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Properties Modification Of High-Density Polyethylene Blending With Polypropylene Carbonate-Grafted-Stearic Acid, Suphiriya Khongphom
Properties Modification Of High-Density Polyethylene Blending With Polypropylene Carbonate-Grafted-Stearic Acid, Suphiriya Khongphom
Chulalongkorn University Theses and Dissertations (Chula ETD)
The purpose of this study is to improve the mechanical properties of high-density polyethylene (HDPE) by incorporating it with polypropylene carbonate-grafted-stearic acid (PPC-g-ST). PPC was modified with stearic acid to enhance interfacial adhesion and compatibility between HDPE and PPC. The blends were prepared using an internal mixer at 160°C with a rotation speed of 60 rpm for 8 minutes. PPC-g-ST was added to PPC at 3, 5, 7, and 10 wt% contents. FTIR confirmed the formation of ester linkages between the carboxylic groups of stearic acid (ST) and the hydroxyl groups of PPC through the appearance of characteristic absorption bands. …
Music Generation Using Large Language Models : A Case Study On Traditional Thai Music, Sutusta Kunasorn
Music Generation Using Large Language Models : A Case Study On Traditional Thai Music, Sutusta Kunasorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study presents a framework for music generation using Large Language Models (LLMs), focusing on the creation of symbolic compositions in the style of traditional Thai music. The framework integrates prompting techniques, retrieval-augmented generation (RAG), and multi-agent collaboration to guide the model in producing melodies that reflect Thai musical characteristics. ABC notation is used as the primary representation, allowing LLMs to process musical structure in a text-based format. The system incorporates curated Thai musical examples and theoretical knowledge to support culturally informed generation, while multiple agents work together to compose, evaluate, and refine musical ideas using rubric-based criteria adapted from …
A Hybrid Hardware Modeling, Simulation, And Generation Framework : A Case Study Of Risc-V Out-Of-Order Superscalar Cpu Design, Tanawin Devaveja
A Hybrid Hardware Modeling, Simulation, And Generation Framework : A Case Study Of Risc-V Out-Of-Order Superscalar Cpu Design, Tanawin Devaveja
Chulalongkorn University Theses and Dissertations (Chula ETD)
We present Kathryn, a novel framework that simplifies hardware design through a hybrid design flow and an integrated hybrid simulation approach. As specialized hardware demand grows, managing design complexity, precise control flow, and parallelism control remains challenging. Kathryn alleviates these issues by abstracting control logic and still maintaining designers’ cycle-accurate control ability. Moreover, Kathryn provides hardware-aggregation features, helping designers manage complex hardware component structures. As a result, in a simple RISC-V design, the model written in Kathryn shows a 2.6x reduction in lines of code compared to those of Verilog. [1] Moreover, in an Out-of-Order design, the model on Kathryn …
Endoplanar: Deformable Planar-Based Gaussian Splatting For Surgical Scene Reconstruction, Thatphum Paonim
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
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
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 …
Exploring The Lived Experience Of Moderate To Severe Premenstrual Symptoms In Women With Histories Of Emotional Maltreatment: A Thematic And Art-Based Inquiry, Hen Polat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Premenstrual Disorders (PMDs) profoundly impact women’s daily lives yet remain under-recognized and undertreated, despite evidence that most sufferers report histories of childhood trauma, particularly emotional maltreatment. This study had three objectives: to explore the lived experiences and meaning-making of women with PMDs and emotional maltreatment histories; to examine perceived connections between premenstrual distress and past trauma; and to evaluate the role of drawing as a research tool for accessing experiences difficult to verbalize. Fifteen women aged 24–43 from nine countries were recruited through online support groups and screened with the Premenstrual Symptoms Screening Tool (PSST), the Childhood Trauma Questionnaire (CTQ-SF), …
Comparative Analysis Of Gut Microbiota In Post-Mortem Chronic Alcoholics Versus Minimal To No Alcohol Users In The Thai Population, Laiba Pervez
