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Full-Text Articles in Physical Sciences and Mathematics

Understanding And Advancing College Students' Mathematical Reasoning Using Collaborative Argumentation, Rachel Kay Heili Jan 2023

Understanding And Advancing College Students' Mathematical Reasoning Using Collaborative Argumentation, Rachel Kay Heili

Graduate Theses/Dissertations

This study explored students’ mathematical reasoning skills and offered supports to advance them through a collaborative argumentation framework in a college intermediate algebra class. The goals of this study were to make observations about student reasoning, identify specific actions to address those observations, and document student growth in reasoning as a result of those actions. An iterative analysis, mixed method study was conducted in which the researcher engaged students in responding to questions that required conceptual understandings using a collaborative argumentation framework as a tool to identify and code components of their responses—claim, evidence, and reasoning. After coding and analyzing …


Structural And Magnetic Study Of Epitaxial Ni/Nio Thin Films On Various Single Crystalline Substrates Using Pulsed Laser Deposition, Md Shaihan Bin Iqbal Jan 2023

Structural And Magnetic Study Of Epitaxial Ni/Nio Thin Films On Various Single Crystalline Substrates Using Pulsed Laser Deposition, Md Shaihan Bin Iqbal

Graduate Theses/Dissertations

In recent years, magnetic thin films have gained significant attention in the field of spintronics, which is a branch of electronics that utilizes the spin of electrons in addition to their charge. The applications in the spintronic sector rely on the magnetic properties of the thin films. To address this, Ni (FM)/NiO (AFM) thin films on single crystalline sapphire and lithium niobate substrates have been investigated using pulsed laser deposition (PLD) technique prior to hydrogen-reduction annealing to explore new functionalities. The manufactured films were extensively analyzed by state-of-the-art characterization techniques. X-ray diffraction (XRD) and X-ray reflectometry (XRR) show the structural …


The Future Of Alternative Energy? Simulating Methyl Stearate Pyrolysis Via Molecular Dynamic Processes, Sarah J. Adeoye Jan 2023

The Future Of Alternative Energy? Simulating Methyl Stearate Pyrolysis Via Molecular Dynamic Processes, Sarah J. Adeoye

Graduate Theses/Dissertations

The process of extracting and refining crude oil is both expensive and environmentally hazardous. The synthesis of biodiesel sourced from vegetable oils is a renewable process and less hazardous to the environment. Therefore, we seek to understand the pyrolysis procedure at an atomic level in hopes of optimizing future fuel viability. Herein, I analyze methyl stearate (a component of biodiesel) using an in-house database of ab initio trajectories, each simulating 1.0 ps (with 1.0 fs resolution). These jobs were observed for significant bond-breaking/forming events, the type of fragments produced, and the exact position and time for each event. Statistical analysis …


On Covering Groups With Proper Subgroups, Collin B. Moore Jan 2023

On Covering Groups With Proper Subgroups, Collin B. Moore

Graduate Theses/Dissertations

In this paper, we explore groups that can be expressed as a union of proper subgroups. Using “covering number” to denote the minimal number of proper subgroups required to cover a group, we explore the nature of groups with covering numbers 3 and 4, while also finding covering numbers for p-groups, dihedral, and generalized dihedral groups.


Renewable Fuels: Molecular Dynamics Investigations Into Pyrolysis Of Methyl Linoleate, Elson Osakpolor Eguaosa Jan 2023

Renewable Fuels: Molecular Dynamics Investigations Into Pyrolysis Of Methyl Linoleate, Elson Osakpolor Eguaosa

Graduate Theses/Dissertations

With the rapid depletion of the world’s supply of fossil fuels, especially petroleum products, petroleum prices have risen by approximately 800% between the 1970s and now and are projected to continue rising. It is also expected that the world’s consumption of energy will increase commensurate with its growing population. Although biodiesel is a good renewable alternative, it has its limitations including high production costs and poor low-temperature performance. We seek to improve conventional biodiesel with pyrolysis to produce low molecular-weight compounds with high energy densities. Understanding the pyrolysis path on the atomic scale is key as it will allow us …


