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2018

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Articles 11581 - 11610 of 11756

Full-Text Articles in Physical Sciences and Mathematics

C-O Bond Formation On C-5 Of 2,4-Diaminopyrimidines, Natthakorn Uppatam Jan 2018

C-O Bond Formation On C-5 Of 2,4-Diaminopyrimidines, Natthakorn Uppatam

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work aims to find a robust oxidation condition that can efficiently convert 2,4-diaminopyrimidines to its C5-hydroxylated derivative. Although Boyland-Sims oxidation of these substrates has been reported, this procedure suffers low yield and poor reproducibility. The conditions for Boyland-Sims oxidation of 2,4-diaminopyrimidines were thus re-optimized. The parameters that could affect the yields of the 5-hydroxy products were investigated using 2,4-diamino-6-ethylpyrimidine as a model compound. The reactions were performed at 0.10 mmol scale of the starting pyrimidine. The yields of the products were monitored by 1H NMR spectroscopy with reference to an internal standard. The reaction was reproduced at larger scale …

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Synthesis Of Hydroxyapatite Nanoparticles For Polynucleotides Delivery In Dentistry, Natthaya Thepphanao Jan 2018

Synthesis Of Hydroxyapatite Nanoparticles For Polynucleotides Delivery In Dentistry, Natthaya Thepphanao

Chulalongkorn University Theses and Dissertations (Chula ETD)

Hydroxyapatite (HAp) nanoparticles-based miRNA delivery system has emerged as a promising therapeutic agent for bone regeneration application. In order to achieve high therapeutic performance, the development of HAp functions remains challenging. This study describes the influence of HAp characters on their biological activities with osteoblast cell by synthesized different sizes of rod-like HAp with 150-200 and 100 nm in size and the different shape of elongated particles with 100-150 nm in size. A comparison was carried out on cytotoxicity, cellular uptake, and miRNA binding capacities. The elongated and rod-like shapes of 100-150 nm illustrated the high cell viability, and interestingly, …

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Glycosylation Of Thioglycosides With Bromodiethylsulfonium Bromopentachloroantimonate As Novel Activator, Ladawan Punrum Jan 2018

Glycosylation Of Thioglycosides With Bromodiethylsulfonium Bromopentachloroantimonate As Novel Activator, Ladawan Punrum

Chulalongkorn University Theses and Dissertations (Chula ETD)

Glycosylation is an important reaction in carbohydrate synthesis of complex molecules such as oligosaccharides, glycoproteins, and glycolipids. Thioglycosides are widely used as precursors in oligosaccharide synthesis due to their ease of preparation, high stability towards protecting group manipulations and variety of activation methods. Recently, bromodiethylsulfonium bromopentachloroantimonate (BDSB) was reported as a novel source of highly electrophilic bromine. It was used to efficiently initiate cation-π cyclizations of polyene at low temperature. Herein, we report a chemical glycosylation of thioglycosides activated by BDSB. Firstly, armed and disarmed glycosyl donors and glycosyl acceptors were synthesized by using modified previous method. Next, several reaction …

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Metalloporphyrin-Sensitized Titania/Silica/Iron Oxide Nanocomposites And Their Photocatalytic Activities, Padtaraporn Chanhom Jan 2018

Metalloporphyrin-Sensitized Titania/Silica/Iron Oxide Nanocomposites And Their Photocatalytic Activities, Padtaraporn Chanhom

Chulalongkorn University Theses and Dissertations (Chula ETD)

New nanomaterials of the magnetic visible light active photocatalysts, tetra(4-carboxyphenyl)porphyrin (TCPP) with different metals [Mn(II), Fe(III), Cu(II), Zn(II) and metal-free] in the center adsorbed on titania-silica-iron oxide superparamagnetic composites (TSI) were synthesized successfully. The photocatalytic activities in methylene blue (MB) degradation were determined under incandescent lamp for 3 h. Their characteristics have been identified using UV-visible spectroscopy, X-ray diffractometry (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The photodegradation results revealed that the metalloporphyrin sensitization helped TSI to absorb the light in visible region. Titania-silica-iron oxide nanomaterials with copper(II) tetra(4-carboxyphenyl)porphyrin (CuTCPP) can significantly …

