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Articles 138391 - 138420 of 303849

Full-Text Articles in Physical Sciences and Mathematics

Probabilistic Graphical Modeling On Big Data, Ming-Hua Chung Dec 2015

Probabilistic Graphical Modeling On Big Data, Ming-Hua Chung

Graduate Theses and Dissertations

The rise of Big Data in recent years brings many challenges to modern statistical analysis and modeling. In toxicogenomics, the advancement of high-throughput screening technologies facilitates the generation of massive amount of biological data, a big data phenomena in biomedical science. Yet, researchers still heavily rely on key word search and/or literature review to navigate the databases and analyses are often done in rather small-scale. As a result, the rich information of a database has not been fully utilized, particularly for the information embedded in the interactive nature between data points that are largely ignored and buried. For the past …

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Paddling A Trail, Erin Jennings Gilleece Dec 2015

Paddling A Trail, Erin Jennings Gilleece

Graduate Theses and Dissertations

Paddling A Trail documents construction of the first water trail in Arkansas. The 15 minute film is narrated by Arkansas Canoe Club Conservation Chair Debbie Doss. It follows Doss, and other volunteers as they mark the Wattensaw Bayou Trail in Hazen, Arkansas. The film is co-narrated by Kristen Bartlow of the Arkansas Game and Fish Commission. The footage was shot over three days, in two different locations. These were the White River in Northwest Arkansas and Wattensaw Bayou in Hazen, AR. The film illustrates the positive role trails can have on the environment and local economies. More importantly, the film …

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Dark Matter Halo Concentration And The Evolution Of Spiral Structure In N-Body, Barred Spiral Galaxies, Jazmin Esmeralda Berlanga Medina Dec 2015

Dark Matter Halo Concentration And The Evolution Of Spiral Structure In N-Body, Barred Spiral Galaxies, Jazmin Esmeralda Berlanga Medina

Graduate Theses and Dissertations

Motivated by the evidence of relationships between pitch angle (the tightness of spiral arm structure in the disk), P, and various indicators of central mass concentration, as well as the theoretical relationship between halo mass concentration and the density of visible matter in the central part of the galaxy, we look at a possible relationship between P and cvir (the virial concentration of the dark matter halo) in N-body simulations of barred, spiral galaxies. We also look at the evolution of pitch angle over time in higher temporal resolution than any data currently available in the literature. We find that …

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Mopeye: Monitoring Per-App Network Performance With Zero Measurement Traffic, Daoyuan Wu, Weichao Li, Rocky K. C. Chang, Debin Gao Dec 2015

Mopeye: Monitoring Per-App Network Performance With Zero Measurement Traffic, Daoyuan Wu, Weichao Li, Rocky K. C. Chang, Debin Gao

Research Collection School Of Computing and Information Systems

Mobile network performance measurement is important for understanding mobile user experience, problem diagnosis, and service comparison. A number of crowdsourcing measurement apps (e.g., MobiPerf and Netalyzr) have been embarked for the last few years. Unlike existing apps that use active measurement methods, we employ a novel passive-active approach to continuously monitor per-app network performance on unrooted smartphones without injecting additional network traffic. By leveraging the VpnService API on Android, MopEye, our measurement app, intercepts all network traffic and then relays them to their destinations using socket APIs. Therefore, not only MopEye can measure the round-trip time accurately, it can do …

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Neutrino Signatures In Terrestrial Detectors From Two- And Three-Dimensional Core-Collapse Supernovae Simulations, Tanner Brooks Devotie Dec 2015

Neutrino Signatures In Terrestrial Detectors From Two- And Three-Dimensional Core-Collapse Supernovae Simulations, Tanner Brooks Devotie

Masters Theses

Core-collapse supernovae (CCSNe) are driven by neutrino emission and are the most prodigious sources of neutrinos in the Universe. Importantly, the neutrino radiation from CCSNe is emitted from deep in the explosion and can provide information about physical processes taking place in the newly-born neutron star at the heart of the event. We examine the four-flavor (i.e. νe, νe, νx and νx) [electron, muon and tau neutrinos along with their anti-matter counterparts] signature of CCSNe neutrino emission in various neutrino detector types. We use data from the multidimensional Chimera (Lentz et al., 2015) …

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Two Nucleon Systems At M(Pi) Similar To 450 Mev From Lattice Qcd, Kostas Orginos, Assumpta Parreño, Martin J. Savage, Silas R. Beane, Et Al. Dec 2015

Two Nucleon Systems At M(Pi) Similar To 450 Mev From Lattice Qcd, Kostas Orginos, Assumpta Parreño, Martin J. Savage, Silas R. Beane, Et Al.

