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2019

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Heuristics Used In Credibility Judgment Of Health Information On Facebook, Yaninee Petcharanan Jan 2019

Heuristics Used In Credibility Judgment Of Health Information On Facebook, Yaninee Petcharanan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Facebook users worldwide had been facing challenges of information credibility. This study aimed to address this issue among Thai Facebook users by focusing on health information in particular, through a lens of heuristic approach. Data were collected from 50 informants by in-depth interviews and 480 responses from online surveys. All participants were at least 18 years old with a minimum of one year experience in using Facebook. The results revealed three different processes and five heuristics, namely, reputation heuristic, authority heuristic, expectancy violation heuristic, persuasive intense heuristic, and bandwagon heuristics that participants adopted when making a credibility judgment of health …

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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 …

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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 …

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Grid-Friendly Dispatch Strategy Of Pv Generation System With Battery Energy Storage, Sarute Srisontisuk Jan 2019

Grid-Friendly Dispatch Strategy Of Pv Generation System With Battery Energy Storage, Sarute Srisontisuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

High PV penetration reduces stability tolerance due to the lower of system inertia and system ramp capability. To handle higher PV penetration issues, the system operator and PV owners should consider the operation improvement. For the system operator, critical system ramp capability with respect to PV penetration ratio can be useful to determine the lower bound of system ramp capability for handling N-1 contingency and expected disturbances. In the case study, test results reveal that the system can operate securely with PV penetration ratio up to 40%, in which it will require system ramp capability in the range of 0.05-0.09 …

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Influence Of Curved Root Canal On Retreatment Efficacy Of Bioceramic Sealer, Kasemsun Sujaritwanit Jan 2019

Influence Of Curved Root Canal On Retreatment Efficacy Of Bioceramic Sealer, Kasemsun Sujaritwanit

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study evaluated the influence of a curved root canal on the retreatment efficacy of root canals sealed with bioceramic sealer. 60 mandibular molars were divided into 4 subgroups of severely curved canal filled with AH Plus, slightly curved canal filled with AH Plus, severely curved canal filled with BioRoot RCS and slightly curved canal filled with BioRoot. Two weeks after root canal obturation, retreatment was performed with WaveOne Gold Primary and ProTaper Next X3 following with passive ultrasonic irrigation. The retreatment efficacy parameters were regaining canal patency, retreatment time and residual filling material. MicroCT and confocal microscope were used …

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Decision Support System For Supplier Selection In Gas Pipeline Industry, Kawinkorn Ampornmaha Jan 2019

Decision Support System For Supplier Selection In Gas Pipeline Industry, Kawinkorn Ampornmaha

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this research was to study and analyse both the quantitative and qualitative decision criteria for pipeline fabrication supplier selection in the gas pipeline industry in Rayong, Thailand. The decision-making process was analysed by the Analytic Hierarchy Process technique or AHP and computed using SpiceLogic software. The data collection was carried out by providing questionnaires to experts and specialists at the management level. It was found that the main factors were quality, technical capability, delivery, cost and financial stability. All the main factors were considered with the decision-making process for purchasing and selecting with the best supplier. The …

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Strategic Supplier Selection:The Case Of International Food Trading Company, Natchanok Paramaporn Jan 2019

Strategic Supplier Selection:The Case Of International Food Trading Company, Natchanok Paramaporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of the research project is to develop strategic supplier selection system for an international food trading company using the Analytic Hierarchy Process (AHP). The products involved are canned food for worldwide export. The decision makers consist of a president and two marketing managers. The chosen decision criteria listed by weight of important are ‘Export Capability’ (54%), ’Pricing Policy’ (28%), ‘Technological Catch-up’ (10%), ‘Ethical Practices’ (5%), and ‘Environmental Management’ (3%). The sub-criteria chosen are ‘Number of Food Safety Certificate’ (54%), ‘Net Selling Price’ (23%), ‘Automation in Production Process’ (8%), ‘Payment Terms’ (5%), ‘Worker’s Safety and Health’ (4%), ‘Adverse Weather …

