Physical Sciences and Mathematics Commons^™

Brittle-Ductile Transitions In The Kali Gandaki And Their Tectonic Significance, Ashton Brubaker

Nepal: Geoscience in the Himalaya

Brittle-ductile transitions are key sites for analyzing metamorphism in a large-scale tectonic environment. Brittle zones are ruled by Coulomb’s Law, while ductile zones with plastic deformation are explained through the Flow law. The interaction of these two zones is not a finite point, but rather a transition that accounts for a large amount of tectonic activity. These transitions indicate areas of fault zones due to variations in rock strength. The Kali Gandaki valley has not been previously observed with these brittle-ductile transitions at the forefront of the research. Outcrops in the area provide evidence of both brittle and ductile deformation …

Arkansas Corn And Grain Sorghum Research Studies 2023, Jason Kelley, Travis Faske

Arkansas Agricultural Experiment Station Research Series

The 2023 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, and insect management; economics; irrigation; agronomics; soil fertility; mycotoxins; cover crop management; and research verification program results. Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

True Contraction Decomposition And Almost Eth-Tight Bipartization For Unit-Disk Graphs, Sayan Bandyapadhyay, William Lochet, Daniel Lokshtanov, Saket Saurabh, Jie Xue

Computer Science Faculty Publications and Presentations

We prove a structural theorem for unit-disk graphs, which (roughly) states that given a set D of n unit disks inducing a unit-disk graph ...

Spatial Microsimulation Of Carbon Tax Incidence: An Application To Washington State, Nathan W. Chan, Susan Stratton Sayre

Economics: Faculty Publications

Understanding carbon tax incidence is critical. However, standard approaches for calculating the incidence of subnational policies are prone to inaccuracy due to coarse aggregation. We evaluate an alternative approach: a spatial microsimulation (SMS) method that generates granular household-level incidence estimates. SMS provides unique and more nuanced insights into the distributional consequences of carbon taxes, including across geographies. We demonstrate this method for a recent carbon tax initiative in Washington State and counterfactual variations on its revenue recycling provisions. Comparing across counterfactuals, we pinpoint how different targeting provisions in revenue recycling designs will have disparate consequences for the progressivity/regressivity of the …

Explainable Artificial Intelligence: Methods And Evaluation, Gayane Grigoryan

Engineering Management & Systems Engineering Theses & Dissertations

A wide array of techniques within explainable artificial intelligence (XAI) have been developed to measure the importance of features in machine learning models. A notable portion of these methods draws upon principles of cooperative game theory (CGT), with the Shapley value emerging as a widely used solution concept. Despite the rising prominence of the Shapley value, other promising solutions from cooperative game theory—such as the Nucleolus, Banzhaf power index, Shapley-Shubik power index, and solutions to conflicting claims problems—have been comparatively overlooked, even though they hold significant potential. In this dissertation, multiple XAI methods based on these other CGT solutions are …

On Weighted Sequence Spaces, Gilbert D. Acheampong

Mathematics & Statistics Theses & Dissertations

The space ℓ^p,α of complex sequences a = (a₀,a₁,a₂, . . .) for which

∞

∥a∥p,α = ( Σ|ak|^p(k+1)^α)^1/p < ∞

k=0

is studied. Each such sequence can be identified with the analytic function with power series

∞

f (z) = ∑ akz^k.

k=0

In this setting, the point evaluation and the difference quotient mappings are shown to be bounded; the cases are identified in which ℓ^p,α is boundedly contained in ℓ^r,β . …

Synthesis And Characterization Of Cobalt-Based Complexes And Metal-Organic Frameworks For Hydrogen Evolution Catalysis Under Acidic Conditions, Elizabeth A. Tonsel-White

Chemistry & Biochemistry Theses & Dissertations

The synthesis of two cobalt(II) complexes: the novel complex [Co(phen)₃]₂[Co(pytc)₂]•16.25H₂O 1 and the previously reported [Co(bpy)₃](OH)₂•7H₂O 2, along with a cobalt(II/III)-containing MOF, Co-PPF2, previously reported as well, was achieved. These complexes were characterized by elemental analysis, X-ray crystallography, microscopy, conductivity measurements, TGA, SEM, CV , and UV-visible , and FTIR spectroscopies. From the CV scan rates, diffusion coefficients for complexes 1 and 2 were determined to be 1.0 × 10⁻⁶ cm² s⁻¹ and 4.8 × 10⁻⁷ cm² s⁻¹. Electrocatalytic studies with complexes 1 and 2 revealed insights into the mechanistic aspects of …

