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Radial Singular Solutions To Semilinear Partial Differential Equations, Marcelo A. Almora RIos 2021 Claremont Colleges 81818app手机版下载

Radial Singular Solutions To Semilinear Partial Differential Equations, Marcelo A. Almora Rios

HMC Senior Theses

We show the existence of countably many non-degenerate continua of singular radial solutions to a p-subcritical, p-Laplacian Dirichlet problem on the unit ball in R^N. This result generalizes those for the 2-Laplacian to any value p and extends recent work on the p-Laplacian by considering solutions both radial and singular.


Geometric Unified Method In 3d Object Classification, Mengyi Shan 2021 Claremont Colleges

Geometric Unified Method In 3d Object Classification, Mengyi Shan

HMC Senior Theses

3D object classification is one of the most popular topics in the field of computer vision and computational geometry. Currently, the most popular state-of-the-art algorithm is the so-called Convolutional Neural Network (CNN) models with various representations that capture different features of the given 3D data, including voxels, local features, multi-view 2D features, and so on. With CNN as a holistic approach, researches focus on improving the accuracy and efficiency by designing the neural network architecture. This thesis aims to examine the existing work on 3D object classification and explore the underlying theory by integrating geometric approaches. By using geometric algorithms ...


Search For Gravitational Waves From Scorpius X-1 In The Second Advanced Ligo Observing Run With An Improved Hidden Markov Model, Tiffany Summerscales, LIGO Scientific Collaboration and the Virgo Collaboration 2020 Andrews University 81818app手机版下载

Search For Gravitational Waves From Scorpius X-1 In The Second Advanced Ligo Observing Run With An Improved Hidden Markov Model, Tiffany Summerscales, Ligo Scientific Collaboration And The Virgo Collaboration

Faculty Publications

We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO’s second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h95%0 ...


An Enticing Study Of Prime Numbers Of The Shape 𝑝 = 𝑥^2 + 𝑦^2, Xiaona Zhou 2020 CUNY New York City College of Technology

An Enticing Study Of Prime Numbers Of The Shape 𝑝 = 𝑥^2 + 𝑦^2, Xiaona Zhou

Publications and Research

We will study and prove important results on primes of the shape 𝑥2 + 𝑦281818app手机版下载 using number theoretic techniques. Our analysis involves maps, actions over sets, fixed points and involutions. This presentation is readily accessible to an advanced undergraduate student and lay the groundwork for future studies.


A Near-Optimal Change-Detection Based Algorithm For Piecewise-Stationary Combinatorial Semi-Bandits, Huozhi ZHOU, Lingda WANG, Lav N. VARSHNEY, Ee Peng LIM 2020 Singapore Management University

A Near-Optimal Change-Detection Based Algorithm For Piecewise-Stationary Combinatorial Semi-Bandits, Huozhi Zhou, Lingda Wang, Lav N. Varshney, Ee Peng Lim

Research Collection School Of Information Systems

81818app手机版下载We investigate the piecewise-stationary combinatorial semi-bandit problem. Compared to the original combinatorial semi-bandit problem, our setting assumes the reward distributions of base arms may change in a piecewise-stationary manner at unknown time steps. We propose an algorithm, GLR-CUCB, which incorporates an efficient combinatorial semi-bandit algorithm, CUCB, with an almost parameter-free change-point detector, the Generalized Likelihood Ratio Test (GLRT). Our analysis shows that the regret of GLR-CUCB is upper bounded by O(√NKT logT), where N is the number of piecewise-stationary segments, K is the number of base arms, and T is the number of time steps. As a complement, we ...


Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, Shane Ylagan 2020 University of Arkansas, Fayetteville

Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, Shane Ylagan

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

81818app手机版下载The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4·6H2O) is an understudied material that can be created from Pcontaining wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple super phosphate (TSP) on corn (Zea mays) and soybean (Glycine max) response in a 79-day greenhouse ...


