Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Physical Sciences and Mathematics (1876)
- Medicine and Health Sciences (1605)
- Engineering (1297)
- Social and Behavioral Sciences (859)
- Chemistry (670)
-
- Computer Sciences (618)
- Education (457)
- Chemical Engineering (429)
- Arts and Humanities (314)
- Architecture (295)
- Life Sciences (292)
- Medical Sciences (256)
- Computer Engineering (236)
- Public Health (222)
- Dentistry (214)
- Nursing (214)
- Communication (207)
- Communication Technology and New Media (207)
- Mass Communication (207)
- Polymer Chemistry (203)
- Environmental Sciences (200)
- Sports Sciences (199)
- Sociology (193)
- Civil and Environmental Engineering (184)
- Pharmacy and Pharmaceutical Sciences (181)
- Business (175)
- Economics (174)
- Urban, Community and Regional Planning (169)
- Mathematics (161)
- Health and Physical Education (145)
Articles 31 - 60 of 6951
Full-Text Articles in Entire DC Network
Occlusal Analysis Using A Novel Classification Of Static And Dynamic Articulations In Tmd And Non-Tmd Patients, Uthai Uma
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background: Temporomandibular disorders (TMD) are multifactorial conditions affecting masticatory systems. While occlusal morphology has been suggested as a contributing factor, functional, behavioral, and postural elements may play a more prominent role. This study aimed to evaluate demographic, clinical, occlusal, and functional characteristics associated with TMD in a Thai patient population using a novel articulation classification. Methods: A retrospective analysis of 872 participants (684 TMD, 188 non-TMD) was conducted. Data included demographic characteristics, postural and habitual behaviors, occlusal morphology, articulation classification, articulation ratios, mandibular range of motion, and TMD diagnostic categories. The articulation classification and ratios were designed and tested for …
Rational Decision-Making Model: Ap Micro, Ar Macro, A-Level Economics, And Ib Economics, Nasiwat Thanathitiphuwaphat
Rational Decision-Making Model: Ap Micro, Ar Macro, A-Level Economics, And Ib Economics, Nasiwat Thanathitiphuwaphat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Should students take high school economics? They face choices among Advanced Placement (AP), Advanced Level (AL), and International Baccalaureate (IB) Economics programs, which are equivalent to college-level economics coursework. While students value their initial exposure to economics, whether high school economics provides optimal utility remains uncertain. We employ a rational decision-making model to guide students in choosing an appropriate economics education. We emphasize the importance of achieving high grade, as AP, AL, or IB Economics can enhance college admission prospects, improve the economics learning experience, and allow for credit transfer. Students must first identify exam availability and financial constraints before …
Wage Gap And Wage Discrimination Among Persons With Disabilities: Empirical Evidence From Thailand, Natthavit Wongsrithanasarn
Wage Gap And Wage Discrimination Among Persons With Disabilities: Empirical Evidence From Thailand, Natthavit Wongsrithanasarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study provides a comprehensive quantitative analysis of the disability wage gap and potential wage discrimination in Thailand. Utilizing data from the 2017 and 2022 Thailand Disability Surveys, this research employs the Oaxaca-Blinder decomposition technique to examine wage disparities between workers with and without physical or cognitive disabilities. The results reveal a substantial wage gap, with non-disabled workers, on average, earning approximately 50% more than persons with physical disabilities and more than twice as much as persons with cognitive disabilities. The decomposition analysis indicates that while over 75% of the wage gap for persons with physical disabilities is explained by …
Academic Management Strategies For Public Universities In Henan Province, People’S Republic Of China To Enhance The Digital Literacy, Jiepei Jin
