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Full-Text Articles in Engineering
การปรับปรุงกำลังการผลิตของกระบวนการเตรียมยาง: กรณีศึกษาโรงงานผลิตยางรถยนต์, ชุติภา ลิ้มศรีวาณิชยกร
การปรับปรุงกำลังการผลิตของกระบวนการเตรียมยาง: กรณีศึกษาโรงงานผลิตยางรถยนต์, ชุติภา ลิ้มศรีวาณิชยกร
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยฉบับนี้มีวัตถุประสงค์ในการเพิ่มกำลังการผลิตสำหรับกระบวนการตัดเตรียมยาง เนื่องจากความต้องการของลูกค้ามีเพิ่มมากขึ้น และไม่ให้เกิดคอขวดในสายการผลิต จึงทำการปรับปรุงโดยใช้เทคนิคลีน เพื่อลดความสูญเปล่าที่เกิดขึ้นในกระบวนการผลิต ในสภาพปัจจุบันกระบวนการเตรียมยางมีกิจกรรมที่ไม่สร้างคุณค่าอยู่มาก โดยขั้นตอนงานวิจัยเริ่มจากการเก็บข้อมูลกิจกรรม เวลา และการไหลตามสภาพปัจจุบันของกระบวนการเพื่อศึกษาของกระบวนการตัดเตรียมยางที่เป็นคอขวดในการผลิตยาง จากนั้นวิเคราะห์ความสูญเสียของกระบวนการโดยการระดมสมองจากทีมงานและใช้แผนผังสายธารแห่งคุณค่า (Value Stream Mapping) ในการระบุถึงกิจกรรม NA NVA และ NNVA เมื่อทราบสาเหตุแล้วจึงนำหลักการ ECRS (Eliminate, Combine, Rearrange, Simplify) มาประยุกต์ใช้ในการลดกิจกรรมและการเคลื่อนไหวที่ไม่จำเป็น รวมไปถึงการใช้ระบบคัมบัง การกำหนดเวลามาตรฐานในการทำงาน และจัดแผนผังการไหลของกระบวนการ จึงส่งผลให้เวลาและความถี่ของกิจกรรมที่ไม่เกิดคุณค่าลดลง จากผลงานวิจัยเมื่อเปรียบกระบวนการก่อนและหลังการปรับปรุงพบว่าสามารถลดเวลาของกิจกรรมได้ 7146.6 เซ็นตินาที (71.5 นาที) ต่อกะ โดย 1 นาทีมีค่าเท่ากับ 100 เซ็นตินาที หรือคิดเป็นร้อยละ 16.4 และสามารถลดระยะทางของการขนส่งจากเดิม 151.3 เมตร ลดเหลือ 59.9 เมตรต่อกะ กำลังการผลิตการเตรียมยางเพิ่มขึ้นโดยเฉลี่ยจาก 199 ก้อนต่อกะเวลา เป็น 255 ก้อนต่อกะเวลา
การเพิ่มอัตราผลผลิตของการตรวจสอบยางรถยนต์, ธนกร สงวนวงศ์วาน
การเพิ่มอัตราผลผลิตของการตรวจสอบยางรถยนต์, ธนกร สงวนวงศ์วาน
Chulalongkorn University Theses and Dissertations (Chula ETD)
ในการศึกษากระบวนการตรวจสอบยางรถยนต์พบว่าผลผลิตไม่ได้ตามเป้าหมายที่กำหนด ดังนั้นงานวิจัยฉบับนี้จึงมีวัตถุประสงค์เพื่อเพิ่มอัตราผลผลิตของการตรวจสอบยางรถยนต์ โดยมุ่งเน้นในการปรับปรุงรอบเวลา (Cycle time) การตรวจสอบยางรถยนต์ ให้ลดลง ซึ่งใช้หลักการการศึกษางานและเวลา วิเคราะห์กระบวนการทำงานจากแผนผังสายธารแห่งคุณค่า (Value Stream Mapping) และบ่งชี้กิจกรรมที่ไม่ก่อเกิดมูลค่าเพิ่ม (Non-value-added) ที่ส่งผลต่อกระบวนการทำงาน จากนั้นจึงนำหลักการ ECRS เป็นเครื่องมือในการวิเคราะห์และลดกิจกรรมที่สูญเปล่าจากกระบวนการทำงาน จากการวิเคราะห์ข้อมูลพบว่าในกระบวนการทำงานมีการทำงานที่ซ้ำซ้อน การขนส่งที่ไม่จำเป็น และท่าทางการเคลื่อนไหวในกระบวนการผลิตที่เป็นกิจกรรมที่ไม่ก่อเกิดมูลค่าเพิ่ม ซึ่งทำให้อัตราผลผลิตลดลง ส่งผลให้รอบเวลาสำหรับการตรวจสอบยางรถยนต์มากขึ้นเมื่อเทียบกับเป้าหมาย หลังจากได้ทำการปรับปรุงการทำงานจากการลดกิจกรรมที่ไม่ก่อเกิดมูลค่าเพิ่ม สามารถลดขั้นตอนของกระบวนการตรวจสอบยางรถยนต์เกรด A จากเดิม 17 ขั้นตอน เป็น 14 ขั้นตอน กระบวนการตรวจสอบยางรถยนต์เกรด B จากเดิม 18 ขั้นตอน เป็น 15 ขั้นตอน กระบวนการตรวจสอบยางรถยนต์เกรด C จากเดิม 26 ขั้นตอน เป็น 23 ขั้นตอนและกระบวนการตรวจสอบยางรถยนต์เกรด D จากเดิม 27 ขั้นตอน เป็น 26 ขั้นตอน โดยจากการลดขั้นตอนการทำงานทำให้รอบเวลาการตรวจสอบยางรถยนต์จากเดิมเฉลี่ย 77 เซ็นตินาที (47.40 วินาที) ต่อเส้น เป็น 69 เซ็นตินาที (39.60 วินาที)ต่อเส้น หรือคิดเป็น 16.46 เปอร์เซ็นต์ โดย 1 วินาที จะเท่ากับ 0.6 เซ็นตินาที ส่งผลให้พนักงานตรวจสอบยางรถยนต์ได้มากขึ้นจากเดิม 288 เส้นต่อคนต่อวัน เป็น 316 เส้นต่อคนต่อวัน
Power Loss Minimization With Second Order Cone Programming Relaxation, Akira Chuppawa
Power Loss Minimization With Second Order Cone Programming Relaxation, Akira Chuppawa
Chulalongkorn University Theses and Dissertations (Chula ETD)
The minimization of power loss in distribution systems is very important to increase the reliability and performance of the system. Therefore, this thesis determines power loss minimization in a power system. The active power loss can be minimized by the alternating current optimal power flow (ACOPF) under the limits of power generations, bus voltages, and distribution lines. The general ACOPF problem is computationally intractable in practice owing to the nonlinear objective function and nonlinear constraints. Accordingly, the conventional ACOPF is a nonconvex and NP-hard optimization problem. To address this difficulty, this work develops the computation of the ACOPF by applying …
Electrode Improvement And Neural Network-Based Dynamic Optimization Of Vanadium Redox Flow Battery, Apisada Chutimasakul