Chulalongkorn University Theses and Dissertations (Chula ETD)
Chronic alcohol consumption induces long-term disruption of the gut microbiota, contributing to inflammation, metabolic imbalance, and impaired intestinal integrity. This study investigated 24 postmortem gut microbiota samples from the Thai population, including 12 chronic alcoholic and 12 non-alcoholic cadavers, focusing on cecal and fecal samples to identify site-specific microbial signatures of alcohol-associated dysbiosis. Following DNA extraction, the V3–V4 regions of the 16S rRNA gene were sequenced on the Illumina MiSeq platform. Data were processed in QIIME for OTU clustering and taxonomic profiling. Alpha (Shannon, Chao1, ACE) and beta (Bray–Curtis) diversity were analyzed with PERMANOVA (p< 0.05) while LEfSe, cladogram, and STAMP analyses identified differentially abundant taxa.. At the phylum level, alcoholic cecal samples (AC) showed a decrease in Firmicutes (59.07%) and increases in Proteobacteria (5.54%), Fusobacteria (8.48%), and Actinobacteria (2.78%) compared with controls (NAC). The rise in Actinobacteria was statistically significant. The class Bacilli was also elevated, reflecting a more oxygenated and inflammatory intestinal environment. At the genus level, Paeniclostridium was enriched in alcoholics, while the butyrate-producing Coprococcus was reduced, suggesting impaired SCFA metabolism and gut barrier function. In fecal samples (AF vs NAF), phylum-level differences were minimal, although Clostridium sensu stricto 1 was notably higher in alcoholics, consistent with inflammation-associated dysbiosis. When comparing gut regions, distinct spatial heterogeneity was observed. Within the alcoholic group, Firmicutes were more abundant in cecum, while Actinobacteria were lower compared to feces. Among controls, Actinobacteria and Bacteroidetes were enriched in feces, whereas Firmicutes predominated in the cecum. Alpha diversity analysis using ACE and Chao1 indices showed significant differences between cecal and fecal samples of the control group. Overall, postmortem gut microbiota retained distinct alcoholassociated signatures, with the cecum preserving clearer microbial patterns than feces. These findings highlight the cecum’s potential as a reliable site for detecting alcohol-related dysbiosis in forensics.
Recommendations For The Novel Assessment System In The Doctor Of Medicine Program From The Medical Students’ And The Educators’ Perspectives, Tanat Tabtieang
Recommendations For The Novel Assessment System In The Doctor Of Medicine Program From The Medical Students’ And The Educators’ Perspectives, Tanat Tabtieang
Chulalongkorn University Theses and Dissertations (Chula ETD)
The 2024 Doctor of Medicine curriculum at Chulalongkorn University introduced a new assessment system comprising outcome-based assessment system with milestones, a non-tiered grading model with recognition of excellence, a professional development dashboard (PDD), remediation with re-examination, and a faculty-level student profile (FLSP). This study employed a quantitative cross-sectional survey design, complemented by a sequential exploratory element, to compare student and faculty perspectives using a questionnaire across five themes, analyzed with descriptive statistics, Mann-Whitney U tests, and effect sizes (ES). A total of 490 students and 285 faculty responded. When analyzed by theme, students showed greater confidence than faculty in the …
Molecular Investigation Of Clade Classification, Knockdown Resistance And Pathogen Detection Of The Head Louse (Pediculus Humanus Capitis) Collected From Children In Ang Thong, Thailand, Urooj Gul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Human head lice (Pediculus humanus capitis) are medically significant ectoparasites due to their capacity to harbor pathogenic bacteria and the increasing prevalence of insecticide resistance. A total of 112 head lice specimens were collected from children in Ang Thong, central Thailand. Phylogenetic analysis of the mitochondrial cytb gene identified two well-supported clades, with clade A (69.2%) predominating over clade C (30.8%) in the studied population. Molecular screening revealed a high incidence of bacterial associations, with Staphylococcus aureus detected in 96.4% of specimens and Acinetobacter spp. in 2.7%. Furthermore, genotypic analysis of the voltage-sensitive sodium channel (VSSC) gene demonstrated a strikingly …
