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Full-Text Articles in Physical Sciences and Mathematics

Coordinating Multi-Party Vehicle Routing With Location Congestion Via Iterative Best Response, Waldy Joe, Hoong Chuin Lau Jan 2023

Coordinating Multi-Party Vehicle Routing With Location Congestion Via Iterative Best Response, Waldy Joe, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

This work is motivated by a real-world problem of coordinating B2B pickup-delivery operations to shopping malls involving multiple non-collaborative logistics service providers (LSPs) in a congested city where space is scarce. This problem can be categorized as a vehicle routing problem with pickup and delivery, time windows and location congestion with multiple LSPs (or ML-VRPLC in short), and we propose a scalable, decentralized, coordinated planning approach via iterative best response. We formulate the problem as a strategic game where each LSP is a self-interested agent but is willing to participate in a coordinated planning as long as there are sufficient …


Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek Jan 2023

Design Of An Internal Osculating Waverider Intake, Mark E. Noftz, Andrew J. Shuck, Joseph S. Jewell, Jonathan Poggie, Andrew N. Bustard, Thomas J. Juliano, Nicholas J. Bisek

Publications

The design of an inward-turning, high-speed, three-dimensional streamline traced intake is presented from osculating axisymmetric theory. To satisfy the osculating intake design criteria, a stitched Busemann diffuser and Internal Conical Flow-A solution is used as the basic isentropic compressive streamline. This new contour provides efficient compression, high flow uniformity, and straight leading edge shocks of equal strength. Additionally, a novel method for constructing the inlet cowl is presented. The combined process leads to a new method of high-speed intake design. A generic shape-transitioned intake is constructed and named the Indiana Inlet for the Indiana universities that contributed to the project. …


Estimating Potential Exposure From Abandoned Uranium Mine Sites Through Machine Learning Classification Of Animal Behavior: A Case Study In The Navajo Nation, Christopher Girlamo Jan 2023

Estimating Potential Exposure From Abandoned Uranium Mine Sites Through Machine Learning Classification Of Animal Behavior: A Case Study In The Navajo Nation, Christopher Girlamo

Geography ETDs

Waste from Abandoned Uranium Mines (AUMs) has negatively impacted Indigenous communities for generations. To answer these concerns, this research collaborated with Navajo Nation community members in Cove, AZ and Red Valley, AZ in order to better predict the potential AUM waste exposure their flocks face. A GIS-Multi-Criteria Decision Analysis (GIS-MCDA) model quantified potential exposure to AUM waste. Animal behavior was classified based on GPS and accelerometer data utilizing a Hidden Markov Model (HMM). The results of both the GIS-MCDA and animal behavior classification modeling was combined into a cumulative exposure potential value for each animal. This study found that livestock …


2-Uniform Covering Groups Of Elementary Abelian 2-Groups, Dana Saleh, Rachel Quinlan Jan 2023

2-Uniform Covering Groups Of Elementary Abelian 2-Groups, Dana Saleh, Rachel Quinlan

All Works

This article is concerned with the classification of Schur covering groups of the elementary abelian group of order (Formula presented.), up to isomorphism. We consider those covering groups possessing a generating set of n elements having only two distinct squares. We show that such groups may be represented by 2-vertex-colored and 2-edge-colored graphs of order n. We show that in most cases, the isomorphism type of the group is determined by that of the 2-colored graph, and we analyze the exceptions.


3d Indoor Modeling And Game Theory Based Navigation For Pre And Post Covid-19 Situation, Jaiteg Singh, Noopur Tyagi, Saravjeet Singh, Babar Shah, Farman Ali, Ahmad Ali Alzubi, Abdulrhman Alkhanifer Jan 2023

3d Indoor Modeling And Game Theory Based Navigation For Pre And Post Covid-19 Situation, Jaiteg Singh, Noopur Tyagi, Saravjeet Singh, Babar Shah, Farman Ali, Ahmad Ali Alzubi, Abdulrhman Alkhanifer

All Works

The COVID-19 pandemic has greatly affected human behavior, creating a need for individuals to be more cautious about health and safety protocols. People are becoming more aware of their surroundings and the importance of minimizing the risk of exposure to potential sources of infection. This shift in mindset is particularly important in indoor environments, especially hospitals, where there is a greater risk of virus transmission. The implementation of route planning in these areas, aimed at minimizing interaction and exposure, is crucial for positively influencing individual behavior. Accurate maps of buildings help provide location-based services, prepare for emergencies, and manage infrastructural …