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Preventive Measures For Project Schedule Control Of Combined Cycle Gas Turbine Power Plant, Pakorn Prabhawong Jan 2019

Preventive Measures For Project Schedule Control Of Combined Cycle Gas Turbine Power Plant, Pakorn Prabhawong

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objectives of this research are to analyse the construction critical paths of the combined cycle gas turbine power plant projects and to determine the delay preventive measures for project schedule control. First, the planned and actual construction schedules of the combined cycle gas turbine power plants have been studied and analysed to see their critical paths and also the near-critical path which could potentially become critical. Construction schedules of four power plants constructed in Thailand have been obtained and analysed. Their capacities and main equipment arrangement are summarized in Chapter 5.1. The common work breakdown structures have been set …

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Big Data Analytics For Improving Customer Win-Back Rate In Townhome Segment, Warot Lilahajiva Jan 2019

Big Data Analytics For Improving Customer Win-Back Rate In Townhome Segment, Warot Lilahajiva

Chulalongkorn University Theses and Dissertations (Chula ETD)

Thailand’s real-estate market is now facing with negative growth, where most developers are encountered with challenges in generating satisfactory revenue, particularly from new customers. In order to improve the revenue stream, customer win-back approach that focuses on current customers in the sales funnel and re-engages them by offering more attractive residential projects is therefore initiated. In particular, we focus on the development of predictive analytics model that potentially increases customer win-back rate by exploring the current databases, identifying significance for win-back (based on past performance), and testing the resulting predictions via several machine learning algorithms. The proposed method returns a …

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Development Of Flotation Enhanced Stirred Tank (Fest) Process For Petroleum Hydrocarbons Removal From Drill Cuttings, Marina Phea Jan 2019

Development Of Flotation Enhanced Stirred Tank (Fest) Process For Petroleum Hydrocarbons Removal From Drill Cuttings, Marina Phea

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work aims to develop the treatment process for the removal of total petroleum hydrocarbons (TPH) from DC by using the combination of air floatation and stirring processes, called Flotation Enhanced Stirred Tank (FEST). Initially, stirring, induced air flotation (IAF), and dissolved air flotation (DAF) are individually investigated over DC washing. Afterward, the combination process between “stirring-DAF” and “stirring-IAF-DAF” are continuously observed for finding the better conditions of TPH removal efficiency. To optimize the operational terms of the treatment process, the Design of Experiment (DOE) is applied to design the experimental conditions within the central composite design-response surface methodology (CCD-RSM). …

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Offshore Crew Boat Sailing Time Prediction Models, Atiporn Chongterdtoonskul Jan 2019

Offshore Crew Boat Sailing Time Prediction Models, Atiporn Chongterdtoonskul

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, the relationship between travelling time of crew boats and the potential related factors was studied to improve prediction model for travelling time calculation. According to lack of data analysis, the existing calculation method had very high forecast error for crew boat’s morning route which is the main route for boat A and boat B. The selected variables were total distance and boat speed as internal factors while using significant wave height, wave direction, wind speed, and wind direction as external factors. 2017-2019 data were used in this analysis by dividing into 2017-2018 as train and validate data. …

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Customer Churn Prediction For A Software-As-A-Service Inventory Management Company, Phongsatorn Amornvetchayakul Jan 2019

Customer Churn Prediction For A Software-As-A-Service Inventory Management Company, Phongsatorn Amornvetchayakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis proposes customer churn prediction model for a Software-as-a-Service inventory management company in Thailand. Software-as-a-Service is the fast growing and high market values industry as a new emerging online business. Customer churn is a critical measure for this business. Thus, this thesis focuses on seeking a customer churn prediction model specified for a Software-as-a-Service inventory management company in Thailand which is facing a high churn rate issue. This thesis executes the prediction models with four machine learning algorithms: logistic regression, support vector machine, decision tree and random forest. The results show that the optimized decision tree model is capable …