The Effects Of An Integrated Application Supported Mindfulness-Based Cognitive Therapy Program On Depression Among Adolescents With Non Suicidal Self-Injury, Russunan Jantarapakdee
The Effects Of An Integrated Application Supported Mindfulness-Based Cognitive Therapy Program On Depression Among Adolescents With Non Suicidal Self-Injury, Russunan Jantarapakdee
Chulalongkorn University Theses and Dissertations (Chula ETD)
This randomized controlled trial with repeated measures aimed to evaluate the effectiveness of an integrated application supported MBCT program in reducing depression among adolescents with NSSI. The sample consisted of 96 participants who met the inclusion criteria and were randomly assigned to either the experimental group or control group, with 48 participants in each group. The experimental group received the program, was developed based on the MBCT framework proposed by Segal et al. (2013) once a week for 60 minutes over eight weeks. Sessions were delivered through both on-site activities at schools and online meetings via the LINE application, supplemented …
Antimicrobial Activity Of Silver Nanoparticles Synthesized Using Thai Herbal Extracts, Charuwan Pradabsang
Antimicrobial Activity Of Silver Nanoparticles Synthesized Using Thai Herbal Extracts, Charuwan Pradabsang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Synthesis of silver nanoparticles (SNP) using Thai herbal plants, namely Garcinia cowa Roxb. ex Choisy (S1), Boesenbergia rotunda (L.) Mansf. (S2), Curcuma mangga Valeton & Zijp (S3), Momordica charantia L. forma abbreviata (Ser.) W. J. de Wilde & Duyfjes (S4), Persicaria odorata (Lour.) Soják (S5), Litsea elliptica Blume (S6), Gnetum gnemon Linn. var. tenerum Markgr (S7), Phaleria macrocarpa (Scheff.) Boerl. (S8), Salacia chinensis Linn. (S9) and Brachypterum scandens (Roxb.) Miq. (S10), is considerably economical and safe. Plants and preparation methods can affect properties and bioactivity such as controlled temperature of SNP. This study aimed to assess the ability of aqueous …
The Development Of Surveillance And Monitoring Tools For Pharmaceutical Supply Chain Management System For Public Health Emergencies, Kakanang Tosanguan
The Development Of Surveillance And Monitoring Tools For Pharmaceutical Supply Chain Management System For Public Health Emergencies, Kakanang Tosanguan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background: Thailand frequently experiences public health emergencies (PHEs) that severely disrupt pharmaceutical supply chain (PSC) management. This study addresses the urgent need for a specialized assessment tool to identify system weaknesses, support timely risk management, and enhance national preparedness planning.Methods: Utilizing a sequential exploratory mixed-methods design (July 2022–July 2024), the study began with a scoping review to identify existing frameworks. Following this, in-depth interviews with 36 key stakeholders synthesized conceptual domains. The draft tool underwent rigorous content validity assessment by 63 experts and was then pilot tested with 62 participants to confirm reliability (Cronbach’s alpha).Results: The evidence synthesis resulted in …
Chinese Students’ Mothers In Thailand: Transnational Education And Migration, Shan Li
Chinese Students’ Mothers In Thailand: Transnational Education And Migration, Shan Li
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focuses on Chinese mothers accompanying their children to study in Thailand, exploring their life experiences, identity transformation, and social adaptation within this transnational educational migration phenomenon. A mixed research method (questionnaire survey and interviews) was employed, systematically analyzing data from 151 questionnaires and 13 interviewed mothers. Results show that these accompanying mothers generally possess high levels of education and economic capability, with most abandoning their original professions for their children's education, forming a transnational family structure of husband remaining in China, wife accompanying her child in Thailand. While this model reinforces traditional gender roles, it also encourages women …
Evaluation Of User Experience And Usability Of Organization Super App, Ananya Kumhan
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
