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Articles 69571 - 69600 of 294560

Full-Text Articles in Physical Sciences and Mathematics

Fault Detection In A Smart Electric Grid: Geometric Analysis, Hector Reyes, Dillon Trinh, Vladik Kreinovich Nov 2021

Fault Detection In A Smart Electric Grid: Geometric Analysis, Hector Reyes, Dillon Trinh, Vladik Kreinovich

Departmental Technical Reports (CS)

The main idea behind a smart grid is to equip the grid with a dense lattice of sensors monitoring the state of the grid. If there is a fault, the sensors closer to the fault will detect larger deviations from the normal readings that sensors that are farther away. In this paper, we show that this fact can be used to locate the fault with high accuracy.

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Why Geological Regions?, Daniela Flores, Olga Kosheleva, Vladik Kreinovich Nov 2021

Why Geological Regions?, Daniela Flores, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In most practical applications, we approximate the spatial dependence by smooth functions. The main exception is geosciences, where, to describe, e.g., how the density depends on depth and/or on spatial location, geophysicists divide the area into regions on each of which the corresponding quantity is approximately constant. In this paper, we provide a possible explanation for this difference.

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Why People Overestimate Small Probabilities?, David Amparan, Vladik Kreinovich Nov 2021

Why People Overestimate Small Probabilities?, David Amparan, Vladik Kreinovich

Departmental Technical Reports (CS)

It is a known empirical fact that people overestimate small probabilities. This fact seems to be inconsistent with the fact that we humans are the product of billions years of improving evolution -- and that we therefore perceive the world as accurately as possible. In this paper, we provide a possible explanation for this seeming contradiction.

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Why Rectified Linear Neurons: A Possible Interval-Based Explanation, Jonathan Contreras, Martine Ceberio, Vladik Kreinovich Nov 2021

Why Rectified Linear Neurons: A Possible Interval-Based Explanation, Jonathan Contreras, Martine Ceberio, Vladik Kreinovich

Departmental Technical Reports (CS)

At present, the most efficient machine learning techniques are deep neural networks. In these networks, a signal repeatedly undergoes two types of transformations: linear combination of inputs, and a non-linear transformation of each value v -> s(v). Empirically, the function s(v) = max(v,0) -- known as the rectified linear function -- works the best. There are some partial explanations for this empirical success; however, none of these explanations is fully convincing. In this paper, we analyze this why-question from the viewpoint of uncertainty propagation. We show that reasonable uncertainty-related arguments lead to another possible explanation of why rectified linear functions …

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How Probabilistic Methods For Data Fitting Deal With Interval Uncertainty: A More Realistic Analysis, Vladik Kreinovich, Sergey P. Shary Nov 2021

How Probabilistic Methods For Data Fitting Deal With Interval Uncertainty: A More Realistic Analysis, Vladik Kreinovich, Sergey P. Shary

Departmental Technical Reports (CS)

In our previous paper, we showed that a simplified probabilistic approach to interval uncertainty leads to the known notion of a united solution set. In this paper, we show that a more realistic probabilistic analysis of data fitting under interval uncertainty leads to another known notion -- the notion of a tolerable solution set. Thus, the notion of a tolerance solution set also has a clear probabilistic interpretation. Good news is that, in contrast to the united solution set whose computation is, in general, NP-hard, the tolerable solution set can be computed by a feasible algorithm.

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Beluga Whale (Delphinapterus Leucas) Acoustic Foraging Behavior And Applications For Long Term Monitoring, Manuel Castellote, Aran Mooney, Russel Andrews, Stacy L. Deruiter Nov 2021

Beluga Whale (Delphinapterus Leucas) Acoustic Foraging Behavior And Applications For Long Term Monitoring, Manuel Castellote, Aran Mooney, Russel Andrews, Stacy L. Deruiter

University Faculty Publications and Creative Works

Cook Inlet, Alaska, is home to an endangered and declining population of 279 belugas (Delphinapterus leucas). Recovery efforts highlight a paucity of basic ecological knowledge, impeding the correct assessment of threats and the development of recovery actions. In particular, information on diet and foraging habitat is very limited for this population. Passive acoustic monitoring has proven to be an efficient approach to monitor beluga distribution and seasonal occurrence. Identifying acoustic foraging behavior could help address the current gap in information on diet and foraging habitat. To address this conservation challenge, eight belugas from a comparative, healthy population in Bristol Bay, …

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Developing An International Framework For Addressing Non-State Actors In Cyberspace, Joanna C. Di Scipio Nov 2021

Developing An International Framework For Addressing Non-State Actors In Cyberspace, Joanna C. Di Scipio

Cybersecurity Undergraduate Research Showcase

On May 7, 2021, Colonial Pipeline shut down its operations following a ransomware attack by the criminal group DarkSide (Bordoff, 2021). It took five days to resume normal operations, but this short period led to panic buying, rising prices, and significant gas shortages. The attack underscores an emerging threat in the landscape of cybersecurity: critical infrastructure attacks carried out by non-state actors.