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Improvement Of Forex Pairs Trading Strategy With Machine Learning Algorithms, Ronnachai Jirapongpan Jan 2019

Improvement Of Forex Pairs Trading Strategy With Machine Learning Algorithms, Ronnachai Jirapongpan

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis aims to study machine learning to improve the trading performance of pairs trading strategy. Pairs trading strategy is one of the most well-known algorithm trading developed in the 1980s by a group of scientists and mathematicians. The concept of the pairs trading strategy is to exploit the mispricing of two equities which their prices tend to move in the same manner. When the algorithm captures the mispricing behavior by equations or indicators, traders open a short position on the equity which its price is relatively higher than the equilibrium and open long position of the other equity. If …

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Ict Development And Wage Premiums Across Countries, Hongwu Dai Jan 2019

Ict Development And Wage Premiums Across Countries, Hongwu Dai

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study examines the effect of ICT on wage premium, by using data from 64 countries during the period 2010–2016. The Fixed Effect Model (FEM) is employed to study the relationship between ICT development and income inequality, by using two dependent variables: the conventional wage premium and wage premiums for ICT-intensive occupation. The main findings are: 1) the wage premium in countries with low levels of ICT development is relatively higher; 2) the development of ICT has a positive relationship with the wage premium; 3) the roles of the three sub-indexes of ICT development are different: ICT access shows a …

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Machine Vision Integrated Three-Dimensional Printing System, Chaiwuth Sithiwichankit Jan 2019

Machine Vision Integrated Three-Dimensional Printing System, Chaiwuth Sithiwichankit

Chulalongkorn University Theses and Dissertations (Chula ETD)

Three-dimensional printing has been a widespread solution of fabricating geometrical customized products. Any 3D printed product is normally fabricated at a position defined with respect to the coordinate system of the corresponding 3D printer. So, the 3D printing cannot be conveniently implemented in some fabricating applications in which fabricating positions are commonly constrained to some physical references, e.g., architecture construction, surface restoration, food decoration, etc. This research aimed to integrate the 3D printing with machine vision, which is vastly used for guiding robotic systems to operate at desirable positions constrained to physical objects. Hence, the 3D printing can be conveniently …

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Path Following And Obstacle Avoidance For Autonomous Vehicle Based On Gnss Localization, Kanin Kiataramgul Jan 2019

Path Following And Obstacle Avoidance For Autonomous Vehicle Based On Gnss Localization, Kanin Kiataramgul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Nowadays, many systems, formerly operated by human beings, are now developed to minimize user control effort. One outstanding system that receives close attention is the autonomous driving system. However, several autonomous driving systems that are currently developed utilize expensive sensing devices, e.g., camera and laser scanner. Moreover, these devices cannot be solely employed but a high-performance processing unit is also required. These pricey components result in an expensive system that does not worth to be used in some practical applications. Therefore, this research intends to utilize other low-cost sensing devices so that the final price of the developed system can …

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Production Of Bio-Jet Fuel From Palm Fatty Acid Distillate Over Bi-Functional Copd/Hzsm-12 Catalysts, Jarujit Chaowichitra Jan 2019

Production Of Bio-Jet Fuel From Palm Fatty Acid Distillate Over Bi-Functional Copd/Hzsm-12 Catalysts, Jarujit Chaowichitra

Chulalongkorn University Theses and Dissertations (Chula ETD)

Jet fuel is one of the major products from a petroleum refinery, its combustion emissions contribute to global warming. Therefore, bio-jet fuel is introduced to solve this problem. Palm fatty acid distillate (PFAD) is an interesting feedstock for bio-jet fuel production via three reactions including deoxygenation, hydrocracking, and isomerization. In this study, the monometallic (Co and Pd) and bimetallic (CoPd and NiPd) supported on HZSM-12 zeolite with various metal loadings and bimetallic CoPd with various zeolite supports (HZSM-12, HZSM-5, and HY) were investigated in a continuous flow trickle bed reactor. The presence of bimetallic CoPd on HZSM-12 zeolite support enhanced …

