Physical Sciences and Mathematics Commons^™

Multiphoton-Dressed Rydberg Excitations In A Microwave Cavity With Ultracold Rb Atoms, J. D.Massayuki Kondo, Seth T. Rittenhouse, Daniel Varela Magalhaes, Vasil Rokaj, S. I. Mistakidis, H. R. Sadeghpour, Luis Gustavo Marcassa

Physics Faculty Research & Creative Works

We investigate magneto-optical trap-loss spectroscopy of Rydberg excited Rb85 (66≤n≤68S1/2) atoms, placed inside a tailored microwave cavity. The cavity frequency at 13.053 GHz is in resonance with the 67S1/2→66P3/2 transition, inducing a ladder multiphoton microwave Rydberg absorption and emission. The observed spectra are modeled with an extended Jaynes-Cummings formalism that accounts for nonlinear multiphoton absorption from and emission into the cavity, the loss from the trap due to Rydberg excitation, and cavity imperfection. We calculate the average photons in each spectral feature and find evidence for fractional photon emission into the cavity modes within the loss spectra. The microwave cavity …

Nodal Superconductivity In Miassite Rh17s15, Hyunsoo Kim, Makariy A. Tanatar, Marcin Kończykowski, Romain Grasset, Udhara S. Kaluarachchi, Serafim Teknowijoyo, Kyuil Cho, Aashish Sapkota, John M. Wilde, Matthew J. Krogstad, Sergey L. Bud'ko, Philip M.R. Brydon, Paul C. Canfield, Ruslan Prozorov

Physics Faculty Research & Creative Works

Solid state chemistry has produced a plethora of materials with properties not found in nature. For example, high-temperature superconductivity in cuprates is drastically different from the superconductivity of naturally occurring metals and alloys and is frequently referred to as unconventional. Unconventional superconductivity is also found in other synthetic compounds, such as iron-based and heavy-fermion superconductors. Here, we report compelling evidence of unconventional nodal superconductivity in synthetic samples of Rh₁₇S₁₅ (Tc = 5.4 K), which is also found in nature as the mineral miassite. We investigated the temperature-dependent variation of the London penetration depth Δλ(T) and the disorder …

The Application Of High-Resolution Mass Spectrometry For The Analysis Of Biopolymers, Metabolites, And Biologically Relevant Small Molecules, Christ Duc Tran

Graduate Doctoral Dissertations

High-resolution mass spectrometry (HRMS), as its name suggests, possesses high resolving power that enables the separation of ions with very close mass values. This is particularly beneficial for analyzing complex samples where numerous compounds may have similar masses, as it helps prevent signal overlaps and ensures an accurate spectral analysis. The current work explores the diverse applications of high-resolution mass spectrometry in oligonucleotide research, organic synthesis and medicinal chemistry. Oligonucleotide research: Chapters 2-5 present the research results from studies that employed ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS) to understand the pharmacokinetics of RNA interference (RNAi) therapeutics. The …

A Graph Motif Adversarial Attack For Fault Detection In Power Distribution Systems, Dibaloke Chanda, Nasim Yahyasoltani

Computer Science Faculty Research and Publications

Fault detection is an integral part of the protection system in a power distribution network. Due to advanced computational capabilities, deep learning-based algorithms can significantly outperform traditional methods. However, these deep learning models are prone to adversarial attacks which are not well-addressed as traditional cyber attacks in distribution systems. More specifically, to capture the structure of distribution systems, graph neural networks (GNNs) are employed. Leveraging the backdoor attack model, we propose a novel graph-based adversarial attack algorithm for fault detection in power systems. It is further shown that the adaptable structure of GNN can make them vulnerable to adversarial attacks …

Evaluation Of 3d Beach Profiles: A New Method For Monitoring Changes In Beach Morphology And Grain Size, Kalinda Ellen Roberts

Graduate Masters Theses

Beach profiles are a simple and affordable approach to monitoring changes in beach morphology. However, traditional methods offer limited resolution and dimension. Recent advancements in technologies, particularly structure-from-motion (SfM) and grain size detection models (GSDMs), can be integrated into conventional beach profiling techniques, enabling more detailed spatial and temporal analysis of slope and grain sizes. This research introduces a new technique for coastal monitoring, termed “3D Beach Profiles,” which integrates SfM technology to create high-resolution three-dimensional digital surface models (DSMs) and orthomosaics of beach surfaces. These digital surfaces enable the extraction of beach slopes with orders of magnitude more data …

Phytoplankton Responses To Changing Irradiance And Carbon Fertilization, Alison Siersma

Graduate Theses and Dissertations (2019 - present)

