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Articles 391 - 420 of 2268
Full-Text Articles in Physical Sciences and Mathematics
Newton Iterative Algorithm For Polynomial Modular Inversion Modulo Xn±1 For Some Patterns Of N, Samakorn Sripatthanakul
Newton Iterative Algorithm For Polynomial Modular Inversion Modulo Xn±1 For Some Patterns Of N, Samakorn Sripatthanakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis presents an algorithm for computing the modular inverse of a polynomial in a ring of polynomials over a finite field $\mathbb{F}_q$ with a characteristic $p$. Given a polynomial $f$ and a natural number $r$, by applying the idea of the Newton iteration algorithm, the fast division algorithm used to find the inverse of $f$ under modulo $x^{p^r}-1$, $x^{p^r}+1$, $x^{2p^r}-1$ and $x^n-1$ where $n=2^r d$ for some $r,d\in\mathbb{N}$, is established. The cost analysis for these cases show that the algorithm has the computational complexity of $\mathcal{O}(n \log n)$ which is more efficient than the Half-GCD algorithm in terms of …
Scheduling Of Pressing Process In Multi-Layer Printed Circuit Board Manufacturing Via Milp And Heuristic, Teeradech Laisupannawong
Scheduling Of Pressing Process In Multi-Layer Printed Circuit Board Manufacturing Via Milp And Heuristic, Teeradech Laisupannawong
Chulalongkorn University Theses and Dissertations (Chula ETD)
The pressing process aims to press the panel which is the stack of materials to form a multi-layer printed circuit board (PCB). This process is a part of multi-layer PCB fabrication and can be considered as a scheduling problem with the objective of minimizing the makespan. In this dissertation, two mixed-integer linear programming models (Models 1 and 2) and a three-phase-PCB-pressing heuristic (3P-PCB-PH) algorithm for scheduling the pressing process are presented. Model 2 is an improvement of Model 1 in terms of the model size and the dimensionality of some decision variables. Both models and the 3P-PCB-PH algorithm are used …
Special Types Of Tolerance And Control Solutions To System Of Interval Linear Equations, Warintorn Pongsumrankul
Special Types Of Tolerance And Control Solutions To System Of Interval Linear Equations, Warintorn Pongsumrankul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this thesis, we study a system of interval linear equations of the form Ax=b which includes an interval coefficient matrix and an interval right hand side vector. There are many types of solutions of this system which serve the different semantics in real-life situations such as tolerance and control solutions. We pay attention to the semantics that some boundaries of intervals are important. Moreover, we combine these semantics together with the semantics of tolerance and control solutions in order to present the new types of solutions to Ax=b, called special tolerance left, special tolerance right, special control left and …
Carbon Dioxide Hydrogenation To Methane Over Silica Supported Nickel Catalysts In A Differential Reactor And Kinetic Model Development, Angkana Khuenpetch
Carbon Dioxide Hydrogenation To Methane Over Silica Supported Nickel Catalysts In A Differential Reactor And Kinetic Model Development, Angkana Khuenpetch
Chulalongkorn University Theses and Dissertations (Chula ETD)
Development of a kinetic model for CO2 methanation over a commercial nickel catalyst was performed to consider pathways of CO2 conversion via Sabatier and RWGS reactions. H2/CO2 ratio in the feed gas composition was varied at the stoichiometry of the Sabatier reaction assuming a fictitious CO2 conversion of 0 to 0.7. Non-stochiometric gas feeding and the addition of product gases, i.e., methane and steam, were also considered to examine reaction orders and inhibition effects. The kinetic tests were carried out at 300–350 °C and 0.1–0.9 MPa. GHSV corresponded to 37,494 h-1. The stable activity was achieved by forcibly stressing the …
Synthesis And Catalytic Activity Of Layered Double Hydroxide And Metal Sulfide Nanoparticle Composites, Ajirawadee Suwanchan
Synthesis And Catalytic Activity Of Layered Double Hydroxide And Metal Sulfide Nanoparticle Composites, Ajirawadee Suwanchan