Deep Learning In Reproducing Kernel Banach Spaces, Mingsong Yan

Mathematics & Statistics Theses & Dissertations

Deep learning has achieved immense success in the past decade. The goal of this dissertation is to understand deep learning through the framework of reproducing kernel Banach spaces (RKBSs), which were originally proposed for promoting sparse solutions. We begin by considering learning problems in a general functional setting, and establishing explicit and data-dependent representer theorems for both minimal norm interpolation (MNI) problems and regularization problems. These theorems provide a crucial foundation for the subsequent results derived for both sparse learning and deep learning. Next, we investigate the essential properties of RKBSs capable of encouraging sparsity in learning solutions. With the …

Raemap: Real-Time Advanced Eye Movements Analysis Pipeline, Gavindya Jayawardena

Computer Science Theses & Dissertations

Eye-tracking offers insights into human cognition and attention allocation by capturing and interpreting eye movements. Traditionally, eye tracking research has relied on offline analysis methods, requiring post-experiment processing to derive insights from gaze data. This approach limits its applicability in contexts requiring immediate feedback and adaptive responses based on real-time gaze behaviors. Recent advancements in computing power and eye tracking technology have enabled a shift towards real-time analysis, allowing modern systems to interpret gaze data with minimal latency, facilitating integration into interactive applications and experiments. Despite these advancements, existing tools often face challenges with real-time computation of advanced gaze measures …

Who Wrote The Scientific News? Improving The Discernibility Of Llms To Human-Written Scientific News, Dominik Soós

Computer Science Theses & Dissertations

Large Language Models (LLMs) have rapidly advanced the field of Natural Language Processing and become powerful tools for generating and evaluating scientific text. Although LLMs have demonstrated promising as evaluators for certain text generation tasks, there is still a gap until they are used as reliable text evaluators for general purposes. In this thesis project, I attempted to fill this gap by examining the discernibility of LLMs from human-written and LLM-generated scientific news. This research demonstrated that although it was relatively straightforward for humans to discern scientific news written by humans from scientific news generated by GPT-3.5 using basic prompts, …

Investigation Of Cooperative Subradiance In Dense Ultracold Rubidium Ensembles, Brent Michael Jones

Physics Theses & Dissertations

This dissertation presents results of an experimental investigation of the time resolved fluorescence from a cold and dense ensemble of ⁸⁷Rb atoms after the sample is illuminated by a short probe pulse. The goal of the experiment was to investigate cooperative subradiant behavior, characterized by a much longer decay time compared to the natural lifetime, induced in an off resonant probe regime. Such long lived states, if controllable, would provide a means to store quantum information. The samples were initially created in a magnetooptical trap before atoms were loaded into a far off resonance trap to achieve atomic densities …

Privacy-Preserving Deep Learning Framework For Iot Malware Detection, Sabbir Ahmed Khan

Computer Science Theses & Dissertations

Cyberattacks on IoT devices are accelerating at an unprecedented rate, largely driven by IoT malware activities. The IoT malware attacks typically comprise three stages: intrusion, infection, and monetization. Existing IoT malware detection methods fail to identify malicious activities at the intrusion and infection stages and thus cannot stop potential attacks timely. In our research, we have leveraged power side-channel information as input to our deep learning model to identify malware at early stages of intrusion on IoT devices. But, deploying a resource-intensive deep learning model on highly resource-constrained IoT devices is a significant challenge. Consequently, utilizing a Machine Learning as …

Surfacing Text Changes In Archived Webpages, Lesley Frew

Computer Science Theses & Dissertations

Webpages change over time, and web archives hold copies of historical versions of webpages. Users of web archives, such as journalists, want to find and view changes on webpages over time. However, the current search interfaces for web archives do not adequately support this task. For the web archives that include a full-text search feature, multiple versions of the same webpage that match the search query are shown individually without enumerating changes, or are grouped together in a way that hides changes. We present a change text search engine that allows users to find changes in webpages. We describe the …

Mesostructure Reconstruction Of Prepreg Platelet Molded Composite With Artificial Intelligence, Richard Larson

Mechanical & Aerospace Engineering Theses & Dissertations

Prepreg platelet molded composites (PPMC) are long, discontinuous fiber reinforced polymer materials. PPMC are an important subcategory of composite materials as they are processible into geometrically complex structures and can be produced via high-throughput manufacturing processes, however they have higher stiffness and strength as compared to traditional discontinuous fiber reinforced polymers. However, there is inherent randomness in the structure of PPMCs and as such, PPMC parts frequently require per part testing that is cost prohibitive.

