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Full-Text Articles in Physical Sciences and Mathematics

Traditional Vs Machine Learning Approaches: A Comparison Of Time Series Modeling Methods, Miguel E. Bonilla Jr., Jason Mcdonald, Tamas Toth, Bivin Sadler Aug 2023

Traditional Vs Machine Learning Approaches: A Comparison Of Time Series Modeling Methods, Miguel E. Bonilla Jr., Jason Mcdonald, Tamas Toth, Bivin Sadler

SMU Data Science Review

In recent years, various new Machine Learning and Deep Learning algorithms have been introduced, claiming to offer better performance than traditional statistical approaches when forecasting time series. Studies seeking evidence to support the usage of ML/DL over statistical approaches have been limited to comparing the forecasting performance of univariate, linear time series data. This research compares the performance of traditional statistical-based and ML/DL methods for forecasting multivariate and nonlinear time series.


A Hybrid Ensemble Of Learning Models, Bivin Sadler, Dhruba Dey, Duy Nguyen, Tavin Weeda Aug 2023

A Hybrid Ensemble Of Learning Models, Bivin Sadler, Dhruba Dey, Duy Nguyen, Tavin Weeda

SMU Data Science Review

Statistical models in time series forecasting have long been challenged to be superseded by the advent of deep learning models. This research proposes a new hybrid ensemble of forecasting models that combines the strengths of several strong candidates from these two model types. The proposed ensemble aims to improve the accuracy of forecasts and reduce computational complexity by leveraging the strengths of each candidate model.


Functional Connectivity Varies Across Scales In A Fragmented Landscape, Kate I. T. Bird, Daniel R. Uden, Craig R. Allen Aug 2023

Functional Connectivity Varies Across Scales In A Fragmented Landscape, Kate I. T. Bird, Daniel R. Uden, Craig R. Allen

School of Natural Resources: Faculty Publications

Species of different sizes interact with the landscape differently because ecological structure varies with scale, as do species movement capabilities and habitat requirements. As such, landscape connectivity is dependent upon the scale at which an animal interacts with its environment. Analyses of landscape connectivity must incorporate ecologically relevant scales to address scale-specific differences. Many evaluations of landscape connectivity utilize incrementally increasing buffer distances or other arbitrary spatial delineations as scales of analysis. Instead, we used a mammalian body mass discontinuity analysis to objectively identify scales in the Central Platte River Valley (CPRV) of Nebraska, U.S.A. We implemented a graph-theoretic network …


Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites – Field Sampling Plan (Fsp) Bres No. 84 – Mandan Park Play Area, Mike Mcanulty Aug 2023

Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites – Field Sampling Plan (Fsp) Bres No. 84 – Mandan Park Play Area, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Machine Learning Techniques To Predict The Air Quality Using Meteorological Data In Two Urban Areas In Sri Lanka, Lakindu Mampitiya, Namal Rathnayake, Lee P. Leon, Vishwanadham Mandala, Hazi Md. Azamathulla, Sherly Shelton, Yukinobu Hoshino, Upaka Rathnayake Aug 2023

Machine Learning Techniques To Predict The Air Quality Using Meteorological Data In Two Urban Areas In Sri Lanka, Lakindu Mampitiya, Namal Rathnayake, Lee P. Leon, Vishwanadham Mandala, Hazi Md. Azamathulla, Sherly Shelton, Yukinobu Hoshino, Upaka Rathnayake

Department of Earth and Atmospheric Sciences: Faculty Publications

The effect of bad air quality on human health is a well-known risk. Annual health costs have significantly been increased in many countries due to adverse air quality. Therefore, forecasting air quality-measuring parameters in highly impacted areas is essential to enhance the quality of life. Though this forecasting is usual in many countries, Sri Lanka is far behind the state-of-the-art. The country has increasingly reported adverse air quality levels with ongoing industrialization in urban areas. Therefore, this research study, for the first time, mainly focuses on forecasting the PM10 values of the air quality for the two urbanized areas …


Secondary Features Of Importance For A Url Ranking, Atajan Abdyyev Aug 2023

Secondary Features Of Importance For A Url Ranking, Atajan Abdyyev

Dissertations and Theses

This paper investigates the impact of secondary ranking factors on webpage relevance and rankings in the context of Search Engine Optimization (SEO), focusing on the jewelry domain within the United States e-commerce market. By generating a keyword list related to jewelry and retrieving top URLs from Google's search results, the study employs machine learning models including XGBoost, CatBoost, and Linear Regression to identify key features influencing webpage relevance and rankings.The findings highlight specific optimal ranges for features like Outlinks, Unique Inlinks, Flesch Reading Ease Score, and others, indicating their significant impact on better rankings. Notably, Random Forest model performed best …


