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Articles 991 - 1020 of 1876
Full-Text Articles in Physical Sciences and Mathematics
Artificial Intelligence And Copyright Law In Singapore A Study On The Protection Of Compilations And Databases Arranged By Ai-Systems, Sella Say
Chulalongkorn University Theses and Dissertations (Chula ETD)
While the capability of artificial intelligence ("AI") gains remarkable momentum in creating copyrightable materials – the questions regarding the eligibility of these new creations, at the moment, are broadly discussed and posed challenges to the regime. The problem of how we fit the conventional notion of authorship and the condition of originality for AI-generated works remains a controversial topic. Some might suggest that subject matter created by AI should not be granted copyright protection on the presumption that AI is not a human who could treat as authors of works. At the same time, other supportive claims that the first …
โมไบล์แอปพลิเคชันสำหรับการค้นหาและจัดการกลุ่มผู้เล่นแบดมินตัน, สุทธิพงษ์ แซ่อื้อ
โมไบล์แอปพลิเคชันสำหรับการค้นหาและจัดการกลุ่มผู้เล่นแบดมินตัน, สุทธิพงษ์ แซ่อื้อ
Chulalongkorn University Theses and Dissertations (Chula ETD)
กีฬาแบดมินตันเป็นกีฬาที่ต้องเล่นอย่างน้อย 2 คนขึ้นไป และต้องมีสนามแบดมินตันในการเล่น ซึ่งปัญหาสำหรับคนที่ต้องการเล่นแบดมินตันอันดับต้นๆ ก็คือ ไม่สามารถหากลุ่มในการเล่นได้ หรือ ไม่สามารถหาสนามแบดมินตันได้ ในปัจจุบันผู้เล่นแบดมินตันมีการรวมกลุ่มการเล่น ที่นัดกันผ่านสื่อสังคม โดยจะเล่นที่สนามแบดมินตันประจำที่หัวหน้ากลุ่มเป็นสมาชิกอยู่ ในช่วงเวลาที่ตกลงกันไว้ล่วงหน้าแบบหลวมๆ ผู้เล่นใหม่จะไม่ทราบถึงกลุ่มการเล่นที่มีอยู่แล้ว จนกว่าจะได้รับการชวนให้เข้ากลุ่มที่นัดเล่นในเวลาที่ตนว่าง ดังนั้นเพื่อช่วยให้ผู้เล่นแบดมินตันกลุ่มต่างๆ และผู้เล่นแบดมินตันรายใหม่สามารถนัดเล่นแบดมินตันที่สนามแบดมินตันได้สะดวก จึงจำเป็นต้องมีระบบที่จะเข้ามาช่วยในการค้นหาและจัดการการเล่นแบดมิน โครงการ “โมไบล์แอปพลิเคชันสำหรับการค้นหาและจัดการกลุ่มผู้เล่นแบดมินตัน” ประกอบด้วย 6 ระบบ ได้แก่ ระบบจัดการบัญชีผู้ใช้ ระบบจัดการกลุ่มผู้เล่นแบดมินตัน ระบบนัดหมาย ระบบจัดการการเล่นแบดมินตัน ระบบออกรายงานและระบบวิเคราะห์การใช้งานสนามของสมาชิกคอร์ท โดยใช้ ไฟร์เบส ในการจัดการฐานข้อมูล ใช้โปรแกรม แอนดรอยด์สตูดิโอ 4.0.1 เป็นเครื่องมือในการพัฒนาระบบและใช้โปรแกรม ไมโครซอฟท์ เพาเวอร์ บีไอ เป็นเครื่องมือในการพัฒนาธุรกิจอัจฉริยะ ระบบที่พัฒนาขึ้นนี้จะช่วยให้การจัดการกลุ่มผู้เล่นแบดมินตันได้อย่างเป็นระบบ มีการจัดเก็บข้อมูลเพื่อนำมาใช้ในการวิเคราะห์และสนับสนุนการตัดสินใจต่างๆให้มีประสิทธิภาพและสร้างความสามารถทางการแข่งขันให้กับเจ้าของสนามแบดมินตันได้
Development Of Authentication-Based Captcha Mechanism On Touch Screen Environment, Nilobon Nanglae
Development Of Authentication-Based Captcha Mechanism On Touch Screen Environment, Nilobon Nanglae
Chulalongkorn University Theses and Dissertations (Chula ETD)
CAPTCHA is a simple security test that was introduced to distinguish among humans and bots for decades. CAPTCHAs have been widely used on commercial sites, such as email service, and social networking sites, for protecting the system from automated software attackers. However, various techniques have been invented to break CAPTCHA, and one of these techniques is the 3rd party attacks. So, the design of CAPTCHA is unable to distinguish between human users and illegitimate human attackers. Thus, this research proposed a new type of CAPTCHA that is individually generated for an individual user. The proposed technique merges between biometrics and …
Building Detection From Remote Sensing Images Using Yolo, Noppadon Pumpong
Building Detection From Remote Sensing Images Using Yolo, Noppadon Pumpong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Building detection system through the remote sensing of images has been widely studied. In this thesis, we propose a model for detecting buildings at airports in Asia through different levels of remote sensing image. The proposed model is improved using the You Only Look Once (YOLO) algorithm based on the convolutional neural network (CNN). We also adjust an inputted image to our model using the Jet Saliency Map. The buildings to be detected in this study are the passenger terminals, the control towers, the cargo buildings, and the hangars. The data set has been collected from 322 different airports in …