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to 1) study the conceptual framework of public university academic management and the digital literacy. 2) analyze strengths, weaknesses, opportunities, and threats of academic management of public universities in Henan province, China to enhance the digital literacy. 3) develop academic management strategies for public universities in Henan province, China to enhance the digital literacy. A multi-phase mixed methods research design was employed integrating both quantitative and qualitative approaches. The sample consisted of 38 universities in Henan Province, People’s Republic of China. The informants were university administrators and faculty members. The instruments used for data collection included questionnaire, …
Academic Management Strategies Of Private High Schools In Zhejiang, China Based On The Concept Of Digital Entrepreneurship, Jingmei Ma
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aimed to achieve three research objectives: 1) To study the conceptual frameworks of academic management of private high schools and digital entrepreneurship competencies; 2) To identify the strengths, weaknesses, opportunities, and threats (SWOT) of academic management in Zhejiang private high schools based on the concept of digital entrepreneurship; 3) To develop academic management strategies for Zhejiang private high schools to enhance students’ digital entrepreneurship competencies. A multiphase mixed-methods research design was adopted, integrating quantitative and qualitative approaches. The informants included teachers and administrators from private high schools in Zhejiang Province, with a total of 627 respondents. Research instruments …
Automated Infinite Combos Detection System For Collectible Card Game, Amornpong Trakarnkulphun
Automated Infinite Combos Detection System For Collectible Card Game, Amornpong Trakarnkulphun
Chulalongkorn University Theses and Dissertations (Chula ETD)
In Collectible Card Games, resources management is one of the most effective strategy. However, there are some combinations of cards which produce unlimited resources called infinite combos. Too-cheap infinite combos that can be played early in the game break game environment, because the player who executes the combo immediately wins. To solve the problem, game designers usually restrict a part of the combos from being played. Due to the large number of cards in the card pool, it is difficult to search for these combos and solve this problem before a release date of a card set. This research aims …
Effect Of Solvent On Nonanoic And Azelaic Acids Yield Enhancement From Oxidative Cleavage Of Oleic Acid, Chakreeya Santhadklang
Effect Of Solvent On Nonanoic And Azelaic Acids Yield Enhancement From Oxidative Cleavage Of Oleic Acid, Chakreeya Santhadklang
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates the effect of solvent choice on the oxidative cleavage of oleic acid using hydrogen peroxide (H2O2) as the oxidant, with a focus on improving the yields of nonanoic acid (NA) and azelaic acid (AA). Solvent selection was found to play a critical role due to polarity differences between the reactants and oxidants. tert-Butanol was unsuitable because of its low boiling point, leading to the evaluation of higher-boiling solvents including guaiacol, acetoin, ethyl lactate, and isobutyric acid. Guaiacol and acetoin exhibited undesirable chemical reactivity, while ethyl lactate resulted in low yields due to hydrogen bonding with intermediate species. …
Experimental Investigation Of Surfactant Impact On Surfactant-Oil-Brine System For Surfactant Enhanced Oil Recovery, Chananpat Worpattanaluk
Experimental Investigation Of Surfactant Impact On Surfactant-Oil-Brine System For Surfactant Enhanced Oil Recovery, Chananpat Worpattanaluk
Chulalongkorn University Theses and Dissertations (Chula ETD)
Enhanced Oil Recovery (EOR) is a vital technique for improving hydrocarbon extraction efficiency from mature or low-production reservoirs. Among various EOR methods, chemical flooding, particularly surfactant-based EOR, has gained attention due to its ability to reduce interfacial tension (IFT), to alter rock wettability, and to mobilize trapped oil. However, the performance of surfactant systems is highly sensitive to reservoir salinity, temperature, and rock-fluid interactions, leading to surfactant precipitation, adsorption losses, and interfacial tension reduction. Therefore, understanding the effects of salinity, surfactant concentration, and the role of scale inhibitors on the physicochemical stability of surfactant-oil-brine systems is essential for designing robust …
