Minority voices and experiences are not frequently …


Heavy Metal Pollution In The Paso Del Norte Region:Historical Reconstruction And Source Interpretation, Eugenia G. Shekhter Jan 2013

Heavy Metal Pollution In The Paso Del Norte Region:Historical Reconstruction And Source Interpretation, Eugenia G. Shekhter

Open Access Theses & Dissertations

A unique and complex situation of heavy metal pollution arose in the El Paso del Norte region, one of the largest and oldest metropolitan areas on the US-Mexican border. This region with its complex topography is home to more than 2.2 million people sharing the same environment. Although many studies have been conducted in the region to identify the sources of environmental contamination, the cumulative history of heavy metal pollution is still incomplete. In order to identify the patterns of heavy metal dispersion and to test the hypothesis that the American Smelting and Refining Company (ASARCO) was a considerable contributor …