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Florida International University

2021

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Articles 31 - 45 of 45

Full-Text Articles in Physical Sciences and Mathematics

Reimagining The Archive For Computational Analysis At Scale, Jamie Rogers Jun 2021

Reimagining The Archive For Computational Analysis At Scale, Jamie Rogers

Works of the FIU Libraries

This presentation was part of a three-segment panel discussion sponsored by IS&T, the Society for Imaging Science and Technology, titled "OCR and Text Recognition: Workflows, Trends, and New Applications." This segment covers ways in which we have re-conceptualized archive materials as computationally useful data as well as the value of utilizing data at scale to impact research possibilities. We have been able to accomplish this through an ongoing project "dLOC as Data: A Thematic Approach to Caribbean Newspapers," a collaborative initiative between the Digital Library of the Caribbean, University of Florida, and Florida International University.


Structural Dynamics Of Membrane Interacting Viral Proteins, Nisha Bhattarai May 2021

Structural Dynamics Of Membrane Interacting Viral Proteins, Nisha Bhattarai

FIU Electronic Theses and Dissertations

Viruses do not possess complete cellular machinery but have the ability to reproduce by utilizing cellular machinery inside host cells. They are nanoscale machines that rapidly modify (evolve) their molecular components to cause disease and death. Therefore, emergence of deadly infectious viruses is a monumental health concern and understanding how viruses are able to enter, replicate, assemble and egress from the host cell is important to mitigate the threat.

A fully active, infectious viral structure is known as a virion. A virion contains genetic material and is enclosed by a capsid. The capsid is a protein shell and some viruses …


Technical Interviews: Another Barrier To Broadening Participation In Computing?, Stephanie Jill Lunn May 2021

Technical Interviews: Another Barrier To Broadening Participation In Computing?, Stephanie Jill Lunn

FIU Electronic Theses and Dissertations

What does it take to obtain a computing position in the industry? Although anecdotal reports state that ``hiring is broken,'' empirical evidence is necessary to identify the flaws in the existing system. The goal of this dissertation was to understand what expectations companies have for job seekers in computing, and to explore students' experiences with technical interviews and their pathways to job attainment. In particular, this work considered how hiring practices may impact populations already underrepresented in computing such as women, Black/African American students, and Hispanic/Latinx students. It also sought to understand how minoritized populations leverage their own inherent capital …


Exercise, Cognition, And Cannabis Use In Adolescents, Ileana Pacheco-Colón May 2021

Exercise, Cognition, And Cannabis Use In Adolescents, Ileana Pacheco-Colón

FIU Electronic Theses and Dissertations

Heavy and/or chronic cannabis use has been associated with neurocognitive impairment and decline, often in domains such as memory and executive functioning. On the other hand, exercise has been linked to positive effects on brain and cognitive health across the lifespan, as well as to better substance use outcomes. Despite this, little is known about the ways in which exercise could help prevent or ameliorate adverse cannabis-related outcomes among adolescents.

Through three separate studies, the current dissertation examines interrelations among exercise, cognition, and cannabis use in children and adolescents in an effort to determine whether exercise can prevent or ameliorate …


Utilizing Headspace Solid-Phase Microextraction For The Characterization Of Volatile Organic Compounds Released From Contraband And Its Implications For Detector Dog Training, Kelvin Joseph Frank Jr Apr 2021

Utilizing Headspace Solid-Phase Microextraction For The Characterization Of Volatile Organic Compounds Released From Contraband And Its Implications For Detector Dog Training, Kelvin Joseph Frank Jr

FIU Electronic Theses and Dissertations

Improving the accuracy and reliability of odor detection dogs is of utmost importance particularly for legal reasons. Field testing in conjunction with headspace analysis of volatile organic compounds (VOCs) has in recent times allowed for these improvements, by providing scientifically based recommendations for optimum training protocols. The current project leveraged on these established capabilities to enhance three areas of odor detection: illicit drugs, explosives and mass storage devices.

