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Articles 721 - 750 of 1380
Full-Text Articles in Physical Sciences and Mathematics
Bragg Gratings In Polarization Maintaining Optical Fiber As Three Dimensional Strain Sensor, Joel Quintana
Bragg Gratings In Polarization Maintaining Optical Fiber As Three Dimensional Strain Sensor, Joel Quintana
Open Access Theses & Dissertations
Fiber-Bragg Gratings (FBG) for Structural Health Monitoring (SHM) have been studied extensively as they offer electrically passive operation, electromagnetic interference (EMI) immunity, high sensitivity and multiplexing as compared to conventional electric strain sensors. FBG sensors written within polarization maintaining (PM) optical fiber offer ad- ditional dimensions of strain measurement, greatly reducing the number of sensors needed to properly monitor a structure. This reduction however, adds complexity to the dis- crimination of the sensorâ??s optical response to its corresponding applied strains. This Dissertation defines the set of algorithms needed to measure planar strain using PM-FBGs exclusively. It defines the minimum number …
Developing A System Dynamics Model Of The El Paso Water Resources System, Majid Alahmoradi
Developing A System Dynamics Model Of The El Paso Water Resources System, Majid Alahmoradi
Open Access Theses & Dissertations
The city of El Paso is growing rapidly, increasing water demand in a water-scarce region. In this research system dynamics modeling is applied to simulate dynamic behavior of the El Paso water resources system in order to investigate the city's portfolio based upon a supply-demand side and demand side management approach. System Dynamic simulation involves several steps, including system conceptualization, data collection, simulation model development, and model verification and sensitivity analysis. A high-level conceptualization of the El Paso water resources system is presented, including withdrawal sources, water and wastewater treatment facilities, water demands, and flow linkages are will be presented. …
Studies Of Direct Solar Irradiance And Aerosol Optical Depth Using An Mfrsr And A Microtop Sunphotometer In The El Paso-Juarez Airshed, Arjun Aryal
Open Access Theses & Dissertations
The study of Solar Irradiance and Aerosol Optical Depth (AOD) plays an important role in understanding the regional and global climate distribution, and is also important in air pollution studies. In this work an MFRSR (Multi-Filter Rotating Shadowband Radiometer) and a Portable Microtop Sunphotometer were used to measure irradiances and to obtain optical depth values for the El Paso-Juarez Airshed. The Langley method applied on the MFRSR irradiance data was used to calculate the AOD values. The spatial distribution of AOD for this region was obtained using a Microtop Sunphotometer. The graphs were generated using GIS Shapefiles. In addition, the …
Studies Of Air Pollutants And Their Impact On Respiratory And Cardiovascular Diseases In The El Paso Del Norte Region With Emphasis On Mobile Emissions, Juan Gustavo Arias Ugarte
Studies Of Air Pollutants And Their Impact On Respiratory And Cardiovascular Diseases In The El Paso Del Norte Region With Emphasis On Mobile Emissions, Juan Gustavo Arias Ugarte
Open Access Theses & Dissertations
Air pollution may cause different diseases, such as cardiovascular and lung diseases. Traffic is a major source of mobile emissions causing air pollution. Exhaust emissions from mobile sources (Emissions of Carbon Monoxide, Nitrogen Oxides and Hydrocarbons) and Non-exhaust (Brake and Tire) are complex mixtures of gases and dust, including a large number of ultrafine particles, especially in areas with high traffic density. Recent studies have shown high rates of morbidity and mortality in people exposed to these types of emissions because the fine and ultrafine particles can be transported from the respiratory airways to the organs, thus contributing to increase …
Computational Methods For Prediction And Classification Of G Protein-Coupled Receptors, Khodeza Begum
