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2020

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Full-Text Articles in Physical Sciences and Mathematics

Extending Import Detection Algorithms For Concept Import From Two To Three Biomedical Terminologies, Vipina K. Keloth, James Geller, Yan Chen, Julia Xu Dec 2020

Extending Import Detection Algorithms For Concept Import From Two To Three Biomedical Terminologies, Vipina K. Keloth, James Geller, Yan Chen, Julia Xu

Publications and Research

Background: While enrichment of terminologies can be achieved in different ways, filling gaps in the IS-A hierarchy backbone of a terminology appears especially promising. To avoid difficult manual inspection, we started a research program in 2014, investigating terminology densities, where the comparison of terminologies leads to the algorithmic discovery of potentially missing concepts in a target terminology. While candidate concepts have to be approved for import by an expert, the human effort is greatly reduced by algorithmic generation of candidates. In previous studies, a single source terminology was used with one target terminology.

Methods: In this paper, we are extending …


Eureka Moment As Divine Spark In The Light Of Direct Experience With The Spirit And Nature, Victor Christianto, Florentin Smarandache Dec 2020

Eureka Moment As Divine Spark In The Light Of Direct Experience With The Spirit And Nature, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In the ancient world, the Greeks believed that all great insights came from one of nine muses, divine sisters who brought inspiration to mere mortals. In the modern world, few people still believe in the muses, but we all still love to hear stories of sudden inspiration. Like Newton and the apple, or Archimedes and the bathtub (both another type of myth), we’re eager to hear and to share stories about flashes of insight. But what does it take to be actually creative? How to have such a flash insight? Turns out, there is real science behind "aha moments." We …


Destabilizing Effects On A Classic Tri-Trophic Oyster Reef Cascade, Virginia R. Schweiss, Chet F. Rakocinski Dec 2020

Destabilizing Effects On A Classic Tri-Trophic Oyster Reef Cascade, Virginia R. Schweiss, Chet F. Rakocinski

Faculty Publications

How interactions among multiple predators affect the stability of trophic cascades is a topic of special ecological interest. To examine factors affecting the stability of the classic tri-trophic oyster reef cascade within a different context, configurations of three predators, including the Gulf toadfish, Gulf stone crab, and oystershell mud crab, were manipulated together with either oyster shell or limestone gravel substrate within a multiple predator effects (MPE) experiment. Additionally, a complimentary set of trait-mediated-indirect interaction (TMII) experiments examined the inhibition of oyster consumption relative to mud-crab size and top predator identity in the absence of other cues and factors. The …


Robustness Of Baryon Acoustic Oscillation Constraints For Early-Universe Modifications Of Λcdm Cosmology, J. L. Bernal, Tristan L. Smith, K. K. Boddy, M. Kamionkowski Dec 2020

Robustness Of Baryon Acoustic Oscillation Constraints For Early-Universe Modifications Of Λcdm Cosmology, J. L. Bernal, Tristan L. Smith, K. K. Boddy, M. Kamionkowski

Physics & Astronomy Faculty Works

Baryon acoustic oscillations (BAO) provide a robust standard ruler and can be used to constrain the expansion history of the Universe at low redshift. Standard BAO analyses return a model-independent measurement of the expansion rate and the comoving angular diameter distance as a function of redshift, normalized by the sound horizon at radiation drag. However, this methodology relies on anisotropic distance distortions of a fixed, precomputed template (obtained in a given fiducial cosmology) in order to fit the observations. Therefore, it may be possible that extensions to the consensus ΛCDM add contributions to the BAO feature that cannot be captured …


Saudi Elementary Mathematics Teachers’ Knowledge For Teaching Fractions, Mona Khalifah A Aladil Dec 2020

Saudi Elementary Mathematics Teachers’ Knowledge For Teaching Fractions, Mona Khalifah A Aladil

Dissertations

Recent reform efforts in Saudi Arabia attend to mathematics instruction with a great deal of emphasis to improve Saudi mathematics education. Studies in different countries have confirmed that teachers’ mathematical knowledge for teaching plays an important role in mathematical quality of instruction and students’ achievement (e.g., Ball, 1990; Baumert et al., 2010; Hill, Rowan, & Ball, 2005). Yet few studies about mathematics teachers’ knowledge for teaching have been conducted in the Saudi context. This study investigates Saudi elementary mathematics teachers’ knowledge for teaching in the content strand of rational numbers with an emphasis on fractions, which is an important step …


Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy Dec 2020

Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy

Electronic Theses and Dissertations

The Arizona toad (Anaxyrus microscaphus) and Jones’ waxy dogbane (Cycladenia humilis var. jonesii) are habitat specialists with historical ranges in the desert southwest and specifically, Zion National Park (ZION). The machine learning method, MaxEnt, constructed species distribution models (SDMs) in ZION for the two study species at 30 m and 900 m spatial resolutions using climate, topographic, and remotely sensed data. Additionally, 900 m forecasting models were constructed to observe the shifts in suitable habitat for the years 2050 and 2070, based off two representative concentration pathway scenarios. Results indicate promising predictive power for both high …


Growing Quelites In The City: Exploration On Memory And Food Sovereignty In Mexico City, Paola Valeria Ramirez Ensastiga Dec 2020

Growing Quelites In The City: Exploration On Memory And Food Sovereignty In Mexico City, Paola Valeria Ramirez Ensastiga

Masters Theses

In Mexico, as in the world, the number of people living in urban areas is increasing. In addition, urbanization directly generates a fragmentation of the natural habitat and causes the loss of biodiversity. Native edible crops are also being threatened by a constant decline in biodiversity, causing negative ecological, economic and even cultural impact. Until now, the main guardians of the edible biodiversity have been indigenous peoples. Several authors agree that the way in which indigeous people relate to nature may shed some light on how to face the ecological and climate crisis that we are experiencing today. I argue …


Upper Limit Of Electron Fluxes Observed In The Radiation Belts, Kun Zhang, Xinlin Li, Hong Zhao, Zheng Xiang, Leng Ying Khoo, Wenxun Zhang, Benjamin Hogan, Michael A. Temerin Dec 2020

Upper Limit Of Electron Fluxes Observed In The Radiation Belts, Kun Zhang, Xinlin Li, Hong Zhao, Zheng Xiang, Leng Ying Khoo, Wenxun Zhang, Benjamin Hogan, Michael A. Temerin

Publications

Radiation belt electrons have a complicated relationship with geomagnetic activity. We select electron measurements from 7 years of DEMETER and 6 years of Van Allen Probes data during geomagnetic storms to conduct statistical analysis focusing on the correlation between electron flux and Dst index. We report, for the first time, an upper limit of electron fluxes observed by both satellites throughout the inner and outer belts across a wide energy range from ∼100s keV to multi-MeV. The upper flux limit is determined at different L's and energies, for example, 1.9 × 107/cm2-s-sr-MeV at 470 keV at L = 1.5 and …


Hardness Of Reconfiguring Robot Swarms With Uniform External Control In Limited Directions, David Caballero, Angel A. Cantu, Timothy Gomez, Austin Luchsinger, Robert Schweller, Tim Wylie Dec 2020

Hardness Of Reconfiguring Robot Swarms With Uniform External Control In Limited Directions, David Caballero, Angel A. Cantu, Timothy Gomez, Austin Luchsinger, Robert Schweller, Tim Wylie

Computer Science Faculty Publications

Motivated by advances is nanoscale applications and simplistic robot agents, we look at problems based on using a global signal to move all agents when given a limited number of directional signals and immovable geometry. We study a model where unit square particles move within a 2D grid based on uniform external forces. Movement is based on a sequence of uniform commands which cause all particles to move 1 step in a specific direction. The 2D grid board additionally contains \blocked" spaces which prevent particles from entry. Within this model, we investigate the complexity of deciding 1) whether a target …


Synthesis Of Linear Oligo[N]Catenanes Via Orthogonal Metal Templation, Nathan Colley Dec 2020

Synthesis Of Linear Oligo[N]Catenanes Via Orthogonal Metal Templation, Nathan Colley

Arts & Sciences Graduate Student Theses and Dissertations

No abstract provided.


