Physical Sciences and Mathematics Commons^™

Evaluation Of User Experience And Usability Of Organization Super App, Ananya Kumhan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The digital transformation of organizations in Thailand has accelerated the development of internal systems that streamline workflows and improve accessibility to organizational information. Financial institutions, which operate with multiple fragmented systems, have increasingly adopted Enterprise SuperApps as a centralized platform that combines internal services such as corporate news, leave requests, employee directories, resource information, and meeting room reservations into a single application. However, usage statistics in several organizations indicate that continuous adoption remains relatively low. Many employees rely on alternative channels or use only selected features, reflecting challenges in user experience (UX) and usability. This study aims to evaluate the …

Partial Group Divisible 3-Designs, Apiwat Peereeyaphat

Chulalongkorn University Theses and Dissertations (Chula ETD)

We introduce a generalization of group divisible 3-designs, 3-GDDs, with two groups and two indices. A partial group divisible 3-design, 3-PGDD(gı + g2, k; A, (21, 112), is an ordered pair (GrU G2, B) where G, and G2 are disjoint finite sets called groups) of size g1 and 92, respectively; and B is a collection of k-subsets (called blocks) of G, UG, such that every 3-subset of G; occurs in exactly 1 blocks in B, and every i elements of G and j elements of G2 occur together in exactly Mig blocks in B for i. i € (1,2} and …

Removal Of Antibiotics Under Visible Light By Using C,N-Tio2 Incorporated Into Magnetite Mesoporous Silica Composites, Dwita Widyawati

Chulalongkorn University Theses and Dissertations (Chula ETD)

Water contamination, particularly from antibiotics such as ciprofloxacin, is a significant environmental challenge necessitating the development of new remediation solutions. A promising technique for eliminating CIP from the environment is photocatalysis. The synthesis of C,N-doped TiO2 embedded within magnetite mesoporous silica (MSI) composites is prepared to serve as a promising semiconductor catalyst for photodegradation under visible illumination. Tetrabutyl titanate (TBOT), glucose, and urea are used as precursors in the sol-gel synthesis process, which controls elemental ratios to produce a unique mesoporous composite material intended to improve antibiotic photodegradation in the presence of visible light. Comparisons showed significant differences between capped …

Assessment Of Rainfall Anomaly In Thailand Under Enso By Inception Time For Classification Model, Hazlamee Benjawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study provides a comprehensive assessment of rainfall over Thailand during the El Niño-Southern Oscillation (ENSO) event using 41 years of monthly data (1982-2022) from meteorological stations, including total rainfall, average temperature, average wind speed, and average wind direction. The data were processed using Python by estimating spatially dependent monthly variables using inverse distance weighting. Total rainfall during ENSO events lasting more than two years was estimated by calculating ZSI12and analyzing the variable's significance using an inception time for classification model. The spatial total rainfall estimation results show that the distribution of total rainfall for normal, El Niño, and La …

Blocfog : Enhanced Transactional Data Encryption Via Fog Computing And Blockchain, Leon Wirz

Chulalongkorn University Theses and Dissertations (Chula ETD)

Protecting Personally Identifiable Information (PII) in financial transactions presents ongoing challenges, particularly in achieving a balance between strong security, fine-grained access control, and system efficiency. Existing approaches often rely on complex cryptographic operations that strain end-user devices or lack the flexibility needed for decentralized environments. Although blockchain provides advantages such as auditability and tamper resistance, its use is often limited by high computational costs and latency. This research proposes an efficient and scalable access control framework that integrates Ciphertext-Policy Attribute-Based Encryption (CP-ABE) with a lightweight fog computing layer. The system is designed to offload heavy cryptographic tasks from end users …

Improving Chinese Hate Speech Detection With Bert-Fasttext Fusion And Bert-Bilstm Fusion, Methini Ma

Chulalongkorn University Theses and Dissertations (Chula ETD)

Hate speech detection is an essential technique in the online environment, especially on social media platforms. This technique helps to create a safer space and reduce the risk of real-world harm. In Chinese, this task is particularly challenging because of unique linguistic structures and the frequent use of indirect expressions, sarcasm, homophones, character variants, and abbreviations. This study investigates how to improve Chinese hate speech detection by combining BERT with FastText and BERT with BiLSTM. There are six model variants that are configured: frozen BERT and fine-tuned BERT, each further extended with either FastText sentence embeddings or a clause-level BiLSTM. …