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Self-Supervised Perceptual Ad-Blocker, Killian Robinson Nov 2021

Self-Supervised Perceptual Ad-Blocker, Killian Robinson

Cybersecurity Undergraduate Research Showcase

This project proposes a new self-supervised ad-blocker to minimize the amount of human effort required to effectively combat pushed advertisements. Current ad-blocker models are expensive to develop and not always effective in identifying advertisements. We investigated the possibility of solving these problems with the introduction of a deep learning, self-supervised ad-blocker model. More specifically, the proposed ad-blocker will be trained in a self-supervised fashion to tackle the issue of lacking labelled training data. The proposed solution was prototyped using Pytorch and achieved a detection accuracy of 81% on a diverse selection of popular websites.

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Protection Of Patient Privacy On Mobile Device Machine Learning, Matthew Nguyen Nov 2021

Protection Of Patient Privacy On Mobile Device Machine Learning, Matthew Nguyen

Cybersecurity Undergraduate Research Showcase

An existing StudentLife Study mobile dataset was evaluated and organized to be applied to different machine learning methods. Different variables like user activity, exercise, sleep, study space, social, and stress levels are optimized to train a model that could predict user stress level. The different machine learning methods would test if both patient data privacy and training efficiency can be ensured.

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How Secure Are Android And Apple’S Operating Systems And Based Applications Against Cyber Attacks And Cyber Crime, Marlowe Cosby Jr. Nov 2021

How Secure Are Android And Apple’S Operating Systems And Based Applications Against Cyber Attacks And Cyber Crime, Marlowe Cosby Jr.

Cybersecurity Undergraduate Research Showcase

Smartphone has become an important part of our everyday life. Android and apple are the two most used operating system (OS) for smart phones. We usually store important information in our smart phone, e.g.: credit card, bank account, driving ID, SSN. As a result, Android and Apple operating systems and applications have both been subject to a wide number of vulnerabilities and attacks. This directly effects many people being that they are the global leaders of users within their platforms reaching billions of people daily. It is important that smartphones receive better defense and security. In this paper, we aim …

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Cybersecurity Maturity Model Certification (Cmmc) Compliance For Dod Contractors, Sierra Burnett Nov 2021

Cybersecurity Maturity Model Certification (Cmmc) Compliance For Dod Contractors, Sierra Burnett

Cybersecurity Undergraduate Research Showcase

The DoD is currently taking a supply-chain risk management strategy to foster cybersecurity. This unique strategy is often referred to as CMMC which stands for “Cybersecurity Maturity Model Certification”. The approach requires that all the 300,000 DoD contractors acquire third-party authentication that may attain the requirements for the CMMC maturity level suitable to the work they desire to do for the DoD. CMMC typically examines the organization's capability to safeguard Federal Contract Information as well as CUI. It integrates various cybersecurity standards already in place and plots the best practices alongside processes to five maturity levels that range from the …

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Internet Of Things: Cybersecurity In Small Businesses, Zobair Wali Nov 2021

Internet Of Things: Cybersecurity In Small Businesses, Zobair Wali

Cybersecurity Undergraduate Research Showcase

Small businesses are the most vital part of a nation’s economy. In today’s world, as we are moving towards digitizing almost everything around us, cybersecurity is essential and vital for our digitalized world to function. Small businesses are no exception. All businesses collect, use, and store information. They store employees’ information, tax information, customers’ information, business transaction information, and all other operational information that is needed for a business to function. Without an appropriate cybersecurity program, these businesses are vulnerable and can be easily impacted by cyber incidents and malicious attacks. Businesses are putting resources to protect their systems against …

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Adsorption Of Perfluorooctanoic Acid (Pfoa) And Perfluorooctanesulfonic Acid (Pfos) By Aluminum-Based Drinking Water Treatment Residuals, Zhiming Zhang, Dibyendu Sarkar, Rupali Datta, Yang Deng Nov 2021

