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Articles 1351 - 1380 of 6471
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Effect Of Ch4 Impurity On Ethanol-Assisted Methanol Synthesis From Co2 And H2 Over Cu/Zn0 Catalyst, Banthita Woraphan
Effect Of Ch4 Impurity On Ethanol-Assisted Methanol Synthesis From Co2 And H2 Over Cu/Zn0 Catalyst, Banthita Woraphan
Chulalongkorn University Theses and Dissertations (Chula ETD)
The problem of CO2 emissions into the atmosphere is an issue that needs to be addressed worldwide. One of the ways to tackle this problem is to bring back CO2 and reuse it to produce higher-valued products like methanol. Nevertheless, exhausted gases emitted from many industries contain not only CO2 but also various impurities, of which CH4 is a common one. In this work, the simulated flue gas containing CH4 impurity was studied to examine its effect as the feed on the methanol production over Cu/ZnO catalyst, in the presence of ethanol as the catalytic solvent to enhance the conversion …
Evaluation Of Root And Canal Morphology Of Mandibular First Permanent Molars In A Selected Thai Population Using Cone-Beam Computed Tomography, Pitcha Suwannasin
Evaluation Of Root And Canal Morphology Of Mandibular First Permanent Molars In A Selected Thai Population Using Cone-Beam Computed Tomography, Pitcha Suwannasin
Chulalongkorn University Theses and Dissertations (Chula ETD)
The aim of current study was to investigate numbers of root canal, canal configurations, canal curvatures and pulp chamber of the mandibular first molars using cone-beam computed tomography (CBCT) images in a selected Thai population. Total of 492 mandibular first molars were evaluated. The number of roots, root canals and their root canal configurations were recorded. When c-shaped molars were excluded, 479 teeth were further investigated the number and direction of root canal curvature, also morphological of pulp chamber. Correlations with gender, tooth side and age (for pulp chamber) were analyzed. This current study found that the prevalence of teeth …
Wear Resistance And Surface Roughness Of Injectable Resin Composites After Chewing Simulation, Napat Lapaschaone
Wear Resistance And Surface Roughness Of Injectable Resin Composites After Chewing Simulation, Napat Lapaschaone
Chulalongkorn University Theses and Dissertations (Chula ETD)
The purpose of this study was to evaluate wear resistance and surface roughness of injectable resin composites after undergoing chewing simulation and compared with those of conventional flowable resin composites and conventional paste resin composites. Ten specimens of each product from three different types: 1) two injectable resin composites (GU, BI), 2) two conventional flowable resin composites (SF, BF) and 3) two conventional paste resin composite (GP,BT), were fabricated in a sample holder and top surface was polished using silicon carbide papers. The surface topography of the specimens was profiled using three-dimensional contact profilometer before subjected to chewing simulation at …
Fracture Strength Of Restored Tunnel Preparation With Various Heights Of Marginal Ridge, Phirinat Aurpanchasin
Fracture Strength Of Restored Tunnel Preparation With Various Heights Of Marginal Ridge, Phirinat Aurpanchasin
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study aimed to investigate fracture strength of restored tunnel preparation with different marginal ridge heights, using various adhesives and restorative materials. 130 intact premolars were randomly allocated into 13 groups based on 3 remaining marginal ridge heights (1.0, 2.0, and 3.0 mm) and 4 adhesive restorative techniques (Optibond™ FL, ER; selective enamel etching mode Single Bond Universal Adhesive, UA; Equia Forte Fil, HGI and positive control, PC) and negative control (NC). Tunnel preparation and restoration were performed. After 10,000 thermocycled, each specimen underwent fracture strength test until fractured, and evaluated for mode of failure. The data were evaluated using …
The Expression Of Incretin Hormones And Their Receptors In The Submandibular Glands Of Offspring From High Fat Diet-Fed Mother Rats, Pornchanok Sangsuriyothai