Phytoplankton play a crucial role in marine ecosystems due to their innate ability to fix carbon. As atmospheric CO2 levels continue to rise from fossil fuel combustion, the resulting increase in dissolved CO2 and the concurrent decrease in ocean pH are likely to impact the phytoplankton community. The response of phytoplankton to elevated CO2 can vary significantly among species and environmental conditions (e.g. light, temperature, nutrient availability). To address these variations, an experiment was conducted using a controlled photobioreactor system, maintaining high and low light, constant temperature, nutrient levels, and two pCO2 concentrations. This study focused on two regionally relevant …

Recovery Resiliency Of Interdependent Power Systems Infrastructure Subject To Extreme Events, Partha P. Sarker

Graduate Theses and Dissertations (2019 - present)

When Hurricane Maria struck the island of Puerto Rico on September 20, 2017, it devastated the island’s aging power systems infrastructure and inflicted an island-wide power outage that left Puerto Rico in total darkness for an entire week before the system slowly started to recover. This unprecedented failure of the critical power systems infrastructure exacerbated the failure of other critical infrastructures or lifeline systems of the island. This research explores and quantifies the relationships or interdependencies that exist between the power systems and other critical infrastructure systems by investigating the post-hurricane recovery data of these lifeline systems. Subsequently, the research …

Microplastic Degradation Compared Among Dated Salton Sea Strandlines, Maria Alejandra Roman Medrano

Loma Linda University Electronic Theses, Dissertations & Projects

This thesis investigates the environmental degradation of plastic materials, with a focus on polyethylene terephthalate (PET), through a multi-phase study conducted at the Salton Sea, a closed-basin lake in a semi-arid region of California. The research addresses three core objectives: (1) developing a microplastic (MP) extraction method tailored for clay-rich sediments, (2) characterizing surface degradation of various plastic types, including PET, BoPET, HDPE, LDPE, and EPS, using advanced microscopy and spectroscopy, and (3) examining the long-term weathering of PET through samples collected from dated lake strandlines.

The extraction protocol successfully isolates MPs without oxidation, using ZnCl₂ and extended soaking to …

Synergistic Anticancer Effect Of Pistacia Lentiscus Essential Oils And 5-Fluorouracil Co-Loaded Onto Biodegradable Nanofibers Against Melanoma And Breast Cancer, Obaydah Abd Alkader Alabrahim, Hassan Mohamed El Said Azzazy

Faculty Journal Articles

Chemoresistance and severe toxicities represent major drawbacks of chemotherapy. Natural extracts, including the essential oils of Pistacia lentiscus (PLEO), exhibit substantial anticancer and anti-inflammatory activities where different cancers are reported to dramatically recess following targeting with PLEO. PLEO has promising antimicrobial, anticancer, and anti-inflammatory properties. However, the therapeutic properties of PLEO are restricted by limited stability, bioavailability, and targeting ability. PLEO nanoformulation can maximize their physicochemical and therapeutic properties, overcoming their shortcomings. Hence, PLEO was extracted and its chemical composition was determined by GC–MS. PLEO and 5-Fluorouracil (5FU) were electrospun into poly-ε-caprolactone nanofibers (PCL-NFs), of 290.71 nm to 680.95 nm …

Long-Term Push–Pull Cropping System Shifts Soil And Maize-Root Microbiome Diversity Paving Way To Resilient Farming System, Abdul A. Jalloh, Fathiya Mbarak Khamis, Abdullahi Ahmed Yusuf, Sevgan Subramanian, Daniel Munyao Mutyambai

All Peer-Reviewed Publications

Background: The soil biota consists of a complex assembly of microbial communities and other organisms that vary significantly across farming systems, impacting soil health and plant productivity. Despite its importance, there has been limited exploration of how different cropping systems influence soil and plant root microbiomes. In this study, we investigated soil physicochemical properties, along with soil and maize-root microbiomes, in an agroecological cereal-legume companion cropping system known as push–pull technology (PPT). This system has been used in agriculture for over two decades for insect-pest management, soil health improvement, and weed control in sub-Saharan Africa. We compared the results with …

Draft Final 2022 Insufficiently Reclaimed Sites Sampling Bres No. 37 – Josephine Shaft Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Biological Reinforcement Learning Simulation For Natural Enemy -Host Behavior: Exploring Deep Learning Algorithms For Population Dynamics, Komi Mensah Agboka, Emmanuel Peter, Erion Bwambale, Bonoukpoè Mawuko Sokame