Adsorption Of Perfluorooctanoic Acid (Pfoa) And Perfluorooctanesulfonic Acid (Pfos) By Aluminum-Based Drinking Water Treatment Residuals, Zhiming Zhang, Dibyendu Sarkar, Rupali Datta, Yang Deng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Per- and polyfluoroalkyl substances (PFAS) represent a family of emerging persistent organic pollutants. Cost-effective remediation of PFAS contamination via chemical or biochemical degradation is challenging due to their extremely high stability. This study reports the removal of two representative PFAS species, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), from water by adsorption using aluminum-based water treatment residuals (Al-WTR), a non-hazardous waste generated during the process of drinking water treatment by alum salts. Rapid adsorption of PFOA and PFOS onto Al-WTR followed a pseudo 2nd order kinetic pattern. Lower pH facilitated the adsorption process with a faster adsorption rate and greater …

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Pollution In Rainwater Harvesting: A Challenge For Sustainability And Resilience Of Urban Agriculture, Yang Deng Nov 2021

Pollution In Rainwater Harvesting: A Challenge For Sustainability And Resilience Of Urban Agriculture, Yang Deng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Water plays a pivotal role in urban agriculture. Although rainwater harvesting (RWH) is viewed as a sustainable route for crop irrigation at an urban setting, rainwater contaminants challenge the RWH practices due to potential threats to the health of crops, soil, and human (i.e., farm workers and food consumers). This frontier review article first recognized principal pollutants of irrigation concern in harvested rainwater based on literature data and crop irrigation demands. Major traditional pollutants, likely exceeding irrigation quality criteria, include particles, some toxic metals (e.g., Cd, Cu, and Zn), certain synthetic organic chemicals (e.g., agrochemicals and polycyclic aromatic hydrocarbons), and …

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Felsic Volcanism As A Factor Driving The End-Permian Mass Extinction, Hua Zhang, Feifei Zhang, Jiu Bin Chen, Douglas H. Erwin, Drew D. Syverson, Pei Ni, Michael Rampino, Zhe Chi, Yao Feng Cai, Lei Xiang, Wei Qiang Li, Sheng Ao Liu, Ru Cheng Wang, Xiang Dong Wang, Zhuo Feng, Hou Min Li, Ting Zhang, Hong Ming Cai, Wang Zheng, Ying Cui, Xiang Kun Zhu, Zeng Qian Hou, Fu Yuan Wu, Yi Gang Xu, Noah Planavsky, Shu Zhong Shen Nov 2021

Felsic Volcanism As A Factor Driving The End-Permian Mass Extinction, Hua Zhang, Feifei Zhang, Jiu Bin Chen, Douglas H. Erwin, Drew D. Syverson, Pei Ni, Michael Rampino, Zhe Chi, Yao Feng Cai, Lei Xiang, Wei Qiang Li, Sheng Ao Liu, Ru Cheng Wang, Xiang Dong Wang, Zhuo Feng, Hou Min Li, Ting Zhang, Hong Ming Cai, Wang Zheng, Ying Cui, Xiang Kun Zhu, Zeng Qian Hou, Fu Yuan Wu, Yi Gang Xu, Noah Planavsky, Shu Zhong Shen

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The Siberian Traps large igneous province (STLIP) is commonly invoked as the primary driver of global environmental changes that triggered the end-Permian mass extinction (EPME). Here, we explore the contributions of coeval felsic volcanism to end-Permian environmental changes. We report evidence of extreme Cu enrichment in the EPME interval in South China. The enrichment is associated with an increase in the light Cu isotope, melt inclusions rich in copper and sulfides, and Hg concentration spikes. The Cu and Hg elemental and isotopic signatures can be linked to S-rich vapor produced by felsic volcanism. We use these previously unknown geochemical data …

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The Ionic Selectivity Of Lysenin Channels In Open And Sub-Conducting States, Andrew Bogard, Pangaea W. Finn, Fulton Mckinney, Ilinca M. Flacau, Aviana R. Smith, Rosey Whiting, Daniel Fologea Nov 2021

The Ionic Selectivity Of Lysenin Channels In Open And Sub-Conducting States, Andrew Bogard, Pangaea W. Finn, Fulton Mckinney, Ilinca M. Flacau, Aviana R. Smith, Rosey Whiting, Daniel Fologea