Computational Methods For Prediction And Classification Of G Protein-Coupled Receptors, Khodeza Begum
Open Access Theses & Dissertations
G protein-coupled receptors (GPCRs) constitute the largest group of membrane receptor proteins in eukaryotes. Due to their significant roles in many physiological processes such as vision, smell, and inflammation, GPCRs are the targets of many prescribed drugs. However, the functional and structural diversity of GPCRs has kept their prediction and classification based on amino acid sequence data as a challenging bioinformatics problem. As existing computational methods to predict and classify GPCRs are focused on mammalian (mostly human) data, the ultimate goal of our project is to establish an ensemble approach and implement a web-based software that can be used reliably …
Utilizing Historical Mosquito Surveillance Data To Investigate The Efficacy Of Municipal Fogging In Controlling Mosquito Population Density, Andrea Betina Carzoli
Utilizing Historical Mosquito Surveillance Data To Investigate The Efficacy Of Municipal Fogging In Controlling Mosquito Population Density, Andrea Betina Carzoli
Open Access Theses & Dissertations
Background: Mosquito borne diseases are the cause of many different disease syndromes and deaths in animals, both wild and domesticated, and humans of all ages and ethnicities. Though El Paso, TX is located in an arid region, mosquito populations are still rapidly growing in urban and agricultural communities and so are the mosquito borne illnesses. The most common vectors associated with mosquito borne illnesses in El Paso County are Culex quinquefasciatus, Culex tarsalis, and Aedes aegypti. Vector management is often the primary option to prevent and control outbreaks of mosquito borne illnesses and very often utilize fogging as the primary …
Methods For Producing Graphene From Petroleum By-Products, Eva M. Deemer
Methods For Producing Graphene From Petroleum By-Products, Eva M. Deemer
Open Access Theses & Dissertations
N/A
Predicting Individualized Treatment Effects Via Random Forests Of Interaction Trees, Annette Pena Franco
Predicting Individualized Treatment Effects Via Random Forests Of Interaction Trees, Annette Pena Franco
Open Access Theses & Dissertations
Abstract Not Available
Analysis Of Bias-Corrected And Exact Estimators For Binomial Generalized Linear Model Parameters, Hamna Hannan
Analysis Of Bias-Corrected And Exact Estimators For Binomial Generalized Linear Model Parameters, Hamna Hannan
Open Access Theses & Dissertations
Typically, small samples have always been a problem for binomial generalized linear models. Though generalized linear models are widely popular in public health, social sciences etc. In small sample scenarios the non-existence of the maximum likelihood (ML) estimators is very common as well as separation occurs in the data. In logistic regression the maximum likelihood estimates are found to have biased away from origin. My work examines the bias-reduced and exact estimators that have been used to estimate the slope parameters and standard errors of the estimated slope parameters as compared to the traditional ML method.
The present work is …
Quantifying The Characteristic Length Of A Combustor For An Ionic Liquid Monopropellant Thruster, Kimberly Marie Hogge
Quantifying The Characteristic Length Of A Combustor For An Ionic Liquid Monopropellant Thruster, Kimberly Marie Hogge
Open Access Theses & Dissertations
Ionic liquid monopropellants are currently being researched as a promising alternative to hydrazine in propulsion systems. This report presents a flame study that delineates the flame length of the expected decomposition products from an ionic liquid monopropellant. Through these studies, the characteristic length of a combustion chamber will be defined through calculations and empirical correlations. There is limited information on designing a propulsion system for an ionic liquid monopropellant. Therefore, defining the magnitude for an effective characteristic length serves as beneficial in designing a propulsion system for an ionic liquid monopropellant thruster.