Herein, a method using artificial intelligence is proposed as a more cost-effective method of inspecting PPMC parts. Different artificial intelligence (AI) architectures are explored to …

Harnessing Social Media For Disaster Response: Intelligent Identification Of Reliable Rescue Requests During Hurricanes, Wael Khallouli

Engineering Management & Systems Engineering Theses & Dissertations

Hurricanes pose a significant threat to both human lives and infrastructure. Decision-makers face substantial challenges during such events, as they must act quickly to address victims’ needs. Social media platforms provide a valuable source for quick and real-time information. Recent hurricane events have shown that people turn to social media to call for help when official communication channels, such as 911, are overwhelmed. However, extracting actionable information from the massive number of messages posted on social media is challenging. Furthermore, verifying social media messages posted by the public is a critical concern for disaster response practitioners, making them hesitant to …

Study Of Atypical Alarmone Synthesis In Clostridioides Difficile, Declan Nathaniel Butler

Chemistry & Biochemistry Theses & Dissertations

Clostridioides difficile is a Gram-positive anaerobic bacterium that causes infections in humans that costs healthcare systems billions per year. C. difficile infection has high rates of recurrence due to multiple antibiotic resistance. When bacteria are in stressful environments, they produce hyperphosphorylated guanosine ribonucleotide signaling molecules called alarmones. The accumulation of alarmones activates the stringent response (SR), in which bacterial cells induce transcription of stress survival genes to delay growth and replication. The C. difficile SR is regulated by enzymatic activity of a bifunctional synthetase/hydrolase, RelA/SpoT homolog (RSH), and a monofunctional small alarmone synthetase (RelQ). Additionally, the SR is potentially regulated …

Enhancing The Security In High-Speed Networks Using P4 Programmable Switches, Ali Alsabeh

Theses and Dissertations

Network security has become increasingly essential in today's networks due to the growth of various network applications, such as Machine Learning (ML) and Fifth-Generation (5G) Networks. One fundamental Internet protocol is the Domain Name System (DNS), which maps domain names to Internet Protocol (IP) addresses. Despite its importance, DNS traffic is often forwarded without being analyzed, making it a center of ever-evolving attacks. Traditionally, defense strategies are implemented on fixed-function security middleboxes that are costly, proprietary, and hard to manage. Alternatively, defenses implemented in software use general-purpose servers (e.g., the control plane of a Software-Defined Networking (SDN) network) that cannot …

Offshore Detachment Of The Winyah Bay Plume Through Ekman Dynamics Under Upwelling Conditions, Isabella Moore

Theses and Dissertations

ABSTRACT River plumes play a crucial role in coastal ecosystems by influencing land-ocean interactions, primary production, water quality, and ocean circulation. This study presents observations of a buoyant river plume off Winyah Bay, South Carolina (USA), conducted in 2020 and 2021. Observations comprised CTD casts and shipborne ADCP profiles as well as near surface flow measurements from a floating platform and microstructure profiles in uprising mode. This research focuses on the offshore transport of the buoyant water through Ekman dynamics under upwelling-favorable conditions. Under varying wind forcing and stratification scenarios, the Winyah Bay plume either remains near the coast or …

Dual Light Emission Of Cssni3-Based Powders Synthesized Via A Mechanochemical Process, Xuan Huang, Xiaobing Tang, Xiyu Wen, Yuebin Charles Lu, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

Lead toxicity has hindered the wide applications of lead halide perovskites in optoelec- tronics and bioimaging. A significant amount of effort has been made to synthesize lead-free halide perovskites as alternatives to lead halide perovskites. In this work, we demonstrate the feasibility of synthesizing CsSnI3-based powders mechanochemically with dual light emissions under ambi- ent conditions from CsI and SnI2 powders. The formed CsSnI3-based powders are divided into CsSnI3-dominated powders and CsSnI3-contained powders. Under the excitation of ultraviolet light of 365 nm in wavelength, the CsSnI3-dominated powders emit green light with a wavelength centered at 540 nm, and the CsSnI3-contained powders …

