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Full-Text Articles in Engineering
การประเมินประสิทธิภาพของเครื่องรับสัญญาณดาวเทียมราคาประหยัดแบบหลายความถี่ด้วยเทคนิคการประมวลผลแบบจุดเดี่ยวความละเอียดสูงสำหรับการประยุกต์ใช้ในงานสำรวจด้วยอากาศยานไร้คนขับขนาดเล็ก, เจตนิพัทธ์ กิตติบุญเกศ
การประเมินประสิทธิภาพของเครื่องรับสัญญาณดาวเทียมราคาประหยัดแบบหลายความถี่ด้วยเทคนิคการประมวลผลแบบจุดเดี่ยวความละเอียดสูงสำหรับการประยุกต์ใช้ในงานสำรวจด้วยอากาศยานไร้คนขับขนาดเล็ก, เจตนิพัทธ์ กิตติบุญเกศ
Chulalongkorn University Theses and Dissertations (Chula ETD)
การผลิตแผนที่ภาพถ่ายทางอากาศด้วยอากาศยานไร้คนขับขนาดเล็กในปัจจุบัน ได้มีการนำเทคโนโลยีระบบนำทางด้วยดาวเทียม GNSS มาใช้ในการระบุตำแหน่งหมุดควบคุมภาคพื้นดิน รวมถึงการระบุตำแหน่งของอากาศยานฯนั้นด้วย ซึ่งความถูกต้องทางตำแหน่งของหมุดควบคุมฯ และตำแหน่งอากาศยานฯ ดังกล่าวนั้น เป็นส่วนสำคัญของความถูกต้องทางตำแหน่งของแผนที่ภาพถ่ายทางอากาศที่ได้จากงานสำรวจด้วยอากาศยานนี้ โดยปัจจัยที่จะทำให้ได้ตำแหน่งที่มีความถูกต้องสูง ได้แก่ ชนิดของเครื่องรับสัญญาณดาวเทียม GNSS ที่ใช้ในการรังวัด และเทคนิคการรังวัดดาวเทียม GNSS ที่นำมาประยุกต์ใช้ ซึ่งปัจจุบันนิยมใช้เครื่องรับสัญญาณดาวเทียม GNSS แบบรังวัด (Survey grade) ชนิดหลายความถี่ และเทคนิคการรังวัดดาวเทียมแบบจลน์ คือเทคนิค RTK (Real Time Kinematic) หรือ PPK (Post Processing Kinematic) ตามลำดับ อย่างไรก็ตามเครื่องรับสัญญาณดาวเทียม GNSS แบบรังวัดนั้น มีราคาค่อนข้างสูง รวมทั้งเทคนิคการรังวัดด้วยดาวเทียมแบบ RTK และ PPK นั้นยังคงมีข้อจำกัดในการนำมาประยุกต์ใช้ในงานการผลิตแผนที่ภาพถ่ายทางอากาศด้วยวิธีการนี้ กล่าวคือความถูกต้องทางตำแหน่งที่ได้รับขึ้นอยู่กับระยะห่างระหว่างสถานีฐานถึงตำแหน่งหมุดควบคุมฯ หรือตำแหน่งของอากาศยานนั้น แล้วแต่กรณี ซึ่งจะทำให้อากาศยานไร้คนขับถูกจำกัดระยะทางในการบิน ดังนั้นในงานวิจัยนี้จึงได้ทดสอบประสิทธิภาพของเครื่องรับและเสาอากาศรับสัญญาณดาวเทียม GNSS ราคาประหยัดแบบหลายความถี่ U-blox F9P ด้วยเทคนิคการหาตำแหน่งแบบจุดเดี่ยวความละเอียดสูง ซึ่งต้องการเครื่องรับสัญญาณดาวเทียมเพียงเครื่องเดียวและความถูกต้องทางตำแหน่งที่ได้รับไม่ขึ้นอยู่กับระยะห่างจากสถานีฐานใด ๆ โดยทดสอบทั้งในการรังวัดแบบสถิตและแบบจลน์ ผลการวิจัยพบว่าความถูกต้องทางตำแหน่งจากการรังวัดแบบสถิตของเครื่องรับและเสาอากาศราคาประหยัดดังกล่าวให้ความถูกต้องทางตำแหน่งทางราบและทางดิ่งที่ดีกว่า 0.03 เมตร (ซึ่งอยู่ในระดับเดียวกับเครื่องรับสัญญาณดาวเทียมแบบรังวัดที่รังวัดด้วยเทคนิค RTK) ในการทดสอบรังวัดแบบจลน์ที่ความเร็ว 10 และ 20 เมตรต่อวินาที สามารถให้ความถูกต้องทางตำแหน่งทางราบดีกว่า 0.6 เมตร และทางดิ่งดีกว่า 1.2 เมตร
Simulation Of Photoelectrochemical Co2 Conversion To Useful Chemicals, Aroonroj Chaosukho
Simulation Of Photoelectrochemical Co2 Conversion To Useful Chemicals, Aroonroj Chaosukho
Chulalongkorn University Theses and Dissertations (Chula ETD)
Photoelectrochemical (PEC) CO2 reduction reaction (CO2 RR) is one of the possible solutions to reduce CO2 emissions. Among a variety of products derived from CO2 RR, CO, and HCOO- are found to be interesting chemicals. The geometry and arrangement of the main components of PEC cells play important roles in the cell performance of CO2 RR. In this study, a correlation of hydrodynamics and kinetics on the TiO2-photoanode and SnO2-GDE, used as a cathode, was investigated by COMSOL Multiphysics by controlling operating conditions for 2-dimensional different PEC cell configurations. The Microfluidic flow cell (MFC) with a zero-gap anode with a …
Techno-Economic Analysis Of Succinic Acid Production From Sugarcane Molasses, Apitsada Rongsawad
Techno-Economic Analysis Of Succinic Acid Production From Sugarcane Molasses, Apitsada Rongsawad
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study proposes an alternative approach to address global warming concerns by introducing bio-based succinic acid production derived from molasses and waste CO2 in ethanol production as a substitute for conventional petroleum-based methods. The evaluation focuses on the downstream process; reactive extraction, aiming to assess its feasibility in terms of technical, economic, energy, and CO2 emission performance. The results indicate that the integrated process, Int. ETOH+SA 25:75, exhibits remarkable benefits, including a 66% reduction in CO2 emissions from ethanol production, a 77% decrease in energy consumption compared to petroleum-based methods, and NPV of 2,180 million USD with a 40.81% IRR …