Ac Susceptibility And Epr Investigations Of Superspin Dynamics In Manganese Oxide Nanoparticles, Mahesh Koirala
Ac Susceptibility And Epr Investigations Of Superspin Dynamics In Manganese Oxide Nanoparticles, Mahesh Koirala
Open Access Theses & Dissertations
We have investigated the superspin dynamics of 5 nm and 10 nm mixed state Mn3O4 nanoparticles utilizing ac-susceptibility and electron paramagnetic resonance measurements. The out of phase component of the ac-susceptibility measurements show a magnetic anomaly below (T
Cost-Effective Recovery Of Concentrated Cooling Tower Blowdown Using The Cerro Process, Lindsey Nicole Larson
Cost-Effective Recovery Of Concentrated Cooling Tower Blowdown Using The Cerro Process, Lindsey Nicole Larson
Open Access Theses & Dissertations
The Concentrate Enhanced Recovery Reverse Osmosis (CERRO) process is a seawater-RO unit that can cost-effectively achieve extremely high recoveries from water high in silica, carbonate and sulfate concentrations. This relatively new technology takes advantage of the induction time of potential foulants to recover more water than what is normally achievable with a conventional desalination system. The scope of the project was to evaluate the efficiency of the CERRO process as a pilot study using cooling tower blowdown which varied in water quality parameters daily. It was found that the CERRO pilot could successfully achieve 85% recovery, and the main limitation …
Gypsum, Calcite, And Dolomite Caprock Fabrics And Geochemistry From The Gypsum Valley Salt Diapir, Paradox Basin, Southwestern Colorado, Kevin Lerer
Open Access Theses & Dissertations
Caprocks are found on top of or in a lateral position relative to salt diapirs. The caprocks predominantly comprise sulfate minerals such as anhydrite or gypsum, which presumably accreted during the dissolution of salt from evaporite sediments. In some cases, the sulfate minerals are replaced by carbonate minerals, referred to as "carbonate caprock". Carbonate caprocks associated with salt diapirs are important because they can act as reservoirs or conduits for hydrocarbons, and because they can be easily misidentified as carbonate lithologies belonging to the stratigraphy of the sedimentary sequences adjacent to the diapir, which can jeopardize the accurate interpretation of …
A Comparison Of Uvr-Induced Mortality In Bdelloid Rotifers, Maite Martin
A Comparison Of Uvr-Induced Mortality In Bdelloid Rotifers, Maite Martin
Open Access Theses & Dissertations
Increases in UV radiation (UVR) reaching Earth's surface as a result of anthropogenic activities and changing climate patterns are having a variety of effects on ecosystems. Such effects have been observed in aquatic environments, although certain parameters such as dissolved organic carbon (DOC) concentrations can modulate the level of exposure. Bdelloid rotifers are aquatic micro-invertebrates that pose a remarkable variety of special abilities to survive adverse conditions, including a resistance to UVR. Previous studies have suggested this resistance may have evolved in response to episodes of desiccation that they experience in their natural habitats. This characteristic may be especially important …
Evaluation Of Cryptic Sulfur Cycling In Marine Sediments, Michael Ngari Mathuri
Evaluation Of Cryptic Sulfur Cycling In Marine Sediments, Michael Ngari Mathuri
Open Access Theses & Dissertations
Despite the importance of marine sediments as a carbon sink and many efforts to integrate microbiological with geochemical and geological data, the understanding of microbial organic carbon mineralization processes in marine sediments remains incomplete. There is growing evidence for the existence of an unrecognized oxidative sulfur cycling (cryptic sulfur cycling) above, within and below of the main sulfate reduction zone. For example, sulfate exists in supposedly sulfate-free methanogenic marine sediments from the Aarhus Bay and Black Sea. This implies that sulfur cycling is an ongoing process in the deep biosphere. Quantification of cryptic sulfur cycling is a major challenge because …
Airborne Lead In El Paso, Texas, Usa, Lisa Marie Paz
Airborne Lead In El Paso, Texas, Usa, Lisa Marie Paz
Open Access Theses & Dissertations
Despite significant strides to minimize lead in our air, water, soil, food, homes, workplaces, and consumer products, sporadic and systemic lead poisoning persists in industrial societies, e.g., the contemporary Flint (Michigan, USA) municipal water tragedy. Because lead exposure is cumulative, the sum of exposure from all sources, it is important to document and update potential community or neighborhood exposure levels from such environmental compartments as air, water, and housing. Here we present ambient airborne lead levels in El Paso, Texas, USA, parsed by particulate matter (PM) size fraction, geography, and season. Dichotomous samplers at 8 stations collected particulate matter continuously …
Combining Interval, Probabilistic, And Other Types Of Uncertainty In Engineering Applications, Andrew Martin Pownuk
Combining Interval, Probabilistic, And Other Types Of Uncertainty In Engineering Applications, Andrew Martin Pownuk
Open Access Theses & Dissertations
In many practical application, we process measurement results and expert estimates. Measurements and expert estimates are never absolutely accurate, their result are slightly different from the actual (unknown) values of the corresponding quantities. It is therefore desirable to analyze how this measurement and estimation inaccuracy affects the results of data processing.
