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Prediction Model Of Water Quality In Chaophraya River Using Artificial Neural Network, Weeris Treeratanajaru
Prediction Model Of Water Quality In Chaophraya River Using Artificial Neural Network, Weeris Treeratanajaru
Chulalongkorn University Theses and Dissertations (Chula ETD)
No abstract provided.
Enhancing Captcha Using Eye Movement, Apichai Siripitakchai
Enhancing Captcha Using Eye Movement, Apichai Siripitakchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
CAPTCHA is a method designed to prevent automatic registration and access. It can distinguish between real human and automated program (BOT). CAPTCHA connects to a server and then starts human verification process. The user must answer a question correctly or follow an instruction in order to get access to the system. However, there are some problems occurred to users. For example, the verification text is too distorted that even real humans do not understand or the effectiveness of preventing an automated computer program is doubted. From these reasons, researchers are still developing CAPTCHA to make it better and more effective. …
High Capacity Image Steganography Tolerating Image Compression, Eittipat Kraichingrith
High Capacity Image Steganography Tolerating Image Compression, Eittipat Kraichingrith
Chulalongkorn University Theses and Dissertations (Chula ETD)
Nowadays, data privacy becomes more important. Most of the existing data protection schemes based on cryptography cannot hide the existence of secret data. Thus, a steganography approach plays an important role to handle this problem. Image steganography can be categorized into two methods which are baesd on spatial domain and transform domain. Methods using spatial domain have high embedding capacity but they are not robust to image compression. On the other hand, methods using transform domain usually work with image compression but have low embedding capacity. In recent image steganography research, many transform domain methods are based on JPEG format …
Biological-Like Memory Allocation Scheme Simulation, Gasydech Lergchinnaboot
Biological-Like Memory Allocation Scheme Simulation, Gasydech Lergchinnaboot
Chulalongkorn University Theses and Dissertations (Chula ETD)
When Gordon Moore observed the number of transistor increasing pattern while memory bandwidth could not catch up with processing unit performance, this diverging rate kept stretching out to create what eventually transpired to be Memory Wall. This consequence becomes a major performance bottleneck. Many bottleneck elimination approaches have been attempted. They incorporate considerable overhead and high complexity. This research proposes a novel memory allocation scheme that employs biological behavioral principles of the living creatures. At the principal construct of their life form lives the cells having limited resources, yet passively operates with little overhead. The proposed method imitates this unicellular …
Discovery Of Relation Between Listeria And Other Bacterial Contamination Using Classification Refinement Technique, Napas Jeamchotpatanakul
Discovery Of Relation Between Listeria And Other Bacterial Contamination Using Classification Refinement Technique, Napas Jeamchotpatanakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
People often use chicken to prepare their diary meal which creates a great demand for food producers and exporters in Thai food industry. Thailand is ranked fourth in chicken exporters in the world. Standards on chicken meat regulations differ from country to country. One commonality remains: controlling the bacteria that can affect human life, particularly pregnant women and the unborn. One of the important bacteria is called Listeria which receives high attention for the industry to prevent their contamination in chicken. A microbiological test is usually conducted to analyze the data from industry. However, the microbiological test is incapable of …
Diagnosis Of Heart Disease Using Mixed Classifier, Sarawut Meesri
Diagnosis Of Heart Disease Using Mixed Classifier, Sarawut Meesri
Chulalongkorn University Theses and Dissertations (Chula ETD)
At present, there are many studies related to the use of medical information, in order to assist in the analysis and diagnosis of the patients. In the field of computer science, there are methods to assist in analysis and diagnosis of the various diseases using the data mining techniques. Data mining is a popular technique used for analyzing a large number of data, to find the relationship of the hidden information in those data and applied for the benefits of the organization. Classification technique based on the supervised learning is one of the data mining techniques, which divides the dataset …