Geometric Dissections, Daniel Robert Martin Jan 2023

Geometric Dissections, Daniel Robert Martin

Graduate Theses/Dissertations

In the study of geometry, the notion of dissection and its mechanics are occasionally over-looked. We consider and trace the history and theorems surrounding geometric dissections in both recreational and academic mathematics. We explore the important advancements in this particular topic from antiquity through the nineteenth and early twentieth centuries. We conclude with an exploration of the Banach-Tarski paradox


Growth And Characterization Of Sm3hfbi5, Patrick Lambdin Jan 2023

Growth And Characterization Of Sm3hfbi5, Patrick Lambdin

Graduate Theses/Dissertations

First found experimentally in 2015, topological Weyl materials are desirable compounds that have garnered much interest due to their ability to conduct electricity via their surface states even though the bulk material is a semimetal. Such a candidate, Sm3HfBi5, was discovered with a flux crystal growth method, following an extensive amount of reaction syntheses. This thesis reports on the discovery, growth, structural characterization via x-ray diffraction, and magnetization measurements on Sm3HfBi5.


Bimee: Blockchain Based Incentive Mechanism Considering Endowment Effect, Jayanth Madupalli Jan 2023

Bimee: Blockchain Based Incentive Mechanism Considering Endowment Effect, Jayanth Madupalli

Graduate Theses/Dissertations

Crowdsensing, a paradigm in modern data collection, harnesses the collective power of mobile users equipped with sensory devices to contribute valuable data based on task-specific criteria. The efficacy of crowdsensing relies on sustained engagement from proficient users over extended periods. Incentivizing long-term participation is crucial, and blockchain technology emerges as a promising framework, providing a decentralized and immutable ledger. However, existing blockchain-based incentive mechanisms for crowdsensing encounter challenges. Firstly, they often overlook users' inherent bias towards loss aversion, a psychological phenomenon where individuals prioritize avoiding losses over acquiring equivalent rewards. Secondly, fairness issues arise, especially concerning newly participating users in …


Exploration And Synthesis Of Half-Heusler And Disordered Ternary Intermetallic Single Crystals, Md Fahel Bin Noor Jan 2023

Exploration And Synthesis Of Half-Heusler And Disordered Ternary Intermetallic Single Crystals, Md Fahel Bin Noor

Graduate Theses/Dissertations

Due to their distinct physical and chemical characteristics, half-Heusler compounds are intermetallic materials that have undergone substantial research. The general formula for these compounds is XYZ, where X and Y are transition metals and Z is a p-block element. Thermoelectricity is among the half-Heusler compounds' most exciting potential uses, but additional possible applications include spintronics, magnetic refrigeration, and superconductivity, among others. Recently, half-Heuslers (and Heuslers) have emerged as candidates for catalysts for hydrogenation. The CoNbSn half-Heusler compound, as well as another unique intermetallic ternary compound, the disordered Mn4-xCrxAl11, were successfully grown as single crystals …


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.


The Dynamic Relationship Between Permafrost And Landcover In Northwestern Canada’S Discontinuous Permafrost Zone, Olivia Carpino Jan 2023

The Dynamic Relationship Between Permafrost And Landcover In Northwestern Canada’S Discontinuous Permafrost Zone, Olivia Carpino

Theses and Dissertations (Comprehensive)

Northwestern Canada’s subarctic is among the most impacted regions in the world as it is experiencing rapid climatic and environmental change. As a result, northwestern Canada has been experiencing region-wide permafrost thaw and disappearance, both of which are also occurring at unprecedented rates. Permafrost temperatures in the Taiga Plains have been warming steadily over the last several decades, which has been particularly detrimental across its lower latitudes of the discontinuous permafrost zone where the permafrost is already relatively thin and warm. These factors indicate that permafrost in the southern Taiga Plains may be in a state of disequilibrium with the …


Equity In Focus : Investigating Gender Disparities In Glioblastoma Via Propensity Score Matching, Solomon Eshun Jan 2023

Equity In Focus : Investigating Gender Disparities In Glioblastoma Via Propensity Score Matching, Solomon Eshun

School of Mathematical & Statistical Sciences Faculty Publications

Gender disparities in health outcomes have garnered significant attention, prompting investigations into their underlying causes. Glioblastoma (GBM), a devastating and highly aggressive form of brain tumor, serves as a case for such inquiries. Despite the mounting evidence on gender disparities in GBM outcomes, investigations specific at the molecular level remain scarce and often limited by confounding biases in observational studies. In this study, I aimed to investigate the gender-related differences in GBM outcomes using propensity score matching (PSM) to control for potential confounding variables. The data used was accessed from the Cancer Genome Atlas (TCGA), encompassing factors such as gender, …