Arts & Sciences Articles

Nucleon-nucleon systems are studied with lattice quantum chromodynamics at a pion mass of m(pi) similar to 450 MeV in three spatial volumes using n(f) = 2 + 1 flavors of light quarks. At the quark masses employed in this work, the deuteron binding energy is calculated to be B-d = 14.4(-2.6)(+3.2) MeV, while the dineutron is bound by B-nn = 12.5(-5.0)(+3.0) MeV. Over the range of energies that are studied, the S-wave scattering phase shifts calculated in the S-1(0) and S-3(1)-D-3(1) channels are found to be similar to those in nature, and indicate repulsive short-range components of the interactions, consistent …

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Evaluation Of Large‑Scale Meteorological Patterns Associated With Temperature Extremes In The Narccap Regional Climate Model Simulations, Paul C. Loikith, Duane E. Waliser, Huikyo Lee, J. David Neelin, Benjamin Lintner, Seth Mcginnis, Linda Mears, Jinwon Kim Dec 2015

Evaluation Of Large‑Scale Meteorological Patterns Associated With Temperature Extremes In The Narccap Regional Climate Model Simulations, Paul C. Loikith, Duane E. Waliser, Huikyo Lee, J. David Neelin, Benjamin Lintner, Seth Mcginnis, Linda Mears, Jinwon Kim

Geography Faculty Publications and Presentations

Large-scale meteorological patterns (LSMPs) associated with temperature extremes are evaluated in a suite of regional climate model (RCM) simulations contributing to the North American Regional Climate Change Assessment Program. LSMPs are characterized through composites of surface air temperature, sea level pressure, and 500 hPa geopotential height anomalies concurrent with extreme temperature days. Six of the seventeen RCM simulations are driven by boundary conditions from reanalysis while the other eleven are driven by one of four global climate models (GCMs). Four illustrative case studies are analyzed in detail. Model fidelity in LSMP spatial representation is high for cold winter extremes near …

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Electrochemical Formation Of One-Dimensional Metal Nanostructures Across Microgaps Electrodes For Resistive Switching And Optical Sensing Applications., Nidhi Shah Dec 2015

Electrochemical Formation Of One-Dimensional Metal Nanostructures Across Microgaps Electrodes For Resistive Switching And Optical Sensing Applications., Nidhi Shah

Electronic Theses and Dissertations

This dissertation focuses on the electrochemical formation of one-dimensional (1D) Ag nanostructures (in particular nanowires and nanochains) directly on electrode surfaces or gap of two electrodes. Ag nanowires (NWs) and nanorods (NRs) grow directly on glass/indium tin oxide (ITO) surfaces from electrode-attached Au nanoparticle seeds in the presence of cetyltrimethylammonium bromide (CTAB) at appropriate potentials with a 5-15 % yield and the average length ranging from 100 nm to 3 µm for growth times of 30 to 120 min. This method failed when trying to grow Ag NRs/NWs across 5 µm Au electrode gaps. Interestingly, applying voltage in air leads …

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Spreading Speeds And Traveling Waves In Some Population Models., Quancheng Meng Dec 2015

Spreading Speeds And Traveling Waves In Some Population Models., Quancheng Meng

Electronic Theses and Dissertations

Virtually every ecosystem has been invaded by exotic organisms with potentially drastic consequences for the native fauna or flora. Studying the forms and rates of invading species has been an important topic in spatial ecology. We investigate two two-species competition models with Allee effects in the forms of reaction-diffusion equations and integro-difference equations. We discuss the spatial transitions from a mono-culture equilibrium to a coexistence equilibrium or a different mono-culture equilibrium in these models. We provide formulas for the spreading speeds based on the linear determinacy and show the results on the existence of traveling waves. We also study a …

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Multiple Instance Fuzzy Inference., Amine Ben Khalifa Dec 2015

Multiple Instance Fuzzy Inference., Amine Ben Khalifa

Electronic Theses and Dissertations

A novel fuzzy learning framework that employs fuzzy inference to solve the problem of multiple instance learning (MIL) is presented. The framework introduces a new class of fuzzy inference systems called Multiple Instance Fuzzy Inference Systems (MI-FIS). Fuzzy inference is a powerful modeling framework that can handle computing with knowledge uncertainty and measurement imprecision effectively. Fuzzy Inference performs a non-linear mapping from an input space to an output space by deriving conclusions from a set of fuzzy if-then rules and known facts. Rules can be identified from expert knowledge, or learned from data. In multiple instance problems, the training data …

