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Simulation Model For Outbound Logistics In Quarry Business, Chanyakan Chawaranggoon Jan 2018

Simulation Model For Outbound Logistics In Quarry Business, Chanyakan Chawaranggoon

Chulalongkorn University Theses and Dissertations (Chula ETD)

The study of outbound logistics is part of quarrying process where final products are being served to customers. It includes all activities begins from when a truck entering weight station to when the truck leaves the system after a final weighing. An increasing of customer demands within limited serving space and limited resources cause a higher total flow time customer spent in the system which also leads to longer queues. The study aims to simulate a current outbound logistics for a quarry business using ARENA simulation model and analyze truck queueing and loader scheduling policy that help reduce total flow …


Improving Raw Materials Warehouse Utilization And Efficiency In A Haircare Manufacturer, Chariya Paveenchana Jan 2018

Improving Raw Materials Warehouse Utilization And Efficiency In A Haircare Manufacturer, Chariya Paveenchana

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study aims to improve the capacity, efficiency, and utilization of raw materials warehouse in a case study of haircare manufacturer in Thailand. At the same time, it is our goal to save the storage cost of finished products at the external public warehouse by locating some of the finished products at this internal raw materials warehouse. The key methodologies used to improve the current raw materials warehouse are removing obsolete materials from the warehouse, regrouping materials according to types, sizes, and turnover rates, reallocating space for each group of materials, considering beam height adjustment, and reassigning the location for …


Defect Reduction In Manufacturing Process Of In-Mold Decoration Of Injection Molded Components, Jintra Supapan Jan 2018

Defect Reduction In Manufacturing Process Of In-Mold Decoration Of Injection Molded Components, Jintra Supapan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purpose of this research is to reduce the defect rate from manufacturing process of in-mould decoration (IMD), a process combining PET film with decorative patterns are moulded together with ABS resins, which has been developed to reduce the secondary process of decorative screen printing. Recently, the case study company has produced components with a high defect rate average 11.43% in Feb-Jun 2018, which increased sharply to 22.3% in June 2018. The major causes of the defect resulting from PET film peeled off and difficult to assembly. In order to reduce the defect rate, the five steps of the DMAIC …


Development Of An International Curriculum Model In Education Management For Vietnam Higher Education Institutions, Thi My Ngoc Nguyen Jan 2018

Development Of An International Curriculum Model In Education Management For Vietnam Higher Education Institutions, Thi My Ngoc Nguyen

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purposes of this research are (1) to investigate the current state and the need for internationalization of curriculum of Master Degree in Education Management for Vietnam higher education institutions (2) to analyze good practices for the internationalization of curriculum of Master Degree in Education Management in international universities, (3) to develop an international curriculum management model for Vietnam higher education institutions. The samples include (1) seven policy makers at national and institutional level (2) five administrators at faculty level (3) 67 faculty members, and (4) 217 students from five Vietnamese higher education institutions offering Master Degree in Education Management. …


Periodic-Review Order Policy For A Two-Echelon Inventory Problem With Seasonal Demand, Noppadon Sakulsom Jan 2018

Periodic-Review Order Policy For A Two-Echelon Inventory Problem With Seasonal Demand, Noppadon Sakulsom

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation presents methodologies to determine ordering policies for a 2-echelon inventory system with multiple replenishing modes under seasonal demand. The system operates on periodic review basis using reorder point and order-up-to point or (R,s,S). An Echelon stock concept is applied where each location makes decisions on its own inventory information and the information of all locations downstream. We decompose a problem into two phases and propose a methodology based on mixed-integer programming models to determine ordering policies for a system with one replenishing mode. Then, another methodology based on the genetic algorithm and binary search is developed to solve …


Forecasting International Tourist Arrivals From Major Countries To Thailand, Ontheera Hwandee Jan 2018

Forecasting International Tourist Arrivals From Major Countries To Thailand, Ontheera Hwandee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Tourism industry is one of industries that are very important for Thai economy. In order to achieve effective marketing and resource planning, accurate forecasting of tourist arrivals from major countries to Thailand is necessary for Thai tourism industry. In this paper, various forecasting models are explored to forecast monthly tourist arrivals from China, Malaysia, Korea, Japan, Russia, UK and US. The proposed models include both time series models, i.e., SARIMA, Holt-Winter, and explanatory models, i.e., Multiple Regression and Feed Forward Artificial Neural Networks (FANNs). Economic factors such as income, relative price, exchange rates, and dummy variables of seasonality and news …