A Critical Inter-Subunit Interaction For The Transmission Of The Allosteric Signal In The Agrobacterium Tumefaciens Adp-Glucose Pyrophosphorylase, Hiral Patel, Gabriela Martinez-Ramirez Ms., Emily Dobrzynski, Alberto A. Iglesias, Dali Liu, Miguel Ballicora Aug 2023

A Critical Inter-Subunit Interaction For The Transmission Of The Allosteric Signal In The Agrobacterium Tumefaciens Adp-Glucose Pyrophosphorylase, Hiral Patel, Gabriela Martinez-Ramirez Ms., Emily Dobrzynski, Alberto A. Iglesias, Dali Liu, Miguel Ballicora

Chemistry: Faculty Publications and Other Works

ADP-glucose pyrophosphorylase is a key regulatory enzyme involved in starch and glycogen synthesis in plants and bacteria, respectively. It has been hypothesized that inter-subunit communications are important for the allosteric effect in this enzyme. However, no specific interactions have been identified as part of the regulatory signal. The enzyme from Agrobacterium tumefaciens is a homotetramer allosterically regulated by fructose 6-phosphate and pyruvate. Three pairs of distinct subunit-subunit interfaces are present. Here we focus on an interface that features two symmetrical interactions between Arg11 and Asp141 from one subunit with residues Asp141 and Arg11 of the neighbor subunit, respectively. Previously, scanning …


Supporting The “Virtuous Cycle” In Urban Ecosystems: How Research Can Inform Plans, Policies, And Projects That Impact Urban Resilience, Michele Romilini, Sophie S. Parker, Gregory B. Pauly, Eric M. Wood Aug 2023

Supporting The “Virtuous Cycle” In Urban Ecosystems: How Research Can Inform Plans, Policies, And Projects That Impact Urban Resilience, Michele Romilini, Sophie S. Parker, Gregory B. Pauly, Eric M. Wood

Center for Urban Resilience Scholarship

No abstract provided.


Final Approved Request For Change Bg-2023-01 To Final Bpsou Hydrocarbon Sampling And Treatability Study Quality Assurance Project Plan (Qapp), Josh Bryson Aug 2023

Final Approved Request For Change Bg-2023-01 To Final Bpsou Hydrocarbon Sampling And Treatability Study Quality Assurance Project Plan (Qapp), Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Crop Monitoring And Nutrient Prediction Using Satellite Imagery And Soil Data, Olatunde D. Akanbi, Brian Gonzalez Hernandez, Erika I. Barcelos, Arafath Nihar, Laura S. Bruckman, Yinghui Wu, Jeffrey Yarus, Roger H. French Aug 2023

Crop Monitoring And Nutrient Prediction Using Satellite Imagery And Soil Data, Olatunde D. Akanbi, Brian Gonzalez Hernandez, Erika I. Barcelos, Arafath Nihar, Laura S. Bruckman, Yinghui Wu, Jeffrey Yarus, Roger H. French

Student Scholarship

No abstract provided.


Draft Final 2023 Residential Metals Abatement Program (Rmap) Gold Hill Lutheran Church (Containing The Creativity Factory Preschool) Soil Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc. Aug 2023

Draft Final 2023 Residential Metals Abatement Program (Rmap) Gold Hill Lutheran Church (Containing The Creativity Factory Preschool) Soil Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Vertical Federated Learning Using Autoencoders With Applications In Electrocardiograms, Wesley William Chorney Aug 2023

Vertical Federated Learning Using Autoencoders With Applications In Electrocardiograms, Wesley William Chorney

Theses and Dissertations

Federated learning is a framework in machine learning that allows for training a model while maintaining data privacy. Moreover, it allows clients with their own data to collaborate in order to build a stronger, shared model. Federated learning is of particular interest to healthcare data, since it is of the utmost importance to respect patient privacy while still building useful diagnostic tools. However, healthcare data can be complicated — data format might differ across providers, leading to unexpected inputs and incompatibility between different providers. For example, electrocardiograms might differ in sampling rate or number of leads used, meaning that a …


Signings Of Graphs And Sign-Symmetric Signed Graphs, Ahmad Asiri Aug 2023

Signings Of Graphs And Sign-Symmetric Signed Graphs, Ahmad Asiri

Theses and Dissertations

In this dissertation, we investigate various aspects of signed graphs, with a particular focus on signings and sign-symmetric signed graphs. We begin by examining the complete graph on six vertices with one edge deleted ($K_6$\textbackslash e) and explore the different ways of signing this graph up to switching isomorphism. We determine the frustration index (number) of these signings and investigate the existence of sign-symmetric signed graphs. We then extend our study to the $K_6$\textbackslash 2e graph and the McGee graph with exactly two negative edges. We investigate the distinct ways of signing these graphs up to switching isomorphism and demonstrate …