Physics Faculty Publications and Presentations

The electrochemical gradients established across cell membranes are paramount for the execution of biological functions. Besides ion channels, other transporters, such as exogenous pore-forming toxins, may present ionic selectivity upon reconstitution in natural and artificial lipid membranes and contribute to the electrochemical gradients. In this context, we utilized electrophysiology approaches to assess the ionic selectivity of the pore-forming toxin lysenin reconstituted in planar bilayer lipid membranes. The membrane voltages were determined from the reversal potentials recorded upon channel exposure to asymmetrical ionic conditions, and the permeability ratios were calculated from the fit with the Goldman–Hodgkin–Katz equation. Our work shows that …

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Automated Detection Of Marine Glacier Calving Fronts Using The 2-D Wavelet Transform Modulus Maxima Segmentation Method, Julia Liu, Ellyn M. Enderlin, Hans-Peter Marshall, Andre Khalil Nov 2021

Automated Detection Of Marine Glacier Calving Fronts Using The 2-D Wavelet Transform Modulus Maxima Segmentation Method, Julia Liu, Ellyn M. Enderlin, Hans-Peter Marshall, Andre Khalil

Geosciences Faculty Publications and Presentations

Changes in the calving front position of marine-terminating glaciers strongly influence the mass balance of glaciers, ice caps, and ice sheets. At present, quantification of frontal position change primarily relies on time-consuming and subjective manual mapping techniques, limiting our ability to understand changes to glacier calving fronts. Here we describe a newly developed automated method of mapping glacier calving fronts in satellite imagery using observations from a representative sample of Greenland’s peripheral marine-terminating glaciers. Our method is adapted from the 2-D wavelet transform modulus maxima (WTMM) segmentation method, which has been used previously for image segmentation in biomedical and other …

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Homflypt Skein Theory, String Topology And 2-Categories, Uwe Kaiser Nov 2021

Homflypt Skein Theory, String Topology And 2-Categories, Uwe Kaiser

Mathematics Faculty Publications and Presentations

We show that relations in Homflypt type skein theory of an oriented 3-manifold M are induced from a 2-groupoid defined from the fundamental 2-groupoid of a space of singular links M. The module relations are defined by homomorphisms related to string topology. They appear from a representation of the groupoid into free modules on a set of model objects. The construction on the fundamental 2-groupoid is defined by the singularity stratification and relates Vassiliev and skein theory. Several explicit properties are discussed, and some implications for skein modules are derived.

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Risk Management And Biases In How Drivers Respond To Nuisance Flooding, Saige Hill, Juita-Elena (Wie) Yusuf, Burton St. John Iii, Pragati Rawat, Carol Considine Nov 2021

Risk Management And Biases In How Drivers Respond To Nuisance Flooding, Saige Hill, Juita-Elena (Wie) Yusuf, Burton St. John Iii, Pragati Rawat, Carol Considine

School of Public Service Faculty Publications

Nuisance flooding, or recurrent flooding, occurs during high tide and may be exacerbated when combined with other events such as heavy precipitation, strong winds, or storm surge. Sea level rise has contributed to increased frequency and duration of nuisance flooding in low-lying coastal areas and is causing community-specific impacts such as transportation disruption, road closures, compromises to life and property, overwhelmed storm water systems, and infrastructure damage. This chapter focuses on how drivers respond during nuisance flooding events. Specifically, we discuss how drivers in the Hampton Roads region of southeastern coastal Virginia obtain information about road flooding, how they respond, …

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Silica Sinter And The Evolution Of Hot Springs In The Alvord/Pueblo Valleys, Southeast Oregon, Usa, Leslie Allen Mowbray, Michael L. Cummings Nov 2021

Silica Sinter And The Evolution Of Hot Springs In The Alvord/Pueblo Valleys, Southeast Oregon, Usa, Leslie Allen Mowbray, Michael L. Cummings

Geology Faculty Publications and Presentations

Hot springs in the Alvord/Pueblo valleys in southeastern Oregon are analogous to Basinand- Range hydrothermal systems where heat source and permeable pathways are met through crustal thinning. Silica sinter deposition at Mickey Springs, Alvord Valley, predates the late Pleistocene high stand of pluvial Lake Alvord. At Borax Lake, Pueblo Valley, sinter deposition occurred during the Holocene. This study examines the evolution of springs at Mickey Springs, where three morphologies of sinter are present: (1) basalt clasts surrounded by sinter in interbedded conglomerate and sandstone, (2) pool-edge and aprons of sinter surrounding depressions (12–32 m diameter), and (3) quaquaversal sinter mounds …

