Digital Commons Network^™

Development Of P-Type Cesium Iodide Thin Film For Radiation Detection By Rf-Magnetron Sputtering, Rhett Simon Tabbada

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cesium iodide (CsI) is a wide-bandgap alkali halide semiconductor with strong potential for radiation detection and optoelectronic integration, though its intrinsic insulating nature limits charge transport. In this study, the effects of silicon (Si) doping on the structural, optical, electrical, and radiation-response capabilities as a semiconductor of CsI thin films were determined. The CsI thin films were deposited on n-Silicon (n-Si) (100) substrates using magnetron sputtering. In the optimization of sputtering conditions, three films with a thickness of 250 nm were fabricated with varying sputtering power for Si: 0W, 5W, and 10W, while keeping the sputtering power for CsI constant …

Endoplanar: Deformable Planar-Based Gaussian Splatting For Surgical Scene Reconstruction, Thatphum Paonim

Chulalongkorn University Theses and Dissertations (Chula ETD)

Precise modeling of deformable anatomical structures from stereoscopic endoscopic footage plays a critical role in advancing surgical guidance and robotic automation within image-assisted medical procedures. Recent advances in Gaussian splatting have demonstrated real-time visualization capabilities with notable quality on endoscopic data; however, traditional 3D Gaussian representations introduce volumetric artifacts that compromise geometric fidelity and depth accuracy. We address these challenges through EndoPlanar, a deformable planar Gaussian framework that projects volumetric primitives onto planar surfaces. This planar formulation facilitates bias-free depth calculation and normal vector derivation—capabilities that remain elusive with standard ellipsoidal representations. We further incorporate a regularization mechanism to ensure …

Advancing Voice Spoofing Detection In Thai : A Comprehensive Dataset And Performance Analysis On Speaking Styles And Channel Effects, Ticho Urai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Voice authentication is increasingly used in applications such as banking and call center verification, but it faces serious risks from spoofed voices. Recent advances in text-to-speech (TTS) and voice cloning make it possible to generate highly natural fake speech, creating an urgent need for robust anti-spoofing systems. While most prior work focuses on English, little research addresses the Thai language. To fill this gap, we present the Chula Spoofed Speech (CSS) dataset, a large-scale Thai corpus containing 1.3M utterances of both bona fide and synthetic speech. The synthetic samples are generated using five state-of-the-art TTS systems from the same utterances …

Bismuth Surfactant-Mediated Epitaxy Of Gaas(Bi) On On-Axis Ge(100) Substrates, Valgeir Sigmarsson

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, Bi-surfactant-mediated epitaxy is applied in GaAs(Bi) film deposition on nom- inally on-axis Ge(100) substrates to investigate its effect on mitigating the formation of anti-phase domains (APDs) inherent to the polar-on-non-polar GaAs/Ge(100) heterostructure. GaAs(Bi) layers were deposited by solid-source molecular beam epitaxy (MBE) with a V/III ratio of ~90 and stepwise variations in Bi flux between samples. The Bi-free GaAs sample exhibited an unstable RHEED pattern indicating ill-ordered growth mode, confirmed by AFM showing an amor- phous surface with an RMS value of ~20 nm. In contrast, Bi-assisted growth produced stable RHEED (1×3) surface reconstructions. AFM revealed single-crystal …

Risk Management For Irrigation Water Pumping Project In Myin Gyan District, Myanmar, Ye Lin Aung

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study evaluates risk and performance management in the Si Mee Khon irrigation water pumping project in Myin Gyan District, Myanmar. Although intended to supply irrigation to 5,000 acres of farmland, the project has fallen short of planned targets. By Q3 2025, 53.62% of the budget had been spent while only 44% of the intended coverage had been completed, signalling significant delays and cost inefficiencies. The research identifies and prioritises key risks, assesses their effects on schedule and cost performance, and proposes mitigation strategies. A mixed-method approach was used, combining interviews with twenty MOALI officials and quantitative analysis based on …

Characterization And Leaching Feasibility Studies Of Copper Flue Dust For The Recovery Of Main And Trace Metals, Fardis Nakhaei, Marek Locmelis, Lana Alagha, Michael S. Moats, Carlos Eyzaguirre, Cory Smith

