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Full-Text Articles in Physical Sciences and Mathematics

Theoretical Approaches To Food Waste Behaviours: An Overview, Dane Chia, Chin Choo Yap, Mohamed Kheireddine Aroua, Lai Ti Gew Jan 2024

Theoretical Approaches To Food Waste Behaviours: An Overview, Dane Chia, Chin Choo Yap, Mohamed Kheireddine Aroua, Lai Ti Gew

Applied Environmental Research

Food waste around the world has emerged as a pressing issue that calls for attention and intervention. Analysing the food waste problem without understanding wasteful behaviour antecedents may oversimplify this multi-faceted issue, which will then compromise the development of interventions. This paper provides an overview of the theoretical approaches to food waste behaviour antecedents, followed by evidence-based interventions, using the Theory of Planned Behaviour (TPB), the Norm Activation Model (NAM), and the Social Practice Theory (SPT). These theories encompass the psychological, behavioural, societal, material, and structural factors that influence food waste practices. Our aim is to provide a holistic understanding …

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Assessing The Relationship And Effect Of Air Pollution [Pm 2.5] On Child Respiratory Illness And Child Mortality In The Philippines, Roel F. Ceballos, Rachell C. Gallano, Lenard D. Visaya Jan 2024

Assessing The Relationship And Effect Of Air Pollution [Pm 2.5] On Child Respiratory Illness And Child Mortality In The Philippines, Roel F. Ceballos, Rachell C. Gallano, Lenard D. Visaya

Applied Environmental Research

Air pollution is the presence of harmful substances in the air, which can seriously impact human health and the environment. Among the air pollutants, fine particulate matter (PM) 2.5, being a microscopic particle, poses serious health risks since it can enter the blood circulation and go deep into the lungs. PM 2.5 has been linked to several health problems, such as early mortality, problems with children's development, and unfavorable birth outcomes. In this regard, the study aims to investigate the relationship and effect of PM 2.5 on child respi-ratory illness and child mortality in the Philippines. Data on child respiratory …

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Exposure To Metal Accumulation In Chicken Giblets And Human Health Risk In Lokoja, Nigeria, Jude Ehwevwerhere Emurotu, Lami Habib, Ephraim Musa Dallatu, Adamu Shuaibu Onakpa, Aloysius Akaangee Pam Jan 2024

Exposure To Metal Accumulation In Chicken Giblets And Human Health Risk In Lokoja, Nigeria, Jude Ehwevwerhere Emurotu, Lami Habib, Ephraim Musa Dallatu, Adamu Shuaibu Onakpa, Aloysius Akaangee Pam

Applied Environmental Research

When consumed, the toxic heavy metals in chicken giblets pose a grave risk to humans. An inductively coupled plasma optical emission spectrometer (ICP-OES) was used to measure the concentrations of metals (Al, Cd, Co, Cr, Ni, Mn, and Pb) in the liver, gizzard, and kidney of chickens from the Lokoja poultry market. Except for lead, which slightly exceeded the FAO/WHO limit of 0.1 mg kg-1, the metal concentrations found were all within the threshold limit. The estimated daily intake (EDI), hazard quotient (HQ), hazard index (HI), and cancer risk (CR) were used to assess the risks that humans would face …

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Assessing The Short- And Long-Term Health Effects Of Nitrogen Dioxide In Agadir, Morocco: A Who Airq+ Model Application, Youssef Bouchriti, Mohamed Ait Haddou, Abderrahmane Achbani, Amal Korrida, Hasnaa Sine, Jamila Rida, Mohamed Boukrim, Belkacem Kabbachi Jan 2024

Assessing The Short- And Long-Term Health Effects Of Nitrogen Dioxide In Agadir, Morocco: A Who Airq+ Model Application, Youssef Bouchriti, Mohamed Ait Haddou, Abderrahmane Achbani, Amal Korrida, Hasnaa Sine, Jamila Rida, Mohamed Boukrim, Belkacem Kabbachi

Applied Environmental Research

Epidemiological studies have revealed that exposure to atmospheric nitrogen dioxide (NO2) increases the risk of acute and chronic diseases. This study used the WHO AirQ model to assess both the short- and long-term impacts of NO2 on human health in the city of Agadir in Morocco. The mean NO2 values were obtained from measurements taken at two locations. This study assessed the long- term health effects of NO2 on natural all-cause mortality (LT-ACM), mortality due to respiratory diseases (LT-RD), and morbidity due to chronic obstructive pulmo-nary disease (LT-COPD), as well as the short-term health impacts of NO2 on natural all-cause …

