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Hardware Trojan Detection Utilizing Graph Neural Networks And Structural Checking, Hunter Nauman May 2024

Hardware Trojan Detection Utilizing Graph Neural Networks And Structural Checking, Hunter Nauman

Graduate Theses and Dissertations

The integrated circuit (IC) industry has experienced exponential growth, particularly in the complexity and scale of hardware designs. To sustain this growth, faster development cycles and cost-effective solutions have been the focus for many companies. One strategy to maintain this growth is through the incorporation of third-party intellectual property (IP) into the IC design process. Outsourcing the production of sub-components reduces development time and enables faster time-to-market, however, this approach also introduces the threat of Hardware Trojans. Hardware Trojans, defined as any malicious modification or addition to an IC, pose significant security risks due to their small size, low activation …


Revealing The Three-Dimensional Arrangement Of Polar Topology In Nanoparticles, Chaewa Jeong, Juhyeok Lee, Hyesung Jo, Jaewhan Oh, Hionsuck Baik, Kyoung-June Go, Junwoo Son, Si-Young Choi, Sergey Prosandeev, Laurent Bellaiche, Yongsoo Yang May 2024

Revealing The Three-Dimensional Arrangement Of Polar Topology In Nanoparticles, Chaewa Jeong, Juhyeok Lee, Hyesung Jo, Jaewhan Oh, Hionsuck Baik, Kyoung-June Go, Junwoo Son, Si-Young Choi, Sergey Prosandeev, Laurent Bellaiche, Yongsoo Yang

Physics Faculty Publications and Presentations

In the early 2000s, low dimensional ferroelectric systems were predicted to have topologically nontrivial polar structures, such as vortices or skyrmions, depending on mechanical or electrical boundary conditions. A few variants of these structures have been experimentally observed in thin film model systems, where they are engineered by balancing electrostatic charge and elastic distortion energies. However, the measurement and classification of topological textures for general ferroelectric nanostructures have remained elusive, as it requires mapping the local polarization at the atomic scale in three dimensions. Here we unveil topological polar structures in ferroelectric BaTiO3 nanoparticles via atomic electron tomography, which …


Generalizations Of The Hardy Spaces And The Schwarz Boundary Value Problem, William L. Blair May 2024

Generalizations Of The Hardy Spaces And The Schwarz Boundary Value Problem, William L. Blair

Graduate Theses and Dissertations

We prove that many of the boundary properties associated with functions in the classic holomorphic Hardy spaces on the complex unit disk are present in Hardy classes of solutions to certain nonhomogeneous Cauchy-Riemann equations and higher-order generalizations of these equations. Also, we explicitly solve generalizations of the Schwarz boundary value problem on the complex unit disk and the upper-half plane when the boundary condition is in terms of boundary values in the sense of distributions.


Dyslexia Training: The Impact On The Perceptions And Knowledge-Base Of Pre-Professionals Preparing To Work In K-12 Educational Settings, Colby Fowler May 2024

Dyslexia Training: The Impact On The Perceptions And Knowledge-Base Of Pre-Professionals Preparing To Work In K-12 Educational Settings, Colby Fowler

Graduate Theses and Dissertations

This research explores the perceptions and understanding of dyslexia among first-year graduate students in speech-language pathology. Employing survey methodology, specifically a pre- and post-survey approach, this research investigates the attitudes and knowledge that the participants have in understanding and addressing dyslexia at the beginning of their graduate training. The study seeks to uncover the existing awareness, potential misconceptions, and the overall preparedness of these emerging professionals in dealing with individuals affected by dyslexia. Through a comprehensive survey analysis, the research aims to contribute valuable insights that can inform the development of targeted educational strategies and interventions within speech-language pathology programs, …


Characterizing The Role Of Chemo-Mechanical Couplings In The Activation Process Of Proteins That Undergo Conformational Changes, Ugochi Isu May 2024

Characterizing The Role Of Chemo-Mechanical Couplings In The Activation Process Of Proteins That Undergo Conformational Changes, Ugochi Isu