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Although copper smelter dust (CSD) is classified as hazardous waste, it also serves as a valuable secondary resource, offering potential for the recovery of critical elements. In this study, CSD samples were collected from the waste heat boiler (WHB) and electrostatic precipitator (ESP) units connected to the flash smelting furnace at a copper smelter. The representative samples were extensively characterized by particle size, and chemical and mineralogical analyses. Following sample characterization, leaching experiments were performed to evaluate the potential extraction of Cu, Fe, As, Zn, Pb, In, Ga, and Ge from the flue dusts. Distilled water, H2SO4, and HCl were …

Designing Robust Quasi-2d Perovskites Thin Films For Stable Light-Emitting Applications, Sharmistha Khan, Reshna Shrestha, Mengru Jin, Doyun Kim, Guan Lin Chen, Ruipeng Li, Yijia Gu, Qing Tu, Namyoung Ahn, Wanyi Nie

Materials Science and Engineering Faculty Research & Creative Works

Quasi-2D perovskite made with organic spacers co-crystallized with inorganic cesium lead bromide inorganics is demonstrated for near unity photoluminescence quantum yield at room temperature. However, light emitting diodes made with quasi-2D perovskites rapidly degrade which remains a major bottleneck in this field. In this work, It is shown that the bright emission originates from finely tuned multi-component 2D nano-crystalline phases that are thermodynamically unstable. The bright emission is extremely sensitive to external stimuli and the emission quickly dims away upon heating. After a detailed analysis of their optical and morphological properties, the degradation is attributed to 2D phase redistribution associated …

Representation Learning Of Point Cloud Data For Process Mining And Anomaly Detection In Complex Systems, Yujing Yang

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Complex systems, e.g., advanced manufacturing systems, are largely associated with dynamic and transient behaviors, resulting in condition changes and anomalies. Sensor-based condition monitoring is critical in detecting anomalies and supporting process monitoring and performance improvement for complex manufacturing systems. Traditional sensor-based monitoring approaches primarily focus on one-dimensional (1D) signals and two-dimensional (2D) images, which are limited in their ability to capture high-resolution spatial patterns pertaining to anomalies induced by systems’ condition changes, especially subtle ones. Recent advancements in three-dimensional (3D) sensing present a unique opportunity to address this limitation by enabling the capture of 3D point cloud data with micro-level …

Enhancing Risk And Crisis Communication With Computational Methods: A Systematic Literature Review, Madison H. Munro, Ross J. Gore, Christopher J. Lynch, Yvette D. Hastings, Ann Marie Reinhold

VMASC Publications

Recent developments in risk and crisis communication (RCC) research combine social science theory and data science tools to construct effective risk messages efficiently. However, current systematic literature reviews (SLRs) on RCC primarily focus on computationally assessing message efficacy as opposed to message efficiency. We conduct an SLR to highlight any current computational methods that improve message construction efficacy and efficiency. We found that most RCC research focuses on using theoretical frameworks and computational methods to analyze or classify message elements that improve efficacy. For improving message efficiency, computational and manual methods are only used in message classification. Specifying the computational …

A Systematic Literature Review On Resilient Digital Transformation, Examining How Organizations Sustain Digital Capabilities, Thira Chavarnakul, Li Da Xu, Zhuming Bi, Achyut Shankar, Gaurav Dhiman, Wattana Viriyasitavat, Danupol Hoonsopon

Information Technology & Decision Sciences Faculty Publications

In an era marked by relentless technological shifts and market volatility, digital transformation (DT) alone is insufficient. Organizations must develop Resilient Digital Transformation (RDT)—the organizational capabilities required to sustain DT over a medium-term horizon—to navigate these challenges effectively. This study primarily aims to propose a guideline for fostering RDT. Drawing on the PRISMA guidelines and a systematic review of 77 peer-reviewed papers, this study identifies and synthesizes key targets and drivers across three core pillars: Technology, Organization, and External Environment. These elements collectively foster organizational resilience. Specifically, this study highlights how adaptability, innovation, and scalability form the technological underpinnings of …