Design And Synthesis Of Modified Chitosan/Collagen Coated-Gold Nanoparticles As A Carrier For Anticancer And Antiinflammatory Agents, Naruthai Hongsa
Design And Synthesis Of Modified Chitosan/Collagen Coated-Gold Nanoparticles As A Carrier For Anticancer And Antiinflammatory Agents, Naruthai Hongsa
Chulalongkorn University Theses and Dissertations (Chula ETD)
The proposes of this research are to improve the delivery efficiency of AuNPs. One of the problems with drug loading and drug degradation, the drug was loaded onto the surface of the gold particles, adheres to the outer of the surface, which was easy to decompose in the body. In this work, we have developed the coated AuNPs by modified chitosan (Bi-QCS), which the Biotin-Quat188-AuNPs@collagen (Bi-QCS-AuNPS@collagen) was designed as follow: (i) collagen was used as a reducing agent and a stabilizing agent in the AuNPs@collagen, while (ii) modified chitosan (positive charge polymer) was coated on the outer layer, which modified …
Cops And Robbers On Hypergraphs, Pinkaew Siriwong
Cops And Robbers On Hypergraphs, Pinkaew Siriwong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Cops and robbers game is a game usually played on a finite connected graphwith two players, cop and robber. Recently, cops and robbers game played on hypergraphs was introduced. To give a better chance to a cop by allowing morethan one cop and at least one cop has to move, the cop-number, the least numberof cops to guarantee that they win the game, on graphs and hypergraphs is studied.This thesis provides (i) a characterization of a cop-win hypergraph (ii) some results on the products of hypergraphs and (iii) the cop-number of complete k-partite hypergraphs and n-prisms over a hypergraph. Moreover, …
Stratigraphy And Geochemistry Of Rock Salt From Maha Sarakham Formation In Changwat Chaiyaphum, Northeastern Thailand, Pranot Rattana
Stratigraphy And Geochemistry Of Rock Salt From Maha Sarakham Formation In Changwat Chaiyaphum, Northeastern Thailand, Pranot Rattana
Chulalongkorn University Theses and Dissertations (Chula ETD)
Maha Sarakham Formation is one of massive potash deposits in the Khorat Plateau extending from northeastern of Thailand to central of Lao PDR. Maha Sarakham Formation consists of three rock salt members (the lower, middle and upper members) interbedded with claystone. Potash minerals are associated with the thick bed of rock salt in the upper part of lower salt member. Previous studies are still under discussion on whether the origin of rock salt from marine or non-marine (hydrothermal origin and mixed fluids) deposit. The purpose of this study is to analyze the origin of rock salt based on elemental compositions …
Fusulinacean Biostratigraphy And Carbonate Petrography Of Khao Khwang And Khao Khad Formations, Saraburi Province, Sutharat Sirot
Fusulinacean Biostratigraphy And Carbonate Petrography Of Khao Khwang And Khao Khad Formations, Saraburi Province, Sutharat Sirot
Chulalongkorn University Theses and Dissertations (Chula ETD)
These research purposes are to study petrography, fusulinids assemblage and age and study biostratigraphy correlation of Khao Khwang and Khao Khad Formations, Saraburi province. The fusulinids from the study area belong to 5 families, 11 subfamilies, 15 genera and 15 species including Robustoschwagerina, Yangchienia, Parafusulina loeyensis, Parafusulina gigantea, Laosella edoensis, Pseudofusulina, Chusenella chihsiaensis, Chusenella (Chusenella) shengi, Verbeekina verbeeki, Misellina, Pseudodoliolina, Thailandina buravasi, Neoschwagerina megasphaerica, Colania douvillei, Lepidolina shiraiwensis, Presumatrina ciryi, Sumatrina annae and Sumatrina cf. longissima. These fusulinids indicated that Khao Khad Formation was deposited oldest in Sakmarian to Yakhtashian and youngest in Midian age and Khao Khwang Formation was …