Energy Aware Scheduling For Heterogeneous Mobile Task Computing, Vittayasak Rujivorakul
Energy Aware Scheduling For Heterogeneous Mobile Task Computing, Vittayasak Rujivorakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
The problem of scheduling a set of dependent tasks from a user mobile device to several servers in communication cells while the user is moving along these cell in various speed is studied in this thesis. The challenging issue is the execution speed of each server and the speed of user's movement are not compatible. This leads to the difficulty of assigning and finishing the subset of scheduled dependent tasks to each server within the limitation of execution time during passing a cell. Another concern involved this study is the constraints on the length of makespan in terms of minimum …
Land Use And Land Cover Change Of Chanthaburi Watershed Following 1999, 2006 And 2013 Floods, Chuti Chatewutthiprapa
Land Use And Land Cover Change Of Chanthaburi Watershed Following 1999, 2006 And 2013 Floods, Chuti Chatewutthiprapa
Chulalongkorn University Theses and Dissertations (Chula ETD)
The application of remote sensing (RS) and Geographic Information System (GIS) has become an effective tool and widely used in monitoring the environment on the earth surface. In this study, Landsat imageries were used as a data to deal with the assessment of land use and land cover changes (LULC) before and after the 3-year floods in 1999, 2006 and 2013. The images were classified by supervised classification process and it can be identified as 9 classes consisting of paddy field, field crop, para rubber, orchard, aquacultural land, forest land, mangrove forest, urban and built-up area, and water bodies. The …
Geochemistry Of Petroleum Potential Source Rock In Tak Fa Formation, Phetchabun Province, Supawich Fuengfu
Geochemistry Of Petroleum Potential Source Rock In Tak Fa Formation, Phetchabun Province, Supawich Fuengfu
Chulalongkorn University Theses and Dissertations (Chula ETD)
Since 1962, petroleum exploration was begun in Khorat Plateau until now (2018). Nam Phong and Sin Phu Horm are two onshore petroleum commercial fields. Gas and condensate have been accumulated in Permian carbonate Pha Nok Khao Formation. Upper Carboniferous - Upper Permian in Saraburi Group was predicted to a petroleum source rock beneath the Khorat Plateau. This study analyses potential source rock in Khao Khwang Platform of Tak Fa Formation as Middle Permian sedimentary rock by nine outcrop samples from Bueng Sam Phan, Chon Daen and Nong Phai areas, Phetchabun province. Petroleum geochemistry methods are used to determine petroleum potential …
Regional Development Models With Clean Coal Power Plants, Christoph Casimir Odermatt
Regional Development Models With Clean Coal Power Plants, Christoph Casimir Odermatt
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis examines clean coal technology to be used in Thailand in three studies. The economic impacts on the economic structure of southern Thailand are forecasted with the input-output method. Further, the relative levelized costs of clean coal energy relative to its amount of carbon equivalent emissions are compared to other technologies and their carbon equivalent emissions in order to compute a carbon certificate price. Lastly, the costs of the solar subsidy on the end consumer is calculated in different scenarios. The results suggest that there may be slight changes in the economic structure in southern Thailand with increases in …
Asset Pricing And Network Topology, Harnchai Eng-Uthaiwat
Asset Pricing And Network Topology, Harnchai Eng-Uthaiwat
Chulalongkorn University Theses and Dissertations (Chula ETD)
This dissertation provides new empirical evidence for the relationship between network structure and asset returns in US, international markets, and Thailand. Previous studies find that a network of return correlations provides the meaningful economic taxonomy of the equity market. This finding makes the network structure a suitable channel through which an idiosyncratic shock propagates. This network feature can eliminate or amplify the idiosyncratic shock on the system-wide level. Therefore, the diversifying argument of the capital asset pricing models is not always true as the idiosyncratic shock becomes more significant when interacting with the network measures. Based on this idiosyncratic shock …