Emerging Nanotechnology Approaches For Blood Disorders: A Comprehensive Review Of Nano-Hematinics And Plant-Based Nanomedicines, Hassan Abdulsalam Adewuyi, Khairat Shamsudeen, Fatima Mahmoud Muhammad, Adeola Kolawole Victor, Sakariyau Adio Waheed, Adepeju Matilda Adekoya, Kashim Ibrahim Muhammad, Blessing Temitayo Longe, Abdulgaffar Abdulquddus

Chemistry & Biochemistry Faculty Publications

Background: Disorders affecting blood components, such as anemia, coagulopathies, and hematologic malignancies, continue to pose significant global health burdens. Traditional therapies often fall short due to adverse effects, limited bioavailability, and insufficient targeting of disease sites.

Objective: This review synthesizes current advances in nano-hematinics and plant-based nanomedicines (phyto-nanomedicines) as innovative strategies for managing blood-related conditions. These nanoscale interventions are designed to enhance therapeutic precision, bioactivity, and safety.

Methods: A systematic review was conducted using major scientific databases including PubMed, Scopus, Web of Science, and ScienceDirect. Search terms were carefully selected to retrieve literature published between 2015 and 2024 that discussed …

Study Of Deep Neural Network Trained With Salient, Compressed Medical Video Data For Enhanced Predication, Aileen Sengupta

Electrical Engineering Dissertations - Archive

The rapid growth of surgical video analysis presents a need for efficient deep learning models for surgical training, while reducing the need for excessive image and video image storage. Traditional training approaches typically rely on uniformly compressed video data, instead of selectively preserving the most surgically relevant regions. This dissertation investigates the impact of training deep neural networks (DNNs), both convolutional and transformer-based architectures, on saliency-guided, differentially compressed surgical video sequences. The study systematically evaluates how such compression influences prediction accuracy, computational efficiency and storage requirements. Experimental results demonstrate that models trained on ROI-focused compressed data combined with motion vectors …

Correlation Of Internal Pressure To The Fundamental Aging Mechanism Of Li-Ion Batteries, Kayla Garcia

Electrical Engineering Theses - Archive

As technology continues to evolve, the demand for more reliable and longer-lasting batteries is growing rapidly in the electronics industry. Batteries are vital for powering a wide range of technologies, from smartphones and consumer electronics to automotive systems and high-end tools used across multiple sectors. Lithium-ion batteries (LIBs) have helped bridge the power and energy gap that these different technologies require while achieving sufficient efficiency and reliability to make carrying them around feasible and long lasting. To further enhance the performance and longevity of a these devices, a deeper understanding of the degradation mechanisms occurring inside LIBs is crucial. The …

Coastal Flooding Along The Lower Brazos During The Landfall Of Hurricane Beryl -A Model-Based Investigation, Sabiha Tasnuva Khan

Civil Engineering Theses - Archive

Hurricane Beryl generated a complex hydrodynamic response along the Texas coast and Lower Brazos River, producing storm surge, elevated coastal water levels, intense rainfall, and widespread inundation. Low-gradient coastal rivers such as the lower portion of the Brazos River are particularly sensitive to the interaction of these drivers, yet the inland decay of surge energy and its interplay with watershed runoff remain poorly quantified. This study aims to characterize the physical mechanisms controlling water-level amplification, flow reversal, surge attenuation, and inundation development during Hurricane Beryl along the Lower Brazos and to determine the relative contributions of surge and rainfall to …

Advancing Wind Turbine Blade Longevity Through Innovative Trailing Edge Reinforcement Using Auxetic Tpu Structures, Gianluca Provvisiero

Open Access Master's Theses

The trailing edge of wind turbine blades represents one of the most failure prone regions due to local buckling phenomena and repeated mechanical stresses. This thesis explores a specific reinforcement strategy aimed at extending blade longevity by integrating Re-entrant honeycomb structures made of thermoplastic polyurethane (TPU) within the trailing edge. By numerically identifying and targeting high stress zones, the insertion of lightweight auxetic TPU foam enhances local stiffness and mitigates premature failure without compromising aerodynamic performance. Finite Element Analysis (FEA) simulations demonstrate the effectiveness of this approach when compared to blades models without any internal reinforcement. The methodology of this …

