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2020

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Full-Text Articles in Physical Sciences and Mathematics

Monarch Science Observer, Volume 7, College Of Sciences, Old Dominion University Dec 2020

Monarch Science Observer, Volume 7, College Of Sciences, Old Dominion University

College of Sciences Newsletter

December-Fall 2020 issue of Monarch Science Observer, ODU College of Sciences Newsletter.


Causal Intervention For Weakly-Supervised Semantic Segmentation, Zhang Dong, Hanwang Zhang, Jinhui Tang, Xian-Sheng Hua, Qianru Sun Dec 2020

Causal Intervention For Weakly-Supervised Semantic Segmentation, Zhang Dong, Hanwang Zhang, Jinhui Tang, Xian-Sheng Hua, Qianru Sun

Research Collection School Of Computing and Information Systems

We present a causal inference framework to improve Weakly-Supervised Semantic Segmentation (WSSS). Specifically, we aim to generate better pixel-level pseudo-masks by using only image-level labels --- the most crucial step in WSSS. We attribute the cause of the ambiguous boundaries of pseudo-masks to the confounding context, e.g., the correct image-level classification of "horse'' and "person'' may be not only due to the recognition of each instance, but also their co-occurrence context, making the model inspection (e.g., CAM) hard to distinguish between the boundaries. Inspired by this, we propose a structural causal model to analyze the causalities among images, contexts, and …


A Bert-Based Dual Embedding Model For Chinese Idiom Prediction, Minghuan Tan, Jing Jiang Dec 2020

A Bert-Based Dual Embedding Model For Chinese Idiom Prediction, Minghuan Tan, Jing Jiang

Research Collection School Of Computing and Information Systems

Chinese idioms are special fixed phrases usually derived from ancient stories, whose meanings are oftentimes highly idiomatic and non-compositional. The Chinese idiom prediction task is to select the correct idiom from a set of candidate idioms given a context with a blank. We propose a BERT-based dual embedding model to encode the contextual words as well as to learn dual embeddings of the idioms. Specifically, we first match the embedding of each candidate idiom with the hidden representation corresponding to the blank in the context. We then match the embedding of each candidate idiom with the hidden representations of all …


Optimal Collaborative Path Planning For Unmanned Surface Vehicles Carried By A Parent Boat Along A Planned Route, Ari Carisza Graha Prasetia, I-Lin Wang, Aldy Gunawan Dec 2020

Optimal Collaborative Path Planning For Unmanned Surface Vehicles Carried By A Parent Boat Along A Planned Route, Ari Carisza Graha Prasetia, I-Lin Wang, Aldy Gunawan

Research Collection School Of Computing and Information Systems

In this paper, an effective mechanism using a fleet of unmanned surface vehicles (USVs) carried by a parent boat (PB) is proposed to complete search or scientific tasks over multiple target water areas within a shorter time . Specifically, multiple USVs can be launched from the PB to conduct such operations simultaneously, and each USV can return to the PB for battery recharging or swapping and data collection in order to continue missions in a more extended range. The PB itself follows a planned route with a flexible schedule taking into consideration locational constraints or collision avoidance in a real-world …


A Near-Optimal Change-Detection Based Algorithm For Piecewise-Stationary Combinatorial Semi-Bandits, Huozhi Zhou, Lingda Wang, Lav N. Varshney, Ee-Peng Lim Dec 2020

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 Computing and Information Systems

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 also …


Acquisition, Processing, And Analysis Of Video, Audio And Meteorological Data In Multi-Sensor Electronic Beehive Monitoring, Sarbajit Mukherjee Dec 2020

Acquisition, Processing, And Analysis Of Video, Audio And Meteorological Data In Multi-Sensor Electronic Beehive Monitoring, Sarbajit Mukherjee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, a widespread decline has been seen in honey bee population and this is widely attributed to colony collapse disorder. Hence, it is of utmost importance that a system is designed to gather relevant information. This will allow for a deeper understanding of the possible reasons behind the above phenomenon to aid in the design of suitable countermeasures.