Forecasting Hotel Daily Occupancy For High-Frequency And Complex Seasonality Data, Phoom Ungtrakul Jan 2018

Forecasting Hotel Daily Occupancy For High-Frequency And Complex Seasonality Data, Phoom Ungtrakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Accurate hotel daily occupancy forecasting is an important input for hotel revenue management. This research presents forecasting models both time series and causal methods for a case study 4-star hotel in Phuket, Thailand. Holt-Winters, Box-Jenkins, Box-Cox transformation, ARMA errors, trend and multiple seasonal patterns (BATS), Trigonometric BATS (TBATS), back-propagation Neural Network (BPNN), and Support Vector Regression (SVR) are explored in this work, where Same Day Last Year is considered as benchmark forecast. For causal method, independent variables used as regressor inputs are transformed data observed in the past periods, the number of tourist arrivals from main countries to Phuket, Oil …


Steady-State Determination Of Continuous Powder Mixing By Near Infrared Spectroscopy As Process Analytical Technology, Katesaraporn Wongves Jan 2018

Steady-State Determination Of Continuous Powder Mixing By Near Infrared Spectroscopy As Process Analytical Technology, Katesaraporn Wongves

Chulalongkorn University Theses and Dissertations (Chula ETD)

Powder mixing is one of an important unit operation in pharmaceutical manufacturing of solid dosage forms. Continuous mixing was developed as an alternative method to reduce disadvantages of traditional batch mixing processes. This process was originally developed using horizontal cylindrical mixer equipped with Process Analytical Technology (PAT) tools for real-time monitoring. In the present study, a vertical cylindrical mixer was developed and evaluated. Near Infrared (NIR) spectra obtained by monitoring the mixing process were pretreated with Multiplicative Scatter Correction (MSC), second derivative treatment and Norris-William smoothing in the 6800 - 8700 cm-1 range before a calibration model using PLS was …


Cyclic Clique Decompositions Of Powerof Cycles, Apiwat Peereeyaphat Jan 2018

Cyclic Clique Decompositions Of Powerof Cycles, Apiwat Peereeyaphat

Chulalongkorn University Theses and Dissertations (Chula ETD)

A clique decomposition P of a graph G is a collection of cliques of G such that each edge of G belongs to exactly one clique in the collection. We say that P is cyclic if there is an isomorphism : V (G)→ V (G) such that Kk{α (v₁), α (v₂), α (v₃), ... , α (vk)g is a clique in P whenever Kk{v₁; v₂; v₃; :::; vk} is. The k-power of an n-cycle, Ck n, is the graph having the same vertex set as Cn and uv is an edge in Ck n if and only if dCn(u; v) …


Defective Colorings On Complete Bipartite And Multipartite K-Uniform Hypergraphs, Artchariya Muaengwaeng Jan 2018

Defective Colorings On Complete Bipartite And Multipartite K-Uniform Hypergraphs, Artchariya Muaengwaeng

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we modify the definition of a defective coloring and a defective chromatic number on graphs to a defective coloring and a defective chromatic number on hypergraphs. First, we find the defective chromatic number on a complete bipartite k-uniform hypergraph and the defective chromatic number on a complete bipartite k-uniform hypergraph of which each color class is acyclic. Second, we determine the defective chromatic number and the defective chromatic number of which each color class is acyclic on a complete k-partite k-uniform hypergraph whose each edge has k vertices from k different partite sets. Finally, we determine the …


Critical Exponent For Nonlinear Nonlocal Equations, Auttawich Manui Jan 2018

Critical Exponent For Nonlinear Nonlocal Equations, Auttawich Manui

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we study the nonlinear nonlocal equation ∂t u=J*u-u+u¹+p where p>0 and J is nonnegative, bounded, and radially symmetric with unit integral. The Fourier transform of J satisfies J ̂(ξ)=1-A|ξ|^β (ln1/|ξ| 〗 )^μ+o(〖|ξ|〗^β (ln〖1/(|ξ|)〗 )^μ ) as ξ→0, for 0<β≤2, μ∈R, and A>0. In this study, we establish the local existence, uniqueness, and the comparison principle of solutions. Furthermore, we show that the Fujita critical exponent for this equation is β/n when μ<0. For the case μ>1, we discover that the critical exponent is β/n , and the solutions belong to the global to the small initial data regime.