The Expression Of Incretin Hormones And Their Receptors In The Submandibular Glands Of Offspring From High Fat Diet-Fed Mother Rats, Pornchanok Sangsuriyothai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Incretins, i.e., glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) promote insulin secretion to reduce postprandial blood sugar. Previous studies found incretins in the salivary glands in rat. However, the role of GLP-1 and GIP in the submandibular gland (SMG) is unclear. This study investigates the effects of a high-fat diet (HFD) on the expression of GLP-1 and GIP throughout the development of rat SMG. Pregnant 11-week-old rats were divided into standard diet and HFD groups (n = 5 each). The newborns were divided into four subgroups (n = 6): standard diet males, HFD males, standard diet females, and HFD …
Effects Of The Cutting Flute Characteristic Of The Orthodontic Miniscrew On Bone Microdamage And Primary Stability, Sansanee Wijarn
Effects Of The Cutting Flute Characteristic Of The Orthodontic Miniscrew On Bone Microdamage And Primary Stability, Sansanee Wijarn
Chulalongkorn University Theses and Dissertations (Chula ETD)
Orthodontic miniscrews was developed as an anchorage. Cutting flute geometry of the screw is important for the stability; however, it has not been fully investigated. This study aim to evaluate the effect of cutting flute geometry on cortical bone microdamage and stability. Human bone analogs, 1.0 mm thick, were prepared alongside custom-made Ti6Al4V screws. These screws, with no flutes or modified flute geometries, came in lengths of 1.2, 2.4, and 5.0 mm, each with rake angles of 0° and 20°. Each screw was inserted into a bone sample and removed while measuring the maximum insertion torque and the maximum removal …
Evaluation Of Tensile Bond Strength Of Various Denture Relining Materials To Conventional And Cad/Cam Manufactured Denture Base Polymers, Pilipda Janyaprasert
Evaluation Of Tensile Bond Strength Of Various Denture Relining Materials To Conventional And Cad/Cam Manufactured Denture Base Polymers, Pilipda Janyaprasert
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study was to investigate the tensile bond strength (TBS) of autopolymerized, heat-polymerized, milled, and 3D printed denture base materials bonded to 2 acrylic-based and 2 silicone-based denture liners, both before and after thermocycling. Four different denture base materials (Palapress (PL), Vertex Rapid Simplified (VR), Smile CAM total prosthesis (SC), and NextDent denture 3D+ (ND)) bonded to 2 acrylic-based (GC Soft-Liner (GC) and Tokuyama Rebase II (RB)) and 2 silicone-based (Ufi Gel P (UP) and Sofreliner Tough M (ST)) denture liners were tested. Specimens (n=8) were divided into non-thermocycling and thermocycling groups. Data were analyzed using 2-way ANOVA and Tukey …
The Comparison Of Learning Outcome Of Dental Implant Placement Training In Esthetic Zone Using Dynamic Navigation System Between Novice Dentists And Experience Dentists, Hatsapon Teparrukkul
The Comparison Of Learning Outcome Of Dental Implant Placement Training In Esthetic Zone Using Dynamic Navigation System Between Novice Dentists And Experience Dentists, Hatsapon Teparrukkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Background: The increasing importance of CAIS in the practice of implant dentistry calls for adequate education and training of clinicians, however little evidence is available to support educational strategies and best practice. Purpose: The aim of this study was to investigate the effectiveness of distributed training with d-CAIS in the accuracy of freehand implant placement by inexperienced operators. Materials and Methods: Six senior dental students without experience in implant placement and dynamic CAIS systems received simulation in free-hand implant surgery (5 implants), followed by distributed training in dynamic CAIS (6 implants). An assessment followed in freehand implant placement (5 implants). …
Autogenous Raw Tooth Particles Versus Xenograft For Alveolar Ridge Preservation: A Prospective Controlled Clinical Trial, Basel Mahardawi
Autogenous Raw Tooth Particles Versus Xenograft For Alveolar Ridge Preservation: A Prospective Controlled Clinical Trial, Basel Mahardawi