Techno-Economic And Environmental Assessment For Enhancementbiodiesel Production Process Using Rotating Tube Reactor And Dry Washing, Arthit Jarungwongsathien
Techno-Economic And Environmental Assessment For Enhancementbiodiesel Production Process Using Rotating Tube Reactor And Dry Washing, Arthit Jarungwongsathien
Chulalongkorn University Theses and Dissertations (Chula ETD)
The study aims at exploring the potential use of rotating tube reactor (RTR) and performing economic analysis as wells as addressing the challenges associated with the utilization of different feedstocks including of refined palm oil (RPO) and waste cooking oil (WCO) for biodiesel production. The type of feedstock strongly influenced the optimum reaction temperature. For instance, RPO can produce biodiesel in the RTR at room temperature while WCO required the external heat source for biodiesel production at 65°C. In addition, two transesterification steps of WCO were required to achieve 95.16%. Simulation results found that the process intensification using RTR and …
Enzymatic Pretreatment Of Rice Bran Acid Oil Before Γ-Oryzanol Recovery, Asdarina Binti Yahya
Enzymatic Pretreatment Of Rice Bran Acid Oil Before Γ-Oryzanol Recovery, Asdarina Binti Yahya
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aims to apply enzymatic reactions for pretreating the major byproduct of rice bran oil (RBO) industry, rice bran acid oil (RBAO) before γ-oryzanol recovery. RBAO contains free fatty acids (FFAs), glycerides, and is rich in the super-antioxidant, γ-oryzanol. As a primary step to recover γ-oryzanol from RBAO, glycerides must be removed because of having similar polarity with γ-oryzanol. This study is conducted in two parts, hydrolysis and esterification/transesterification. In the first part, enzymatic hydrolysis. The study evaluates the performance of operating conditions using one factor at a time (OFAT) on the reaction time, temperature, lipase loading, water:RBAO ratio, …
Development Of Bioplastic Composite Films With Improved Antimicrobial Properties: A Comparative Study Between Blown Film Extrusion, Doctor Blading And Spray Coating, Atiwit Singhapan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB) is a bioplastic that has gained attention as a potential alternative to petroleum-based plastics in film packaging due to its good barrier properties and thermal stability. However, poly(3-hydroxybutyrate-co-4-hydroxybutyrate) has no outstanding properties. Therefore, the researcher added lignin powder to improve its antimicrobial properties, another essential property of the packaging film. This work successfully prepared a composite bioplastic film between poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and lignin powder by forming through a blown film extrusion, doctor blading, and spray coating. In order to give the film a high surface energy and enable it to adhere to the lignin solution on the surface, the …
Glycerol Carbonate Production From Glycerol And Diethyl Carbonate: A Comparative Study Between A Separated Reaction/Distillation (Srd) Process And A Reactive Distillation (Rd) Process, Chayanin Sriharuethai