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Molecular Simulations Of Voltage-Gated Proton-Selective Channel, Panisak Boonamnaj Jan 2018

Molecular Simulations Of Voltage-Gated Proton-Selective Channel, Panisak Boonamnaj

Chulalongkorn University Theses and Dissertations (Chula ETD)

Voltage-gated proton-selective channels (Hv1) are a membrane protein that permeates proton across cell membranes. They play an important role in various physiological processes. Hv1 was found as a dimer in membranes. Molecular mechanisms underlying the proton conduction of Hv1 have been a subject of intense research but is still remained unclear. In this study, molecular dynamics (MD) simulations of Hv1 were carried out to gain better understanding of the structure-function relationship. The first part of this thesis involved with an investigation of the role of the C-terminal domain (CTD) in stabilizing the dimer structure of Hv1. MD data showed the …

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Fluorescent Sensors From Salicylaldimine Derivatives For Metal Ions, Phoom Sangsuwan Jan 2018

Fluorescent Sensors From Salicylaldimine Derivatives For Metal Ions, Phoom Sangsuwan

Chulalongkorn University Theses and Dissertations (Chula ETD)

An in-situ forming and sensing was developed as a high-throughput screening of fluorescent chemosensors for metal ions. The 45 salicylaldimines, formed in-situ from the condensation between 5 salicylaldehydes and 9 amines, in 96 well-plates were photographed under black light along with the 5 salicylaldehydes in the absence and presence of 18 metal ions. The library of fluorescence response images of these 50 chemosensors were processed into RGB values. The PCA of theΔRGB, the differences between those of images with and without the metal ions, showed 9 sensors with normalized loading value over 70%. The sensor array constructed from these 9 …

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Hybrid Materials From Covalent Organic Frameworks And Ionic Liquids, Ranida Maliyaem Jan 2018

Hybrid Materials From Covalent Organic Frameworks And Ionic Liquids, Ranida Maliyaem

Chulalongkorn University Theses and Dissertations (Chula ETD)

Covalent organic frameworks (COFs) are new type material, whereby their wide range of properties derived from the chemistry of frameworks and their regular porosity. Here in, we reported the successful syntheses of the novel hybrid materials between porous COF material and ionic liquids (ILs). The crystalline porous powder of boroxine‑based COF, so called COF‑5, is reproducible via a condensation reaction between hexahydroxyltriphenylene and phenyldiboronic acid under a mild condition using a conventional heating method. The as‑synthesized COF-5 was characterized with PXRD, FT-IR, TGA and BET techniques, showing that the material contained 1D regular channels caused by π-π stacking of the …

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Detection Of Sulfonamide Residues By Paper Spray Mass Spectrometry, Surased Suraritdechachai Jan 2018

Detection Of Sulfonamide Residues By Paper Spray Mass Spectrometry, Surased Suraritdechachai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Sulfonamide antibiotics are commonly used veterinary drugs in livestock to prevent or treat infectious diseases. Their residues in food are of concern since they can cause adverse health effects and development of bacterial resistance. In this work, a practical method for detection and quantification of sulfamethazine, one of sulfonamide antibiotics, in pig body fluid samples is developed via the combination of simple extraction and paper spray mass spectrometry. The method required minimal sample preparation and low analysis time while providing high sensitivity and accuracies in pig whole blood (LOD = 10.1 ng/mL, %recovery = 95.4-104.1%), pig serum (LOD = 4.6 …

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Fabrication And Mechanical Properties Of Hyaluronic Acid Microneedle Arrays For Transdermal Drug Delivery, Teeranut Rutwaree Jan 2018

Fabrication And Mechanical Properties Of Hyaluronic Acid Microneedle Arrays For Transdermal Drug Delivery, Teeranut Rutwaree

Chulalongkorn University Theses and Dissertations (Chula ETD)

