Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2019

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 12871 - 12900 of 13031

Full-Text Articles in Physical Sciences and Mathematics

Development Of Biosensor Using Pyrrolidinyl Pna For Screening Of Hepatitis C Virus Dna, Narathorn Nisab Jan 2019

Development Of Biosensor Using Pyrrolidinyl Pna For Screening Of Hepatitis C Virus Dna, Narathorn Nisab

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, a new paper-based analytical device (PAD) that relied on fluorescence measurement was developed for label-free detection of hepatitis C virus (HCV) DNA. Pyrrolidinyl peptide nucleic acid (acpcPNA) was covalently modified onto the patterned cellulose paper to act as a specific probe for capturing the HCV DNA target according to Watson−Crick base-paring rules. The single-stranded (ssDNA)-specific dye which can be electrostatically attached to the surface-bound DNA was employed as the signaling element for the fluorescence-based detection via a smartphone gadget and an iOS application. To acquire the optimal sensitivity, several experimental parameters, namely acpcPNA probe concentration, hybridization time, …


Preparation Of Calcium Citrate Based Vitamin B₁₂/Cisplatin Nanocomposite As Novel Targeted Drug Carrier, Natchanon Rimsueb Jan 2019

Preparation Of Calcium Citrate Based Vitamin B₁₂/Cisplatin Nanocomposite As Novel Targeted Drug Carrier, Natchanon Rimsueb

Chulalongkorn University Theses and Dissertations (Chula ETD)

The synthesis of calcium citrate-cisplatin composite nanoparticles (CaCit@CDDP) was prepared via simple chemical co-precipitation method. Carboxyl group on the surface of calcium citrate nanoparticle was successfully modified with vitamin B12 (B12). The spherical nanoparticles were observed by Scanning Electron Microscope. The obtained size was 553.0±65.0 nm. The percentage of CDDP and B12 in the nanoparticles were analysed by Thermogravimetric Analysis and Inductively Coupled Plasma Optical Emission Spectroscopy. The interior of the nanoparticles was studied by Raman spectroscopy. Moreover, the Prestoblue viability assay showed that CaCit@CDDP-B12 significantly decreased 60% of cell viability of A549 cancer cell line in comparison to the …


Chemical Constituents And Antibacterial Activity Of Rhizomes From Globba Schomburgkii Hook.F., Naruemon Suekaew Jan 2019

Chemical Constituents And Antibacterial Activity Of Rhizomes From Globba Schomburgkii Hook.F., Naruemon Suekaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

Globba schomburgkii Hook.f. rhizomes were extracted with dichloromethane and fractionated using column chromatography to obtain 10 fractions (FA-FJ). The most active fractions, FE and FG, were further fractionated to give seven and thirteen sub-fractions, respectively. The fractions and sub-fractions were tested for antibacterial activity using 96-well plate microdilution method. The antibacterial activity of several sub-fractions (such as FE.B, FE.C, FE.D, FG.D, FG.G, and FG.H) were higher than that of the crude extract. Chemical compositions of all fractions and sub-fractions were analyzed by gas chromatography hyphenated with mass spectrometry (GC-MS), revealing 167 compounds identified according to match between the experimental MS …


Development Of Thin-Layer Chromatography For Selective Analysis Of Volatile Compounds Using Gas Chromatography Mass Spectrometry, Nattapat Suchatanugal Jan 2019

Development Of Thin-Layer Chromatography For Selective Analysis Of Volatile Compounds Using Gas Chromatography Mass Spectrometry, Nattapat Suchatanugal

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, simple and selective solid phase extraction approach for a range of volatile compounds in perfume was developed prior to analysis with headspace solid phase micro extraction (HS-SPME) and gas chromatography hyphenated with mass spectrometry (GC-MS). The technique relies on use of thin layer chromatography (TLC) for separation of compound along the silica gel plate followed by selective cuts of the regions of interest, desorption, HS-SPME and GC-MS analysis. The TLC separation of standard compounds using hexane and ethyl acetate (6:1 volume ratio) as the mobile phase was initially performed. The compounds was then desorbed from the TLC …


Structure And Hydration Property Of Low Molecular Weight Hyaluronic Acid By Molecular Dynamics Simulations, Panyakorn Taweechat Jan 2019