Glycerol Carbonate Production From Glycerol And Diethyl Carbonate: A Comparative Study Between A Separated Reaction/Distillation (Srd) Process And A Reactive Distillation (Rd) Process, Chayanin Sriharuethai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Glycerol carbonate is one of the valuable products that can be converted from glycerol produced in the biodiesel industry. In this work, the continuous process of glycerol carbonate production via transesterification from crude glycerol and diethyl carbonate will be developed using Aspen Plus simulation. There are two processes to be considered. First, the separated reaction/distillation (SRD) process consists of a continuously stirred tank reactor for the reaction section and a distillation column for the purification section. Second, the reactive distillation (RD) process consists of a reactive distillation column that can accommodate both the reaction and purification in a single column, …
Parameters Optimization In Chlor-Alkali Ion-Exchange Membrane Electrolysis Process With Artificial Neural Network, Kittapas Sukantowong
Parameters Optimization In Chlor-Alkali Ion-Exchange Membrane Electrolysis Process With Artificial Neural Network, Kittapas Sukantowong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Since ion-exchange membrane electrolysis cell has developed for producing Chlor-Alkali products. New higher efficiency and lower consumption technology are released from licensors yearly, which made the process correlation deviate from the original design. The machine learning is used with “Neural Network Fitting Tool (nftool)” in MATLAB. To find a correlation between 5 inputs consisting of current density (CD, KA/m2), operation day (DOL, day), feed brine flow rate (QFB, m3/h), feed caustic flow rate (QHD, m3/h), cell temperature (T, degC) and one output which is cell voltage (CV, V). Datasets were collected from the plant information management system “exaquantum” historian database. …
Economic Evaluation Of Ethyl Lactate Production Via Reactive Distillation At Different Concentrations Of Lactic Acid, Nattapat Klin-U-Bol
Economic Evaluation Of Ethyl Lactate Production Via Reactive Distillation At Different Concentrations Of Lactic Acid, Nattapat Klin-U-Bol
Chulalongkorn University Theses and Dissertations (Chula ETD)
Ethyl lactate is a green solvent made from agricultural crops, making it more environmentally friendly than petrochemical solvents. The product is obtained via esterification of lactic acid with ethanol over Amberlyst-15 acid catalyst in a reactive distillation column. In commercial-scale production of ethyl lactate, this work designs production processes at two concentrations of lactic acid (50 and 85 wt.%) and two ethanol feed temperatures (25 and 85 °C). Highly concentrated lactic acid can result in adverse effects, such as increased oligomers and reduced desired products, making a comprehensive simulation of the production process necessary to evaluate energy consumption, economics, and …
Simultaneous Reaction And Separation Technologies For Biodiesel Production Derived From Alternative Feedstocks, Nattawat Petchsoongsakul
Simultaneous Reaction And Separation Technologies For Biodiesel Production Derived From Alternative Feedstocks, Nattawat Petchsoongsakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focused on the production of biodiesel using hybridized reactive distillation (hybridized RD) and centrifugal contractor reactor (CCR) from waste cooking oil (WCO) to reduce the operating cost. However, WCO contains some water which can cause saponification. The study showed that using two heat exchangers with hybridized RD is a simple method for water removal but it required the highest energy and cost (1.63 $/kg biodiesel). The extended spacing stage for water removal required a new hybridized RD construction with additional spacing stages. This method can handle and require less energy, resulting in lower cost (1.07 $/kg biodiesel). The …
Sulfur-Tolerant Cobalt-Doped La0.3sr0.7tio3-D-Perovskite Cathode For Intermediate-Temperature Solid Oxide Electrolysis Cell, Natthamon Nuengjumnong