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2021 November - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University Nov 2021

2021 November - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.

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Spatiotemporal Variations In Liquid Water Content In A Seasonal Snowpack: Implications For Radar Remote Sensing, Randall Bonnell, Daniel Mcgrath, Keith Williams, Ryan Webb, Steven R. Fassnacht, Hans-Peter Marshall Nov 2021

Spatiotemporal Variations In Liquid Water Content In A Seasonal Snowpack: Implications For Radar Remote Sensing, Randall Bonnell, Daniel Mcgrath, Keith Williams, Ryan Webb, Steven R. Fassnacht, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

Radar instruments have been widely used to measure snow water equivalent (SWE) and Interferometric Synthetic Aperture Radar is a promising approach for doing so from spaceborne platforms. Electromagnetic waves propagate through the snowpack at a velocity determined by its dielectric permittivity. Velocity estimates are a significant source of uncertainty in radar SWE retrievals, especially in wet snow. In dry snow, velocity can be calculated from relations between permittivity and snow density. However, wet snow velocity is a function of both snow density and liquid water content (LWC); the latter exhibits high spatiotemporal variability, there is no standard observation method, and …

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In Situ Determination Of Dry And Wet Snow Permittivity: Improving Equations For Low Frequency Radar Applications, Ryan Webb, Adrian Marziliano, Daniel Mcgrath, Randall Bonnell, Tate G. Meehan, Carrie Vuyovich, Hans-Peter Marshall Nov 2021

In Situ Determination Of Dry And Wet Snow Permittivity: Improving Equations For Low Frequency Radar Applications, Ryan Webb, Adrian Marziliano, Daniel Mcgrath, Randall Bonnell, Tate G. Meehan, Carrie Vuyovich, Hans-Peter Marshall

Geosciences Faculty Publications and Presentations

Extensive efforts have been made to observe the accumulation and melting of seasonal snow. However, making accurate observations of snow water equivalent (SWE) at global scales is challenging. Active radar systems show promise, provided the dielectric properties of the snowpack are accurately constrained. The dielectric constant (k) determines the velocity of a radar wave through snow, which is a critical component of time-of-flight radar techniques such as ground penetrating radar and interferometric synthetic aperture radar (InSAR). However, equations used to estimate k have been validated only for specific conditions with limited in situ validation for seasonal snow applications. …

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Artificial Intelligence As Augmenting Automation: Implications For Employment, F. Ted Tschang, Esteve Almirall Nov 2021

Artificial Intelligence As Augmenting Automation: Implications For Employment, F. Ted Tschang, Esteve Almirall

Research Collection Lee Kong Chian School Of Business

There has been great concern in recent years that artificial intelligence (AI) may cause widespread unemployment, but proponents say that AI augments existing jobs. Both of these positions have substance, but there is a need is to articulate the mechanisms by which AI may actually do both, and in the process, transform work and business organizations alike. We use economic studies showing past transformations automation wrought on the structure of employment and skills (such as the favouring of nonroutine skills) to articulate a ground for discussion. We then use case evidence of AI and automation to show how AI is …

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Facile Synthesis Of Tertiary Amine Pendant Polymers By Cu0-Mediated Atrp Under Aqueous Conditions, Collin M. Britten, Kristen Lason, Keisha Walters Nov 2021

Facile Synthesis Of Tertiary Amine Pendant Polymers By Cu0-Mediated Atrp Under Aqueous Conditions, Collin M. Britten, Kristen Lason, Keisha Walters

Chemical Engineering Faculty Publications and Presentations

Cu0-mediated atom transfer radical polymerization (ATRP) in aqueous media is extended to tertiary amine-pendant methacrylate polymers with poly([2-dimethylamino]ethyl methacrylate) (PDMAEMA) serving as a model polymer. By increasing the concentration of deactivating CuII species, reducing the reaction temperature, and increasing the supporting halide concentration to 1 M, polymers with well-defined molecular weight distributions (MWDs) are achieved in under 4 h. MWDs show good agreement with theoretical values, with polydispersity indices (Đ) as low as 1.14. Furthermore, this reaction system shows a remarkable tolerance to dissolved oxygen, with little to no deleterious effects observed for polymerizations run …

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Informing Wetland Management With Waterfowl Movement And Sanctuary Use Responses To Human-Induced Disturbance, Fiona Mcduie, Austen A. Lorenz, Robert C. Klinger, Cory T. Overton, Cliff L. Feldheim, Joshua T. Ackerman, Michael L. Casazza Nov 2021