Structure And Hydration Property Of Low Molecular Weight Hyaluronic Acid By Molecular Dynamics Simulations, Panyakorn Taweechat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Hyaluronic acid (HA) is a biopolymer of disaccharide with two alternate glycosidic bonds, β(1,3) and β(1,4). It has a wide-range of applications in medicine, nutrition and cosmetics. A molecular dynamics (MD) study in aqueous condition presented here unveiled conformational variability in association with the flexibility of the glycosidic linkers, which depends on the number of disaccharide units. HA chain maintains a rigid rod-like conformation with short chain lengths i.e. with 1 to 10 disaccharide units. Crossover from a rod-like to a random-coil conformation is observed with increasing the chain length i.e. with 20-50 disaccharide units. MD and DFT calculations demonstrated …


Flexible Sers Substrate Fabricated From Gold Nanostar, Piboonwan Insiti Jan 2019

Flexible Sers Substrate Fabricated From Gold Nanostar, Piboonwan Insiti

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, a one-pot protocol for the fabrication of surface-enhanced Raman scattering (SERS) substrate has been developed. It consists of quasi-spherical gold nanoparticles (AuQNPs) uniformly which is deposited on a disk paper substrate (5-mm in diameter). The disk of filter paper surface was coated by bacterial cellulose nanocrystal (BCNC). The BCNC smoothed the surface by forming thin nanopaper film upon drying while filling the gap between fibers. AuQNPs was directly synthesized on the surface of BCNC film via seed-growth method. The BCNC film with abundant hydroxyl groups became anchor points for AuNPs which help to create uniform distribution of …


Detection Of Nitrite By Thread-Based And Paper-Based Devices By Modified Griess Reagent, Pitcha Singhaphan Jan 2019

Detection Of Nitrite By Thread-Based And Paper-Based Devices By Modified Griess Reagent, Pitcha Singhaphan

Chulalongkorn University Theses and Dissertations (Chula ETD)

New thread-based and paper-based devices for the determination of nitrite ions based on modified Griess reagent were developed. The surface of the materials was chemically modified with p-aminobenzoyl moiety and chromotropic acid was used as a coupling reagent. The functionalization of the materials was confirmed by Raman spectroscopy. By using the thread-based device, the detection of nitrite was achieved by measuring the color band length. The optimum concentration of chromotropic acid was 5 mM in 0.10 M sulfuric acid mixed with 0.2 M citric acid. The working range was from 50 to 1,000 µM with a sample volume of 15 …


Detection Of Cyanide Ions Using Chemosensing Ensembles Under Indicator Displacement Assays, Ratanakorn Teerasarunyanon Jan 2019

Detection Of Cyanide Ions Using Chemosensing Ensembles Under Indicator Displacement Assays, Ratanakorn Teerasarunyanon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Anion recognition is an attractive area of research in recent decades as anions play an important role in a wide range of chemical, biological, and environmental processes. This dissertation reports three projects dedicated to anion recognition with applications in fluoride and cyanide sensing. The first project of the dissertation describes the chemistry of two novel anthracene derivatives bearing one and two dimesitylboryl substituents (compounds 1 and 2, respectively) for the complexation of anions. All investigations provide insights into the electronic structure and effect of fluoride and cyanide binding. The results demonstrate that these boranes have a high affinity for fluoride …


Development Of Paper-Based Colorimetric Sensor For Determination Of Human Papillomavirus Dna, Sarida Naorungroj Jan 2019

Development Of Paper-Based Colorimetric Sensor For Determination Of Human Papillomavirus Dna, Sarida Naorungroj

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, a paper-based analytical device (PAD) based on colorimetric assay using pyrrolidinyl peptide nucleic acid (acpcPNA) probe was developed as a sensor for the detection of Human papillomavirus (HPV) DNA. Dextrin-stabilized gold nanoparticles (d-AuNPs) was employed as a colorimetric reagent. The aggregation of d-AuNPs can be induced by positively charged acpcPNA generating a distinctive color change. After the hybridization of acpcPNA and DNA target, the residual acpcPNA probe can cause different degrees of the d-AuNPs aggregation, resulting in the detectable color change. The different color change before and after the introduction of the DNA target as a function …


Optimization Of Enantiomeric Separation By Gas Chromatography Using Beta-Cyclodextrin Derivatives As Stationary Phases, Suchada Muangsri Jan 2019