Sulfur-Tolerant Cobalt-Doped La0.3sr0.7tio3-D-Perovskite Cathode For Intermediate-Temperature Solid Oxide Electrolysis Cell, Natthamon Nuengjumnong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Lanthanum doped strontium titanate (LST) is a perovskite cathode in Solid Oxide Electrolysis Cell (SOEC) which shows great performance in syngas production from CO2 and steam feed. However, the LST type cathode suffers from structural stability. Sulfur containing in industrial exhaust gas can affect its durability which inhibit the technology in real application. Therefore, to improve sulfur tolerance, La0.3Sr0.7Ti1-yCoyO3-δ (LSTC) by adding Co2+ metal ion at B-site when y is 0 to 20%mol was synthesized. Citrate acid-nitrate combustion method was used and the synthesized powder. LST and La0.3Sr0.7Ti0.9Co0.10O3-δ (LSTC0.10) exhibited single phase perovskite while La2O3 and La(OH)3 were observed in …
Ethylene Polymerization With Zirconocene Catalyston Zeolite A Support Derived From Fly Ash, Natthapat Warintha
Ethylene Polymerization With Zirconocene Catalyston Zeolite A Support Derived From Fly Ash, Natthapat Warintha
Chulalongkorn University Theses and Dissertations (Chula ETD)
Zeolite A (LTA) synthesis from fly ash has many applications, in which metallocene catalytic support is uncommon. This research study has three parts. Firstly, investigation of the effects of immobilized MAO cocatalyst and zirconocene catalyst techniques on silica support. Immobilized MAO, followed by metallocene catalyst method had the highest catalytic activity, which was used in the next parts. The second part examined the optimal temperature and [Al]MAO/[Zr]cat ratio with ethylene polymerization in a semi-batch autoclave reactor utilizing LTA-supported metallocene catalysts. The optimal conditions were found at 80°C and [Al]MAO/[Zr]cat ratios equal to 2000 that were used in the next section. …
Characteristics And Catalytic Properties Of Copper On Mcf-Si And Sba-15 For Hydrogenation Of Carbon Dioxide, Sirimas Suelueam
Characteristics And Catalytic Properties Of Copper On Mcf-Si And Sba-15 For Hydrogenation Of Carbon Dioxide, Sirimas Suelueam
Chulalongkorn University Theses and Dissertations (Chula ETD)
At present, the production of methanol from the hydrogenation of carbon dioxide is widespread. The current popular catalysts include copper oxide, zinc oxide and aluminum oxide (CZA) catalysts. As the reaction progresses, the catalyst forms coke. This causes the efficiency of the catalyst to decrease. In this study, the copper catalyst on the mesoporus silica support was investigated. This type of support has high thermal stability. Cu catalysts were synthesized on MCF-Si and SBA-15 supports with different pore morphology such as spherical and hexagonal shape, respectively, by wetness impregnation (W) method and incipient wetness impregnation (IW) with a copper loading …
Comparison Of Techno-Economic Analysis Of 1,3-Propanediol Production From Crude Glycerol Via Chemical And Biological Methods, Sivatchaya Boriboon
Comparison Of Techno-Economic Analysis Of 1,3-Propanediol Production From Crude Glycerol Via Chemical And Biological Methods, Sivatchaya Boriboon
Chulalongkorn University Theses and Dissertations (Chula ETD)
At present, the biodiesel industry is expanding rapidly which could lead to an oversupply of the by-product, crude glycerol. To manage this, crude glycerol should be converted into value-added chemicals such as 1,3-propanediol (1,3-PDO). In this study, the production of 1,3-PDO via catalytic reaction is simulated using a process simulator to evaluate its techno-economic performance as well as its environmental impact. The obtained results will be compared with the conventional production of 1,3-PDO to point out the advantages that the catalytic reaction can offer in terms of economic, energy utilization, raw material utilization, and environmental impacts.