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Minimization The Chemical Oxygen Demand (Cod) Content In Tannery Wastewater Using Activated Carbon From Spent Tea Leaves, Kanish Fatama, Nasifa Akter, Badhan Saha, Nur -E- Alam Md., Shimul Chakma Jan 2024

Minimization The Chemical Oxygen Demand (Cod) Content In Tannery Wastewater Using Activated Carbon From Spent Tea Leaves, Kanish Fatama, Nasifa Akter, Badhan Saha, Nur -E- Alam Md., Shimul Chakma

Applied Environmental Research

Water pollution from tannery wastewater is a serious environmental issue. This study aimed to investigate the potential of spent tea leaves as activated carbon (AC) to minimize chemical oxygen demand (COD) of tannery effluent. To determine the best conditions for minimizing COD, a batch adsorption process was conducted, involving various factors such as different adsorbent dosages (ranging from 1 to 11 gm L-1), contact time (30 to150 min), and pH values (ranging from 3 to 11). The characterization was done by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM). The outcomes of this study demonstrated that using 1.5 M …

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Unveiling Long-Term Impacts Of Forest Cover Changes And Carbon Storage Assessment In Nan Province, Thailand, Jiratiwan Kruasilp, Sura Pattanakiat, Siam Lawawirojwong, Thamarat Phutthai, Poonperm Vardhanabindu, Warinthorn Kiadtikornthaweeyot Evans, Anne Jacquine Jan 2024

Unveiling Long-Term Impacts Of Forest Cover Changes And Carbon Storage Assessment In Nan Province, Thailand, Jiratiwan Kruasilp, Sura Pattanakiat, Siam Lawawirojwong, Thamarat Phutthai, Poonperm Vardhanabindu, Warinthorn Kiadtikornthaweeyot Evans, Anne Jacquine

Applied Environmental Research

Forests serve as carbon sink by storing and sequestrating carbon dioxide from the atmosphere. Forest cover loss adversely affects communities by increasing risks to the shortage of carbon storage. This study provides a comprehensive understanding of forest fragmentation and assessment of forest cover changes impacts on carbon storage over Nan province during 1990 to 2019. Spatial and temporal patterns were explored using landscape metrics analysis. Forest areas declined 10.69% over 30 years using random forest classifier based on Google Earth Engine platform, with an overall accuracy of 97.10%. The highest rate of forest cover changes was 5.27% (2010 to 2014), …

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Junkshops As Recycling Chain Actors In The Recovery Of Waste Resources From A Highly Urbanized City In The Philippines, Aries Roda D. Romallosa, Mary O’ T. Mary O’ T. Penetrante, Neil G. Ravena Jan 2024

Junkshops As Recycling Chain Actors In The Recovery Of Waste Resources From A Highly Urbanized City In The Philippines, Aries Roda D. Romallosa, Mary O’ T. Mary O’ T. Penetrante, Neil G. Ravena

Applied Environmental Research

This study was performed in order to identify the role and work mechanism of the 33 junkshops in the recovery of valuable recyclable materials for further processing by the next level hierarchy of recycling chain actors in Iloilo City, Philippines. Results revealed that more than 65% of the junkshops operate at 7 to 8 hours per day, hire 1 to 4 male workers, operate at an area of 50 to 1000 m2 with structures made of light materials, and with a capital outlay of 

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Life Cycle Comparative Assessment Of Polyethylene Terephthalate (Pet) Plastic Bottles: A Case Study Of Drinking Bottled Water In Ramathibodi Hospital, Thailand, Anuchan Panaksri, Nuankanya Sathirapongsasuti, Cha-Re Thangto, Kittisak Jantanasakulwong, Pornchai Rachtanapun, Cholrit Luangjinda, Chairat Mekkaew, Phanom Suha, Nuntachai Thongpance, Sani Boonyagul, Nuttapol Tanadchangsaeng Jan 2024