Harvesting Publication Data To The Institutional Repository From Scopus, Web Of Science, Dimensions And Unpaywall Using A Custom R Script, Yrjo Lappalainen, Nikesh Narayanan Jan 2023

Harvesting Publication Data To The Institutional Repository From Scopus, Web Of Science, Dimensions And Unpaywall Using A Custom R Script, Yrjo Lappalainen, Nikesh Narayanan

All Works

Institutional repositories are established tools for archiving and increasing the visibility and availability of academic outputs. Although the potential benefits of institutional repositories are well researched and many funders and institutions already mandate open access publishing via gold or green open access routes, institutional repositories often struggle with lack of growth and sustained workflows for content recruitment. Institutions have come up with various (and often creative) workflows for populating their repositories, including institutional open access mandates, library-mediated self-archiving, fully or partially automated content harvesting and integrations between repositories and Current Research Information Systems (CRIS). Zayed University launched the ZU Scholars …


Forecasting Energy Consumption Demand Of Customers In Smart Grid Using Temporal Fusion Transformer (Tft), Amril Nazir, Abdul Khalique Shaikh, Abdul Salam Shah, Ashraf Khalil Jan 2023

Forecasting Energy Consumption Demand Of Customers In Smart Grid Using Temporal Fusion Transformer (Tft), Amril Nazir, Abdul Khalique Shaikh, Abdul Salam Shah, Ashraf Khalil

All Works

Energy consumption prediction has always remained a concern for researchers because of the rapid growth of the human population and customers joining smart grids network for smart home facilities. Recently, the spread of COVID-19 has dramatically increased energy consumption in the residential sector. Hence, it is essential to produce energy per the residential customers' requirements, improve economic efficiency, and reduce production costs. The previously published papers in the literature have considered the overall energy consumption prediction, making it difficult for production companies to produce energy per customers' future demand. Using the proposed study, production companies can accurately have energy per …


Of Stances, Themes, And Anomalies In Covid-19 Mask-Wearing Tweets, Jwen Fai Low, Benjamin C.M. Fung, Farkhund Iqbal, Ebrahim Bagheri Jan 2023

Of Stances, Themes, And Anomalies In Covid-19 Mask-Wearing Tweets, Jwen Fai Low, Benjamin C.M. Fung, Farkhund Iqbal, Ebrahim Bagheri

All Works

COVID-19 is an opportunity to study public acceptance of a ‘‘new’’ healthcare intervention, universal masking, which unlike vaccination, is mostly alien to the Anglosphere public despite being practiced in ages past. Using a collection of over two million tweets, we studied the ways in which proponents and opponents of masking vied for influence as well as the themes driving the discourse. Pro-mask tweets encouraging others to mask up dominated Twitter early in the pandemic though its continued dominance has been eroded by anti-mask tweets criticizing others for their masking behavior. Engagement, represented by the counts of likes, retweets, and replies, …


The Application Of Statistical Modeling To Identify Genetic Associations With Mild Traumatic Brain Injury Outcomes, Caroline Schott Jan 2023

The Application Of Statistical Modeling To Identify Genetic Associations With Mild Traumatic Brain Injury Outcomes, Caroline Schott

Masters Theses

"Traumatic brain injury (TBI) is a growing health concern, with millions of TBI diagnoses in the United States each year. The vast majority of TBI diagnoses are mild traumatic brain injuries (mTBI), which can be challenging to manage due to variation in symptoms and outcomes. Most individuals with mTBI successfully recover quickly, but a small subset has a delayed recovery. Although the factors that contribute to this variation in recovery are not clearly understood, it is possible that genetic differences may play a role. Very few studies have investigated the association between single nucleotide polymorphisms (SNPs) with mTBI outcomes and …


Computer Vision In Adverse Conditions: Small Objects, Low-Resoltuion Images, And Edge Deployment, Raja Sunkara Jan 2023

Computer Vision In Adverse Conditions: Small Objects, Low-Resoltuion Images, And Edge Deployment, Raja Sunkara

Masters Theses

"Computer vision based on deep learning is an essential field that plays a significant role in object detection, image classification, semantic segmentation, instance segmentation, and other applications. However, these models face significant challenges in adverse conditions, such as small objects, low-resolution images, and edge deployment. These challenges limit the accuracy and efficiency of computer vision algorithms, making it difficult to obtain reliable results.