Electronic Beehive Monitoring is one such way of gathering critical information regarding a colony’s health and behavior without invasive beehive inspections. In this dissertation, we have presented an electronic beehive monitoring system called BeePi that can be placed on top …


Benchmarks And Controls For Optimization With Quantum Annealing, Erica Kelley Grant Dec 2020

Benchmarks And Controls For Optimization With Quantum Annealing, Erica Kelley Grant

Doctoral Dissertations

Quantum annealing (QA) is a metaheuristic specialized for solving optimization problems which uses principles of adiabatic quantum computing, namely the adiabatic theorem. Some devices implement QA using quantum mechanical phenomena. These QA devices do not perfectly adhere to the adiabatic theorem because they are subject to thermal and magnetic noise. Thus, QA devices return statistical solutions with some probability of success where this probability is affected by the level of noise of the system. As these devices improve, it is believed that they will become less noisy and more accurate. However, some tuning strategies may further improve that probability of …


Exploration Of Mid To Late Paleozoic Tectonics Along The Cincinnati Arch Using Gis And Python To Automate Geologic Data Extraction From Disparate Sources, Kenneth Steven Boling Dec 2020

Exploration Of Mid To Late Paleozoic Tectonics Along The Cincinnati Arch Using Gis And Python To Automate Geologic Data Extraction From Disparate Sources, Kenneth Steven Boling

Doctoral Dissertations

Structure contour maps are one of the most common methods of visualizing geologic horizons as three-dimensional surfaces. In addition to their practical applications in the oil and gas and mining industries, these maps can be used to evaluate the relationships of different geologic units in order to unravel the tectonic history of an area. The construction of high-resolution regional structure contour maps of a particular geologic horizon requires a significant volume of data that must be compiled from all available surface and subsurface sources. Processing these data using conventional methods and even basic GIS tools can be tedious and very …


Developing Highly Reversible Li Metal Anode With Mossy/Dendritic Li Suppression In High Energy Density Batteries, Xi Chen Dec 2020

Developing Highly Reversible Li Metal Anode With Mossy/Dendritic Li Suppression In High Energy Density Batteries, Xi Chen

Theses and Dissertations

Lithium-ion battery technology has wide impact on our daily life. However, most of the commercial batteries with limited energy density are unable to meet the growing demand of electrical vehicles, portable electronic devices and other energy storage systems. Therefore, the development of new electrode materials with high energy density and reliable performance has become a critical mission for researchers. Particularly replacing graphite anode with Li metal is one of most viable approaches to break the limitation of energy density in batteries. Metallic lithium is one of the most promising anode materials, which has a high theoretical specific capacity of 3860 …


The Surface Diffusion And The Willmore Flow For Uniformly Regular Hypersurfaces, Jeremy Lecrone, Yuanzhen Shao, Gieri Simonett Dec 2020

The Surface Diffusion And The Willmore Flow For Uniformly Regular Hypersurfaces, Jeremy Lecrone, Yuanzhen Shao, Gieri Simonett

Department of Math & Statistics Faculty Publications

We consider the surface diffusion and Willmore flows acting on a general class of (possibly non–compact) hypersurfaces parameterized over a uniformly regular reference manifold possessing a tubular neighborhood with uniform radius. The surface diffusion and Willmore flows each give rise to a fourth–order quasilinear parabolic equation with nonlinear terms satisfying a specific singular structure. We establish well–posedness of both flows for initial surfaces that are C1+α–regular and parameterized over a uniformly regular hypersurface. For the Willmore flow, we also show long–term existence for initial surfaces which are C1+α–close to a sphere, and we prove …


Vibration Overtone Hyperpolarizability Measured For H2 Using Electric Field Induced Second Harmonic Generation, Rachel Ellis Dec 2020

Vibration Overtone Hyperpolarizability Measured For H2 Using Electric Field Induced Second Harmonic Generation, Rachel Ellis

UNLV Theses, Dissertations, Professional Papers, and Capstones

The vibrational contribution to the second hyperpolarizability (γ) of gas phase H2 was measured using electric field induced second harmonic generation. Measurements were made for the pure vibrational 3-0 Q(J) overtone transitions (v=0,J → v’=3,J for J = 0,1,2,3). Measured intensities were found to be 4-14% larger than ab initio calculations. The first chapter of this thesis provides an introduction to nonlinear optics, second harmonic generation, and the tensor nature of hyperpolarizabilities. The second chapter provides theoretical expressions for γ and relevant static and Raman polarizabilities. The third chapter covers the experimental design and electric field induced second harmonic generation. …


Diagonalization Of 1-D Schrodinger Operators With Piecewise Constant Potentials, Sarah Wright Dec 2020

Diagonalization Of 1-D Schrodinger Operators With Piecewise Constant Potentials, Sarah Wright

Master's Theses

In today's world our lives are very layered. My research is meant to adapt current inefficient numerical methods to more accurately model the complex situations we encounter. This project focuses on a specific equation that is used to model sound speed in the ocean. As depth increases, the sound speed changes. This means the variable related to the sound speed is not constant. We will modify this variable so that it is piecewise constant. The specific operator in this equation also makes current time-stepping methods not practical. The method used here will apply an eigenfunction expansion technique used in previous …