Informing Wetland Management With Waterfowl Movement And Sanctuary Use Responses To Human-Induced Disturbance, Fiona Mcduie, Austen A. Lorenz, Robert C. Klinger, Cory T. Overton, Cliff L. Feldheim, Joshua T. Ackerman, Michael L. Casazza

Faculty Research, Scholarly, and Creative Activity

Long-term environmental management to prevent waterfowl population declines is informed by ecology, movement behavior and habitat use patterns. Extrinsic factors, such as human-induced disturbance, can cause behavioral changes which may influence movement and resource needs, driving variation that affects management efficacy. To better understand the relationship between human-based disturbance and animal movement and habitat use, and their potential effects on management, we GPS tracked 15 dabbling ducks in California over ~4-weeks before, during and after the start of a recreational hunting season in October/November 2018. We recorded locations at 2-min intervals across three separate 24-h tracking phases: Phase 1) two …

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On The Relationship Between Pain Variability And Relief In Randomized Clinical Trials, Siddharth Tiwari '22 Nov 2021

On The Relationship Between Pain Variability And Relief In Randomized Clinical Trials, Siddharth Tiwari '22

Student Publications & Research

Previous research suggests greater baseline variability is associated with greater pain relief in those who receive a placebo. However, studies that evidence this association do not control for confounding effects (natural history and regression-to-the-mean); for this reason, we analyzed data from two randomized clinical trials (Placebo I and Placebo II, N = 134) while adjusting for confounding effects via a no-treatment group. Results agree between the two placebo groups: both placebo groups showed a negligible correlation between baseline variability and adjusted response (r sp (CI 95% ) = 0.13 (−0.09, 0.37) and 0.01 (−0.15, 0.20) for Placebo I and II, …

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Global 3d Radiation Hydrodynamic Simulations Of Proto-Jupiter’S Convective Envelope, Zhaohuan Zhu, Yan-Fei Jiang, Hans Baehr, Andrew N. Youdin, Philip J. Armitage, Rebecca G. Martin Nov 2021

Global 3d Radiation Hydrodynamic Simulations Of Proto-Jupiter’S Convective Envelope, Zhaohuan Zhu, Yan-Fei Jiang, Hans Baehr, Andrew N. Youdin, Philip J. Armitage, Rebecca G. Martin

Physics & Astronomy Faculty Research

The core accretion model of giant planet formation has been challenged by the discovery of recycling flows between the planetary envelope and the disc that can slow or stall envelope accretion. We carry out 3D radiation hydrodynamic simulations with an updated opacity compilation to model the proto-Jupiter’s envelope. To isolate the 3D effects of convection and recycling, we simulate both isolated spherical envelopes and envelopes embedded in discs. The envelopes are heated at given rates to achieve steady states, enabling comparisons with 1D models. We vary envelope properties to obtain both radiative and convective solutions. Using a passive scalar, we …

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Analysis Of The Photodegradation Of The Pro-Herbicide Benzobicyclon Hydrolysate Using A Seawater Gradient And Constituent Ions, Margaret A. Knight Nov 2021

Analysis Of The Photodegradation Of The Pro-Herbicide Benzobicyclon Hydrolysate Using A Seawater Gradient And Constituent Ions, Margaret A. Knight

Honors Capstones

No abstract provided.

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Search Full Text Options Here 1 Of 1 Constraints From Ligo O3 Data On Gravitational-Wave Emission Due To R-Modes In The Glitching Pulsar Psr J0537-6910, R. Abbott, T. D. Abbott Nov 2021

Search Full Text Options Here 1 Of 1 Constraints From Ligo O3 Data On Gravitational-Wave Emission Due To R-Modes In The Glitching Pulsar Psr J0537-6910, R. Abbott, T. D. Abbott

Faculty Publications

We present a search for continuous gravitational-wave emission due to r-modes in the pulsar PSR J0537-6910 using data from the LIGO-Virgo Collaboration observing run O3. PSR J0537-6910 is a young energetic X-ray pulsar and is the most frequent glitcher known. The inter-glitch braking index of the pulsar suggests that gravitational-wave emission due to r-mode oscillations may play an important role in the spin evolution of this pulsar. Theoretical models confirm this possibility and predict emission at a level that can be probed by ground-based detectors. In order to explore this scenario, we search for r-mode emission in the epochs between …

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