Life Cycle Comparative Assessment Of Polyethylene Terephthalate (Pet) Plastic Bottles: A Case Study Of Drinking Bottled Water In Ramathibodi Hospital, Thailand, Anuchan Panaksri, Nuankanya Sathirapongsasuti, Cha-Re Thangto, Kittisak Jantanasakulwong, Pornchai Rachtanapun, Cholrit Luangjinda, Chairat Mekkaew, Phanom Suha, Nuntachai Thongpance, Sani Boonyagul, Nuttapol Tanadchangsaeng

Applied Environmental Research

In the current context where all sectors aim to promote sustainable development, hospitals, as large organizations with significant human interactions, face challenges in managing not only medical waste but also general waste such as water bottles. Improper management of these wastes can lead to environmental problems and high disposal costs. This study performed a life cycle assessment (LCA) of regular (petroleum-based) and alternative (bio-based) polyethylene terephthalate (PET) bottles used in Ramathibodi Hospital, Thailand, to identify effective strategies for mitigating environmental impacts. The assessment was divided into three scenarios: label-free bottles, bio-based bottles, and 100% recycling. The results indicate that using …

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Spatiotemporal Patterns Of Land Surface Temperature, Urban Heat Island, And Potential Heat Stress Risk Areas Assessment For Tropical Inland City And Coastal City In Thailand, Thar Htet Aung, Sakpod Tongleamnak, Rasamee Suwanwerakamtorn Jan 2024

Spatiotemporal Patterns Of Land Surface Temperature, Urban Heat Island, And Potential Heat Stress Risk Areas Assessment For Tropical Inland City And Coastal City In Thailand, Thar Htet Aung, Sakpod Tongleamnak, Rasamee Suwanwerakamtorn

Applied Environmental Research

Global warming and rapid urban growth, compounded by the urban heat island (UHI) effect, are posing substantial challenges for urban populations and ecological well-being due to increased heat stress risks. This study aimed to analyze the spatiotemporal patterns of land surface temperature (LST), UHI, and potential heat stress risk areas (PHSRA) in two distinct cities, an inland city, Nakhon Ratchasima, and a coastal city, Si Racha, during the summer. Geoinformatics techniques and Crichton’s Risk Triangle method were employed, using updated demographic data and Sentinel-3 data from 2017 to 2022. The findings indicate that the inland city daytime average LST values …

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Geospatial Modelling Of Flood Susceptibility Of The Calabar City, Cross River State, Nigeria, Joel Efiong, Eme Efiong, Oluyemi Akintoye, Ebin Inah, Obianuju Awan, Francis Ogban Jan 2024

Geospatial Modelling Of Flood Susceptibility Of The Calabar City, Cross River State, Nigeria, Joel Efiong, Eme Efiong, Oluyemi Akintoye, Ebin Inah, Obianuju Awan, Francis Ogban

Applied Environmental Research

Flooding remains a major environmental problem in many parts of the world including Nigeria, causing untold losses. This study modelled the flood susceptibility of Calabar Metropolis using frequency ratio and geographical information system (GIS). Direct field observation and key informant approaches were used to obtain 127 previous and current flood locations in the study area from which a database of historical flood occurrence was developed. Using the geostatistical analyst tool within a geographical information environment the flood locations were split into two parts in the ratio of 70:30 percent for the training and testing processes, respectively. Eight flood conditioning factors …

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A Review On Chemometrics And Climate Change: Insights From Malaysia Case Study, Ismafatin Nabilah Ismail, Mohd Khairul Amri Kamarudin, Wan Nor Azilawanie Tun Ismail, Noorjima Abd Wahab, Ahmad Shakir Mohd Saudi, Mohd Ekhwan Toriman, Firdaus Mohamad Hamzah, Septi Ariadi Jan 2024

A Review On Chemometrics And Climate Change: Insights From Malaysia Case Study, Ismafatin Nabilah Ismail, Mohd Khairul Amri Kamarudin, Wan Nor Azilawanie Tun Ismail, Noorjima Abd Wahab, Ahmad Shakir Mohd Saudi, Mohd Ekhwan Toriman, Firdaus Mohamad Hamzah, Septi Ariadi