Chulalongkorn University Theses and Dissertations (Chula ETD)
Degradation of methylene blue dye was investigated over heterogenous catalytic process using layered double hydroxide and metal sulfide nanoparticle composites. CuCo2S4/NiFe LDH nanocomposites were synthesized using hydrothermal method, and the composites were characterized by SEM and XRD techniques. CuCo2S4 and NiFe LDH were formed with an average particle in the range of 350-450 nm and 2200-3500 nm, respectively. The composites were loaded at 1.8, 3.4, 5.2 and 9.9 wt% of CuCo2S4. CuCo2S4, NiFe LDH and CuCo2S4/NiFe LDH composites were tested at the same condition for methylene blue degradation. The 18CuCo2S4/NiFe LDH composites provided higher catalytic degradation of methylene blue compared …
Mesoporous Carbon/Silica Nanocomposites With Acid And Base Properties For Glucose Conversion Into Value Added Chemicals, Satit Yousatit
Mesoporous Carbon/Silica Nanocomposites With Acid And Base Properties For Glucose Conversion Into Value Added Chemicals, Satit Yousatit
Chulalongkorn University Theses and Dissertations (Chula ETD)
The purpose of this study is to prepare mesoporous carbon/silica (MCS) nanocomposites using natural rubber (NR) as a renewable carbon source. A series of mesoporous nanocomposites based on NR and hexagonal mesoporous silica (HMS), prepared via an in situ sol-gel process, were used as precursors, which were then converted into the MCS materials by carbonization. The sulfonic acid-functionalized mesoporous carbon/silica (MCS-SO3H) was prepared by direct sulfonation with H2SO4 solution. The silica surface of MCS-SO3H were then grafted by 3-aminopropyltrimethoxysilane to produce the acid–base catalysts (MCS-SO3H-NH2) and used as the solid catalysts in glucose conversion. The MCS nanocomposites exhibited enhanced structural, …
Synthesis Of Baicalein Derivatives As Anti-Dengue Agents, Apinya Patigo
Synthesis Of Baicalein Derivatives As Anti-Dengue Agents, Apinya Patigo
Chulalongkorn University Theses and Dissertations (Chula ETD)
Dengue, a mosquito-borne viral disease, is now considered a major international health concern, and hence the development of a new anti-dengue drug is highly desirable. Baicalein is a flavone isolated from the roots of Scutellaria baicalensis and Scutellaria lateriflora. Baicalein derivatives have been shown previously to exhibit a promising anti-dengue activity. In this study, five novel and thirteen known baicalein derivatives were synthesized via semi synthesis from baicalein with modifications at C-5, -6, -7, and -8 positions on ring A and a six-step total synthesis with modifications at the para position on the ring B with a range of electron-withdrawing …
Cellulose-Supported Fluorophore As Metal Ion Sensors, Apiwat Promchat
Cellulose-Supported Fluorophore As Metal Ion Sensors, Apiwat Promchat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Organic fluorescent ligands are attractive for qualitative and quantitative analysis of metal ions. Cellulose substrates, especially for filter paper, have been demonstrated as one of the most economical and easy to use platform for fluorescent sensors applied in on-site analysis with naked-eye observation. In this work, new series of amidoquinoline derivatives were synthesized and investigated as the fluorescent ligands for developing paper-based sensors. The sensors are used for convenient analysis either by simple naked-eye observation or an image processing software. In the first part of this dissertation, parallel solid-state synthesis on filter paper macroarray was used for rapid discovery and …
Use Of Modified Nay Zeolite As Ionophore For Perchlorate Selective Electrode, Boonyakorn Srisassawatkul
Use Of Modified Nay Zeolite As Ionophore For Perchlorate Selective Electrode, Boonyakorn Srisassawatkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