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objective: The use of extracted teeth has been recently introduced as an option for bone grafting. However, the current method requires special machines and solutions, which poses significant time and cost. The aim of this study was to evaluate the clinical performance of autogenous Raw Tooth Particles (RTP), a grafting material made from a ground tooth using basic equipment, for alveolar ridge preservation. Materials and methods: 14 and 13 sites (23 patients) were included for the study and control group, respectively. The control group received Bio-Oss® xenograft. Radiographic measurements (in millimeters) were taken at the baseline and at the 4-month …
Oral And Dental Prostheses Status In Mild And Moderate Dementia Patients, Tunyatorn Ratanawatanasin
Oral And Dental Prostheses Status In Mild And Moderate Dementia Patients, Tunyatorn Ratanawatanasin
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study focused on understanding the oral health and dental prostheses status of patients with mild to moderate dementia at King Chulalongkorn Memorial Hospital. A total of 88 patients participated in this cross-sectional study, which utilized the Oral Health Assessment Tool (OHAT) and modified CDA score to evaluate the oral health of patients with a dementia diagnosis. The study revealed significant oral health issues among participants, particularly in terms of gum and oral tissue problems, and oral cleanliness. Although 45.5% of participants had at least 20 functional teeth, a high prevalence of dental decay was observed. Many of the fixed …
Comparison Of The Accuracy Of Implant Placement Between Using Sleeve-In-Sleeve And Integrated Sleeve-On-Drill Drilling Systems For Static Computer-Assisted Implant Surgery: A Simulation-Based Experimental Study, Papon Pattanasirikun
Chulalongkorn University Theses and Dissertations (Chula ETD)
Objective: To investigate precision of implant placement with sleeve-in-sleeve and sleeve-on-drill static Computer Assisted Implant Surgery (sCAIS) designs. Materials and Methods: 32 models were digitally planned and fabricated simulating a patient with bilateral missing first premolar. 8 models were assigned in each group: Group A, B and C represented sleeve-in-sleeve design with 2, 4 and 6mm sleeve height respectively. Group D represented integrated sleeve-on-drill design with 4 mm sleeve height. All models were scanned with CBCT and desktop optical scanner. 16 implants were planned and placed using sCAIS for each group. 3D deviation of placed and planned position at implant …
Geriatric Esthetics: A Comparison Of Prosthodontists, General Practitioners, And Laypeople's Perception, Rawinun Puangkaew
Geriatric Esthetics: A Comparison Of Prosthodontists, General Practitioners, And Laypeople's Perception, Rawinun Puangkaew
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this study, we evaluated the esthetic perceptions of prosthodontists, general practitioners, and laypeople in elderly smile, using varying the exposure of the maxillary incisors in rest position and a full smile, size of buccal corridor and gingival display of maxillary posterior teeth. The picture of elderly smile was modified and shown with randomized sequence. Participants are asked to rate each image by using a numerical visual analog scale (0-10 scale). A total of 150 participants consisted of 50 Thai prosthodontists, 50 general practitioners, and 50 laypeople. Some pictures exhibited statistically significant differences (p0.05). All variation of incisal display were …
Effects Of Jagged1 On Mirna Expression In Dental Stem Cells, Promphakkon Kulthanaamondhita
Effects Of Jagged1 On Mirna Expression In Dental Stem Cells, Promphakkon Kulthanaamondhita
Chulalongkorn University Theses and Dissertations (Chula ETD)
Notch signaling is activated in dental pulp tissues after direct pulp capping treatment in vivo, implying a role in tertiary dentin formation. Furthermore, Notch signaling also participates in periodontal ligament development and maturation. However, its mechanism of action remains to be elucidated. The present study investigated the expression profile of miRNAs in Notch-activated human dental stem pulp stem cells (DPSCs) and periodontal ligament stem cells (PDLSCs), examined their potential cellular targets and validated the functions of miRNAs in modulating the odonto / osteogenic properties. DPSCs and PDLSCs were treated with indirect immobilized Jagged1. The miRNA expression profile was examined using …
การป้องกันการเกิดออกไซด์ของโลหะดีบุกผสมบิสมัท 1% โดยน้ำหนัก, ภควัต พลมณี