Applied Environmental Research

Climate change consider as main issues and concerns in Malaysia over the decade. Chemometrics techniques have been used in many climate change issues to address the limitations of climate change monitoring studies. In climate change areas, chemometrics is a valuable tool for assessing the correlation between different climate change factors, especially in vast and intricate databases. The purpose of the review was to evaluate and summarise the available data and restrictions regarding the use of chemometrics techniques in Malaysian environmental studies. The study conducted a thorough analysis of pertinent scientific papers published between 2019 to 2023 that addressed the main …

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Outlooks And Challenges For Urban Green Space Development: A Review Case Study In Thailand, Kanawat Paoin, Chanathip Pharino Jan 2024

Outlooks And Challenges For Urban Green Space Development: A Review Case Study In Thailand, Kanawat Paoin, Chanathip Pharino

Applied Environmental Research

Even though prior studies have provided ample proof of the benefits of urban green space, Thailand's development and exploitation of urban green space remain insufficiently efficient. To assess the prospects for urban green space development in Thailand, our review study highlighted gaps and challenges related to these areas. This review study discussed the rationale for urban green space, its definitions, as well as its benefits and co-benefits (i.e., economic, social, health, and environmental). The review research additionally discussed Thailand's current urban green space issues, associated challenges (such as difficulties valuing and using urban green space, budgetary limitations, low priority for …

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Optimizing Tenebrio Molitor Feeding Strategy To Induce Physical Degradation Of Tires: A Novel Approach For Sustainable Waste Management, Abdussalam Topandi, Khadijah Sayyidatun Nisa, Fatimah Azizah Riyadi, Ibnu Maulana Hidayatullah, Pranata -, Firah Gustianda Ayu, Reynaldi Ivan Prasetya, Frederick Soetandar, Dimas Rafi Narawangsa, Eka Rahayu Jan 2024

Optimizing Tenebrio Molitor Feeding Strategy To Induce Physical Degradation Of Tires: A Novel Approach For Sustainable Waste Management, Abdussalam Topandi, Khadijah Sayyidatun Nisa, Fatimah Azizah Riyadi, Ibnu Maulana Hidayatullah, Pranata -, Firah Gustianda Ayu, Reynaldi Ivan Prasetya, Frederick Soetandar, Dimas Rafi Narawangsa, Eka Rahayu

Applied Environmental Research

Due to the increased usage of tires, the accumulation of worn tires has become a significant environmental concern and necessitates environmentally friendly waste management strategies. Conventional methods, such as tire incineration or improper disposal, contribute to environmental degradation. It is reported that organisms, such as Tenebrio molitor larvae, can degrade a wide range of polymers. This study explores the promising potential of Tenebrio molitor larvae in addressing this concern. Through a series of experiments, Tenebrio molitor larvae were fed with cut-worn tires to facilitate degradation. The larvae exhibited remarkable capabilities, surviving and thriving on tires as a sole carbon source …

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Enzyme Activity And Biodegradation Potentials Of Serratia Marcescens Cell-Free Extract On Polyethylene Terephthalate Sheet, Ogunjemite Oluwadamilola E, Folasade M. Olajuyigbe Jan 2024

Enzyme Activity And Biodegradation Potentials Of Serratia Marcescens Cell-Free Extract On Polyethylene Terephthalate Sheet, Ogunjemite Oluwadamilola E, Folasade M. Olajuyigbe

Applied Environmental Research

Microbial strains with potential hydrolytic enzymes are excellent hosts for the biodegradation of polyethylene terephthalate (PET). However, knowledge of the best working conditions for enzymatic actions is essential to suggest the most suitable condition for the bio-transformation process. In this research, PETase and lipase produced by Serratia marcescens under PET exposure were screened and their physicochemical properties were evaluated. Furthermore, the biodegradation efficiency of the cell-free extract produced from S. marcescens on a PET sheet was studied via scanning electron microscope (SEM) and Fourier transform infrared spectrophotometer (FTIR). The result showed maximum production of PETase activity (8.80 U mL-1) and …

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Microplastic Contamination In Table Salt: A Study Of Consumer Behavior In Cox's Bazar, Bangladesh, Sk Abid Md Saad, Faijunnesa Rashid, Maisha Miskat, Mukul Chandra Sarker, Arman Khan, Mustafizur Rahman Jan 2024

Microplastic Contamination In Table Salt: A Study Of Consumer Behavior In Cox's Bazar, Bangladesh, Sk Abid Md Saad, Faijunnesa Rashid, Maisha Miskat, Mukul Chandra Sarker, Arman Khan, Mustafizur Rahman