All Peer-Reviewed Publications

This study introduces a simulation of biological reinforcement learning to explore the behavior of natural enemies in the presence of host pests, aiming to analyze the population dynamics between natural enemies and insect pests within an ecological context. The simulation leverages on Q-learning, a reinforcement learning algorithm, to model the decision-making processes of both parasitoids/predators and pests, thereby assessing the impact of varying parasitism and predation rates on pest population growth. Simulation parameters, such as episode count, duration in months, steps, learning rate, and discount factor, were set arbitrarily. Environmental and reward matrices, representing climatic conditions, crop availability, and the …

Phantom Jam Sybil Attack In Connected Vehicular Networks, Ahmed Ali Elamin Mohamed

Masters Theses and Doctoral Dissertations

Vehicular Ad-hoc Networks (VANETs) are vulnerable to Sybil attacks, mostly due to the lack of encryption in BSMs. In VANETs, multiple digital certificates (pseudonyms) are assigned to each vehicle to ensure their privacy. However, malicious nodes can exploit these pseudonyms to create ghost vehicles, inducing fake traffic jams and disturbance to other vehicles which may lead to accidents. In this work, we have developed the first sophisticated sybil attack, in which an attacker uses legitimate pseudonyms to create multiple ghost vehicles. These ghost vehicles transmit realistic kinematic data, using trajectory formulas and road maps. Additionally, the ghost vehicles randomly simulate …

Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon

Mechanical Engineering

This report aims to allow our sponsor, to review our design process of the Hitch Cart Landing Gear Prototype. In the design overview section of this report, we discuss the primary design modifications we made to the wheel mechanism of the existing hitch cart prototype, including the addition of the ACME screws and the folding brackets. This allows our sponsor to see the intended improvements made to the past prototype and understand the primary goal of our project. Then, in the implementation section, we cover the entire manufacturing process to allow our sponsor to understand what manufacturing steps must be …

Characterization Of Water-Soluble Inorganic Ions And Carbonaceous Aerosols In The Urban Atmosphere In Amman, Jordan, Afnan Al-Hunaiti, Zaid Bakri, Xinyang Li, Lian Duan, Asal Al-Abdallat, Andres Alastuey, Mar Viana, Sharif Arar, Tuukka Petäjä, Tareq Hussein

Michigan Tech Publications

The urban particulate matter (PM) carbonaceous and water-soluble ions were investigated in Amman, Jordan during May 2018–March 2019. The PM2.5 total carbon (TC) annual mean was 7.6 ± 3.6 μg/m3 (organic carbon (OC) 5.9 ± 2.8 μg/m3 and elemental carbon (EC) 1.7 ± 1.1 μg/m3), which was about 16.3% of the PM2.5. The PM10 TC annual mean was 8.4 ± 3.9 μg/m3 (OC 6.5 ± 3.1 μg/m3 and elemental carbon (EC) 1.9 ± 1.1 μg/m3), about 13.3% of the PM10. The PM2.5 total water-soluble ions annual mean was 7.9 ± 1.9 μg/m3 (about 16.9%), and that of the PM10 was …

Latent Characterization Of The Complete Batse Gamma-Ray Bursts Catalogue Using Gaussian Mixture Of Factor Analysers And Model-Estimated Overlap-Based Syncytial Clustering, Fan Dai, Ranjan Maitra

Michigan Tech Publications

Characterizing and distinguishing gamma-ray bursts (GRBs) has interested astronomers for many decades. While some authors have found two or three groups of GRBs by analysing only a few parameters, recent work identified five ellipsoidally shaped groups upon considering nine parameters T50, T90, F1, F2, F3, F4, P64, P256, P1024. Yet others suggest subclasses within the two or three groups found earlier. Using a mixture model of Gaussian factor analysers, we analysed 1150 GRBs, that had nine parameters observed, from the current Burst and Transient Source Experiment (BATSE) catalogue, and again established five ellipsoidal-shaped groups to describe the GRBs. These five …

Experimental Investigations Of Wind Shear From Passing A Vehicle, Hamid Rahai, Assma Begum, Jeremy Bonifacio, Ryan Moffit

Mineta Transportation Institute

Wind energy can be harnessed for various commercial and transportation-related applications. This study assessed experimentally the potential of capturing wind energy from the passage of vehicles for electric power generation. Both wind tunnel experiments and field tests were performed. The wind tunnel experiments were performed in an open-circuit low-speed wind tunnel at a free-stream mean velocity of 23 m/s. Five PVC pipes placed adjacent to the wind-blowing domain were used to simulate the columns under a freeway overpass. A scaled Ahmad body (simplified car body model) was used as the vehicle. The spanwise distance between the Ahmad body and the …