Earthquake Wrangler: Leveraging Ios Technology For Earthquake Detection And Early Warning Application To Enhance Public Safety., Luis F. Salome

Theses and Dissertations--Civil Engineering

Earthquakes are devastating natural phenomena and generate secondary hazards such as tsunamis, landslides and fires. Their catastrophic impacts span both developed nations including the United States, Japan, Turkey, and Italy and developing countries such as El Salvador, Haiti, Nepal and the Philippines, where disparities in early warning infrastructure remain important. Seismic events start with stress waves generated by tectonic plate motion, with body waves (P- waves and S-waves) and surface Rayleigh and love waves that carry energy through the earth. While some regions have adopted advanced early warning systems based on seismic hazard models and strong ground motion analysis, others …

Engineering A Novel Solvent Regenerator That Leverages Electrochemically Induced Ph Swings For Direct Air Capture And Hydrogen Generation, Emmanuel Aluhunmile Ohiomoba

Theses and Dissertations--Mechanical and Aerospace Engineering

Direct Air Capture (DAC) is considered to be a key component for achieving global net-negative emissions. However, to capture CO₂ at the low concentrations in the atmosphere requires materials with high affinity for CO₂. This makes the solvent-based chemical approach for DAC more applicable compared to physical approaches. Nonetheless, regenerating the capture solvent presents a significant challenge due to high heat requirements for thermal decomposition of carbonates. Leveraging electrochemical principles provides an opportunity to simplify the regeneration process, thus, this work focuses on engineering an electrochemical solvent regenerator for recovering alkaline solvents for DAC, with co-production of …

Damping Modulation Of Dampened Kapton Surfaces, Sebastian Esteban

Honors Undergraduate Theses

When droplets are vibrated or disturbed, they can exhibit a complex sloshing motion, an understudied behavior in drop physics. Droplet sloshing involves a complex combination of transverse and longitudinal motion that changes the droplet's effective weight on the surface the droplet is on. Our current understanding stems from preliminary work focusing on a cantilever beam of fixed thickness and variable viscosity of the liquid being sloshed. This investigation will focus on how variable cantilever thickness and constant viscosity for a liquid being sloshed affects the beam's deflection under consistent vibration. It will also investigate how the natural frequency of a …

Integrated Compliant Structure For A Hand Exoskeleton, Tristan R. Koopman

Honors Undergraduate Theses

This thesis presents the design and prototyping of a wearable hand exoskeleton that integrates a flexible structural framework to assist with hand movement while maintaining comfort and anatomical conformity. The goal was to create a device that supports tendon-driven actuation through a compliant structure, combining elements of rigidity and flexibility to match the natural geometry and motion of the human hand. Traditional hand exoskeletons often trade off motion for structure or vice versa. This project aims to bridge that gap with a hybrid compliant design that balances flexibility and support. The design process followed an iterative approach involving rapid prototyping …

Fabricating Silver-Ceria Polymer Nanocomposite Scaffolds For Biomedical Therapeutic Applications, Shreya S. Pawar

Honors Undergraduate Theses

Improper healing of bone fractures and limited regeneration of bone following bone tumor resection remain a prevalent complication worldwide. Long-term effects of this include joint instability, limited movement, and arthritis. Bone infections (osteomyelitis), reactive oxygen species (ROS) generation via excessive inflammation, and underlying conditions such as osteoporosis can contribute to suboptimal bone tissue regeneration. ROS accumulation stimulates osteoblast apoptosis, while promoting osteoclast differentiation. These processes inhibit mineralization and osteogenesis. Conventional therapeutics involve the utilization of drugs and bone grafts. However, these approaches pose limitations and can result in subsequent complications. Microbial infections, ROS accumulation, and excessive inflammations are factors that …