Applied Environmental Research

Plastic particles resulting from the breakdown of bigger plastics may be introduced directly as micro- and nano-sized particles polluting the marine ecosystem, including ocean-extracted table salt. This study investigated the presence of microplastic (MP)-like particles in table salt from Bangladesh, focusing on both locally refined and commercially branded varieties. Local salt samples from Sadar and Moheshkhali Sub-district of Cox’s Bazar contained an average of 23.4 and 12 particles kg-1, respectively. In contrast, no particles were detected in commercial brands, likely due to their complex refining processes. The study also explored factors influencing local salt consumption, finding it influenced by the …

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Assessment Of Total Petroleum Carbon And Heavy Metals Of Some Selected Plants Grown In Crude Oil Polluted Soils Using Gc-Fid, Pius O. Adah, Ndem E. Edu, Reagan B. Agbor, Henry B. Kogbara Jan 2024

Assessment Of Total Petroleum Carbon And Heavy Metals Of Some Selected Plants Grown In Crude Oil Polluted Soils Using Gc-Fid, Pius O. Adah, Ndem E. Edu, Reagan B. Agbor, Henry B. Kogbara

Applied Environmental Research

This study was focused on assessing the phytoremediation potentials of some selected plant species on crude oil contaminated soils. Five plant species were cultivated in soils polluted with crude oil at 10, 50, 100, 150 and 200 mg kg-1. The results revealed that there were significant reduction in THC contents of soil ameliorated with the various plants species compared to the control group increases with increasing concentration of crude oil pollutant in soil. THC was 62.24 mg kg-1, 1,120 mg kg-1, 208.67 mg kg-1, 257.87 mg kg-1 and 2,762.79 mg kg-1 for R. simplex, P. balfouriana, K. pinnata …

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Study Of Solar Collector Potential In Thailand Using Computational Fluid Dynamics Approach, Phongpapop Kitisomkiat, Varudom Siri, Benjapon Chalermsinsuwan, Kejvalee Pruksathorn Jan 2024

Study Of Solar Collector Potential In Thailand Using Computational Fluid Dynamics Approach, Phongpapop Kitisomkiat, Varudom Siri, Benjapon Chalermsinsuwan, Kejvalee Pruksathorn

Applied Environmental Research

Due to the proximity of Thailand being near the equator, there is a significant potential for harnessing an excess amount of solar energy using a solar collector. The solar collector harvests solar energy by acting as a passive heat exchanger, receiving solar energy, and transferring it to a fluid medium to be further utilized. This study presents the analysis of temperature outlet and pressure drop of a solar collector in Thailand, utilizing Earth’s geological location, date, and time for solar energy calculations and employing computational fluid dynamics (CFD) to predict the collector’s efficiency. The CFD approach offers a reduction in …

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Food Waste From Catering Services In Thai Hotels: A Composition Analysis And Practical Guidelines For Effective Utilization, Patranit Srijuntrapun, Patinya Sukwong Jan 2024

Food Waste From Catering Services In Thai Hotels: A Composition Analysis And Practical Guidelines For Effective Utilization, Patranit Srijuntrapun, Patinya Sukwong

Applied Environmental Research

Food waste from the hotel sector is a significant contributor to the overall volume of food waste, particularly in restaurants and food services through various processes. However, precise data on food waste generated by the hotel industry is lacking. This study aims to quantify and characterize the food waste generated during the preparation and serving processes in hotel catering, with the goal of finding efficient solutions to reduce food waste that are appropriate for the hotel and catering sectors. The study presents novel findings that among the different types of catering, dinner-style buffets (DB) generate the highest amount of food …

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Review Of How Ai Works: From Sorcery To Science, By Ronald T. Kneusel, Taylor J. Greene Jan 2024

Review Of How Ai Works: From Sorcery To Science, By Ronald T. Kneusel, Taylor J. Greene

Library Articles and Research

A review of How AI Works: From Sorcery to Science, by Ronald T. Kneusel.

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Review Of Who Wrote This?: How Ai And The Lure Of Efficiency Threaten Human Writing, By Naomi S. Baron, Taylor J. Greene Jan 2024

Review Of Who Wrote This?: How Ai And The Lure Of Efficiency Threaten Human Writing, By Naomi S. Baron, Taylor J. Greene

Library Articles and Research

A review of Who Wrote This?: How AI and the Lure of Efficiency Threaten Human Writing, by Naomi S. Baron.