NaY zeolite is well deserved for being employed as a catalyst, adsorbent, and ion exchanger. Therefore, its ion exchange property is used in ion selective electrodes (ISEs). Commercial NaY zeolite was modified with cetyltrimethylammonium bromide (CTAB) in various concentrations (100, 150, and 200 mM), denoted them as 100, 150 and 200 SMZ, respectively. XRD, FT-IR, SEM and TGA/DTG showed good agreement of CTAB adsorption on zeolite surface. Then SMZ is used to fabricate polymeric membrane with polyvinyl chloride (PVC) plasticized with o-nitrophenyl octyl ether (o-NPOE). The best performance of ISE was exhibited at the membrane composition of 200 SMZ: PVC: …
Genetic Code Expansion Of Plastic-Degrading Enzymes For Detection Of Microplastics, Jariya Jitdee
Genetic Code Expansion Of Plastic-Degrading Enzymes For Detection Of Microplastics, Jariya Jitdee
Chulalongkorn University Theses and Dissertations (Chula ETD)
Petrochemical plastics can degrade into the size level of microplastics. One source of microplastics is polyethylene terephthalate (PET or PETE). Enzymes used to degrade PET have been reported. In our work, we wish to repurpose the activity of PET-degrading enzymes, into PET-detecting enzymes, and use the engineered enzyme for microplastic detection, via enzyme engineering to create enzyme variants which can form covalent adducts with microplastic particles. The enzyme-microplastic adduct is generated via the use of 2,3-diaminopropionic acid (DAP) derivative, which we will incorporate in place of the catalytic serine residue at the active site of I. sakeinesis—PETase via the genetic …
Modification Of Screen-Printed Carbon Electrode For Detection Of Pesticides, Kansuda Langor
Modification Of Screen-Printed Carbon Electrode For Detection Of Pesticides, Kansuda Langor
Chulalongkorn University Theses and Dissertations (Chula ETD)
Methyl parathion (MP) is an organophosphate pesticide broadly used in agriculture to protect crops and fruits from the damages caused by insects and pests. However, when it is used in large quantities, it can be potentially toxic to humans and animals, causing many poisoning effects. Moreover, its residues can also penetrate the food chain (via agriculture food products) as well as contaminating the environment, leading to air, water and soil pollution. Therefore, rapid determination and reliable quantification of trace level of MP are crucially needed for food safety and environmental monitoring. In this work, a low-cost and portable electrochemical sensor …
Chemical Constituents Of Fan-Si Abutilon Indicum Stems, Arum Restu Widyasti
Chemical Constituents Of Fan-Si Abutilon Indicum Stems, Arum Restu Widyasti
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aimed to isolate secondary metabolites from the stems of Abutilon indicum and to evaluate their α-glucosidase, pancreatic lipase, α-chymotrypsin inhibitory activity. Chromatographic fractionation of the n-hexane crude extracts led to the isolation of three known metabolite (1-3). The crude extract from all parts of the plant were evaluated for inhibitory activity on the alpha-glucosidase enzyme. The DCM-soluble roots were active with 10.2% at 25 μg/mL. The hexane and MeOH-soluble stems were active with 11.0% at 25 μg/mL and 8.0% at 0.25 μg/mL. The hexane, DCM, and MeOH-soluble leaves are active with 20.2% at 0.025 μg/mL; 20.0% at 0.025 …
Colorimetric And Fluorescent Detection Of Nucleic Acid By Styryl Dyes, Kotchakorn Supabowornsathit
Colorimetric And Fluorescent Detection Of Nucleic Acid By Styryl Dyes, Kotchakorn Supabowornsathit
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nucleic acid staining dyes are essential tools for the analysis and visualizing of DNA/RNA in vitro and in cellular applications. Although there are several commercially available dyes developed during the past few decades, the selection is still relatively limited, and they are often very costly and associated with undesirable characteristics such as toxicity. Consequently, the discovery of nontoxic, readily available dyes, with desirable and controllable optical characteristics remains important. Styryl dyes have recently gained popularity as potential biological staining agents with many desirable properties including a straightforward synthesis procedure, excellent photostability, tunable optical properties, and high responsiveness towards nucleic acid …
Adsorption Of Hydrogen Gas On Polymorphic Zirconium Dioxide Surfaces, Monrada Petchmark