Teaching Applications And Implications Of Blockchain Via Project-Based Learning: A Case Study, Kevin Mentzer, Mark Frydenberg, David J. Yates 2020 Bryant University

Teaching Applications And Implications Of Blockchain Via Project-Based Learning: A Case Study, Kevin Mentzer, Mark Frydenberg, David J. Yates

Computer Information Systems Journal Articles

81818app手机版下载This paper presents student projects analyzing or using blockchain technologies, created by students enrolled in courses dedicated to teaching blockchain, at two different universities during the 2018-2019 academic year. Students explored perceptions related to storing private healthcare information on a blockchain, managing the security of Internet of Things devices, maintaining public governmental records, and creating smart contracts. The course designs, which were centered around project-based learning, include self-regulated learning and peer feedback as ways to improve student learning. Students either wrote a research paper or worked in teams on a programming project to build and deploy a blockchain-based application using ...


Detecting Hacker Threats: Performance Of Word And Sentence Embedding Models In Identifying Hacker Communications, Susan McKeever, Brian Keegan, Andrei Quieroz 2020 Technological University Dublin

Detecting Hacker Threats: Performance Of Word And Sentence Embedding Models In Identifying Hacker Communications, Susan Mckeever, Brian Keegan, Andrei Quieroz

Conference papers

81818app手机版下载Abstract—Cyber security is striving to find new forms of protection against hacker attacks. An emerging approach nowadays is the investigation of security-related messages exchanged on deep/dark web and even surface web channels. This approach can be supported by the use of supervised machine learning models and text mining techniques. In our work, we compare a variety of machine learning algorithms, text representations and dimension reduction approaches for the detection accuracies of software-vulnerability-related communications. Given the imbalanced nature of the three public datasets used, we investigate appropriate sampling approaches to boost detection accuracies of our models. In addition, we ...


Approximating Special Social Influence Maximization Problems, Jie Wu, Ning Wang 2020 Rowan University

Approximating Special Social Influence Maximization Problems, Jie Wu, Ning Wang

Faculty Scholarship for the College of Science & Mathematics

Social Influence Maximization Problems (SIMPs) deal with selecting k seeds in a given Online Social Network (OSN) to maximize the number of eventually-influenced users. This is done by using these seeds based on a given set of influence probabilities among neighbors in the OSN. Although the SIMP has been proved to be NP-hard, it has both submodular (with a natural diminishing-return) and monotone (with an increasing influenced users through propagation) that make the problem suitable for approximation solutions. However, several special SIMPs cannot be modeled as submodular or monotone functions. In this paper, we look at several conditions under which ...


Deep Neural Network For Complex Open-Water Wetland Mapping Using High-Resolution Worldview-3 And Airborne Lidar Data, Vitor S. Martins, Amy L. Kaleita, Brian K. Gelder, Gustavo W. Nagel, Daniel A. Maciel 2020 Iowa State University 81818app手机版下载

Deep Neural Network For Complex Open-Water Wetland Mapping Using High-Resolution Worldview-3 And Airborne Lidar Data, Vitor S. Martins, Amy L. Kaleita, Brian K. Gelder, Gustavo W. Nagel, Daniel A. Maciel

Agricultural and Biosystems Engineering Publications

81818app手机版下载Wetland inventory maps are essential information for the conservation and management of natural wetland areas. The classification framework is crucial for successful mapping of complex wetlands, including the model selection, input variables and training procedures. In this context, deep neural network (DNN) is a powerful technique for remote sensing image classification, but this model application for wetland mapping has not been discussed in the previous literature, especially using commercial WorldView-3 data. This study developed a new framework for wetland mapping using DNN algorithm and WorldView-3 image in the Millrace Flats Wildlife Management Area, Iowa, USA. The study area has several ...


Water, Fish, And Fire: Interdisciplinary Research On Ecosystem Services And Climate Adaptation, Liana Prudencio 2020 Utah State University

Water, Fish, And Fire: Interdisciplinary Research On Ecosystem Services And Climate Adaptation, Liana Prudencio

All Graduate Theses and Dissertations

Ecosystem services, or benefits from the environment, are plentiful and vary from place to place. Human activities and climate change have impacted these services in every region of the world. This dissertation explores multiple ecosystem services, from water quality improvement to provisioning of fish and habitat, in multiple and international contexts. The first chapter synthesizes the literature on stormwater management and ecosystem services, finding that research at this intersection has provided many parcel-level studies and frameworks for implementing green infrastructure. The second chapter extends the stormwater management literature by quantifying the impacts of green infrastructure on water quantity and quality ...