Gel Based Sensing Platforms For Ammonia Detection, Patita Salee

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research focuses on the development of two biopolymer-based colorimetric platforms for ammonia detection in environmental water and gaseous samples. To detect ammonia in water samples, an agarose hydrogel membrane containing salicylate, hypochlorite, and sodium nitroprusside was incorporated into a flow analysis system to perform the Berthelot reaction within the gel. Ammonium in the sample was converted to monochloramine in an alkaline reagent stream, and its subsequent interaction with the sensing membrane yielded an indosalicylate blue chromophore, causing the gel to change from pale yellow to green–blue as the ammonia concentration increased. Under the optimal operating conditions, the method provided …

Evaluation Of Soil Erosion In The Middle Yom River Basin, Passapong Paentong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aims to assess soil erosion in the Middle Yom River Basin and analyze the spatial relationships between erosion and its influencing factors using the Revised Universal Soil Loss Equation (RUSLE) in combination with Ordinary Least Squares (OLS) regression analysis. The analysis considers five principal RUSLE factors: rainfall erosivity (R), soil erodibility (K), topography (LS), cover management (C), and support practices (P), under both normal and heavy rainfall scenarios for the years 2010, 2015, and 2020. The results indicate that under normal rainfall conditions, most areas experienced low to moderate soil loss (0–5 tons/rai/year). Under heavy rainfall conditions, the …

Assessing Inter-Organizational Collaboration Within The Transboundary Network Governing The Conservation Of Southern Resident Killer Whales, Dane Pedersen, Owen Temby, Antonia Sohns, Evelyn Roozee, Gordon M. Hickey

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Southern Resident Killer Whale (SRKW) is an endangered and charismatic species whose home range spans the Salish Sea, an ecosystem that extends across the Canada-US border. Conserving and recovering the SRKW represents a high-profile transboundary governance challenge that depends heavily on collaboration between a wide range of organizations. To better understand the factors affecting transboundary SRKW governance in the Salish Sea, this study applies a multi-dimensional trust, control, perceived risk framework to assess the inter-organizational architecture supporting collaboration. The analysis is based on key informant interviews (n=32) and surveys (n=35) conducted with policy actors working for different organizations involved …

Journal Of Earth And Life Science, Academic Year 2024-2025, Megan Boche, Nathan D. Pyburn, Ben Hoover, Jayden R. Alsleben, Hector Montoya, Jr, Reed Cumberland, Rose Kuhlmann, Ray Anderson, Ellie Isakson, Seth Sisneros-Martinez, Zanden Mellen, Quady Bernu, Cian Verbridge, Benjamin D. Strei, Madelaine Adamich, Arian Garcia, Tegwen Romportl, Sandra J. Marcu, Bemidji State University

Journal of Earth and Life Science

No abstract provided.

The Relationship Between Plant Density And Microplastic Concentration In The Water In Lake Bemidji, Mn, Arian Garcia

Journal of Earth and Life Science

Microplastics, plastic particles smaller than 5 mm, are an increasing environmental threat, particularly due to their widespread distribution and toxicity. While much research has focused on larger freshwater and marine ecosystems, the presence and impacts of microplastics in smaller inland lakes remain less understood. This study investigates the relationship between plant density and microplastic concentrations in Lake Bemidji, a smaller freshwater lake. A total of 30 water samples were collected across varying vegetation conditions, ranging from open water (0%) to 90% plant coverage. Microplastics were identified and categorized into six morphological types: fibers, fragments, films, spheres/beads, and foam. The samples …

A Sample Of Fish Communities In Beaver Ponds Of Northern Minnesota, Reed Cumberland, Rose Kuhlmann

Journal of Earth and Life Science

The North American beaver Castor canadensis is an ecosystem engineer and a keystone species to the environment. Beaver inhabit ponds and construct dams to build ponds that provide habitat for certain fish. Little information is provided on the species of fish that live in beaver ponds. The objective of this study is to sample the fish communities in beaver ponds while comparing the effectiveness of two styles of minnow traps. Twelve beaver ponds were selected in the Bemidji area to be sampled. The quantity and species caught in each style of trap were recorded to compare effectiveness of each trap …