Scale Up Of Benzoxazinone Derivative Synthesis In Batch Reactor, Sumate Boonkird
Scale Up Of Benzoxazinone Derivative Synthesis In Batch Reactor, Sumate Boonkird
Chulalongkorn University Theses and Dissertations (Chula ETD)
Benzoxazinone derivative is one of starting materials in the synthesis of Deferasirox (a Chelating iron for thalassemia patient). The parameters of Benzoxazinone derivative synthesis were investigated from the condensation of salicylic acid, salicylamide, cyanuric chloride, and triethylamine using toluene as solvent. The mole equivalent ratio of salicylic acid: salicylamide:cyanuric chloride:triethylamine at 1:1:0.67:1 provided the 46.77% yield of Benzoxazinone derivative in laboratory scale. Surprisingly, 4-chloro-2-(2-hydroxyphenyl)-4H-benzo[e][1,3]oxazine-4-ol was observed in the synthesis of Benzoxazinone derivative. In addition, the reaction scheme of Benzoxazinone derivative synthesis was proposed as a model for the study of the chemical kinetic constant. Furthermore, the scale up of Benzoxaxinone …
Effects Of Zinc Oxide On Thermal, Mechanical, Morphological, And Gas Barrier Properties Of Polybutylene Succinate/ Poly(3-Hydroxybutyrate-Co-4-Hydroxybutyrate) Films, Sunisa Suwatthi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Currently, conventional polymers from petrochemical processes have low biodegradability and remain in the environment for several hundred years. This has negative effects on the environment. This research aims to improve the properties of biopolymers such as poly(butylene succinate) (PBS) and poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P3HB4HB). P3HB4HB was selected to blend with PBS in with weight ratios of PBS:P3HB4HB was 90/10 and ZnO nanoparticles (0.5, 1 and 2%) was selected as a nucleating agent. The melt blending process using an internal mixer and molded into a film using a compression molding process. The chemical structures, morphological properties, thermal properties, dynamic mechanical properties, mechanical properties …
Control Of A Polybutylene Succinate (Pbs) Polymerization In A Semi-Batch Reactor By Neural Network Model Based Predictive Controller, Takorn Plengsangsri
Control Of A Polybutylene Succinate (Pbs) Polymerization In A Semi-Batch Reactor By Neural Network Model Based Predictive Controller, Takorn Plengsangsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polybutylene succinate (PBS) is a biodegradable plastic known for its strength and versatility in various applications. This research presents a data-driven approach to simulate temperature control in a semi-batch reactor during polymerization, the performance of the proposed approaches was compared against conventional controllers, including PID control and first-principles model MPC control. The study developed neural network model-based predictive control (NNMPC) and multiple neural network model-based predictive control (Multi-NNMPC), using Python and Tensorflow. Neural network models were trained by using a wide range of dynamic data with varying numbers of neurons in hidden layers to investigate the process dynamics under different …
Design Of Process For Recovery Of Gold And Nickel Ions From Wastewater Of Metal Plating Process In Electronics Industry Using Hollow Fiber Supported Liquid Membrane, Wanchalerm Srirachat
Design Of Process For Recovery Of Gold And Nickel Ions From Wastewater Of Metal Plating Process In Electronics Industry Using Hollow Fiber Supported Liquid Membrane, Wanchalerm Srirachat
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the manufacture of printed circuit boards (PCBs), electroless nickel immersion gold (ENIG) plating is widely applied. During the plating process, excess nickel and gold plating solutions, which adheres to the workpiece, is removed. As a result, economical quantities of nickel and gold ions accumulate in the rinse water baths and can then be collected. In this work, the simultaneously selective extraction and recovery of nickel and gold ions using a single-step operation of hollow fiber supported liquid membrane (HFSLM) technique was studied. Real rinse wastewater from the plating process containing trace nickel ions (Ni(II)) of 15 mg/L and gold …