Sum Of Cubes Of The First N Integers, Obiamaka L. Agu 2020 California State University, San Bernardino

Sum Of Cubes Of The First N Integers, Obiamaka L. Agu

Electronic Theses, Projects, and Dissertations

In Calculus we learned that 􏰅Sum^{n}_{k=1} k = [n(n+1)]/2 , that Sum^{􏰅n}_{k=1} k^2 = [n(n+1)(2n+1)]/6 , and that Sum^{n}_{k=1} k^{3} = (n(n+1)/2)^{2}. These formulas are useful when solving for the area below quadratic or cubic function over an interval [a, b]. This tedious process, solving for areas under a quadratic or a cubic, served as motivation for the introduction of Riemman integrals. For the overzealous math student, these steps were replaced by a simpler method of evaluating antiderivatives at ...


Embedded-Atom-Method Modeling Of Alkali-Metal/Transition-Metal Interfaces, Jake D. Christensen 2020 Utah State University 81818app手机版下载

Embedded-Atom-Method Modeling Of Alkali-Metal/Transition-Metal Interfaces, Jake D. Christensen

All Graduate Theses and Dissertations

81818app手机版下载Understanding the thermal properties of materials is essential to using those materials for technological advancement which can benefit civilization. For example, it has been proposed that essential components of tokamaks, devices which perform fusion, be made out of tungsten with a thin layer of lithium on the surface. To that end, this thesis seeks to calculate the thermal properties of a layer of alkali atoms, like lithium and sodium, on tungsten and molybdenum substrates. We use an Embedded Atom Method (EAM) model to perform our calculations. This type of model has been widely used to describe the interaction between atoms ...


Delta Hedging Of Financial Options Using Reinforcement Learning And An Impossibility Hypothesis, Ronak Tali 2020 Utah State University 81818app手机版下载

Delta Hedging Of Financial Options Using Reinforcement Learning And An Impossibility Hypothesis, Ronak Tali

All Graduate Theses and Dissertations

81818app手机版下载In this thesis we take a fresh perspective on delta hedging of financial options as undertaken by market makers. The current industry standard of delta hedging relies on the famous Black Scholes formulation that prescribes continuous time hedging in a way that allows the market maker to remain risk neutral at all times. But the Black Scholes formulation is a deterministic model that comes with several strict assumptions such as zero transaction costs, log normal distribution of the underlying stock prices, etc. In this paper we employ Reinforcement Learning to redesign the delta hedging problem in way that allows us ...


Classification Of Jacobian Elliptic Fibrations On A Special Family Of K3 Surfaces Of Picard Rank Sixteen, Thomas Hill 2020 Utah State University 81818app手机版下载

Classification Of Jacobian Elliptic Fibrations On A Special Family Of K3 Surfaces Of Picard Rank Sixteen, Thomas Hill

All Graduate Theses and Dissertations

K3 surfaces are an important tool used to understand the symmetries in physics that link different string theories, called string dualities. For example, heterotic string theory compactified on an elliptic curve describes a theory physically equivalent to (dual to) F-theory compactified on a K3 surface. In fact, M-theory, the type IIA string, the type IIB string, the Spin(32)/Z2 heterotic string, and the E8 x E8 81818app手机版下载heterotic string are all related by compactification on Calabi-Yau manifolds.

81818app手机版下载We study a special family of K3 surfaces, namely a family of rank sixteen K3 surfaces polarized by the lattice ...