Streaming Data Classification Method Using Scalable Hyper-Ellipsoids With Linear Discriminant Projection Distance Ratio, Perasut Rungcharassang Jan 2018

Streaming Data Classification Method Using Scalable Hyper-Ellipsoids With Linear Discriminant Projection Distance Ratio, Perasut Rungcharassang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Learning streaming data with limited size of memory storage becomes an interesting problem. Although there have been several learning methods recently proposed, based on the interesting concept of discard-after-learn, the performance of these issues: the learning speed, number of redundant neurons, and classification accuracy of these methods can be further improved in terms of faster speed, less number of neurons, and higher accuracy. The following new four concepts and approaches were proposed in this dissertation: (1) a more generic structure of hyper-ellipsoidal function called Scalable Hyper-Ellipsoidal Function (SHEF) capable of handling the problem of curse of dimensionality by introducing a …


Generalized Symplectic Graphs And Generalized Orthogonal Graphs Over Finite Commutative Rings, Siripong Sirisuk Jan 2018

Generalized Symplectic Graphs And Generalized Orthogonal Graphs Over Finite Commutative Rings, Siripong Sirisuk

Chulalongkorn University Theses and Dissertations (Chula ETD)

Let R be a finite commutative ring with identity, n ∈ N and β a bilinear form on Rⁿ. In this dissertation, we count the numbers of free submodules and totally isotropic free submodules of Rⁿ of rank s by using the lifting idea. We define the generalized bilinear form graph whose vertex set is the set of totally isotropic free submodules of Rⁿ of rank s and the adjacency condition is given by some rank conditions. We study this graph when (Rⁿ, β) is a symplectic space and an orthogonal space. We can determine the degree of each vertex …


Variant Of D'Alembert Functional Equation On Compact Homogeneous Space, Sorawit Viwanthananut Jan 2018

Variant Of D'Alembert Functional Equation On Compact Homogeneous Space, Sorawit Viwanthananut

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this work, we introduce a new functional equation on compact homogeneous spaces based on the d'Alembert functional equation on compact groups. We solve the functional equation by using tools from harmonic analysis.


A Numerical Investigation Of Augmented Heat Transfer In Rectangular Ducts With Ribs, Warissara Tangyotkhajorn Jan 2018

A Numerical Investigation Of Augmented Heat Transfer In Rectangular Ducts With Ribs, Warissara Tangyotkhajorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

The application of roughness structure of ribs inside a smooth channel is one effective way of heat transfer augmentation, but the accompanied pressure drop could be high. A novel V-rib design with branches was introduced and numerical simulations on the thermo-fluid impact of heat transfer and pressure drop were investigated. The parameters of investigation include the branching number and the pitch ratio of the V-ribs. It appears that increasing the relative pitch ratio serves to improve the overall performance of a roughened channel. The effect of the branching number is only experienced at low pitch ratio. At high pitch ratio, …


The Pharmacokinetic Model Of 18f-Fdopa In Pet Brain Imaging For Early Parkinson’S Disease, Wirunpatch Buratachwatanasiri Jan 2018

The Pharmacokinetic Model Of 18f-Fdopa In Pet Brain Imaging For Early Parkinson’S Disease, Wirunpatch Buratachwatanasiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

Parkinson’s disease (PD) symptom usually appears when over half of all dopaminergic neurons have died. Early detection and treatment approach are; therefore, very important. The 18F-FDOPA PET scan is extensively examined to differentiate the normal and pathological dopamine metabolism in the human brain. The purpose of this study was to investigate the transfer rate constants of 18F-FDOPA in PET brain imaging based on compartmental model in early Parkinson’s disease. The retrospective data from five early PD patients who underwent 18F-FDOPA PET brain scan at King Chulalongkorn Memorial Hospital (KCMH) were collected. After 18F-FDOPA was administered intravenously, PET images were acquired …


Comparative Study Between Vitamin B 1-6-12 And Vitamin B 12 For Neurosensory Recovery After Bilateral Sagittal Split Ramus Osteotomy, Worawee Trising Jan 2018