Adsorption Of Hydrogen Gas On Polymorphic Zirconium Dioxide Surfaces, Monrada Petchmark
Chulalongkorn University Theses and Dissertations (Chula ETD)
Adsorption of hydrogen gas on polymorphic zirconium dioxide (ZrO2) surfaces including cubic, tetragonal and monoclinic phase denoted by c-ZrO2(111), t-ZrO2(101) and m-ZrO2(111), respectively has been investigated using the periodic density functional theory (DFT) calculation. The stabilities of perfect and oxygen vacancy defective ZrO2 surfaces are in orders: c-ZrO2(111) > t-ZrO2(101) > m-ZrO2(111) and [c-ZrO2(111)+VO] > [t-ZrO2(101)+VO] > [m-ZrO2(111)+VO], respectively. The abilities of hydrogen adsorption on perfect and oxygen vacancy defective ZrO2 surfaces are in orders: [c-ZrO2(111)+VO] (∆Eads = –4.13 eV) > [m-ZrO2(111)+VO] (∆Eads = –3.31 eV) > [t-ZrO2(101)+VO] (∆Eads = –2.91 eV) > c-ZrO2(111) (∆Eads = –1.89 eV) > m-ZrO2(111) (∆Eads = –1.67 eV) > t-ZrO2(101) (∆Eads = –0.27 …
Synthesis And Application Of Polymeric Micelles Assembled From Pentafluorophenyl Ester-Containing Amphiphilic Block Copolymers, Panittha Damsongsang
Synthesis And Application Of Polymeric Micelles Assembled From Pentafluorophenyl Ester-Containing Amphiphilic Block Copolymers, Panittha Damsongsang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Functionalizable pentafluorophenyl ester (PFP)-based polymer precursors, namely poly(pentafluorophenyl acrylate) (PPFPA) and poly(pentafluorophenyl metharylate) (PPFPMA), and zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) are the two polymers having extremely different solubility. It is therefore almost impossible to synthesize their block copolymers in a controlled manner by the conventional approach. Herein, we demonstrated, for the first time, that the synthesis and in situ formation of nanoassemblies of their diblock copolymer can be done via polymerization-induced self-assembly (PISA) using reversible addition-fragmentation chain-transfer (RAFT) dispersion polymerization. PMPC was synthesized as the first block and further employed as a macro chain transfer agent (PMPC Macro-CTA) for the synthesis …
Theoretical Study Of Ethylene Polymerization By Phenoxy-Imine Catalyst, Pavee Apilardmongkol
Theoretical Study Of Ethylene Polymerization By Phenoxy-Imine Catalyst, Pavee Apilardmongkol
Chulalongkorn University Theses and Dissertations (Chula ETD)
Reaction mechanisms of ethylene polymerization catalyzed by the phenoxy-imine (FI) and the nickel phenoxyphosphine polyethylene glycol (Ni-PEG) with alkali metals were explored using DFT calculations. For FI catalysts, the effect of group IVB transition metals substitutions was investigated. The trend of calculated activation energies (Ea) at the rate-determining step is Zr < Hf < Ti and is in good agreement with experiments. The effect of ligands of the Ti-FI-based catalysts when changing the parent nitrogen (O, N) to oxygen (O, O), phosphorus (O, P), and sulfur (O, S) ligands on activity was also monitored. The results indicated that the sulfur (O, S) ligand gives the lowest activation energy. Additionally, the reactivity of Ni-phenoxy-imine (Ni-FI)-based catalysts for polyethylene polymerization was studied. Our calculations suggested that the square planar complex of Ni-FI is more reactive than its C2 symmetric octahedral complex. For Ni-PEG(M) catalysts, the trend for activation energies of four Ni-PEG(M) systems is Li < Na < K < Cs, which corresponds to experimentally observed activities. Moreover, the roles of secondary metals in Ni-PEG catalysts in terms of steric, electronic, and electrostatic effects were elucidated. The DFT results suggested that the active catalyst should have strong cooperative metal-metal/metal-ligand interactions and less positive charge on the secondary metal. Finally, to gain insight into the design of the novel Ni-PEG catalysts with alkali-earth metals, the effect of catalyst structure on experimental activity was investigated. This work provides fundamental understandings of the reaction mechanisms for the FI and Ni-PEG(M) catalysts, which could be used for the design and development of catalysts for ethylene polymerization.