Dissolvable microneedles have been widely investigated as an alternative of hypodermic injection or other drug delivery methods. Various polymers have been used to fabricate microneedles. Type of polymers affects mechanical properties and dissolution rate of microneedles. In this study, five formulations of hyaluronic acid (HA)/ polyvinylpyrrolidone (PVP) composite microneedle patches (HA/PVP at 100/0, 75/25, 50/50, 25/50, 0/100) were fabricated. The crosslinked HA microneedles were also fabricated. Mechanical properties of the obtained microneedles were determined by universal testing machine and durometer. The skin-penetration ability and dissolution rate of HA/PVP microneedles were also investigated using porcine skin. The results show that microneedle …

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Synthesis Of Halogenated Flavonoids As Anti-Dengue Agents, Thao Huynh Nguyen Thanh Jan 2018

Synthesis Of Halogenated Flavonoids As Anti-Dengue Agents, Thao Huynh Nguyen Thanh

Chulalongkorn University Theses and Dissertations (Chula ETD)

Flavonoids have been recognized as promising compounds with various bioactivities. Certain flavonoid derivatives exhibited more potent activities than their parent compounds. Recently, halogenated flavonoids have been addressed for their anti-dengue activity. In this research, a series of twenty-two brominated and iodinated flavonoid derivatives were synthesized and explored for dengue infection inhibition. Seventeen derivatives have been investigated for the first time. 8-Bromobaicalein, 6,8-dibromopinocembrin, 6,8-dibromopinostrobin, 6,8-diiodopinostrobin were disclosed as effective and non-toxic anti-dengue agents. These compounds displayed remarkably low EC50 as well as high CC50, which could be considered as potent therapeutic agents. Moreover, the preliminary screening on brominated O7-ether chrysins discovered …

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Benzimidazole Derivatives Of Perylene Diimide For Organic Field-Effect Transistor, Tianchai Chooppawa Jan 2018

Benzimidazole Derivatives Of Perylene Diimide For Organic Field-Effect Transistor, Tianchai Chooppawa

Chulalongkorn University Theses and Dissertations (Chula ETD)

The poor solubility of perylene derivatives has been a key factor that prohibits the application of these thermally stable compounds in organic field-effect transistors (OFET) devices. In this research, the effort to enhance the solubility and exploring FET property of benzimidazole derivatives of perylene diimide were investigated. The perylene diimide core structure was functionalized by aryloxy moieties. Unfortunately, the isomeric products were still poorly soluble in common organic solvents, which made them impossible to separate and purify. Thus, the synthetic plan and goal were completely revised to the benzotriazatruxene derivatives, which were highly soluble in organic solvents such as dichloromethane …

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Green Synthesis Of Gold Nanoparticles Using Natal Lily Crinum Moorei Extract And Biological Activities, Warinda Marujiwat Jan 2018

Green Synthesis Of Gold Nanoparticles Using Natal Lily Crinum Moorei Extract And Biological Activities, Warinda Marujiwat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Crinum moorei as medical herb has different pharmacological activities such as anti-cancer and anti-inflammatory properties. Gold nanoparticle (AuNP) is an interesting anti-cancer drug carrier which can solve anti-cancer drug's problems with good biocompatibility, non-toxicity and suitable size for the intracellular uptake to treat to the target cells. From the beginning, other reducing agents were used to synthesize AuNPs. However, they lead to the contamination of chemicals on AuNP's surfaces which limits the medical application or long process and time consuming. Therefore, plant extracts were studied to make a remarkable dual function: the synthesized AuNPs agent and drug agent. In this …

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Development Of Headspace-Solid Phase Microextraction And Gas Chromatography-Mass Spectrometry/Olfactometry For Analysis Of Volatile Compounds From Chicken Products, Wongkanok Yoosong Jan 2018

Development Of Headspace-Solid Phase Microextraction And Gas Chromatography-Mass Spectrometry/Olfactometry For Analysis Of Volatile Compounds From Chicken Products, Wongkanok Yoosong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Gas chromatography-mass spectrometry/olfactometry coupled headspace solid phase microextraction (HS-SPME-GC-MS/O) was applied to analysis of volatile compounds from raw chickens and boiled chickens. The HS-SPME was 50/30 mm DVB/CAR/PDMS. The extraction temperature of boiled chicken was 50 °C for 30 min and raw chicken were extracted at room temperature. The SPME Probes were analyzed by GC-MS with a HP-5MS capillary column. 16 volatile compounds were identified in the boiled chickens in four chemical classes including aldehydes, aromatic hydrocarbon, alcohols and ketones and 20 volatile compounds were identified in raw chickens in three chemical classes including aldehydes, alcohols and esters. The identification …

