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2020

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Articles 271 - 300 of 15205

Full-Text Articles in Physical Sciences and Mathematics

Pharmaceuticals And Personal Care Products In Pacific Northwest Coastal Ecosystems: Spatial Variation, Organism Effects, And Consumer Perspectives, Amy Lynne Ehrhart Dec 2020

Pharmaceuticals And Personal Care Products In Pacific Northwest Coastal Ecosystems: Spatial Variation, Organism Effects, And Consumer Perspectives, Amy Lynne Ehrhart

Dissertations and Theses

Anthropogenic pollution poses a threat to marine organisms and ecosystems worldwide. Common chemical pollutants that enter the marine environment include legacy contaminants, which are well known and heavily regulated or banned pollutants, and emerging contaminants, which are more recently recognized as pollutants and often lack regulatory limits for their use and discharge. Wastewater treatment plant (WWTP) effluent is a major source of various contaminants of concern, particularly pharmaceutical and personal care products (PPCPs) that are not fully removed during treatment. PPCPs exist at low concentrations in the environment and may have unknown and subtle effects on marine life. Data gaps …


Hemithioindigo-Based Photoswitchable Self- Complementary Hydrogen Bond Arrays, Suendues Noori Dec 2020

Hemithioindigo-Based Photoswitchable Self- Complementary Hydrogen Bond Arrays, Suendues Noori

Electronic Thesis and Dissertation Repository

Hydrogen bonded materials are slowly conquering grounds in the literature because of their dynamic features which stem from their reversible interactions. Incorporating the ability for light to chemically modify these interactions provides a unique template for innovative, efficient and self-healing materials. This thesis explores the design, synthesis, and characterization of nine derivatives of a well-known organic compound – hemithioindigo – with dual function; as a photoswitch and a novel self-complementary hydrogen bond array. The supramolecular complexes formed moderate to strong associations (63 M-1 to 1100 M-1) with spontaneous Gibbs free energy values (-10.3 kJ/mol to -17.3 kJ/mol) …


Automatically Classifying Non-Functional Requirements With Feature Extraction And Supervised Machine Learning Techniques, Mahtab Ezzatikarami Dec 2020

Automatically Classifying Non-Functional Requirements With Feature Extraction And Supervised Machine Learning Techniques, Mahtab Ezzatikarami

Electronic Thesis and Dissertation Repository

Abstract. Context and Motivation: Non-functional requirements (NFRs) of a system need to be classified into different types such as usability, performance, etc. This would enable stakeholders to ensure the completeness of their work by extracting specific NFRs related to their expertise. Question/Problem: Because of the size and complexity of requirement specification documents, the manual classification of NFRs is time-consuming, labour-intensive, and error-prone. We thus need an automated solution that can provide a highly accurate and efficient categorization of NFRs. Principal ideas/results: In this investigation, using natural language processing and supervised machine learning (SML) techniques, we investigate with feature extraction techniques …


The Effect Of The Initial Structure On The System Relaxation Time In Langevin Dynamics, Omid Mozafar Dec 2020

The Effect Of The Initial Structure On The System Relaxation Time In Langevin Dynamics, Omid Mozafar

Electronic Thesis and Dissertation Repository

In recent decades, computer experiments have allowed an accurate and fundamental understanding of molecular mechanisms at the microscopic level, such as the process of relaxation at a stable physical state. However, computer simulations may sometimes produce non-physical results or relations due to the incompleteness of mathematical models describing physical systems. In this thesis, we have investigated whether the initial structure in a computer simulation affects the system relaxation time, which is denoted by τsys, in the Langevin NVT ensemble. We found that for an initial structure, which is inhomogeneous in the number density of atoms, the system relaxation …


Influence Of Some Climatic Elements On Radon Concentration In Saeva Dupka Cave, Bulgaria, Peter Nojarov, Petar Stefanov, Karel Turek Dec 2020

Influence Of Some Climatic Elements On Radon Concentration In Saeva Dupka Cave, Bulgaria, Peter Nojarov, Petar Stefanov, Karel Turek

International Journal of Speleology

This study reveals the influence of some climatic elements on radon concentration in Saeva Dupka Cave, Bulgaria. The research is based mainly on statistical methods. Radon concentration in the cave is determined by two main mechanisms. The first one is through penetration of radon from soil and rocks around the cave (present all year round, but has leading role during the warm half of the year). The second one is through thermodynamic exchange of air between inside of the cave and outside atmosphere (cold half of the year). Climatic factors that affect radon concentration in the cave are temperatures (air, …


Methodological Aspects Of Distance Learning For Developing The Professional Competence Of Students Of The Direction "Computer Engineering, B Kuznetsova, Gulnora Muxtarova, Umida Azimova, Kim Yelena Dec 2020

Methodological Aspects Of Distance Learning For Developing The Professional Competence Of Students Of The Direction "Computer Engineering, B Kuznetsova, Gulnora Muxtarova, Umida Azimova, Kim Yelena

Bulletin of TUIT: Management and Communication Technologies

This work is based on the use of distance learning technologies in education, which will make it possible to individualize training, and in turn contributes to the formation of professionally important qualities for students of the direction of "Computer Engineering". The experimental work was aimed at developing a technology for the formation of students' professional competence.