Pressure Dependence Of The Rate Coefficient Of Ozone Using Master Equation Simulations Of Recombination Kinetics, Adil Yermek

Master's Theses (2009 -)

The ozone layer in Earth’s atmosphere is distinctive and crucial for the evolution of life. Investigating the process of ozone formation aids in comprehending the evolution of our planet’s atmosphere. The reaction that forms ozone is O + O2 → O3. One can describe ozone forming reaction approximately using Lindeman mechanism, which is very handy. However, its limitation arises from assuming a steady-state approximation, which neglects transient dynamics and complexities that could impact reaction kinetics under non-equilibrium conditions. For this reason, Master Equation simulations can be seen as an enhancement or extension of the Lindemann mechanism, providing a thorough understanding …

Theoretical And Experimental Evaluation Of The Electronic Relaxation Mechanisms Of 2-Pyrimidinone: The Primary Uva Absorbing Moiety Of The Dna And Rna (6–4) Photolesion, Sean J. Hoehn, Sarah E. Krul, Carlos E. Crespo-Hernández

Faculty Scholarship

The (6–4) photolesion is a key photodamage that occurs when two adjacent pyrimidine bases in a DNA strand bond together. To better understand how the absorption of UVB and UVA radiation by the 2-pyrimidinone moiety in a (6–4) lesion can damage DNA, it is important to study the electronic deactivation mechanism of its 2-pyrimidinone chromophore. This study employs theoretical (MS-CASPT2/cc-pVDZ level) and experimental (steady state and femtosecond broadband spectroscopic) methods to elucidate the photochemical relaxation mechanisms of 2-(1H)-pyrimidinone and 1-methyl-2-(1H)-pyrimidinone in aqueous solution (pH 7.4). In short, excitation at 320 nm leads to the population of the S1¹(ππ*) …

Cognitive Technologies, Tom Davenport

Asian Management Insights

AI and the revolution of work.

Professor Tom Davenport, the President’s Distinguished Professor of Information Technology and Management at Babson College, speaks about how companies can integrate generative Artificial Intelligence (GenAI) into their operations while ensuring workforce adaptation and skills development.

Development Of An Algorithm To Identify And Calculate The Amount Of File Slack On An Image Of A Given Drive, Nicholas Flynn

Honors Theses

As society increasingly relies on technology, the rates of cyber crime have been increasing at exponential rates. Cyber criminals are also discovering new ways to hide evidence of their crimes. This study develops a forensic analysis algorithm to evaluate the amount of file slack on an image of a drive. Slack space, leftover drive space on a disk sector after a file has been written, can be exploited to hide data. The algorithm aims to detect and calculate this slack space to help direct forensic investigations. The algorithm was evaluated on a population dataset of 100,000 files with random data …

Poly(Thioether) Thermosets With Gated Photodegradation, Surabhi Jha

Dissertations

Photodegradable polymer networks are attractive due to the precise spatiotemporal control and large-area applicability of light. Chemical linkages that enable these polymer networks to be photo-responsive, also hinder their applicability in ambient light. Photostable and photodegradable networks have recently been reported to overcome this challenge by combining other stimuli with light for degradation. We report the design of a network that responds to a simultaneous, dual stimulus for photodegradation. We design poly(thioether acetal) networks with benzylidene acetal moieties that are known to undergo β-scission in the presence of free thiols. By blocking these free thiols with a thermally labile protecting …

Crosssections, Summer 2024, University Of Northern Iowa. Department Of Physics.

CrossSections

Contents:

A Message from the Department Head, Dr. Paul Shand --- 01
New Secretary --- 02
Homecoming Picnic --- 03
Visits to the Department --- 04
Awards Banquet --- 05
Begeman Lecture --- 05
Physics Competition --- 06
Holiday Colloquium --- 06
Tim Kidd Lecture --- 07
Faculty Profile - Larry Escalada --- 07
Student Profile - Ashley Harrington --- 08
Student Research - Haley Harms --- 10
Physics Scholarships and Awards --- 12
Teacher Education Transformation --- 13
Alumni Profile - Justin Bohnet --- 14
Alumni News - Corey Cooling --- 15
Alumni News - John Bolte --- 16 …