Graduate Theses and Dissertations

Proteins are not static entities; rather, they are dynamic macromolecules that undergo conformational changes to perform their biological functions. These structural transitions are often coupled to chemical events such as lipid interactions, or changes in the cellular environment. Understanding the intricate interplay between chemical perturbations and the resulting mechanical response is crucial for elucidating the activation mechanisms of proteins. This dissertation aims to characterize the role of chemo-mechanical couplings in the activation process of two G protein-coupled receptors (GPCRs): Cannabinoid Receptor 1 (CB1) and Metabotropic Glutamate Receptor 1 (mGluR1). We employ molecular dynamics simulations to investigate the conformational landscapes of …


Geochemical Analysis Of Basement Rock As A Potential Metal Source In Mississippi Valley-Type Ores, Southern Midcontinent U.S.A., Mackenzie Moorhead May 2024

Geochemical Analysis Of Basement Rock As A Potential Metal Source In Mississippi Valley-Type Ores, Southern Midcontinent U.S.A., Mackenzie Moorhead

Graduate Theses and Dissertations

Mississippi Valley-Type (MVT) ores are epigenetic, sedimentary hydrothermal base metal deposits that exist worldwide with type localities in the midcontinent United States. These Permian-aged sulfide ores represent an extraordinary concentration of economic metals, Pb and Zn. Ore deposits occur in vast districts that have a rich mining history. The Pb and Zn from these deposits account for 24% of worldwide reserves. The geologic processes responsible for MVT ore genesis are not fully understood, especially the sourcing of ore constituents. In the midcontinent, the Ouachita Orogeny expelled saline hydrothermal brines in response to high rates of subsidence. These fluids migrated through …


Towards Side-Channel Infrastructure For Software Implementations Of Pqc Algorithms, Tristen Teague May 2024

Towards Side-Channel Infrastructure For Software Implementations Of Pqc Algorithms, Tristen Teague

Graduate Theses and Dissertations

Post-Quantum Cryptography (PQC) is a new class of asymmetric cryptography algorithms that are supposed to be secure against both classical computers and quantum computers through Shor’s algorithm. Since PQC algorithms are currently being standardized, they will replace older standardized asymmetric algorithms (such as RSA) and will be deployed within the digital infrastructure. Before implementations of the PQC algorithms are placed into the infrastructure, they must undergo evaluation of both performance and security. One such security issue that needs large investigation before deployment are side-channels. Side-channel attacks (SCA) are a method of gathering information from the implementation, such as power-consumption and …


Fabrication And Characterization Of Black Phosphorus Terahertz Photoconductive Antennae, Katie Michelle Welch May 2024

Fabrication And Characterization Of Black Phosphorus Terahertz Photoconductive Antennae, Katie Michelle Welch

Graduate Theses and Dissertations

Advancements in terahertz (THz) imaging systems, particularly for applications like post-surgical analysis of breast cancer, have led to the exploration of novel materials such as black phosphorus as the active material for a THz photoconductive antenna (PCA). This thesis, motivated by innovative techniques developed at the University of Arkansas, investigates the potential of black phosphorus as a material to enhance the performance of THz PCAs, focusing on generation efficiency and bandwidth. Previous implementations of BP as THz emitters have shown limitations, highlighting the need for thorough material characterization and optimized fabrication processes. Therefore, we adopted a dual-phase approach to this …


Competition And Criticality In Cortical Neural Circuits Underlie Behavior And Optimize Working Memory, Jacob Harrison Barfield May 2024

Competition And Criticality In Cortical Neural Circuits Underlie Behavior And Optimize Working Memory, Jacob Harrison Barfield

Graduate Theses and Dissertations

One of the primary goals of neuroscience is to explain how brain function emerges from dynamic interactions among large populations of neurons. A long-standing hypothesis at the interface of physics and neuroscience posits that neural circuits may operate close to the critical point of a phase transition. In this dissertation, we will investigate a new form of criticality and the implications that it has in working memory and the generation of voluntary body movements. We will utilize this new form of criticality to investigate the functional benefits that can be harnessed by operating near the critical point when performing working …


Heterogenous Impacts Of Pathogenic Avian Diseases On Global Poultry Production, Elsbeth Hamilton May 2024