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The Study Of Sulfur Compounds For Oils Fingerprinting Application, Titiparn Prasantongkolmol Jan 2019

The Study Of Sulfur Compounds For Oils Fingerprinting Application, Titiparn Prasantongkolmol

Chulalongkorn University Theses and Dissertations (Chula ETD)

Oil spills are one of the serious problems to marine and coastal environment worldwide. Besides the known incidents, a number of oil spills are unknown, which may come from both accident and unauthorized drainage. Moreover, the spills cause tarball to arise on the beach and the origin of tarballs are still subtle. Thus, the development of oil fingerprinting is important in order to identify the origin of oil spills and tarballs. Generally, the current standard technique is using GCxGC-TOFMS to analyze the biomarker compounds in oil such as hopane groups. However, this technique is expensive and requires long time for …

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Continuous Synthesis Of Biodiesel And Glycerol Ether Using Homogeneous And Heterogeneous Catalysts, Natta Rattanapanya Jan 2019

Continuous Synthesis Of Biodiesel And Glycerol Ether Using Homogeneous And Heterogeneous Catalysts, Natta Rattanapanya

Chulalongkorn University Theses and Dissertations (Chula ETD)

In our study, a mixture of p-toluenesulfonic acid and sulfuric acid (TsOH-H2SO4) as a catalyst showed a good performance in transesterification of palm oil (PO) with methanol and etherification of biodiesel with isobutylene. For biodiesel production, the catalyst noticeably accelerated the reaction faster than TsOH and H2SO4 alone and also gave up to 99.8% of the conversion. Etherification of biodiesel with isobutylene in the etherification process using isobutylene/glycerol molar ratio 6:1 at 70°C, in the period of 5 h reaction time, gave high selectivity to produce DTBG and TTBG (81.4%). Furthermore, the catalyst can be reused for 6 cycles of …

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Electrospun Nylon 6,6 Nanofibers Functionalized With Β-Cyclodextrin As Solid Phase Extraction Sorbent For Determination Of Parabens, Tassanee Kuakul Jan 2019

Electrospun Nylon 6,6 Nanofibers Functionalized With Β-Cyclodextrin As Solid Phase Extraction Sorbent For Determination Of Parabens, Tassanee Kuakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, electrospun nanofibers of nylon 6,6 functionalized with β-cyclodextrin (nylon 6,6/β-CD) were fabricated and applied as a sorbent in solid-phase extraction (SPE) for determination of parabens in water. The electrospinning parameters such as polymer concentration, nylon 6,6/β-CD ratio, and electric field strength were investigated in order to obtain uniform nanofibers. The morphology and physical properties of obtained fibers were characterized by scanning electron microscope (SEM), Fourier transforms infrared spectroscopy (FTIR), and BET surface area analysis. The electrospun nylon 6,6/β-CD nanofibers were achieved with diameter in the range of 120 - 150 nm. The additional of β-CD slightly increased …

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Development Of Mucoadhesive Biloniosome Nanoparticles For Enhanced Gastrointestinal Absorption Of Cordycepin, Warut Kengkittipat Jan 2019

Development Of Mucoadhesive Biloniosome Nanoparticles For Enhanced Gastrointestinal Absorption Of Cordycepin, Warut Kengkittipat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cordycepin, an adenosine analogue, has displayed numerous pharmacological and therapeutic implications including enhanced apoptosis and inhibition of proliferation of cancer cells, antioxidant property and improving sexual activity. However, oral administration of cordycepin has limited practical use due to its poor bioavailability in the intestine. Here, we developed a novel hybrid nanoparticle system for effective delivery of cordycepin in the gastrointestinal tract by using the bile salt-based liposome/niosome hybrid system (designated as biloniosome). In addition, mucoadhesive chitosan biopolymer was coated on the biloniosome nanoparticles to improve the mucoadhesive properties thereby enhancing the drug efficiency. Cordycepin-encapsulated biloniosome nanoparticles were synthesized by solvent …