Pipeline For Non-Self-Intersecting Racetrack Generation In Racing Games, Chatrtime Chatramornrat
Pipeline For Non-Self-Intersecting Racetrack Generation In Racing Games, Chatrtime Chatramornrat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Procedural content generation (PCG) allows racing games to supply new racetracks automatically, but straightforward generators can produce layouts with unrealistically tight bends or self-crossings that compromise playability. This thesis introduces a racetrack generation pipeline that connects chain–code–based synthesis with a dedicated post-processing stage for resolving intersections. Candidate layouts are first assembled from image–based differential chain codes and adjusted so that each forms a closed loop. Regions where the centreline crosses itself are then identified and repaired by cutting and joining overlapping branches and applying locally constrained smoothing, so that the overall course geometry is kept intact. Finally, geometric descriptors such …
Efficient Photocatalytic Hydrogen Evolution Via Novel Syntheses Of Srtio₃/G-C₃N₄ Heterojunction Photocatalysts, Chiramet Thatsanakunlaphan
Efficient Photocatalytic Hydrogen Evolution Via Novel Syntheses Of Srtio₃/G-C₃N₄ Heterojunction Photocatalysts, Chiramet Thatsanakunlaphan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Strontium titanate/graphitic carbon nitride (SrTiO3/g-C3N4) heterojunctions are widely used as photocatalysts. However, traditional multistep synthesis methods for these photocatalysts often involve complexity, long processing times, and high energy consumption. To address these issues, a systematic comparison of various simplified synthesis approaches was conducted, emphasizing the influence of synthesis parameters on the structural properties and hydrogen evolution performance. Six comparative studies were conducted to illustrate the roles of solvent choice, thermal post-treatment, and synthesis route. Results showed that ethylene glycol consistently produced more active photocatalysts than ethanol in both one-pot and two-step solvothermal methods. Non-calcined samples exhibited superior hydrogen evolution activity …
Gitcofl : Design And Implementation Of A Git-Based Federated Learning Framework Utilizing Container-Based Technology, Chokchai Faroongsarng
Gitcofl : Design And Implementation Of A Git-Based Federated Learning Framework Utilizing Container-Based Technology, Chokchai Faroongsarng
Chulalongkorn University Theses and Dissertations (Chula ETD)
The rapid proliferation of artificial intelligence (AI) necessitates training paradigms that are both robust and privacy-preserving. Traditional centralized federated learning (CFL) suffers from single points of failure and communication bottlenecks, while decentralized federated learning (DFL) introduces communication complexities and lacks integrated version control. This paper proposes GitCoFL, a novel framework that leverages Docker containers and a Git server as an independent, external medium for model weight communication and storage. This architecture provides inherent flexibility, enabling efficient operation in both CFL and DFL settings. Using CIFAR-10 benchmarks with MobileNet and using FedAvg for federation algorithms, GitCoFL achieves competitive F1 score when …
Quality Of Life Prediction For Driving Route Planning System Using Image Recognition And Deep Learning, Intouch Prakaisak
Quality Of Life Prediction For Driving Route Planning System Using Image Recognition And Deep Learning, Intouch Prakaisak
Chulalongkorn University Theses and Dissertations (Chula ETD)
Assessing travel-related Quality of Life (QoL) is a significant challenge due to its reliance on subjective human perception, which is difficult to measure. Traditional studies are often constrained by the limited scope of costly, manual data collection. The significant contribution of this research is the introduction of a new framework that can analyze tourist perception on a large and systematic scale. The novelty of this work lies in the utilization of Google Street View (GSV) as a large-scale visual data source, coupled with the use of a sequence-based model to analyze travel routes, which allows for the simulation of the …
A Benchmarking Study Of Grover's Algorithm For Solving Boolean Sat With Quantum Circuits, Jirapas Unison Jipipob
A Benchmarking Study Of Grover's Algorithm For Solving Boolean Sat With Quantum Circuits, Jirapas Unison Jipipob