Heterogenous Impacts Of Pathogenic Avian Diseases On Global Poultry Production, Elsbeth Hamilton

Graduate Theses and Dissertations

Globally, poultry is one of the most versatile and cost-effective sources of animal-based protein. Due to its wide variety of uses and variability of growing styles, poultry production is applicable in nearly every country. With the increase of scale and concentration of production, pathogenic diseases have decreased the efficiency of production through worsened feed conversion, morbidity, and mortality. In addition to physiological health, climate largely impacts the suitable conditions for growing. With more extreme climate events, locations once ideal for poultry are less efficient due to increased resource cost. This analysis seeks to determine the heterogeneity of production and the …


Exploring Diversity, Discrimination, And Performance Dynamics, George Agyeah May 2024

Exploring Diversity, Discrimination, And Performance Dynamics, George Agyeah

Graduate Theses and Dissertations

This dissertation utilizes empirical and experimental approaches to investigate the multifaceted factors that affect decision-making in economic contexts. The three chapters place a particular focus on group affiliation, perceived discrimination, and the gender gap in entrepreneurship. The first chapter explores the impact of team diversity on economic decision-making within a dynamic context. Through a series of laboratory experiments involving participants randomly assigned to teams, the study examines how team diversity influences individual behavior and performance. Results indicate that team diversity significantly affects individual behavior, with newcomers being particularly influenced by the diversity of the team they join. The findings underscore …


Determining The Climatic Effects Of The Central Atlantic Magmatic Province Across The End Triassic Mass Extinction In The Elliot Formation, Southern Africa, Danielle Elizabeth Oberg May 2024

Determining The Climatic Effects Of The Central Atlantic Magmatic Province Across The End Triassic Mass Extinction In The Elliot Formation, Southern Africa, Danielle Elizabeth Oberg

Graduate Theses and Dissertations

Understanding the intricate relation between carbon-cycle perturbations, climate change, and biodiversity stability is crucial in the face of ongoing anthropogenic greenhouse-gas emissions. This thesis explores the impacts of rapid climate change induced by carbon-cycle perturbations and their potential repercussions on global climate. Large igneous provinces, particularly the Central Atlantic Magmatic Province, offer a lens through which to examine the nexus of volcanic activity, mass extinctions, and climate change. The emplacement of Central Atlantic Magmatic Province, covering vast regions across continents, emitted substantial amounts of carbon dioxide, profoundly impacting global climate and ecosystems. The end-Triassic Mass Extinction, attributed to Central Atlantic …


Two Studies: Aromatization-Driven Ring Opening Functionalization Of Unstrained Cycloalkanones Through Visible Light Catalysis, And Synthesis Of Amino Endoperoxides Using Self-Doped Titanium Dioxide (Ti3+@Tio2) As A Photocatalyst, Enoch Kudoahor May 2024

Two Studies: Aromatization-Driven Ring Opening Functionalization Of Unstrained Cycloalkanones Through Visible Light Catalysis, And Synthesis Of Amino Endoperoxides Using Self-Doped Titanium Dioxide (Ti3+@Tio2) As A Photocatalyst, Enoch Kudoahor

Graduate Theses and Dissertations

The pharmaceutical industry has been focused on discovering new innovative drugs over the last decade, but the syntheses are either inefficient or the approach to environmental sustainability raises significant concerns. Photochemistry and photocatalysis have found widespread applications in organic synthesis as a result of this pressing issue. Our role as organic chemists is to improve environmental quality by creating a "greener" world through the development of efficient synthetic methods and strategies. Solar energy is now one of the most abundant and renewable natural resources. The emergence of environmental sustainability concerns has led to the development of new techniques for harnessing …


Investigation Of K-2 Teachers' Self-Efficacy In One Rural School District, Crystal Schaefer May 2024

Investigation Of K-2 Teachers' Self-Efficacy In One Rural School District, Crystal Schaefer

Curriculum and Instruction Undergraduate Honors Theses

In the past four years education has undergone many changes, whether it be shifting to distance learning in 2020 or changing student behaviors, and these changes have undeniable effects on teachers and their self-efficacy. The purpose of this study is to investigate teachers’ sense of self-efficacy. A 24-question Qualtrics survey was distributed through email for kindergarten through second grade teachers between two elementary schools in one rural Arkansas school district. These 24 questions were adapted from The Teachers’ Sense of Efficacy Scale. The survey collected 16 total responses. The survey results provided evidence that teacher efficacy in instructional strategies is …