Discrimination Of Weedy Rice By Using Near-Infrared Spectroscopy Combined With Chemometrics, Sureerat Makmuang
Discrimination Of Weedy Rice By Using Near-Infrared Spectroscopy Combined With Chemometrics, Sureerat Makmuang
Chulalongkorn University Theses and Dissertations (Chula ETD)
Weedy rice is one of the most notorious weeds occurring in rice-growing areas, especially in South-East Asia. Weedy rice especially in form of paddy seed is difficult to manage and separate as they provide common features (morphological resemblance) to cultivated rice. This work presents a modification of self-organizing map (SOMs) for the classification of weedy rice from cultivated rice via in situ direct sample analysis from paddy seed using near-infrared (NIR) spectroscopy and hyperspectral NIR camera. The sample pretreatment was carried out by a cyclone vacuum machine to remove the contaminated particles and other impurities. The physical characteristics and the …
Lamellar Inorganic Solids And Biochar Nanocomposites For Sorptive Removal Of Metal Ions And Nitrophenol, Sutasinee Sutthiklub
Lamellar Inorganic Solids And Biochar Nanocomposites For Sorptive Removal Of Metal Ions And Nitrophenol, Sutasinee Sutthiklub
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the adsorbents of ternary-component composites were developed to remove various types of toxic chemicals. The selected three components are clay, MgAl-layered double hydroxide (MgAl-LDH) and biochar because they are nontoxic and low cost and also possess high adsorption capacity and high surface area. The composites were synthesized by the combination of post-pyrolysis and co-precipitation methods, and characterized by XRD and SEM-EDS. The result shows that clay and LDH particles distributed and deposited on the biochar matrix, confirming the coexistence of three phases in micrometer and nanometer scales. Ni2+, CrO42- and 4-Nitrophenol were chosen as the representatives of …
Program Development For Synthesis Plan Design Of Organic Compounds By Using Artificial Intelligence, Tawatchai Jitporn
Program Development For Synthesis Plan Design Of Organic Compounds By Using Artificial Intelligence, Tawatchai Jitporn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Computer-Assisted Synthesis Planning (CASP) is a computational tool for facilitating organic chemists to design and synthesis organic compounds by calculating the best possible synthesis pathways. Most CASP tools are commercial or closed-source software and thus, they cannot be modified to improve performance or update database. Therefore, it is our aim to develop an open-source CASP tool. Library of reaction rules that was created from the US patent database was taken from literature and was then reclassified to improve its applicability. This modified library was then used for training neural network and 2 important models were obtained for the search engine. …
Development Of Colorimetric Paper-Based Analytical Device For Cortisol Detection, Thanathip Kosawatphat
Development Of Colorimetric Paper-Based Analytical Device For Cortisol Detection, Thanathip Kosawatphat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, the detection of cortisol can play a key role in understanding stress-related diseases. Several competitive immunoassay formats have been reported for the detection of this small hormone molecule. Lateral flow immunoassay (LFIA) is one of the most widely used platforms that offer its simplicity and rapidity for such analysis. Unlike previous sensors for cortisol sensing that require complicated readers, specialized reagents, or even post-treatment methods to amplify the obtained signal, in this work, we employed a concave test zone constructed on the LFIA device (cLFIA) which can directly enhance the signal response as the flowing sample was substantially concentrated …
Effect Of Electric Field On Molecular And Electronic Structures Of Graphene With 4n-Divacancy Defect And Application On Hydrogen Gas Storage, Thanawit Kuamit
Effect Of Electric Field On Molecular And Electronic Structures Of Graphene With 4n-Divacancy Defect And Application On Hydrogen Gas Storage, Thanawit Kuamit
Chulalongkorn University Theses and Dissertations (Chula ETD)