Optimization Of Enantiomeric Separation By Gas Chromatography Using Beta-Cyclodextrin Derivatives As Stationary Phases, Suchada Muangsri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Enantiomeric separations of seventy-two underivatized chiral alcohols and forty-three trifluoroacetyl derivatives of chiral amines of various structures were investigated by gas chromatography using two types of cyclodextrin-based chiral stationary phases: heptakis(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-beta-CD (or BSiAc) and heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl)-beta-CD (or BSiMe). Each compound was analyzed by temperature program and the optimum isothermal condition for each compound was also determined. It was found that resolution and elution temperature obtained from a temperature program run could be used as a guideline for quickly determining the optimum isothermal condition for enantiomeric separation. For a 15-meter long capillary column, if a resolution less than 1.0 was obtained, a …


Development Of Fluorinated Rhodacyanine Analogues For Anti-Leishmaniasis, Thitiya Lasing Jan 2019

Development Of Fluorinated Rhodacyanine Analogues For Anti-Leishmaniasis, Thitiya Lasing

Chulalongkorn University Theses and Dissertations (Chula ETD)

Recently, fluorinated rhodacyanine has been disclosed as a highly effective agent against Leishmania donovani; it was shown that replacement of hydrogen with a fluorine atom on a benzothiazole unit significantly enhanced the anti-leishmanial activity. However, the role of the fluorine substituent in this analogue has not yet been clarified and mechanism of actions remains unclear. In this research, fifteen novel and three known fluorine-containing rhodacyanine analogues (10c, and 11a-11q) were synthesized and tested the anti-leishmanial activity against promastigote and axenic amastigote stages of L. martiniquensis and L. orientalis, the indigenous Leishmania species of Thailand. The SAR knowledge of this series …


Synthesis Of Coumarins As Carbonic Anhydrase Ii And Α-Glucosidase Inhibitors, Truc Phan Thi Hong Jan 2019

Synthesis Of Coumarins As Carbonic Anhydrase Ii And Α-Glucosidase Inhibitors, Truc Phan Thi Hong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Coumarins have been occupied an important position in medicinal chemistry. In this research, umbelliferone derivatives were evaluated for inhibitory activity of two enzymes, namely carbonic anhydrase II (CA II) and α-glucosidase. First, ether, brominated ether and ester derivatives of umbelliferone were synthesized, characterized and tested for CA II inhibitory activity. However, the inhibition data could not be used to make the exact conclusion about structure-activity relationship owing to their unrepeatable results. For the second part, thirty-four derivatives of umbelliferone (ether, brominated ether, ester, sulfonamide and sulfonate derivatives) were synthesized and explored for anti-α-glucosidase activity. It was disclosed that anti-α-glucosidase activity …


Thai Spelling Correction And Word Normalization On Social Text Using A Two-Stage Pipeline With Neural Contextual Attention, Anuruth Lertpiya Jan 2019

Thai Spelling Correction And Word Normalization On Social Text Using A Two-Stage Pipeline With Neural Contextual Attention, Anuruth Lertpiya

Chulalongkorn University Theses and Dissertations (Chula ETD)

Text correction systems (e.g., spell checkers) have been used to improve the quality of computerized text by detecting and correcting errors. However, the task of performing spelling correction and word normalization (text correction) for Thai social media text has remained largely unexplored. In this thesis, we investigated how current text correction systems perform on correcting errors and word variances in Thai social texts and propose a method designed for this task. We have found that currently available Thai text correction systems are insufficiently robust for correcting spelling errors and word variances, while the text correctors designed for English grammatical error …


Quantum Comparator Circuit On Superconducting Quantum Computer, Naphan Benchasattabuse Jan 2019

Quantum Comparator Circuit On Superconducting Quantum Computer, Naphan Benchasattabuse

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we present an optimised quantum comparator circuit based on Cuccaro's ripple-carry quantum adder using relative phase techniques from Maslov's multiple control Toffoli optimisation. We extend the cost function from simply counting C-Not and Toffoli gate to Qiskit cost which defines arbitrary single qubit gate cost as unity and C-Not as the only two qubit gate cost as ten. We report the comparison result between our comparator circuit with previous comparator circuits from literature using optimal Toffoli implementation with Qiskit cost, C-Not count, and circuit depth. We also report our experiment of implementing a two-bit comparator on IBM …


A Peer-To-Peer Protocol For Prioritized Software Updates On Wireless Sensor Networks, Natchanon Nuntanirund Jan 2019

A Peer-To-Peer Protocol For Prioritized Software Updates On Wireless Sensor Networks, Natchanon Nuntanirund

Chulalongkorn University Theses and Dissertations (Chula ETD)