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Synthesis And Antidiabetic Activity Of Furofuran Lignans Containing Multiphenolic Groups, Titiruetai Doungwichitrkul Jan 2018

Synthesis And Antidiabetic Activity Of Furofuran Lignans Containing Multiphenolic Groups, Titiruetai Doungwichitrkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Synthesis of furofuran lignans containing multiphenolic groups (6-12) was carried out. The starting material samin (5) was obtained by acid hydrolysis of sesamin (2), which was isolated from sesame seed oil. A series of target lignans were synthesized from samin (5) and a varity of phenolics through Friedel-Crafts reaction, yielding desired products (6). To increase number of hydroxy moieties on the synthesized lignans, oxidative reaction using lead (IV) tetraacetate was performed. Removal of methylenedioxy of furofuran lignans containing a phenolic moiety produced unexpected products which contains para-quinone together with ortho-dihydroxy moieties on furofuran core structures (8-9). Consequently, to avoid oxidation …

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A Deep Relation Extraction From Biomedical Texts With Attention Mechanisms And Domain-Specific Contextual Representations, Amarin Jettakul Jan 2018

A Deep Relation Extraction From Biomedical Texts With Attention Mechanisms And Domain-Specific Contextual Representations, Amarin Jettakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

The biomedical relation extraction (RE) tasks aim to study the interaction between pre-defined entities from biomedical literature: Bacteria Biotope (BB) and Drug-Drug interactions (DDI) tasks. Some previous investigations have used feature-based models; others have presented deep-learning-based models such as convolutional and recurrent neural networks used with the shortest dependency paths (SDPs). Although SDPs contain valuable and concise information, sections of significant information necessary to define bacterial location relationships are often neglected. In addition, the traditional word embedding used in previous studies may suffer from word ambiguation across linguistic contexts. Here, we present a deep learning model for biomedical RE. The …

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Knowledge Sharing In Cooperative Compact Genetic Algorithm, Orakanya Gateratanakul Jan 2018

Knowledge Sharing In Cooperative Compact Genetic Algorithm, Orakanya Gateratanakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

The compact genetic algorithm is derived from the genetic algorithm in which the population is represented by the probabilistic vector. To improve the search capability and avoiding local minima, parallelization has been employed where many search processes are deployed concurrently. In order to coordinate the work of multiple processes, knowledge sharing is necessary. Multiple processes share their probabilistic vectors partially. To escape from local minima the restart step is introduced. The experiment compares the proposed algorithm with two other competitive algorithms using Traveling Salesman problem, Bin Packing problem, Subset Sum problem, and Knapsack problem. The results show that the proposed …

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Explicit Energy-Minimal Short-Term Path Planning For Collision Avoidance In Bidirectional Crowd Simulation, Saran Sillapaphiromsuk Jan 2018

Explicit Energy-Minimal Short-Term Path Planning For Collision Avoidance In Bidirectional Crowd Simulation, Saran Sillapaphiromsuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