The effect of external electric fields (EEFs) on geometries and electronic properties of graphene quantum dots (GQDs) and m-4N-divacancy defect GQDs (m-4N-GQDs) was studied using density functional theory (DFT) method with M06-2x functional and 6-31g (d) basis set. An external electric field with strength ranging from -0.035 to 0.035 atomic units (a.u.) was applied normal to the molecular plane. Three different sizes, i.e., C24H12, C54H18, and C96H24, were investigated. The metal doping in m-4N-GQDs consists of Ca, Ca2+, Cr, Cr2+, Fe, and Fe2+. Our results revealed that GQDs and m-4N-GQDs are curved under EEFs in the direction opposite to the …
Incorporating Context Into Non-Autoregressive Model Using Contextualized Ctc For Sequence Labelling, Burin Naowarat
Incorporating Context Into Non-Autoregressive Model Using Contextualized Ctc For Sequence Labelling, Burin Naowarat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Connectionist Temporal Classification (CTC) loss has become widely used in sequence modeling tasks such as Automatic Speech Recognition (ASR) and Handwritten Text Recognition (HTR) due to its ease of use. CTC itself has no architecture constraints, but it is commonly used with recurrent models that predict letters based on histories in order to relax the conditional independent assumption. However, recent sequence models that incorporate CTC loss have been focusing on speed by removing recurrent structures, hence losing important context information. This thesis presents Contextualized Connectionist Temporal Classification (CCTC) loss, which induces prediction dependencies in non-recurrent and non-autoregressive neural networks for …
Voice Impersonation For Thai Speech Using Cyclegan Over Prosody, Chatri Chuanngulueam
Voice Impersonation For Thai Speech Using Cyclegan Over Prosody, Chatri Chuanngulueam
Chulalongkorn University Theses and Dissertations (Chula ETD)
No abstract provided.
Deep Learning Approach On Symptom Questionnaire And Abdominal Radiography For Diagnosis Of Dyssynergic Defecation, Sornsiri Poovongsaroj
Deep Learning Approach On Symptom Questionnaire And Abdominal Radiography For Diagnosis Of Dyssynergic Defecation, Sornsiri Poovongsaroj
Chulalongkorn University Theses and Dissertations (Chula ETD)
Dyssynergic defecation is one of the most common causes of chronic constipation. It is a behavioral problem in which the pelvic floor muscles are unable to coordinate with the surrounding muscles and nerves to evacuate stool. Patients are required to undergo specialized tests only available at tertiary healthcare centers for diagnosis. The aim of this thesis is to develop deep learning-based models to prescreen potential patients from primary and secondary healthcare centers for further diagnostic tests by using easily obtainable data such as symptom questionnaire and abdominal radiography. First, we developed a model which uses symptom questionnaire as an input …
Spectral And Latent Representation Distortion For Tts Evaluation, Thananchai Kongthaworn
Spectral And Latent Representation Distortion For Tts Evaluation, Thananchai Kongthaworn
Chulalongkorn University Theses and Dissertations (Chula ETD)
One of the main problems in the development of text-to-speech (TTS) systems is its reliance on subjective measures, typically the Mean Opinion Score (MOS). MOS requires a large number of people to reliably rate each utterance, making the development process slow and expensive. Recent research on speech quality assessment tends to focus on training models to estimate MOS, which requires a large number of training data, something that might not be available in low-resource languages. We propose an objective assessment metric based on the DTW distance using the spectrogram and the high-level features from an Automatic Speech Recognition (ASR) model …
Data Augmentation For Thai Natural Language Processing Using Different Tokenization, Patawee Prakrankamanant
Data Augmentation For Thai Natural Language Processing Using Different Tokenization, Patawee Prakrankamanant
Chulalongkorn University Theses and Dissertations (Chula ETD)