Economic Policy Uncertainty And Carry Trade Strategy, Tiranan Sanguanjeen
Economic Policy Uncertainty And Carry Trade Strategy, Tiranan Sanguanjeen
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study provides a comprehensive analysis of the impact of economic policy uncertainty on carry trade. Based on 24 countries (both emerging and developed markets) during the past 17 years, the paper considers five strategies of carry trade investment (i.e. positive carry, carry to risk, yield slope, policy change and valuation), three methods of portfolio constructions (equal weight, risk parity and mean variance optimization), and four types of economic policy uncertainties (US, Japan, EU and Global). Based on vector autoregressive model, it is found that US and Japan economic policy uncertainties have most impact on carry trade return. However, direction …
Multiple Face Detection And Recognition On Embedded Computer Vision System, Savath Saypadith
Multiple Face Detection And Recognition On Embedded Computer Vision System, Savath Saypadith
Chulalongkorn University Theses and Dissertations (Chula ETD)
Face recognition is widely used in many applications such as biometric for authentication, surveillance system, user-identification, and personalized technology. The state-of-the-art algorithm based on Convolutional Neural Network (CNN) can achieve up to 99% of recognition accuracy. However, there is a limitation to implement the CNN based technique into embedded system to recognize multiple face in real-time as it requires extensive computation. In this thesis, we propose a framework for multiple face recognition which consists of face detection algorithm, face recognition, and tracking. Our face recognition algorithm based on state of the art deep CNN with small computational parameters. The tracking …
Determination Of Waste Treatment Fee Pricing Mechanism For Municipal Solid Waste By Mechanical Biological Treatment Method Utilising The Public Private Partnership Model In Thailand, Adrian Paul Raj
Chulalongkorn University Theses and Dissertations (Chula ETD)
Private participation in the development of municipal solid waste treatment projects through public-private partnership models accelerate the implementation of sustainable treatment technologies such as Mechanical Biological Treatment (MBT) facilities within developing countries without creating excessive burden to government infrastructure investment. The introduction of preset pricing mechanism to regulate potential waste treatment fee structure based on pre-determined project internal rate-of-return mitigates multi-party risks, such as the potential developer project losses or the opportunity to profiteer. Research encompasses technical assessment of project requirements for implementation of required technologies, commercial analysis of project capital expenditure (CAPEX), operational expenditure (OPEX) and assessment of revenue …
A Comparative Assessment Of Self-Consumption Support Schemes For Rooftop Pv Systems In Thailand, Kespanerai Kokchang
A Comparative Assessment Of Self-Consumption Support Schemes For Rooftop Pv Systems In Thailand, Kespanerai Kokchang
Chulalongkorn University Theses and Dissertations (Chula ETD)
The growth in the adoption of solar photovoltaic (PV) power generation systems has been accelerating around the world, contributing to the debate about the future of policy and regulation in a high distributed energy resources future. Thailand is one of the leaders in solar investment in Southeast Asia. It has recently shifted its policy framework from subsidizing power export through feed-in tariffs toward a policy that is focused on supporting self-consumption of PV electricity. There are three possible forms of self-consumption support scheme: net metering, net billing, and self-consumption only. Net metering and net billing are electricity policies to assign …
The Socio-Economic Impact Of Iuu-Fishing And Its Countermeasures On Small Scale Fishermen In Thailand : A Case Study Of Baan Khan Kradai, Ao Noi, Prachuap Kiri Khan, Roman Zwoelfer