The article shows that the mastery by students of knowledge, skills and abilities in the field of computer engineering was aimed at their conscious application in solving problems of the educational and cognitive process, and subsequently in professional activity.

The article presents the results …


2. Modeling, Zhiqu Lu, Likun Zhang, Lei Cao Dec 2020

2. Modeling, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

This data set contains the results for acoustic bubble modeling.


3. Localization, Zhiqu Lu, Likun Zhang, Lei Cao Dec 2020

3. Localization, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

This data set contains the results for oil leakage source localization.


6. Supplemental Materials, Zhiqu Lu, Likun Zhang, Lei Cao Dec 2020

6. Supplemental Materials, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

This data set contains all conference presentations, manuscripts, technical reports, posters.


Toward Non-Invasive Measurement Of Atmospheric Temperature Using Vibro-Rotational Raman Spectra Of Diatomic Gases, Tyler Capek, Jacek Borysow, Claudio Mazzoleni, Massimo Moraldi Dec 2020

Toward Non-Invasive Measurement Of Atmospheric Temperature Using Vibro-Rotational Raman Spectra Of Diatomic Gases, Tyler Capek, Jacek Borysow, Claudio Mazzoleni, Massimo Moraldi

Michigan Tech Publications

We demonstrate precise determination of atmospheric temperature using vibro-rotational Raman (VRR) spectra of molecular nitrogen and oxygen in the range of 292–293 K. We used a continuous wave fiber laser operating at 10 W near 532 nm as an excitation source in conjunction with a multi-pass cell. First, we show that the approximation that nitrogen and oxygen molecules behave like rigid rotors leads to erroneous derivations of temperature values from VRR spectra. Then, we account for molecular non-rigidity and compare four different methods for the determination of air temperature. Each method requires no temperature calibration. The first method involves fitting …


Factors Impacting Students’ Perceptions Of Mathematics, Amber Souza Dec 2020

Factors Impacting Students’ Perceptions Of Mathematics, Amber Souza

Honors Program Theses and Projects

I want to be able to present math in a positive light to all of my future students, regardless of race, gender, and math background. However, for teachers as a whole to be able to take this important step, they must first develop a deeper understanding of why math is a sore spot for many students.


Short And Long Term Effects Of Lime And Gypsum Applications On Acid Soils In A Water-Limited Environment: 2. Soil Chemical Properties, Geoff Anderson, Shahab Pathan, James Easton, David Hall, Rajesh Sharma Dec 2020

Short And Long Term Effects Of Lime And Gypsum Applications On Acid Soils In A Water-Limited Environment: 2. Soil Chemical Properties, Geoff Anderson, Shahab Pathan, James Easton, David Hall, Rajesh Sharma

Grain and Other Field Crops Research Articles

Soil acidity or aluminum (Al) toxicity is a major limitation to crop production. In this paper, we examine the effects of surface-applied lime and gypsum on soil profile chemical properties that affect Al toxicity in short-term (1 year), medium-term (2 years and 8 months) and long-term (10 years) experiments. Sulfate applied to the soil surface as gypsum was leached rapidly to a depth of 40 cm in the short-term despite relatively low amounts (279 mm) of rainfall. In the medium and long-term experiments, 28–54% of the sulfate applied as gypsum was retained in the 0–50 cm soil layer due to …


A Preliminary Analysis Of How A Software Organization’S Maturity And Size Affect Its Intellectual Property Portfolio, Daniel Gifford Dec 2020

A Preliminary Analysis Of How A Software Organization’S Maturity And Size Affect Its Intellectual Property Portfolio, Daniel Gifford

Master of Science in Software Engineering Theses

Intellectual property, commonly known as IP, is complex. The four main types of software IP, which is what this thesis will focus on, are patents, trade secrets, trademarks, and copyright. Patents, trade secrets, and copyrights were all studied by this thesis. Software IP is unique in that it can by copyrighted. Different IP owners, which can be businesses of different types, individuals, and universities, often have different strategies as to how to use their IP portfolio. This thesis studies differences in IP usage between these entities specifically in the field of software. Large and small software companies were analyzed specifically. …


Malware Classification Using Lstms, Dennis Dang Dec 2020

Malware Classification Using Lstms, Dennis Dang

Master's Projects

Signature and anomaly based detection have long been quintessential techniques used in malware detection. However, these techniques have become increasingly ineffective as malware becomes more complex. Researchers have therefore turned to deep learning to construct better performing models. In this project, we create four different long-short term memory (LSTM) models and train each model to classify malware by family type. Our data consists of opcodes extracted from malware executables. We employ techniques used in natural language processing (NLP) such as word embedding and bidirection LSTMs (biLSTM). We also use convolutional neural networks (CNN). We found that our model consisting of …


5. Programs And Algorithms, Zhiqu Lu, Likun Zhang, Lei Cao Dec 2020

5. Programs And Algorithms, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

This data set contains all codes for the study.