Flow Patterns, Velocity Distributions And Mixing Time In Stirred Tank Reactor Under A Range Of Operating Conditions, Nor Haslina Abdullah Dec 2020

Flow Patterns, Velocity Distributions And Mixing Time In Stirred Tank Reactor Under A Range Of Operating Conditions, Nor Haslina Abdullah

Student Works (2020-2029)

The present work employed a two-dimensional Particle Imaging Velocimetry (PIV) technique to determine the flow patterns and velocity distributions of a down-pumping pitched-blade turbine (4PB) and a Rushton turbine (RT) in a flat-bottom fully baffled stirred vessel (T=0.155m) using distilled water and glycerin as liquids. Fluid velocities increased as the impeller speed increased from 50rpm to 300rpm for both fluids and the RT impeller reached a maximum value of velocity of 1.42m/s at the blade tip. The 4PB had higher velocity compared to RT in glycerin, but RT had higher velocity than 4PB in distilled water. In water, radial flow …


A Test Of Grazing Experimental Design And Grazing Effects In A Mixed Grassland Ecosystem, Xiaohui Yang, Xulin Guo Dec 2020

A Test Of Grazing Experimental Design And Grazing Effects In A Mixed Grassland Ecosystem, Xiaohui Yang, Xulin Guo

IGC Proceedings (1977-2023)

No abstract provided.


Sheep Production On High Desert Rangelands And Irrigated Pasture, Tumen Wuliji, Hudson Glimp, Barry L. Perryman, Wendy Rauw, Tom Filbin Dec 2020

Sheep Production On High Desert Rangelands And Irrigated Pasture, Tumen Wuliji, Hudson Glimp, Barry L. Perryman, Wendy Rauw, Tom Filbin

IGC Proceedings (1977-2023)

No abstract provided.


Grazing Management For The Tropical Savannas Of Northern Australia: Utilisation Rates And Timing Of Spelling, Andrew I. White, L. P. Hunt, S. R. Petty, Dennis P. Poppi Dec 2020

Grazing Management For The Tropical Savannas Of Northern Australia: Utilisation Rates And Timing Of Spelling, Andrew I. White, L. P. Hunt, S. R. Petty, Dennis P. Poppi

IGC Proceedings (1977-2023)

No abstract provided.


L_P_ Approximation By Relu Neural Networks, Eman Samir Bhaya, Zainab Abdulmunim Sharba Dec 2020

L_P_ Approximation By Relu Neural Networks, Eman Samir Bhaya, Zainab Abdulmunim Sharba

Karbala International Journal of Modern Science

We know that we can use the neural networks for the approximation of functions for many types of activation functions. Here, we treat only neural networks with simple and particular activation function called rectified linear units (ReLU). The main aim of this paper is to introduce a type of constructive universal approximation theorem and estimate the error of the universal approximation. We will obtain optimal approximation if we have a basis independent of the target function. We prove a type of Debao Chen's theorem for approximation.


Twitter Fake Account Detection And Classification Using Ontological Engineering And Semantic Web Rule Language, Mohammed Jabardi, Asaad Sabah Hadi Dec 2020

Twitter Fake Account Detection And Classification Using Ontological Engineering And Semantic Web Rule Language, Mohammed Jabardi, Asaad Sabah Hadi

Karbala International Journal of Modern Science

Nowadays, Twitter has become one of the fastest-growing Online Social Networks (OSNs) for data sharing frameworks and microblogging. It attracts millions of users worldwide where subscribers communicate with each through posts and messages known as "tweets". The open structure and behaviour of Twitter cause it to be vulnerable to attacks from fake accounts and a large number of automated software, known as 'bots'. Bots are regarded to be malicious as they send spam to users of social networks over the internet. Data security and privacy are among the most critical issues of social network users, as the protection and fulfilment …


The Revised Nim For Solving The Non-Linear System Variant Boussinesq Equations And Comparison With Nim, Oday Ahmed Jasim Dec 2020

The Revised Nim For Solving The Non-Linear System Variant Boussinesq Equations And Comparison With Nim, Oday Ahmed Jasim

Karbala International Journal of Modern Science

This research aims to guide researchers to use a new method, and it is the Revised New Iterative Method (RNIM) to solve partial differential equation systems and apply them to solve problems in various disciplines such as chemistry, physics, engineering and medicine. In this paper, the numerical solutions of the nonlinear Variable Boussinesq Equation System (VBE) were obtained using a new modified iterative method (RNIM); this was planned by (Bhaleker and Datterder-Gejj). A numerical solution to the Variable Boussinesq Equation System (VBE) was also found using a widely known method, a new iterative method (NIM). By comparing the numerical solutions …


Editorial Board Dec 2020

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.