The primary objective of this thesis is to assess the performance of deep learning- based computer vision models in challenging conditions and provide viable solutions to overcome the obstacles. The study will specifically address three key challenges, …


Characteristics And Color Varieties Of Spinels From Main Deposits, Boonyapak Aksorn Jan 2023

Characteristics And Color Varieties Of Spinels From Main Deposits, Boonyapak Aksorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

This study investigates the characteristics and color variations of spinels from main deposits, including Liolava in Madagascar, Tunduru in Tanzania, Mogok in Myanmar, and three deposits in Vietnam (Minh Tien, Lang Chap, and An Phu). These spinel samples are categorized into four color varieties, i.e., red, orange, blue, and purple. All samples yielded the common properties of spinels. In addition, most red and orange spinels display strong red fluorescence under long wave ultraviolet (LWUV) and short wave ultraviolet (SWUV) lamps, however, some orange spinels exhibit non-fluorescence to red fluorescence under SWUV lamps. Blue spinel displays non-fluorescence under LWUV and SWUV …


Development Of Electrochemical Biosensor For Detection Of Thyroid–Stimulating Hormone, Kittirat Kitticharoenwiwat Jan 2023

Development Of Electrochemical Biosensor For Detection Of Thyroid–Stimulating Hormone, Kittirat Kitticharoenwiwat

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation focused on the development of electrochemical paper-based immunosensor for determining thyroid-stimulating hormone (TSH) using a label-free immunoassay. Thyroid-stimulating hormone is a pituitary hormone that stimulates the thyroid gland to produce thyroid hormones for the body’s metabolism. The current electrochemiluminescence method for determining TSH as a specific biomarker indicating congenital hypothyroidism (CHT) onset is unfortunately restricted to laboratory settings, thereby resulting in limited practical utilization, delayed diagnosis, and severe outcomes. Herein, we proposed a simple, rapid, portable, and sensitive electrochemical biosensor with a label-free format based on bovine serum albumin (BSA)/graphene oxide (GO) nanocomposite for TSH determination. Caboxylated GO …


Bamboo Biochar For Bar Adsorptive Microextraction Of Parabens In Water, Maytinee Jantorn Jan 2023

Bamboo Biochar For Bar Adsorptive Microextraction Of Parabens In Water, Maytinee Jantorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, bamboo biochar bar was prepared in the form of small-sized rods using starch as a binder and applied as a sorbent in bar adsorptive microextraction (BAµE) of parabens (methyl paraben, ethyl paraben, propyl paraben and butyl paraben) in water. The mixture of bamboo biochar which has a size of 60-80 mesh, a surface area of 102.6 m²g-1 and a pore size of 0.7 nm and starch in a weight ratio of 1:13 gave the good mechanical stability and high removal efficiency of parabens. When applied the bamboo biochar bar as a sorbent, the optimum conditions for BAµE …


Selective Photodegradation Of Food Contaminants Using Titania-Silica-Iron Oxide Nanocomposites With Molecularly Imprinted Technology, Mehak Un Nisa Jan 2023

Selective Photodegradation Of Food Contaminants Using Titania-Silica-Iron Oxide Nanocomposites With Molecularly Imprinted Technology, Mehak Un Nisa

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this study, magnetic imprinted photocatalysts (Fe3O4@SiO2@TiO2@MIP and Fe3O4@SiO2@MIP@TiO2) have been synthesized successfully by surface molecular imprinting technique. 5,7-dimethoxy-coumarin was used as a dummy template to give specific recognition ability to AFB1. A range of analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), vibrating sample magnetometer (VSM), and Branauer-Emmett-Teller (BET) were employed to study the crystal structure, morphology, and chemical composition of the nanocomposites. The HPLC-DAD was used to quantify the photodegradation efficiency of imprinted photocatalysts under different factors such as the source of irradiation light, initial concentration of analyte, amount of photocatalyst, and …


Polyaniline/Cellulose Nanofiber/Polyvinyl Alcohol Hydrogel-Modified Screen-Printed Graphene Electrode For Cd2+ And Ni2+ Detection, Pichapon Boonkrong Jan 2023

Polyaniline/Cellulose Nanofiber/Polyvinyl Alcohol Hydrogel-Modified Screen-Printed Graphene Electrode For Cd2+ And Ni2+ Detection, Pichapon Boonkrong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Heavy metal contamination in wastewater has been an environmental issue, so the determination of heavy metals by an accurate and simple method is important. In this work, polyaniline/cellulose nanofiber/polyvinyl alcohol hydrogel-modified screen-printed graphene electrode (PANI/CNF/PVA hydrogel-modified SPGE) was fabricated by combining the advantages of graphene and conductive hydrogel to increase the conductivity and preconcentrate the metal ions to fabricate the modified electrode for the simultaneous detection of Cd2+ and Ni2+. First, PANI/CNF nanocomposite was synthesized by in situ chemical polymerization, and CNF was shown to prevented PANI aggregation and provided sufficient porous structure on the modified electrode. The PANI/CNF nanocomposite …