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study explores how well Grover's Algorithm performs in solving the Boolean Satisfiability Problem (SAT) using quantum circuits. The algorithm is implemented with IBM's Qiskit framework and compared to classical brute-force methods. Experiments focus on 3-SAT, 4-SAT, and 5-SAT problems, using quantum simulators and IBM quantum hardware. The results show that Grover's Algorithm is more efficient, offering a theoretical quadratic speedup over classical methods. However, practical issues like limited qubit availability, hardware noise, and optimization challenges impact its current performance. The data highlights the potential for quantum computing to scale and solve NP-complete problems. This research shows how quantum computing …
Out-Of-Domain Tuberculosis Detection From Chest X-Ray Images Using Meta Learning With Soft Labels, Kanokphat Jinanarong
Out-Of-Domain Tuberculosis Detection From Chest X-Ray Images Using Meta Learning With Soft Labels, Kanokphat Jinanarong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Automated tuberculosis screening from chest x-ray images could greatly benefit regions with limited medical resources. However, currently available methods could not handle this problem well due to the difference in chest x-ray images in each region caused by the difference in machine and demographics, the possible noise in the available labels, and other reasons. We therefore propose a new machine learning algorithm that could detect tuberculosis with great accuracy on any other data sources by learning from completely different data sources. We used a model-agnostic meta-learning together with a soft label approach, utilizing the meta-gradient to dynamically adjust the soft …
A Study On The Impact Of Superconducting Fault Current Limiteron Arc Flash Hazard In An Industrial System, Kittipong Anantanasap
A Study On The Impact Of Superconducting Fault Current Limiteron Arc Flash Hazard In An Industrial System, Kittipong Anantanasap
Chulalongkorn University Theses and Dissertations (Chula ETD)
The increasing integration of distributed generation raises short-circuit current levels, which lead to concerns about equipment overheating, insulation deterioration, and system stability issues. The Resistive Superconducting Fault Current Limiter (R-SCFCL) offers an effective solution by dynamically increasing circuit impedance during faults without affecting normal operation. However, its integration may alter the fault-clearing time of the protection system, which is crucial for arc-flash safety. This study evaluates the impact of R-SCFCL integration on arc-flash hazards in an industrial power system, utilizing DIgSILENT PowerFactory and calculations based on IEEE 1584. Results indicate that while the R-SCFCL effectively reduces arcing current, the incident …
Feasibility Study Of Utilization Of Calcium-Based Material For Integrated Methane Dry Reforming And Co2 Absorption-Mineralization Processes, Nattanan Watcharasawat
Feasibility Study Of Utilization Of Calcium-Based Material For Integrated Methane Dry Reforming And Co2 Absorption-Mineralization Processes, Nattanan Watcharasawat
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis investigates an integrated absorption-mineralization and dry reforming of methane (IAM-DRM) loop. The aim is to demonstrate the feasibility of using CaCO3 derived from amine scrubbing both as a CO2 sink and as reactive support for in situ Ni activation during DRM, while simultaneously regenerating the MEA solvent and calcium material for repeated use. CO2 absorption of monoethanolamine (MEA) yield equilibrium loadings of 0.66 mol CO2 mol-1 MEA with regenerated MEA maintaining identical performance. Mineralization on CaCl2 and Ca(OH)2 produced different phases product. Temperature programmed DRM demonstrated that mineralized CaCO3 can activate Ni in situ and sustain CH4 conversion. …
Enhancing Large Language Models For Legal Question Answering : A Case Study On The Land And Building Tax Act In Thailand, Nattapat Tantapong