Lightweight Deep Learning For Botnet Ddos Detection On Iot Access Networks, Eric A. Mccullough Dec 2020

Lightweight Deep Learning For Botnet Ddos Detection On Iot Access Networks, Eric A. Mccullough

MSU Graduate Theses

With the proliferation of the Internet of Things (IoT), computer networks have rapidly expanded in size. While Internet of Things Devices (IoTDs) benefit many aspects of life, these devices also introduce security risks in the form of vulnerabilities which give hackers billions of promising new targets. For example, botnets have exploited the security flaws common with IoTDs to gain unauthorized control of hundreds of thousands of hosts, which they then utilize to carry out massively disruptive distributed denial of service (DDoS) attacks. Traditional DDoS defense mechanisms rely on detecting attacks at their target and deploying mitigation strategies toward the attacker …


Enhancement Of Critical Current In High-Temperature Superconductors By Ion Beam Irradiation Induced Defects, Prashanta Mani Niraula Dec 2020

Enhancement Of Critical Current In High-Temperature Superconductors By Ion Beam Irradiation Induced Defects, Prashanta Mani Niraula

Dissertations

Particle irradiation is used to induce defects in high-temperature superconducting Y1Ba2Cu3O7-x (YBCO) coated conductors, containing predominantly c-axis oriented barium zirconate (BZO) nanorods as pre-existing vortex pinning defects. Samples are irradiated with 50.0 MeV Cu ions with doses of 2.5 x 1012, 2.0 x 1012, 1.5 x 1012, 1.0 x 1012, 0.75 x 1012, 0.5 x 1012, 0.05 x 1012 ions/cm2. The dose of 0.5 x 1012 ions/cm2 is found to be the optimal dose with a …


Recompilation Of Lithological Proxies Across The Permian-Triassic Boundary, Heather Nicole Brauer Dec 2020

Recompilation Of Lithological Proxies Across The Permian-Triassic Boundary, Heather Nicole Brauer

Earth & Environmental Sciences Theses

The largest mass extinction occurred near the Permian-Triassic boundary (PTB; 251.902 ± 0.024 Ma; Shen et al., 2011), with the demise of more than 90% of marine species and 70% of terrestrial species. This study expands sedimentary data bases created by Rees and others (2002) and the PALEOMAP Project by Scotese (2001). Lithological data was categorized as upper Permian (259.1-254.902 Ma) or Lower Triassic (251.902-247.2 Ma), and the paleogeographic information of the proxies were reconstructed using GPlates 2.0. These lithological proxies are compared with climate sensitivity simulations from the fully coupled comprehensive Community Climate System Model (CCSM3). The climate simulation …


Generalized Algorithmic Frameworks For Optimizing Distance Calls In Generalized Metric Space Proximity Problems And Methods For Realizing Efficient Signal Reconstruction, Jees Augustine Dec 2020

Generalized Algorithmic Frameworks For Optimizing Distance Calls In Generalized Metric Space Proximity Problems And Methods For Realizing Efficient Signal Reconstruction, Jees Augustine

Computer Science and Engineering Dissertations

The exponential rise in data, along with its heterogeneity and complexity, helped individuals, businesses, hospitals, enterprises and even governments to thrive on data-driven decision making. However, as the size and complexity of the data surged, challenges in searching for similar objects within databases (proximity search) compounded. As is well known, proximity search is the key and successful method used in Information Retrieval (IR) in vast databases including, Genomics Databases, Image Databases, Video Databases, Text databases, etc. The objective is to retrieve contents from the database, similar to a given object in the database. This dissertation revisits a suite of popular …


Deep Learning-Based, Passive Fault Tolerant Control Facilitated By A Taxonomy Of Cyber-Attack Effects, Dean C. Wardell Dec 2020

Deep Learning-Based, Passive Fault Tolerant Control Facilitated By A Taxonomy Of Cyber-Attack Effects, Dean C. Wardell

Theses and Dissertations

In the interest of improving the resilience of cyber-physical control systems to better operate in the presence of various cyber-attacks and/or faults, this dissertation presents a novel controller design based on deep-learning networks. This research lays out a controller design that does not rely on fault or cyber-attack detection. Being passive, the controller’s routine operating process is to take in data from the various components of the physical system, holistically assess the state of the physical system using deep-learning networks and decide the subsequent round of commands from the controller. This use of deep-learning methods in passive fault tolerant control …


Electrochemical And Photoelectrochemical Properties Of Oxide And Chalcogenide Semiconductors, Farinaz Firouzan Dec 2020

Electrochemical And Photoelectrochemical Properties Of Oxide And Chalcogenide Semiconductors, Farinaz Firouzan

