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2016

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Measurement Units In R, Edzer Pebesma, Thomas Mailund, James Hiebert Dec 2016

Measurement Units In R, Edzer Pebesma, Thomas Mailund, James Hiebert

The R Journal

We briefly review SI units, and discuss R packages that deal with measurement units, their compatibility and conversion. Built upon udunits2 and the UNIDATA udunits library, we introduce the package units that provides a class for maintaining unit metadata. When used in expression, it automatically converts units, and simplifies units of results when possible; in case of incompatible units, errors are raised. The class flexibly allows expansion beyond predefined units. Using units may eliminate a whole class of potential scientific programming mistakes. We discuss the potential and limitations of computing with explicit units.

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Tigris: An R Package To Access And Work With Geographic Data From The Us Census Bureau, Kyle Walker Dec 2016

Tigris: An R Package To Access And Work With Geographic Data From The Us Census Bureau, Kyle Walker

The R Journal

TIGER/Line shapefiles from the United States Census Bureau are commonly used for the mapping and analysis of US demographic trends. The tigris package provides a uniform interface for R users to download and work with these shapefiles. Functions in tigris allow R users to request Census geographic datasets using familiar geographic identifiers and return those datasets as objects of class "Spatial*DataFrame". In turn, tigris ensures consistent and high-quality spatial data for R users’ cartographic and spatial analysis projects that involve US Census data. This article provides an overview of the functionality of the tigris package, and concludes with an applied …

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Mixtox: An R Package For Mixture Toxicity Assessment, Xiang-Wei Zhu, Jian-Yi Chen Dec 2016

Mixtox: An R Package For Mixture Toxicity Assessment, Xiang-Wei Zhu, Jian-Yi Chen

The R Journal

Mixture toxicity assessment is indeed necessary for humans and ecosystems that are continually exposed to a variety of chemical mixtures. This paper describes an R package, called mixtox, which offers a general framework of curve fitting, mixture experimental design, and mixture toxicity prediction for practitioners in toxicology. The unique features of mixtox include: (1) constructing a uniform table for mixture experimental design; and (2) predicting toxicity of a mixture with multiple components based on reference models such as concentration addition, independent action, and generalized concentration addition. We describe the various functions of the package and provide examples to illustrate their …

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Water: Tools And Functions To Estimate Actual Evapotranspiration Using Land Surface Energy Balance Models In R, Guillermo Federico Olmedo, Samuel Ortega-Farías, Daniel De La Fuente-Sáiz, David Fonseca- Luego, Fernando Fuentes-Peñailillo Dec 2016

Water: Tools And Functions To Estimate Actual Evapotranspiration Using Land Surface Energy Balance Models In R, Guillermo Federico Olmedo, Samuel Ortega-Farías, Daniel De La Fuente-Sáiz, David Fonseca- Luego, Fernando Fuentes-Peñailillo

The R Journal

The crop water requirement is a key factor in the agricultural process. It is usually estimated throughout actual evapotranspiration (ETa). This parameter is the key to develop irrigation strategies, to improve water use efficiency and to understand hydrological, climatic, and ecosystem processes. Currently, it is calculated with classical methods, which are difficult to extrapolate, or with land surface energy balance models (LSEB), such as METRIC and SEBAL, which are based on remote sensing data. This paper describes water, an open implementation of LSEB. The package provides several functions to estimate the parameters of the LSEB equation from satellite data …

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Finnish Teacher Collaboration: The Behaviors, Learning, And Formality Of Teacher Collaboration, Bruce H. Eschler Dec 2016

Finnish Teacher Collaboration: The Behaviors, Learning, And Formality Of Teacher Collaboration, Bruce H. Eschler

Theses and Dissertations

Finnish teachers continue to receive significant attention among educators, educational leaders, and policy makers in the United States and around the globe. In addition, teacher collaboration continues to receive support as a meaningful part of teacher work and practice. Teacher collaboration is frequently described in various ways within different contexts. This study aims to: (a) better understand the nature of Finnish teacher collaboration by examining three teacher collaboration behaviors (sharing information and knowledge, planning, and problem-solving); (b) explore the extent to which Finnish teacher collaboration is formal (or school-required) collaboration and informal (or voluntary) collaboration; and (c) investigate …

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The Riemann Hypothesis, Danny Allen, Kyle Bonetta-Martin, Elizabeth Codling, Simon Jefferies Dec 2016

The Riemann Hypothesis, Danny Allen, Kyle Bonetta-Martin, Elizabeth Codling, Simon Jefferies

The Plymouth Student Scientist

This literature review provides a brief discussion of the Riemann Hypothesis, a conjecture regarding the location of the zeros on the Riemann zeta function. We also look at the implications of solving the hypothesis, and investigate historical attempts to solve the conjecture.