With hemp being legalized under the 2018 Farm Bill, legal questions have been raised regarding a dog’s ability to ignore hemp if trained to detect marijuana, as both are types of Cannabis …


Collections As Data At Florida International University, Jamie Rogers Apr 2021

Collections As Data At Florida International University, Jamie Rogers

Works of the FIU Libraries

This presentation provides an overview of the concept of collections as data; shares information about our "dLOC as Data" grant initiative, a collaboration between the Digital Library of the Caribbean (dLOC), the Florida International University (FIU) Libraries Digital Collections Center, and the University of Florida Libraries, funded by the Mellon sub-award program, "Collections as Data: Part to Whole" ; as well as provides an opportunity to talk about how we can share more collections as data resources and undertake new and exciting projects at FIU.

Although the concept of collections as data isn't new, it is becoming more mainstream. As …


Development Of A Real-Time Single-Lead Single-Beat Frequency-Independent Myocardial Infarction Detector, Harold Martin Mar 2021

Development Of A Real-Time Single-Lead Single-Beat Frequency-Independent Myocardial Infarction Detector, Harold Martin

FIU Electronic Theses and Dissertations

The central aim of this research is the development and deployment of a novel multilayer machine learning design with unique application for the diagnosis of myocardial infarctions (MIs) from individual heartbeats of single-lead electrocardiograms (EKGs) irrespective of their sampling frequencies over a given range. To the best of our knowledge, this design is the first to attempt inter-patient myocardial infarction detection from individual heartbeats of single-lead (lead II) electrocardiograms that achieves high accuracy and near real-time diagnosis. The processing time of 300 milliseconds to a diagnosis is just at the time range in between extremely fast heartbeats of around 300 …


Evaluation Of Harvesting Time For Industrial Hemp (Cannabis Sativa L,) Pilot Project Varieties Grown In South Florida, Jordan W. Prats Mar 2021

Evaluation Of Harvesting Time For Industrial Hemp (Cannabis Sativa L,) Pilot Project Varieties Grown In South Florida, Jordan W. Prats

FIU Electronic Theses and Dissertations

A field study was conducted to observe the natural development of cannabinoids in three daylength sensitive industrial hemp varieties Bubba Kush (BK), Emerald Flower (EF), and Golden Sunset (GS). Plants were configured in a randomized block design with 3 replications. Once 50% of the plants within a variety reached reproductive growth, plants were sampled weekly until senescence and analyzed through a HPLC-UV/DAD. The results from the study indicate that all three varieties of industrial hemp tested in field study reached reproductive growth within the first week of transplanting. This is due to a 12-hour day-length at the time and the …


Competitive Reductive Removal Of Chromate And Pertechnetate Via Zero-Valent Iron, Jonathan Williams Ramirez Mar 2021

Competitive Reductive Removal Of Chromate And Pertechnetate Via Zero-Valent Iron, Jonathan Williams Ramirez

FIU Electronic Theses and Dissertations

Treatment to immobilize radioactive waste is of concern for long-term storage, avoiding future environmental exposure. Most production of Technetium-99 (99Tc) occurred as a byproduct of development of legacy nuclear weapons research. Zero-valent iron (ZVI) is a promising reductant of Tc(VII) to a less mobile 99Tc(IV). However, more redox-sensitive contaminants can compete in the reductive process. Therefore, it is important to examine the effects of competitive contaminants and quantify the effects on the reductive removal rates of 99Tc. Chromate, Cr(VI), is a redox-sensitive contaminant that is expected to be present in legacy waste present in the Hanford …


Electron Field Emission And Electrochemical Lithiation Properties Of Vertically Aligned Carbon Nanotube Arrays Grown Directly On Metal Substrates, Arun Thapa Mar 2021

Electron Field Emission And Electrochemical Lithiation Properties Of Vertically Aligned Carbon Nanotube Arrays Grown Directly On Metal Substrates, Arun Thapa

FIU Electronic Theses and Dissertations

Carbon nanotubes (CNTs) represent one of the critical inventions that have triggered new science and technology in many fields because of their distinctive mechanical, thermal, electrical, electrochemical, and optical properties. Despite the tremendous potential of CNTs, challenges in synthesizing and processing continue to hinder their applications. This dissertation is devoted to synthesizing vertically aligned CNT arrays on metal substrates via plasma-enhanced chemical vapor deposition and the study of their electron field emission (FE) and electrochemical lithiation properties.