Agricultural Producer And Non-Producer Perceptions Of Crop Residue Burning: A Focus On Arkansas, Jillian Hyink, Ryan Bresnahan, Brandon R. Mcfadden, Aaron M. Shew, James Mitchell May 2024

Agricultural Producer And Non-Producer Perceptions Of Crop Residue Burning: A Focus On Arkansas, Jillian Hyink, Ryan Bresnahan, Brandon R. Mcfadden, Aaron M. Shew, James Mitchell

Agricultural Economics and Agribusiness Faculty Publications and Presentations

Agricultural producers adopt management practices that positively and negatively affect the lives of non-producers in their communities. CRB has important environmental and human health implications, and local non-producers might have different perceptions and attitudes from agricultural producers about crop residue burning. In this paper, we use a multi-stakeholder approach to study the issue of crop residue burning (CRB). Survey data were collected from a sample of producers in Arkansas who burn crop residue and a sample of non-producers who resided in the same counties as the producers. Non-producers may not be willing to compensate producers at an amount that would …


Genetic Dissection Of Diverse Seed Coat Patterns In Cowpea Through A Comprehensive Gwas Approach, Haizheng Xiong, Yilin Chen, Waltram Ravelombola, Beiquan Mou, Xiaolun Sun, Qingyang Zhang, Yiting Xiao, Yang Tian, Qun Luo, Ibtisam Alatawi, Kenani Edward Chiwina, Hanan Mohammedsaeed Alkabkabi, Ainong Shi May 2024

Genetic Dissection Of Diverse Seed Coat Patterns In Cowpea Through A Comprehensive Gwas Approach, Haizheng Xiong, Yilin Chen, Waltram Ravelombola, Beiquan Mou, Xiaolun Sun, Qingyang Zhang, Yiting Xiao, Yang Tian, Qun Luo, Ibtisam Alatawi, Kenani Edward Chiwina, Hanan Mohammedsaeed Alkabkabi, Ainong Shi

Poultry Science Faculty Publications and Presentations

This study investigates the genetic determinants of seed coat color and pattern variations in cowpea (Vigna unguiculata), employing a genome-wide association approach. Analyzing a mapping panel of 296 cowpea varieties with 110,000 single nucleotide polymorphisms (SNPs), we focused on eight unique coat patterns: (1) Red and (2) Cream seed; (3) White and (4) Brown/Tan seed coat; (5) Pink, (6) Black, (7) Browneye and (8) Red/Brown Holstein. Across six GWAS models (GLM, SRM, MLM, MLMM, FarmCPU from GAPIT3, and TASSEL5), 13 significant SNP markers were identified and led to the discovery of 23 candidate genes. Among these, four specific …


Spin Disorder Control Of Topological Spin Texture, Hongrui Zhang, Yu-Tsun Shao, Xiang Chen, Binhua Zhang, Tianye Wang, Fanhao Meng, Kun Xu, Peter Meisenheimer, Xianzhe Chen, Xiaoxi Huang, Piush Behera, Sajid Husain, Tiancong Zhu, Hao Pan, Yanli Jia, Nick Settineri, Nathan Giles-Donovan, Zehao He, Andreas Scholl, Alpha N'Diaye, Padraic Shafer, Archana Raja, Changsong Xu, Lane W. Martin, Michael F. Crommie, Jie Yao, Ziqiang Qiu, Arun Majumdar, Laurent Bellaiche, David A. Muller, Robert J. Birgeneau, Ramamoorthy Ramesh May 2024