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study investigates the socio-economic effects of Illegal, Unreported and Unregulated fishing (IUU-fishing) on households of small scale fishermen, whose income derives almost entirely from fishing. The research question is "What are the socio-economic impacts of IUU-fishing and government's countermeasures on Thai fishing communities, in particular small scale fishermen's households, before and after 2015?". A mixed quantitative and qualitative approach was chosen to better grasp the complexity of fishing-related changes to household income and by the case study of a small scale fishing community in Ao Noi Subdistrict of Prachuap Kiri Khan Province. This resulted to a general understanding of …
Drivers And Constraints Of Conversion To Organic Farming In The Kingdom Of Bhutan, Parladh Mahat
Drivers And Constraints Of Conversion To Organic Farming In The Kingdom Of Bhutan, Parladh Mahat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Organic farming is one of the several approaches towards environmental conservation and aims to increase agricultural production and household income for small-scale farmers to enable them to come out of poverty and improve livelihood. The objective is to investigate the key drivers and constraints in conversion to organic farming for domestic organic certified and non-certified but organic farmers and provide policy recommendation to government and relevant agency. The survey data of 146 respondents comprising of certified organic (n=47) and non-certified (n=99) were collected from Gasa district of Bhutan during the month of October 2017. The data analysis includes the use …
Paleo Sea-Level Change Of Laem Pho, Amphoe Chaiya, Changwat Surat Thani, Sinenard Polwichai
Paleo Sea-Level Change Of Laem Pho, Amphoe Chaiya, Changwat Surat Thani, Sinenard Polwichai
Chulalongkorn University Theses and Dissertations (Chula ETD)
The study of beach ridges plains at Laem Pho study area in Amphoe Chaiya, Changwat Surat Thani is aimed to investigate coastal geomorphology and sedimentology to analyze the history of Holocene sea level change. The methodology starts with satellite image interpretation of landform for field survey planning, then, geomorphologic map was done for locating sample collection sites. Grainsize analysis and Optically Stimulated Luminescence (OSL) dating were carried out. As a result, the study area has dominant landforms of beach ridge plains and sand spit oriented in southeast direction correspondence with southeast longshore current. Source of sediment supply to this coastal …
Microencapsulation Instant Coffee By Spray Drying Using Hydrolysed Konjac Glucomannan, Desi Sakawulan
Microencapsulation Instant Coffee By Spray Drying Using Hydrolysed Konjac Glucomannan, Desi Sakawulan
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research is aimed at finding a suitable wall material from konjac glucomannan to shield antioxidant compounds in coffee extract along with appropriate condition of spray drying to produce microencapsulated instant coffee. There are two steps of study. In the first step, two types of konjac powder (A. muelleri and A. bulbifer) and different concentrations of mannanase enzyme were used to investigate the viscosity reduction of konjac glucomannan hydrolysate (KGMH). It is found that mannanase at 38,000 units per gram substrate was able to lower the viscosity of A. muelleri solution to less than 100 m.Pa.s, while A. bulbifer remained …
Halophilic Bacteria From Salty Fermented Foods And Its Bacteriocin Encoding Gene Expression To Use As Biocontrol Agent Against Staphylococcus Aureus In Salt Added Foods, Vishal Chhetri
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research was aimed to isolate, select and apply bacteriocin producing halophilic bacteria from salty fermented foods, Plara (Thai traditional salty fermented fish) and soya sauce as bio-control agent in foods. The isolates having inhibitory activity against different strains of Staphylococcus aureus were selected, identified and characterized prior to application as protective starter in food models. Bacterial communities of Plara and soya sauce samples were studied by two methods, a cultural dependent and cultural independent method (Reverse Transcriptase PCR DGGE (Rev-T PCR-DGGE)), and subsequently sequenced by 16s rDNA analysis. Halanaerobium spp. in Plara and Staphylococcus gallinarum in soya sauce were …
Rapid Quality Determination Of Mulberry Leaf Tea During Storage Using Electronic Nose And Electronic Tongue, Anchalee Ruengdech
Rapid Quality Determination Of Mulberry Leaf Tea During Storage Using Electronic Nose And Electronic Tongue, Anchalee Ruengdech