Ai-Generated Messaging For Life Events Using Structured Prompts: A Comparative Study Of Gpt With Human Experts And Machine Learning, Christopher Lynch, Erik Jensen, Ross Gore, Virginia Zamponi, Kevin O'Brien, Brandon Feldhaus, Katherine Smith, Joseph Martínez, Madison H. Munro, Timur E. Ozkose, Tugce B. Gundogdu, Ann Marie Reinhold, Hamdi Kavak, Barry Ezell

VMASC Publications

Large Language Models (LLMs) play an increasingly integrated and pivotal role in generating diverse types of texts, such as social media messages, emails, narratives, and technical reports, among other textual communication forms. As AI-generated messaging filters into human communication, a systematic exploration of their effectiveness for mimicking human-like communication of life events is needed. In this study, we employ a zero-shot structured narrative prompt to generate 24,000 life event messages for birth, death, hiring, and firing events using OpenAI's GPT-4. From this dataset, we manually classify 2880 messages and evaluate their validity in conveying these life events through the form …

Facial Chick Sexing: An Automated Chick Sexing System From Chick Facial Image, Marta Veganzones Rodriguez, Thinh Phan, Arthur F.A. Fernandes, Vivian Breen, Jesus Arango, Michael T. Kidd, Ngan Le

Computer Science and Computer Engineering Faculty Publications and Presentations

Chick sexing, the process of determining the gender of day-old chicks, is a critical task in the poultry industry due to the distinct roles that each gender plays in production. While effective traditional methods achieve high accuracy, color, and wing feather sexing is exclusive to specific breeds, and vent sexing is invasive and requires trained experts. To address these challenges, we propose a novel approach inspired by facial gender classification techniques in humans: facial chick sexing. This new method does not require expert knowledge and aims to reduce training time while enhancing animal welfare by minimizing chick manipulation. We develop …

Estimation Of Energy Use Intensity By Space Usage At Minnesota State University, Mankato, Rocio Alvarado Ramirez

All Graduate Theses, Dissertations, and Other Capstone Projects

This thesis creates a model that serves as an evaluation tool for testing decarbonization strategies on energy-related projects at Minnesota State University, Mankato, by estimating Energy Use Intensity for different types of spaces across campus. These EUIs can be used to predict future energy consumption when space usage changes and also serve as a baseline for dynamic energy modeling. The methodology used was a regression-based spreadsheet model proposed by Dr. Shreshth N. and originally applied at the Massachusetts Institute of Technology. EUIs were estimated across five different scenarios, and for electricity, steam, and chilled water. Three criteria were used to …

Wearable Lanyard Acc For On-Demand Communication, Valerie Rosario, Rileigh Kearney, Hailey Soares, Kristen Martinez, Hannah Pereira

Student Research Design & Innovation Symposium

Augmentative and Alternative Communication (AAC) devices help individuals experiencing challenges with verbal communication, including English language learners, individuals who are hard of hearing, on the autism spectrum, or those experiencing anxiety disorders. Current technologies include low-tech communication boards and complex mobile applications, but both of these offer little customization. Our prototypes integrate touch-sensing panels and small LCD screens into common wearables, like necklaces and lanyards, so that the ACC discretely blends in with everyday apparel and provides on-demand communication that is customizable to the individual user. The touch-sensing pads are sensory-friendly, and the LCD screens operate without sound to support …

Citizen-Centric Building Energy Retrofits: Understanding And Supporting Citizens As Occupants, Participants, Decision-Makers, And Learners In Home Energy Retrofits, Nikhil Singh Yaduvanshi

Civil Engineering Dissertations - Archive

Residential building retrofits remain significantly under-adopted despite substantial technological advances, economic incentives, and policy efforts, creating a critical gap between technical potential and actual implementation in achieving climate goals. Assessment of citizen involvement in building retrofit processes plays a critical role in formulating effective home retrofit program designs to ensure maximum adoption rates and avoid energy waste. Although, existing retrofit programs and decision-making models recognize the importance of citizen involvement, the extent of citizen capabilities and the effects of citizen-centered approaches on retrofit adoption and building performance has not been comprehensively examined. The adoption and success of retrofit programs depends …

Assessment Of The Feasibility Of Utilizing Plastic Waste In Infrastructure To Promote Circular Economy In Bangladesh, Md Lutfor Rahman