Spin Disorder Control Of Topological Spin Texture, Hongrui Zhang, Yu-Tsun Shao, Xiang Chen, Binhua Zhang, Tianye Wang, Fanhao Meng, Kun Xu, Peter Meisenheimer, Xianzhe Chen, Xiaoxi Huang, Piush Behera, Sajid Husain, Tiancong Zhu, Hao Pan, Yanli Jia, Nick Settineri, Nathan Giles-Donovan, Zehao He, Andreas Scholl, Alpha N'Diaye, Padraic Shafer, Archana Raja, Changsong Xu, Lane W. Martin, Michael F. Crommie, Jie Yao, Ziqiang Qiu, Arun Majumdar, Laurent Bellaiche, David A. Muller, Robert J. Birgeneau, Ramamoorthy Ramesh

Physics Faculty Publications and Presentations

Stabilization of topological spin textures in layered magnets has the potential to drive the development of advanced low-dimensional spintronics devices. However, achieving reliable and flexible manipulation of the topological spin textures beyond skyrmion in a two-dimensional magnet system remains challenging. Here, we demonstrate the introduction of magnetic iron atoms between the van der Waals gap of a layered magnet, Fe3GaTe2, to modify local anisotropic magnetic interactions. Consequently, we present direct observations of the order-disorder skyrmion lattices transition. In addition, non-trivial topological solitons, such as skyrmioniums and skyrmion bags, are realized at room temperature. Our work highlights …


Algorithm-Based Linearly Graded Compositions Of Gesn On Gaas (001) Via Molecular Beam Epitaxy, Calbi Gunder, Mohammad Zamani-Alavijeh, Emmanuel Wangila, Fernando Maia De Oliveira, Aida Sheibani, Serhii Kryvyi, Paul C. Attwood, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo May 2024

Algorithm-Based Linearly Graded Compositions Of Gesn On Gaas (001) Via Molecular Beam Epitaxy, Calbi Gunder, Mohammad Zamani-Alavijeh, Emmanuel Wangila, Fernando Maia De Oliveira, Aida Sheibani, Serhii Kryvyi, Paul C. Attwood, Yuriy I. Mazur, Shui-Qing Yu, Gregory J. Salamo

Physics Faculty Publications and Presentations

The growth of high-composition GeSn films in the future will likely be guided by algorithms. In this study, we show how a logarithmic-based algorithm can be used to obtain high-quality GeSn compositions up to 16% on GaAs (001) substrates via molecular beam epitaxy. Herein, we use composition targeting and logarithmic Sn cell temperature control to achieve linearly graded pseudomorph Ge1−xSnx compositions up to 10% before partial relaxation of the structure and a continued gradient up to 16% GeSn. In this report, we use X-ray diffraction, simulation, secondary ion mass spectrometry, and atomic force microscopy to analyze and …


Computational Fluid Dynamics Analysis And Empirical Evaluation Of Carboxymethylcellulose/Alginate 3d Bioprinting Inks For Screw-Based Microextrusion, Sungmin Lee, Minjae Son, Juo Lee, Iksong Bun, Jin-Woo Kim, Jungsil Kim, Hoon Seonwoo Apr 2024

Computational Fluid Dynamics Analysis And Empirical Evaluation Of Carboxymethylcellulose/Alginate 3d Bioprinting Inks For Screw-Based Microextrusion, Sungmin Lee, Minjae Son, Juo Lee, Iksong Bun, Jin-Woo Kim, Jungsil Kim, Hoon Seonwoo

Biological and Agricultural Engineering Faculty Publications and Presentations

Three-dimensional microextrusion bioprinting technology uses pneumatics, pistons, or screws to transfer and extrude bioinks containing biomaterials and cells to print biological tissues and organs. Computational fluid dynamics (CFD) analysis can simulate the flow characteristics of bioinks in a control volume, and the effect on cell viability can be predicted by calculating the physical quantities. In this study, we developed an analysis system to predict the effect of a screw-based dispenser system (SDS) on cell viability in bioinks through rheological and CFD analyses. Furthermore, carboxymethylcellulose/alginate-based bioinks were used for the empirical evaluation of high-viscous bioinks. The viscosity of bioinks was determined …


Ssnet: Exploiting Spatial Information For Tobacco Stem Impurity Detection With Hyperspectral Imaging, Chao Zhou, Zhenye Li, Dongyi Wang, Sheng Xue, Tingting Zhu, Chao Ni Apr 2024