Synthesis And Characterization Of Redox-Noninnocent Pyrazine(Diimine) Iron Complexes And An Inverted Pyridine(Diimine) Ligand, Jaylan Billups Aug 2023

Synthesis And Characterization Of Redox-Noninnocent Pyrazine(Diimine) Iron Complexes And An Inverted Pyridine(Diimine) Ligand, Jaylan Billups

Theses and Dissertations

Cooperativity between the metal center and the ligand has been shown in nature to be an important feature of systems that catalyze two-electron processes that first-row transition metals usually cannot catalyze on their own. In these cases, the ligand acts as a site of reactivity that in many instances can store electrons or react directly with substrates in solution. The design and study of systems where there is synergy between the metal and the ligand have been leveraged to catalyze polymerization and hydrogenation-type reactions as well as the activation of small molecules such as dihydrogen. Specifically, the pyridine(diimine) ligand scaffold …


Identifying Student Challenges In Organic Chemistry: Supporting Student Understanding Through Eye-Tracking, Think-Aloud Interviews And Alternative Questions, Lisa Ann Smith Aug 2023

Identifying Student Challenges In Organic Chemistry: Supporting Student Understanding Through Eye-Tracking, Think-Aloud Interviews And Alternative Questions, Lisa Ann Smith

Theses and Dissertations

Think-aloud interviews are a strategy used to identify misconceptions held by students. We incorporated think-aloud interviews and studied representational competence of novice and expert participants with identifying alkyl halides with multiple representations. We hypothesized that the participants would approach representations differently and think-aloud interviews would reveal misconceptions. Eye-tracking results showed that novice and expert participants differ in their approaches to representations and that novice participants spend more time on representations. Think-aloud interviews revealed that novice participants contain misconceptions on alkyl halide identification. This research provided insights on student understanding in identifying alkyl halides and representations, allowing instructors to use student …


Transition Metal-Catalyzed Functionalization Of Carbon-Hydrogen Bonds In Alkenes, Xiaolin Qian Aug 2023

Transition Metal-Catalyzed Functionalization Of Carbon-Hydrogen Bonds In Alkenes, Xiaolin Qian

Theses and Dissertations

Alkenes can undergo a variety of chemical reactions to form more complex molecules with a range of functional groups. This makes them useful starting materials for synthesizing a wide range of organic compounds. Chapter I provided an overview of the development history of alkenyl C−H bond activation. The early reactions of C−H compounds with metal complexes, as well as stoichiometric activation of the transition metal-activated C–H bond, were discussed. Then the first successful and efficient organometallic-catalyzed transformations of a C−H bond, the first transition metal-catalyzed vinylic C–H functionalization, and the first transition metal-catalyzed olefinic C–H functionalization under mild conditions were …


Direct Measurement Of The 114cd(N, Gamma)115cd Cross Section In The 1 Ev To 300 Kev Energy Range, Kofi Tutu Addo Assumin-Gyimah Aug 2023

Direct Measurement Of The 114cd(N, Gamma)115cd Cross Section In The 1 Ev To 300 Kev Energy Range, Kofi Tutu Addo Assumin-Gyimah

Theses and Dissertations

The large thermal cross section of cadmium makes it ideal for many practical applications where screening of thermal neutrons is desired. For example, in non-destructive assay techniques, or for astrophysical studies of the s-process. All such applications require precise knowledge of the neutron-capture cross section on cadmium. Although there are some data on neutron-capture cross sections particularly at thermal energies and at energies relevant for astrophysics, there is very little data at most other energies. Further, the evaluated cross sections from the ENDF and JENDL databases disagree at high energies. Therefore, there is a critical need for precise knowledge of …


Changes In Paleobiodiversity Across The K-Pg Boundary In Oktibbeha County, Mississippi, Joshua Broussard Aug 2023

Changes In Paleobiodiversity Across The K-Pg Boundary In Oktibbeha County, Mississippi, Joshua Broussard

Theses and Dissertations

Evidence of the Cretaceous-Paleogene (K-Pg) extinction can be seen across the Mississippi Embayment, however research examining the K-Pg boundary in the state of Mississippi is lacking. The objective of this study addresses how macrofauna changed across the K-Pg boundary in Oktibbeha County, Mississippi and subsequent comparison to other Early Paleogene and Late Cretaceous benthic marine macrofaunal localities. Comparison included previously collected material as well as specimens collected during this study in order to reconstruct the biological community living on the seafloor in the earliest Paleocene Mississippi Embayment. The primary fauna present after the K-Pg extinction was mainly composed of small …