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 …
Development Of Potentiometric Aptasensor For The Detection Of Escherichia Coli, Chalinee Auanphui
Development Of Potentiometric Aptasensor For The Detection Of Escherichia Coli, Chalinee Auanphui
Chulalongkorn University Theses and Dissertations (Chula ETD)
A potentiometric aptasensor was developed for the rapid and label-free detection of Escherichia coli (E. coli), a major food- and water-borne pathogen of public health concern. The sensor utilized a laser-induced graphene (LIG) electrode fabricated by laser engraving on a polyimide substrate, followed by modification with an ion marker, coating with a carboxylated poly(vinyl chloride) (PVC–COOH) membrane, and immobilization of an E. coli-specific aptamer. The remaining surface was blocked with bovine serum albumin (BSA) to minimize nonspecific adsorption. Detection was based on changes in ion exchange between the ion marker and membrane upon the specific binding of E. coli to …
Evaluation Of Heavy Metal Bioaccumulation And Growth In Hemp From Chicken Manure, Vermicompost, And Wastewater Sludge With Biochar And Health Risk Assessment, Chutiphan Sangsoda
Evaluation Of Heavy Metal Bioaccumulation And Growth In Hemp From Chicken Manure, Vermicompost, And Wastewater Sludge With Biochar And Health Risk Assessment, Chutiphan Sangsoda
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hemp (Cannabis sativa L.) has become an economically valuable crop with a wide range of benefits. To promote more sustainable agricultural systems, the use of recycled substrates has increasingly replaced traditional fertilizers. However, substrates such as dry chicken manure, vermicompost, and wastewater sludge (WWS) combined with biochar often contain heavy metal contaminants, which may pose health risks through exposure to hemp. This study investigated three cultivars Rosella, Superwoman S1, and Red Robin over a 120-day period. The objectives were: (1) to compare the effects of dry chicken manure, vermicompost, and wastewater sludge (with and without biochar) on soil nutrient quality …
Removal Of Antibiotics Under Visible Light By Using C,N-Tio2 Incorporated Into Magnetite Mesoporous Silica Composites, Dwita Widyawati
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
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 …
Effect Of Single Screw Extrusion Process Parameters On Gel Formation And Properties In Polycaprolactone Films, Kitthanya Ritthichai
Effect Of Single Screw Extrusion Process Parameters On Gel Formation And Properties In Polycaprolactone Films, Kitthanya Ritthichai
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focuses on the production of polycaprolactone (PCL) films using the commercial grade CAPA 6800 through a continuous single-screw extrusion process. This method serves as an alternative to conventional solution-based film fabrication that requires solvents and chemical reagents. The effects of processing temperature (80–120 °C), screw design (mixing screw and plain screw), and extruder-barrel cooling system (water-cooled and air-cooled) on film quality, gel formation, thermal properties, and mechanical properties of PCL films were investigated. Based on the processing of high-purity PCL pellets, the results indicate that the processing temperature, screw design, and barrel-cooling system did not affect the chemical …
Blocfog : Enhanced Transactional Data Encryption Via Fog Computing And Blockchain, Leon Wirz
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
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. …
Evaluation Of Soil Erosion In The Middle Yom River Basin, Passapong Paentong
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 …
Gel Based Sensing Platforms For Ammonia Detection, Patita Salee
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 …
การศึกษาแบบแผนการเต้นของหัวใจระหว่างการวิ่ง โดยใช้การเรียนรู้ของเครื่องแบบไม่มีผู้สอนเพื่อการตรวจจับความผิดปกติ, ชวิน หังสสูต
การศึกษาแบบแผนการเต้นของหัวใจระหว่างการวิ่ง โดยใช้การเรียนรู้ของเครื่องแบบไม่มีผู้สอนเพื่อการตรวจจับความผิดปกติ, ชวิน หังสสูต
Chulalongkorn University Theses and Dissertations (Chula ETD)