The Study Of Weave-Pattern Effect On Filtration Performance Of Woven Filter Cloths By Computational Fluid Dynamic Modeling, Wisit Bandasak
The Study Of Weave-Pattern Effect On Filtration Performance Of Woven Filter Cloths By Computational Fluid Dynamic Modeling, Wisit Bandasak
Chulalongkorn University Theses and Dissertations (Chula ETD)
An important global problem that has an impact on both human health and the environment is air pollution. Exercise and outdoor activities are essential for human well-being, but they can also have a detrimental effect on health and the environment. For example, PM2.5 and PM10 particles can enter the lungs and cause respiratory and cardiovascular disorders. Moreover, masks must be worn in order to stop the COVID-19 epidemic from spreading. Nevertheless, not all masks are effective in preventing viruses and air pollution. Consequently, selecting the proper mask is essential for avoiding health risks. Using the use of computational fluid dynamics, …
An Analytical Network Process (Anp) Model For Choosing Optimal Public-Private Partnership (Ppp) Contract Types For Infrastructure Projects, Su Lae Yee Zaw
An Analytical Network Process (Anp) Model For Choosing Optimal Public-Private Partnership (Ppp) Contract Types For Infrastructure Projects, Su Lae Yee Zaw
Chulalongkorn University Theses and Dissertations (Chula ETD)
With the rapid social and economic development, a great deal of expenditure is crucial for the nation's infrastructure development. Nevertheless, the governments of many developing nations have been experienced with the limited budget and technical inability to deliver effective public infrastructures. Public-private partnership (PPP) has been adopted as an alternative collaboration arrangement between the government and the private sector in many nations to overcome these challenges. PPP can be defined as a long-term contract between a public agency and a private entity for rendering public facilities, including design, construct, finance, operate, and manage the project. The PPP contract types can …
Mediastinal Lymph Node Detection And Segmentation Using Deep Learning, Al-Akhir Nayan
Mediastinal Lymph Node Detection And Segmentation Using Deep Learning, Al-Akhir Nayan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Automatic lymph node (LN) segmentation and detection for cancer staging are critical. In clinical practice, computed tomography (CT) and positron emission tomography (PET) imaging detect abnormal LNs. Despite its low contrast and variety in nodal size and form, LN segmentation remains a challenging task. Deep convolutional neural networks frequently segment items in medical photographs. Most state-of-the-art techniques destroy image's resolution through pooling and convolution. As a result, the models provide unsatisfactory results. Keeping the issues in mind, a well-established deep learning technique UNet++ was modified using bilinear interpolation and total generalized variation (TGV) based upsampling strategy to segment and detect …
Recasnet: Reducing Mismatch Within The Two-Stage Mitosis Detection Framework, Chawan Piansaddhayanon
Recasnet: Reducing Mismatch Within The Two-Stage Mitosis Detection Framework, Chawan Piansaddhayanon
Chulalongkorn University Theses and Dissertations (Chula ETD)
Mitotic count (MC) is an important histological parameter for cancer diagnosis and grading, but the manual process to obtain this metric is tedious and not fully reproducible across different pathologists. To mitigate this problem, several deep learning models have been utilized to speed up the process. Typically, the problem is formulated as a two-stage deep learning pipeline: the detection stage for proposing the potential candidates for mitotic cells and the classification stage for refining prediction confidences from the former stage. However, this paradigm can lead to inconsistencies in the classification stage due to the poor prediction quality of the detection …
Leverage Graph Neural Network For Molecular Properties Prediction, Kamol Punnachaiya