Inspection And Evaluation Of Air Filled Void Inside Reinforced Concrete Structure By Non-Destructive Testing Methods, Thanakit Klomkliew
Inspection And Evaluation Of Air Filled Void Inside Reinforced Concrete Structure By Non-Destructive Testing Methods, Thanakit Klomkliew
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, almost infrastructure in Thailand are almost reinforced concrete (RC) structure because they are strong and durable enough against environmental changes; nevertheless, the concrete durability will be decreased. The proper concrete integrity survey for potential remedy works is very importance, Thus, this research aims to inspect flaws especially delamination and air-filled void by four Non-Destructive Testing (NDT) methods be composed of 1) ultrasonic pulse velocity (UPV), 2) ultrasonic pulse echo (UPE), 3) impact echo (IE), and 4) ground penetrating radar (GPR). Furthermore, this research is separated two parts be consisted of idealized structures simulated defects and a realistic structure. The …
Stochastic Differential Equation Models On Sphere For Animal Migration, Viput Puttanugool
Stochastic Differential Equation Models On Sphere For Animal Migration, Viput Puttanugool
Chulalongkorn University Theses and Dissertations (Chula ETD)
Animal migration is a seasonal movement of a bundle of animals from place to place. A migration cycle is often annually and closely linked with the cyclic pattern of seasons. A short-distance migration can be modeled on a planar surface, but most animals have long-distance migrations, e.g., Arctic terns migrate from the North Pole to the South Pole; thus, their migration should be modeled on a spherical surface. In addition, the Brownian motion term is included in a model to represent noises and randomness of movements. This work aims to simulate their migration routes using stochastic differential equations (SDEs) on …
Mineral Inclusions In Sapphire From Basalt - Related Deposit In Southern Vietnam, Vu Doan Thi Anh
Mineral Inclusions In Sapphire From Basalt - Related Deposit In Southern Vietnam, Vu Doan Thi Anh
Chulalongkorn University Theses and Dissertations (Chula ETD)
Sapphires in Southern Vietnam have been discovered in alluvial deposit derived from Cenozoic basalts. Sample collections for this study were taken from the most significant gem fields including Pleiku, Dak Nong, Di Linh, Binh Thuan, and Krong Nang. Several syngenetic mineral inclusions in these sapphires were classified as alkali feldspar, zircon, ferrocolumbite, pyrochlore, and iron oxides. Mineral chemical characteristics of these inclusions appearred to have evolved from alkaline felsic suite. Oxide mineral inclusions occurred in sapphire included hercynite, wüstite, and ilmenite. Ilmenite ranged in composition between Il49-54He34-40Mt7-10 and Il24-30He36-38Mt35-40 falling in ilmenite-hematite series. Wüstite with nonstoichiometry, (Fe2+0.3-0.9)(Ti3+<0.179Al3+≤0.6Cr3+<0.1 Fe3+≤0.46)£≤0.23O, was usually associated with hercynite inclusion clearly indicating cogenetic sapphire formation. Wüstite and sapphire appeared to have formed from the breakdown reaction of hercynite (hercynite = sapphire+wüstite). Titanohematite series and titanomagnetite series might have crystallized during iron-titanium reequilibration via subsolidus exsolution. U-Pb geochronology of zircon inclusion in these sapphires yielded between 35.5 ± 1.6 Ma (~35 Ma) and 14.73 ± 0.29 Ma (~15 Ma) for Krong Nang sapphire, 5.94 ± 0.13 Ma (~6 Ma) for Binh Thuan and Dak Nong sapphire, and 5.491 ± 0.077 Ma (~5.5 Ma) for Di Linh sapphire. These age constraints relate to the main Cenozoic basaltic eruptions in this region. Crystallization temperature of sapphire formation was estimated at about 561- 7810C using Ti-in-zircon thermometry.