4. Metadata Files, Zhiqu Lu, Likun Zhang, Lei Cao Dec 2020

4. Metadata Files, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

This data set contains all ReadMe files for test data, modeling data, and localization data, as well as the corresponding codes.


1. Test Data, Zhiqu Lu, Likun Zhang, Lei Cao Dec 2020

1. Test Data, Zhiqu Lu, Likun Zhang, Lei Cao

Gulf Research Program Data Sets

This data set contains recorded and processed bubble sounds under different conditions: a few bubbles vs. constant flow bubbles. Each condition is tested with nitrogen and with methane.


Quantifying Deepfake Detection Accuracy For A Variety Of Natural Settings, Pratikkumar Prajapati Dec 2020

Quantifying Deepfake Detection Accuracy For A Variety Of Natural Settings, Pratikkumar Prajapati

Master's Projects

Deep fakes are videos generated from a starting video of a person where that person's face has been swapped for someone else's. In this report, we describe our work to develop general, deep learning-based models to classify Deep Fake content. Our first experiments involved simple Convolution Neural Network (CNN)-based models where we varied how individual frames from the source video were passed to the CNN. These simple models tended to give low accuracy scores for discriminating fake versus non-fake videos of less than 60%. We then developed three more sophisticated models: one based on choosing test frames, one based on …


Bioinformatics Metadata Extraction For Machine Learning Analysis, Zachary Tom Dec 2020

Bioinformatics Metadata Extraction For Machine Learning Analysis, Zachary Tom

Master's Projects

Next generation sequencing (NGS) has revolutionized the biological sciences. Today, entire genomes can be rapidly sequenced, enabling advancements in personalized medicine, genetic diseases, and more. The National Center for Biotechnology Information (NCBI) hosts the Sequence Read Archive (SRA) containing vast amounts of valuable NGS data. Recently, research has shown that sequencing errors in conventional NGS workflows are key confounding factors for detecting mutations. Various steps such as sample handling and library preparation can introduce artifacts that affect the accuracy of calling rare mutations. Thus, there is a need for more insight into the exact relationship between various steps of the …


The Evaluation Of Two Cultivation Methods To Over‐Sow Perennial Clovers Into Kikuyu, Philip R. Botha, Robin Meeske, Hennie A. Snyman Dec 2020

The Evaluation Of Two Cultivation Methods To Over‐Sow Perennial Clovers Into Kikuyu, Philip R. Botha, Robin Meeske, Hennie A. Snyman

IGC Proceedings (1993-2023)

No abstract provided.


Temporal Mobility Patterns Of Livestock In Semi‐Arid Communal Rangelands In South Africa, Igshaan Samuels, Nicky Allsopp, Timm Hoffman Dec 2020

Temporal Mobility Patterns Of Livestock In Semi‐Arid Communal Rangelands In South Africa, Igshaan Samuels, Nicky Allsopp, Timm Hoffman

IGC Proceedings (1993-2023)

No abstract provided.


Energetic Supplementation For Beef Heifers Grazing Temperate Pasture, Marta G. Da Rocha, L. Potter Dec 2020

Energetic Supplementation For Beef Heifers Grazing Temperate Pasture, Marta G. Da Rocha, L. Potter

IGC Proceedings (1993-2023)

No abstract provided.


One-Pot Synthesis Of Bicyclic Piperidines From Donor Acceptor Cyclopropanes, David G. Stephens Dec 2020

One-Pot Synthesis Of Bicyclic Piperidines From Donor Acceptor Cyclopropanes, David G. Stephens

Electronic Thesis and Dissertation Repository

The efficient synthesis of heterocyclic compounds is of great importance to organic chemistry. One method for achieving efficiency is through the use and development of one-pot reactions. This thesis describes the planning and development of an extension to the tandem cyclopropane opening Conia-ene reactivity previously reported. A search for a substrate capable of undergoing the reaction was undertaken and the reaction was optimized. The highest yielding conditions tested used catalytic Sc(OTf)3 and superstoichiometric ZnBr2, but other catalyst systems also worked. The optimized reaction conditions tolerated 6-membered rings well in addition to 7-membered rings in some rotationally restricted …


Regional Integration: Physician Perceptions On Electronic Medical Record Use And Impact In South West Ontario, Sadiq Raji Dec 2020