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 …


Blockchain And Puf-Based Secure Key Establishment Protocol For Cross-Domain Digital Twins In Industrial Internet Of Things Architecture, Khalid Mahmood, Salman Shamshad, Muhammad Asad Saleem, Rupak Kharel, Ashok Kumar Das, Sachin Shetty, Joel J. P. C. Rodrigues Jan 2023

Blockchain And Puf-Based Secure Key Establishment Protocol For Cross-Domain Digital Twins In Industrial Internet Of Things Architecture, Khalid Mahmood, Salman Shamshad, Muhammad Asad Saleem, Rupak Kharel, Ashok Kumar Das, Sachin Shetty, Joel J. P. C. Rodrigues

VMASC Publications

Introduction:: The Industrial Internet of Things (IIoT) is a technology that connects devices to collect data and conduct in-depth analysis to provide value-added services to industries. The integration of the physical and digital domains is crucial for unlocking the full potential of the IIoT, and digital twins can facilitate this integration by providing a virtual representation of real-world entities.

Objectives:: By combining digital twins with the IIoT, industries can simulate, predict, and control physical behaviors, enabling them to achieve broader value and support industry 4.0 and 5.0. Constituents of cooperative IIoT domains tend to interact and collaborate during their complicated …


24/7 Clean Energy, Todd Aagaard Jan 2023

24/7 Clean Energy, Todd Aagaard

University of Colorado Law Review

In the face of the rapidly escalating climate crisis, the electricity sector is moving toward renewable energy. To date, policies and strategies have focused on increasing overall renewable energy generation, with little regard for timing and location. The result has been a misalignment of supply and demand in renewable energy markets. Renewable power projects produce energy when and where it is least expensive, leaving supply scarce at other times and places. Consumers, meanwhile, continue to use power when and where they need it. This mismatch increases the electricity grid’s dependence on fossil fuel–fired electricity to meet electricity demand at times …


Pasture Condition Guides For The Southern Rangelands, Including The Gascoyne, Murchison And Goldfields-Nullarbor, Peter-Jon A. Waddell, Philip We Thomas, Wayne J. Fletcher, Kath Ryan, Joshua E. Foster, John K. Stretch, Jim S. Addison Jan 2023

Pasture Condition Guides For The Southern Rangelands, Including The Gascoyne, Murchison And Goldfields-Nullarbor, Peter-Jon A. Waddell, Philip We Thomas, Wayne J. Fletcher, Kath Ryan, Joshua E. Foster, John K. Stretch, Jim S. Addison

Bulletins 4000 -

These guides address a recognised gap in readily applicable and easily accessible information on southern rangelands pasture condition and management.

These guides provide descriptions and images for southern rangelands pastures with similar management requirements for the grazing of native pastures by livestock. Therefore, the focus is on palatability of vegetation to livestock, and the effects of livestock management and external factors on the condition of the vegetation and soils.

The first section provides an overview and map, introduces concepts and terms important to understanding arid shrubland management in general, these guides in particular, and includes an economic analysis of the …


Development Of Sensing And Programming Activities For Engineering Technology Pathways Using A Virtual Arduino Simulation Platform, Murat Kuzlu, Vukica Jovanovic, Otilia Popescu, Salih Sarp Jan 2023

Development Of Sensing And Programming Activities For Engineering Technology Pathways Using A Virtual Arduino Simulation Platform, Murat Kuzlu, Vukica Jovanovic, Otilia Popescu, Salih Sarp

Engineering Technology Faculty Publications

The Arduino platform has long been an efficient tool in teaching electrical engineering technology, electrical engineering, and computer science concepts in schools and universities and introducing new learners to programming and microcontrollers. Numerous Arduino projects are widely available through the open-source community, and they can help students to have hands-on experience in building circuits and programming electronics with a wide variety of topics that can make learning electrical prototyping fun. The educational fields of electrical engineering and electrical engineering technology need continuous updating to keep up with the continuous evolution of the computer system. Although the traditional Arduino platform has …