Chemistry & Biochemistry Dissertations

Photoelectrochemical (PEC) water splitting via inorganic semiconductors has shown interest in technical applications such as harvesting sunlight as sustainable fuels. Chalcogen-based (S, Se, Te) semiconductors are important in numerous technology applications especially related to photovoltaic solar conversion, fuel cells, hydrogen generation etc. On the other hand, oxide semiconductors are great candidates due to their unique properties namely electrolyte stability, a wide range of bandgaps and easy access. In this vein, we investigated the quaternary metal chalcogenide, Ca(La1−xCex)2S4 (0 ≤ x ≤ 1) photoelectrochemical behavior in an aqueous redox electrolyte. These solid solution series were synthesized in Prof. Macaluso’s laboratory by …


A Set Theory Based Similarity Measure For Text Clustering And Classification, Ali A. Amer, Hassan I. Abdalla Dec 2020

A Set Theory Based Similarity Measure For Text Clustering And Classification, Ali A. Amer, Hassan I. Abdalla

All Works

© 2020, The Author(s). Similarity measures have long been utilized in information retrieval and machine learning domains for multi-purposes including text retrieval, text clustering, text summarization, plagiarism detection, and several other text-processing applications. However, the problem with these measures is that, until recently, there has never been one single measure recorded to be highly effective and efficient at the same time. Thus, the quest for an efficient and effective similarity measure is still an open-ended challenge. This study, in consequence, introduces a new highly-effective and time-efficient similarity measure for text clustering and classification. Furthermore, the study aims to provide a …


Improving Binary Classification Using Filtering Based On K-Nn Proximity Graphs, Maher Ala’Raj, Munir Majdalawieh, Maysam F. Abbod Dec 2020

Improving Binary Classification Using Filtering Based On K-Nn Proximity Graphs, Maher Ala’Raj, Munir Majdalawieh, Maysam F. Abbod

All Works

© 2020, The Author(s). One of the ways of increasing recognition ability in classification problem is removing outlier entries as well as redundant and unnecessary features from training set. Filtering and feature selection can have large impact on classifier accuracy and area under the curve (AUC), as noisy data can confuse classifier and lead it to catch wrong patterns in training data. The common approach in data filtering is using proximity graphs. However, the problem of the optimal filtering parameters selection is still insufficiently researched. In this paper filtering procedure based on k-nearest neighbours proximity graph was used. Filtering parameters …


2020 December - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University Dec 2020

2020 December - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Report

No abstract provided.


The Application And Development Of Metabolomics Methodologies For The Profiling Of Food And Cellular Toxicity, Jade Woods Dec 2020

The Application And Development Of Metabolomics Methodologies For The Profiling Of Food And Cellular Toxicity, Jade Woods

Department of Chemistry: Dissertations, Theses, and Student Research

Metabolomics is a rapidly growing field of study. Its growth reflects advancements in technology and an improved understanding of the impact of the environment on metabolism. As a result, metabolomics is now commonly employed to investigate and characterize human and plant metabolism. The first chapter of this thesis provides an introduction to metabolomics and an overview of the protocols for sample preparation, data collection and statistical analysis. The second thesis chapter describes in explicit detail the step-by-step process of extracting and analyzing metabolites collected from mammalian cells, specifically brain tissue with a focus on Parkinson’s disease. The chapter highlights important …


Packet Delivery: An Investigation Of Educational Video Games For Computer Science Education, Robert Lafferty Dec 2020

Packet Delivery: An Investigation Of Educational Video Games For Computer Science Education, Robert Lafferty

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

The field of educational video games has rapidly grown since the 1970s, mostly producing video games to teach core education concepts such as mathematics, natural science, and English. Recently, various research groups have developed educational games to address elective topics such as finance and health. Educational video games often target grade school audiences and rarely target high school students, college students, or adults. Computer science topics are not a common theme among educational video games; the games that address Computer Science topics teach computer fundamentals, such as typing or basic programming, to young audiences.

Packet Delivery, an educational video …


Hyperpolarized Carbon-13 Magnetic Resonance Measurements Of Tissue Perfusion And Metabolism, Keith Michel Dec 2020

Hyperpolarized Carbon-13 Magnetic Resonance Measurements Of Tissue Perfusion And Metabolism, Keith Michel

Dissertations & Theses (Open Access)

Hyperpolarized Magnetic Resonance Imaging (HP MRI) is an emerging modality that enables non-invasive interrogation of cells and tissues with unprecedented biochemical detail. This technology provides rapid imaging measurements of the activity of a small quantity of molecules with a strongly polarized nuclear magnetic moment. This polarization is created in a polarizer separate from the imaging magnet, and decays continuously towards a non-detectable thermal equilibrium once the imaging agent is removed from the polarizer and administered by intravenous injection. Specialized imaging strategies are therefore needed to extract as much information as possible from the HP signal during its limited lifetime.