การป้องกันการเกิดออกไซด์ของโลหะดีบุกผสมบิสมัท 1% โดยน้ำหนัก, ภควัต พลมณี
Chulalongkorn University Theses and Dissertations (Chula ETD)
การเกิดฟิล์มออกไซด์ในดีบุกผสมบิสมัท 1% โดยน้ำหนักบนแผ่นขัดเงาจากปรากฎการณ์ออกซิเดชัน ทำให้ประสิทธิภาพของผงขัดบนแผ่นขัดเงาลดลง เพื่อให้ทราบถึงอัตราการเกิดออกซิเดชันในสภาวะที่ถูกจำกัดปัจจัยการเกิดฟิล์มออกไซด์คือ ออกซิเจนในรูปแบบต่าง ๆ เช่น ความชื้นในอากาศเป็นต้น จึงได้ทำการหาอัตราการเกิดออกไซด์ที่เกิดขึ้นโดยเทคนิคทางเคมีไฟฟ้า และทำการหาชนิดของฟิล์มที่เกิดขึ้นด้วยเทคนิคโฟโตอิเล็กตรอนสเปกโตสโกปี ปัจจัยที่ส่งผลในการเกิดออกซิเดชันที่ได้ศึกษาในงานวิจัยชิ้นนี้คือ เวลา และสิ่งแวดล้อมที่จำกัดออกซิเจนที่อุณหภูมิห้อง ผลของการทดสอบออกซิเดชันมีดังนี้ ในบรรยากาศปกติความชื้น 28%-35% พบการเกิดออกซิเดชันที่เป็นไปตามกฎของพาราโบลาที่มีสมาการคือ x = 8.7041t0.14 โดยที่ x คือความหนาของฟิล์มและ t คือเวลาที่ใช้ทดสอบออกซิเดชัน ในบรรยากาศแก๊สอาร์กอน, สุญญากาศ, บิวเทน และที่ห่อด้วยพลาสติก ไม่ได้ถูกจำกัดด้วยกฎพาราโบลา และมีแนวโน้มที่ฟิล์มจะมีความหนาน้อยกว่า แต่ต้องการเวลาในการทำการทดสอบมากกว่านี้เพื่อให้ได้ผลและแนวโน้มอัตราที่ชัดเจน ในการวิเคราะห์ผลจากเทคนิคโฟโตอิเล็กตรอนสเปกโตสโกปีในชิ้นงานที่ผ่านการทำออกซิเดชันในสุญญากาศและที่จัดเก็บด้วยการห่อพลาสติก พบว่าทั้งสองชิ้นงานโดยรวมแล้วมีชนิดของฟิล์มออกไซด์เป็นแบบเดียวกัน โดยจะประกอบไปด้วยไอออนของสารประกอบ SnO, SnO2, Sn(OH)2 และ Sn(OH)4 ซึ่งจากผลการทดลอง จะได้แบบจำลองของชั้นฟิล์มออกมาเป็นชั้น ๆ คือ ชั้นที่ 1 เป็นผิวนอกสุดมีออกไซด์ SnO2 และ Sn(OH)4 อยู่เป็นกลุ่มก้อนไม่สม่ำเสมอ (คลัสเตอร์) ชั้นที่ 2 เป็น SnO และ Sn(OH)2 ชั้นที่ 3 เป็น SnO2 และ Sn(OH)4
Loss Comparison Study Of Two-Level And Three-Level Inverters For Electric Vehicle Drives, Kaninnat Rosdee
Loss Comparison Study Of Two-Level And Three-Level Inverters For Electric Vehicle Drives, Kaninnat Rosdee
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis investigates the efficiency of wide bandgap (WBG) semiconductor devices, specifically silicon carbide (SiC) and gallium nitride (GaN), in electric vehicle (EV) traction drive systems using two-level and three-level voltage source inverters (VSIs). The research aims to compare power losses and efficiency improvements by employing WBG devices in the inverters. Simulation results demonstrate that WBG devices significantly reduce conduction and switching losses in both inverter topologies compared to conventional silicon insulated-gate bipolar transistors (Si-IGBTs). SiC MOSFET, in particular, shows over 40% reduction in conduction losses and over 60% reduction in switching losses, leading to an overall efficiency improvement of …
Covalent Organic Frameworks Based On Aldehyde And Amine Linkers As Artificial Solid Electrolyte Interphase For Zinc Anode In Aqueous Electrolyte, Vipada Aupama
Chulalongkorn University Theses and Dissertations (Chula ETD)
Aqueous Zinc-based batteries (AZBBs) are an alternative battery technology being developed for commercial use due to their advantages such as low cost, safety, and eco-friendliness compared to Lithium-based batteries (LBBs). However, despite these benefits, AZBBs face challenges on the zinc anode, including the formation of zinc dendrites and side reactions, which reduce the battery's stability and lifespan. Recently, many strategies have been investigated to address these issues, such as modifying the electrolyte, separator, and anode structure, and specially modifying the zinc surface. One particularly promising strategy involves using an Artificial Solid Electrolyte Interphase (ASEI) developed from a covalent organic framework …
The Effect Of Oxygen Vacancies On The Catalytic Performance For The Ketonization Of Methyl Palmitate Into Palmitone, Mohammad Yazdanpanah
The Effect Of Oxygen Vacancies On The Catalytic Performance For The Ketonization Of Methyl Palmitate Into Palmitone, Mohammad Yazdanpanah
Chulalongkorn University Theses and Dissertations (Chula ETD)
The ketonization of bio-derived fatty acid methyl esters (FAMEs) into added-value products is an increasingly attractive process. However, the role of oxygen vacancies (Ov) in thermal catalytic performance and catalyst lattice oxygen loss has received less attention. This study investigated the relationship between Ov level, acid-base density, and catalytic performance in the ketonization reaction using TiOx catalysts with varying Ov levels prepared by a modified sol-gel method. Density functional theory (DFT) simulations showed that Ov creation increased interatomic distances, leading to the formation of frustrated Lewis pairs (FLPs). The density of acidic and basic sites increased proportionally with Ov concentration. …