Ssnet: Exploiting Spatial Information For Tobacco Stem Impurity Detection With Hyperspectral Imaging, Chao Zhou, Zhenye Li, Dongyi Wang, Sheng Xue, Tingting Zhu, Chao Ni

Biological and Agricultural Engineering Faculty Publications and Presentations

Tobacco stems are a critical component in cigarette production in China. However, accurately and promptly identifying impurities in tobacco stems remains a challenge with current deep learning methods, often failing to meet industry standards. This study introduces the Spectral-Spatial Network (SSNet), which is specifically optimized for rapid and precise detection of impurities in tobacco stems, leveraging spatial information in hyperspectral imaging. Designed to align with the high-speed requirements of industrial processing, SSNet effectively overcomes the complexities associated with analyzing hyperspectral data. The integration of spatial information particularly enhances recognition accuracy, especially in areas affected by fringe patterns. Our experiments reveal …


Rotational Magnetoelectric Switching In Orthorhombic Multiferroics, Xu Li, Hao Tian, Hongjun Jiang, Jun-Ming Liu, L. Bellaiche, Yurong Yang Apr 2024

Rotational Magnetoelectric Switching In Orthorhombic Multiferroics, Xu Li, Hao Tian, Hongjun Jiang, Jun-Ming Liu, L. Bellaiche, Yurong Yang

Physics Faculty Publications and Presentations

Controlling the direction of ferromagnetism and antiferromagnetism by an electric field in single-phase multiferroics will open the door to the next generation of devices for spintronics and electronics. The typical magnetoelectric coupling such as the linear magnetoelectric effect is very weak in type-I multiferroics and therefore the magnetoelectric switching is rarely achieved. Here, using first- principles simulations, we propose a magnetoelectric switching mechanism to achieve such highly desired control in orthorhombic multiferroics. One class of two-dimensional proper multiferroics (CrX2Se3 and MnX2Te3, X = Sn, Ge) and perovskite multiferroics (EuTiO3 and BiFeO3/LaFeO3 superlattice) are taken as examples to show the mechanism. …


Group Iv Topological Quantum Alloy And The Role Of Short-Range Order: The Case Of Ge-Rich Ge1–XPbX, Yunfan Liang, Shunda Chen, Xiaochen Jin, Damien West, Shui-Qing Yu, Tianshu Li, Shengbai Zhang Apr 2024

Group Iv Topological Quantum Alloy And The Role Of Short-Range Order: The Case Of Ge-Rich Ge1–XPbX, Yunfan Liang, Shunda Chen, Xiaochen Jin, Damien West, Shui-Qing Yu, Tianshu Li, Shengbai Zhang

Electrical Engineering and Computer Science Faculty Publications and Presentations

Despite the explosion of interest in topological materials over the last decades, their applications remain limited due to challenges in growth and incorporation with today’s microelectronics. As a potential bridge to close this gap, we investigate the group-IV alloy Ge1–xPbx, in the Ge-rich condition using density functional theory and show that relatively low concentrations of Pb (~9.4%) can lead to a topological phase transition. Furthermore, the calculation of the Z2 invariant for both the random alloy and the alloy with short-range order (SRO) indicate that the topological phase of the material can be directly modified …


Modeling, Characterization, And Machine Learning Algorithm For Rectangular Choke Horn Antennas, Ibrahim N. Alquaydheb, Saleh A. Alfawaz, Amirreza Ghadimi Avval, Sara Ghayouraneh, Samir M. El-Ghazaly Apr 2024

Modeling, Characterization, And Machine Learning Algorithm For Rectangular Choke Horn Antennas, Ibrahim N. Alquaydheb, Saleh A. Alfawaz, Amirreza Ghadimi Avval, Sara Ghayouraneh, Samir M. El-Ghazaly

Electrical Engineering and Computer Science Faculty Publications and Presentations

In this work, we present the design and modeling of a new type of choke horn antenna. It incorporates a rectangular waveguide and a rectangular choke acting as a parasitic element. The four-sided geometry of the antenna is applicable to systems that utilize rectangular waveguides. Also, it can overcome the need for rectangular-to-circular transition of transmission line or mode conversion. The main objective of this paper is to develop a model that calculates the far field radiation characteristics of the proposed antenna (analytical part) and to incorporate a finite element method (FEM) solver that adds to the theoretical solution (empirical …