Synthesis Of 1,2-Naphthoquinone Derivatives As Α-Glucosidase Inhibitors, Trang Pham Thi
Synthesis Of 1,2-Naphthoquinone Derivatives As Α-Glucosidase Inhibitors, Trang Pham Thi
Chulalongkorn University Theses and Dissertations (Chula ETD)
For a couple of decades the bioactivity of quinone has been considered as privileged structure-based drug design. In this research, 4-phenylamino, 4-alkylamino, 4-alkylphenylamino, 4-phenoxy and other derivatives of 1,2-naphthoquinone were synthesized, evaluated for their anti α-glucosidase activity and elucidated for their structure-activity relationship. The results indicated that multiple factors affecting to the α-glucosidase inhibition included π-π interaction, hydrophobic interaction and hydrogen bonding with the enzyme. In general, the main factor affecting the activity was the more favorable 1,2-dione production. The presence of electron withdrawing substituents on the phenyl ring and heteroatom linker bound to the quinone skeleton increased the activity. …
Sustainability Assessment Of Power Production By Chemical Looping Combustion, Watchara Uraisakul
Sustainability Assessment Of Power Production By Chemical Looping Combustion, Watchara Uraisakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigated the chemical looping combustion (CLC) process improvement for power production from energy management, system hydrodynamics, and sustainability perspectives. In the first part, the 3k factorial design was used for systematically investigating the operating variables that affect the thermal efficiency of the CLC combined with the humid air gas turbine (HAT) cycle. A set of operating variables, A) pressure of the air reactor, B) air compressor stages number, C) air compression methods, and D) air flow rate, were explored. The result showed that the highest thermal efficiency was at 55.87 % when operated at (A) 15 atm, (B) …
Intermodulation Distortions From A Chain Of Coupled Nonlinear Oscillators Near A Hopf Bifurcation, Yanathip Thipmaungprom
Intermodulation Distortions From A Chain Of Coupled Nonlinear Oscillators Near A Hopf Bifurcation, Yanathip Thipmaungprom
Chulalongkorn University Theses and Dissertations (Chula ETD)
The inner ear can produce sounds whose frequencies correspond to linear combinations of the stimulus frequencies, f1 and f2. These sounds, called Distortion Product Otoacoustic Emissions (DPOAEs), can be measured by inserting a microphone into the ear canal. In human, the intensity level of DPOAEs at frequency 2f1-f2 varies significantly with a stimulus frequency and can exhibit a quasi-periodic pattern, a feature termed a DPOAE fine structure. This distinctive characteristic has been generally accepted as a consequence of the interference between two DPOAE signals produced by two spatially separated groups of sensory hair cells, whose characteristic frequencies correspond to the …
Convergence Of Trinomial Formula For Call Option Prices, Yuttana Ratibenyakool
Convergence Of Trinomial Formula For Call Option Prices, Yuttana Ratibenyakool
Chulalongkorn University Theses and Dissertations (Chula ETD)
The binomial formula given by Cox, Ross and Rubinstein (1979) is a tool for valuating the call option price. It is well known that the price from binomial formula converges to the price from Black-Scholes formula which was given by Black, Scholes and Merton (1973) as the number of periods (n) converges to infinity. In 1988, Boyle introduced the trinomial formula which is another tool for calculating call option price. He considered the trinomial formula in the case that the rising rate of a stock price is u = e λσ√T n and the falling rate of the stock price …