Enhancing Large Language Models For Legal Question Answering : A Case Study On The Land And Building Tax Act In Thailand, Nattapat Tantapong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Thailand's Land and Buildings Tax Act requires interpreting multiple legal instruments. However, general-purpose large language models often produce answers that lack both accuracy and verifiable legal citations, which are essential for legal reasoning. This study investigates whether curriculum-structured fine-tuning enables small Thai-aligned models (8B parameters) to perform comparably to large commercial models. The research constructs a domain-specific corpus of 8,410 Q&A pairs with 30,612 hard-negative triplets, then evaluates four curriculum designs and four adapter ranks using retrieval completeness and answer quality metrics. The experimental results reveal two key findings. First, hard-negative retrieval training improves Multi-HitRate@5 by 2.6% and Multi-MRR@5 by …
Effect Of Catalyst Bed Configuration On Temperature Profile And Reactor Performance For Fischer-Tropsch Synthesis : A Computational Fluid Dynamics Simulation, Natthasit Khawyen
Effect Of Catalyst Bed Configuration On Temperature Profile And Reactor Performance For Fischer-Tropsch Synthesis : A Computational Fluid Dynamics Simulation, Natthasit Khawyen
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigates the performance of the Fischer–Tropsch reaction in a fixed-bed reactor packed with spiral-structured catalysts using COMSOL Multiphysics to evaluate heat management, hot spot reduction, and the enhancement of high-value product selectivity. The study comprises two main scenarios. The first examines the effects of tube spacing and number of tubes in a multitube reactor arranged in a hexagonal pattern using a 20% Co/SiO₂ spiral-structured catalyst. In models R1–R4, which contain a fixed number of 10 tubes, tube spacing was found to have only a limited influence on temperature distribution; all models still exhibited a hot spot near the …
Performance Evaluation Of Strategic Bandwidth Block Assignment For Interference Reduction In High-Density 5g Nr Cell Environments, Pasapong Wongprasert
Performance Evaluation Of Strategic Bandwidth Block Assignment For Interference Reduction In High-Density 5g Nr Cell Environments, Pasapong Wongprasert
Chulalongkorn University Theses and Dissertations (Chula ETD)
Due to the increasing demand for mobile data, mobile network operators (MNOs) typically rely on cell densification to increase capacity. However, doing so also introduces more inter-cell interference (ICI), leading to lower spectral efficiency and making further capacity enhancements challenging. This thesis explores a bandwidth block assignment method for ICI mitigation. The core idea is to divide the bandwidth of an NR carrier into two partially overlapping bandwidth parts (BWPs) to reduce the impact of ICI. By allowing the two BWPs to share the same synchronization signal block (SSB), the same attach and handover configurations can be applied. A modified …
Behavior Of Reinforced Concrete Beams With Externally Anchored Rebars, Nyan Soe Lynn
Behavior Of Reinforced Concrete Beams With Externally Anchored Rebars, Nyan Soe Lynn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates a minimally invasive rehabilitation method for reinforced concrete (RC) beams using externally anchored reinforcement by means of epoxy. Two programs were conducted: flexural rehabilitation using externally anchored longitudinal bars, and shear rehabilitation using externally anchored U-shaped stirrups. Four beam specimens were tested under four-point bending for the flexural program, and four under three-point bending for the shear program. Test results from the flexural program showed large deformation due to plastic hinge formation. Due to their unbonded nature, the external rebars engaged later than the internal reinforcement and developed large deflection. Load-carrying capacity, however, was not increased since …
Tailoring The Intrinsic Properties Of Polypropylene/Polypropylene Carbonate Blends Using Epoxidized Natural Rubber As A Bio-Based Compatibilizer, Patsita Suphansomboon
Tailoring The Intrinsic Properties Of Polypropylene/Polypropylene Carbonate Blends Using Epoxidized Natural Rubber As A Bio-Based Compatibilizer, Patsita Suphansomboon
Chulalongkorn University Theses and Dissertations (Chula ETD)