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Expression Of Human Dentin Matrix Protein 1 In Escherichia Coli And Nicotiana Benthamiana And Their Effect On Proliferation And Osteogenic Differentiation Of Human Periodontal Ligament Stem Cells, Aktsar Roskiana Ahmad Jan 2019

Expression Of Human Dentin Matrix Protein 1 In Escherichia Coli And Nicotiana Benthamiana And Their Effect On Proliferation And Osteogenic Differentiation Of Human Periodontal Ligament Stem Cells, Aktsar Roskiana Ahmad

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aimed to express recombinant protein human Dentin Matrix Protein 1 (hDMP1) in Escherichia coli and Nicotiana benthamiana and investigated the osteogenic differentiation effects in human Periodontal Ligament Stem Cells (hPDLSCs). The gene encoding hDMP1 was ligated into the pET22b and pBY2R2e expression vectors. Recombinant hDMP1 protein has been productively expressed in E. coli and N. benthamiana. E. coli-produced hDMP1 resulted in 60 kDa and 100, and the optimal condition to produce highly expression was demonstrated at 0.5 mM IPTG and incubation at 37oC for 6 hr. N. benthamiana-produced hDMP1 protein showed in a 100 kDa that indicated the …

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Inhibitory Effects Of Compounds Isolated From Ethyl Acetate Extracts Of Glycosmis Parva Branches And Leaves On Lps-Induced Raw 264.7 Macrophage Activation, Chanyanuch Laprasert Jan 2019

Inhibitory Effects Of Compounds Isolated From Ethyl Acetate Extracts Of Glycosmis Parva Branches And Leaves On Lps-Induced Raw 264.7 Macrophage Activation, Chanyanuch Laprasert

Chulalongkorn University Theses and Dissertations (Chula ETD)

Macrophages play major roles to produce several inflammatory mediators in many chronic inflammatory diseases. Current anti-inflammatory drugs target these mediators to alleviate inflammation symptoms. Searching for new anti-inflammatory agents is always needed due to problems from currently used anti-inflammatory drugs. This study aimed to investigate the anti-inflammatory potential of three main compounds, arborinine, N-methylatalaphylline and S-deoxydihydroglyparvin (DDGP), isolated from Glycosmis parva leaves and branches on lipopolysaccharide (LPS)-activated macrophage RAW 264.7 cells. Only DDGP demonstrated a potent inhibitor of LPS-activated macrophages. It inhibited expression of inducible nitric oxide synthase and decreased nitric oxide production with IC50 3.47 ± 0.1 µM. It …

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การวินิจฉัยโรคจากภาพอัลตร้าซาวด์ของก้อนในตับโดยเทคนิค Convolutional Neural Network, ยิ่งลักษณ์ ศรีธัญรัตน์ Jan 2019

การวินิจฉัยโรคจากภาพอัลตร้าซาวด์ของก้อนในตับโดยเทคนิค Convolutional Neural Network, ยิ่งลักษณ์ ศรีธัญรัตน์

Chulalongkorn University Theses and Dissertations (Chula ETD)

