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Articles 3901 - 3930 of 302419

Full-Text Articles in Physical Sciences and Mathematics

Intriguing Properties Of Data Attribution On Diffusion Models, Xiaosen Zheng, Tianyu Pang, Chao Du, Jing Jiang, Xiaosen Zheng May 2024

Intriguing Properties Of Data Attribution On Diffusion Models, Xiaosen Zheng, Tianyu Pang, Chao Du, Jing Jiang, Xiaosen Zheng

Research Collection School Of Computing and Information Systems

Data attribution seeks to trace model outputs back to training data. With the recent development of diffusion models, data attribution has become a desired module to properly assign valuations for high-quality or copyrighted training samples, ensuring that data contributors are fairly compensated or credited. Several theoretically motivated methods have been proposed to implement data attribution, in an effort to improve the trade-off between computational scalability and effectiveness. In this work, we conduct extensive experiments and ablation studies on attributing diffusion models, specifically focusing on DDPMs trained on CIFAR-10 and CelebA, as well as a Stable Diffusion model LoRA-finetuned on ArtBench. …


The Role Of Student Motivation In Integrating Ai Into Web Design Education: A Longitudinal Study, Jason Lively, James Hutson May 2024

The Role Of Student Motivation In Integrating Ai Into Web Design Education: A Longitudinal Study, Jason Lively, James Hutson

Faculty Scholarship

Amidst the current wave studies of artificial intelligence (AI) in education, this longitudinal case study, spanning Spring 2023 to Spring 2024, delves into the integration of AI in the UI/UX web design classroom. By introducing both text-based and image-based AI tools to students with varying levels of skill in introductory web design and user experience (UX) courses, the study observed a significant enhancement in student creative capabilities and project outcomes. The utilization of text-based generators markedly improved writing efficiency and coding, while image-based tools facilitated better ideation and color selection. These findings underscore the potential to augment traditional educational methods, …


Optimizing Adult Learner Success: Applying Random Forest Classifier In Higher Education Predictive Analytics, Emily Barnes, James Hutson, Karriem Perry May 2024

Optimizing Adult Learner Success: Applying Random Forest Classifier In Higher Education Predictive Analytics, Emily Barnes, James Hutson, Karriem Perry

Faculty Scholarship

This study examines the application of the Random Forest Classifier (RF) model in predicting academic success among adult learners in higher education. It focuses on evaluating the model's effectiveness using key statistical measures like accuracy, precision, recall, and F1 score across a comprehensive dataset from 2013–14 to 2021–22, which includes variables such as age, ethnicity, gender, Pell Grant eligibility, and academic performance metrics. The research highlights the RF model's capability to handle large datasets with varying data types and demonstrates its superiority over traditional regression models in predictive accuracy. Through an iterative process, the study refines the RF model to …


Local Existence Of Solutions To A Nonlinear Autonomous Pde Model For Population Dynamics With Nonlocal Transport And Competition, Michael R. Lindstrom May 2024

Local Existence Of Solutions To A Nonlinear Autonomous Pde Model For Population Dynamics With Nonlocal Transport And Competition, Michael R. Lindstrom

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Highlights

  • Partial differential equation models are ubiquitous in applied sciences.

  • A partial differential equation based in ecology is studied for solution existence.

  • Energy methods and convergence analysis lead to local classical solutions.

Abstract

In this paper, we prove that a particular nondegenerate, nonlinear, autonomous parabolic partial differential equation with nonlocal mass transfer admits the local existence of classical solutions. The equation was developed to qualitatively describe temporal changes in population densities over space through accounting for location desirability and fast, long-range travel. Beginning with sufficiently regular initial conditions, through smoothing the PDE and employing energy arguments, we obtain a sequence …


Determining The Viability Of Marine Sensor Construction, Roman Sequeira May 2024

Determining The Viability Of Marine Sensor Construction, Roman Sequeira

Honors College

I intend to determine the viability of building a sensor that can be deployed in marine environments. Viability is defined as a summary of economic affordability, practicality of construction and deployment, knowledge required, and effectiveness. In order to get the best results, our sensor must be able to be modified to suit individual circumstances, constructed out of easy to obtain materials, be robust enough to withstand less than lab grade environments, and most importantly function well enough to be worth the effort of building it. I have built a sensor using the cheapest and most widely available options available. It …