Establishment Of Protocols To Measure Near-Ir(Nir) Surface-Enhanced Raman Scattering (Sers) Signals Of Nir Dye, Justin B. Ramsey

Forensic Science Master's Projects

Biomedical imaging techniques are crucial for early disease diagnostics, particularly for life-threatening conditions. However, traditional methods have inherent limitations, such as restricted spatial resolution and potential risks associated with repeated exposure to ionizing radiation. Near-infrared (NIR) surface-enhanced Raman spectroscopy (SERS) presents a promising alternative due to its minimal risks and potential for high-resolution biomedical imaging. A key challenge in NIR-SERS biomedical imaging is the development of biocompatible, nontoxic SERS substrates that can be safely introduced into the human body, targeting specific cells and tissues effectively.

NIR-SERS substrates typically consist of gold nanoparticles (AuNPs) modified with biorecognition elements and reporter molecules, …

The Analysis Of Artificially Flavored Coffees, Hannah Knights

Longwood Senior Thesis Proposal

This project aims to determine the molecular components that give artificially flavored coffees their advertised flavor. Much work has been conducted to determine various characteristics such as antioxidant properties, phenolic compounds, flavors, and aromas found in natural coffees. In addition, there is ample literature on the results of sensory tests for a variety of commercial coffees. However, not much work has been conducted to determine the compounds found in artificially flavored coffees that give rise to their distinctive aroma and flavor. This is, perhaps, due to the proprietary nature of the flavoring process employed by commercial producers. The goal of …

Green Finance Growth Prediction Model Based On Time-Series Conditional Generative Adversarial Networks, Aya Salama Abdelhady, Nadia Dahmani, Lobna M. Abouel-Magd, Ashraf Darwish, Aboul Ella Hassanien

All Works

Climate change mitigation necessitates increased investment in green sectors. This study proposes a methodology to predict green finance growth across various countries, aiming to encourage such investments. Our approach leverages time-series Conditional Generative Adversarial Networks (CT-GANs) for data augmentation and Nonlinear Autoregressive Neural Networks (NARNNs) for prediction. The green finance growth predicting model was applied to datasets collected from forty countries across five continents. The Augmented Dickey-Fuller (ADF) test confirmed the non-stationary nature of the data, supporting the use of Nonlinear Autoregressive Neural Networks (NARNNs). CT-GANs were then employed to augment the data for improved prediction accuracy. Results demonstrate the …

A Comparison Of Structure, Bonding And Non-Covalent Interactions Of Aryl Halide And Diarylhalonium Halogen-Bond Donors, Nicole Javaly, Theresa M. Mccormick, David R. Stuart

Chemistry Faculty Publications and Presentations

Halogen bonding permeates many areas of chemistry. A wide range of halogen-bond donors including neutral, cationic, monovalent, and hypervalent have been developed and studied. In this work we used density functional theory (DFT), natural bond orbital (NBO) theory, and quantum theory of atoms in molecules (QTAIM) to analyze aryl halogen-bond donors that are neutral, cationic, monovalent and hypervalent and in each series we include the halogens Cl, Br, I, and At. Within this diverse set of halogen-bond donors, we have found trends that relate halogen bond length with the van der Waals radii of the halogen and the non-covalent or …

Toward Untangling Thunderstorm-Aerosol Relationships: An Observational Study Of Regions Centered On Washington, Dc And Kansas City, Mo, Mace Bentley, Tobias Gerken, Zhoujun Duan, Dudley Bonsal, Henry Way, Endre Szakal, Mia Pham, Hunter Donaldson, Lucie Griffith

School of Integrated Sciences - Faculty Scholarship

A multi-variable investigation of thunderstorm environments in two distinct geographic regions is conducted to assess the aerosol and thermodynamic environments surrounding thunderstorm initiation. 12-years of cloud-to-ground (CG) lightning flash data are used to reconstruct thunderstorms occurring in a 225 km radius centered on the Washington, D·C. and Kansas City Metropolitan Regions. A total of 196,836 and 310,209 thunderstorms were identified for Washington, D.C. and Kansas City, MO, respectively. Hourly meteorological and aerosol data were then merged with the thunderstorm event database.

Evidence suggests, warm season thunderstorm environments in benign synoptic conditions are considerably different in thermodynamics, aerosol properties, and aerosol …