การหาเส้นทางการเดินในระยะยาวรวมกับการหลบหลีกสิ่งกีดขวางรอบๆ เป็นวิธีทั่วไปที่ถูกนำมาใช้ในการจำลองการเคลื่อนไหวของตัวตนจำลองจากตำแหน่งหนึ่งไปยังอีกตำแหน่งหนึ่ง โดยไม่ให้เกิดการชนกันระหว่างตัวตนจำลองกับวัตถุในฉากและระหว่างตัวตนจำลองด้วยกันเอง วิธีนี้สามารถให้ผลการจำลองที่ดีในสถานการณ์ที่ผู้คนสามารถเดินได้หลายทิศทาง แต่ในสถานการณ์ที่ผู้คนถูกจำกัดทิศทางการเดินให้เหลือเพียงหนึ่งหรือสองทิศทางนั้น ปรากฏว่าตัวตนจำลองมีลักษณะการเดินที่ผิดธรรมชาติ เช่น เดินเข้าไปติดและอยู่นิ่งระหว่างตัวตนจำลองสองตัวที่เดินสวนมาหรือเดินเข้าไปในพื้นที่ที่แออัดหรือมีกลุ่มคนเยอะๆ ทั้งๆที่ยังมีเส้นทางเดินที่ทำให้ตัวตนจำลองสามารถเดินหลบหลีกไปได้ ลักษณะเช่นนี้เกิดขึ้นบ่อยและเห็นได้ชัดในสถานการณ์แบบสองทิศทาง งานวิจัยนี้จึงได้เสนอขั้นตอนในการหาเส้นทางในระยะสั้นเพื่อขจัดความบกพร่องของพฤติกรรมการเดินของตัวตนจำลองในสถานการณ์แบบสองทิศทางนี้ขึ้น โดยใช้สมการพลังงานทางชีวกลศาสตร์ของการเดินเข้ามาเป็นตัวแปรที่บังคับให้ตัวตนจำลองมีความฉลาดในการเลือกเส้นทางในระยะสั้นได้ ผลลัพธ์ของการวิเคราะห์สมการพลังงานนั้น ช่วยบ่งบอกลักษณะของการเลือกเส้นทางการเดินที่ดีที่สุด โดยคำนึงถึงความเร็วที่ใช้เพื่อให้ประหยัดพลังงานที่สุด พร้อมๆ กับถึงจุดหมายปลายทางให้เร็วที่สุดด้วย นอกจากนี้ยังพบว่าการนำวิธีที่เสนอนี้ไปใช้ในสถานการณ์แบบหลายทิศทางนั้น ตัวตนจำลองสามารถหาเส้นทางที่เหมาะสมกว่าเมื่อเทียบกับวิธีก่อนอีกด้วย ยกตัวอย่าง เช่น ตัวตนจำลองสามารถเดินแทรกเข้าไปในช่องแคบๆ ของขบวนพาเหรดได้ เป็นต้น

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Development Of Eeg-Based Emotion Classification Using Deep Learning Networks, Suwicha Jirayucharoensak Jan 2018

Development Of Eeg-Based Emotion Classification Using Deep Learning Networks, Suwicha Jirayucharoensak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Emotion classification is one of essential tasks for Human Computer Interaction (HCI) to make computers more efficiently interact with their users. Electroencephalogram (EEG) signals, associated with cognitive states of emotions, propagate though a complex hierarchy of neuron cells. Therefore, EEG-based emotion classification requires sophisticated learning algorithms that can represent high-level abstraction of a complicated task. This dissertation focuses on applying deep learning networks (DLNs) to enhance accuracy performance of the EEG-based emotion classification system. The DLN provides hierarchical feature learning methodology which is suitable for EEG-related feature learning algorithms. Furthermore, this research investigates the effects of temporal neural dynamics of …

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Multi-Paths Quest Generation For Structural Analysis, Thongtham Chongmesuk Jan 2018

Multi-Paths Quest Generation For Structural Analysis, Thongtham Chongmesuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

Existing quest generation systems that used quest structures had an important limitation. They were not compatible with dynamic environment games, where player actions may have unforeseen repercussion from chain-reaction, such as locking the quest or preventing it from being completed. In addition, quests generated by such systems were not guaranteed to have multiple completion paths.
In this thesis, action-based-objective quests were replaced with game state-based-objective quests, while retaining the previous grammar rule. Each quest's contents and objectives were filled using Token system and Full Condition State system to ensure the connectivity within the quest's contents and to prevent players from …

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Fully Automatic 3d Facial Cosmetic Surgery Simulation, Adawat Chanchua Jan 2018

Fully Automatic 3d Facial Cosmetic Surgery Simulation, Adawat Chanchua

Chulalongkorn University Theses and Dissertations (Chula ETD)

Before cosmetic surgery procedures, the patients are commonly involved in the consultation process using interviews and reference images. The reference images typically consist of pre-post surgery images of other patients, leading to misunderstandings between patients and the surgeon. This thesis presents a fully automatic pipeline to simulate the whole face of post-surgery results. We first establish a 3D face registration and alignment based on the face surgery procedures of the current day and then generate the delta image. We proposed the delta image to solve the lack of dataset dilemma of the pre-post surgery face images. We also propose a …