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Analysis Of Manufacturing Parameters On The Shear Strength Of Aluminium/Gfrp Co-Cured And Adhesively Bonded Single-Lap Joints, Ashley Reburn Dec 2016

Analysis Of Manufacturing Parameters On The Shear Strength Of Aluminium/Gfrp Co-Cured And Adhesively Bonded Single-Lap Joints, Ashley Reburn

The Plymouth Student Scientist

Due to the increased application of composite materials in recent years, the process of joining composites to metals has become a key area of interest. As a result, methods to increase the strength of composite-to-metal joints are highly sought after. Since the mechanical behaviour of composite-to-metal joints depends on many manufacturing parameters. An experimental and numerical study into the shear strength behaviour of GFRP-to-aluminium single-lap joints was performed to investigate the effect of four manufacturing parameters, with the aim of optimising shear strength. For one manufacturing parameter, a relatively new joining process, co-curing, is studied, and results are benchmarked against …

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How Do Designers Of The Built Environment Attempt To Make Ecological Sustainability Sensory Legible?, Carly L. Bartow Dec 2016

How Do Designers Of The Built Environment Attempt To Make Ecological Sustainability Sensory Legible?, Carly L. Bartow

Architecture Undergraduate Honors Theses

This paper attempts to provide a theoretical framework for making ecosystem function and ecologically sustainable design more perceptible or sensible to people through architecture and the built environment. Design features of the Bertschi School Science Wing and the Bullitt Center in Seattle, Washington are incorporated to illustrate the sensory legibility of ecological sustainability criteria.The criteria are available to designers to help educate a building's occupants on environmentally sustainable design and motivate more sustainable behavior.

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Effects Of Digital-Based Math Fluency Interventions On Learners With Math Difficulties: A Review Of The Literature, Lauren E. Cozad, Paul J. Riccomini Dec 2016

Effects Of Digital-Based Math Fluency Interventions On Learners With Math Difficulties: A Review Of The Literature, Lauren E. Cozad, Paul J. Riccomini

The Journal of Special Education Apprenticeship

Mathematical proficiency serves as a foundation for student success in the classroom and real world. One component of mathematical proficiency is fluency with basic facts. Frequently, students with mathematics difficulties struggle to become proficient and fluent in the four basic operations. Interventions are available to help develop and promote fluency for students. Digital-based interventions, such as programs on computers or tablet applications, are one avenue by which students are able to acquire and maintain fluency. These digital tools are becoming increasingly more common and available in today’s classroom. Eight studies on digital-based fact fluency were identified through a systematic search …

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Effects Of Tli- Versus Nwea-Interim Assessment On Academic Achievement Of Sixth- And Seventh-Grade Students, Walt Davis Dec 2016

Effects Of Tli- Versus Nwea-Interim Assessment On Academic Achievement Of Sixth- And Seventh-Grade Students, Walt Davis

College of Education Dissertations

This project focused on two online providers, The Learning Institute (TLI) and Northwest Evaluation Association (NWEA). The purpose of this dissertation was to provide additional research concerning the effects of interim assessments (TLI versus NWEA) and gender on literacy and mathematics achievement for students in Grades 6 and 7 in Northwest Arkansas. Of the four included school districts, two used TLI and two used NWEA as their interim assessment. For all four hypotheses, the independent variables were gender and interim assessment type. In the first and second hypotheses, the dependent variable was literacy achievement as measured by student performance on …

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Civil Rights In A Desegregating America, Nicholas Stephanopoulos Dec 2016

Civil Rights In A Desegregating America, Nicholas Stephanopoulos

Articles

No abstract provided.

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Monotonicity Properties Of Stochastic Kriging Metamodels And Related Applications, Bing Wang Dec 2016

Monotonicity Properties Of Stochastic Kriging Metamodels And Related Applications, Bing Wang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Stochastic kriging (SK) and stochastic kriging with gradient estimators (SKG) are popular approaches to approximate complex simulation models because of their ability to replace the expensive simulation outputs by metamodel values. Obtaining an accurate SK/SKG metamodel is highly desirable in practice. This dissertation studies the monotonicity properties of the mean squared error (MSE) of optimal SK and SKG predictors. In particular, we show that in both SK and SKG, the MSEs of the corresponding optimal predictors are non-increasing functions of the numbers of design points. Based on these findings, we design an adaptive sequential sampling approach to obtain SK/SKG predictors …