Effects Of Round-Up On The Environment, Sandra J. Marcu

Journal of Earth and Life Science

Many people around the world have used and still currently use Roundup but are unaware of the effects it has on the environment. Roundup is a spray on application weedkiller that is widely used around the world today both residentially and commercially. It enables its user to grow a garden or a field of crops with a no-tilling approach to eliminate weeds. It is a well-known and popular choice for killing weeds that has been around since the mid 1970’s (Oca, 2017). John Franz, a Monsanto scientist discovered that glyphosate (main ingredient in Roundup) was an herbicide or weedkiller, and …

The Effectiveness Of The Minnesota Buffer Law And Its Impacts On People, Ellen P. Isakson

Journal of Earth and Life Science

In January 2015, the then-governor of Minnesota Mark Dayton announced new legislation that would require 50-foot vegetation buffers along all waterways in Minnesota; this legislation would come to be known as the Minnesota buffer law, exact requirements being “perennial vegetative buffers of up to 50 feet along lakes, rivers, and streams and buffers of 16.5 feet along ditches” (Albert, 2017; MN Board of Water and Soil Resources [MN BWSR] 4 ). A buffer in the context of vegetation and natural resource management is a strip of vegetation around a body of water “designed to intercept stormwater runoff and minimize soil …

Does Depth Affect Zebra Mussel Length In Scalp Lake?, Zanden Mellen

Journal of Earth and Life Science

Since its first sighting in 1996, zebra mussels Dreissena polymorpha have been confirmed in hundreds of Minnesota lakes. Not only were they found in lakes, but they are also found in rivers too. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The objective of this study was to see if there was a relationship between a zebra mussel length and the depth, they are found using shell length (mm) and depth (cm). The comparison of zebra mussel length and depth was done by performing a …

Stars, Statutes, And Sharing: Designing Global Ip Frameworks For Space-Based Discoveries, Ed Koellner

Marquette Intellectual Property & Innovation Law Review

As humanity stretches farther into space physically, commercially, and intellectually, contemporary legal frameworks are beginning to creak under the pressure. Intellectual property laws seem to be playing catch-up. Those laws were written for a world bound by borders and gravity, not for orbital labs, the Earth’s Moon, or AI-generated inventions drifting above the Earth.

This article takes a closer look at the increasingly complex intersection of space law, intellectual property, and artificial intelligence. This domain is no longer reserved for state-led missions or high-level treaties. Now and in the near future, a university lab or a private startup might be …

Gravity And Magnetic Analysis Of The Amu Darya Basin Of Turkmenistan And Uzbekistan, Logan R. Rogers

Graduate Theses/Dissertations

The Jurassic-Tertiary Amu Darya Basin is mainly located within Turkmenistan and Uzbekistan with a small portion extending into Afghanistan and Iran. The basin is one of the largest petroleum systems in central Asia. The basin is located in the southeast corner of the Turan platform, where both the Middle Paleozoic Turkestan and Early Mesozoic Tethys oceans were closed during different orogenies. The southern boundary of the basin is along the Bande Turkestan fold belt, the Afghan-Tajik basin to the east, Paleozoic metamorphic terranes to the north, and the Karakum high (Paleozoic basement rocks) to the west. Several blocks and terranes …

Constructing Hamiltonians Using A Wannier Basis Set To Study Localized Electronic Interactions Using A Variational Quantum Eigensolver, Matthew D. Bruenning

Graduate Theses/Dissertations

In this study, I demonstrate how Wannier basis sets can be used to construct a tight binding Hamiltonian that is localized in real space. This Hamiltonian can then be studied using the Variational Quantum Eigensolver (VQE), which is able to extract the minimized energy of the system. Unlike Bloch functions, Wannier functions are localized in real space, allowing each Hamiltonian element to represent orbital overlaps between neighboring atomic orbitals. This locality enables a substantial reduction in the Hamiltonian’s size by including only the orbital projections that contribute meaningfully to localized interaction energies, such as those involved in adsorption. As a …

Modeling The Impact Of Climate Change On Plant Hardiness Zones Across The Contiguous United States Using Empirical Bayesian Kriging Regression Prediction, Daniel Donkor