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Failure Prediction In Open-Hole Wireline Logging Of Oil And Gas Drilling Operation Using Support Vector Machine., Maylada Pootisirakorn Jan 2018

Failure Prediction In Open-Hole Wireline Logging Of Oil And Gas Drilling Operation Using Support Vector Machine., Maylada Pootisirakorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

The failure of open-hole wireline logging leads to an unexpected cost and time that add to drilling operation. The research proposes methods to predict the failure of an open hole wireline logging prior to run the log on actual situation. Three machine learning techniques are used to classify the result of the open-hole wireline logging from drilling process into two classes, a success class and a failure class which represents a well that might have abnormal conditions which can causes the tool stuck during logging. The success class is the normal well that can run logging to target depth without …

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A Scalable Shapelet Discovery For Time Series Classification, Nattakit Vichit Jan 2018

A Scalable Shapelet Discovery For Time Series Classification, Nattakit Vichit

Chulalongkorn University Theses and Dissertations (Chula ETD)

As time series data become more complex and users expect more sophisticated information, numerous algorithms have been proposed to solve these challenges. Among those algorithms to classify time series data, shapelet – a discriminative subsequence of time series data – is considered a practical approach due to its accurate and insightful classification. However, previously proposed shapelet algorithms still suffer from exceedingly high computational complexity, as a result, limiting its scalability to larger datasets. Therefore, in this work propose a novel algorithm that speeds up shapelet discovery process. The algorithm so called "Dual Increment Shapelets (DIS)" is a combination of two-layered …

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Spark Steaming Framework For Large-Scale Multi-Stream Data Analytics, Tanwa Sirisakdiwan Jan 2018

Spark Steaming Framework For Large-Scale Multi-Stream Data Analytics, Tanwa Sirisakdiwan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Real-time streaming applications with multiple heterogeneous data streams have become increasingly popular especially in IoT applications where huge amount of sensors produce large amount of data in the form of data streams. However, many issues still exist, especially in deploying and maintaining these large amounts of data streams. Using Spark Structured Streaming, this research introduces a Spark Streaming framework for multiple heterogeneous data streams which focuses on the ease of deployment and proper scheduling. Our proposed framework is a library that allows the deployment of multiple heterogeneous data stream processing in a single Spark application. Our framework can reduce deployment …

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Classification Of Risk Attitudes From Customer Behavior With Machine Learning, Teeranai Sriparkdee Jan 2018

Classification Of Risk Attitudes From Customer Behavior With Machine Learning, Teeranai Sriparkdee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Every​ product​ and service in​ the market​ has​ its​ characteristic​ which has an impact on a consumer's decision to buy or use them. The risk is a special characteristic of financial products, so in financial product and service design must use risk as a critical factor. On the other hand, the consumer has different attitudes to the risk which can distinguish in 3 categories viz risk aversion, risk neutral and risk seeking. Therefore, knowing risk attitudes of consumer who is the target market is an important key to define marketing strategy such as designing service and product, campaign, and promotion …

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Lightly-Supervised Learning Methods For One-Class Text Classification, Yiping Jin Jan 2018

Lightly-Supervised Learning Methods For One-Class Text Classification, Yiping Jin

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis introduces a lightly-supervised learning method to train text classifiers with very little manual labelling effort. We adapt two previous state-of-theart lightly-supervised models, generalized expectation (GE) criteria (Druck et al. (2008)) and multinomial naïve Bayes (MNB) with priors (Settles (2011)) to oneclass classification problem. Users just need to label a handful of keywords for the target category. We also combine the two aforementioned models by letting MNB automatically augment the list of GE constraints. In addition, we ensemble two families of classifiers to improve the accuracy further. We successfully applied our model to a real-world problem of online advertising. …

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A Hotel Hybrid Recommendation Method Based On Context-Driven Using Latent Dirichlet Allocation, Weraphat Nimchaiyanan Jan 2018