Electrode Improvement And Neural Network-Based Dynamic Optimization Of Vanadium Redox Flow Battery, Apisada Chutimasakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
The performance improvement of a vanadium redox flow battery (VRFB) was focused on this study. The two objectives of this study were (1) to investigate the effect of the operating temperatures of the Atmospheric Pressure Plasma jets (APPJs) process on the energy efficiency of the VRFB and (2) to determine the optimal electrolyte flow rate of the VRFB by solving a dynamic optimization based on a neural network model of the VRFB. The APPJs graphite felt electrode treatment temperature providing the highest energy efficiency of the VRFB was 550°C, explained by the Energy Dispersive X-ray Spectrometry (EDX) and X-ray photoelectron …
Optimization Model For Chemical Tank Container Management, Atiwich Anantkijthamrong
Optimization Model For Chemical Tank Container Management, Atiwich Anantkijthamrong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Owing to lack of appropriate tool for operational decision, this study aims to develop an optimization model for chemical tank container management using linear programming methodology. The objective function is to maximize net profit while taking container routing, empty container repositioning, and container spot leasing into account as decision variables. The basic constraints used in the model are related to spot demand accommodation and conservation of tank container flows. On top of that, additional repositioning constraints and financial incentives may be utilized to promote empty container repositioning, hence, allow the model to behave alike actual operation. The model results show …
Techno-Economic Analysis Of Diethyl Ether Production Via Catalytic Dehydration Of Ethanol, Boonraksa Chaiapha
Techno-Economic Analysis Of Diethyl Ether Production Via Catalytic Dehydration Of Ethanol, Boonraksa Chaiapha
Chulalongkorn University Theses and Dissertations (Chula ETD)
The major source of energy comes from non-renewable fuels, which have a non-sustainability and negative impact on the environment. Thus, there is change to renewable fuels as bioethanol. Diethyl ether (DEE) is a part of bioethanol. However, the increase of electric vehicles (EV) may decrease ethanol demand for biofuel in the future. Thus, it will be interesting in adding value to ethanol via the catalytic dehydration to produce DEE by conduct techno-economic analysis. Further, there is comparison on different concentrations of ethanol (93% and 95% ethanol) that affect DEE production. For simulation part, the DEE capacity of 3,600 tons/year is …
A Hybrid Electronic Nose System Based On Metal Oxide Semiconductor Gas Sensors And Compact Paper-Pased Colorimteric Sensors For Volatile Organic Compounds Classification, Aung Khant Maw
Chulalongkorn University Theses and Dissertations (Chula ETD)
Commercial metal oxide semiconductor (MOS) sensors usually employed in electronic noses (e-noses) are well known for being low-cost, portability, and ease of use. However, these sensors can only identify a limited number of odors due to insufficient selectivity. Recent studies improved the selectivity by jointly integrating the MOS sensors with additional sensor sources. However, the published hybrid systems involved complex fabrication and measurement procedures. On the contrary, this work utilizes paper-based colorimetric sensors which are simpler and easier to use. This proposed hybrid system consists of 8 commercial metal oxide sensors and a paper-based colorimetric sensor coated with phenol red, …
Characteristics Improvement Of Quantum Dot Semiconductor Optical Amplifier For Access Network, Budsara Boriboon
Characteristics Improvement Of Quantum Dot Semiconductor Optical Amplifier For Access Network, Budsara Boriboon
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis presents the characteristics improvement and performance evaluation of Quantum Dot Semiconductor Optical Amplifier (QD SOA) in an access network. There are 3 parts: 1) improvement of internal quantum efficiency, 2) increase of chip gain and 3) implementation of QD SOA in 40 Gb/s access network. The first part, Rapid Thermal Annealing (RTA) is applied to improve internal quantum efficiency to be 1.4 times higher than without RTA and low optical loss. The second part, strain compensation technique is applied to increase the chip gain of QD SOA. Considering the design of Quantum Dot Laser Diode with optimized stacked …