Tokenization is one of the most important data pre-processing steps in the text classification task and also one of the main contributing factors in the model performance. However, getting good tokenizations is non-trivial when the input is noisy, and is especially problematic for languages without an explicit word delimiter such as Thai. Therefore, we proposed an alternative data augmentation method to improve the robustness of poor tokenization by using multiple tokenizations. We evaluated the performance of our algorithms on different Thai text classification datasets. The results suggested our augmentation scheme makes the model more robust to tokenization errors and can …
A Deep Learning Model For Predicting Long Non-Coding Rna And Messenger Rna With Model Interpretation, Rattaphon Lin
A Deep Learning Model For Predicting Long Non-Coding Rna And Messenger Rna With Model Interpretation, Rattaphon Lin
Chulalongkorn University Theses and Dissertations (Chula ETD)
Long non-coding RNAs (lncRNAs) play important roles in many biological processes and are found to be associated with several diseases. The development of next-generation sequencing technologies has discovered numerous unannotated transcripts. However, classifying these unannotated transcripts by using biological experiments is very time-consuming and expensive. Thus, a computational approach is considered as an alternative solution which is faster and cheaper. Many existing lncRNA identification tools are available, these tools lack an explanation of which features contributed to their prediction results. Here, we present Xlnc1DCNN, a tool for distinguishing long non-coding RNAs (lncRNAs) from protein-coding transcripts (PCTs) together with a prediction …
Adaptive Image Preprocessing And Augmentation For Disease Screening On Multi-Source Chest X-Ray Datasets, Wasunan Chokchaithanakul
Adaptive Image Preprocessing And Augmentation For Disease Screening On Multi-Source Chest X-Ray Datasets, Wasunan Chokchaithanakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Research on deep learning models for chest radiology applications has increased attention by the public. However, most works focus on developing models using in-domain data, so the significant drawback, when applied in real-world scenarios, was the mismatched data with the training set. Consequently, some models perform inferior at the deployment stage. This work focused on the effects of dataset mismatch on chest radiography and analyzed the methods the overcome the mismatch issues. The lung balance contrast enhancement technique (lung BCET) automatically identifies the lung region and normalizes the image accordingly to improve the robustness of out-of-domain data developed. Additionally, augmentation …
A Design Of Fpga Framework For Quantum Computing Simulation, Yaninee Jungjarassub
A Design Of Fpga Framework For Quantum Computing Simulation, Yaninee Jungjarassub
Chulalongkorn University Theses and Dissertations (Chula ETD)
We use FPGA to optimize the simulation of quantum computing in two aspects. (a) The if-else state is used in place of tensor product calculation. This allows the tensor product of each quantum operator to be generated in a single clock cycle. (b) The pre-calculated lookup ROM is used for estimating the sine and cosine values. This facilitates the computation of quantum gates that are related to angle. To validate our work, we implement our design in VerilogHDL. The performance is evaluated using an FPGA simulator. The result shows a dramatic improvement in the simulation process comparing to those of …
Cascading Model For Forex Market Forecasting Using Fundamental And Technical Indicator Data Based On Bert, Arisara Pornwattanavichai
Cascading Model For Forex Market Forecasting Using Fundamental And Technical Indicator Data Based On Bert, Arisara Pornwattanavichai
Chulalongkorn University Theses and Dissertations (Chula ETD)
The foreign exchange rate market is the world's biggest and most liquid financial market, and it's where all currency pairs' exchange rates are set. Since foreign exchange (Forex) rates play a critical role in financial technology and business, many researchers are now interested in forecasting them. The characteristics of Forex data, that include fluctuation, non-linearity, and random walk phenomena, make it difficult for forecasting. Several related studies integrate fundamental data (FD) and technical indicator data to generate Forex forecasting signals (TI). TI is a price pattern-based signal, whereas FD is an indicator of the country's economic conditions. Nevertheless, when it …