Ide-Based Learning Analytics For Assessing Introductory Programming Skill, Phyllis J. Beck Aug 2023

Ide-Based Learning Analytics For Assessing Introductory Programming Skill, Phyllis J. Beck

Theses and Dissertations

Providing a sufficient level of personalized feedback on students' current level of strategic knowledge within the context of the natural programming environment through IDE-based learning analytics would transform learning outcomes for introductory programming students. However, providing sufficient insight into the programming process was previously inaccessible due to the need for more complex and scalable data collection methods and metrics with a wider variety for understanding programming metacognition and the full programming process.

This research developed a custom-built web-based IDE and event compression system to investigate two of the five components of a five-dimensional model of cognition for programming skill estimation …


Fabrication And Imaging Of Highly Ordered Plasmonic Au Nano-Prism And Self-Assembled Supramolecular Nanostructure, Ridwan Tobi Ayinla Aug 2023

Fabrication And Imaging Of Highly Ordered Plasmonic Au Nano-Prism And Self-Assembled Supramolecular Nanostructure, Ridwan Tobi Ayinla

Theses and Dissertations

The precise control of the resonance frequency of plasmonic nanostructures is critical and depends on the size, composition, shape, and dielectric nature of the environment. The ability to control the shape and size of nanomaterials acutely depends on the fabrication technique and material design. We used a cheap and scalable method known as nanosphere lithography (NSL) to fabricate plasmonic nano-prism (NP) on glass and indium tin oxide substrate (ITO). The methods involve substrate hydrophilicity treatment, polystyrene nanosphere masking, metal deposition, and mask removal. The array and specific morphology of the fabricated NP was established using scanning electron microscope (SEM) and …


Improved Stoichiometric Synthesis Of Ccc-Nhc Pincer Rh Complexes And Catalytic Activity Towards Dehydrogenative Silylation And Hydrosilylation Of Alkenes, Enock Amoateng Aug 2023

Improved Stoichiometric Synthesis Of Ccc-Nhc Pincer Rh Complexes And Catalytic Activity Towards Dehydrogenative Silylation And Hydrosilylation Of Alkenes, Enock Amoateng

Theses and Dissertations

N-Heterocyclic carbenes (NHCs) have attracted growing interest not only as successful ancillary ligands in a wide variety of transition-metal-catalyzed reactions but have also shown to offer photophysical and electrochemical properties. The metalation/transmetalation strategy using [Zr(NMe2)4] as initial metalating reagent offers an efficient approach to the preparation of CCC-NHC pincer complexes of the late transition metals such as Rh and Ir. In the process of investigating an intermediate and the mechanism of the metalation/transmetalation to Rh sequence, a mixed valent bimetallic CCC-NHC pincer Rh complex with two chloro ligands bridged between a [(CCC-NHC)Rh(III)] and a [Rh(I)(COD)] fragment …


A Four-Pronged Approach To Addressing A Wild Pig Invasion In A Bottomland And Upland Forested Landscape, Tyler Scott Evans Aug 2023

A Four-Pronged Approach To Addressing A Wild Pig Invasion In A Bottomland And Upland Forested Landscape, Tyler Scott Evans

Theses and Dissertations

Among exotic species that are capable of invading, establishing, and reaching pest status, few pose the range of impacts to biotic (e.g., competition with native species, predation, herbivory, introduction of other exotics) and abiotic (e.g., soil, hydrology) ecosystem components that can be attributed to the wild pig (Sus scrofa). Despite the presence of wild pigs throughout the southeastern United States for centuries, new invasions continue to occur in previously uninhabited and often under-investigated landscapes, including bottomland and upland forests. The recent invasion of the Sam D. Hamilton Noxubee National Wildlife Refuge (hereafter, NNWR) in east-central Mississippi represents an …


Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample Aug 2023

Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample

Theses and Dissertations

Increasing wetland restoration in the Lower Mississippi Alluvial Valley has been identified as a method to reduce nutrient loading in the Gulf of Mexico. Wetlands have historically been used to treat water through processes facilitated by wetland plants, and relatively few species and plant traits have been identified as important in carrying out these processes. This study focuses on some of those species and traits and aims to identify species differences and plant traits that may be important for wetland nutrient mitigation. Chapter I provides background information on nutrient pollution, wetland biogeochemical mechanisms for nutrient sequestration, and the focal species …