Remote, Rugged Field Scenarios For Archaeology And The Field Sciences: Object Avoidance And 3d Flight Planning With Suas Photogrammetry, Carla Klehm, Malcolm D. Williamson, Leland C. Bement, Brandi Bethke Apr 2024

Remote, Rugged Field Scenarios For Archaeology And The Field Sciences: Object Avoidance And 3d Flight Planning With Suas Photogrammetry, Carla Klehm, Malcolm D. Williamson, Leland C. Bement, Brandi Bethke

Center for Advanced Spatial Technologies Publications and Presentations

Advances built into recent sUASs (drones) offer a compelling possibility for field-based data collection in logistically challenging and GPS-denied environments. sUASs-based photogrammetry generates 3D models of features and landscapes, used extensively in archaeology as well as other field sciences. Until recently, navigation has been limited by the expertise of the pilot, as objects, like trees, and vertical or complex environments, such as cliffs, create significant risks to successful documentation. This article assesses sUASs’ capability for autonomous obstacle avoidance and 3D flight planning using data collection scenarios carried out in Black Mesa, Oklahoma. Imagery processed using commercial software confirmed that the …


Implications Of Minimum Description Length For Adversarial Attack In Natural Language Processing, Kshitiz Tiwari, Lu Zhang Apr 2024

Implications Of Minimum Description Length For Adversarial Attack In Natural Language Processing, Kshitiz Tiwari, Lu Zhang

Electrical Engineering and Computer Science Faculty Publications and Presentations

Investigating causality to establish novel criteria for training robust natural language processing (NLP) models is an active research area. However, current methods face various challenges such as the difficulties in identifying keyword lexicons and obtaining data from multiple labeled environments. In this paper, we study the problem of robust NLP from a complementary but different angle: we treat the behavior of an attack model as a complex causal mechanism and quantify its algorithmic information using the minimum description length (MDL) framework. Specifically, we use masked language modeling (MLM) to measure the “amount of effort” needed to transform from the original …


Efficient Photocatalytic Core–Shell Synthesis Of Titanate Nanowire/Rgo, Xiaofang Ye, Yang Tian, Mengyao Gao, Fangjun Cheng, Jinshen Lan, Han Chen, Mark Lanoue, Shengli Huang, Z. Ryan Tian Apr 2024

Efficient Photocatalytic Core–Shell Synthesis Of Titanate Nanowire/Rgo, Xiaofang Ye, Yang Tian, Mengyao Gao, Fangjun Cheng, Jinshen Lan, Han Chen, Mark Lanoue, Shengli Huang, Z. Ryan Tian

Chemistry & Biochemistry Faculty Publications and Presentations

Wide bandgap semiconductor-based photocatalysts are usually limited by their low solar energy conversion efficiency due to their limited absorption solar wavelength, their rapid surface recombination of the photogenerated electron–hole pairs, and their low charge-carrier mobility. Here, we report a novel stepwise solution synthesis for achieving a new photocatalytic core–shell consisting of a titanate nanowire/reduced graphene oxide shell (or titanate/rGO) 1D-nanocomposite. The new core–shell nanocomposite maximized the specific surface area, largely reduced the charge transfer resistance and reaction energy barrier, and significantly improved the absorption of visible light. The core–shell nanocomposites’ large on/off current ratio and rapid photo-responses boosted the photocurrent …


Low-Dimensional Criticality Embedded In High-Dimensional Awake Brain Dynamics, Antonio J. Fontenele, J. Samuel Sooter, V. Kindler Norman, Shree Hari Gautam, Woodrow L. Shew Apr 2024

Low-Dimensional Criticality Embedded In High-Dimensional Awake Brain Dynamics, Antonio J. Fontenele, J. Samuel Sooter, V. Kindler Norman, Shree Hari Gautam, Woodrow L. Shew