The Boundedness Of General Alternative Singular Integrals With Respect To The Gaussian Measure, Eduard Navas, Ebner Pineda, Wilfredo O. Urbina Dec 2020

The Boundedness Of General Alternative Singular Integrals With Respect To The Gaussian Measure, Eduard Navas, Ebner Pineda, Wilfredo O. Urbina

Journal of Stochastic Analysis

No abstract provided.


Two New Finite Element Schemes And Their Analysis For Modeling Of Wave Propagation In Graphene, Jichun Li Dec 2020

Two New Finite Element Schemes And Their Analysis For Modeling Of Wave Propagation In Graphene, Jichun Li

Mathematical Sciences Faculty Research

© 2020 The Author(s) In this paper, we investigate a system of governing equations for modeling wave propagation in graphene. Compared to our previous work (Yang et al., 2020), here we re-investigate the governing equations by eliminating two auxiliary unknowns from the original model. A totally new stability for the model is established for the first time. Since the finite element scheme proposed in Yang et al. (2020) is only first order in time, here we propose two new schemes with second order convergence in time for the simplified modeling equations. Discrete stabilities inheriting exactly the same form as the …


Sybil Defense Using Efficient Resource Burning, Diksha Gupta Dec 2020

Sybil Defense Using Efficient Resource Burning, Diksha Gupta

Computer Science ETDs

In 1993, Dwork and Naor proposed using computational puzzles, a resource burning mechanism, to combat spam email. In the ensuing three decades, resource burning has broadened to include communication capacity, computer memory, and human effort. It has become a well-established tool in distributed security. Due to the cost attached to utilizing resource burning mechanism, these have not been popularized in domains apart from cryptocurrency.

In this dissertation, we design efficient resource burning based Sybil defense techniques for permissionless systems. As a first step, we identify existing resource burning mechanisms in literature in Chapter 2. Additionally, we enumerate numerous open problems …


Outdoor Air Pollution Exposure And Inter-Relation Of Global Cognitive Performance And Emotional Distress In Older Women, Andrew J. Petkus, Xinhui Wang, Daniel P. Beavers, Helena C. Chui, Mark A. Espeland, Margaret Gatz, Tara Gruenewald, Joel D. Kaufman, Joann E. Manson, Susan M. Resnick, James D. Stewart, Gregory A. Wellenius, Eric A. Whitsel, Keith Widaman, Diana Younan, Jiu-Chiuan Chen Dec 2020

Outdoor Air Pollution Exposure And Inter-Relation Of Global Cognitive Performance And Emotional Distress In Older Women, Andrew J. Petkus, Xinhui Wang, Daniel P. Beavers, Helena C. Chui, Mark A. Espeland, Margaret Gatz, Tara Gruenewald, Joel D. Kaufman, Joann E. Manson, Susan M. Resnick, James D. Stewart, Gregory A. Wellenius, Eric A. Whitsel, Keith Widaman, Diana Younan, Jiu-Chiuan Chen

Psychology Faculty Articles and Research

The interrelationships among long-term ambient air pollution exposure, emotional distress and cognitive decline in older adulthood remain unclear. Long-term exposure may impact cognitive performance and subsequently impact emotional health. Conversely, exposure may initially be associated with emotional distress followed by declines in cognitive performance. Here we tested the inter-relationship between global cognitive ability, emotional distress, and exposure to PM2.5 (particulate matter with aerodynamic diameter 2 (nitrogen dioxide) in 6118 older women (aged 70.6 ± 3.8 years) from the Women’s Health Initiative Memory Study. Annual exposure to PM2.5 (interquartile range [IQR] = 3.37 μg/m3) and NO2 (IQR …