Expanding One-Dimensional Game Theory-Based Group Decision Models: Extension To N-Dimension And Integration Of Distributed Position Function, Mirhossein Mousavi Karimi Aug 2023

Expanding One-Dimensional Game Theory-Based Group Decision Models: Extension To N-Dimension And Integration Of Distributed Position Function, Mirhossein Mousavi Karimi

Theses and Dissertations

This dissertation aims to expand the current one-dimensional game theory based model to a multidimensional model for multi-actor predictive analytics and generalize the concept of position to address problems where actors’ positions are distributed over a position spectrum. The one-dimensional models are used for the problems where actors are interacting in a single issue space only. This is less than an ideal assumption since, in most cases, players’ strategies may depend on the dynamics of multiple issues when dealing with other players. In this research, the one-dimensional model is expanded to N-Dimensional model by considering different positions, and separate salience …


An Analysis Of Moisture Environments Associated With Mature North Atlantic Tropial Cyclones, Katherine Berislavich Aug 2023

An Analysis Of Moisture Environments Associated With Mature North Atlantic Tropial Cyclones, Katherine Berislavich

Theses and Dissertations

Tropical cyclone (TC) intensity and structure are affected by their environments, including sea surface temperature, vertical wind shear, and atmospheric moisture. Analyses of TC environments often rely on area-averaged quantities, yet the spatial variability of these fields can affect TC behavior, such as moisture distribution impacting where and how much rain falls. This study identifies spatial patterns of environmental moisture surrounding mature North Atlantic TCs during 2000-2021 in shear of less than 20 knots. Empirical orthogonal function analysis of total column water vapor reveals six dominant patterns. These patterns account for nearly 67% of the variance in the dataset and …


Trace Metal Analysis Of Pond Sediments To Measure Deposition From A Coal-Fired Power Plant In Ackerman Mississippi, Charles Bills Aug 2023

Trace Metal Analysis Of Pond Sediments To Measure Deposition From A Coal-Fired Power Plant In Ackerman Mississippi, Charles Bills

Theses and Dissertations

Trace element sediment pollution due to coal power plants have been reported in many countries. In this study, pond sediment samples collected from locations around a coal fired power plant in Ackerman, MS, were evaluated for their trace element concentration and pollution status. The samples were collected at two depths to study changes in element accumulation over time. The samples were digested and the elements, As, Cd, Cr, Cu, Pb, Hg, and Zn were analyzed using ICP-MS. Results were then compared to known background concentrations as well as sediment quality guidelines and pollution thresholds. The sample locations downwind of the …


Visual And Spatial Audio Mismatching In Virtual Environments, Zachary Lawrence Garris Aug 2023

Visual And Spatial Audio Mismatching In Virtual Environments, Zachary Lawrence Garris

Theses and Dissertations

This paper explores how vision affects spatial audio perception in virtual reality. We created four virtual environments with different reverb and room sizes, and recorded binaural clicks in each one. We conducted two experiments: one where participants judged the audio-visual match, and another where they pointed to the click direction. We found that vision influences spatial audio perception and that congruent audio-visual cues improve accuracy. We suggest some implications for virtual reality design and evaluation.


Optimizing Edge-Of-Field Water Quality Monitoring Methods To Determine The Effects Of Best Management Practices On Nutrient And Sediment Runoff, Mark Hill Aug 2023

Optimizing Edge-Of-Field Water Quality Monitoring Methods To Determine The Effects Of Best Management Practices On Nutrient And Sediment Runoff, Mark Hill

Theses and Dissertations

This study investigates the impact on water quality of combined agricultural best management practices cover crop and minimum tillage, alongside an examination of techniques used to collect those samples. Edge-of-field (EOF) water quality samples were collected from 11 working farms during a two-year paired field experiment. Results showed significant reductions in nutrient concentrations, increased discharge, and mixed findings regarding nutrient mass transport post-treatment. A suite of EOF collection techniques were compared using in-situ automated water sampling systems sampling the same runoff events. Sampling protocols influenced nutrient concentrations in composite samples, but unexpected variance in velocity sensors affected measured discharge, making …


Draft Final 2023 Rmap Baptist Student Union (Former Mckinley School) Soil Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc. Aug 2023

Draft Final 2023 Rmap Baptist Student Union (Former Mckinley School) Soil Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Draft Final 2023 Residential Metals Abatement Program (Rmap) Stodden Park Soil Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc. Aug 2023

Draft Final 2023 Residential Metals Abatement Program (Rmap) Stodden Park Soil Remedial Action Work Plan (Rawp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.