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study was aimed to develop rapid methods based on electronic nose (e-nose) and electronic tongue (e-tongue) to determine the quality attributes and phytochemicals of mulberry leaf tea. This study was divided into three parts: (1) to determine the effect of cultivar on the quality attributes and phytochemicals of mulberry leaf tea, (2) to evaluate the effect of packaging and storage time on quality attributes and phytochemicals of mulberry leaf tea, and (3) to employ e-tongue combined with chemometrics for prediction of phytochemicals and antioxidant activity of mulberry leaf tea. Mulberry leaf tea prepared from three different mulberry cultivars including …
Assessment Of Cadmium Migration Into Groundwater In Mae Sot District, Tak Province Using Monte Carlo Technique, Pongsathorn Thunyawatcharakul
Assessment Of Cadmium Migration Into Groundwater In Mae Sot District, Tak Province Using Monte Carlo Technique, Pongsathorn Thunyawatcharakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Mae Sot is a district in Tak province that confronts Cd contamination within the area. The target organs for Cd exposure was kidneys and skeletal system which could lead to severe health effects such as renal dysfunction, osteoporosis, bone softening, Itai-Itai disease, and lung cancer. The intention of this study was to examine the sorption behavior of nine soil samples in the study area and applied Monte Carlo technique that would increase model efficiency for Cd migration in to the soil profile. Batch adsorption experiments were performed and fitted with the adsorption isotherms as follows: Linear, Langmuir, and Freundlich isotherms. …
The Effect Of Edta-Application To Heavy Metals Phytoremediation By Vetiver, Ramida Wasino
The Effect Of Edta-Application To Heavy Metals Phytoremediation By Vetiver, Ramida Wasino
Chulalongkorn University Theses and Dissertations (Chula ETD)
Contaminated soil with heavy metals includes Pb, Zn, and Cd were remediated by phytoremediation with vetiver to solved the problem in Thailand. This study compared the ability of two species of vetiver (i.e., Songkhla 3 and Prachuap Khiri Khan) in absorbing Pb, Zn, and Cd in contaminated soils and study the effect of EDTA application. After the experiment, Toxicity Characteristic Leaching Procedure (TCLP) test, Allium test, and seed germination were used to determined the toxicity of remediated soil. In this study, 5 mmol of ethylenediaminetetraacetic acid (EDTA) was used to improve the solubility of heavy metals in soil which leads …
Time Series Pattern Discovery Techniques For Well-To-Well Log Correlation, Chanchai Apiwatsakulchai
Time Series Pattern Discovery Techniques For Well-To-Well Log Correlation, Chanchai Apiwatsakulchai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Well log data is one of the most abundant data sources for subsurface characterization since almost all drilled wells are logged. Subsurface characterization requires correlated well log information. Processes to help perform well-to-well log correlation have been developed in this study based on the two approaches: pattern matching and pattern discovery. Pattern matching focuses on finding a known pattern of interest in uncorrelated wells. The use of Euclidean, Hamming, and Levenshtein distances in similarity measurement, Piecewise Aggregate Approximation (PAA), and Symbolic Aggregate approXimation (SAX) data representation helps create reduced-resolution while maintains the main characteristics of the signals. Multi-resolution analysis provides …
Apatite Fission Track Dating Of Mesozoic Siliciclastic Rocks From Khorat Group In Phu Phan Mountain Range, Northeastern Thailand, Apivut Veeravinantanakul
Apatite Fission Track Dating Of Mesozoic Siliciclastic Rocks From Khorat Group In Phu Phan Mountain Range, Northeastern Thailand, Apivut Veeravinantanakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Field and remote-sensing investigations have been performed for mapping the Mesozoic siliciclastic rocks of the Phu Phan Ranges (PPR), northeastern Thailand. Stratigraphically, the PPR study area has been remapped and is occupied by 5 distinct successive formations, including the Phu Kradung Formation with the average thickness of 93 m, the Phra Wihan Formation with the average thickness of 64 m, the Sao Khua Formation with the average thickness of 63 m, the Phu Phan with the average thickness of 84 m, and the Khok Kruat with the average thickness of 49 m. Results on field and remote sensing analyses reveal …
Ancient And Modern Fluvial Geomorphology Of Meandering System From Upstream Area Of The Mun River, Changwat Nakhon Ratchasima, Parisa Nimnate