Ambient And Elevated Temperature Performance Of Geopolymer Concrete Containing Rubber And Graphene Nanoplatelets, Hafiz Waheed Iqbal
Ambient And Elevated Temperature Performance Of Geopolymer Concrete Containing Rubber And Graphene Nanoplatelets, Hafiz Waheed Iqbal
Chulalongkorn University Theses and Dissertations (Chula ETD)
Geopolymer concrete (GPC) is recognized as a promising alternative to conventional cement concrete due to its environmental sustainability properties. In this research work, crumb rubber (CR) was used to partially replace fine aggregate to reduce rubber waste, and graphene nanoplatelets (GNPs) were used as a nanomaterial to enhance the properties of GPC. Total 20 mix designs of fly ash-based GPC were made having 10% to 30% replacement of fine aggregate with CR and addition of 0.1% to 0.4% of GNPs as of binder percentage. The main objective of this research work is to assess the properties of these mix designs …
Single Spring Gravity Compensator For A Multi Degree Of Freedom Manipulator Arm, Krittanai Sajjapongse
Single Spring Gravity Compensator For A Multi Degree Of Freedom Manipulator Arm, Krittanai Sajjapongse
Chulalongkorn University Theses and Dissertations (Chula ETD)
Designing industrial robots requires utmost attention to power consumption and safety, especially in today's environment where humans work closely with robots. However, due to their robust and weighty structures, most robotic manipulators are typically engineered with high-power systems to handle payloads and counteract gravity. This research develops a novel gravity compensator system that employs a single spring to counterbalance a multi-DOF manipulator. This system combines cam follower systems with a square root mechanism. We provide a general equation that applies to multiple degrees of freedom. Additionally, we designed and built a 3-DOF manipulator prototype. The experiment shows that our gravity …
Reactor Design By Integrating Absorption And Photocatalytic Oxidation Processes For Volatile Organic Compound (Voc) Removal From Polluted Gas Stream Of Storage Facilities In Petrochemical Industry, Phaly Ham
Chulalongkorn University Theses and Dissertations (Chula ETD)
Even petrochemical industry plays an important role in meeting the global energy demand, it is also responsible for emitting significant amounts of Volatile Organic Compounds (VOCs), which pose serious environmental and health hazards. In this thesis, we propose an innovative approach to address this issue by designing a multifunctional reactor that integrates absorption and photocatalytic oxidation processes for the removal of VOC from polluted gas streams of storage facilities, during loading, discharging, and cleaning process. This research encompasses four scopes (i) Comparative study of gas-liquid contactors: Bubble Column Reactor (BCR) and internal-loop Airlift Reactor (IL-ALR). The relative effect of reactor’s …
Novel Pricing Structure And Mechanism With Consideration Of Network Usage Charges For Peer-To-Peer Energy Trading In Distribution Systems Of Thailand, Surapad Larbwisuthisaroj
Novel Pricing Structure And Mechanism With Consideration Of Network Usage Charges For Peer-To-Peer Energy Trading In Distribution Systems Of Thailand, Surapad Larbwisuthisaroj
Chulalongkorn University Theses and Dissertations (Chula ETD)
The rise of distributed energy resources has empowered consumers to become prosumers, generating their own electricity. This trend has led to the development of peer-to-peer (P2P) energy trading. This dissertation focuses on two main areas: integrating network charges in P2P energy trading and determining the maximum P2P penetration levels on distribution systems while considering stakeholder benefits. Firstly, a framework for network usage charges (NUCs) and corresponding market clearing mechanisms are proposed. The NUCs comprise two key components: distribution NUCs (DNUCs) and operational NUCs (ONUCs). These charges are designed to recover energy-related and nonenergy-related costs incurred in the distribution system. DNUCs …
Improving Player Skills In Action Games Using Dynamic Scripting Ai, Pakanan Aimherungilas