Vertically aligned CNTs (VACNTs) are promising electron field emitters for vacuum micro/nano-electronics. Improved control over the morphology and a successful direct-growth of the …


Evaluation Of Parametric And Nonparametric Statistical Models In Wrong-Way Driving Crash Severity Prediction, Sajidur Rahman Nafis Mar 2021

Evaluation Of Parametric And Nonparametric Statistical Models In Wrong-Way Driving Crash Severity Prediction, Sajidur Rahman Nafis

FIU Electronic Theses and Dissertations

Wrong-way driving (WWD) crashes result in more fatalities per crash, involve more vehicles, and cause extended road closures compared to other types of crashes. Although crashes involving wrong-way drivers are relatively few, they often lead to fatalities and serious injuries. Researchers have been using parametric statistical models to identify factors that affect WWD crash severity. However, these parametric models are generally based on several assumptions, and the results could generate numerous errors and become questionable when these assumptions are violated. On the other hand, nonparametric methods such as data mining or machine learning techniques do not use a predetermined functional …


Uranium Fate And Mineral Transformations Upon Remediation With Ammonia (Nh3) Gas, Silvina A. Di Pietro Mar 2021

Uranium Fate And Mineral Transformations Upon Remediation With Ammonia (Nh3) Gas, Silvina A. Di Pietro

FIU Electronic Theses and Dissertations

The fission of uranium (U) for plutonium production was a major activity at the U.S. Department of Energy’s (DOE) Hanford Site in Washington State during World War II and Cold War. This endeavor resulted in the generation of over two million liters of high-level radioactive waste, most of which still remains in 177 underground storage tanks. Due to the improper storage and aging of these tanks in addition to other waste releases across the Site, approximately 200,000 kg of U have been released into the vadose zone. The objective of this study was to determine whether the application of the …


Comparison Of Modern And Mid-Holocene Benthic Foraminifera To Assess Recent Environmental Change In Almirante Bay, Caribbean Panama, Maria N. Gudnitz Mar 2021

Comparison Of Modern And Mid-Holocene Benthic Foraminifera To Assess Recent Environmental Change In Almirante Bay, Caribbean Panama, Maria N. Gudnitz

FIU Electronic Theses and Dissertations

This study used the diversity and distribution of benthic foraminiferal assemblages of Almirante Bay, Caribbean Panama, as environmental proxies to compare modern coral, seagrass and mangrove habitats to mid-Holocene coral reef facies on the island of Isla Colón, to investigate both natural and human-influenced changes.

The modern study associated species and assemblage characteristics with environmental conditions related to degraded water quality. Assemblages were fairly similar among neighboring habitats but differed in species proportions, while several stress-tolerant taxa might indicate eutrophic conditions. Diversity appeared to be regionally controlled by freshwater input irrespective of habitat type, was generally lower near the mainland …


Correlating Water Quality And Profile Data In The Florida Keys Using Machine Learning Methods, Alejandro M. Torres Castellanos Mar 2021

Correlating Water Quality And Profile Data In The Florida Keys Using Machine Learning Methods, Alejandro M. Torres Castellanos

FIU Electronic Theses and Dissertations

Water quality is a very active subject of research in the water science field, where its importance includes maintaining the environment, managing wastewater, and securing fresh water. However, the increase of human development has led to problems that are affecting the ecosystem. Motivated by these problems, this research aims to find a solution for understanding the coastal water of the Florida Keys. The research used machine learning methods to find a correlation between water quality dataset and profile measurements dataset. To achieve this objective, the research first went through cleaning, rescuing, and structuring a readable dataset of the profile measurements …


An Angle-Based Stochastic Gradient Descent Method For Machine Learning: Principle And Application, Chongya Song Feb 2021

An Angle-Based Stochastic Gradient Descent Method For Machine Learning: Principle And Application, Chongya Song

FIU Electronic Theses and Dissertations

In deep learning, optimization algorithms are employed to expedite the resolution to accurate models through the calibrations of the current gradient and the associated learning rate. A major shortcoming of these existing methods is the manner in which the calibration terms are computed, only utilizing the previous gradients during their computations. Because the gradient is a time-sensitive variable computed at a specific moment in time, it is possible that older gradients can introduce significant deviation into the calibration terms. Although most algorithms alleviate this situation by combining the exponential moving average of the previous gradients, we found that this method …