Comparative Study Between Vitamin B 1-6-12 And Vitamin B 12 For Neurosensory Recovery After Bilateral Sagittal Split Ramus Osteotomy, Worawee Trising

Chulalongkorn University Theses and Dissertations (Chula ETD)

A major complication from Bilateral Sagittal Split Ramus Osteotomy (BSSRO) is inferior alveolar nerve injured that manifest as neurosensory disturbance (NSD) on the lower lip, chin. Although the NSD is not a life-threatening problem but it impacts the patient's daily life. Vitamin B is commonly used to treat peripheral neuropathy but it is only few study for NSD from BSSRO. The aim of this study was to evaluate the effect of oral vitamin B1-6-12 and vitamin B12 on NSD after BSSRO. The study design was as a randomized, single blinded control trial of 75 patients who were NSD from BSSRO …


Polyisocyanurate Foams Preparation Catalyzed By Mixtures Of Copper-Amine Complexes/Potassium 2-Ethylhexanoate, Teeraporn Suwannawet Jan 2018

Polyisocyanurate Foams Preparation Catalyzed By Mixtures Of Copper-Amine Complexes/Potassium 2-Ethylhexanoate, Teeraporn Suwannawet

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, a new catalyst system for the preparation of polyisocyanurate (PIR) foam was developed. The mixture of copper-amine complex:potassium 2-ethylhexanoate (K-15) and metal-ethanolamine complex:K-15 were used as catalysts. Two copper-amine complexes and two metal-ethanolamine complexes, namely Cu(OAc)2(en)2, Cu(OAc)2(trien), Cu(OAc)2(EA)2 and Zn(OAc)2(EA)2, respectively; where en = ethylene diamine, trien = triethylenetetramine and EA = ethanolamine, were used as catalyst for blowing and gelling reactions. K-15 was used as a catalyst for trimerization reaction. These catalysts could be further used in the preparation of PIR forms without purification. Characterization of catalysts were done by using UV-visible spectroscopy. The factors investigated …


Improved Barrier Properties Of Pp/Ldpe Composite Film: Effect Of Montmorillonite And Poly (Lactic Acid), Supornpat Mooninta Jan 2018

Improved Barrier Properties Of Pp/Ldpe Composite Film: Effect Of Montmorillonite And Poly (Lactic Acid), Supornpat Mooninta

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, the properties of polypropylene (PP) were improved for single layer film application by incorporating low density polyethylene (LDPE), poly(lactic acid) (PLA) and montmorillonite (MMT). The polymer composites was prepared by melt blending using a twin screw extruder and the film was produced by cast film extruder. The addition of LDPE in PP improved the elongation at break and tear strength. The PP/LDPE blend at the ratio of 80:20 (w/w) was selected for blending with PLA and MMT and the PP/LDPE/PLA/MMT composite showed the increased tensile modulus while the elongation at break decreased with increasing PLA and MMT …


Surface-Enhanced Raman Scattering Technique For Polycyclic Aromatic Hydrocarbons Detection Using Thiol-Functionalized Silver Nanoparticle Films, Sathita Taksadej Jan 2018

Surface-Enhanced Raman Scattering Technique For Polycyclic Aromatic Hydrocarbons Detection Using Thiol-Functionalized Silver Nanoparticle Films, Sathita Taksadej

Chulalongkorn University Theses and Dissertations (Chula ETD)

The detection of polycyclic aromatic hydrocarbons (PAHs) is developed based on surface-enhanced Raman scattering (SERS) using silver nanoparticle films as SERS substrates. The films are fabricated by a Langmuir Blodgett (LB) method and the surface of AgNP films are functionalized with various types of aromatic and aliphatic thiols, i.e., naphthalenethiol, phenylethanethiol, pentanethiol, octanethiol, and dodecanethiol, to create a hydrophobic layer for PAHs to attach on and stay in hot spot. The results indicate that nine kinds of PAHs with different structures, i.e., anthracene, chrysene, naphthacene, naphthalene, phenanthrene, pentacene, perylene, pyrene, and triphenylene, can attach on the surfaces of thiol-modified AgNP …


Preparation And Characterization Of Starch Films Reinforced With Citrate Cellulose Nanocrystals, Prapaporn Nakarat Jan 2018