Carbon-Based Polymer Composite For Electrochemical Sensing Of Creatinine Sodium Potassium And Calcium Ions, Kanyapat Teekayupak Jan 2023

Carbon-Based Polymer Composite For Electrochemical Sensing Of Creatinine Sodium Potassium And Calcium Ions, Kanyapat Teekayupak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Electrochemical sensors have emerged as indispensable tools for various applications including environmental monitoring, food safety, and biomedical diagnostics owing to their simplicity, sensitivity, and fast response. However, traditional methods for electrode fabrication are often associated with drawbacks such as cleanroom requirements, multi-step processes involving toxic materials, high waste consumption, and high costs. To address the limitations, this dissertation evaluates the utilization of 3D printing, laser engraving, and inkjet printing technologies for the fabrication of electrochemical sensors based on carbon-based polymer composites. In the first part, a 3D-printed electrochemical sensor based on a copper oxide nanoparticle-ionic liquid/reduced graphene oxide (CuO-IL/rGO) modified …


Deep Reinforcement Learning For Electricity Energy Trading On Non-Sharing Information Scenario, Nat Uthayansuthi Jan 2023

Deep Reinforcement Learning For Electricity Energy Trading On Non-Sharing Information Scenario, Nat Uthayansuthi

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, we explore an optimized model for peer-to-peer (P2P) energy trading within microgrids that addresses the gap in previous research, which often assumed mandatory sharing of private information among prosumers. Our model-based multi-agent deep reinforcement learning framework includes several key components: an LSTM for the policy model, ; the Temporal Fusion Transformer (TFT) for predicting 24h-ahead net load consumption, adept at handling multivariate time series data; the inclusion of the Global Horizontal Index (GHI) to account for solar irradiance to the model; and a clustering technique to segment the dataset of 300 households from the Ausgrid dataset in …


Real-Time Polyp Analysis On Endoscopic Images Using Deep Learning Approach: Detection, Characterization And Size Estimation, Phanukorn Sunthornwetchapong Jan 2023

Real-Time Polyp Analysis On Endoscopic Images Using Deep Learning Approach: Detection, Characterization And Size Estimation, Phanukorn Sunthornwetchapong

Chulalongkorn University Theses and Dissertations (Chula ETD)

As medical devices advance, doctors adopt endoscopes to perform endoscopes for gastrointestinal disease screenings. For colonoscopy, skills such as polyp detection, polyp characterisation, and polyp size estimation needed to be practised while screening patients. This work aims to develop a deep learning model for performing polyp detection, characterisation, and size estimation to assist fellow doctors in these tasks. To maximise usability in assisting fellow doctors, the model must be able to perform in a real-time fashion. The work utilises existing object detection models for performing size estimation tasks. With the problems of data imbalances, we use depth information but without …


Application Of Machine Learning In Assessing Spatial Distribution Patterns Of Soil Microplastics: A Case Study Of The Bang Pakong Watershed, Thailand, Ugochukwu Ihezukwu Jan 2023

Application Of Machine Learning In Assessing Spatial Distribution Patterns Of Soil Microplastics: A Case Study Of The Bang Pakong Watershed, Thailand, Ugochukwu Ihezukwu

Chulalongkorn University Theses and Dissertations (Chula ETD)

Microplastics (MPs) are persistent environmental pollutants introduced through various factors. Understanding the spatial distribution characteristics of MPs is crucial for developing effective mitigation strategies. However, the relationship between MPs and their covariables remains largely unexplored. In this study, we investigated the abundance of MPs in 40 soil samples from different land-use types in the Bang Pakong Watershed and assessed the applicability of machine learning models for predicting the spatial distribution patterns of soil MPs. The samples were divided into three categories: 1.2 µm-500 µm, 500 µm-1 mm, and 1-2 mm. They were analyzed using ZnCl2 density separation, H2O2 digestion process, …


การพัฒนาตัวชี้วัดเพื่อประเมินคุณภาพพื้นที่สีเขียวในประเทศไทย, ธนโชค วานิชผดุงธรรม Jan 2023

การพัฒนาตัวชี้วัดเพื่อประเมินคุณภาพพื้นที่สีเขียวในประเทศไทย, ธนโชค วานิชผดุงธรรม