Environmental Impacts And Hazardous Characteristics Of Led Lamps Waste, Delpavita Koralege Lakshani Diluka Gunawardhaa
Environmental Impacts And Hazardous Characteristics Of Led Lamps Waste, Delpavita Koralege Lakshani Diluka Gunawardhaa
Chulalongkorn University Theses and Dissertations (Chula ETD)
LED lighting technology has strongly taken the Thai lighting market due to the high consumption in residential, industrial and commercial sectors so the sustainability of LED lamps chain is considered as a critical factor for Thai lighting market. Additionally LED lamps waste consist of toxic metals hence improper landfilling has high potential to create negative environment and human health impact due to toxic metals contamination to environment. Therefore, this study focused on (1) quantifying environmental impact due to consumption behaviors among industrial lighting consumers and (2) hazard characterization and toxicity estimation of improper landfilling of LED lamps waste. Environmental impact …
Perspectives And Challenges Of Green Hotel In Thailand, Pornwajee Sangmanee
Perspectives And Challenges Of Green Hotel In Thailand, Pornwajee Sangmanee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The hotel business is intense resource consumption such as water, energy, and non-durable products to delight customers, leading to environmental problems. With this regard, the transformation of the green hotel and environmental saving programs can dwindle the hotel property's adverse impacts. The purposes of this paper are 1) to study the perception of hotel practitioners and stakeholders toward the critical challenges of green hotel transformation and 2) to propose the recommendations for green hotel operations and certification scheme in Thailand. The study employed mixed methods to collect the data. The in-depth interviews were along with field observation; the interviews data …
City-Wide Greenhouse Gas Mitigation Options To Support Global Climate Goals: Case Studies Of Bangkok, Chiang Mai, And Rayong, Thailand, Sittisak Sugsaisakon
City-Wide Greenhouse Gas Mitigation Options To Support Global Climate Goals: Case Studies Of Bangkok, Chiang Mai, And Rayong, Thailand, Sittisak Sugsaisakon
Chulalongkorn University Theses and Dissertations (Chula ETD)
The action of city on climate mitigation becomes a crucial role. The aims of this study were to quantify greenhouse gases (GHGs) emission, identify feasibility of mitigation options in selected provinces, and to evaluate the performance of local capacity to support Thailand's Nationally Determined Contributed (NDC) and 1.5oC limit pathway. Three provinces, including Bangkok, Chiang Mai and Rayong of Thailand were selected as case studies. The results revealed that stationary energy was the greatest contribution to the city's GHGs emissions in all case studies. Transportation was the second largest emitter in Bangkok and Chiang Mai, whereas IPPU was the second …
Sustainable Business Development Through Sufficiency Economy Practice : A Case Study Of Thai Listed Companies, Veerawin Korphaibool
Sustainable Business Development Through Sufficiency Economy Practice : A Case Study Of Thai Listed Companies, Veerawin Korphaibool
Chulalongkorn University Theses and Dissertations (Chula ETD)
The purpose of the research is to determine the sufficiency economy philosophy (SEP) performance through annual and sustainable development reports and simplify the outcomes by representing through a scoring system. Each of the SEP elements was aligned with each GRI sub-topic to generate a SEP scoring system. Then, the results from the scoring system were verified by testing the relationship between SEP performance and firm-specific risk of 34 Thai listed companies from 2013 to 2018 via panel data analysis. The global reporting initiative (GRI) standards were used as the fundamental scoring system as it's widely used and accepted in academic …