Graduate Theses/Dissertations

Mapping plant hardiness zones is crucial to understanding and predicting the spatial distribution of plants in response to climatic conditions. The United States Department of Agriculture (USDA) developed the plant hardiness zones based on the average of annual extreme minimum temperatures using the Parameter elevation Regression on Independent Slope Model (PRISM). While the USDA’s 2012 and 2023 Plant Hardiness Zone maps remain standard references, they offer limited geostatistical transparency that causes more complications in replicating. This study applies Empirical Bayesian Kriging Regression Prediction (EBKRP) method to generate Plant Hardiness Zone maps, analyze spatial and temporal shifts in the plant hardiness …

Sparse Transformer For Anomaly Detection In Mobile Crowdsensing, Sanjeev Shrestha

Graduate Theses/Dissertations

Mobile Crowdsensing (MCS) is a sensing paradigm that leverages mobile devices to conduct a large-scale data collection. However, due to its openness and mobility nature, it is highly vulnerable to security issues such as injection attacks of malicious workers and fake tasks that can severely affect the platform’s normal functioning. To address this problem, the arrival of workers and task submission process is represented as a multivariate time series, and a two-stage framework is proposed. In the first step, we propose a novel transformer-based model, DozerAnomaly, that can efficiently detect anomalies in multivariate time series. We integrated a sparse attention …

Efficient Task Scheduling In Cloud Infrastructures Using Dynamic Score-Based Allocation And Deep Q-Learning, Shadman Sakib

Graduate Theses/Dissertations

Cloud computing has grown rapidly in recent years, mainly due to the sharp increase in data transferred over the internet. This growth makes task scheduling a key and challenging part of cloud systems, as it helps distribute user requests across servers to minimize response time, prevent overloading, and ensure smooth user experience. This thesis proposes two novel approaches for dynamic task scheduling in cloud environments. First, a novel Score-Based Dynamic Load Balancing (SBDLB) strategy is developed, which leverages system parameters to allocate tasks efficiently across virtual machines (VMs) in data centers. SBDLB ensures balanced workload distribution by continuously evaluating VM …

Balancing Performance And Efficiency: An Autoencoder Approach To Api-Based Malware Detection, Selma Bouraoui

Graduate Theses/Dissertations

The constant evolution of malware presents a critical challenge to today's interconnected world. It poses an increasing threat on different scales, spanning from individuals, organizations to critical infrastructures such as government’s security. Hackers continuously develop new techniques to evade detection methods. When confronted with the high volume and variety of malware, conventional approaches tend to struggle to perform in robust, accurate and timely manner. This thesis explores the application of deep learning methods to improve malware detection and classification techniques. By analyzing API call sequences, the proposed approach leverages Autoencoders to compress high-dimensional malware data into more optimized representations that …

Alpha-Synuclein Interaction With Gedunin, Tony Matundura Nyabayo

Graduate Theses/Dissertations

Parkinson’s disease (PD) and other Proteinopathies develop when α-synuclein misfolds and aggregates into toxic amyloids. While existing treatments for PD are primarily focused on managing its symptoms, a viable solution for slowing down the progress of Parkinson’s disease involves targeting the toxic α-synuclein amyloids. Gedunin, a natural inhibitor of heat shock protein 90, has been extensively used to treat malaria. Also, recent research investigations have shed light on its potential beyond malaria therapy, indicating that Gedunin may offer a possible solution for treating a variety of neurodegenerative diseases. Using plate-based assays, we examined how Gedunin influences α-synuclein fibrillation and its …

Lc-Ms Discriminates Between Effects Of Sulfur Nanoparticles Vs Molybdenum Disulfide Nanoparticles On Lettuce (Lactuca Sativa), Mary Fakunle

Graduate Theses/Dissertations

Nanotechnology is gaining attention in agriculture, majorly due to their potential benefits in farming practices. Sulfur and molybdenum disulfide nanoparticles are reported to enhance plant growth, protection, and nutrient delivery. However, there is a need to understand how nano-fertilizers affect the metabolites and nutritional benefits of plants. Here, lettuce was cultivated under greenhouse in one of three treatments: control, 50 ppm S NPs, and 20 ppm MoS2 NPs. A method was developed on Liquid Chromatography – Mass Spectrometry (LC-MS) instrument to quantify the concentration of amino acids and antioxidants in the harvested lettuce plants. Inductively Coupled Plasma – Mass Spectrometry …

Topology-Guided Adaptive Social Navigation For A Robot In Environments With Dynamic Obstacles, S.M. Faiaz Mursalin