Regional Integration: Physician Perceptions On Electronic Medical Record Use And Impact In South West Ontario, Sadiq Raji

Electronic Thesis and Dissertation Repository

Regional initiatives in the health care context in Canada are typically organized and administered along geographic boundaries or operational units. Regional integration of Electronic Medical Records (EMR) has been continuing across Canadian provinces in recent years, yet the use and impact of regionally integrated EMRs are not routinely assessed and questions remain about their impact on and use in physicians’ practices. Are stated goals of simplifying connections and sharing of electronic health information collected and managed by many health services providers being met? What are physicians’ perspectives on the use and impact of regionally integrated EMR? In this thesis, I …


Applying Front End Compiler Process To Parse Polynomials In Parallel, Amha W. Tsegaye Dec 2020

Applying Front End Compiler Process To Parse Polynomials In Parallel, Amha W. Tsegaye

Electronic Thesis and Dissertation Repository

Parsing large expressions, in particular large polynomial expressions, is an important task for computer algebra systems. Despite of the apparent simplicity of the problem, its efficient software implementation brings various challenges. Among them is the fact that this is a memory bound application for which a multi-threaded implementation is necessarily limited by the characteristics of the memory organization of supporting hardware.

In this thesis, we design, implement and experiment with a multi-threaded parser for large polynomial expressions. We extract parallelism by splitting the input character string, into meaningful sub-strings that can be parsed concurrently before being merged into a single …


Annual Legumes With Greater Water Use Efficiency Can Overcome Seasonal Feed Imbalance, Belinda Hackney, B. Dear, G. Dyce, C. Rodham, G. Li Dec 2020

Annual Legumes With Greater Water Use Efficiency Can Overcome Seasonal Feed Imbalance, Belinda Hackney, B. Dear, G. Dyce, C. Rodham, G. Li

IGC Proceedings (1993-2023)

No abstract provided.


Productive And Sustainable Pasture Systems: Responding To Climate Variability In The South West Of Australia, Ned Crossley Dec 2020

Productive And Sustainable Pasture Systems: Responding To Climate Variability In The South West Of Australia, Ned Crossley

IGC Proceedings (1993-2023)

No abstract provided.


Performance Of Beef Cattle Females Grazing Under Different Feeding Systems Based On Native Pastures In Southern Brazil, Carlos Nabinger, Teresa C. M. Genro, F. F. Cardoso, M. G. Orqis, M. M. Oliveira, D. P. Montardo Dec 2020

Performance Of Beef Cattle Females Grazing Under Different Feeding Systems Based On Native Pastures In Southern Brazil, Carlos Nabinger, Teresa C. M. Genro, F. F. Cardoso, M. G. Orqis, M. M. Oliveira, D. P. Montardo

IGC Proceedings (1993-2023)

No abstract provided.


Non-Cooperative Target Feature Point Cloud Registration Optimization Based On Icp Algorithm, Wei Liang, Muyao Xue, Huo Ju, Jinjie Zhang Dec 2020

Non-Cooperative Target Feature Point Cloud Registration Optimization Based On Icp Algorithm, Wei Liang, Muyao Xue, Huo Ju, Jinjie Zhang

Journal of System Simulation

Abstract: Aiming at the pose measurement caused by non-cooperative targets in visual measurement that cannot provide cooperation information,the ICP(Iterative Closest Point) algorithm is used to register the point cloud down-sampling data acquired at different times to complete the relative pose measurement of the target.The point cloud data of the target at the current moment is obtained using the structure from motion algorithm and the feature point matching algorithms are compared based on threshold matching and optical flow matching method.The extracted feature points are reconstructed by triangulation.The relative pose changes of the object at different times are calculated by using …


Applying The Food-Energy-Water Nexus Approach To Urban Agriculture: From Few To Fewp (Food-Energy- Water-People), Silvio Caputo, Victoria Schoen, Kathrin Spect, Baptiste Grard, Chris Blythe, Nevin Cohen, Runrid Fox-Kämper, Jason Hawes, Joshua Newell, Lidia Poniży Dec 2020

Applying The Food-Energy-Water Nexus Approach To Urban Agriculture: From Few To Fewp (Food-Energy- Water-People), Silvio Caputo, Victoria Schoen, Kathrin Spect, Baptiste Grard, Chris Blythe, Nevin Cohen, Runrid Fox-Kämper, Jason Hawes, Joshua Newell, Lidia Poniży

Publications and Research

Many studies examine the correlation between the use of resources such as water, energy and land, and the production of food. These nexus studies focus predominantly on large scale systems, often considering the social dimensions only in terms of access to resources and participation in the decision- making process, rather than individual attitudes and behaviours with respect to resource use. Such a concept of the nexus is relevant to urban agriculture (UA), but it requires customisation to the particular characteristics of growing food in cities, which is practiced mainly at a small scale and produces not only food but also …