ผลของเอทิลีน-ออกทีนโคพอลิเมอร์และโวลลาสโทไนต์ต่อสมบัติของไนลอน 6, บุษยา วิลาวรรณ
ผลของเอทิลีน-ออกทีนโคพอลิเมอร์และโวลลาสโทไนต์ต่อสมบัติของไนลอน 6, บุษยา วิลาวรรณ
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้ พอลิเมอร์ผสมของไนลอน 6 กับเอทิลีน-ออกทีนโคพอลิเมอร์และเอทิลีน-ออกทีนโค พอลิเมอร์กราฟต์มาเลอิกแอนไฮไดรด์ ได้ถูกเตรียมด้วยกระบวนการผสมแบบหลอมเหลวโดยใช้เครื่องอัดรีดแบบสกรูคู่และขึ้นรูปชิ้นทดสอบด้วยเครื่องฉีดแบบ เพื่อศึกษาเปรียบเทียบสมบัติทางกายภาพ สมบัติเชิงกล สมบัติทางความร้อน และสัณฐานวิทยา พบว่าความทนแรงกระแทกของพอลิเมอร์ผสมไนลอน 6/เอทิลีน-ออกทีน โคพอลิเมอร์ทุกอัตราส่วนมีค่าต่ำกว่าไนลอน 6 ล้วน ทั้งที่อุณหภูมิ 23 องศาเซลเซียส และ -30 องศาเซลเซียส และมีค่าลดลงเมื่อปริมาณเอทิลีน-ออกทีนโคพอลิเมอร์เพิ่มขึ้น เนื่องจากความไม่เข้ากันของพอลิเมอร์ผสม ในขณะที่พอลิเมอร์ผสมไนลอน 6/เอทิลีน-ออกทีนโคพอลิเมอร์กราฟต์มาเลอิกแอนไฮไดรด์ทุกอัตราส่วนมีค่าความทนแรงกระแทกสูงกว่าไนลอน 6 และเพิ่มขึ้นตามปริมาณของเอทิลีน-ออกทีนโคพอลิเมอร์กราฟต์มาเลอิกแอนไฮไดรด์ เนื่องจากการเกิดอันตรกิริยาที่ดีของพันธะไฮโดรเจนระหว่างหมู่อะมิโนกับหมู่แอนไฮไดรด์ในเมทริกซ์ของไนลอน 6 สอดคล้องกับภาพที่ได้จากกล้องจุลทรรศน์อิเล็กตรอนแบบส่องกราด นอกจากนี้ยังพบว่าพอลิเมอร์ผสมทุกอัตราส่วนแสดงอัตราการหลอมไหล, ความถ่วงจำเพาะ, สมบัติความทนแรงดึง, สมบัติความทนแรงดัดโค้ง, ความแข็งแบบร็อคเวลล์, อุณหภูมิอ่อนตัวด้วยความร้อน, ร้อยละความเป็นผลึก, มอดุลัสสะสม และความต้านทานการหดตัวในแม่พิมพ์มีค่าลดลง เนื่องจากพฤติกรรมของความเป็นอิลาสโตเมอร์ของเอทิลีน-ออกทีนโค พอลิเมอร์ในพอลิเมอร์ผสม และจากสมบัติเชิงกลที่เหมาะสมจึงเลือกอัตราส่วน 85/15 (ร้อยละโดยน้ำหนัก) ของไนลอน 6/เอทิลีน-ออกทีนโคพอลิเมอร์กราฟต์มาเลอิกแอนไฮไดรด์สำหรับเตรียมคอมพอสิตกับโวลลาสโทไนต์ ที่ 10, 20 และ 30 ส่วนต่อเรซิน 100 ส่วน ผลการวิจัยพบว่าความถ่วงจำเพาะ, ยังส์มอดุลัส, มอดุลัสดัดโค้ง, อุณหภูมิอ่อนตัวด้วยความร้อน, มอดุลัสสะสม, ความต้านทานการหดตัวในแม่พิมพ์และความต้านทานการหลอมหยดเพิ่มขึ้น ในขณะที่ความทนแรงกระแทกที่ 23 องศาเซลเซียส และ -30 องศาเซลเซียส, ความทนแรงดึงและการยืดตัว ณ จุดขาด มีค่าลดลงเนื่องจากการเกิดอันตรกิริยาระหว่างโวลลาสโทไนต์และเมทริกซ์ต่ำ
Predicting Football Match Result Using Fusion-Based Classification Model, Chananyu Pipatchatchawal
Predicting Football Match Result Using Fusion-Based Classification Model, Chananyu Pipatchatchawal
Chulalongkorn University Theses and Dissertations (Chula ETD)
Over the last decades, various football experts and researchers around the world seek to forecast football match result. Although there are multiple types of prediction models constructed for this purpose, most of them still depends on integrating in-game statistical numbers, such as number of successful passes in one game. This kind of information has huge positive impact on predicting outcome but is not desired as it requires the match to finish first. Thus, this thesis aims to propose more accurate models, which are not relied on in-game numbers. Two forms of fusion-based classification models are proposed in this study, including …
Tuning Of Metal Ion Selectivity By Varying Number Of Coordinating Atoms In Quinoline-Derived Fluorescent Sensors, Jutawat Hojitsiriyanont
Tuning Of Metal Ion Selectivity By Varying Number Of Coordinating Atoms In Quinoline-Derived Fluorescent Sensors, Jutawat Hojitsiriyanont
Chulalongkorn University Theses and Dissertations (Chula ETD)