Chulalongkorn University Theses and Dissertations (Chula ETD)

การศึกษาในครั้งนี้มีวัตถุประสงค์เพื่อพัฒนาตัวชี้วัดสำหรับประเมินคุณภาพพื้นที่สีเขียวและทดสอบประสิทธิภาพการใช้งาน การศึกษาทำโดย 1) กำหนดวัตถุประสงค์การใช้งานตัวชี้วัดและผู้ที่มีส่วนเกี่ยวข้อง, 2) รวบรวมตัวชี้วัดที่เกี่ยวข้อง, 3) วิเคราะห์และเลือกตัวชี้วัดที่เหมาะสม, 4) จัดทำเป็นแบบประเมิน และ 5) ทดสอบกับพื้นที่สีเขียวตัวอย่างจำนวน 15 แห่ง ได้แก่ ป่าธรรมชาติ/ป่าชุมชน 3 แห่ง สวนสาธารณะ 4 แห่ง พื้นที่ส่วนบุคคล 5 แห่ง และหลังคาเขียว 3 แห่ง ผลการศึกษาได้ตัวชี้วัดคุณภาพพื้นที่สีเขียวแบ่งเป็น 4 ด้าน ได้แก่ สภาพแวดล้อม ความหลากหลายทางชีวภาพ บริการของระบบนิเวศ และการจัดการในพื้นที่ รวม 124 ตัวชี้วัด 370 คะแนน ผลการใช้ตัวชี้วัดพบว่าคะแนนคุณภาพพื้นที่สีเขียวอยู่ในช่วงระหว่าง 296-152 คะแนน ซึ่งเป็นผลจากวัตถุประสงค์การใช้งานและลักษณะพื้นที่ที่มีความหลากหลาย คะแนนแต่ละด้านของพื้นที่สีเขียวแต่ละประเภทส่วนใหญ่มีความสัมพันธ์กับลักษณะพื้นที่ การดูแลและการใช้งานของมนุษย์ ในส่วนของการใช้งานพบว่าผู้ใช้งานมีความพึงพอใจแบบประเมินที่สร้างขึ้นโดยภาพรวมในระดับปานกลางถึงดี (3.73 ± 1.08 คะแนน) โดยเป็นผลจากการออกแบบการประเมินในรูปแบบรวดเร็ว มีการอำนวยความสะดวกในการบันทึกข้อมูลในโปรแกรม Microsoft Excel ใช้เวลาและกำลังคนในการประเมินต่ำ แต่แบบประเมินยังต้องพัฒนาคำอธิบายรายละเอียดและขั้นตอนใช้งานรวมถึงเกณฑ์การให้คะแนนเพิ่มเติม นอกจากนี้ ควรเพิ่มจำนวนพื้นที่สีเขียวที่ประเมินให้มากขึ้นเพื่อทดสอบและปรับปรุงประสิทธิภาพตัวชี้วัด ตลอดจนส่งเสริมให้ผู้มีส่วนเกี่ยวข้องกลุ่มต่าง ๆ นำไปใช้ประโยชน์เพื่อพัฒนาคุณภาพพื้นที่สีเขียวของประเทศต่อไป


Efficiency And Functions Of Keystone Landfill Bacteria In Biodegradation Of Mixed Phthalate Esters, Adisan Rungsihiranrut Jan 2023

Efficiency And Functions Of Keystone Landfill Bacteria In Biodegradation Of Mixed Phthalate Esters, Adisan Rungsihiranrut

Chulalongkorn University Theses and Dissertations (Chula ETD)

Dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP), commonly used phthalate esters (PAEs), are persistent pollutants found in landfills due to the increasing accumulation of plastic waste. To develop an effective bioremediation tool, in this study, we explored the responses of indigenous bacterial communities in landfill waste covers to PAE contamination and identified and isolated the keystone species that play roles in PAE degradation to form PAE-degrading consortium. Microcosm experiments at room temperature (27-30°C) and 37°C showed rapid removal of 300 mg/kg DBP, with 95% removal in 14 days individually and 90% in 21 days as a mixture. DEHP at 300 …


Methyl Isobutyrate Production Via Hydrogenation Of Methyl Methacrylate Derived From Pyrolysis Of Acrylic Plastic Waste, Ramzi Nasser Ahmed Saif Jan 2023

Methyl Isobutyrate Production Via Hydrogenation Of Methyl Methacrylate Derived From Pyrolysis Of Acrylic Plastic Waste, Ramzi Nasser Ahmed Saif