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Characterization Of Structural Defects In Wide Band-Gap Compound Materials For Semiconductor And Opto-Electronic Applications, Ouloide Yannick Goue Dec 2016

Characterization Of Structural Defects In Wide Band-Gap Compound Materials For Semiconductor And Opto-Electronic Applications, Ouloide Yannick Goue

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Single crystals of binary and ternary compounds are touted to replace silicon for specialized applications in the semiconductor industry. However, the relative high density of structural defects in those crystals has hampered the performance of devices built on them. In order to enhance the performance of those devices, structurally perfect single crystals must be grown. The aim of this thesis is to investigate the interplay between crystal growth process and crystal quality as well as structural defect types and transport property. To this end, the thesis is divided into two parts. The first part provides a general review of the …

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A Data Driven Design Methodology For Ss Dyads And Its Application To Unified Synthesis Of Planar, Spherical And Spatial Linkages, Xin Ge Dec 2016

A Data Driven Design Methodology For Ss Dyads And Its Application To Unified Synthesis Of Planar, Spherical And Spatial Linkages, Xin Ge

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

This research deals with a general kinematic synthesis problem of how to generate the motion of a spatial platform subject to one or more spherical con- straints. Each spherical constraint can be modeled by a SS dyad, which is a spatial two-link kinematic chain connected by two spherical (S) joints. It defines a five-degree-of-freedom motion of the end link such that a point stays on the surface of a sphere. A spherical constraint degenerates into a plane constraint when the radius of the sphere becomes infinite. In this way, a plane constraint is considered as a special case of a …

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Task Scheduling In Modern Data Center: Task Placement And Resource Allocation, Li Shi Dec 2016

Task Scheduling In Modern Data Center: Task Placement And Resource Allocation, Li Shi

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

In modern data centers, the wide use of virtualization techniques has enabled dynamic resource allocation in the form of virtual machines and virtual networks. With such an ability, scheduling tasks, including both computing tasks and data transfer tasks, comprises (a) placing tasks on servers or network paths and (b) allocating a certain amount of resources to each task. In such a context, minimizing the completion time of the tasks, as a critical goal on many task processing platforms, requires joint consideration of both task placement and resource allocation. While many approaches have been proposed in the area of scheduling tasks …

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Uncertainty Quantification For Physical And Numerical Diffusion Models In Inertial Confinement Fusion Simulations, Verinder S. Rana Dec 2016

Uncertainty Quantification For Physical And Numerical Diffusion Models In Inertial Confinement Fusion Simulations, Verinder S. Rana

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

This thesis concerns simulations of Inertial Confinement Fusion. Inertial confinement is carried out in a large scale facility at National Ignition Facility. The experiments have failed to reproduce design calculations, and so uncertainty quantification of calculations is an important asset. Uncertainties can be classified as aleatoric or epistemic. This thesis is concerned with aleatoric uncertainty quantification. Among the many uncertain aspects that affect the simulations, we have narrowed our study of possible uncertainties. The first source of uncertainty we present is the amount of pre-heating of the fuel done by hot electrons. The second source of uncertainty we consider is …

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Turbulent Mixing In Richtmyer-Meshkov Instability Using Front-Tracking, Pooja Rao Dec 2016

Turbulent Mixing In Richtmyer-Meshkov Instability Using Front-Tracking, Pooja Rao

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Turbulent mixing from hydrodynamical instabilities, such as Richtmyer-Meshkov (RMI) and Rayleigh-Taylor (RTI) instabilities, plays a critical role in numerous applications ranging from performance degradation in inertial confinement capsules to supernova explosions. At high Reynolds numbers (Re), for which experimental data is not available, numerical simulations are paramount in studying these instabilities. However, the algorithmic differences due to differences in numerical modeling often give solutions that are converged but not unique, that is, different codes converge to different solutions. Thus, to establish the credibility of the simulation in an objective manner, it is necessary to fulfill three main requirements: (1) verification …

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Numerical Modeling Of Hydrodynamic Instabilities And Their Impact On Mix In Inertial Confinement Fusion, Jeremy Melvin Dec 2016

Numerical Modeling Of Hydrodynamic Instabilities And Their Impact On Mix In Inertial Confinement Fusion, Jeremy Melvin

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The simulation campaign to model Inertial Confinement Fusion (ICF) capsules has come a long way since experiments with the potential to achieve net energy gain began in 2010. A remaining area of uncertainty is the modeling of instability growth and mixing of ablator material into the core, degrading the capsules. We explore the instability growth by applying techniques that have led to a proven track record of validation: the addition of a front tracking (FT) algorithm and physical diffusion models. For the first time, we have integrated our FT algorithm through an API into an external Rad-Hydro code FLASH, from …