The goal of this study was to enhance the biocompatibility of polypropylene/polypropylene carbonate (PP/PP) polymer blends by varying amounts of epoxidized natural rubber (ENR). This study focuses on determining how ENR concentration affects the interface and final properties of the polymer blend. A comprehensive analysis of the physical, mechanical, thermal, chemical, and dynamic mechanical properties, as well as the rheological properties of the PP/PPC system, was conducted to assess structural changes and property evolution within the PP/PPC system. The experimental results revealed that ENR can interact with PPC, resulting in a reduced domain size and a more uniform distribution. This …
Diffusion Model-Based Synthetic Image Augmentation For Enhancing Vehicle Detection Model Performance, Pawaris Parnphotong
Diffusion Model-Based Synthetic Image Augmentation For Enhancing Vehicle Detection Model Performance, Pawaris Parnphotong
Chulalongkorn University Theses and Dissertations (Chula ETD)
A critical challenge for modern object detection models is the significant performance degradation encountered in adverse weather or poor lighting conditions. This issue primarily stems from the imbalance of training datasets, which are predominantly composed of normal daytime scenes, resulting in reduced robustness when models face challenging scenarios. Although traditional data augmentation techniques exist, they are limited to pixel-level adjustments and inherently restricted in generating data diversity. Consequently, this research proposes an approach utilizing diffusion models to generate realistic synthetic images that simulate new atmospheric and environmental conditions. To maximize the efficiency of synthetic data generation, we investigated a crucial …
Development Of Self-Healing Polymer From Bio-Based Benzoxazine Blend With Poly(Ethylene Glycol) For Anti-Biofouling Applications, Pharaporn Yodkum
Development Of Self-Healing Polymer From Bio-Based Benzoxazine Blend With Poly(Ethylene Glycol) For Anti-Biofouling Applications, Pharaporn Yodkum
Chulalongkorn University Theses and Dissertations (Chula ETD)
Biofouling remains a significant challenge in marine industries, as conventional coatings often lose their antifouling efficacy once they become damaged. Incorporating self-healing capabilities into antifouling coatings has therefore emerged as a promising strategy to extend service life and maintain long-term performance. In this study, self-healing polymers were developed based on a bio-derived benzoxazine resin (E-fa), synthesized from renewable precursors including eugenol (a phenol source), furfurylamine (an amine source), and paraformaldehyde, and subsequently blended with poly(ethylene glycol) (PEG). The blends were formulated with varying weight ratios (95/5, 90/10, 85/15, and 80/20 wt/wt%) and PEG molecular weights (PEG-600, PEG-1500, and PEG-4000). This …
Real-Time Monitoring System For Sedentary Behavior Using Pose-Estimation Approach, Pheng Ou Chea
Real-Time Monitoring System For Sedentary Behavior Using Pose-Estimation Approach, Pheng Ou Chea
Chulalongkorn University Theses and Dissertations (Chula ETD)
Long-term sedentary behavior, defined as extended periods of sitting or inactivity, increases the risk of obesity, cardiovascular disease, and other health problems. These risks are often underestimated due to low levels of physical activity. This study proposes the use of You Only Look Once (YOLO)–based pose estimation for dwell-time analysis to monitor sedentary behavior. We examined posture over an entire day to assess prolonged inactivity and encourage individuals to balance energy expenditure with available time—such as engaging in exercise in the early morning or evening according to recommended guidelines. For employees across generations, as well as for vulnerable groups such …
A Novel Hydrothermal Synthesis Process Of Mil-53(Al) Using Bamboo Biochar As A Sustainable Precursor For Co₂ Adsorption, Pisit Phayutcharoenkun
A Novel Hydrothermal Synthesis Process Of Mil-53(Al) Using Bamboo Biochar As A Sustainable Precursor For Co₂ Adsorption, Pisit Phayutcharoenkun
Chulalongkorn University Theses and Dissertations (Chula ETD)
Among the numerous MOFs members, MIL-53 (Al) framework is one of the most interesting structures due to the breathing effect and has been widely investigated for hydrogen storage and water treatment. It is built up by the interconnection of infinite trans chains of corner-sharing AlO4(OH)2 octahedral by 1,4-benzenedicarboxylate ligands. MIL-53 crystallizes in a “wine rack” structure (Pnma, a = 17.129(2) Å, b = 6.628(1) Å, c = 12.182(1) Å, α = β = γ = 90°) with large internal pores held open by excess solvent and unreacted ligand in the as-synthesized state. Another challenge is the synthesis process and raw …