วัตถุประสงค์: เพื่อศึกษาการทำงานของ Convolutional Neural Network (CNN) ในการตรวจหาและวินิจฉัยโรคจากภาพอัลตร้าซาวด์ของก้อนในตับในเวชปฏิบัติ โดยผ่านตัวชี้วัดได้แก่ ความไว (sensitivity), ความจำเพาะ (specificity) และ ความถูกต้อง (accuracy) วิธีการศึกษา: เก็บภาพอัลตร้าซาวด์ตับในผู้ป่วยที่มีความเสี่ยงต่อการเกิดมะเร็งตับปฐมภูมิที่มารับการตรวจรักษาคลินิกโรคตับ โรงพยาบาลจุฬาลงกรณ์ ในช่วง 8 เดือน โดยใช้เครื่องอัลตร้าซาวด์ 4 เครื่อง บันทึกข้อมูลก้อนในตับและพื้นหลังที่เป็นเนื้อตับ จากนั้นทำการลงผลการวินิจฉัยสุดท้ายของก้อนที่ตับ อ้างอิงจากผลเอกซเรย์คอมพิวเตอร์ เอกซเรย์คลื่นแม่เหล็กไฟฟ้า หรือ การเจาะ/ตัดก้อนที่ตับมาตรวจทางพยาธิวิทยา หลังจากนั้นนำภาพก้อนในตับที่รวบรวมได้ไปทดสอบการทำงานของ CNN ผลการศึกษา: ผู้ป่วยที่ตรวจพบก้อนในตับทั้งหมด 156 คน เป็นผู้ป่วยตับแข็ง 79 คน และไม่เป็นตับแข็ง 77 คน ภาพก้อนในตับทั้งหมด 569 lesions แบ่งเป็น HCC 138 lesions, cyst 177 lesions, hemangioma 113 lesions, focal fat infiltration (FFI) 47 lesions และ focal fat sparing (FFS) 94 lesions อัตราการตรวจพบก้อนในตับของ CNN เท่ากับร้อยละ 52 โดยอัตราการตรวจพบก้อนในตับในกลุ่มที่เป็นตับแข็งสูงกว่าในกลุ่มที่ไม่เป็นตับแข็งอย่างมีนัยสำคัญ คือร้อยละ 61 เทียบกับร้อยละ 45 (p= 0.0002) การวินิจฉัยชนิดของก้อนในตับพบว่า CNN มีความไวร้อยละ 87, ความจำเพาะร้อยละ 97 และ ความถูกต้องร้อยละ 95 สรุปผล: CNN สามารถวินิจฉัยชนิดของก้อนในตับที่พบบ่อยได้เป็นอย่างดี โดยพื้นหลังของเนื้อตับไม่ส่งผลต่อการวินิจฉัยชนิดของก้อนในตับ

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Pelletization Of Nickel Catalyst For Hydrogen Production From Glycerol Steam Reforming, Jinnawat Saengsawang Jan 2019

Pelletization Of Nickel Catalyst For Hydrogen Production From Glycerol Steam Reforming, Jinnawat Saengsawang

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work investigated the pelletization of Ni/Al2O3 catalyst for hydrogen production from glycerol steam reforming (GSR). Effects of preparation methods, binders, and pellet shapes (cylindrical/spherical) on the catalyst's physicochemical properties and catalytic performance in a fixed-bed reactor were considered. Freshly prepared catalyst was characterized with XRD, N2 adsorption-desorption, SEM/EDX, H2-TPR, and H2-chemisorption. The crushing strength of the catalyst pellets was also evaluated by a hydraulic press. GSR was carried out at a water to glycerol molar ratio of 9: 1, a total liquid flow rate of 0.04 ml/min, 600 ºC, and 1 atm. Ni/Al2O3 catalyst pellets showed superior catalytic performance …

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Bacterial Cellulose/Alginate/Gelatin Composite Films For Wound Dressing, Nadda Chiaoprakobkij Jan 2019

Bacterial Cellulose/Alginate/Gelatin Composite Films For Wound Dressing, Nadda Chiaoprakobkij

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aimed to develop the blended bacterial cellulose (BC)/ alginate (A)/ gelatin (G) incorporating with curcumin (C) for wound dressing application. Fourier transform infrared (FT-IR) spectroscopy showed that the interaction among bacterial cellulose/alginate/gelatin curcumin molecules were only physical but not chemical intermolecular level. Water vapor and oxygen permeabilities of the fabricated films were close to commercially avaialbe wound dressings. Curcumin incorporation lowered fluid absorption ability, water vapor and oxygen permeabilities. In vitro culture of human keratinocytes, and human gingival fibroblasts evidenced that the fabricated composite films could promote cell proliferation. Curcumin-loaded films showed anticancer activity against human oral cancer …