A Robust System For Core Thai Natural Language Processing Technologies, Can Udomcharoenchaikit
A Robust System For Core Thai Natural Language Processing Technologies, Can Udomcharoenchaikit
Chulalongkorn University Theses and Dissertations (Chula ETD)
As the amount of unstructured textual data grows, it becomes increasingly important to build an intelligent system that can process it. Natural Language Processing (NLP) is a technology that allows a computer to exploit human languages to perform tasks. Deep learning models have shown excellent results across fundamental tasks in NLP, such as word segmentation, part-of-speech tagging, and named-entity recognition. However, in many situations, these proposed methods fail to perform well. For an NLP system to be robust, it must address issues such as out-of-vocabulary and spelling-mistakes. This thesis's research goal is to develop NLP models that can handle malformed …
Semi-Supervised Thai Sentence Segmentation Using Local And Distant Word Representations, Chanatip Saetia
Semi-Supervised Thai Sentence Segmentation Using Local And Distant Word Representations, Chanatip Saetia
Chulalongkorn University Theses and Dissertations (Chula ETD)
A sentence is typically treated as the minimal syntactic unit used for extracting valuable information from a longer piece of text. However, in written Thai, there are no explicit sentence markers. We proposed a deep learning model for the task of sentence segmentation that includes three main contributions. First, we integrate n-gram embedding as a local representation to capture word groups near sentence boundaries. Second, to focus on the keywords of dependent clauses, we combine the model with a distant representation obtained from self-attention modules. Finally, due to the scarcity of labeled data, for which annotation is difficult and time-consuming, …
A Model Predictive Control Strategy Based On Predicted Mean Vote For A Building Hvac System, Chanthawit Anuntasethakul
A Model Predictive Control Strategy Based On Predicted Mean Vote For A Building Hvac System, Chanthawit Anuntasethakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis proposes a design of a supervisory model predictive controller for a heating-ventilation-air-conditioning (HVAC) control system. The control objective is to minimize the operating cost and take into account of electrical load shaving and thermal comfort of users. To ensure that thermal comfort is well regulated, we utilize the Predicted Mean Vote (PMV) as an indicator and determine an acceptable bound of a desired set-point temperature. The control design consists of two layers, namely, a supervisory control (SC) layer and a model predictive control (MPC) layer. For the SC layer, we explore a configuration including the choice of predesign …
A Comparative Simulation Of Glycerol Steam Reforming With Foam And Conventional Pellet Catalysts In Packed Bed Reactor, Chattharika Phitchayakorn
A Comparative Simulation Of Glycerol Steam Reforming With Foam And Conventional Pellet Catalysts In Packed Bed Reactor, Chattharika Phitchayakorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to study the effect of different catalyst structures to the hydrogen production process with glycerol steam reforming in packed bed reactors via the COMSOL Multiphysics program. 2D pseudo-homogeneous steady-state model of a 6-inch diameter adiabatic reactor has been developed to describe a transport phenomenon inside the packed bed reactors with two different catalyst structures of conventional 1-inch pellet catalyst and 10-30PPI foam catalyst. The simulated results show that the novel foam catalyst improved the process performance in terms of pressure drop and hydrogen yield comparing to the conventional 1-inch pellet catalyst. The reactor packed with the conventional …
Optimal Sizing Of Battery Energy Storage System With Rooftop Pv Generation System, Chawin Prapanukool
Optimal Sizing Of Battery Energy Storage System With Rooftop Pv Generation System, Chawin Prapanukool