Leverage Graph Neural Network For Molecular Properties Prediction, Kamol Punnachaiya
Chulalongkorn University Theses and Dissertations (Chula ETD)
During the age of deep learning technologies, which have exhibited significant potential in reducing costs and expediting medical development, predicting molecular properties has become a prevalent task that capitalizes on the capabilities of deep learning. This thesis proposed a multimodal Graph Neural Network (GNN) model that utilizes the topology information obtained from molecular graphs through a baseline GNN, facilitating precise property predictions. The thesis improves the baseline CMPNN model by exploring various methods to address potential missing gaps. These methods include incorporating the multimodal module, such as a Bidirectional LSTM module capable of processing text sequences in SMILES format or …
Service Placement Optimization For Location-Based Service, Karnkitti Kittikamron
Service Placement Optimization For Location-Based Service, Karnkitti Kittikamron
Chulalongkorn University Theses and Dissertations (Chula ETD)
Location-based service (LBS) is necessary and useful for several applications including navigation and games. These real-time applications require high accuracy and low delay. In general, the complexity of indoor localization algorithms used in LBS depends on the size of fingerprint data. This can lead to long delays when operating in large-scale areas. In this paper, we propose a novel optimization framework for edge service placement, aiming at minimizing the overall cost of edge computing deployment and service response time. Our placement strategy is used to solve the formulated edge node placement problems. The simulated annealing approach is then used in …
Machine Learning For Wavelet-Based Valve Stiction Detection, Kris Prasopsanti
Machine Learning For Wavelet-Based Valve Stiction Detection, Kris Prasopsanti
Chulalongkorn University Theses and Dissertations (Chula ETD)
Valve stiction presents challenges in industrial process control, leading to oscillations and hindering the regulation of fluid flow. This thesis addresses the detection of valve stiction by exploring the limitations of current methods and proposes a novel approach that combines wavelet reconstruction and convolutional neural networks (CNN) to enhance stiction detection performance. The proposed method utilizes preprocessed process variable versus controller output (PV(OP)) plots as input to the CNN model, capitalizing on the distinctive characteristics of stiction. Training and evaluation employ both simulated and real-world data from the International Stiction Data Base (ISDB), with the F1 score serving as the …
Deep Reinforcement Learning For Electricity Energy Trading, Manassakan Sanayha
Deep Reinforcement Learning For Electricity Energy Trading, Manassakan Sanayha
Chulalongkorn University Theses and Dissertations (Chula ETD)
The deregulation and liberalization of the energy market in the 1990s prompted short-term electricity trading, allowing energy markets to produce net output over a range of time periods as a result of this decentralized system, most commonly minutes to days ahead of time. The energy industry urgently requires a system that has undergone substantial modernization in place to handle a variety of issues, including the current climate, renewable resources, and the energy framework. In this dissertation, we investigate a deep reinforcement learning framework for both wholesale and local energy trading, which probes the challenge of RL to optimize the real-world …
Real-Time Image Classification For Malignant Biliary Strictures On Cholangioscopy Images Based On Deep Learning Approach, Passakron Phuangthongkham
Real-Time Image Classification For Malignant Biliary Strictures On Cholangioscopy Images Based On Deep Learning Approach, Passakron Phuangthongkham
Chulalongkorn University Theses and Dissertations (Chula ETD)