Both Cd2+ and Zn2+ are metal ions in group 12 elements with very different toxicities but similar binding properties to most organic and biological ligands. In this work, a series of quinoline derivatives were synthesized and studied with an aim for Cd2+ selective turn-on fluorescent sensors. The structures of the compounds were designed to systematically evaluate the effects of amino protons, number of N-coordinating atoms, quinoline/picoline moieties and substituents on the sensing properties. The association constants of all synthesized ligands were studied by UV-vis absorption titration in aqueous solution. The results revealed that the ligands having 6- and 4- donor …
Direct Synthesys Of Lpg From Co2 By Using Czza And Hy Zeolite Hybrid Catalyst, Jaru Natakaranakul
Direct Synthesys Of Lpg From Co2 By Using Czza And Hy Zeolite Hybrid Catalyst, Jaru Natakaranakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
CO2 conversion to lower hydrocarbons (HCs) is a high-potential method that can significantly reduce and manage this greenhouse gas in the long term. Liquefied petroleum gas (LPG) is widely utilized in transportation. Furthermore, biomass appears to be more attractive for decreasing CO2 emissions through conversion to liquid transportation fuels, as it is a renewable and sustainable energy source. The objectives of this work were to examine the direct synthesis of LPG from CO2 hydrogenation using a mixed metal catalyst composed of copper, zinc oxide, zirconium, and alumina (CZZA), and an HY zeolite as a hybrid catalyst. The study tested four …
Definable Modules Over Definable Rings Without Zero Divisors In O-Minimal Structures, Jaruwat Rodbanjong
Definable Modules Over Definable Rings Without Zero Divisors In O-Minimal Structures, Jaruwat Rodbanjong
Chulalongkorn University Theses and Dissertations (Chula ETD)
In an o-minimal structure, every definable group admits a definable group manifold. Moreover, one can also show an analogue of this statement for definable rings. In this work, we prove that every definable module over definable ring without zero divisors admits a definable module manifold. In addition, we also give the classification of definable modules over definable rings without zero divisors in o-minimal structures
Holographic Solutions From N=6, D=4 Gauged Supergravity, Jakkapat Seeyangnok
Holographic Solutions From N=6, D=4 Gauged Supergravity, Jakkapat Seeyangnok
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this thesis, we study holographic solutions of four-dimensional N = 6 gauged supergravity with SO(6) gauge group. The theory admits a unique N = 6 supersymmetric AdS4 vacuum dual to a three-dimensional N = 6 SCFT and gives us a number of supersymmetric domain walls interpolating between this AdS4 vacuum and singular geometries in IR with SO(2) × SO(4), U(3), SO(2) × SO(2) × SO(2), and SO(3) symmetries. These solutions describe RG flows from N = 6 SCFT in UV to non-conformal field theories driven by mass deformations. In particular, the solution with SO(2)×SO(4) symmetry coincides with the known …
Development Of Cellulose As Substrates For Adsorbents And Sensors, Jadetapong Klahan
Development Of Cellulose As Substrates For Adsorbents And Sensors, Jadetapong Klahan
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis deals with two parts of development of novel sensors based on cellulose substrate platform. The first part is the development of fluorescence sensors and adsorbents for metal ions using bacterial cellulose as the platform. The second part is the development of colorimetric sensors for smartphone detection of oil marker using filter paper as the platform. In the first part, bacterial cellulose (BC) has several advantageous properties over plant cellulose such as high purity, high surface area, high porosity, and high water-holding capacity due to its three-dimensional network of nanofibrils structure, that make BC appealing for applications related to …
Regenerated Amorphous Cellulose From Pineapple Leaf Fibers Via Sulfuric Acid Treatment, Gisma Coraima Asmarani