Ghost Connect-Net: A Connectivity-Based Companion Network To Enhance Pruning Methods, Mary Isabelle Wisell May 2024

Ghost Connect-Net: A Connectivity-Based Companion Network To Enhance Pruning Methods, Mary Isabelle Wisell

Honors College

Deep neural network (DNN) approaches excel in various real-world applications like robotics and computer vision, yet their computational demands and memory requirements hinder usability on advanced devices. Also, larger models heighten overparameterization risks, making networks more vulnerable to input disturbances. Recent studies aim to boost DNN efficiency by trimming redundant neurons or filters based on task relevance. Instead of introducing a new pruning method, this project aims to enhance existing techniques by introducing a companion network, Ghost Connect-Net (GC-Net), to monitor the connections in the original network. The initial weights of GC- Net are equal to the connectivity measurements of …


The Conservation Project: An Exploration Of Multimedia In Ocean Conservation, Ilaria Bardini May 2024

The Conservation Project: An Exploration Of Multimedia In Ocean Conservation, Ilaria Bardini

Honors College

The Conservation Project ties in many elements of multimedia and its possible applications in marine conservation. The purpose of this thesis was to develop new skills in videography, photography, podcast production, and website development through which to deepen my understanding of the multimedia as a tool in science, through the development of a website.


Understanding The Connection Between Water, Fish, And Pfas Concentrations: Implications Of Fish Diet And Species-Specific Variability, Ece Yeldan May 2024

Understanding The Connection Between Water, Fish, And Pfas Concentrations: Implications Of Fish Diet And Species-Specific Variability, Ece Yeldan

Honors College

Perfluoroalkyl and polyfluoroalkyl substances, commonly known as PFAS or “forever chemicals,” have emerged as a significant concern for both human health and the environment. These persistent compounds permeate various aspects of commerce, leading to widespread exposure and the cycling of these compounds through environmental feedback routes. Among the sources of exposure to humans, fish consumption stands out prominently. Recreational and sustenance fishing, cherished by Maine residents and indigenous communities alike, underscores the need to comprehend PFAS dynamics in fish and water. To explore the variability of PFAS accumulation in fish, water, and sediment, I conducted a comprehensive literature review. The …


Assessing The Influence Of Interseeded Cover Crops On Beneficial Arthropod Abundance In A Northeastern Agroecosystem, Charles Cooper May 2024

Assessing The Influence Of Interseeded Cover Crops On Beneficial Arthropod Abundance In A Northeastern Agroecosystem, Charles Cooper

Honors College

Conservation agriculture approaches are gaining traction as the planet’s food system grapples with climate change, oil depletion, and rampant environmental degradation (Palm et al., 2014). Cover cropping is an integral practice of conservation agriculture. Ground dwelling arthropods play an important role in agroecosystems, providing ecosystem services including seed predation and nutrient cycling. Because the relationship between cover crops and arthropod abundance are likely influenced by management conditions, I investigated arthropod abundance in a field interseeded with cover crops on a research farm in Maine, United States. Interseeding is an emerging practice in the northeastern United States, with potential to address …


Using Cdom Optical Properties To Estimate Its Source, Distribution, And Doc Conentration In Maine Estuaries, Camille Michaud May 2024

Using Cdom Optical Properties To Estimate Its Source, Distribution, And Doc Conentration In Maine Estuaries, Camille Michaud

Honors College

Colored dissolved organic matter (CDOM) contributes largely to ocean color, and therefore, influences processes and applications that interact with light in the ocean such as remote sensing and biogeochemistry. It is a component part of dissolved organic carbon (DOC) and there is a strong relationship in coastal waters between CDOM absorption and DOC concentration. CDOM optical properties also vary with salinity and source. These important aspects of CDOM absorption led us to collect CDOM samples across the salinity gradients of 3 estuaries in Maine: the Penobscot, Damariscotta, and Sheepscot. We sampled stations along the salinity gradient in each estuary from …


Ecological Effects And Ethics Of A Species Range Shift To High Elevation Ponds, Ava Ardito May 2024