In …


A Divide And Conquer With Semi-Global Failover For Software Defined Networks, Kasra Goravanchi Dec 2020

A Divide And Conquer With Semi-Global Failover For Software Defined Networks, Kasra Goravanchi

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nowadays, many service providers need to provide many other functions than just a network connectivity. They also need to provide network functions such as network address translation, firewall, encryption, Domain Name Service (DNS), caching, routing and many other services. Usually these functions come with the hardware at the user or customer’s premises. This can increase the revenue of the revenue, but also can cost a lot and also be extremely difficult to maintain. Moreover, it is important to be able to configure the network and later modify the configuration to create fault tolerance and to prepare the system for future …


Constraining Viscous Protoplanetary Disk Models Using Alma Kinematic Observations, Ian Rabago Dec 2020

Constraining Viscous Protoplanetary Disk Models Using Alma Kinematic Observations, Ian Rabago

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent molecular line observations by ALMA have revealed the 3D velocity structure of protoplanetary disks, providing new insight on the mechanisms of disk accretion and ring/gap formation. Although the constant α viscous disk model has been widely used to describe the disk surface density evolution, it may not adequately describe the gas velocity at different disk heights. By carrying out viscous hydrodynamic simulations, we confirm that the vertical velocity structure varies considerably between these models. On the other hand, the surface density evolution of the disk is only dependent on the vertically integrated stress, and does not depend on a …


An Exploration Of The Numeracy Skills Required For Safe, Quality Nursing Practice, Anna Wendel Dec 2020

An Exploration Of The Numeracy Skills Required For Safe, Quality Nursing Practice, Anna Wendel

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to explore the numeracy skills required for safe, quality nursing practice. Using a descriptive mixed methods design, this study answered two research questions: 1) What numeracy skills do nurses perceive as important for providing safe, quality nursing care in the first three years of practice? 2) How do nurses incorporate numeracy skills into daily patient care during the first three years of practice? Early career nurses from a not-for-profit health care organization in the mid-Atlantic region of the United States (n=109) responded to an online survey tool developed by the student investigator that ranked …


Equivalences Of Determinacy Between Levels Of The Borel Hierarchy And Long Games, And Some Generalizations, Katherine Aimee Yost Dec 2020

Equivalences Of Determinacy Between Levels Of The Borel Hierarchy And Long Games, And Some Generalizations, Katherine Aimee Yost

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis will be primarily focused on directly proving that the determinacy of Borel games in X^ω is equivalent to the determinacy of certain long open games, from a fragment of ZFC that’s well-known to be insufficient to prove Borel determinacy. The main theorem is a level by level result which shows the equivalence between determinacy of open games in a long tree, [Υ^α], and determinacy of Σ_0^α games in X^ω. In Chapter 9, we mimic the proof used in our main theorem to show that the determinacy of clopen games in the product space X^ω × ω^ω is equivalent …


In-Depth Analysis Of College Students’ Data Privacy Awareness, Vernon D. Andrews Dec 2020

In-Depth Analysis Of College Students’ Data Privacy Awareness, Vernon D. Andrews

Theses and Dissertations

While attending university, college students need to be aware of issues related to data privacy. Regardless of the age, gender, race, or education level of college students, every student can relate to the advancement of the internet within the last decades. The internet has completely transformed the way the world receives and stores messages. Positively, the internet allows messages to be sent across the globe within the fraction of a second and provides students with access to potentially unlimited information on a variety of subjects. On the downside, there are issues on the internet that can cause more harm than …


Proactive Management In Academic Libraries: Promoting Improved Communication And Inclusion Of Academic Librarians And Archivists In Cybersecurity Policy Creation, Paul J. Luft Dec 2020

Proactive Management In Academic Libraries: Promoting Improved Communication And Inclusion Of Academic Librarians And Archivists In Cybersecurity Policy Creation, Paul J. Luft

Theses and Dissertations

Although increasing cybersecurity threats continue in libraries, not many studies are available which examine surrounding cybersecurity policies. Even less has been done on specific types of libraries such as academic and archives. When it comes to academic libraries, cybersecurity policies take a top-down approach to managing and creating policies. The problem is that both academic libraries and archives are unique areas within a university setting. Some of the general policies do not always handle specific issues dealt with in an academic library or archives. This paper investigates if an actual gap or void in policy exists which could create issues …