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Prime Intersection Graphs Of Ideals Of Commutative Artinian Rings, Nuttawut Sangjaer Jan 2024

Prime Intersection Graphs Of Ideals Of Commutative Artinian Rings, Nuttawut Sangjaer

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, we study prime intersection graphs of ideals of commutative Artinian rings. We work on the connectedness, completeness and planarity of the graphs and characterize the star graphs for these graphs. We calculate graph \linebreak parameters and find the radius and a center of the graphs. Moreover, we determine the degree of each vertex when the vertex set is finite, and characterize the Eulerian and Hamiltonian properties of the graphs.

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Prediction Of Optimal Binding Constraints Of Linear Programming Problem Using Deep Learning, Natdanai Kafakthong Jan 2024

Prediction Of Optimal Binding Constraints Of Linear Programming Problem Using Deep Learning, Natdanai Kafakthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis presents innovative deep learning models designed to enhance the efficiency of solving linear programming, transportation, and traveling salesman problems. The first model, LP-Net, predicts the binding optimal constraints in linear programming problems, achieving faster solution times compared to traditional solvers like CPLEX. The second model, Transport-Net, predicts optimal basic feasible arcs for transportation problems, demonstrating significant speedups and superior scalability over both CPLEX and Gurobi in large-scale instances. The third model, TSP-Net, addresses the traveling salesman problem by predicting an initial near-optimal tour, outperforming Gurobi and genetic algorithms in computational efficiency. Collectively, these deep learning approaches offer transformative …

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Fuzzy Digital Signature Scheme For Binary Noisy Strings With Respect To Hamming Distance, Ittanee Srikham Jan 2024

Fuzzy Digital Signature Scheme For Binary Noisy Strings With Respect To Hamming Distance, Ittanee Srikham

Chulalongkorn University Theses and Dissertations (Chula ETD)

One of the risks associated with public key infrastructure (PKI) pertains to the security of the user's private key. Given the imperative for stringent protection of this key, a proposed solution to mitigate this risk involves the utilization of biometric information. Although biometric information is fuzzy, it cannot be used directly as a cryptographic key. Thus, our investigation commenced into the exploration of ``Signature Scheme with a Fuzzy Private Key" by Takahashi et al. They introduced a new concept of digital signature called ``fuzzy signature" for real vectors with $L_{\infty}$ metric. A fuzzy signature is a signature scheme that uses …

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Adjustment Of Ridge Estimator For Linear Regression Model With Multicollinearity, Sittinon Pumpuang Jan 2024

Adjustment Of Ridge Estimator For Linear Regression Model With Multicollinearity, Sittinon Pumpuang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Linear regression model is one of important statistical tools applied in many different problems. Therefore, several studies in developing tools for linear regression models have brought interests from statisticians. One such problem is to find an efficient method for parameter estimation. Several different methods have been proposed in literature such as the ordinary least square method which has been widely used in application. However, the least square estimator has high error when there exists a multicollinearity problem. This, statisticians have developed alternative parameter estimation methods for linear regression models with multicollinearity such as the ridge regression. In this thesis, we …

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การจำลองอุทกพลศาสตร์ของหอฟื้นฟูสภาพตัวดูดซับสำหรับกระบวนการดักจับคาร์บอนไดออกไซด์ด้วยตัวดูดซับโพแทสเซียมคาร์บอนเนตบนตัวรองรับอลูมินาในเครื่องปฏิกรณ์ฟลูอิไดซ์เบดหมุนเวียน, ณัฐธิดา ภักดี Jan 2024

การจำลองอุทกพลศาสตร์ของหอฟื้นฟูสภาพตัวดูดซับสำหรับกระบวนการดักจับคาร์บอนไดออกไซด์ด้วยตัวดูดซับโพแทสเซียมคาร์บอนเนตบนตัวรองรับอลูมินาในเครื่องปฏิกรณ์ฟลูอิไดซ์เบดหมุนเวียน, ณัฐธิดา ภักดี

Chulalongkorn University Theses and Dissertations (Chula ETD)