Ecological Effects And Ethics Of A Species Range Shift To High Elevation Ponds, Ava Ardito

Honors College

As temperatures warm, the climate crisis is having a significant influence on species across the world and altering their distributions. Colorado's high elevation ponds have recently observed a species range shift, traveling to higher altitudes than they have previously inhabited. The Mexican Cut Nature Preserve near the Rocky Mountain Biological Laboratory (RMBL) in Gothic, CO, is home to a prominent caddisfly Limnephilus externus, but recently a new range-shifting species, Nemotaulius hostilis, has appeared. Caddisflies play an essential role in nutrient cycling and putting energy back into the food web. The range-shifting species is known to excrete high rates of phosphorus …


Evaluating The Accuracy Of Different Remote Sensing Methods Used To Derive Absorption From Chromophoric Dissolved Organic Matter In Maine Estuaries, Andrea Rudai May 2024

Evaluating The Accuracy Of Different Remote Sensing Methods Used To Derive Absorption From Chromophoric Dissolved Organic Matter In Maine Estuaries, Andrea Rudai

Honors College

Current knowledge of dissolved organic carbon (DOC) in Maine estuaries is based on limited field research. By using chromophoric dissolved organic matter (CDOM) as a proxy, it is possible to use satellite images to estimate the concentration of DOC in an entire body of water. This study aims to evaluate different methods that calculate absorption by CDOM from ocean color remote sensing using images taken by Landsat 9 of the Sheepscot, Penobscot, and Damariscotta rivers. The study revealed that although there were some similarities in along-estuary trends between the remotely- sensed absorption and absorption measured in situ, the algorithms that …


Analysis Of Nonsmooth Neural Mass Models, Cadi Howell May 2024

Analysis Of Nonsmooth Neural Mass Models, Cadi Howell

Honors College

Neural activity in the brain involves a series of action potentials that represent “all or nothing” impulses. This implies the action potential will only “fire” if the mem- brane potential is at or above a specific threshold. The Wilson-Cowan neural mass model [6, 28] is a popular mathematical model in neuroscience that groups excita- tory and inhibitory neural populations and models their communication. Within the model, the on/off behavior of the firing rate is typically modeled by a smooth sigmoid curve. However, a piecewise-linear (PWL) firing rate function has been considered in the Wilson-Cowan model in the literature (e.g., see …


Physical Forcing Of Productivity, Biomass, And Demography Of Ascophyllum Nodosum, Henry Guy May 2024

Physical Forcing Of Productivity, Biomass, And Demography Of Ascophyllum Nodosum, Henry Guy

Honors College

The intertidal coastlines of Maine are dominated by a near monoculture of Ascophyllum nodosum. This species of macroalgae is foundational to the ecosystems in which it inhabits, so what controls the Ascophyllum nodosum controls the coasts. A. nodosum has been documented as a steady-state species in terms of biomass, canopy height, and primary productivity. Algal biomass results from algal recruitment, primary productivity (growth rate), and environmental disturbance (rate of biomass loss). My study estimated the abiotic disturbance of the environment on biotic factors ofAscophyllum nodosum. Physical forcings of the environment, ice, water motion, and light, drive Ascophyllum nodosum abundance, distribution, …


Microplastics: The Relationship Between Wastewater And Amount Of Microplastics In The Environment, Julia Muth May 2024

Microplastics: The Relationship Between Wastewater And Amount Of Microplastics In The Environment, Julia Muth

Honors College

In this paper, the contribution of wastewater to the cycle of microplastics in the environment is addressed. Several articles, journal papers and reliable websites were consulted for a literature review on this topic. The sources suggest that approximately 10% of the plastics in the influent exit in the effluent, and further analysis showed that the effluent wastewater and sludge produced in the USA contributes approximately 89,100 tons of plastic yearly (Basic Information about Biosolids 2023; Carr, Liu, and Tesoro 2016; Center for Sustainable Systems 2023; EPA 2023; Okoffo, Tscharke, and Thomas 2023). This outflow of plastic into the environment causes …


An Investigation Into Problem Solving In The Calculus Iii Classroom, Joseph Godinez May 2024