การศึกษานี้มีวัตถุประสงค์เพื่อวิเคราะห์รูปแบบการเต้นของหัวใจระหว่างการวิ่ง โดยใช้เทคนิคการตรวจจับความผิดปกติแบบไม่มีผู้สอน (Unsupervised Anomaly Detection - UAD) เพื่อการตรวจจับความผิดปกติ ปัญหาหลักในงานวิจัยนี้คือข้อจำกัดทางจริยธรรมในการรวบรวมข้อมูลภาวะวิกฤตเพื่อใช้สอนแบบจำลอง และความแปรปรวนของข้อมูลสรีรวิทยาที่สูงมากระหว่างบุคคลเพื่อแก้ไขปัญหานี้ งานวิจัยนี้ได้พัฒนาระบบเว็บแอปพลิเคชันสำหรับการรวบรวมและกำกับข้อมูล โดยผู้เชี่ยวชาญ และได้สร้างชุดข้อมูลอ้างอิงจากกลุ่มตัวอย่างนักวิ่ง 5 ท่าน จากนั้น ได้ดำเนินการศึกษาเชิงเปรียบเทียบแบบจำลอง UAD จำนวน 7 แบบจำลอง โดยใช้กลยุทธ์การเรียนรู้แบบจำเพาะบุคคล ภายใต้เงื่อนไข การกำหนดค่าไฮเปอร์พารามิเตอร์แบบคงที่ เพื่อจำลองสถานการณ์การใช้งานจริงแบบเริ่มต้น โดยปราศจากการปรับแต่งค่าล่วงหน้า และประเมินผลด้วยค่า F0.5-Score เพื่อเน้นความแม่นยำและลดการแจ้งเตือนที่ผิดพลาดผลการทดลองพบว่า เมื่อไม่มีการปรับจูนพารามิเตอร์ ประสิทธิภาพโดยรวมของทุกแบบจำลองลดลงอย่างมีนัยสำคัญ ซึ่งสะท้อนถึงความท้าทายในการสร้างแบบจำลองสากล อย่างไรก็ตาม แบบจำลอง Matrix Profile (MP) ในกลุ่มคลาสสิก พิสูจน์ให้เห็นถึงความทนทานสูงที่สุด โดยมีประสิทธิภาพเฉลี่ยสูงสุด (F0.5-Score 2.71%) และสามารถตรวจจับความผิดปกติได้ดีในรายบุคคล ในขณะที่แบบจำลองพื้นฐานล้มเหลวโดยสิ้นเชิง (0.00%) สำหรับกลุ่มการเรียนรู้เชิงลึก (USAD, LSTM-AE) พบว่ามีข้อจำกัดในการใช้งานแบบเริ่มต้น (Cold-start) โดยไม่สามารถตรวจจับความผิดปกติได้แม้จะมีปริมาณข้อมูลมาก หากปราศจากการปรับแต่งค่าพารามิเตอร์ ผลลัพธ์นี้ยืนยันว่าระบบเฝ้าระวังสุขภาพในอนาคตจำเป็นต้องมีกลไกการเรียนรู้แบบปรับตัว ร่วมด้วยเพื่อให้สามารถนำไปใช้งานจริงได้อย่างมีประสิทธิภาพ
การคาดการณ์ค่าดัชนีความแตกต่างของพืชและความชื้น โดยใช้เทคนิคการเรียนรู้ของเครื่องอย่างชาญฉลาด เพื่อการติดตามด้านการเกษตรและสิ่งแวดล้อม, ณุทยา เข็มเจริญ
การคาดการณ์ค่าดัชนีความแตกต่างของพืชและความชื้น โดยใช้เทคนิคการเรียนรู้ของเครื่องอย่างชาญฉลาด เพื่อการติดตามด้านการเกษตรและสิ่งแวดล้อม, ณุทยา เข็มเจริญ
Chulalongkorn University Theses and Dissertations (Chula ETD)
ปัจจุบัน ภัยแล้งและการเปลี่ยนแปลงสภาพภูมิอากาศส่งผลกระทบต่อผลผลิตทางการเกษตร โดยเฉพาะพืชเศรษฐกิจของไทยอย่างทุเรียน ซึ่งต้องอาศัยการติดตามสุขภาพพืชและการจัดการน้ำอย่างใกล้ชิด ข้อมูลจากภาพถ่ายดาวเทียม ดัชนีความแตกต่างของพืชและความชื้น จึงเป็นเครื่องมือสำคัญในการวิเคราะห์สภาพพื้นที่เพาะปลูก โครงงานนี้พัฒนาแบบจำลองการเรียนรู้ของเครื่องเพื่อพยากรณ์ทั้งสองดัชนีรายสัปดาห์ โดยใช้การเฉลี่ยและเติมค่าข้อมูลที่ขาดหายด้วยการถดถอยเชิงเส้น ก่อนนำไปฝึกแบบจำลองผสมระหว่างโครงข่ายคอนโวลูชัน และหน่วยความจำระยะสั้นแบบยาว ระบบถูกออกแบบให้ทำงานอัตโนมัติภายใต้แนวคิดการปฏิบัติการด้านการเรียนรู้ของเครื่อง แสดงผลผ่านเว็บแอปพลิเคชัน ติดตั้งและทดสอบบนเครื่องเซิร์ฟเวอร์
Evaluation Of Blending Ability Of Single-Shade Composite Relating To Different Cavity Depths And Abrasive Wear From Toothbrushing, Nattaporn Verayangkura
Evaluation Of Blending Ability Of Single-Shade Composite Relating To Different Cavity Depths And Abrasive Wear From Toothbrushing, Nattaporn Verayangkura
Chulalongkorn University Theses and Dissertations (Chula ETD)
Materials and Method: Eighty extracted human premolars were used for the shade‑matching evaluation. The materials tested in this study were Omnichroma (OC), Vittra APS Unique (VU), Charisma Diamond One (CD), and Filtek Z350 XT (FZ, control). The initial tooth shade was determined using a dental spectrophotometer and the reference color parameters (L, C, and H) were recorded with a laboratory spectrophotometer. A 4‑mm‑diameter cylindrical cavity was prepared in each tooth at restoration depths of either 1 mm or 2 mm. The prepared teeth in each restoration depth group were further divided into four subgroups based on the resin composite material …
Cytotoxic Constituents From Cylindrolobus Mucronatus Against Glioblastoma Cells, Shune Lae Yee Soe
Cytotoxic Constituents From Cylindrolobus Mucronatus Against Glioblastoma Cells, Shune Lae Yee Soe
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study reported the phytochemical investigation of Cylindrolobus mucronatus Lindl., a member of the Orchidaceae family, focusing on its chemical constituents and cytotoxic potential against glioblastoma cells. Eleven compounds were successfully isolated and structurally characterized, including new phenanthrene derivatives, cymucronins A-D, along with seven known compounds comprising confusarin , nudol, erianthridin, coelonin, bleformin I, (2,3-trans)-2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-10-methoxy-2,3,4,5-tetrahydrophenanthro [2,1-b] furan-7-ol, and blestriarene C. Structural elucidation was accomplished using NMR, MS, IR and UV-Vis spectroscopic techniques, supported by comparison with literature data. Eight compounds were evaluated for their cytotoxic activity against U-87 human glioblastoma cells and three non-cancerous human cell lines: HEK293 (embryonic kidney), …