Physics Faculty Publications and Presentations

Whether cortical neurons operate in a strongly or weakly correlated dynamical regime determines fundamental information processing capabilities and has fueled decades of debate. We offer a resolution of this debate; we show that two important dynamical regimes, typically considered incompatible, can coexist in the same local cortical circuit by separating them into two different subspaces. In awake mouse motor cortex, we find a low-dimensional subspace with large fluctuations consistent with criticality—a dynamical regime with moderate correlations and multi-scale information capacity and transmission. Orthogonal to this critical subspace, we find a high-dimensional subspace containing a desynchronized dynamical regime, which may optimize …


Design And Fabrication Of Electrochemical Sensor Based On Nio/Ni@C-Fe3o4/Ceo2 For The Determination Of Niclosamide, Setayesh Darvishi, Ali A. Ensafi, Kimia Zarean Mousaabadi Mar 2024

Design And Fabrication Of Electrochemical Sensor Based On Nio/Ni@C-Fe3o4/Ceo2 For The Determination Of Niclosamide, Setayesh Darvishi, Ali A. Ensafi, Kimia Zarean Mousaabadi

Chemistry & Biochemistry Faculty Publications and Presentations

In this study, we aimed to enhance and accelerate the electrochemical properties of a glassy carbon-based voltammetric sensor electrode. This was achieved through the modification of the electrode using a nanocomposite derived from a metal–organic framework, which was embedded onto a substrate consisting of metal oxide nanoparticles. The final product was an electrocatalyst denoted as NiO/Ni@C-Fe3O4/CeO2, tailored for the detection of the drug niclosamide. Several techniques, including FT-IR, XRD, XPS, FE-SEM, TEM, and EDS, were employed to characterize the structure and morphology of this newly formed electroactive catalyst. Subsequently, the efficiency of this electrocatalyst …


We Need A Solid Scientific Basis For Nature-Based Climate Solutions In The United States, Kimberly A. Novick, Trevor F. Keenan, William R. L. Anderegg, Caroline P. Normile, Benjamin R. Runkle, Emily E. Oldfield, Gyami Shrestha, D. D. Baldocchi, Margaret E.K. Evans, James T. Randerson, Jonathan Sanderman, Margaret S. Torn, Anna T. Trugman, Christopher A. Williams Mar 2024

We Need A Solid Scientific Basis For Nature-Based Climate Solutions In The United States, Kimberly A. Novick, Trevor F. Keenan, William R. L. Anderegg, Caroline P. Normile, Benjamin R. Runkle, Emily E. Oldfield, Gyami Shrestha, D. D. Baldocchi, Margaret E.K. Evans, James T. Randerson, Jonathan Sanderman, Margaret S. Torn, Anna T. Trugman, Christopher A. Williams

Biological and Agricultural Engineering Faculty Publications and Presentations

Nature-based climate solutions (NbCS) have courted both enthusiastic support and considerable controversy (1–8). Defined as deliberate human actions that manipulate ecosystems to improve the planet’s greenhouse gas balance, NbCS provoke disagreement, in large part because their implementation has so far outpaced a science-based understanding of their long-term climate mitigation potential.


Different Currencies For Calculating Resource Phenology Result In Opposite Inferences About Trophic Mismatches, Tom S. L. Versluijs, Mikhail K. Zhemchuzhnikov, Dmitry Kutcherov, Tomas Roslin, Niels Martin Schmidt, Jan A. Van Gils, Jeroen Reneerkens Mar 2024

Different Currencies For Calculating Resource Phenology Result In Opposite Inferences About Trophic Mismatches, Tom S. L. Versluijs, Mikhail K. Zhemchuzhnikov, Dmitry Kutcherov, Tomas Roslin, Niels Martin Schmidt, Jan A. Van Gils, Jeroen Reneerkens

Biological Sciences Faculty Publications and Presentations

Shifts in phenology are among the key responses of organisms to climate change. When rates of phenological change differ between interacting species they may result in phenological asynchrony. Studies have found conflicting patterns concerning the direction and magnitude of changes in synchrony, which have been attributed to biological factors. A hitherto overlooked additional explanation are differences in the currency used to quantify resource phenology, such as abundance and biomass. Studying an insectivorous bird (the sanderling) and its prey, we show that the median date of cumulative arthropod biomass occurred, on average, 6.9 days after the median date of cumulative arthropod …