An Investigation Into Problem Solving In The Calculus Iii Classroom, Joseph Godinez

Honors College

The importance of tertiary education has grown to new heights, especially in the United States. A critical component of successful modern professionals remains the ability to employ problem-solving strategies and techniques. This study seeks to investigate initial problem-solving strategies employed by post-secondary students enrolled in Calculus II when presented with problems common to integral calculus. In- person pair-wise interviews were conducted asking six participants to sort integrals into categories based on the technique they would use to solve it. Participant responses were analyzed using a concept image composed of general and topic-specific symbolic forms, related conceptual images and concept definitions, …


Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre May 2024

Characterization Of Carbonaceous Fault Rocks, Pioneer Fault Zone, South-Central Idaho, Genna Baldassarre

All Graduate Reports and Creative Projects, Fall 2023 to Present

Differing crystallinities of carbonaceous material are common in fault rocks across a range of geologic settings and spatial scales and may provide constraints on strain rate, the nature of fault slip, fluid-rock interactions, and temperature variations over the earthquake cycle. The Pioneer fault at Little Fall Creek in south-central Idaho provides an excellent opportunity to study nanostructure changes of carbonaceous matter as a function of fault deformation. At this location, the Pioneer Fault exhibits a well-defined principal slip zone (PSZ) composed of multi-layered white siliceous mineralization and black carbon to graphite with a continuously exposed adjacent damage zone that includes …


Exploring Optimal Design Of Experiments For Random Effects Models, Ryan C. Bushman May 2024

Exploring Optimal Design Of Experiments For Random Effects Models, Ryan C. Bushman

All Graduate Theses and Dissertations, Fall 2023 to Present

The majority of research in the field of optimal design of experiments has focused on producing designs for fixed effects models. The purpose of this thesis is to explore how the optimal design framework applies to nested random effects models. The object that is being optimized is the model information matrix. We explore the full derivation of the random effects information matrix to highlight the complexity of the problem and show how the optimization is a function of the model's parameters. In conjunction with this research, the ODVC (Optimal Design for Variance Components) package was built to provide tools that …


Inferring A Hierarchical Input Type For An Sql Query, Santosh Aryal May 2024

Inferring A Hierarchical Input Type For An Sql Query, Santosh Aryal

All Graduate Theses and Dissertations, Fall 2023 to Present

SQL queries are a common method to retrieve information from databases, much like asking a detailed question and getting a precise answer. Plug-and-play queries simplify the process of querying. In a Plug-and-play SQL query a programmer sketches the shape of the input to the query as a hierarchy. But the programmer could make a mistake in specifying the hierarchy and it takes programmer time and effort to specify the hierarchy. A better solution is to automatically infer the hierarchy from a query. This thesis presents a system to infer a hierarchical input type for an SQL query. We consider two …


Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo May 2024

Volcanic Glass As A Proxy For Paleotopography Suggests New Features In Late-Miocene Oregon, Julian Cohen, John Bershaw, Richard Hugo

Geology Faculty Publications and Presentations

Volcanic glass has been used extensively as a paleoaltimeter. Deuterium (2H) concentrations in glass have been found to be stable over geologic timescales, making δ2H (also known as δD) a reliable proxy for ancient water chemistry. However, continued work revolves around better understanding how different factors affect preserved water in volcanic ash. Here, we analyze δD in the Rattlesnake Tuff (RST), a widespread ca. 7 Ma ash-flow tuff, and create a paleoisoscape to assess variations in δD across Oregon during that time. To this end, 16 ash samples were collected across central and eastern Oregon from …


Plant-Plant Interaction In Early- Vs. Late-Successional Varieties Of The Hawaiian Landscape-Dominant Tree, Metrosideros Polymorpha, Tomoko Sakishima May 2024

Plant-Plant Interaction In Early- Vs. Late-Successional Varieties Of The Hawaiian Landscape-Dominant Tree, Metrosideros Polymorpha, Tomoko Sakishima