It is challenging to determine if the cause of bile duct strictures is benign or malignant. Currently, endoscopists may more precisely inspect the bile duct thanks to computerized single-operator cholangioscopy. As a result, lesions in the bile duct can be seen with the naked eye. However, endoscopists continue to diagnose patients differently. Consequently, a biopsy is typically regarded as the gold standard. The necessity to repeat operations results from a biopsy sample mistake that results in a false-negative cancer diagnosis. In this study, we suggest a convolutional neural network developed particularly for real-time malignant biliary stricture classification. Our approach, which …
Formal Models For Consent Management In Healthcare Software System Development, Neda Peyrone
Formal Models For Consent Management In Healthcare Software System Development, Neda Peyrone
Chulalongkorn University Theses and Dissertations (Chula ETD)
In the era of data-driven opportunities, many businesses are missing the data-privacy challenge, which leads to risks in safeguarding their customers’ data. To empower individuals (data subjects) to control their data, the General Data Protection Regulation (GDPR) mandated businesses or organizations (data controllers) to protect individuals’ data (personal data) within data protection law. Nevertheless, many businesses still struggle to enhance and develop their software systems to comply with the GDPR because it is difficult to interpret and apply to software development practices. Besides, the processing of personal data begins when the data subject provides explicit consent to the data controller, …
Real-Time Gastric Intestinal Metaplasia Semantic Segmentation With Multiple Abnormalities Using Deep Learning Approach, Passin Pornvoraphat
Real-Time Gastric Intestinal Metaplasia Semantic Segmentation With Multiple Abnormalities Using Deep Learning Approach, Passin Pornvoraphat
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis declares the segmentation of gastric intestinal metaplasia (GIM) in real-time. Recently, GIM segmentation of endoscopic images has been conducted to distinguish GIM from a healthy stomach. However, achieving real-time detection is difficult. Challenging conditions include multiple color modes (white light endoscopy and narrow-band imaging), other abnormal lesions (erosion and ulcer), noisy labels, etc. Herein, our model is based on BiSeNet and can overcome the many issues regarding GIM. Applying auxiliary head and loss boosts the performance on multiple color modes. In addition, pre-processing techniques, including location-wise negative sampling, jigsaw augmentation, and label smoothing, are utilized to improve detection …
แบบจำลองคุณภาพซอฟต์แวร์โอเพนซอร์ซเพื่อการวัดคุณภาพอย่างอัตโนมัติ, อัรกอม มะแดเฮาะ
แบบจำลองคุณภาพซอฟต์แวร์โอเพนซอร์ซเพื่อการวัดคุณภาพอย่างอัตโนมัติ, อัรกอม มะแดเฮาะ
Chulalongkorn University Theses and Dissertations (Chula ETD)
ปัจจุบันได้มีการนำเสนอแบบจำลองคุณภาพซอฟต์แวร์โอเพนซอร์ซหลายแบบจำลองเพื่อใช้ในการประเมินคุณภาพของซอฟต์แวร์โอเพนซอร์ซ แต่แบบจำลองเหล่านั้นมีข้อจำกัดเนื่องจากเป็นการประเมินตามความคิดส่วนตัวซึ่งต้องอาศัยผู้ใช้ในการประเมิน และแบบจำลองดังกล่าวต้องการข้อมูลจากหลากหลายแหล่ง เพื่อเสริมการประเมินคุณภาพซอฟต์แวร์โอเพนซอร์ซที่เป็นอยู่ให้ทำได้สมบูรณ์มากยิ่งขึ้น วิทยานิพนธ์นี้จึงได้นำเสนอแบบจำลองคุณภาพซอฟต์แวร์โอเพนซอร์ซใหม่ที่ชื่อว่าโอเอสเอส-เอคิวเอ็ม โดยมีเป้าหมายเพื่อการวัดคุณภาพซอฟต์แวร์โอเพนซอร์ซอย่างอัตโนมัติ แบบจำลองโอเอสเอส-เอคิวเอ็มได้นำเสนอตัววัดคุณภาพและเครื่องมืออัตโนมัติที่สามารถดึงข้อมูลเกี่ยวกับซอฟต์แวร์โอเพนซอร์ซจากกิตฮับ ซอร์ซโค้ด โซนาร์คิวบ์ และสแต็กเอกซ์เชนจ์ ทำให้สามารถกำหนดคะแนนคุณภาพของซอฟต์แวร์โอเพนซอร์ซได้ โอเอสเอส-เอคิวเอ็มได้รับการตรวจสอบจากวิศวกรซอฟต์แวร์ที่มีประสบการณ์ในการเลือกใช้ซอฟต์แวร์โอเพนซอร์ซ นอกจากนี้การจัดลำดับซอฟต์แวร์โอเพนซอร์ซโดยเครื่องมือโอเอสเอส-เอคิวเอ็มยังถูกนำไปเปรียบเทียบกับการจัดลำดับด้วยวิธีอื่น และพบว่าการจัดลำดับของโอเอสเอส-เอคิวเอ็มมีสหสัมพันธ์ระดับต่ำมากถึงปานกลางในทิศทางตรงกันข้ามกับวิธีจัดลำดับอื่น ๆ ตามความคิดเห็นและความนิยมของผู้ใช้ และมีสหสัมพันธ์ระดับปานกลางในทิศทางเดียวกันกับวิธีการจัดลำดับอื่นที่เน้นการตรวจสอบความมั่นคงที่ซอฟต์แวร์โดยตรง ทั้งนี้เนื่องจากโอเอสเอส-เอคิวเอ็มครอบคลุมปัจจัยคุณภาพหลายอย่างที่ไม่ได้ถูกพิจารณาโดยวิธีการจัดลำดับอื่น ๆ ดังกล่าว โอเอสเอส-เอคิวเอ็มจึงให้ข้อมูลด้านคุณภาพของซอฟต์แวร์โอเพนซอร์ซในเชิงลึกที่ดีกว่า