Chulalongkorn University Theses and Dissertations (Chula ETD)
With a significant growth of the rooftop photovoltaic systems (PVs) under the behind-the-meter scheme (BTMS), the battery energy storage systems (BESS) have been developed to enhance the performance of rooftop PVs in many aspects, especially the electricity charge savings. The BTMS can be typically classified into three schemes of self-consumption scheme, net-metering scheme, and net-billing scheme. Other than these schemes, the solar power purchase agreement (SPPA) has been developed to be one the most attractive business models. The SPPA is the scheme where the investors propose to directly sell an electricity from rooftop PVs with BESS to the customers without …
An Assessment Of Root Reinforcement On Soil Slope Using Centrifuge And Numerical Modelling, Gayuh Aji Prasetyaningtiyas
An Assessment Of Root Reinforcement On Soil Slope Using Centrifuge And Numerical Modelling, Gayuh Aji Prasetyaningtiyas
Chulalongkorn University Theses and Dissertations (Chula ETD)
The extreme rainfall as an effect of climate change has been considered as the main problem due to landslide hazard. The rainfall can trigger slope failure through the kinetic energy of raindrop and decreasing of soil resistance due to the increasing of pore water pressure. Vegetation is considerably as low cost and environmentally friendly slope reinforcement. The root specifically provides high contribution in strengthen the soil through the root-soil interaction. However, there is a gap between slope reinforcement by root modelling and field assessment result. The gap is an impact of indirect linked between laboratory modelling and existing vegetated slope …
Implementation Of Traffic Engineering With Segment Routing And Opendaylight Controller On Emulated Virtual Environment Next Generation (Eve-Ng), Htain Lynn Aung
Implementation Of Traffic Engineering With Segment Routing And Opendaylight Controller On Emulated Virtual Environment Next Generation (Eve-Ng), Htain Lynn Aung
Chulalongkorn University Theses and Dissertations (Chula ETD)
Internet service providers and enterprise networks face rapid changes and rapid growth of the internet, and the networks become complex in operations to support the strict Service-level Agreements (SLAs) needed applications. Segment Routing (SR) is a source routing technology that overcomes the conventional Multiprotocol Label Switching (MPLS) networks' drawbacks in scalability, flexibility, and applicability in Software-defined Networking (SDN). SR enables the source device to instruct the path using a segment or list of segments to go through the network. SR can be implemented in IPv6 and MPLS. A segment can be defined as information that instructs SR capable nodes to …
Property Estimation Of Palmitoylethanolamide And Sucrose Palmitate For Process Design From Methyl Palmitate, Janetiya Wongprathed
Property Estimation Of Palmitoylethanolamide And Sucrose Palmitate For Process Design From Methyl Palmitate, Janetiya Wongprathed
Chulalongkorn University Theses and Dissertations (Chula ETD)
Methyl palmitate is the primary component of palm oil-based biodiesel. It is a saturated fatty acid methyl ester which has a high melting point that results in low cold flow properties of biodiesel. Besides, lack of government support may affect the revenue of biodiesel business. For that reason, the producers turn attention to using biodiesel as a raw material for the production of value-added chemicals. Initially, we selected the studied products based on the gross profit margin, production process, market demand and application. This work simulated the production of palmitoylethanolamide, sucrose palmitate and normal alkanes from methyl palmitate using Aspen …
A Study Of Customers' Willingness To Purchase Organic Fresh Milk In Thailand, Jeerawan Punwaree
A Study Of Customers' Willingness To Purchase Organic Fresh Milk In Thailand, Jeerawan Punwaree