UNLV Theses, Dissertations, Professional Papers, and Capstones

Plant-plant interactions play an important role in assembling plant communities. Interactions between neighboring plants can vary as a result of the genetic relatedness of neighbors, impacting rates of growth and patterns of resource allocation. When growing alongside close relatives, some species decrease their growth in a form of cooperation, while others grow faster through facilitation. A complication of plant interaction studies arises because decreased growth in the presence of close relatives can also be due to competition for resources, which increases with phenotypic similarity. Further complicating matters, mycorrhizal fungi, through their connections with plant roots, may strongly influence plant interactions. …


Boron-Doped Diamond As A Resilient Electrode Material In Molten Salts, Hannah Katherine Patenaude May 2024

Boron-Doped Diamond As A Resilient Electrode Material In Molten Salts, Hannah Katherine Patenaude

UNLV Theses, Dissertations, Professional Papers, and Capstones

Molten salt chemistry has a range of applications within nuclear technology, including for the Molten Salt Reactors (MSRs) and pyroprocessing to recover valuable actinides for energy and national security needs. However, the high-temperature, corrosive nature of molten salts makes them particularly challenging to deploy on an industrial scale and study in benchtop measurements. Material accountability and corrosion monitoring of MSR fuels are essential components to the successful deployment of MSRs, and electroanalytical techniques like cyclic voltammetry (CV) and spectroelectrochemistry (SEC) can provide a wealth of information to describe salt systems in situ. To perform such measurements, it is imperative to …


Identifying Disease-Related Gene-Environment Interactions Based On Method Of Moments, Linchuan Shen May 2024

Identifying Disease-Related Gene-Environment Interactions Based On Method Of Moments, Linchuan Shen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Human diseases are often caused by a complex interplay of multiple factors, including genetics and environmental factors. These factors can play critical roles in the development and progression of diseases. Although genome-wide association studies (GWAS) have successfully identified many genetic variants associated with human diseases, the estimated effects of these variants are small and can explain only a relatively small portion of the heritability of the underlying diseases.

Detecting gene-environment interactions (G × E) can shed light on the biological mechanisms of diseases. However, most existing methods that investigate G × E only look at how one environmental …


Statistical Classification Using Selection And Ranking Methodologies With Statistical Learning, Jeong Jun Lee May 2024

Statistical Classification Using Selection And Ranking Methodologies With Statistical Learning, Jeong Jun Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

The subject of Statistical Classification is concerned with identifying and allocating future observations into one of the pre-categorized classes based on the characteristics of the objects. Typically, these decisions to classify and categorize the objects have been dependent on identifying a system of classification, and from there, determining attributes for sorting.

In past decades, from discriminant analysis, various methods have been developed for classification. In particular, the rise of artificial intelligence (AI), machine learning, and statistical learning theory has made it possible to consider improving the existing methods along with new developments and more comprehensive schemes in conjunction with data-driven …


Standard And Non-Standard Log-Linear Models For 2 × 2 Contingency Tables, G M Toufiqul Hoque May 2024

Standard And Non-Standard Log-Linear Models For 2 × 2 Contingency Tables, G M Toufiqul Hoque

UNLV Theses, Dissertations, Professional Papers, and Capstones

Log-linear models can be used to model the joint relationship of two or more categorical variables in a multiway contingency table. In a log-linear model, the logarithm of the expected joint counts (or the logarithm of the joint probabilities) in a contingency table can be written as a linear model.

Most log-linear models used in practice are standard. Standard log-linear models include the traditional parameter terms we see in ANOVA models: an overall effect, main effects, and various kinds of interaction terms.

Standard log-linear models are divided into hierarchical and non-hierarchical. Hierarchical models satisfy the hierarchy principle: if a higher-order …


Easier Air Alert Platform: A Design And Approach To Creating A Distributed Air Quality Monitoring And Alert System, Bryceton Bible May 2024

Easier Air Alert Platform: A Design And Approach To Creating A Distributed Air Quality Monitoring And Alert System, Bryceton Bible

Masters Theses

This thesis presents the design approach, development and implementation of the Elders Alert System for Imminent Environmental Risk (EASIER) project, an air quality monitoring and alert system aiming to improve the health and wellness of under-served elder communities, as a part of the Tennessee Valley Authority Connected Communities initiative for Environmental Justice. The EASIER project provides homes with a fully integrated, connected system capable of real-time air quality monitoring, notifications and descriptions of potential air quality risks, and educational material to empower these community members to take charge of their own air health. Further, EASIER aims to inform relevant family/friends …