Ancient And Modern Fluvial Geomorphology Of Meandering System From Upstream Area Of The Mun River, Changwat Nakhon Ratchasima, Parisa Nimnate
Chulalongkorn University Theses and Dissertations (Chula ETD)
At the southwestern rim of the Khorat Plateau, the upstream part of the Mun River flows through clastic sedimentary rocks leading to a massive amount of sand was transported via the Mun River to downstream. The Mun Bon Dam was constructed in 1986, and it would be effect more or less on river system. Therefore, the aim of this thesis is to analyze the geomorphological changes before and after the Mun Bon Dam construction. Moreover, the sedimentary facies from geological and shallow geophysical surveys were characterized. The geomorphic parameters was analyzed from series of aerial-photo and satellite image which were …
Human Health Risk Assessment Of Cadmium Exposure Through Rice Consumption In Mae Tao, Mae Sot District, Tak Province, Parin Suwatvitayakorn
Human Health Risk Assessment Of Cadmium Exposure Through Rice Consumption In Mae Tao, Mae Sot District, Tak Province, Parin Suwatvitayakorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Mae Tao sub-district is located in the Mae Tao watershed, an important Cd contaminated area in Thailand. This study was conducted to i) investigate total Cd concentration in rice from households in the Mae Tao sub-district and ii) estimate health risks from Cd exposure through rice consumption. A total number of 159 rice samples were collected from households in all 6 villages of the Mae Tao sub-district. These rice samples were digested with concentrated nitric acid and analyzed by the inductively coupled plasma mass spectrometry (ICP-MS). Biodata information and rice consumption behavior were surveyed from the local residents at the …
Technical Efficiency Of Private Clinics Under Universal Coverage Scheme In Bangkok, Thailand, Pimpitcha Kangyang
Technical Efficiency Of Private Clinics Under Universal Coverage Scheme In Bangkok, Thailand, Pimpitcha Kangyang
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aimed to measure technical efficiency of 88 private clinics under Universal Coverage Scheme (UC) in Bangkok in fiscal year 2017 and to identify the factors affecting their technical efficiency. The study was divided to two parts. The first part was measuring of technical efficiency with data envelopment analysis (DEA) and the second part was identifying the factors affecting efficiency with regression analysis using Tobit model. The result of DEA under a variable return to scale assumption showed that 84 private clinics under UC (95.45 percent of the target of study) were operating on pure technical efficiency frontier (VRSTE), …
Technical Efficiency Of Public District Hospitals In Vietnam, Thi Binh Lam
Technical Efficiency Of Public District Hospitals In Vietnam, Thi Binh Lam
Chulalongkorn University Theses and Dissertations (Chula ETD)
The objectives of this study aimed to evaluate the Technical Efficiency of public district hospitals in Vietnam and to determine factors affecting the hospitals' efficiency. Input-Oriented Data Envelopment Analysis (DEA) model was applied to estimate the technical efficiency scores among 52 public district hospitals in 6 provinces of Vietnam in 2014. Then, Tobit regression model was employed to explore the determinant factors. Results of the DEA indicated that there were considerable variations of efficiency scores in terms of return to scale assumptions. The average variable return to scale technical efficiency (VRSTE) and constant return to scale technical efficiency (CRSTE) were …
Increasing Profit By Rice Export Reduction Among Union Members, Narabhatra Sangmanacharoen
Increasing Profit By Rice Export Reduction Among Union Members, Narabhatra Sangmanacharoen
Chulalongkorn University Theses and Dissertations (Chula ETD)
Over the past decades, OPEC which coordinates petroleum policies among members has agreed to cut supply to raise oil price. With a consensus elasticity of -0.13, oil is an inelastic commodity, a reduction in production results in a huge increase in price. It is noticeable that OPEC can increase oil price because they altogether possess a large amount of global oil supply. It is interesting whether this strategy can be used with rice to increase its price by reducing its supply. Because rice elasticity ranges between -0.51 and -0.13, rice is also an inelastic commodity. Although rice and oil have …