ปัญหาการเปลี่ยนแปลงสภาพภูมิอากาศและปรากฏการณ์โลกร้อนจากการปล่อยแก๊สเรือนกระจก โดยเฉพาะแก๊สคาร์บอนไดออกไซด์ (CO₂) ที่เกิดจากการเผาไหม้เชื้อเพลิงฟอสซิลได้ทวีความรุนแรงขึ้น ส่งผลให้เทคโนโลยีดักจับและกักเก็บคาร์บอน (Carbon Capture and Storage, CCS) ได้รับความสนใจเพิ่มขึ้นเพื่อลดการปล่อยแก๊สคาร์บอนไดออกไซด์สู่ชั้นบรรยากาศ โดยเฉพาะกระบวนการดักจับแก๊สคาร์บอนไดออกไซด์หลังการเผาไหม้ (Post-combustion capture) งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาและพัฒนาแบบจำลองอุทกพลศาสตร์ของหอฟื้นฟูสภาพตัวดูดซับในระบบฟลูอิไดซ์เบดหมุนเวียน และวิเคราะห์ปัจจัยที่มีผลต่อประสิทธิภาพในการดักจับแก๊สคาร์บอนไดออกไซด์ และการฟื้นฟูตัวดูดซับ ขั้นตอนการวิจัยประกอบด้วยการจำลองกระบวนการด้วยแบบจำลองพลศาสตร์ของไหลเชิงคำนวณ (Computational Fluid Dynamics, CFD) โดยแบ่งการจำลองออกเป็นสองส่วน ได้แก่ การจำลองแบบไม่มีปฏิกิริยาเคมีเพื่อหาการเลือกแบบจำลอง Drag model ที่เหมาะสมสำหรับการจำลองอุทกพลศาสตร์ในไรเซอร์และดาวเนอร์ และการจำลองแบบมีปฏิกิริยาเคมีเพื่อวิเคราะห์ประสิทธิภาพในการดักจับแก๊สคาร์บอนไดออกไซด์ และการฟื้นฟูตัวดูดซับ รวมถึงการศึกษาผลของตัวแปรกระบวนการที่สำคัญ เช่น อุณหภูมิผนังดาวเนอร์ ความดันขาออกของดาวเนอร์ ปริมาณเบดเริ่มต้น และอัตราการไหลของตัวดูดซับ ผลการทดลองพบว่า การใช้แบบจำลอง Gidaspow ในไรเซอร์และดาวเนอร์ให้ผลการจำลองการไหลในระบบฟลูอิไดซ์เบดหมุนเวียนที่สอดคล้องกับข้อมูลเชิงทดลอง การปรับอุณหภูมิผนังดาวเนอร์จาก 473 เคลวินเป็น 573 เคลวิน ช่วยเพิ่มประสิทธิภาพการฟื้นฟูตัวดูดซับจาก 24.36% เป็น 31.02% แต่ลดประสิทธิภาพการดักจับแก๊สคาร์บอนไดออกไซด์ จาก 80.93% เป็น 78.11% นอกจากนี้ การลดความดันขาออกจาก 0 ปาสคาลเป็น -2000 ปาสคาล และการเพิ่มอัตราการป้อนกลับตัวดูดซับช่วยเพิ่มประสิทธิภาพของระบบอย่างมีนัยสำคัญ จากการศึกษาผลร่วมของตัวแปรกระบวนการ พบว่าปัจจัยที่สำคัญที่ส่งผลต่อประสิทธิภาพในการดักจับแก๊สคาร์บอนไดออกไซด์ และการฟื้นฟูตัวดูดซับ ได้แก่ อุณหภูมิผนังดาวเนอร์ ความดันขาออกของดาวเนอร์ ปริมาณเบดเริ่มต้น และอัตราการไหลของตัวดูดซับ การปรับค่าดังกล่าวในช่วงที่เหมาะสมสามารถช่วยเพิ่มประสิทธิภาพในการดักจับแก๊สคาร์บอนไดออกไซด์ และการฟื้นฟูตัวดูดซับได้อย่างมีประสิทธิภาพ

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Fixed Point And Periodic Cycle Of Sequence Arises From Number Of Factors, Thanapong Jaitrakoon Jan 2024

Fixed Point And Periodic Cycle Of Sequence Arises From Number Of Factors, Thanapong Jaitrakoon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Let. {an} and {bn} be sequences of positive integers. For each positive integer n., define an+1 to be the eube of the number of positive factors of an and define bn+1 to be the forth power of the number of positive factors of bn. This thesis proves that (i) if a1 > 1, then (an) eventually becomes the fixed point, namely 21952 or 64000, or {an}eventually becomes a sequence having periodie cycle of prime period 2, namely (64, 343) or (343, 64); (ii) if b1 > 1, then {bn} is eventually the fixed point, namely 625, 6561 or 4100625.