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No Major Changes On Paleoclimate And Paleoenvironment Across The Eocene–Oligocene Transition In The Central Rocky Mountains, Sara Ayyash Dec 2015

No Major Changes On Paleoclimate And Paleoenvironment Across The Eocene–Oligocene Transition In The Central Rocky Mountains, Sara Ayyash

Earth & Environmental Sciences Theses

Earth’s climate has experienced dramatic cooling during the Eocene-Oligocene Transition (EOT) based on well-constrained marine geological records, however, a consensus on the terrestrial responses to this event has not been reached. The White River Formation in the central Rocky Mountains, western U.S.A., is a well-dated stratigraphic unit covering the EOT. The formation contains tuffaceous mudrock and sandstone that were deposited in fluvial and eolian depositional environments. Here I study oxygen isotope ratios and clumped isotope temperatures of carbonate cements and bulk organic carbon isotope ratios in order to reconstruct the paleoenvironment and paleoclimate across the EOT. These carbonate cements were …

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Bimetallic-Waveguide Coupled Sensors For Tunable Plasmonic Devices, Kunal K. Tiwari Dec 2015

Bimetallic-Waveguide Coupled Sensors For Tunable Plasmonic Devices, Kunal K. Tiwari

Physics Dissertations

Surface plasmon resonance (SPR) has been a widely used optical technique for the real time and label free sensing applications in biomedicine, homeland security, food safety, environmental monitoring, etc. Surface plasmons (SPs) being extremely sensitive to the surrounding media, their characteristics can be modulated by tuning their dielectric environment. The unique property of the nematic liquid crystalline materials that their dielectric constant can be tuned by externally applied electric fields formed the basis for development of tunable plasmonic sensor for monitoring changes at metal/dielectric interfaces. Even though sensors with high sensitivity are available, it remains highly desirable to enhance sensor …

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The Search For Exomoon Radio Emissions, Joaquin P. Noyola Dec 2015

The Search For Exomoon Radio Emissions, Joaquin P. Noyola

Physics Theses

The field of exoplanet detection has seen many new developments since the discovery of the first exoplanet. Observational surveys by the NASA Kepler Mission and several other instrument have led to the confirmation of over 1900 exoplanets, and several thousands of exoplanet potential candidates. All this progress, however, has yet to provide the first confirmed exomoon. Since all previous attempts to discover exomoons have failed, a novel method to detect them is proposed in this dissertation, which describes development of the method and its applications to select the best exomoon candidates for observational searches. The main goal of these searches …

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Controlled Hydrosilylations Of Carbonyl Compounds And Computational Investigations Of A Hydride Shuttle Mechanism For Alkene Hydrosilylation, Gabriela Trog Dec 2015

Controlled Hydrosilylations Of Carbonyl Compounds And Computational Investigations Of A Hydride Shuttle Mechanism For Alkene Hydrosilylation, Gabriela Trog

Chemistry & Biochemistry Theses

Chapter 1 describes tandem dual hydrosilylations of α,β-unsaturated enals. Hydrosilylations of both carbonyl compounds and alkenes have been utilized to create chiral alcohols. Tandem dual hydrosilylations (TDH) of α,β-unsaturated carbonyl compounds create five-membered oxasilacycles that can be further converted to 1,3- diols, which are a common structural motif in the polyketide natural product family. We present preliminary data and a substrate scope for the formation of these oxasilacycles en route to the 1,3-diol compounds. Chapter 2 describes hydrosilylations of esters that result in silyl acetals. The silyl acetals are chemical synthons of the corresponding aldehyde. This reaction can be coupled …

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Evaluation Of Activated Carbon As A Commercial Drug Disposal Product Using Liquid Chromatography–Tandem Mass Spectrometry, Veronica B. Waybright Dec 2015

Evaluation Of Activated Carbon As A Commercial Drug Disposal Product Using Liquid Chromatography–Tandem Mass Spectrometry, Veronica B. Waybright

Chemistry & Biochemistry Theses

At present, pharmaceuticals, synthetic organic compounds, and endocrine disrupting compounds are ubiquitous in our environment. These have been introduced by consumers and manufacturers directly and indirectly for decades. There is plenty of published literature addressing the presence of these compounds, the development of newer and more sensitive techniques to detect them at low concentrations, as well as studies showing their effects in the environment and in human health. However, these studies are based on the measurement and detection of these compounds after the fact; and even though some have addressed the need to decrease these pollutants in the environment, procedures …