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Institutional Change In Undergraduate Education At A Research University: The Stony Brook Undergraduate Colleges, Donna M. Di Donato Dec 2016

Institutional Change In Undergraduate Education At A Research University: The Stony Brook Undergraduate Colleges, Donna M. Di Donato

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

This qualitative case study concentrates on the evolution of undergraduate education at Stony Brook University, with particular focus on the establishment and continuity of the Undergraduate College program. The Undergraduate Colleges represent the most broadly imagined undertaking in undergraduate education in Stony Brook’s history and, therefore, is a good case study for the exploration of the topic of institutionalizing change and programmatic persistence. The Undergraduate Colleges marked the first attempt to establish a formal introduction to Stony Brook as a research university to all incoming freshmen, involving both academic and student affairs components and, most importantly, faculty. Program architects contended …

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Influence Propagation Modeling And Applications In Finance, Li Zhang Dec 2016

Influence Propagation Modeling And Applications In Finance, Li Zhang

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

To appropriately use the information from social media for finance-related problems is typically challenging to both finance and data mining. Traditional schemes in finance focus on identifying the trading activities and financial events that generate asset abnormal returns, while the usage of data typically only covers regular events such as earning announcements, financial statements, and new stock issuance. Related data-driven implementations mainly focus on developing trading strategies using social media data, while the results usually lack theoretical explanations. This work is designed to fill the gap between the usage of social media data and financial theories, with comprehensive evaluations using …

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Evolution Of Immiscibly Blended Functionalized Polymers With Respect To Cure Parameters And Formulation, Nicholas Walter Heller Dec 2016

Evolution Of Immiscibly Blended Functionalized Polymers With Respect To Cure Parameters And Formulation, Nicholas Walter Heller

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Powder coatings are becoming ubiquitous in the coating marketplace due to the absence of solvents in their formulation, but they have yet to see implementation in low-reflectance outdoor applications. This demand could be met by utilizing polymer blends formulated with low loadings of matting agents and pigments. The goal of this research is a thorough characterization of prototype low-reflectance coatings through several analytical techniques. Prototypical thermoset blends consist of functionalized polyurethanes rendered immiscible by differences in polar and hydrogen bonding characteristics, resulting in a surface roughened by droplet domains. Analysis of both pigmented and control clear films was performed. This …

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Light-Induced Self-Assembly And Diffusion Of Nanoclusters, Wenxuan Lian Dec 2016

Light-Induced Self-Assembly And Diffusion Of Nanoclusters, Wenxuan Lian

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Novel methods to build multiple types of three-dimensional structures from various nanoscale components are the most exciting and challenging questions in nano-science. The properties of the assembled structures can be potentially and designed, but the development of such approaches is challenging. In order to realize such rational assembly, a tunable interaction medium is often introduced into the system. Soft matter, such as polymers, surfactants and biomolecules are used to modify the surfaces of the nanoscale building blocks. Deoxyribonucleic acid (DNA) strands are known as polynucleotides since they are composed of simpler units called nucleotides. There are unique base pairing rules …

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Applications Of Tensor Network Algorithms In Quantum Many-Body Physics, Colin Gareth West Dec 2016

Applications Of Tensor Network Algorithms In Quantum Many-Body Physics, Colin Gareth West

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The classical simulation of many-body quantum systems is an essential tool in understanding many fundamental aspects of condensed matter physics. But a major obstacle arises from the number of degrees of freedom involved in describing such systems, which is exponential in the system size. Recently, however, a class of numerical techniques based on structures called "tensor networks" has emerged, which allows many "typical" quantum states (such as the ground states of gapped, local Hamiltonians) to be represented much more efficiently. In this work we extend and apply these techniques to consider several central topics in quantum many-body physics. After reviewing …

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Physical Polymerization Mechanisms In The Chemistry-To-Biology Transition, Elizaveta Guseva Dec 2016

Physical Polymerization Mechanisms In The Chemistry-To-Biology Transition, Elizaveta Guseva

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Studying complex systems and emergent phenomena is very popular today. The reason is that we desperately need more knowledge about many complex systems such as cells, organisms, society and emergent phenomena on the internet. Applying physical and quantitative methods to such systems resulted in many discoveries, yet a lot of knowledge is missing. In particular, we don’t fully understand living systems including their emergence. What are the minimal requirements for life? How to make a chemical system capable of inheritance and open ended evolution? If a system is capable of Darwinian evolution, is it necessarily a living system? Modern life …