There exist numerous methods for estimating the accuracy of the results of data processing under different models of measurement and estimation inaccuracies: probabilistic, interval, and fuzzy. To be useful in engineering applications, these methods should provide accurate estimate for the resulting uncertainty, should not take too much computation time, …
Analysing The Effects Of Data Augmentation And Free Parameters For Text Classification With Recurrent Convolutional Neural Networks, Jonathan Quijas
Analysing The Effects Of Data Augmentation And Free Parameters For Text Classification With Recurrent Convolutional Neural Networks, Jonathan Quijas
Open Access Theses & Dissertations
Convolutional neural networks have seen much success in computer vision and natural language processing tasks. When training convolutional neural networks for text classification tasks, a common technique is to transform an input sequence of words into a dense matrix of word embeddings, or words represented as dense vectors, using table lookup operations. This enables the inputs to be represented in a way that the well-known convolution/pooling operations can be applied to them in a manner similar to images. These word embeddings may be further incorporated into the neural network itself as a trainable layer to allow fine-tuning, usually leading to …
Describing Data And Workflow Provenance Using Design Patterns And Controlled Vocabularies, Smriti Rajkarnikar Tamrakar
Describing Data And Workflow Provenance Using Design Patterns And Controlled Vocabularies, Smriti Rajkarnikar Tamrakar
Open Access Theses & Dissertations
In any scientific experiment, researchers are required to access, compute, and analyze data to produce useful information to the scientific community. In order to instill trust on such scientific research products, the product users need to understand the procedure applied and the assumptions incorporated. The reuse and replication of reliable scientific data need methods that help the users to understand data origin and the derivation process, i.e. provenance. Although several standards for representing provenance such as PROV model (a W3C recommendation) have been recommended, they have not been widely utilized by scientific communities due to difficulty in aligning such recommended …
Innovations In Thermoelectric Materials Research: Compound Agglomeration, Testing And Preselection, Hugo Lopez
Innovations In Thermoelectric Materials Research: Compound Agglomeration, Testing And Preselection, Hugo Lopez
Open Access Theses & Dissertations
Thermoelectric materials have the capacity to convert a temperature differential into electrical power and vice versa. They will represent the next revolution in alternative energies once their efficiencies are enhanced so they can complement other forms of green energies that depend on sources other than a temperature differential.
Progress in materials science depends on the ability to discover new materials to eventually understand them and to finally improve their properties. The work presented here is aimed at dynamizing the screening of materials of thermoelectric interest. The results of this project will enable: theoretical preselection of thermoelectric compounds based on their …
Paper/Polymer Hybrid Microfluidic Biochips For Infectious Disease Diagnosis, Maowei Dou
Paper/Polymer Hybrid Microfluidic Biochips For Infectious Disease Diagnosis, Maowei Dou
Open Access Theses & Dissertations
Infectious diseases frequently cause public health concerns and they often occur in high-poverty regions. Hence, a simple and low-cost method is in great need for immediate and early diagnosis of infectious diseases. Recently, microfluidic lab-on-a-chip offers a unique opportunity for various biomedical applications. Since different chip substrates have different advantages and limitations, hybrid devices can draw more benefits from different substrates. Therefore, we have developed three paper/polymer hybrid microfluidic biochips integrated with loop-mediated isothermal amplification (LAMP) for high-sensitivity infectious disease diagnosis.