Potential Effect Of Produced Water Discharge On Surface Water: Lower Atascosa River Study, Alejandro Mendietta

Water Resources Science and Technology Theses and Graduate Research Reports (Archived)

This study investigates the potential impact of an approved produced water discharge permit in the Atascosa River. Water samples were collected from a test site on the Atascosa River and analyzed for key water quality parameters such as chloride, total dissolved solids, sodium, calcium, strontium and other ions. These results were compared to historical data from the local river authority to assess any significant changes in water quality following the permit's approval in April 2024. Statistical analyses, including averages and t-tests, were conducted to determine whether the current ion concentrations differed significantly from historical levels. While an increase in concentrations …

Detection Of Per- And Polyfluoroalkyl Substances In Public Water Supply: San Antonio Case Study, David Arambula

Water Resources Science and Technology Theses and Graduate Research Reports (Archived)

This research investigates the detection and influence of per- and polyfluoroalkyl substances (PFAS) in the San Antonio water supply system, focusing on two contaminated water entry points sourced from the Edwards Aquifer. Sampling and statistical analyses compare urbanization, geologic features, and groundwater quality between contaminated and noncontaminated sites. Key findings include statistically significant differences in fault lengths, impermeable surfaces, and urban development. Although direct correlations between PFAS contamination and groundwater quality parameters like nitrate and conductivity remain inconclusive due to limited data, the study indicates urbanization's potential role in exacerbating PFAS infiltration through sensitive geological features. Insights from this research …

Intent Visualization In Human-Agent Teams, Rahul Tushar Mehta

Theses and Dissertations

Despite advances in autonomous systems, effective collaboration between humans and intelligent agents remains a significant challenge, particularly in shared-control scenarios. This study investigates how intent visualization affects human-agent collaboration in telecollaboration scenarios, examining its impact on team performance, operator trust, and workload. Using a custom simulation environment and Wizard-of-Oz methodology, we conducted an experiment with 13 participants who completed exploration tasks under two conditions: a baseline interface and an enhanced interface with intent visualization. Results showed that while intent visualization did not significantly improve objective performance metrics, it led to a 22.6\% increase in explicit disagreements between operators and the …

Domain-Specific Machine Learning Approaches For Geospatial Problems, Shine Bedi

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation explores novel algorithms for complex geospatial problems at the intersection of environmental, social, and computational sciences. Emphasizing the unique challenges of the geospatial domain, particularly the deviation from the independent and identical distribution (IID) assumption, the research spans various methodologies across different domains, demonstrating the benefits of specialized approaches in spatial analysis.

First, we show that machine learning techniques can be effectively used in environmental modeling, which often has severe class imbalance challenges. Using artificial neural networks (ANN), support vector machines (SVM), and extreme gradient boosting (XGB) and techniques to address class imbalance provides insights into groundwater quality …

Deep Learning Vision-Based Bridge Inspection With Resource-Constrained Unmanned Aircraft Systems, Ji Young Lee

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Bridge inspection is critical for ensuring structural integrity, extending the service life of infrastructure, and minimizing maintenance costs. As bridges age and endure increasing loads, regular inspections help detect early signs of wear, such as cracks or corrosion, that could impact safety and performance. However, traditional inspection methods are labor-intensive, requiring significant time, specialized equipment, and manual access to challenging areas, which can lead to costly disruptions. Additionally, reliance on human inspectors introduces subjectivity, with assessments varying by individual expertise. These factors highlight the inefficiencies and safety risks in current inspection practices, underscoring the need for more objective, efficient solutions. …

Prevalence Of Autism Spectrum Characteristics In Students Taking Undergraduate Computing Courses, Rachel Michaela Mettenbrink

School of Computing: Dissertations, Theses, and Student Research

The incidence rate of autism spectrum condition (ASC) has increased significantly in recent decades, as awareness of the condition and its impacts increases amongst clinicians, parents, and the general population. Medical literature has proposed that there may be a relationship between ASC and participation in the computing field. This study tests for the prevalence of autism spectrum condition traits measured by delivering the Autism Spectrum Quotient (AQ) to a population of undergraduate computer science students. We examine the relationships between AQ scores and students taking undergraduate computer science classes, sex, socioeconomic status, and parents in the computing industry. Additionally, we …

Nickel Electrocatalysts On Carbon Supports For The Hydrogen Evolution Reaction., Mohan Paudel