Improving Player Skills In Action Games Using Dynamic Scripting Ai, Pakanan Aimherungilas
Chulalongkorn University Theses and Dissertations (Chula ETD)
Complexity in video games is one of the obstacles that prevent new players from enjoying the game. In an action game genre, players require a certain level of reaction time and game knowledge to overcome a challenge. Players have difficulty learning and improving their skills in complex games. One example being Final Fantasy VIII and its tutorial about magic junction system, the main mechanic of the game that the game quickly explained with numerous texts. Due to its complexity, most players could not understand the mechanic properly, leaving them confused and having a hard time playing the game. Players who …
Utilization Of Plasma Technology For De-Inking And Hydrogenation Without Catalyst, Ika Priyanti
Utilization Of Plasma Technology For De-Inking And Hydrogenation Without Catalyst, Ika Priyanti
Chulalongkorn University Theses and Dissertations (Chula ETD)
Catalyst-free plasma technologies have been successfully utilized for de-inked and hydrogenated processes. These green methods have nonchemical contributions, operating at room temperature and atmospheric pressure, reducing the environmental impact of the process. Two plasma types and arrangements were studied in this research: corona plasma (de-inking) and dielectric barrier discharge plasma (hydrogenation). The results found that the deinkability factors were 48.58% (yellow printed paper), 64.11% (blue printed paper), and 41.11% (red printed paper) without altering the physical properties of the paper itself. The change in the tensile strength for the plasma-exposed paper was relatively little, less than 10%, compared to that …
Removal Of Perfluorooctanoic Acid (Pfoa) In Water With Dbd-Plasma-Enhanced Adsorbent, Thera Sahara
Removal Of Perfluorooctanoic Acid (Pfoa) In Water With Dbd-Plasma-Enhanced Adsorbent, Thera Sahara
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study examined the enhancement of PFOA removal from water using DBD plasma-modified adsorbents, specifically rice husks (RHs) and granular activated carbon (GAC). RHs treated with He-O2 plasma after phosphoric acid activation demonstrated a significant increase in adsorption efficiency, improving from 46.4% to 92.0% under optimal conditions. Adjusting pH to 4 further increased efficiency to 96.7%. The adsorption process followed the Langmuir model and pseudo-second-order kinetics, with a maximum capacity of 565 mg/g. The effects of DBD plasma on GAC in the presence of natural organic matter (NOM) were also assessed. Optimal plasma treatment enhanced PFOA removal in both deionized …
Convolutional Neural Network Based Wireless Channel Estimation And Impact Of Estimation On Hybrid Precoding, Sunita Khichar
Convolutional Neural Network Based Wireless Channel Estimation And Impact Of Estimation On Hybrid Precoding, Sunita Khichar
Chulalongkorn University Theses and Dissertations (Chula ETD)
Channel estimation is vital in wireless communication systems, influencing overall performance and efficiency. This thesis presents three contributions to enhance channel estimation techniques for next-generation systems. Firstly, we propose a modified ChannelNet, CNN for estimating fast-fading channels in OFDM systems. By replacing traditional linear interpolation with zero padding and using SRCNN and FSRCNN, we significantly reduce complexity while maintaining MSE performance comparable to linear minimum MSE estimation. This approach balances efficiency and accuracy for fast-fading channel estimation. Secondly, we examine the impact of the number of radio frequency (RF) chains and training power on channel estimation in massive MIMO downlink …
Virtual Reality Of Labless Foundry And Heat Treatment For Next Industrial Training, Naris Lawankowit
Virtual Reality Of Labless Foundry And Heat Treatment For Next Industrial Training, Naris Lawankowit
Chulalongkorn University Theses and Dissertations (Chula ETD)