We for the first time developed a low-cost paper/polydimethylsiloxane (PDMS) hybrid microfluidic biochip for rapid, sensitive and instrument-free detection …
Touch And Step Potential Analysis At 23.9kv To 4.16kv & 13.8kv To 4.16kv Distribution Substations With Pad-Mounted Transformers, Floating Grounds, And Other Exposed Ungrounded Metal Bodies Using Winigs, David Guillermo Guzman
Touch And Step Potential Analysis At 23.9kv To 4.16kv & 13.8kv To 4.16kv Distribution Substations With Pad-Mounted Transformers, Floating Grounds, And Other Exposed Ungrounded Metal Bodies Using Winigs, David Guillermo Guzman
Open Access Theses & Dissertations
An electrical substation is composed of various subsystems that allow for the effective and safe operation of the power grid. One of the subsystems integrating a conventional substation is defined as the ground grid system. This system allows for the effective operation of the power grid and all the electrical equipment connected to it by providing a ground potential reference, commonly known as the system ground. In addition, the ground grid system provides safety to the workers and the public transiting inside or living nearby a substation by reducing the step and touch potential (or voltage) levels present during a …
The New Issues In Classification Problems, Md Mahmudul Hasan
The New Issues In Classification Problems, Md Mahmudul Hasan
Open Access Theses & Dissertations
The data involved with science and engineering getting bigger everyday. To study and organize a big amount of data is difficult without classification. In machine learning, classification is the problem of identifying a given data from a set of categories. There are several classification technique people using to classify a given data. In our work we present a sparse representation technique to perform classification. The popularity of this technique motivates us to use on our collected samples. To find a sparse representation, we used an $l_1$-minimization algorithm which is a convex relaxation algorithm proven very efficient by researchers. The purpose …
Controls On Carbonate Sedimentation And Sequence Stratigraphic Framework Of The Lower Permian (Wolfcampian) Hueco Formation (Upper-Middle And Gastropod Intervals), Robledo Shelf, Western Orogrande Basin, New Mexico, Matthew S. Harder
Open Access Theses & Dissertations
On the western margin of the Pennsylvanian/Permian Orogrande Basin, two composite measured sections in the Lower Permian upper interval of the Middle Member of the Hueco Limestone were analyzed in regards to depositional environment, facies and sequence stratigraphy. This can elucidate where potential unconventional reservoirs can be found in the Wolfcamp Shale of the Permian Basin. Based on these analyses, 12 lithofacies were identified, including 9 carbonate lithofacies: 1) fenestral dolomudstone, 2) peloidal dolomudstone, 3) ostracode foraminifera packstone, 4) foraminifera peloidal grainstone, 5) skeletal intraclast grainstone, 6) phylloid algal peloidal grainstone, 7) echinoderm phylloid algal packstone, 8) echinoderm bivalve brachiopod …
The Use Of Remote Sensing Technologies And Models To Study Pollutants In Pdn Region, Suhail Mahmud
The Use Of Remote Sensing Technologies And Models To Study Pollutants In Pdn Region, Suhail Mahmud
Open Access Theses & Dissertations
Using a suite of modeling techniques and instrumentation we study the atmospheric pollutants in the PdN Region. The first objective of this work was to measure hemi-spherically integrated, spectrally resolved solar photon flux (actinic flux) between the wavelengths 300 and 700 nm, and use the measured actinic flux to improve air quality simulations. Actinic flux was measured in the PdN region in order to calculate photolysis rate coefficients for different pollutants. The improved photolysis rate coefficients were then integrated into a photochemical air quality model (CAMx) in order to improve air quality forecasting. We present the simulations performed for a …
Evaluating The Effects Of The Phytohormone Indole-3-Acetic Acid In The Response Of Green Pea (Pisum Sativum L.) To Nanoscale Cuo Exposure In Soil, Loren Ochoa
Open Access Theses & Dissertations