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, most consumers often are care about health due to the COVID-19 and personal needs. Dairy products are specific products that are generally consumed by every age group, from children, teenagers, adults, to the elderly. Organic milk could provide an advantageous alternative for health conscious consumers as it must be certified by government agencies prior to market launching. There are many studies supported that organic milk is more beneficial than conventional milk. Theory of Planned Behavior (TPB) was applied to study the factors affected consumers' willingness to purchase organic fresh milk in Thailand. Through the questionnaire method and analysis by …
Deep Sequential Real Estate Recommendation Approach For Solving Item Cold Start Problem, Jirut Polohakul
Deep Sequential Real Estate Recommendation Approach For Solving Item Cold Start Problem, Jirut Polohakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
The item cold-start problem occurs when a recommendation system cannot recommend new items owing to record deficiencies and new listing omissions. When searching for real estate, users can register a concurrent interest in recent and prior projects. Thus, an approach to recommend cold-start and warm-start items simultaneously must be determined. Furthermore, unrequired membership and stop-by behavior cause real estate recommendations to have many cold-start and new users. This characteristic encourages the use of a content-based approach and a session-based recommendation system. Herein, we propose a real estate recommendation approach for solving the item cold-start problem with acceptable warm-start item recommendations …
A Morphable Fpga Soft Processor Using Llvm Infrastructure Targeting Low-Power Application-Specific Embedded Systems, Ehsan Ali
Chulalongkorn University Theses and Dissertations (Chula ETD)
The reconfigurable computing (RC) aims to combine the flexibility of General-Purpose Processor (GPP) with performance of Application Specific Integrated Circuits (ASIC). There are several architectures proposed since RC's inception in 1960s, but all have failed to become mainstream. The main factor preventing RC to become common practice is its requirement for implementers of algorithms (programmers) to be familiar with hardware design. In RC, a hardened processor cooperates with a dynamic reconfigurable Hardware Accelerator (HA) which is implemented on Field-Programmable Gate Array (FPGA). The HA implements crucial software kernel on hardware to increase performance and its design demands digital circuit expertise. …
Production Of Γ-Valerolactone (Gvl) From One-Pot Cascade Transformation Of Furfural Over Pt/Zeolite-Based Catalysts, Jukkapan Saengin
Production Of Γ-Valerolactone (Gvl) From One-Pot Cascade Transformation Of Furfural Over Pt/Zeolite-Based Catalysts, Jukkapan Saengin
Chulalongkorn University Theses and Dissertations (Chula ETD)
γ-valerolactone (GVL) is a green renewable resource, which can be used as fuel additives, organic solvent in food industries, pharmaceutical intermediates. The direct production of GVL from furfural in a one-pot transformation is highly desirable in order to minimize the use of solvents, the number of unit operations, and the production cost. The cascade reaction was carried out in a single reactor, using a secondary alcohol as the hydrogen donor with acid catalysts (so-called Meerwein–Ponndorf–Verley reaction). In this work, the transfer hydrogenation of furfural with 2-propanal as a hydrogen donor was investigated on various zeolites including of HY with Si/Al …
Electrochemical Reduction Of Carbon Dioxide To Formate On Bi And Bisn Electrodes Prepared By Electrodeposition On Copper Foil, Jutamas Wasombut
Electrochemical Reduction Of Carbon Dioxide To Formate On Bi And Bisn Electrodes Prepared By Electrodeposition On Copper Foil, Jutamas Wasombut
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, The Bix/Cu electrocatalysts were prepared by electrodeposition of Bi on Cu foil, and the BixSny/Cu electrocatalysts were prepared by electrodeposition of Bi and Sn on Cu foil in deposition solution bath with different Bi3+ ion concentrations of 0.05, 0.1, and 0.2 M (Bi0.05/Cu, Bi0.1/Cu, Bi0.2/Cu), while the Sn2+ ion concentration was constant at 0.025 M (Bi0.05Sn0.025/Cu, Bi0.1Sn0.025/Cu, Bi0.2Sn0.025/Cu). The electrocatalysts were characterized by SEM-EDX, XRD, and XPS and tested in the electrochemical CO2 reduction reaction. The results demonstrate that the Bi concentrations in the deposition bath affect the structure of Bi into different forms, including bulky structure …