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New Conductometric Detection Methods For Sensitive Ion Chromatographic Measurement Of Weak Electrolytes, Hongzhu Liao Dec 2015

New Conductometric Detection Methods For Sensitive Ion Chromatographic Measurement Of Weak Electrolytes, Hongzhu Liao

Chemistry & Biochemistry Theses

Since Suppressed conductometric anion chromatography (SCAC) was proposed in the mid-1970s, SCAC has become a widely used tool for the determination of anion species in aqueous samples. Its application ranges from trace analysis in semiconductor manufacture to pharmaceutical analysis. This dissertation primarily focuses on three different projects on the conductometric determination of weak acids. Other work carried out during the same period both involved SCAC for the determination of anion composition of açaí Extracts and on the unusual ion exchange behavior of myo‐inositol phosphates. SCAC responds poorly and nonlinearly to weak acids, because they only ionize partially and the degree …

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Structure-Activity Relationships Of Ruthenium(Ii) Polypyridyl Complexes With Redox-Active Intercalating Ligands: Correlation Between Redox Activity, Dna Cleavage Capability And Cytotoxicity, Eugenia Soyo Narh Dec 2015

Structure-Activity Relationships Of Ruthenium(Ii) Polypyridyl Complexes With Redox-Active Intercalating Ligands: Correlation Between Redox Activity, Dna Cleavage Capability And Cytotoxicity, Eugenia Soyo Narh

Chemistry & Biochemistry Theses

The investigation and development of transition metal complexes as cancer chemotherapeutics has gained a lot of interest in the past few decades and has become a promising area of research. Metal complexes of platinum and ruthenium in particular that have demonstrated success as anticancer drugs or are under exploration currently for clinical use are highlighted in Chapter 1. Chapter 2 describes studies undertaken to understand the neurotoxicity of ruthenium(II) polypyridyl complexes (RPCs), including toxicity in mice and inhibition of the enzyme acetylcholinesterase (AChE), as previous work by Dwyer demonstrated that RPCs could be acutely toxic in mice, presumably due to …

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The Effects Of Prompted Tutoring On An Emporium Model Math Course, Juliette Michelle Young Dec 2015

The Effects Of Prompted Tutoring On An Emporium Model Math Course, Juliette Michelle Young

Honors Theses

My research goal is to investigate how specific prompting of students would affect their involvement and progress in an emporium developmental math course. With the aim of increasing the students’ involvement and progress I tested a method that was in tended to increase students’ perceived connectedness with the classroom and promote the use of the available tutors and teachers. I monitored consenting students’ progress in the Spring 2015 courses and sent emails to students who met any one of three different criterion: (1) If the students time investment was below a threshold. (2) If the student’s mastery pace was less …

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High-Resolution Correlation Of A Time-Bounded Unit Of The Pisco Formation, Peru, Daniel J. O'Hare Dec 2015

High-Resolution Correlation Of A Time-Bounded Unit Of The Pisco Formation, Peru, Daniel J. O'Hare

Loma Linda University Electronic Theses, Dissertations & Projects

Correlation of beds in the Pisco Basin across significant distances is problematic and has not yet been effectively achieved. I chose to examine an interval bounded by two time markers, an 40Ar/39Ar-dated white tuff at the base and an 40Ar/39Ar-dated tuff couplet at the top. This interval was chosen because of the continuity and excellent exposure of the tuff beds at six distinct locations in a linear transect 30 km long. Correlation of units was achieved through 40Ar/39Ar dating, lithology, sedimentary structures, and magnetic susceptibility. The vertical and lateral variability in lithology, fossil assemblages, structures, and sequences was examined in …

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Soft-Sediment Deformation And Dune Collapse In The Navajo Sandstone, Colby Ford Dec 2015

Soft-Sediment Deformation And Dune Collapse In The Navajo Sandstone, Colby Ford

Loma Linda University Electronic Theses, Dissertations & Projects

The Canyon Overlook Trail of Zion National Park follows an outcrop of Navajo Sandstone, which displays a uniquely well-exposed assemblage of features associated with failure of the lee face of a large eolian dune, and run-out over an expanse of interdune sediments downwind of that bedform. Exposed features include dramatic folds in the interdune succession and a stacked series of thrust sheets incorporating both interdune and overlying dune deposits. Thrust surfaces display consistent strikes, parallel to those of undeformed foresets, and incorporate zones of brittle failure and fluid deformation, including folds overturned in the direction of foreset dip. These features …