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Estimation Of Stable Distribution And Its Application To Credit Risk, Hua Mo Dec 2016

Estimation Of Stable Distribution And Its Application To Credit Risk, Hua Mo

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

To capture the heavy tails and the volatility clustering of asset returns is always an important topic in Â…nancial market. We studies two projects related to the Alpha Stable distribution and Classical Tempered Stable(CTS) distribution respectively which both have desired properties to accommodate heavy-tails and capture skewness in Â…nancial series. (1) In the major part of the Â…rst project, we introduce the algorithm of indirect inference method. By using the skewed-t distribution as an auxiliary model which is easier to handle, we can estimate the parameters of the Alpha Stable distribution since these two models have the same numbers of …

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Clustering And Classification Methods For Prediction Of The Risk For Developing Disease, Hyejoo Lee Dec 2016

Clustering And Classification Methods For Prediction Of The Risk For Developing Disease, Hyejoo Lee

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The purpose of this study is to develop a statistical model to predict the risk for developing disease. In order to enrich our general understanding of schizophrenia disorder, several clustering techniques are used as a preliminary study. Schizophrenia is a heterogeneous decease with great variability in symptoms, cognition, biology and course of illness. Some of this variability may be explained by latent subgroups that differ in etiology and key features. Individuals with paternal age related schizophrenia (PARS) may represent such a subgroup as evidence suggests a distinct symptom profile. Using K-means and hierarchical clustering on a large sample of schizophrenia …

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Complementarity In The Structure And Dynamics Of Protein-Dna Search And Recognition: A Multiscale Modeling Study, Kevin E. Hauser Dec 2016

Complementarity In The Structure And Dynamics Of Protein-Dna Search And Recognition: A Multiscale Modeling Study, Kevin E. Hauser

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Transcription factors (TF) interact with DNA to regulate gene expression by specifically binding one or two sequences out of millions of possible sites in a genome. Sequence specific binding (recognition) arises from two mechanisms: amino acid-nucleobase H-bonding (direct readout), and sequence-dependent DNA deformability and structure (indirect readout). These lead to tight, specific binding. TFs can also rapidly search for their target by attaching to any sequence and then sliding along DNA. This decreases the space through which a TF randomly walks to stumble on the target. Tight binding and rapid sliding are optimized because TFs can switch between different DNA-binding …

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Mechanistic Studies In Heterogeneous Catalysis Via In Situ Ft-Ir Spectroscopy, Joseph William Magee Dec 2016

Mechanistic Studies In Heterogeneous Catalysis Via In Situ Ft-Ir Spectroscopy, Joseph William Magee

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

Dependence on a finite supply of fossil fuel-based energy sources has provided motivation for research in and development of alternative, renewable energy sources. A strong candidate as an alternative fuel is ethanol. Ethanol has a high energy density, low toxicity, and as a liquid, compatibility with the existing fuel delivery infrastructure. When considering the possibility of using ethanol as a fuel, both synthetic methods to produce ethanol and reactions that convert ethanol to energy should be optimized. One method to produce ethanol is through the conversion of synthesis gas, or syngas, (CO + H2). Currently, syngas conversion is used to …

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Overcoming Element Quality Dependence Of Finite Element Methods, Rebecca Conley Dec 2016

Overcoming Element Quality Dependence Of Finite Element Methods, Rebecca Conley

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The finite element methods (FEM) are important techniques in engineering for solving partial differential equations, especially on complex geometries. One limitation of the classical FEM is its heavy dependence on element shape quality for stability and good performance. We introduce the Adaptive Extended Stencil Finite Element Method (AES-FEM) as a means to overcome this dependence on element shape quality. Our method replaces the traditional basis functions with a set of generalized Lagrange polynomial (GLP) basis functions, which we construct using local weighted least-squares approximations. The method preserves the theoretical framework of FEM, and allows imposing essential boundary conditions and integrating …

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Estimation And Detection Of Network Variation In Intraday Stock Market, Shanshan Li Dec 2016

Estimation And Detection Of Network Variation In Intraday Stock Market, Shanshan Li

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

The last few years have witnessed an exponential growth in the collection and analysis of financial market data. Investigating the interactions between the dynamics of the financial system and extracting useful information from these multivariate data streams can help us in improving our understanding of the underlying backbone in the financial market. These massive noisy data sets require the application of suitable and efficient dependency measurements for their analysis in a real-time environment. And that is why network analysis has emerged recently, which is a plausible representation helps interpret the hidden interconnection between the elements in large datasets. However, most …

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