Electronic Theses and Dissertations

Hydrogen is an important energy storage alternative to fossil fuels due to its high energy density. Currently, most hydrogen is produced through petroleum feedstocks, which produce large amounts of carbon dioxide. However, a more eco-friendly method is the electrocatalytic splitting of water into hydrogen and oxygen. Efficient catalysts for the hydrogen evolution reaction (HER) are typically platinum group metals, which are rare and expensive. There is growing interest in developing HER electrocatalysts with earth-abundant metals for water electrolysis. Nickel, which lies in the same group in the periodic table as Pt and has similar chemical properties, is explored extensively for …

Understanding Defect Dynamics In Black Phosphorene Under Noble Gas Ion Irradiation., Saransh Gupta

Electronic Theses and Dissertations

Controlled introduction of defects in phosphorene using high-energy ion beams offers a promising route to design novel high-performance materials for energy technologies. However, this potential remains underexplored due to a lack of fundamental understanding of the atomic-scale mechanisms governing the production, accumulation, and temporal evolution of defects during ion irradiation. Here, we employ a combination of classical and ab initio molecular dynamics simulations to elucidate the effects of ion energy, angle of incidence, noble gas ion size/mass, and fluence on (a) defect generation (i.e., point defects, topological imperfections, voids), (b) atomic-scale mechanisms of defect formation and re-arrangement, and (c) defect …

Computational Modeling In A Calculus-Based Physics Lab: Students’ Problems And Successes In Physics 2060, Abigail Sophia Flowers

Masters Theses

In the past few decades, computational modeling skills have become essential for students who want to pursue careers in physics or engineering. This issue of how to incorporate these skills into students' learning has become an important one because students in these degrees are already required to take several cognates outside of their chosen major. In 2018, Western Michigan University’s physics department decided to take on this issue by reformatting their introductory calculus-based physics labs to include computational modeling within the labs. The labs were first run in the Fall of 2018 and then were improved in spring 2019. When …

On Neutrosophic Pδs-Irresolute Functions In Neutrosophic Topological Spaces, Bishnupada Debnath, Anjan Mukherjee

Neutrosophic Systems with Applications

In general topology the notion of pds-irresolute and aδs-irresolute functions were introduced by Beceren and Noiri. In the present paper, these concepts of pδs-irresolute (briefly, Npδs-irresolute) and aδs-irresolute (briefly, Naδs-irresolute) functions are explored for the first time in neutrosophic topological spaces (NTS) as generalized version. We proved that every Naδs-irresolute function is Npδs-irresolute function but not conversely. Some characterizations, counter examples, and fundamental features are also presented. By neutrosophic pre-open, neutrosophic δ-open, and neutrosophic δ-semi-open sets, some new fundamental properties of such functions are provided. Furthermore, under Npδs-irresolute functions, the behavior of neutrosophic semi-connected, neutrosophic pre-connected, neutrosophic pre-T2, neutrosophic δ-semi-T2, …

Medium-Entropy Engineering Of Magnetism In Layered Antiferromagnet CuXNi2(1-X)CrXP2S6, Dinesh Upreti, Rabindra Basnet, M. M. Sharma, Santosh Karki Chhetri, Gokul Acharya, Md Rafique Un Nabi, Joshua Sakon, Mourad Benamara, Mansour Mortazavi, Jin Hu

Physics Faculty Publications and Presentations

Antiferromagnetic van der Waals-type M₂P₂X₆ compounds provide a versatile material platform for studying 2D magnetism and relevant phenomena. Establishing ferromagnetism in 2D materials is technologically valuable. Though magnetism is generally tunable via a chemical way, it is challenging to induce ferromagnetism with isovalent chalcogen and bimetallic substitutions in M₂P₂X₆. Here, we report co-substitution of Cu¹⁺ and Cr³⁺ for Ni²⁺ in Ni₂P₂S₆, creating Cu_xNi_2(1-x)Cr_xP₂S₆ medium-entropy alloys spanning a full substitution range ( …

The Model Of Norm-Regulated Responsibility For Proenvironmental Behavior In The Context Of Littering Prevention, Pengya Ai, Sonny Rosenthal

Research Collection College of Integrative Studies

Previous research suggests that descriptive norms positively influence proenvironmental behavior, including littering prevention. However, in some behavioral contexts, a weak descriptive norm may increase individuals’ feelings of responsibility by signaling a need for action. We examined this effect in the context of litter prevention by conducting structural equation modeling of survey data from 1400 Singapore residents. The results showed that descriptive norms negatively predicted ascription of responsibility and were negatively related to littering prevention behavior via ascription of responsibility and personal norms. It also showed that strong injunctive norms can reduce the inhibitory effect of descriptive norms on ascription of …

Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-Based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO₂, MoS₂, and Al₂O₃) at nanoparticles wt.% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment …