Physical Sciences and Mathematics Commons^™

Basal Topography And Carbon Accumulation Rate Of A Rare Northern California Coastal Fen, Sarah Leidinger

Cal Poly Humboldt theses and projects

Increasingly, the importance of peatlands as biodiversity hotpots, year-round water storage features, and significant carbon sinks are being recognized. Despite this, they are one of the most vulnerable ecosystems globally. While some peatland conservation and restoration initiatives are being developed, a greater understanding of small peatlands is needed to make management decisions. This study aims to determine the timing of peat formation, peat volume, and carbon accumulation rates of the Conspicuous Scoop Fen, a small (2.1-acre) fen near Bridgeville, California (~840 m.a.s.l.). During the summers of 2022 and 2023, I collected 39 m of peat cores at 14 sampling locations. …

Giving Workers The 'Green Light': Defining Green Jobs And Exploring Their Distribution In The Us, Cole Fuller

Honors Theses and Capstones

As the United States continues to adopt sustainable practices and policies to combat climate change, it is important to consider how these green changes affect the workforce. The term ‘Green Jobs’ has become the colloquial term to refer to sustainable occupations, and despite its popularity in the literature, it often has different meanings in different settings. Our first goal was to explore these definitions and establish one to contextualize our research. We used data from the Occupational Information Network, and used their green job definition, which classifies jobs as green if, and how, they are impacted by the greening economy. …

Student Attitudes And Intentions To Use Continuous Authentication Methods Applied To Mitigate Impersonation Attacks During E-Assessments, Andrea E. Green

CCE Theses and Dissertations

No solution can ultimately eliminate cheating in online courses. However, universities reserve funding for authentication systems to minimize the threat of cheating in online courses. Most higher education institutions use a combination of authentication methods to secure systems against impersonation attacks during online examinations. Authentication technologies ensure that an online course is protected from impersonation attacks. However, it is important that authentication methods secure systems against impersonation attacks with minimal disruption during an examination. Authentication methods applied to secure e-assessments against impersonation attacks may impact a student’s attitude and intentions to use the e-examination system.

In this regard, the research …

Slₖ-Tilings And Paths In ℤᵏ, Zachery T. Peterson

Theses and Dissertations--Mathematics

An SLₖ-frieze is a bi-infinite array of integers where adjacent entries satisfy a certain diamond rule. SL₂-friezes were introduced and studied by Conway and Coxeter. Later, these were generalized to infinite matrix-like structures called tilings as well as higher values of k. A recent paper by Short showed a bijection between bi-infinite paths of reduced rationals in the Farey graph and SL₂-tilings. We extend this result to higher k by constructing a bijection between SLₖ-tilings and certain pairs of bi-infinite strips of vectors in ℤᵏ called paths. The key ingredient in the proof is the relation to Plucker friezes and …

Understanding The Role Of Tacit And Explicit Knowledge Hiding In Organizations, Darren Wiggins

CCE Theses and Dissertations

Knowledge Hiding (KHi) is the deliberate act of withholding knowledge from others, driven by distrust. This distrust stems from three key factors: rationalized hiding, evasive hiding, and playing dumb. The latter two, evasive hiding and playing dumb, are particularly detrimental as they foster a cycle of mutual distrust within the workplace. To counteract this, organizations have significantly invested in promoting Tacit Knowledge (TK) and Explicit Knowledge (EK) sharing. These initiatives aimed to facilitate knowledge transfer, foster collaboration, enhance problem-solving capabilities, and strengthen social and interpersonal relationships.

Recent studies highlighted the importance of understanding the attributes linked to TK and EK. …

Empirical Assessment Of Remote Workers’ Cyberslacking And Computer Security Posture To Assess Organizational Cybersecurity Risks, Ariel Luna

CCE Theses and Dissertations

No abstract provided.

Wmu Roundtable On Port Energy Transition And Stakeholders Engagement, Aykut Ölçer, Fabio Ballini, Alessandro Schönborn, Monica Canepa, Anas Alamoush, Peyman Ghaforian, Natalia Calderón

Marener Reports

No abstract provided.

Microstructure-Based Modeling Of Primary Cilia Mechanics, Nima Mostafazadeh, Andrew Resnick, Y.-N. Young, Zhangli Peng

Physics Faculty Publications

A primary cilium, made of nine microtubule doublets enclosed in a cilium membrane, is a mechanosensing organelle that bends under an external mechanical load and sends an intracellular signal through transmembrane proteins activated by cilium bending. The nine microtubule doublets are the main load-bearing structural component, while the transmembrane proteins on the cilium membrane are the main sensing component. No distinction was made between these two components in all existing models, where the stress calculated from the structural component (nine microtubule doublets) was used to explain the sensing location, which may be totally misleading. For the first time, we developed …

Braving The Elements: Loss Of Metals From Mardi Gras Beads Due To Handling And Weathering, Thomas O. Carmichael, Ruth H. Carmichael

Gulf and Caribbean Research

The largest Mardi Gras celebrations in the U.S. are found along the Gulf of Mexico coast. With increasing awareness of and concern for environmental and human health risks due to pollution from Mardi Gras celebrations, there is a need for studies to quantify potential harms. We conducted a 2—part study to determine whether use—related handling and weathering of common Mardi Gras beaded necklaces results in loss of potentially harmful metals to the environment at levels of ecological or human health concern. Our data indicate that weathering and use—related handling can cause metals to be shed from the metallic coating of …

Revisiting The Divergent Multipole Expansion Of Atom-Surface Interactions: Hydrogen And Positronium, Α -Quartz, And Physisorption, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We revisit the derivation of multipole contributions to the atom-wall interaction previously presented in Łach et al. [G. Łach, M. DeKieviet, and U. D. Jentschura, Phys. Rev. A 81, 052507 (2010)10.1103/PhysRevA.81.052507]. A careful reconsideration of the angular momentum decomposition of the second-, third-, and fourth-rank tensors composed of the derivatives of the electric-field modes leads to a modification for the results for the quadrupole, octupole, and hexadecupole contributions to the atom-wall interaction. Asymptotic results are given for the asymptotic long-range forms of the multipole terms, in both the short-range and long-range limits. Calculations are carried out for hydrogen and positronium …

Locating Liability For Medical Ai, W. Nicholson Price Ii, I. Glenn Cohen

Articles

When medical AI systems fail, who should be responsible, and how? We argue that various features of medical AI complicate the application of existing tort doctrines and render them ineffective at creating incentives for the safe and effective use of medical AI. In addition to complexity and opacity, the problem of contextual bias, where medical AI systems vary substantially in performance from place to place, hampers traditional doctrines. We suggest instead the application of enterprise liability to hospitals—making them broadly liable for negligent injuries occurring within the hospital system—with an important caveat: hospitals must have access to the information needed …

A Bayesian Inversion For Emissions And Export Productivity Across The End-Cretaceous Boundary, Alexander A. Cox

Dartmouth College Master’s Theses

The end-Cretaceous mass extinction was marked by both the Chicxulub impact and the ongoing emplacement of the Deccan Traps flood basalt province. Both of these events perturbed the environment by the emission of climate-active volatiles, primarily CO2 and SO2. To understand the mechanism of extinction, we must disentangle the timing, duration, and intensity of volcanic and meteoritic environmental forcings. In this thesis, we used a parallel Markov chain Monte Carlo approach to invert for the aforementioned volatile emissions, export productivity, and remineralization from 67 to 65 million years ago using the LOSCAR (Long-term Ocean-atmosphere-Sediment CArbon cycle Reservoir) model. The parallel …

Nwac Snow School Intern, Nathaniel Hoang

College of the Environment Internship Reports

Mt. Baker Snow school in collaboration with the Mt. Baker Ski Area, North Cascades Institute, and the Northwest Avalanche Center (NWAC) provides an insightful opportunity for kids grades 6 – 12 to experience hands on science education and exploration at the Mt. Baker Ski area. Covering niche environmental science topics not commonly covered in typical grade school curriculum, snow school is an opportunity for children to explore different scientific implications of what they already know and how it applies to snow science. Aside from education, snow school served as an opportunity for a large majority of kids to explore a …

The Effects Of Temperature, Flooding, And Goose Feces Addition On Greenhouse Gas Emissions And Ammonification In Four High-Latitude Soils From Western Alaska, Jenna M. Ross

Electronic Theses and Dissertations

The large carbon (C) stock of wetlands is vulnerable to climate change, especially in high latitudes that are warming at a disproportional rate. Likewise, low-elevation Arctic coastal areas will flood more frequently under climate change and sea-level rise, which may alter goose herbivory and fecal deposition patterns if geese move inland. While temperature, flooding, and feces impact soil C emissions, their interactive effects have been rarely studied. Here, I explore the impact of these interactions on CO2 and CH4 emissions and nitrogen (N) mineralization (ammonification) in soils collected from four plant communities in the Yukon-Kuskokwim (Y-K) Delta, a high latitude …

Deep Adaptive Graph Clustering Via Von Mises-Fisher Distributions, Pengfei Wang, Daqing Wu, Chong Chen, Kunpeng Liu, Yanjie Fu, Jianqiang Huang, Yuanchun Zhou, Jianfeng Zhan, Xiansheng Hua

Computer Science Faculty Publications and Presentations

Graph clustering has been a hot research topic and is widely used in many fields, such as community detection in social networks. Lots of works combining auto-encoder and graph neural networks have been applied to clustering tasks by utilizing node attributes and graph structure. These works usually assumed the inherent parameters (i.e., size and variance) of different clusters in the latent embedding space are homogeneous, and hence the assigned probability is monotonous over the Euclidean distance between node embeddings and centroids. Unfortunately, this assumption usually does not hold since the size and concentration of different clusters can be quite different, …

Enhancing The Efficiency And Scalability Of Cloud Networking Systems, Jiaxin Lei

Computer Science and Engineering Dissertations

Overlay networks are the de facto network virtualization technique for providing flexible and customized connectivity among distributed containers in the cloud. Despite their widespread adoption, overlay networks incur significant overhead due to their complexity, resulting in notable performance degradation compared to physical networks.

In this dissertation, I present our three-stage solutions aimed at addressing the challenges of efficiency and scalability in cloud-based container overlay networks: Firstly, we conduct a comprehensive empirical performance study of container overlay networks, identifying crucial parallelization bottlenecks within the kernel network stack. Our observations and root cause analysis uncover that these inefficiencies primarily arise from the …

Advancing Deep Learning With Graph-Based Structural Insights: From Graph Classification To Semantic Segmentation, Xin Ma

Computer Science and Engineering Dissertations

Deep learning has profoundly transformed machine learning by offering sophisticated data representations, yet effectively incorporating structural information remains a challenge. Structural data, whether explicit or implicit, has the potential to significantly enhance the performance of deep learning tasks. This research investigates the benefits of structural information across three crucial tasks: classification, clustering, and segmentation. For explicit structural data, where inputs are directly represented as graphs, we investigate graph-level classification in brain connectivity networks. We introduce the Multi-resolution Edge Network (MENET), a novel framework designed to identify disease-specific connectomic benchmarks with high discriminatory power across diagnostic categories. MENET leverages graph-level representations …

Music Recommendation Using Exemplars And Contrastive Learning, Tina Tran

Honors Undergraduate Theses

The popularity of AI audio applications is growing, it is used in chatbots, automated voice translation, virtual assistants, and text-to-speech translation. Audio classification is crucial in today’s world with a growing need to sort and classify millions of existing audio data with increasing amounts of new data uploaded over time. In the area of classification lies the difficult and lucrative problem of music recommendation. Research in music recommendation has trended over time towards collaborative-based approaches utilizing large amounts of user data. These approaches tend to deal with the cold-start problem of insufficient data and are costly to train. We look …

Development Of Vacuum-Assisted Headspace High-Capacity Solid-Phase Microextraction For The Determination Of Semi-Volatile Compounds From Samples At Lower Temperatures, Shannon L. Thomas, Kevin A. Schug, Colton Myers, Jason S. Herrington, Reagan L. Miller, Anush Pabley, Frank W. Foss

Chemistry & Biochemistry Dissertations

Vacuum-assisted headspace solid-phase microextraction (Vac-HS-SPME) is a method used to increase solid-phase microextraction sampling of semi-volatile organic compounds. Three studies were conducted using Vac-HS-SPME via gas chromatography - mass spectrometry (GC-MS) methods for analysis of various sample types. First, a study was performed using Vac- HS-SPME combined with a high-capacity (HC) SPME Arrow to determine the operational fundamentals and workflow necessary to achieve optimal extraction of semi-volatile compounds from a model solid matrix (Ottawa sand). The fundamentals investigated included the seals necessary to create a leak-free sampling vial under vacuum conditions; the magnitude of the vacuum exerted, and the time …

Towards Machine Learning-Based Control Of Autonomous Vehicles In Solar Panel Cleaning Systems, Farima Hajiahmadi

Theses and Dissertations

This thesis presents a machine learning (ML)-based approach for the intelligent control of Autonomous Vehicles (AVs) utilized in solar panel cleaning systems, aiming to mitigate challenges arising from uncertainties, disturbances, and dynamic environments. Solar panels, predominantly situated in dedicated lands for solar energy production (e.g., agricultural solar farms), are susceptible to dust and debris accumulation, leading to diminished energy absorption. Instead of labor-intensive manual cleaning, robotic cleaners offer a viable solution. AVs equipped to transport and precisely position these cleaning robots are indispensable for efficient navigation among solar panel arrays. However, environmental obstacles (e.g., rough terrain), variations in solar panel …

Solution Combustion Synthesis And Characterization Of Fumarolic Mineral Dolerophanite, Copper (Ii) Oxide Sulfate, Eric J. Cyganowski

Chemistry & Biochemistry Theses

Dolerophanite Cu₂OSO₄ is a rare mineral found almost exclusively in the fumaroles of volcano systems and is sensitive to temperature and humidity conditions. It has a monoclinic C2/m crystal structure characterized by two-dimensional layers composed of sulfate anions dispersed amongst copper (II) oxide backbones. There has been recent interest in dolerophanite due to the magnetic properties of its Kagome-like lattice as well as its potential use as a photocatalyst or Li-ion battery electrode. Literature on the material however has been limited by the available synthesis strategies. As such, this thesis work presents a novel strategy …

Rf And Mechanical Design Of A 915 Mhz Srf Cavity For Conduction-Cooled Cryomodules, G. Ciovati, A. Castilla-Loeza, G. Cheng, J. Henry, J. Rathke, J. Vennekate, K. Harding, T. Schultheiss, J. Lewis

Physics Faculty Publications

Conduction-cooled SRF niobium cavities are being developed for use in compact, continuous-wave electron linear accelerators for a variety of industrial applications. A 915 MHz two-cell cavity has been designed to achieve an energy gain of 3.5 MeV. The design of the cell shape aims at minimizing the peak surface magnetic field. Field flatness is achieved by adjusting the length of the outer end half-cells. The higher-order mode analysis shows that absorbers are not required for a moderate beam current of 5 mA. One of the beam tubes has two side-ports for insertion of coaxial fundamental power couplers. The mechanical design …

Changes In Values And Perception Of Life: Natural Disaster Devastates A Mountain Community, Sharifullah Baig, Abida Begum

Professional Development Centre, Gilgit

The mountain communities of Karakorum and the Himalayas in Pakistan are frequently experiencing climate change-induced natural disasters, which are inflicting irreparable losses to their generation's old value system and socio-economic life. Focusing on the value system, this small-scale study explored the change in values and perceptions of a disaster-affected mountain community about natural hazards and its implications for their future lives. Twenty participants from the affected community, including local political activists, religious leaders, teachers, and youth activists, were thoroughly interviewed. The study explored significant deviations from their traditional values of connectedness to each other and with their ancestors' land. The …

Synthesis Of Hydroxycinnamate Derivatives And Characterization Of Bioactivity As Radical Scavengers And Α-Glucosidase Inhibitors, Cate Simmermaker

University of the Pacific Theses and Dissertations

Hydroxycinnamic acids (HCAs), a class of polyphenols commonly found in regularly consumed fruits and vegetables, have been investigated for efficacy as radical scavengers and glycosidase inhibitors. These compounds could mitigate the negative health effects of free radicals in oxidative stress diseases including neurodegeneration, cancer and diabetes. The HCAs investigated were caffeic acid (1), p-coumaric acid (2), ferulic acid (3), and sinapic acid (4). The compounds were derivatized with synthetically prepared amino acid esters through a four-step synthesis including protective acetylation, chlorination of the carboxylic acid, amidation, and subsequent deprotection of all applied protecting groups. The inclusion of diverse derivative groups …

The Metaverse, Religious Practice And Wellbeing: A Narrative Review, Justin Thomas, Mohammad Amin Kuhail, Fahad Albeyahi

All Works

The metaverse is touted as the next phase in the evolution of the Internet. This emerging digital ecosystem is widely conceptualized as a persistent matrix of interconnected multiuser, massively scaled online environments optimally experienced through immersive digital technologies such as virtual reality (VR). Much of the prognostication about the social implications of the metaverse center on secular activities. For example, retail, entertainment (gaming/concerts), and social networking. Little attention has been given to how the metaverse might impact religion. This narrative review explores contemporary research into online religious practice and the use of immersive digital technologies for religious purposes. This focus …

Mixed Criticality Reward-Based Systems Using Resource Reservation, Amjad Ali, Shah Zeb, Madallah Alruwaili, Asad Masood Khattak, Bashir Hayat, Ki Il Kim

All Works

Real-time systems mostly interact with the external world and each input operation must meet predetermined deadlines to be useful. However, in many real-time applications, a partial result is also acceptable. We developed a reward-based mixed criticality system based on the resource reservation approach to address the problem of ensuring the effective execution of low- and high-criticality tasks in both low- and high modes, even under heavy workloads. Using dedicated servers with pessimistic resource allocation for each high criticality task ensured their execution in both modes unaffected by low criticality tasks. The surplus resources are reclaimed and assigned to low critical …

A Multi-Objective Grey Wolf Optimizer For Energy Planning Problem In Smart Home Using Renewable Energy Systems, Sharif Naser Makhadmeh, Mohammed Azmi Al-Betar, Feras Al-Obeidat, Osama Ahmad Alomari, Ammar Kamal Abasi, Mohammad Tubishat, Zenab Elgamal, Waleed Alomoush

All Works

This paper presents the energy planning problem (EPP) as an optimization problem to find the optimal schedules to minimize energy consumption costs and demand and enhance users’ comfort levels. The grey wolf optimizer (GWO), One of the most powerful optimization methods, is adjusted and adapted to address EPP optimally and achieve its objectives efficiently. The GWO is adapted due to its high performance in addressing NP-complex hard problems like the EPP, where it contains efficient and dynamic parameters that enhance its exploration and exploitation capabilities, particularly for large search spaces. In addition, new energy and real-world resources based on solar …

Generative Ai And Large Language Models: A New Frontier In Reverse Vaccinology, Kadhim Hayawi, Sakib Shahriar, Hany Alashwal, Mohamed Adel Serhani

All Works

Reverse vaccinology is an emerging concept in the field of vaccine development as it facilitates the identification of potential vaccine candidates. Biomedical research has been revolutionized with the recent innovations in Generative Artificial Intelligence (AI) and Large Language Models (LLMs). The intersection of these two technologies is explored in this study. In this study, the impact of Generative AI and LLMs in the field of vaccinology is explored. Through a comprehensive analysis of existing research, prospective use cases, and an experimental case study, this research highlights that LLMs and Generative AI have the potential to enhance the efficiency and accuracy …

Editorial: Ethical Considerations In Electronic Data In Healthcare, Dheya Mustafa, Mousa Al-Kfairy

All Works

No abstract provided.

Hybridization Kinetics Of Four-Way Junctions Localized On A Dna Scaffold, Katherine N. Taylor

Honors Undergraduate Theses

DNA computing is an ever-growing field with scientists trying to design structures that optimize logic gate communication to develop fast, biologically compatible, computational structures. We hypothesize that by using the principles of DNA computing, it is possible to design a DNA tile capable of studying localized DNA hybridization that can differentiate between oligonucleotides of different structural conformations. This includes synthetically manipulating DNA into a nanostructure that can perform Boolean logic functions to calculate the different rates of hybridization. To test our hypothesis, we designed a DNA Tile that incorporated a 4WJ using YES logic. Linear and hairpin single-stranded (ss) DNA …