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Influence Of Shelling Temperature And Time On The Optical And Structural Properties Of Cuins2/Zns Quantum Dots, Colette Robinson Dec 2015

Influence Of Shelling Temperature And Time On The Optical And Structural Properties Of Cuins2/Zns Quantum Dots, Colette Robinson

Graduate Theses and Dissertations

CIS/ZnS core/shell QDs are an important class of nanomaterials for optoelectronic, photovoltaic and photoluminescence applications. They consist of lower toxicity materials than the prototypical II-VI Cd-based QDs and show long fluorescence lifetimes, which generates prospective in biological imaging applications. It is vital to develop reproducible synthetic methods for this new class of nanomaterials in order to maintain small sizes with high QYs. CIS core QDs have been shelled with ZnS at various temperatures from 90-210°C for reaction times ranging from 20-140 minutes to examine the role of thermodynamics and kinetics on the shell growth. Using HR-TEM and ICP-MS, it was …

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Modifying A Cow-Calf Biophysical Simulation Model For Analyses Of Alternative Enterprises, Jennifer L. Lutes Dec 2015

Modifying A Cow-Calf Biophysical Simulation Model For Analyses Of Alternative Enterprises, Jennifer L. Lutes

Graduate Theses and Dissertations

Cow-calf producers in the United States, tasked with providing beef calves for the beef industry, have had a multitude of difficulties to overcome in recent years. Producers in northwest Arkansas were negatively impacted by high hay prices coupled with low beef cattle market prices due to severe drought experienced in portions of 2010, 2011, and 2012. During this time they also faced high grain prices, due to a record low harvest, combined with portions of the corn harvest diverted from human and animal feed to ethanol production. Tight lending policies of this time, reminiscent of the housing market crash in …

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Fluid Uptake Of The Goddard Shale In Southeastern Oklahoma, Usa, Paul Huggins Dec 2015

Fluid Uptake Of The Goddard Shale In Southeastern Oklahoma, Usa, Paul Huggins

Earth & Environmental Sciences Theses

The South Central Oklahoma Oil Province is the current play for the Goddard shale and is also the main field for the underlying Woodford Formation. As of September 2015, an estimated 40 wells have been drilled to evaluate and produce the Goddard shale in the southeastern portion of the Anadarko Basin. With companies reporting initial production rates ranging from 1,000 boe/d to nearly 2,000 boe/d and 30 day reports averaging around 800 boe/d, the amount of recovery from this tight shale reservoir has exceptional potential. Continental Resources Inc. estimates a gross recovery of 940,000 boe per lateral well. Understanding the …

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Characterization Of The Constituent Mineral Components Of North African Surface Dust Samples Utilizing Computer Controlled Scanning Electron Microscopy (Ccsem), Zakariah Edward Sabatka Dec 2015

Characterization Of The Constituent Mineral Components Of North African Surface Dust Samples Utilizing Computer Controlled Scanning Electron Microscopy (Ccsem), Zakariah Edward Sabatka

Earth & Environmental Sciences Theses

Analysis of the constituent mineral components of surface dusts/soils from Chad-Niger region, North Africa, was undertaken by computer controlled scanning electron microscopy (CCSEM) to determine if differences in composition could be used for source attribution to distinguish windblown material from different contributing source areas. A total of 11 surficial samples were selected for analysis by computer controlled scanning electron microscopy (CCSEM). These samples were from two different geographic locations in the Chad-Niger region. CCSEM analysis generates data on individual dust particles that includes: particle size, shape, and chemical composition. This type of particle characterization used a Scanning Electron Microscope (SEM) …

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Regional Stratigraphy Of The Marble Falls Formation And Underlying Late Mississippian To Early Pennsylvanian Deposits, Fort Worth Basin, North-Central Texas, Usa, Beau Daniel Berend Dec 2015

Regional Stratigraphy Of The Marble Falls Formation And Underlying Late Mississippian To Early Pennsylvanian Deposits, Fort Worth Basin, North-Central Texas, Usa, Beau Daniel Berend

Earth & Environmental Sciences Theses

The Early Pennsylvanian Marble Falls Formation in the Fort Worth Basin (FWB) of North-Central Texas was deposited in a broad carbonate ramp system during the initial stages of Ouachita orogenesis. It extends across an area of more than 15,000 square miles and comprises an assortment of facies that vary considerably across the region due to high-frequency sea-level fluctuations. The Marble Falls has been studied extensively in outcrop around the periphery of the Llano Uplift where it was informally divided into lower and upper members separated by a regional unconformity representing the Morrowan-Atokan boundary. A sequence of the Marble Falls Formation …

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Hierarchical Segmentation Of The Malawi Rift: The Influence Of Inherited Lithospheric Heterogeneity And Kinematics In The Evolution Of Continental Rifts, Daniel A. Lao-Davila, Haifa S. Al-Salmi, Mohamed G. Abdel Salam, Estella A. Atekwana Dec 2015

Hierarchical Segmentation Of The Malawi Rift: The Influence Of Inherited Lithospheric Heterogeneity And Kinematics In The Evolution Of Continental Rifts, Daniel A. Lao-Davila, Haifa S. Al-Salmi, Mohamed G. Abdel Salam, Estella A. Atekwana

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We used detailed analysis of Shuttle Radar Topography Mission-digital elevation model and observations from aeromagnetic data to examine the influence of inherited lithospheric heterogeneity and kinematics in the segmentation of largely amagmatic continental rifts. We focused on the Cenozoic Malawi Rift, which represents the southern extension of the Western Branch of the East African Rift System. This north trending rift traverses Precambrian and Paleozoic-Mesozoic structures of different orientations. We found that the rift can be hierarchically divided into first-order and second-order segments. In the first-order segmentation, we divided the rift into Northern, Central, and Southern sections. In its Northern Section, …

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Modeling Of Gas Production From Shale Reservoirs Considering Multiple Transport Mechanisms, Chaohua Guo, Mingzhen Wei, Hong Liu Dec 2015

Modeling Of Gas Production From Shale Reservoirs Considering Multiple Transport Mechanisms, Chaohua Guo, Mingzhen Wei, Hong Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Gas transport in unconventional shale strata is a multi-mechanism-coupling process that is different from the process observed in conventional reservoirs. In micro fractures which are inborn or induced by hydraulic stimulation, viscous flow dominates. And gas surface diffusion and gas desorption should be further considered in organic nano pores. Also, the Klinkenberg effect should be considered when dealing with the gas transport problem. In addition, following two factors can play significant roles under certain circumstances but have not received enough attention in previous models. During pressure depletion, gas viscosity will change with Knudsen number; and pore radius will increase when …

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Use Of Cubic B-Spline In Approximating Solutions Of Boundary Value Problems, Maria Mungia, Dambaru Bhatta Dec 2015

Use Of Cubic B-Spline In Approximating Solutions Of Boundary Value Problems, Maria Mungia, Dambaru Bhatta

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Here we investigate the use of cubic B-spline functions in solving boundary value problems. First, we derive the linear, quadratic, and cubic B-spline functions. Then we use the cubic B-spline functions to solve second order linear boundary value problems. We consider constant coefficient and variable coefficient cases with non-homogeneous boundary conditions for ordinary differential equations. We also use this numerical method for the space variable to obtain solutions for second order linear partial differential equations. Numerical results for various cases are presented and compared with exact solutions.

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Sparse Aperture Speckle Interferometry Telescope Active Optics Control System, Matthew Clause Dec 2015

Sparse Aperture Speckle Interferometry Telescope Active Optics Control System, Matthew Clause

Master's Theses

A conventional large aperture telescope required for binary star research is typically cost prohibitive. A prototype active optics system was created and fitted to a telescope frame using relatively low cost components. The active optics system was capable of tipping, tilting, and elevating the mirrors to align reflected star light. The low cost mirror position actuators have a resolution of 31 nm, repeatable to within 16 nm. This is accurate enough to perform speckle analysis for the visible light spectrum. The mirrors used in testing were not supported with a whiffletree and produced trefoil-like aberrations which made phasing two mirrors …

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An Integrated Drought Index (Idi) Incorporating Physical And Social Aspects, Rebecca L. Lanier Dec 2015

An Integrated Drought Index (Idi) Incorporating Physical And Social Aspects, Rebecca L. Lanier

Master's Theses

The purpose of this research was to determine significant bio-physical (physical and environmental) and social variables that can be integrated into a drought index to predict areas susceptible to drought. Severe drought events are capable of causing millions of dollars in damage. The 1988 drought caused the United States approximately $40 billion in damage. Drought forecasting, modeling, and detection have, therefore, become imperative to understand the social, economic and environmental impacts of droughts, and also to explore how these impacts play a role in the occurrence of a drought. A number of drought indices widely used in the U.S. rely …

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