Preparation And Characterization Of Starch Films Reinforced With Citrate Cellulose Nanocrystals, Prapaporn Nakarat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Citrate-modified bacterial cellulose nanocrystals (citrate CNCs) were prepared by a green one-pot dual acid (citric and hydrochloric acids) method and used them to reinforce three types of starch films; corn, wheat and rice starch films. The average length and width of citrate CNCs were 583 and 46 nm, respectively. The degree of citrate substitution on CNCs was 0.075 and its crystallinity index was closely to the original bacterial cellulose. The effect of various amount of citrate CNCs (0-20%wt of starch) on film property was study. Three starch films showed the same trend of examination results. The film thickness of most …


Preparation Of Alginate Capsule Using Two Coaxial Glass-Tube, Panida Watchanung Jan 2018

Preparation Of Alginate Capsule Using Two Coaxial Glass-Tube, Panida Watchanung

Chulalongkorn University Theses and Dissertations (Chula ETD)

TEMPO-Oxidized bacterial cellulose (TOBC) were obtained using TEMPO-mediated oxidation (TOBC) to produce carboxylate groups on bacterial cellulose surfaces. TOBC had lower crystallinity but better aqueous dispersion than bacterial cellulose. TOBC was used as a reinforcement agent for production alginate capsules. The alginate capsules for entrapping rice bran oil were made via a coaxial-glass tube. The factors that influenced on the shape and production efficiency of capsules were the gap between tube tip and the Ca2+ ions bath and the viscosity of shell solution. However, these factors had no effect on the size and shell thickness of capsules. Increasing of TOBC …


Sustained Release Of Antibiotics From Bone Spacer, Miranda Oungeun Jan 2018

Sustained Release Of Antibiotics From Bone Spacer, Miranda Oungeun

Chulalongkorn University Theses and Dissertations (Chula ETD)

Bone spacer is a device developed to temporarily insert into the body to treat infected tissue caused by bone replacement. Burst release and short-time release of antibiotics from bone spacer not only limits their ability to clear infection but also causes tissue inflammation. Therefore, here we have fabricated bone spacers containing antibiotic-loaded particles, studied their antibiotic release character, and measured the compressive strength of PMMA cements. Four biocompatible particles were investigated. Vancomycin and erythromycin were used as hydrophilic and hydrophobic model drugs, respectively. Rice granules and calcium citrate particles were loaded with vancomycin and gave the percent loading of 84.9 …


Energy And Exergy Analysis For Cryogenic Process Design/Retrofit, Nattawat Threerachannarong Jan 2018

Energy And Exergy Analysis For Cryogenic Process Design/Retrofit, Nattawat Threerachannarong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Energy and Exergy analysis are one of alternative techniques to analyze chemical processes in term of energy quality parameters such as enthalpy, entropy and exergetic temperature. The exergetic temperature can conduct Exergy Composite Curves diagram (ECCs) (Marmolejo-Correa, 2012) which represents exergy targets: exergy requirement, exergy rejection and exergy destruction etc. In addition, these targets can be used for improving processes. The strength points of these analysis are to design the new process and to improve the utility performance. Therefore, these analysis methods have been applied to low-temperature process that requires a large amount of energy consumption. In this work, there …


Heat Exchanger Network Design/Retrofit With Partitioning Technique For Linearization Of Specific Heat Capacity-Temperature Relation, Siwat Valeekiatkul Jan 2018

Heat Exchanger Network Design/Retrofit With Partitioning Technique For Linearization Of Specific Heat Capacity-Temperature Relation, Siwat Valeekiatkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Heat Exchanger Network (HEN) design has been studied for 40 years starting from heuristic technique; pinch analysis and design method to mathematical programming. The stage-wise superstructure by mathematical programming from Yee and Grossmann (1990) was one of the famous models suitable for industrial HEN design under assumption of constant average specific heat capacity (Cp) which generally should be fitted by empirical form of cubic equation. Zhu and Asante (1999) and Ayotte-Sauvé et al. (2017) used piece-wise linearization called stream segment model, to approximate Cp. Their Cp approximation techniques used high number of piece-wises to calculate Cp accurately. This paper presents …


Effect Of Cu(In,Ga)₃Se₅ Ultra-Thin Layer On Optical Properties And Photovoltaic Efficiency Of Cu(In,Ga)Se₂ Thin Film Solar Cells, Boonyaluk Namnuan Jan 2018