This study presents an innovative Virtual Reality (VR) application tailored to educate users on Foundry and Heat Treatment operations. Its primary objectives encompass the creation of a secure and lifelike learning environment while ensuring accessibility. The development process was a meticulous fusion of technology, incorporating the Unity engine, 3D modeling, and seamless Salesforce integration, all grounded in extensive research. The VR application's structure strategically subdivides these industrial processes into four stations: Molding, Furnace, Workbench, and Heat Treatment. This detailed approach empowers users to engage directly in these operations, making it a valuable educational tool. The study's significance extends to the …
Solubility And Anti-Cancer Efficiency Enhancement Of Phytochemicals By Complexation With Β-Cyclodextrin And Derivatives, Saba Ali
Chulalongkorn University Theses and Dissertations (Chula ETD)
Phytochemicals, abundant in plants, showcase diverse pharmacological effects, with an increasing focus on their potential as anticancer agents. Three bioactive natural compounds with pharmaceutical potential are piperine (PP), oxyresveratrol (OXY), and tanshinone IIA (Tan IIA). However, these three phytochemicals have low water solubility and susceptibility to UV light degradation. To address this problem, we explored the potential of β -cyclodextrins (βCDs), renowned for their ability to enhance the solubility and stability of lipophilic drugs by encapsulating them within their molecular structure. Our focus centered on β-cyclodextrin (βCD) and its derivatives, including hydroxypropyl-β-cyclodextrin (HPβCD), dimethyl-β-cyclodextrin (DMβCD), and sulfobutylether-β-cyclodextrin (SBEβCD). In this …
Design, Synthesis, And Biological Evaluation Of Darunavir Analogs As Hiv-1 Protease Inhibitors, Muhammad Asad Ur Rehman
Design, Synthesis, And Biological Evaluation Of Darunavir Analogs As Hiv-1 Protease Inhibitors, Muhammad Asad Ur Rehman
Chulalongkorn University Theses and Dissertations (Chula ETD)
Darunavir, a potent inhibitor for HIV protease (PR) for the treatment of HIV infection, encounters limitations due to the emergence of multi-drug resistance HIV strains, imposing the development of darunavir analogs as new HIV protease inhibitors (PI) with enhanced efficacy. In this study, a combinatorial in silico method was used to at first design a several HIV-1 PI analogs with variations at key sites, P1' and P2', to improve the interactions with HIV-1 PR. Fifteen analogs with encouraging binding score were selected for synthesis and assessed for the inhibition activity of HIV-1 PR. The study demonstrated the effectiveness of P2' …
Hydrophobic Deep Eutectic Solvent-Based Ferrofluid For Removal Of Parabens, Aswin Falahudin
Hydrophobic Deep Eutectic Solvent-Based Ferrofluid For Removal Of Parabens, Aswin Falahudin
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hydrophobic deep eutectic solvent-based ferrofluids were prepared by combining magnetic nanocomposites and hydrophobic deep eutectic solvent, and studies for paraben removal were conducted. The final products were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, surface area analyzer, scanning electron microscopy, thermogravimetric analysis, vibrating sample magnetometer, and UV-Vis spectrophotometer. SEM images and XRD pattern showed that the magnetic nanocomposite particles are mostly spherical and the magnetite phase of iron oxide and amorphous silica. The surface area of these materials ranged from 97.02 m2/g for the bare magnetite to 132.80 m2/g, 292.74 m2/g, and 421.88 m2/g after modified with silica shell …
Simplified Music Playlist Recommendation Using Sequential-Based Gated Recurrent Unit For Policy And Action Determination, Chanapa Channarong
Simplified Music Playlist Recommendation Using Sequential-Based Gated Recurrent Unit For Policy And Action Determination, Chanapa Channarong
Chulalongkorn University Theses and Dissertations (Chula ETD)
Recommendation systems are crucial for helping users discover music tailored to their preferences on streaming services. Reinforcement learning is a popular method for music recommendations. However, previous approaches have struggled with overfitting. The agent may become problematic for the new user context if, after a learning phase, it starts to predict actions only based on previous interactions. To overcome this limitation, previous methods require retraining, which require resetting all parameters in the agent. This study introduces the Policy GRU-RL method, which combines sequential-based learning and reinforcement learning to address overfitting without resetting all parameters. It utilizes a recurrent network by …