Chulalongkorn University Theses and Dissertations (Chula ETD)

According to zero waste and upcycling policy, this work aims to utilize waste polymethyl methacrylate (PMMA) to methyl isobutyrate (MIB) via hydrogenation over nickel (Ni) based catalysts supported on commercial zeolites: HY, H-Beta-27 (SiO2/Al2O3 = 27 by mole), H-Beta-40 (SiO2/Al2O3 = 40 by mole) and H-ZSM-5. The appropriate catalyst support was first screen by using MMA monomer as the substrate for hydrogenation. Under 30 bar initial H2 pressure (PH2) at 250 °C for 3 h, Ni/H-Beta-27 catalyst effectively promoted hydrogenation to achieve 85% MMA conversion with 56.2 wt% MIB yield because of its larger external surface area and pore size. …


On Prime Labelings Of Uniform Cycle Snake Graphs, M. A. Ollis Jan 2023

On Prime Labelings Of Uniform Cycle Snake Graphs, M. A. Ollis

Emerson Authors, Researchers, & Creators

A reseaech paper in graph theory, a subfield of math. At the time of the research Agam Bedi and Samiksha Ramesh were undergraduate students at Emerson College and the work was completed as part of the SOC320 Research Co-Curricular in the summer of 2022. The work has a Creative Commons BY-NC licence.


การเปรียบเทียบการทำนายทิศทางของราคาหุ้นไทยโดยใช้ตัวแบบ Random Forests, Xgboost และ Lightgbm, สาธิตา ไชยมหา Jan 2023

การเปรียบเทียบการทำนายทิศทางของราคาหุ้นไทยโดยใช้ตัวแบบ Random Forests, Xgboost และ Lightgbm, สาธิตา ไชยมหา

Chulalongkorn University Theses and Dissertations (Chula ETD)

การศึกษานี้มีวัตถุประสงค์เพื่อทำนายทิศทางของหุ้นไทย โดยทำการทดลองเปรียบเทียบเครื่องมือทางสถิติด้วยตัวแบบ Random Forests, XGBoost และ LightGBM โดยใช้ตัวแปรค่าของข้อมูลก่อนหน้า (Lag Features) เพียงอย่างเดียว ข้อมูลตัวชี้วัด (Indicators) ของหุ้นเพียงอย่างเดียว และ ข้อมูลตัวชี้วัด (Indicators) ของหุ้นร่วมกับข้อมูลก่อนหน้า (Lag Features) กับทั้ง 3 ตัวแบบ ด้วยวิธีการปรับแต่งไฮเปอร์พารามิเตอร์ระหว่างการปรับให้เหมาะสมแบบเบย์ (Bayesian Search) และการค้นหาแบบสุ่ม (Random Search) ในการทำนายทิศทางหุ้นล่วงหน้า 1, 3, 5,10, 15, 30, 60, 90 และ 180 วัน โดยศึกษาหุ้นทั้งหมด 8 ตัวที่ต่างอุตสาหกรรม ดังนี้ เกษตรและอุตสาหกรรมอาหาร (AGRO) สินค้าอุปโภคบริโภค (CONSUMP) ธุรกิจการเงิน (FINCIAL) สินค้าอุตสาหกรรม (INDUS) อสังหาริมทรัพย์และก่อสร้าง (PROPCON) ทรัพยากร (RESOURC) บริการ (SERVICE) เทคโนโลยี (TECH) ข้อมูลราคาหุ้นจาก finance.yahoo.com ปี ค.ศ. 2014-2023 โดยเลือกหุ้นที่มีมูลค่าสูงสุดจากแต่ละกลุ่มอุตสาหกรรม ซึ่งขั้นตอนการแบ่งข้อมูลออกเป็นข้อมูลชุดฝึกฝน (Training Set) และข้อมูลชุดทดสอบ (Test Set) และทำการแบ่ง K-Fold Cross-Validation ทั้งหมด 5 Fold และวัดผลตัวแบบด้วยค่าความแม่นยำ (Accuracy), Precision, Recall, F1-Score และ AUC จากการศึกษาพบว่า ตัวแบบ Random Forests, XGBoost และ LightGBM มีผลลัพธ์การทำนายใกล้เคียงกันในแต่ละชุดตัวแปร และวิธีวิธีการปรับแต่งไฮเปอร์พารามิเตอร์ระหว่างการปรับให้เหมาะสมแบบเบย์ (Bayesian Search) และการค้นหาแบบสุ่ม (Random Search) ให้ผลลัพธ์ใกล้เคียงกันในแต่ละตัวแบบ …