White Cell Support Application For Expo Ops Tactical Wargame System, Zackery Joseph Milder May 2024

White Cell Support Application For Expo Ops Tactical Wargame System, Zackery Joseph Milder

Theses

The purpose of this project was to create a support application for a tabletop wargame currently used for training and scenario simulation by the United States Marine Corps. The EXPO OPS Companion is meant to enhance the capabilities of the White Cell/table director, the unbiased third party responsible for running adjudication for the EXPO OPS Tactical Wargames System. EXPO OPS TWS is “…a table top wargame covering contemporary and future conflict at the platoon, company and battalion level. It is a wargame toolkit that enables wargaming scenarios in the 2020 to 2030 timeframe. The design centers on plans and decisions …


Agriculture 4.0 And Beyond: Evaluating Cyber Threat Intelligence Sources And Techniques In Smart Farming Ecosystems, Hang T. Bui, Hamed Aboutorab, Arash Mahboubi, Yansong Gao, Nazatul H. Sultan, Aufeef Chauhan, Mohammad Z. Parvez, Michael Bewong, Rafiqul Islam, Zahid Islam, Seyit A. Camtepe, Praveen Gauravaram, Dineshkumar Singh, M. A. Babar, Shihao Yan May 2024

Agriculture 4.0 And Beyond: Evaluating Cyber Threat Intelligence Sources And Techniques In Smart Farming Ecosystems, Hang T. Bui, Hamed Aboutorab, Arash Mahboubi, Yansong Gao, Nazatul H. Sultan, Aufeef Chauhan, Mohammad Z. Parvez, Michael Bewong, Rafiqul Islam, Zahid Islam, Seyit A. Camtepe, Praveen Gauravaram, Dineshkumar Singh, M. A. Babar, Shihao Yan

Research outputs 2022 to 2026

The digitisation of agriculture, integral to Agriculture 4.0, has brought significant benefits while simultaneously escalating cybersecurity risks. With the rapid adoption of smart farming technologies and infrastructure, the agricultural sector has become an attractive target for cyberattacks. This paper presents a systematic literature review that assesses the applicability of existing cyber threat intelligence (CTI) techniques within smart farming infrastructures (SFIs). We develop a comprehensive taxonomy of CTI techniques and sources, specifically tailored to the SFI context, addressing the unique cyber threat challenges in this domain. A crucial finding of our review is the identified need for a virtual Chief Information …


Bridging Biological Systems With Social Behavior, Conservation, Decision Making, And Well-Being Through Hybrid Mathematical Modeling, Maggie Renee Sullens May 2024

Bridging Biological Systems With Social Behavior, Conservation, Decision Making, And Well-Being Through Hybrid Mathematical Modeling, Maggie Renee Sullens

Doctoral Dissertations

Mathematical modeling can achieve otherwise inaccessible insights into bio-logical questions. We use ODE (ordinary differential equations) and Game Theory models to demonstrate the breadth and power of these models by studying three very different biological questions, involving socio-behavioral and socio-economic systems, conservation biology, policy and decision making, and organismal homeostasis.

We adapt techniques from Susceptible-Infected-Recovered (SIR) epidemiological models to examine the mental well-being of a community facing the collapse of the industry on which it’s economically dependent. We consider the case study of a fishing community facing the extinction of its primary harvest species. Using an ODE framework with a …


Better Light Than Never: A New Radiative Mechanism For Observing Binary Black Holes, Paul Rioles May 2024

Better Light Than Never: A New Radiative Mechanism For Observing Binary Black Holes, Paul Rioles

Graduate Masters Theses

Black holes are notoriously elusive, they are impossible to observe directly, and cur- rent methods of extracting information from behind their cosmic camouflage are both limited in number and experimentally difficult. The scope of this investigation is to ex- plore a proposed novel radiative mechanism for active similar mass binary black holes, affording new observational methods to investigate frequency inspirals of BH mergers. The explored mechanism is a result of each BH’s accretion of the surrounding plasma, creating voids that orbit throughout the plasma. The significant results described in this thesis include expressions for the frequency, power radiated per unit …