Software updating is essential for devices in wireless sensor networks for adding new features, improving performance, or patching vulnerabilities. But since some deployed devices are unable to be accessed directly, data dissemination protocol is used for distributing the update to those devices. However, each software updating may have different priority, for instance, an update that adds an optional feature does not have to be applied as fast as an update that patches severe vulnerabilities. This research presents a reliable data dissemination protocol which is configurable for energy-speed trade-off deriving some concepts from BitTorrent such as Handshaking, Segmented File Transfer, and …


Semantic Segmentation On Remotely Sensed Images Using Deep Convolutional Encoder-Decoder Neural Network, Teerapong Panboonyuen Jan 2019

Semantic Segmentation On Remotely Sensed Images Using Deep Convolutional Encoder-Decoder Neural Network, Teerapong Panboonyuen

Chulalongkorn University Theses and Dissertations (Chula ETD)

One of the fundamental tasks in remote sensing is the semantic segmentation of the aerial and satellite images. It plays a vital role in applications, such as agriculture planning, map updates, route optimization, and navigation. The state-of-the-art model is the Deep Convolutional Encoder-Decoder (DCED). However, the accuracy is still limited since the architecture is not designed for recovering low-level features, e.g., river, low vegetation on remotely sensed images, and the training data in this domain are deficient. In this dissertation, we aim to propose the semantic segmentation architecture in five aspects, designed explicitly for the remotely sensed field. First, we …


Ocean Current Prediction In The Gulf Of Thailand Using Spatio-Temporal Deep Learning On High-Frequency Radar, Nathachai Thongniran Jan 2019

Ocean Current Prediction In The Gulf Of Thailand Using Spatio-Temporal Deep Learning On High-Frequency Radar, Nathachai Thongniran

Chulalongkorn University Theses and Dissertations (Chula ETD)

Ocean surface current prediction is a crucial task for a variety of marine activities, such as disaster monitoring, search and rescue operations, power forecasting, and etc. There are three traditional forecasting approaches: (i) numerical based approach, (ii) time series based approach and (iii) machine learning based approach. However, their prediction accuracy was limited as they did not cooperate with spatial and temporal effects together, including oceanic knowledge is also not considered. This paper introduces the ocean surface prediction model that accounts for spatial and temporal characteristics by a combination between CNN and GRU and also the incorporation of oceanic inputs …


Facial Features Detection System For Classifying Critical Situation Of Brain Surgery Postoperative Patients, Bhatarasiri Slakkham Jan 2019

Facial Features Detection System For Classifying Critical Situation Of Brain Surgery Postoperative Patients, Bhatarasiri Slakkham

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purpose of this research is to create a model for detecting a help signal from stroke patients after surgery. Through artificial intelligence technology by detecting via a patient's face image to help reducing workload and hospital’s expenses. The data is collected from the Stroke Unit, King Chulalongkorn Memorial Hospital at the intensive care unit (ICU). The total number of samples is 8 persons, all these 8 were screened by the doctor and completed the consent forms before data being collected. The method of data collection is performed by attaching 3 small cameras on three positions: the left, right and …


Automatic Model Identification For Time Series Analysis Using Deep Learning, Paisit Khanarsa Jan 2019

Automatic Model Identification For Time Series Analysis Using Deep Learning, Paisit Khanarsa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Most time series data can be characterized by a linear process via the autoregressive integrated moving average model requiring a three-component vector which are the autoregressive, differencing, and moving average orders before fitting coefficients. A model identification which determines those orders is analyzed via the partial autocorrelation function to identify the autoregressive order, the autocorrelation function to identify the moving average order and an extended sample autocorrelation function to identify both orders which is a challenging problem for statisticians. Accordingly, the auto-ARIMA model was proposed to automatically vary those orders and estimates their corresponding coefficients. This thesis proposes three architectures …


Self-Balancing Recursive Partitioning Algorithm For Classification Problems, Artit Sagoolmuang Jan 2019

Self-Balancing Recursive Partitioning Algorithm For Classification Problems, Artit Sagoolmuang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Creating an effective classification model has been played an important role in knowledge discovery in a database methodology for the past several years. However, there is a critical issue that significantly affects the classification performance appearing in many real-world situations, which is called a class imbalanced problem. In this dissertation, a classification model built based on the recursive partitioning algorithm is improved under the concept of modified entropy components for handling a classification problem regardless of the class imbalanced situation. Three methodologies are introduced for achieving different purposes. The first methodology is presented to classify a binary-class imbalanced dataset dealing …