การขจัดสีย้อมอินทรีย์ด้วยการดูดซับบนเมโซพอรัสซิลิกาโหลดด้วยโลหะ, อภิญญา ศิริพร Jan 2023

การขจัดสีย้อมอินทรีย์ด้วยการดูดซับบนเมโซพอรัสซิลิกาโหลดด้วยโลหะ, อภิญญา ศิริพร

Chulalongkorn University Theses and Dissertations (Chula ETD)

ความนิยมที่มากขึ้นในการใช้งานสีย้อมอินทรีย์ในอุตสาหกรรมสิ่งทอ จึงทำให้เกิดความกังวลเป็นอย่างมากเนื่องจากสีย้อมอินทรีย์เป็นอันตรายและก่อให้เกิดมลพิษทางน้ำ ความเป็นพิษของสีย้อมเหล่านี้ส่งผลเสียต่อระบบนิเวศ สีย้อมเหล่านี้มีความเสถียรมากเนื่องจากสีย้อมเหล่านี้ได้จากการสังเคราะห์และมีโครงสร้างโมเลกุลที่ซับซ้อน ดังนั้นงานวิจัยนี้จึงศึกษาการกำจัดสีย้อมที่ปนเปื้อนในน้ำโดยการดูดซับด้วยตัวดูดซับเมโซพอรัสซิลิกาและตัวดูดซับเมโซพอรัสซิลิกาที่โหลดด้วยโลหะ ตัวดูดซับเมโซพอรัสซิลิกาจะเตรียมโดยใช้วิธีแม่แบบชนิดอ่อน สีย้อมอินทรีย์ที่เลือกใช้ ได้แก่ สีย้อมเอซิดบลูซึ่งเป็นสีย้อมที่มีประจุลบ และสีย้อมเมทิลีนบลูซึ่งเป็นสีย้อมที่มีประจุบวก โดยมีการศึกษาผลของปัจจัยต่าง ๆ ที่มีต่อการดูดซับซึ่งจะรายงานผลในเทอมของร้อยละการกำจัดสีย้อม ลักษณะเฉพาะของตัวดูดซับสังเคราะห์จะวิเคราะห์ด้วยด้วยเทคนิคการเลี้ยวเบนของรังสีเอกซ์ การดูดซับการคายซับด้วยก๊าซไนโตรเจน เทคนิคฟูเรียร์ทรานส์ฟอร์มอินฟราเรดสเปกโตรสโคปี และ ผลรวมของประจุบนพื้นผิวตัวดูดซับเท่ากับศูนย์ จากผลการทดลองพบว่า ตัวดูดซับ 15Zn/MS600nc สามารถกำจัดสีย้อมเอซิดบลูได้ร้อยละ 100 เมื่อใช้ความเข้มข้นเริ่มต้นของสีย้อมเอซิดบลู 300 มิลลิกรัมต่อลิตร ความเป็นกรดด่างเท่ากับ 7 และปริมาณตัวดูดซับ 0.1 กรัม ภายในเวลา 15 นาที ตัวดูดซับ 15Zn/MS600c แสดงร้อยละการกำจัดสีย้อมสีเมทิลีนบลูที่ร้อยละ 94 เมื่อใช้ความเข้มข้นเริ่มต้นของสีย้อมเมทิลีนบลู 100 มิลลิกรัมต่อลิตร ความเป็นกรดด่างเท่ากับ 11 และปริมาณตัวดูดซับ 0.1 กรัม ภายในเวลา 15 นาที จากการศึกษาแบบจำลองจลนพลศาสตร์การดูดซับ พบว่า การดูดซับบนตัวดูดซับ 15Zn/MS600nc มีความสอดคล้องกับแบบจำลองของอาฟ์รามี โดยมีค่าสัมประสิทธิ์สหสัมพัทธ์เท่ากับ 0.9995 ในขณะที่ตัวดูดซับ 15Zn/MS600c เมื่อพิจารณาจากค่าสัมประสิทธิ์สหสัมพัทธ์ซึ่งมีค่าเท่ากับ 0.9695 จะมีความสอดคล้องกับแบบจำลองปฏิกิริยาอันดับสองเทียม


Effects Of Salix Psammophila On Groundwater Recharge In A Semiarid Area Of North China, Lizhu Hou, Jingdong Gao, Bill X. Hu, Xixi Wang Jan 2023

Effects Of Salix Psammophila On Groundwater Recharge In A Semiarid Area Of North China, Lizhu Hou, Jingdong Gao, Bill X. Hu, Xixi Wang

Civil & Environmental Engineering Faculty Publications

Study region: The semiarid Mu Us Sandy Land (MUSL) was selected for this study. It is in the farming-pastoral ecotone of north China and functions as an eco-environmental barrier.