Regenerated Amorphous Cellulose From Pineapple Leaf Fibers Via Sulfuric Acid Treatment, Gisma Coraima Asmarani
Chulalongkorn University Theses and Dissertations (Chula ETD)
Pineapple leaf fiber (PALF) is an agricultural residue available abundantly in Thailand as a renewable resource with high cellulose content. In this research, a simple process using sulfuric acid (H2SO4) treatment has been developed to produce three types of cellulosic products from PALF, which are regenerated amorphous (RAC), microcrystalline (MCC), and nanocrystalline (NCC) cellulose. H2SO4 acid treatment has been done in 25% and 50% (v/v) H2SO4 under three different temperatures (-20, 30, and 50 ºC). In 25% (v/v) H2SO4, various MCC lengths (about 29.57 ± 9.99 to 106.40 ± 61.10 μm) were produced from different temperatures. Different temperatures in this …
Electrocoagulation In Two Phase Separation For Manipulation Of Volatile Compound Profiles In Perfumes, Isaya Thaveesangsakulthai
Electrocoagulation In Two Phase Separation For Manipulation Of Volatile Compound Profiles In Perfumes, Isaya Thaveesangsakulthai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Electrocoagulation (EC) approach employing two aluminium electrodes and a two phase medium of aqueous solution of NaCl and hexane (2-phase-EC) was developed. The approach enabled electrochemical treatment of odor active compounds in perfume extract. The samples before and after 2-phase-EC at cathode, anode and between the two electrodes left for equilibrium after the treatment were analyzed by using solid phase micro extraction (SPME) and gas chromatography hyphenated with mass spectrometry (GC-MS). This allowed identification of volatile compounds in each sample based on comparison with MS and retention index database. After the treatment, the perfume smells were fresher, sweeter and more …
Detecting Faces With Covid Protection Masks From Images Shot In Public Places Using Neural Networks, Hangkai Wang
Detecting Faces With Covid Protection Masks From Images Shot In Public Places Using Neural Networks, Hangkai Wang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Since 2019, Covid-19 has become a common problem affecting all mankind. The disease has successfully spread all over the world. Wearing a mask can practically protect the infection. Thus, detecting people wearing and not wearing masks in public is essential. However, there is still some room to improve detection accuracy of the present methods. In this paper, the transfer learning model and FR-TSVM model are used to study the latest data of pneumonia epidemic situation in Covid-19. First, a data set of 11600 facial images wearing masks and not wearing masks in public was collected for training, testing, and validation. …
Cryptosystem For Textual Message By Using Malleable Neural Network With Secret Dimensions, Hangyi Wang
Cryptosystem For Textual Message By Using Malleable Neural Network With Secret Dimensions, Hangyi Wang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Most of the current cryptography is based on modulo computing with predefined public and private keys. The robustness of this approach is controlled by the size of the prime divider. The encryption and decryption processes of this modulo computing are rather fast and rather robust to any attack. However, it is still possible to crack the encrypted message by using meta-heuristic algorithm, very high performance parallel machines, and also quantum computing concept. This thesis takes another approach in order to enhance the robustness of encrypted messages by deploying the structure of a feedforward neural network with augmented secret dimensions concurred …