Experiment And Numerical Study Of The Charge Decay On The Surface Of Pmma Insulator, Kamonporn Malathip
Experiment And Numerical Study Of The Charge Decay On The Surface Of Pmma Insulator, Kamonporn Malathip
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis presents the measurement and simulation of surface charge decay on a polymethyl methacrylate (PMMA) circular disc. The objective of the thesis is to calculate the surface charge density in the 2-dimensional (2D) and the 3-dimensional (3D) models for comparison with the estimated results obtained from experiments, and to study the mechanisms of charge which depends on the thickness of the dielectric disc. For the experiments, a rod-plane electrode arrangement was used to generate the positive corona discharge on surface of 1-, 2- and 10-mm thick PMMA disc. The measured surface potential was used to calculate the electric field …
A Real Estate Valuation Model Using Boosted Feature Selection, Kankawee Chanasit
A Real Estate Valuation Model Using Boosted Feature Selection, Kankawee Chanasit
Chulalongkorn University Theses and Dissertations (Chula ETD)
To estimate real estate values, a complex valuation model based on artificial neural network (ANN) has been established as a successful means in modern machine learning research, specifically when high-dimensional data are available. Unfortunately, the real estate data in many locations, such as Thailand, are quite limited in terms of features. Hence, it becomes mandatory to reduce the complexity using feature selection techniques. These techniques aim to improve performance by identifying significant factors and help decrease the computational overload and model construction. However, due to the lack of explicability and interpretability in ANNs, the analysis of input factors cannot be …
Selective Hydrogenation Of Acetophenone To 1-Phenylethanol On Pt/ Tio2 Catalysts Prepared By Pulsed Dc Magnetron Sputtering, Khunarnon Ditsataporncharoen
Selective Hydrogenation Of Acetophenone To 1-Phenylethanol On Pt/ Tio2 Catalysts Prepared By Pulsed Dc Magnetron Sputtering, Khunarnon Ditsataporncharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
1-Phenylethanol (PHE) is a high-value chemical with various applications in fragrance and pharmaceutical industries. It is extensively used as strawberry fragrance additives in yogurts and chewing gums and an intermediate of anti-inflammatory drugs such as Ibuprofen. In this study, selective hydrogenation of acetophenone (AP) to PHE was investigated using platinum catalysts supported on different types of titanium dioxide including PC500 (pure anatase) and P25 (anatase mixed rutile). Pt was deposited on the titanium dioxide supports by pulsed direct current magnetron sputtering (PDC-MSD) method with deposition time spent on Pt coating at 3, 6, and 9 minutes. For comparison purposes, Pt/TiO2 …
Explainable Stock Price Prediction Using Technical Indicators With Short Thai Textual Information, Kittisak Prachyachuwong
Explainable Stock Price Prediction Using Technical Indicators With Short Thai Textual Information, Kittisak Prachyachuwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
A stock trend prediction has been in the spotlight from the past to the present. Fortunately, there is an enormous amount of information available nowadays. There were prior attempts that have tried to forecast the trend using textual information; however, it can be further improved since they relied on fixed word embedding, and it depends on the sentiment of the whole market. In this paper, we propose a deep learning model to predict the Thailand Futures Exchange (TFEX) with the ability to analyze both numerical and textual information. We have used Thai economic news headlines from various online sources. To …
Redesigning Weakly Supervised Localization Architectures For Medical Images, Konpat Preechakul