The response of plants to copper oxide nanoparticles (nCuO) in presence of the phytohormones such as IAA, is unknown. In this study, green pea (Pisum sativum) plants were cultivated to full maturity in soil amended with nCuO, CuO bulk (bCuO), and CuCl2 at 50 and 100 mg/kg and indole-3-acetic acid (IAA) at 10 and 100 µM. Several analytical techniques were used to evaluate the effects of treatments in the agronomical, physiological, and biochemical effects of treatments. Results showed that only CuCl2 reduced root length and number of leaves. Root copper (Cu) increased in plants exposed to nCuO without IAA; however, …
Synthesis, Characterization, And Functional Evaluation Of Nanocomposites For Water Purification, Julio Eduardo Padilla
Synthesis, Characterization, And Functional Evaluation Of Nanocomposites For Water Purification, Julio Eduardo Padilla
Open Access Theses & Dissertations
The United Nations estimate that around 780 million people do not have access to clean and safe water and around 2.5 billion people do not have proper water sanitation. As a result, around 6-8 million people die each year due to water related diseases, such as cholera and dysentery, and disasters. As population increases the water problem will become more difficult to solve. Furthermore, climate change threatens to intensify water scarcity. The design of functional materials at the nanoscale offer unique solutions in molecular sorbents and catalytic systems that can develop into cost-effective solutions in water treatment by reducing the …
An Effective And Optimal Quality Control Approach For Green Energy Manufacturing Using Design Of Experiments Framework And Evolutionary Algorithm, Juan Alejandro Saavedra
An Effective And Optimal Quality Control Approach For Green Energy Manufacturing Using Design Of Experiments Framework And Evolutionary Algorithm, Juan Alejandro Saavedra
Open Access Theses & Dissertations
Quality Control (QC) and Quality Assurance (QA) strategies vary significantly across industries in the manufacturing sector depending on the product being built. Such strategies range from simple statistical analysis and process controls, decision-making process of reworking, repairing, or scraping defective product. This study proposes an optimal QC methodology in order to include rework stations during the manufacturing process by identifying the amount and location of these workstations. The factors that are considered to optimize these stations are cost, cycle time, reworkability and rework benefit. The goal is to minimize the cost and cycle time of the process, but increase the …
Forecasting Customer Electricity Load Demand In The Power Trading Agent Competition Using Machine Learning, Saiful Abu
Forecasting Customer Electricity Load Demand In The Power Trading Agent Competition Using Machine Learning, Saiful Abu
Open Access Theses & Dissertations
Accurate electricity load demand forecasting is an important problem in managing the power grid for both economic and environmental reasons. The Power TAC simulation provides a platform to do research on smart grid energy generation and distribution systems. Brokers are the focus of the design task posed to developers by the system. The brokers work as self-interested entities that try to maximize profits by trading electricity across multiple markets. To be successful, a broker has to forecast the electricity demand for customers as accurately as possible so it can use this information to operate efficiently. My proposed forecasting method uses …
Assessing Accuracies And Improving Efficiency For Segmentation-Based Rna Secondary Structure Prediction Methods, Gerardo A. Cardenas
Assessing Accuracies And Improving Efficiency For Segmentation-Based Rna Secondary Structure Prediction Methods, Gerardo A. Cardenas
Open Access Theses & Dissertations
RNA secondary structure prediction has become an important area of interest in biology and medicine because it helps in understanding the mechanisms of many biological processes such as gene regulation and viral replication, and in designing RNA-based therapies to treat various diseases such as cancers and AIDS. Different thermodynamics-based computational algorithms for RNA structure prediction exist, and have been used to help understand the disease mechanisms and design treatments. However, most of these computational tools that can predict complex pseudoknot structures have a sequence length limitation of few hundred nucleotide bases due to their high demands of computer resources. Yet, …