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Reinforcing Natural Rubber Latex Foam With Nano And Micro Cellulose Fibers Via Dunlop Method, Sirilak Phomrak Jan 2019

Reinforcing Natural Rubber Latex Foam With Nano And Micro Cellulose Fibers Via Dunlop Method, Sirilak Phomrak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Natural rubber latex foam (NRLF) was reinforced with micro- and nano-cellulose at a loading content of 5-20 parts per hundred of rubber (phr) via the Dunlop process. Cellulose powder from eucalyptus pulp and bacterial cellulose (BC) was used as a microcellulose (MC) and nanocellulose (NC) reinforcing agent, respectively. NRLF, NRLF-MC, and NRLF-NC exhibited interconnected macroporous structures with a high porosity and a low-density. The forms contained pores with sizes in a range of 10-500 µm. As compared to MC, NC had a better dispersion inside the NRLF matrix and showed a higher adhesion to the NRLF matrix, resulting in a …

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Prediction Of Catalyst Bed Density And Simulation Of Glycerol Steam Reformer For Hydrogen Production, Vorathorn Charoensuk Jan 2019

Prediction Of Catalyst Bed Density And Simulation Of Glycerol Steam Reformer For Hydrogen Production, Vorathorn Charoensuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

A simple method was proposed to generate a rigid model and to predict the packing density of catalyst using Blender software. It is a free and open-source 3D creation suite animating catalyst pellets freely falling into a container. The effects of different catalyst shapes (sphere and cylinder) and sizes (2–5 mm) on the packing density of catalyst bed were investigated. It was found that the void fraction decreased with decreasing catalyst pellet diameter for all reactor diameters (18-50 mm). Moreover, the void fraction decreased with increasing reactor size for all catalyst shapes and sizes. The results also showed that the …

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Development Of Spray Dried Encapsulated Curcumin Powder As Functional Food Ingredient, Alwani Hamad Jan 2019

Development Of Spray Dried Encapsulated Curcumin Powder As Functional Food Ingredient, Alwani Hamad

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study investigated the development of the spray-dried encapsulated curcumin powder from an oil-water-emulsion with better functional properties and evaluated its stability characters during storage and reconstitution. This research was conducted in four parts. The first part was the selection and optimization of curcumin solubility in edible oil. It was found that MCT oil was the best carrier oil with curcumin solubility of 17.01 mg/mL, which was achieved by heating at 80oC for 10 min. The curcumin solubility in MCT oil was further applied to nanoemulsion and conventional emulsion, in which the conventional one showed shorter stability...

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Effects Of Hydrogen Synthesis Inhibition On Changes Of Bioproduct Contents In Cyanobacterium Synechocystis Sp. Pcc 6803, Nannaphat Sukkasam Jan 2019

Effects Of Hydrogen Synthesis Inhibition On Changes Of Bioproduct Contents In Cyanobacterium Synechocystis Sp. Pcc 6803, Nannaphat Sukkasam

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cyanobacteria have an ability to convert carbon dioxide and solar light to bioproducts. Synechocystis sp. PCC 6803 is the laboratory model strain of cyanobacteria with known metabolism and biochemistry. NADPH is one of the essential electron carriers and coenzymes required for various cellular metabolism including the production of bioproducts. [NiFe]-Hydrogenase consumes NADPH to produce hydrogen gas which considerably the loss of metabolic energy. Thus, the elimination of [NiFe]-hydrogenase would increase NADPH level in the cell and might increase the accumulation of bioproducts. In this work, hoxY and hoxH genes (encoding the two catalysis subunits of [NiFe]-hydrogenase) were inactivated. The inactivation …

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