Fractal And Edge-Based Techniques For Kidney Enhancement And Segmentation On Magnetic Resonance Images (Mri), Alaá Rateb Mahmoud Al-Shamasneh Dec 2020

Fractal And Edge-Based Techniques For Kidney Enhancement And Segmentation On Magnetic Resonance Images (Mri), Alaá Rateb Mahmoud Al-Shamasneh

Student Works (2020-2029)

Recently, many rapid developments in digital medical imaging have made further contributions to healthcare systems. However, the segmentation of regions of interest in medical images plays a vital role in assisting doctors in their medical diagnoses and for the early detection of disease. Since health issues related to the kidneys are increasing exponentially, this thesis focused on developing methods for the segmentation of MRI images of the kidney. Kidney images frequently suffer from low contrast, low resolution and noise, and are blur. Hence, it is necessary to enhance the images in order to improve the segmentation. Therefore, the current thesis …


Short Term Variations In The Leaf Area Index, Tiller Density And Botanical Composition Of The Grassland In Inner Mongolia As Affected By Light To Very Heavy Grazing Intensities, H. Wan, P. Schönbach, M. Gierus, Anne Schiborra, Y. Bai, Friedhelm Taube Dec 2020

Short Term Variations In The Leaf Area Index, Tiller Density And Botanical Composition Of The Grassland In Inner Mongolia As Affected By Light To Very Heavy Grazing Intensities, H. Wan, P. Schönbach, M. Gierus, Anne Schiborra, Y. Bai, Friedhelm Taube

IGC Proceedings (1977-2023)

No abstract provided.


The Use Of Concentrate Supplements To Overcome Seasonal Shortages Of Grazed Herbage In Beef Production Systems, Valéria P. B. Euclides, Kepler Euclides Filho, Fernando Paim Costa, Alexandre Scaff Raffia Dec 2020

The Use Of Concentrate Supplements To Overcome Seasonal Shortages Of Grazed Herbage In Beef Production Systems, Valéria P. B. Euclides, Kepler Euclides Filho, Fernando Paim Costa, Alexandre Scaff Raffia

IGC Proceedings (1977-2023)

No abstract provided.


Effects Of Novel Ryegrass Endophytes On Pasture Production And Milk Production From Dairy Cows In Northern New Zealand, Errol R. Thom, C. D. Waugh, E. M. K. Minneé, G. C. Waghorn, Alison J. Popay Dec 2020

Effects Of Novel Ryegrass Endophytes On Pasture Production And Milk Production From Dairy Cows In Northern New Zealand, Errol R. Thom, C. D. Waugh, E. M. K. Minneé, G. C. Waghorn, Alison J. Popay

IGC Proceedings (1977-2023)

No abstract provided.


The Cottonwood Ranch Riparian Management Case Study, Sherman Swanson, Kent Mcadoo, Agee Smith, Sandra Wyman Dec 2020

The Cottonwood Ranch Riparian Management Case Study, Sherman Swanson, Kent Mcadoo, Agee Smith, Sandra Wyman

IGC Proceedings (1977-2023)

No abstract provided.


Grazing Itineraries And Feed Intake Of Goats On Communal Pastures Of The Jabal Al Akhdar Mountain Range, Northern Oman, E. Schlecht, U. Dickhoefer, M. Predotova, Andreas Buerkert Dec 2020

Grazing Itineraries And Feed Intake Of Goats On Communal Pastures Of The Jabal Al Akhdar Mountain Range, Northern Oman, E. Schlecht, U. Dickhoefer, M. Predotova, Andreas Buerkert

IGC Proceedings (1977-2023)

No abstract provided.


Timing Of Grazing Affects Sandhills Grassland Productivity And Diet Quality, W. H. Schacht, J. D. Volesky, P. R. Schroeder Dec 2020

Timing Of Grazing Affects Sandhills Grassland Productivity And Diet Quality, W. H. Schacht, J. D. Volesky, P. R. Schroeder

IGC Proceedings (1977-2023)

No abstract provided.


Ever Graze‐More Livestock From Perennials, Geoffrey Saul, Angela Avery Dec 2020

Ever Graze‐More Livestock From Perennials, Geoffrey Saul, Angela Avery

IGC Proceedings (1977-2023)

No abstract provided.