Solving System Of Linear Integro-Differential Equations By Finite Integration Method With Shifted Chebyshev Polynomials, Matinee Juytai Jan 2019

Solving System Of Linear Integro-Differential Equations By Finite Integration Method With Shifted Chebyshev Polynomials, Matinee Juytai

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we modify the finite integration method by using the shifted Chebyshev polynomial (FIM-SCP). The major tool of our FIM-SCP is the shifted Chebyshev integration matrix. It is constructed in order to be a matrix representation for integrating over interpolated points which are generated by the zeros of shifted Chebyshev polynomial of a certain degree. The efficiently numerical algorithms are then created by the modified FIM-SCP for seeking approximate solutions of a system of stiff linear ordinary differential equations, a system of linear Volterra integro-differential equations, and a system of linear Fredholm integro-differential equations under some given boundary …


Chemometric Method To Enhance Sensitivity And Selectivity For Surface Enhanced Raman Scattering Technique, Nontawat Sricharoen Jan 2019

Chemometric Method To Enhance Sensitivity And Selectivity For Surface Enhanced Raman Scattering Technique, Nontawat Sricharoen

Chulalongkorn University Theses and Dissertations (Chula ETD)

The multivariate curve resolution-alternative least square (MCR-ALS) algorithm was modified with sample insertion constraint. This developed method was proposedly used to deconvolute the overlapping signals in Surface enhance Raman attering (SERS) measurement. The developed method was elucidated with the spectral data simulated by using Gaussian distribution function to generate two independent peaks which correspond to capping agent and analyte, respectively. The spectrum of the two peaks was generated with different overlapping levels (RS = 0 – 1.50) and concentration ratio of analyte and capping agent concentration at 0.01 – 1.00. In MCR-ALS with sample insertion constraint, the number of capping …


Determination Of Perchlorate And Thiocyanate Ions By Ion-Selective Membrane And Bulk Optode Techniques Using Experimental Design Approach, Supacha Wirojsaengthong Jan 2019

Determination Of Perchlorate And Thiocyanate Ions By Ion-Selective Membrane And Bulk Optode Techniques Using Experimental Design Approach, Supacha Wirojsaengthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aimed to develop the detection method for perchlorate and thiocyanate in aqueous solutions using potentiometric and colorimetric techniques. The optimum conditions were designed by the central composite design (CCD) with response surface methodology (RSM). The potentiometric response of perchlorate‒selective electrode using di‒tripodal amine calix[4]arene copper(II) complex (L1-Cu) in PVC membrane was studied. The optimized pH, ion exchanger and ionophore concentrations were found at pH 8.0, 3.25 mmol/kg and 13.25 mmol/kg, respectively. The optimized condition performed a Nernstian slope of –58.02 mV/decade with R2=0.9994 in a working concentration range of 1.00×10‒6 – 1.00×10‒2 M, and the detection limit was …


Development Of Green Methods For Synthesis Of 2-Aminobenzoxazoles From Organosulfurs, Theeranon Tankam Jan 2019

Development Of Green Methods For Synthesis Of 2-Aminobenzoxazoles From Organosulfurs, Theeranon Tankam

Chulalongkorn University Theses and Dissertations (Chula ETD)

2-aminobenzoxazoles are an important motif in pharmaceutical and chemical industries, however, their preparations involve the use of toxic reagents and organic solvents. Therefore, greener methods for preparation of 2-aminobenzoxazoles are highly desired. In this work, we demonstrate two novel methodologies for synthesis of 2-aminobenzoxazoles in aqueous media. The first method involves the use of "on water" microwave reaction to perform the amination of 2-mercaptobenzoxazoles into 2-aminobenzoxazoles. Various 2-aminobenzoxazoles are synthesized under additive-free condition accelerating by microwave irradiation at 100 oC for 1 hour in moderate to good yields. This synthesis can be applied to prepare 2-aminobenzoxazole in gram scale quantity. …


Bioactive Compounds From Lichen Usnea Aciculifera Vain And Usnic Acid Conjugates, Truong Tuong Lam Jan 2019

Bioactive Compounds From Lichen Usnea Aciculifera Vain And Usnic Acid Conjugates, Truong Tuong Lam