Effect Of Cu(In,Ga)₃Se₅ Ultra-Thin Layer On Optical Properties And Photovoltaic Efficiency Of Cu(In,Ga)Se₂ Thin Film Solar Cells, Boonyaluk Namnuan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cu(In,Ga)3Se5 (135-CIGS) layers with various thicknesses were deposited on the surface of ~1.8 micron thick Cu(In,Ga)Se2 (112-CIGS) photon absorber in the fabrication of CIGS thin film solar cells. This significantly affects the shift of the optical band gap energy from 1.15 eV (112-CIGS) to 1.19 eV, with only 10 nm thick of 135-CIGS capping layer, leading to the increase in the open-circuit voltage (Voc) of the solar cells. The optical transmission spectra show no sign of separated 135-CIGS layer. The maximum Voc of 670 mV is obtained from 5-10 nm thick 135-CIGS capping layer on 112-CIGS compared to 646 mV …


Application Of Adversarial Networks In Search For Four Top Quark Production In Cms, Vichayanun Wachirapusitanand Jan 2018

Application Of Adversarial Networks In Search For Four Top Quark Production In Cms, Vichayanun Wachirapusitanand

Chulalongkorn University Theses and Dissertations (Chula ETD)

One burden of high energy physics data analysis is uncertainty within the measurement, both systematically and statistically. Even with sophisticated neural network techniques that are used to assist in high energy physics measurements, the resulting measurement may suffer from both types of uncertainties. Fortunately, most types of systematic uncertainties are based on knowledge from information such as theoretical assumptions, for which the range and behaviour are known. It has been proposed to mitigate such systematic uncertainties by using a new type of neural network called adversarial neural network (ANN) that would make the discriminator less sensitive to these uncertainties, but …


Effects Of Organic Molecule Orientations On Perovskite Structure Of Formamidinium Lead Iodide, Wiwittawin Sukmas Jan 2018

Effects Of Organic Molecule Orientations On Perovskite Structure Of Formamidinium Lead Iodide, Wiwittawin Sukmas

Chulalongkorn University Theses and Dissertations (Chula ETD)

Latterly, an emergence of the hybrid organic-inorganic perovskites has captivated an increasing rate of world-wide attention due to their approving physical properties. Formamidinium lead iodide (FAPI), a promising compound owing to its high photovoltaic performance, consists of an organic molecule, i.e. the formamidinium (FA) cation, dwelling in the centre of the cubic unit cell, caged by the inorganic framework, PbI6. By adopting the ab initio method based on the density functional theory including the spin-orbit coupling (SOC) effects, the effects of the FA cation on the cubic FAPI were thoroughly and systematically investigated. Solidly armed with Euler's rotations, energy landscapes …


Effect Of Local Rewiring In Adaptive Epidemic Erdos-Renyi Random Networks, Suwakan Piankoranee Jan 2018

Effect Of Local Rewiring In Adaptive Epidemic Erdos-Renyi Random Networks, Suwakan Piankoranee

Chulalongkorn University Theses and Dissertations (Chula ETD)

Adaptive epidemic network is driven by two main processes, (1) infectionrecovery process that changes the states of the nodes, and (2) rewiring process that modifies the topology of the network. In the past two decades, epidemic models on adaptive networks have gained interests because understanding the dynamics between these two processes can be key to improving control of diseases. However, in most of these models, the rewiring mechanism is based on information known globally, i.e., everyone knows the health status of all others in the network. This concept is not practical in real life for large network. This dissertation aims …


Delay In Health Seeking Behavior Among Tb Patients In Chiang Rai Province, Thailand, Yotsanon Sikkhajan Jan 2018

Delay In Health Seeking Behavior Among Tb Patients In Chiang Rai Province, Thailand, Yotsanon Sikkhajan

Chulalongkorn University Theses and Dissertations (Chula ETD)

The aim of this study was to determine the pattern of health seeking behavior and factors associated with delay in health seeking behavior among tuberculosis patients in border hospitals, Chiang Rai province, Thailand. A cross-sectional study was conducted in four biggest border hospitals in Chiang Rai province, Thailand during May to July 2018 among 103 identified tuberculosis cases. Data was collected by a structured questionnaire on patients' general characteristics, HIV status, distance from health service, health seeking treatment with onset symptoms, and patient delay. Collected data was analyzed in SPSS 22. Both descriptive and inferential statistics was employed in data …