Civil Engineering Dissertations - Archive

This study presents a comprehensive assessment of municipal solid waste (MSW) and plastic waste characterization across Bangladesh, with a focus on circular economy opportunities and the long-term economic viability of plastic road. Using on-site waste characterization data for 13 major cities from four geographic zones of Bangladesh —Northwest, Northeast, Southwest, and Southeast—the research identifies food waste as the dominant component of the national waste stream (67.3%), followed by plastic (12.4%), textiles (7.8%), and paper (4.7%). Among plastics, low-density polyethylene (LDPE) overwhelmingly dominates (89.7%), highlighting the continued prevalence of single-use flexible plastics.

A life cycle cost analysis (LCCA) was conducted comparing …

Implementation And Performance Evaluation Of Plastic Road Mix Design In Parking Lot, Ishraq Faruk

Civil Engineering Dissertations - Archive

The uncontrolled proliferation of plastic waste has emerged as a global environmental crisis, with high-density polyethylene (HDPE) constituting a substantial fraction of the waste stream due to its extensive use in packaging and its resistance to degradation. In parallel, asphalt pavements particularly in urban infrastructure such as parking lots experience accelerated deterioration from raveling, rutting, and cracking as a result of thermal cycling, repetitive loading, and inadequate drainage. These converging challenges present an opportunity for innovative, circular-economy-based sustainable pavement technologies that simultaneously improve surface durability and mitigate plastic waste accumulation.

This research investigates the full-scale implementation and monitoring of HDPE …

Leveraging Transformer-Based Ocr Model With Generative Data Augmentation For Engineering Document Recognition, Wael Khallouli, Mohammad Shahab Uddin, Andres Sousa-Poza, Jiang Li, Samuel Kovacic

Engineering Management & Systems Engineering Faculty Publications

The long-standing practice of document-based engineering has resulted in the accumulation of a large number of engineering documents across various industries. Engineering documents, such as 2D drawings, continue to play a significant role in exchanging information and sharing knowledge across multiple engineering processes. However, these documents are often stored in non-digitized formats, such as paper and portable document format (PDF) files, making automation difficult. As digital engineering transforms processes in many industries, digitizing engineering documents presents a crucial challenge that requires advanced methods. This research addresses the problem of automatically extracting textual content from non-digitized legacy engineering documents. We introduced …

Online Parameter Adaptation Of Lqr Controllers Via Rls For Prosthetic Joint Control: Experimental Validation On A Quanser Qube-Servo 2 Platform, Cynthia Lopez-Jordan

Theses and Dissertations

This thesis develops and experimentally validates an online adaptive Linear Quadratic Regulator (LQR) control method for prosthetic joint systems using Recursive Least Squares (RLS)-based real-time parameter estimation on the Quanser QUBE-Servo 2 platform. Traditional LQR controllers assume a fxed system model, which limits adaptability and results in reduced tracking accuracy, poor robustness, and loss of optimal performance when applied to dynamically changing prosthetic joints, infuenced by load variations, user gait changes, and mechanical wear. Limited experimental validation exists for combining RLS with online LQR adaptation in prosthetic-like systems.

To address these limitations, an RLS-driven Adaptive LQR framework was implemented to …

Development Of A Spss-Based Prediction Model To Evaluate ‎Volatile Organic Compounds During Trenchless Cured-In-Place Pipe Method, Salar Bavili Nezhad

Civil Engineering Dissertations - Archive

The Cured-in-Place Pipe (CIPP) method is a widely implemented trenchless technology for the rehabilitation of deteriorated pipelines, offering benefits such as cost-effectiveness and reduced surface disruption. However, the CIPP installation process, particularly during curing, raises concerns over the emission of Volatile Organic Compounds (VOCs), which can adversely impact worker safety, public health, and environmental standards. This dissertation aims to address these concerns by evaluating VOC emissions during CIPP installations and developing a predictive model to guide emission management practices.

A comprehensive field study was conducted, collecting air samples from 15 pipeline rehabilitation sites that utilized different site-specific conditions using non-Styrene …