Redesigning Weakly Supervised Localization Architectures For Medical Images, Konpat Preechakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Point localization is a task that aims to identify the location but not the extent of an object of interest in an input image. A success localization is when a model predicts a point which is within the boundary of an object of interest. This task has been successfully learnt using only image-level annotation i.e. image classification. This setting is known as weakly-supervised point localization. Weakly-supervised point localization is particularly useful in medical imaging task where not only the decision of a model is required by also the explanation. The better the explanation the more useful the model is. Usually …
Electrochemical Reduction Of Co2 To Co On Zn Electrodes Prepared By Electrodeposition Method, Krongkwan Poonbun
Electrochemical Reduction Of Co2 To Co On Zn Electrodes Prepared By Electrodeposition Method, Krongkwan Poonbun
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, the effect of substrates including Cu and Ti on the catalytic activity of Zn electrocatalysts prepared by electrodeposition method was investigated in the electrochemical reduction of CO2 (CO2ER). As analyzed by SEM-EDX and XRD results, it indicated that the different substrates did not have any influence on the morphologies of catalysts and the conductivity of substrate was the main factor on the CO2ER performance. The effect of Zn precursor concentration in the range of 0.025 M to 0.4 M was further studied on the characteristics and the activity of Zn/Cu catalysts in the CO2ER. . At low …
Determining The Effectiveness Of The Health-Edrm Framework And Twitter Data Analysis As The Near Real-Time Source Of Information During The Covid-19 Situation, Kumpol Saengtabtim
Determining The Effectiveness Of The Health-Edrm Framework And Twitter Data Analysis As The Near Real-Time Source Of Information During The Covid-19 Situation, Kumpol Saengtabtim
Chulalongkorn University Theses and Dissertations (Chula ETD)
Coronavirus pandemic or COVID-19 pandemic is considered to be one of the most severe disasters that affect both lives and economics to all the countries around the world. Health Emergency and Disaster Risk Management Framework or HEALTH-EDRM framework is the disaster management framework established in late 2019. One objective of this framework is to reduce the impact of the disaster that affects the lives of the people. Risk communication which is considered as the main function of this framework is also the main key for reducing the amount of affecting people. In this research, the analysis of the effectiveness of …
A Comparative Study Of Road Traffic Violation Between Thai And Japanese Students, Napattharakorn Katanararoj
A Comparative Study Of Road Traffic Violation Between Thai And Japanese Students, Napattharakorn Katanararoj
Chulalongkorn University Theses and Dissertations (Chula ETD)
During the last ten years. Accidents of vulnerable road users in Thailand have increased significantly and hit the most severe accident in 2017, especially teenagers between 15-19 year-old. When comparing to Japan in 2017, Japan has reached the lowest accident of all-time since 1960. Considering differences, there are differences in attitudes and behavior toward violation behavior. This study aims to analyze the factor affecting violation behavior between Thai and Japanese to determine the appropriate policies and recommendations. By studying road user's behavior and attitude based on the theory of planned behavior (TPB) in Bangkok, Thailand and Sapporo, Hokkaido, Japan. Questionnaires …
Manufacturing Cost Reduction In A Filling Process Of Aerosol Products, Nattagun Charoenbunsupkarn
Manufacturing Cost Reduction In A Filling Process Of Aerosol Products, Nattagun Charoenbunsupkarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focuses on the development of heuristics that help reduce the production cost of an aerosol filling process of a case study company, while satisfying all related constraints, including production capacity and due dates. The proposed heuristics are a two-phase one, where the initial solutions are first constructed based on simple dispatching rules, and, once completed, such solution is then iteratively improved by two different improvement heuristics, namely 2OPT and Node Shift. A tabu list is also embedded within such a framework to help reduce its computational time. We have assessed the performances of these heuristics based on 6 …