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phytochemical investigation of lichen Usnea aciculifera Vain led to the isolation of nine new dimeric xanthones, usneaxanthones A-I (36–44), along with 36 known compounds (1–35, 45). The chemical structures of the isolated compounds were elucidated by a combination spectroscopic data (1D, 2D NMR, HRESIMS), ECD experiments, and single-crystal X-ray as well as comparison of their NMR data with those in the literature. The biological activities of isolated compounds were evaluated for antibacterial, anti-dengue and cytotoxic activites. The results revealed that depsides may have potential as lead compounds for the development of new antibacterial and anti-dengue agents. Futhermore, dimeric xanthones exhibited …


Semi-Supervised Deep Learning With Malignet For Bone Lesion Instance Segmentation Using Bone Scintigraphy, Terapap Apiparakoon Jan 2019

Semi-Supervised Deep Learning With Malignet For Bone Lesion Instance Segmentation Using Bone Scintigraphy, Terapap Apiparakoon

Chulalongkorn University Theses and Dissertations (Chula ETD)

One challenge in applying deep learning to medical imaging is the lack of labeled data. Although large amounts of clinical data are available, acquiring labeled image data is difficult, especially for bone scintigraphy (i.e., 2D bone imaging) images. Bone scintigraphy images are generally noisy, and ground-truth or gold standard information from surgical or pathological reports may not be available. We propose a novel neural network model that can segment abnormal hotspots and classify bone cancer metastases in the chest area in a semi-supervised manner. Our proposed model, called MaligNet, is an instance segmentation model that incorporates ladder networks to harness …


Gui Test Case Prioritization Using Social Network Analysis, Chawannut Maitrikul Jan 2019

Gui Test Case Prioritization Using Social Network Analysis, Chawannut Maitrikul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Graphical User Interfaces (GUIs) has become popular in today software products due to its user-friendly merit. However, GUI tests are costly and suffer explosive test cases. Moreover, software evolution causes the GUIs inevitably changed resulting in harder testing. Regression test has been widely used for GUIs software testing when software changes. It is considered to be the most expensive phase in the software testing process, though. Among several alternatives, the technique of test case prioritization would help identify the reduced set of test cases in the regression testing suite, still maintain the same criteria as the original number of test …


Heavy Metals In Hair And Nails Of Electronic Waste Dismantling Workers In Buriram, Thailand, Jaruwan Silachan Jan 2019

Heavy Metals In Hair And Nails Of Electronic Waste Dismantling Workers In Buriram, Thailand, Jaruwan Silachan

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to investigate and compare the concentration of eight heavy metals (As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn) in hair and nails of e-waste workers and non-e-waste workers. Hair and nails samples were collected from participants in Daeng Yai sub-district, Ban Mai Chaiyapot district, and Ban Pao sub-district, Puttatisong district, Buriram, Thailand from December 2018 to January 2019. All sampled were digested with nitric acid by microwave digester and the concentration of heavy metals was analyzed by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results showed that the concentration of As and Cd in both …


Blood Lead And Cadmium Levels Of E-Waste Dismantling Workers From Inhalation Exposure To Pm2.5 And Pm2.5-10, Buriram, Thailand, Thidarat Sirichai Jan 2019

Blood Lead And Cadmium Levels Of E-Waste Dismantling Workers From Inhalation Exposure To Pm2.5 And Pm2.5-10, Buriram, Thailand, Thidarat Sirichai

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aims to investigate blood lead and cadmium levels in associated with inhalation exposure of Pb and Cd in PM2.5 and PM2.5-10 of the e-waste dismantling workers and non-e-waste dismantling workers in Daeng Yai sub-district, Ban Mai Chaiyapot district, and Ban Pao sub-district, Puttatisong district, Buriram, Thailand, during May to August 2019. Blood samples were collected on the next day after the air sampling. Pb and Cd in blood and air samples were quantitatively analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The mean blood lead levels of e-waste workers from Daeng Yai sub-district, and Ban Pao sub-district, and …


Pointwise Dimension Of Archimedean Copulas, Noppawit Yanpaisan Jan 2019

Pointwise Dimension Of Archimedean Copulas, Noppawit Yanpaisan

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we introduce the pointwise dimension of a bivariate copula C at (u,v) in [0, 1]2 via its C-volume. This quantity gives a broader view of probability mass distribution than the support of a copula, the smallest closed set on which the whole mass lies. We would like to study some fundamental properties of pointwise dimension, including the equality to pointwise exponent whenever both of them exist. After that, we investigate the behavior of the pointwise dimension of copulas constructed by various methods. In the last part, we compute the pointwise dimension of Archimedean copulas, an important class …