A Hotel Hybrid Recommendation Method Based On Context-Driven Using Latent Dirichlet Allocation, Weraphat Nimchaiyanan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Recommender systems play an important role in helping users find items that they want. Normally, ratings are used in content-based filtering (CBF) and collaborative filtering (CF) for recommendation. However, only ratings are not enough for recommendation. Thus, contextual information, context driven and Latent Dirichlet Allocation (LDA) are used to improve recommendation. Also, the context of individual user has changed in the timeline (context-driven). In this work, a hotel hybrid recommendation method (CF+CBF) based on context-driven using LDA is proposed. Firstly, we find missing user ratings of user-hotel rating matrix by applying LDA on user ratings in order to get predicted …

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Using N-Alkane As A Proxy To Reconstruct Paleoenvironment In Thale Noi, Phatthalung Province, Assuma Sainakum Jan 2018

Using N-Alkane As A Proxy To Reconstruct Paleoenvironment In Thale Noi, Phatthalung Province, Assuma Sainakum

Chulalongkorn University Theses and Dissertations (Chula ETD)

Normal alkane (n-alkane) is the widely used hydrocarbon proxy for the paleoenvironmental study because of their specific characteristic and resistance to microbial degradation. The n-alkanes from the sediment cores TLN-CP5 and TLN-CP7 from Thale Noi, Phatthalung Province, were analyzed and subsequently compared with those derived from the recent plant samples. The plant samples were taken from mangrove forests, i.e. true mangrove, back mangrove, and mangrove associate, based on the previous study on pollen analysis. The n-alkane distributions, the average chain length (ACL), the carbon preference index (CPI) and the proportion of aquatic components (Paq) were further analyzed in order to …

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Lithological Classification By Deep Learning Algorithm, Worapop Thongsame Jan 2018

Lithological Classification By Deep Learning Algorithm, Worapop Thongsame

Chulalongkorn University Theses and Dissertations (Chula ETD)

Six machine learning algorithms are used to classify subsurface rocks based on fifteen well logging features from four geothermal wells in the Snake River Plain, Idaho, USA. Two experimental designs, single- and multiple-well tests, are developed to determine the most optimal model and hyperparameters. The single-well test randomly assigns the data in each well into 70% for training set, 10% for validation set, and 20% for test set. The multiple-well test combines data from three wells and splits the data in the fourth well into 70% for training set, 10% for validation set, and 20% for test set. Results show …

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Rethinking Inclusive And Sustainable Educational Development For Moken Children, Jason Sanglir Jan 2018

Rethinking Inclusive And Sustainable Educational Development For Moken Children, Jason Sanglir

Chulalongkorn University Theses and Dissertations (Chula ETD)

Despite numerous education readjustments, efforts for equal opportunity in education, and an increase in present enrollment, many indigenous children in Thailand continue to fall behind in the formal education system. This study focuses on the Moken Chao Lay (sea people) communities in southern Thailand and looks to analyze and understand situations and shortcomings of Moken children's education and why they are still underperforming in the formal education system. Traditional ways of knowing, especially knowing through nature, are used as a platform to rethink the way we look at indigenous children's education in Thailand. Interview data was collected from school teachers, …

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Selected Appropriate Decision Support Tool For Sustainable Rain-Fed Agriculture Referenced To The New Theory Of His Majesty King Bhumibol Adulyadej The Great: A Case Study Of Khao Wong District, Kalasin Province Of Thailand, Anutra Wannaviroj Jan 2018

Selected Appropriate Decision Support Tool For Sustainable Rain-Fed Agriculture Referenced To The New Theory Of His Majesty King Bhumibol Adulyadej The Great: A Case Study Of Khao Wong District, Kalasin Province Of Thailand, Anutra Wannaviroj

Chulalongkorn University Theses and Dissertations (Chula ETD)

Thailand is an agricultural country of which almost 80% of the total agricultural land is rain-fed. An on-farm pond, which is a self-reliant small-scale water source for harvesting the rainwater to be used for the whole year, becomes radical for farmers in this area. These farmers need to select the agricultural water management scheme which uses limited rainwater harvested in the on-farm pond efficiently and productively to fulfill their household needs, which will lead to sustainable rain-fed agriculture. Therefore, the study aimed to select an appropriate decision support tool for sustainable rain-fed agriculture referenced to the New Theory of His …

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