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Evaluating The Binding Modes Of Hepatitis B E-Antigen Inhibitor By In Silico Method, Wigrom Yogboworn Jan 2024

Evaluating The Binding Modes Of Hepatitis B E-Antigen Inhibitor By In Silico Method, Wigrom Yogboworn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Hepatitis B, caused by the hepatitis B virus (HBV), is a significant global health concern, primarily affecting the liver and leading to severe complications, including drug resistance and chronic infection. Numerous studies have linked these conditions to the presence of hepatitis B core antigen (HBcAg) and hepatitis B e antigen (HBeAg). HBeAg, in particular, is known to have the innate immune response, resulting in diminished immunity and delayed disease diagnosis and treatment. Despite this, the molecular structure and interactions between inhibitors and HBeAg remain poorly understood, posing a significant challenge to the development of effective treatments. This work employs molecular …

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Some Properties Of S-Multiplication Modules And S-Comultiplication Modules, Kanrop Hukaew Jan 2024

Some Properties Of S-Multiplication Modules And S-Comultiplication Modules, Kanrop Hukaew

Chulalongkorn University Theses and Dissertations (Chula ETD)

Let R be an associative ring with identity, and all modules be unitary right R- modules. In 2020, D. D. Anderson et al. introduced the concept of S-multiplication modules, which is a generalization of multiplication modules. Two years later, E. Yildiz et al. introduced the dual notion of S-multiplication modules called S- comultiplication modules. Moreover, S-comultiplication modules are also a gen- eralization of comultiplication modules. In this thesis, we will explore several properties of both S-multiplication modules and S-comultiplication modules. We will provide examples of S-multiplication modules and S-comultiplication modules. Additionally, we demonstrate that the concepts of S-multiplication modules, sim- …

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Metallopolymers For Photocatalytic Reduction Of Carbon Dioxide, Wissuta Boonta Jan 2024

Metallopolymers For Photocatalytic Reduction Of Carbon Dioxide, Wissuta Boonta

Chulalongkorn University Theses and Dissertations (Chula ETD)

CdS quantum dots (CdS QDs), acting as photosensitizers, or sometimes solo photocatalysts in CO2 reduction, have offered a myriad of advantages including quantum confinement effect, tunable redox potential, and photoreduction selectivity. However, CdS QDs are frequently compromised by thermal and oxidative instability, as well as photocorrosion, which restricts their practical applications. In this research, an effective method endowing CdS QDs by assembling with amphiphilic metallopolymer was developed to enhance their stability and synergistic activity. The thioglycolic acid-capped cadmium sulfide quantum dots (CdS) were successfully prepared using a simple reflux method. The amphiphilic metallopolymers were successfully synthesized via precise radical polymerization …

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การใช้เหมืองกระบวนการข้อมูลแบบหลายชั้นสำหรับเพื่อวิเคราะห์วิถีการรักษาพยาบาลของผู้ป่วยโรคเบาหวาน, Kantapat Chaichareenon Jan 2024

การใช้เหมืองกระบวนการข้อมูลแบบหลายชั้นสำหรับเพื่อวิเคราะห์วิถีการรักษาพยาบาลของผู้ป่วยโรคเบาหวาน, Kantapat Chaichareenon

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study addresses the challenge of chronic diseases like diabetes, requiring ongoing care. It aims to visualize revisit intervals affecting patient treatment using multi-level process mining and machine learning to identify factors causing missed appointments. Our research shows that patients with improvements have shorter revisit intervals than those deteriorating, with a P-value of 3.83x10%. A significant challenge is the high number of no-shows. Using PyCaret to compare 14 models, we found that the historical attendance of individual patients is a crucial factor in predicting no-shows, with an AUC score of 0.80 using the Gradient Boosting Clas-sifier. Our analysis suggests that …

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