Simulation On Hydrogen Production From Mae-Moh Lignite Coal Gasification, Pitatchai Arunwong
Simulation On Hydrogen Production From Mae-Moh Lignite Coal Gasification, Pitatchai Arunwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hydrogen energy has attracted significant attention due to its cleanliness, efficiency, and sustainability. Gasification is considered one of the most promising thermochemical routes to convert coal into high-quality syngas, which can subsequently be utilized for hydrogen production. Mae-Moh lignite, a low-rank coal with low carbon content and high moisture and volatile matter, is selected as the feedstock for this study. This research aims to develop a comprehensive simulation model of a hydrogen production process, integrating gasification, water-gas shift (WGS), acid gas removal, and hydrogen purification using the software simulator. The model predicts hydrogen product gas composition from Mae-Moh lignite under …
Development Of Microfluidic Device To Monitor The Contamination In Drinking Water Using Impedance Spectroscopy, Pornpipat Oupchan
Development Of Microfluidic Device To Monitor The Contamination In Drinking Water Using Impedance Spectroscopy, Pornpipat Oupchan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Microplastic contamination is a growing concern, as microplastics have been found in brain tissue and can enter the body through consumption. The objective of this research is to develop a microfluidic device to monitor microplastic particles by using electrical impedance spectroscopy principles. The device operates based on a flow-through principle. The configuration of electrode consists of copper-based cylindrical electrode with diameter of 300 micrometer and a center-to-center spacing of 2000 micrometer. The electrodes are designed to be replaceable. The microchannel has a rectangular cross-section with a width of 2000 micrometer and a height of 1000 micrometer. The microfluidic device was …
Suppressing Bromine Volatilization In Anthraquinone–Bromine Flow Batteries Using A Low-Cost Quaternary-Ammonium Complexing Agent, Prapassorn Areebumrungsuk
Suppressing Bromine Volatilization In Anthraquinone–Bromine Flow Batteries Using A Low-Cost Quaternary-Ammonium Complexing Agent, Prapassorn Areebumrungsuk
Chulalongkorn University Theses and Dissertations (Chula ETD)
The deployment of anthraquinone-bromine redox flow batteries (AQBFBs) is hindered by the volatilization and corrosiveness of bromine (Br2), which elevates safety risks, causes active species loss, and reduces Coulombic Efficiency (CE). This study investigates the use of the low-cost additive 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHA) as a bromine-complexing agent to mitigate these issues. The CHA additive utilizes a quaternary ammonium group to electrostatically associate with bromine and polybromide species, forming stable CHA-Brn complexes. Simultaneously, its hydroxyl functionality enhances solubility in the aqueous electrolyte, which promoted the self-recovery of this oil phase to the aqueous phase and, in turn, suppresses bromine vapor pressure …
Large Language Model-Based Framework For Mental Health Support Conversation In Thai, Radchaneeporn Changpun
Large Language Model-Based Framework For Mental Health Support Conversation In Thai, Radchaneeporn Changpun
Chulalongkorn University Theses and Dissertations (Chula ETD)
As mental health support needs continue to rise in Thailand, access to professional care remains constrained. LLM-based chatbots present a scalable alternative, though most current systems are limited to single-turn, solution-focused interactions. This thesis introduces a Large Language Model-Based Framework for Mental Health Support Conversations in Thai, organizing dialogues around five fundamental mental health counseling stages: rapport building, problem identification, goal setting, working, and termination. Drawing from Person-Centered Therapy (PCT) and Acceptance and Commitment Therapy (ACT). The framework was assessed against three single-agent baseline models using LLM-simulated users, with positive user reaction rates evaluated by LLMs. Results demonstrated a 79.01% …
Development Of P-Type Cesium Iodide Thin Film For Radiation Detection By Rf-Magnetron Sputtering, Rhett Simon Tabbada
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 …