Graduate Theses/Dissertations

Robotic navigation in dynamic environments presents significant challenges, particularly in managing interactions with moving obstacles while ensuring efficient path planning. Incorporating social navigation principles is crucial as robots share the same workspaces with humans frequently in daily life. This becomes essential for safe, efficient, and socially acceptable movements. In this thesis, I introduce a novel integration of social navigation strategies with topological path planning that leverages Discrete Morse Theory, a homotopical framework to enhance adaptability. My method dynamically assesses path feasibility and optimizes trajectory selection through three key strategies: waiting, deflection, and diverse path selection. Based on how close the …

Predicting Real Estate Prices Using Deep Learning Regression Models On Socio Spatial Data, Gentle Engworo

Graduate Theses/Dissertations

ABSTRACT

Cities keep their own kind of ledger. Every block, bus stop, corner store, and year that slips by leaves a small entry about what homes are worth. That ledger is what we call socio-spatial data: simple facts about what a home is (its age), where it sits (latitude/longitude), how easy it is to get around (distance to the nearest MRT station), what’s nearby (number of convenience stores), and when it sold (transaction date). This thesis asks a practical question in that everyday language: given these common clues, can we predict home prices more accurately and explain why? Using 414 …

Evaluation Of Practical Methods To Determine If A Karst Creek Is Gaining Or Losing: Case Study Of Leith Creek, Elizabeth Jones

Graduate Theses/Dissertations

Karst landscapes are abundant in Missouri, with features such as caves, springs, and sinkholes that form through the dissolution of limestone. Leith Creek is a small stream in Polk County, Missouri fed by two springs and the shallow unconfined Springfield Plateau aquifer, a highly karstified aquifer which is made up of limestone and minor interbedded shale-mudstone units. To determine if Leith Creek is gaining or losing, stream flow, water chemistry and temperature sensors were monitored. Stream flow results required multiple visits to take measurements while temperature sensors required two visits, one to install the dataloggers and another to remove the …

A Retrieval Augmented Approach To Improving Accuracy Of Biomedical Term Normalization By Large Language Models, Thanh Son Do

Graduate Theses/Dissertations

Ontology normalization is crucial in biomedical text processing, as it enables the mapping of medical expressions to standardized ontology terms and their corresponding identifiers. This thesis explores the feasibility of using large language models (LLMs) for ontology normalization, with a specific focus on the Human Phenotype Ontology and Gene Ontology. Prior research studies indicated that LLMs employing zero-shot learning tend to exhibit low accuracy and are prone to frequent hallucinations. We propose a retrieval augmented generation (RAG) approach to address these limitations and enhance normalization accuracy. We generated synthetic test sets of ontology-derived synonyms to evaluate normalization performance and developed …

Development Of Cyan And Blue Thermostable Fluorescent Proteins: Characterization And Structural Analysis, Acacia J. Jurkowski

Graduate Theses/Dissertations

Fluorescent proteins are commonly used as cell markers in living organisms. Modifications by mutation can be used to improve the qualities of these proteins including fluorescence, thermostability, pH stability, and chemical stability. The goal of this project is to use mutagenesis to improve the fluorescence of thermostable cyan and blue proteins derived from the thermal green protein (TGP). The first cyan protein developed by the DeVore lab (CTP 0.0) shifted the fluorescence to cyan but decreased the quantum yield (Φ_F) to 0.056. Further mutations were incorporated to increase the quantum yield through incorporating hydrogen bonding interactions to the …

Effect Of Reduction Annealing On The Structural And Electrical Properties Of Α-Moo3 Thin Films, Sandipani Ghosh

Graduate Theses/Dissertations

2D layered molybdenum oxide has attracted significant research interest due to its tuneable bandgap and diverse structural, chemical, electrical, and optical properties influenced by growth parameters and synthesis techniques. In this study, the effects of reduction annealing on the structural and electrical properties of few-layer MoO₃ thin films, deposited on Si/SiO₂ substrates via pulsed laser deposition, were investigated. X-ray diffraction revealed nanocrystalline structures with a preferred (020) orientation, reduction annealing produced highly crystalline orthorhombic α-MoO₃ with reduced unit cell volume. FESEM/EDS provided detailed analyses of microstructures and elemental compositions. Raman spectroscopy confirmed the orthorhombic structure, with characteristic peaks at 667, …