The Development And Use Of A Secondary Electron Yield Database For Spacecraft Charge Modeling, Phillip Lundgreen 2020 Utah State University

The Development And Use Of A Secondary Electron Yield Database For Spacecraft Charge Modeling, Phillip Lundgreen

All Graduate Theses and Dissertations

Charge modeling of electron-solid interactions requires a detailed and accurate compilation of experimental data on which to base its physics and against which to test its predictions. Historically researchers used methods involving individual research or information taken from existing, vague, databases that were often found wanting. To streamline the charge modeling process, a collection of data has been assembled and categorized based upon surface morphology and contamination from various published sources and existing databases. The quality and quantity of the compilation vary widely with very little information offered with regards to surface conditions of various materials (contamination, morphology, etc. ...). Included ...


Finite-Strain Scale-Free Phase-Field Approach To Multivariant Martensitic Phase Transformations With Stress-Dependent Effective Thresholds, Hamed Babaei, Valery I. Levitas 2020 Iowa State University 81818app手机版下载

Finite-Strain Scale-Free Phase-Field Approach To Multivariant Martensitic Phase Transformations With Stress-Dependent Effective Thresholds, Hamed Babaei, Valery I. Levitas

Aerospace Engineering Publications

81818app手机版下载A scale-free phase-field model for martensitic phase transformations (PTs) at finite strains is developed as an essential generalization of small-strain models in Levitas et al. (2004) and Idesman et al. (2005). The theory includes finite elastic and transformational strains and rotations as well as anisotropic and different elastic properties of phases. The gradient energy term is excluded, and the model is applicable for any scale greater than 100 nm. The model tracks finite-width interfaces between austenite and the mixture of martensitic variants only; volume fractions of martensitic variants are the internal variables rather than order parameters. The concept of the ...


Sea Surface Temperature Across The Subarctic North Pacific And Marginal Seas Through The Past 20,000 Years: A Paleoceanographic Synthesis, Catherine V. Davis, Sarah E. Myhre, Curtis Deutsch, Beth Caissie, Summer Praetorius, Marisa Borreggine, Robert Thunell 2020 University of South Carolina

Sea Surface Temperature Across The Subarctic North Pacific And Marginal Seas Through The Past 20,000 Years: A Paleoceanographic Synthesis, Catherine V. Davis, Sarah E. Myhre, Curtis Deutsch, Beth Caissie, Summer Praetorius, Marisa Borreggine, Robert Thunell

Geological and Atmospheric Sciences Publications

81818app手机版下载Deglacial sea surface conditions in the subarctic North Pacific and marginal seas are the subject of increasing interest in paleoceanography. However, a cohesive picture of near-surface oceanography from which to compare inter and intra-regional variability through the last deglaciation is lacking. We present a synthesis of sea surface temperature covering the open North Pacific and its marginal seas, spanning the past 20 ka using proxy records from foraminiferal calcite (δ18O and Mg/Ca) and coccolithophore alkenones (Uk’37). Sea surface temperature proxies tend to be in agreement through the Holocene, though Uk’37 records are often interpreted as warmer than ...


Effects Of Seawater Exchange On Water Chemistry Among Coastal Lakes With Intermittent Connections To The Sea, A. Challen Hyman, Dana Bigham Stephens 2020 Virginia Institute of Marine Science

Effects Of Seawater Exchange On Water Chemistry Among Coastal Lakes With Intermittent Connections To The Sea, A. Challen Hyman, Dana Bigham Stephens

VIMS Articles

81818app手机版下载Intermittently closed and open lakes and lagoons (ICOLLs) are a dynamic class of coastal waterbodies with the unique feature of intermittently connecting to the sea. Understanding the functioning and potential threats of these globally rare systems is important to their preservation and protection. Coastal dune lakes of northwest Florida are one example of an understudied group of ICOLLs which connect with the Gulf of Mexico for brief periods of time. Using a 17-year, monthly water chemistry dataset, we analyzed long-term patterns in water chemistry among 16 coastal dune lakes. Using salinity as a proxy for frequency of seawater inflows, principal ...


Modification Of Chm20 Lab: Synthesis Of Aspirin, Nicole Diaz, Amy Musselman Prof. 2020 Kutztown University of Pennsylvania 81818app手机版下载

Modification Of Chm20 Lab: Synthesis Of Aspirin, Nicole Diaz, Amy Musselman Prof.

KU Inspires! Undergraduate Research Day

No abstract provided.