Study focus: Afforestation can mitigate desertification and soil erosion by improving hydrologic condition, which is particularly true for semiarid and arid regions. However, little is known about the quantitative response of hydrologic improvement to afforestation level that can be measured by leaf area index (LAI). The objective was to setup and use a physically-based model to quantitatively assess the dynamics of water fluxes from Salix psammophila afforestation in the MUSL.

New …


Eeg-Based Spanish Language Proficiency Classification: An Eeg Power Spectrum And Cross-Spectrum Analysis, Blaise Xavier O'Mara, Skyler Baumer Jan 2023

Eeg-Based Spanish Language Proficiency Classification: An Eeg Power Spectrum And Cross-Spectrum Analysis, Blaise Xavier O'Mara, Skyler Baumer

Honors Theses and Capstones

Second language proficiency may be predicted with electrophysiological techniques. In a machine learning application, this electrophysiological data may be used for language instructors and language students to assess their language learning. This study identifies how electroencephalogram (EEG) power spectrum and cross spectrum data of the brain cortex relates to Spanish second language (L2) proficiency of 20 Spanish language students of varying proficiency levels at the University of New Hampshire. The two metrics for assessing cortical power and processing were event-related desynchronization (ERD)—a measure of relative change in power—of the alpha (8-12 Hz) brain frequency band, and alpha and beta (13-30Hz) …


Occurrence Of Per- And Polyfluoroalkyl Substances (Pfas) In New Hampshire Biosolids, Katherine A. Wieck Jan 2023

Occurrence Of Per- And Polyfluoroalkyl Substances (Pfas) In New Hampshire Biosolids, Katherine A. Wieck

Honors Theses and Capstones

Per- and polyfluoroalkyl substances (PFAS) are a group of over 4,000 compounds used in the manufacturing of products including aqueous film forming foams for firefighting, stain repellents, waterproofing agents, and nonstick cookware since their initial development in the 1940s. The long fluorinated carbon chain structure of PFAS causes chemical and thermal stability, and thus resistance to biodegradation. Biosolids produced at wastewater facilities for uses such as agricultural land-applied compost and fertilizer for lawns and athletic fields, as well as sludge disposed in landfills can cause contamination of groundwater and surface water. This poses a significant threat to human and environmental …


Determining Deuterium Polarization Via Nuclear Magnetic Resonance, Nicholas Muche Jan 2023

Determining Deuterium Polarization Via Nuclear Magnetic Resonance, Nicholas Muche

Honors Theses and Capstones

Dynamic Nuclear Polarization (DNP) is a method by which the spins of electrons are specifically targeted by microwaves at resonance frequency in order to induce spin flips. Occasionally, the electron spins couple with nuclear spins and nuclear spin flips are induced. The relaxation time of the electron is significantly lower than that of the nuclei, which allows for large polarization. The main goal of the Slifer Lab is to utilize specifically prepared crystalline structures in order to separate the convoluted energy transitions ("Batman Peak") in the deuterium's nuclear magnetic resonance (NMR) signal, which would allow for tensor enhancement of deuterium. …


Apt Adversarial Defence Mechanism For Industrial Iot Enabled Cyber-Physical System, Safdar Hussain Javed, Maaz Bin Ahmad, Muhammad Asif, Waseem Akram, Khalid Mahmood, Ashok Kumar Das, Sachin Shetty Jan 2023

Apt Adversarial Defence Mechanism For Industrial Iot Enabled Cyber-Physical System, Safdar Hussain Javed, Maaz Bin Ahmad, Muhammad Asif, Waseem Akram, Khalid Mahmood, Ashok Kumar Das, Sachin Shetty

VMASC Publications

The objective of Advanced Persistent Threat (APT) attacks is to exploit Cyber-Physical Systems (CPSs) in combination with the Industrial Internet of Things (I-IoT) by using fast attack methods. Machine learning (ML) techniques have shown potential in identifying APT attacks in autonomous and malware detection systems. However, detecting hidden APT attacks in the I-IoT-enabled CPS domain and achieving real-time accuracy in detection present significant challenges for these techniques. To overcome these issues, a new approach is suggested that is based on the Graph Attention Network (GAN), a multi-dimensional algorithm that captures behavioral features along with the relevant information that other methods …