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Articles 67681 - 67710 of 294450
Full-Text Articles in Physical Sciences and Mathematics
ตัวกรองชีวภาพจุลสาหร่าย-แบคทีเรียที่มีชีวิตสําหรับการนํากลับสารอาหารทางการเกษตรจากน้ำเสียสังเคราะห์, ชลัมพล จันทร์พุ่ม
ตัวกรองชีวภาพจุลสาหร่าย-แบคทีเรียที่มีชีวิตสําหรับการนํากลับสารอาหารทางการเกษตรจากน้ำเสียสังเคราะห์, ชลัมพล จันทร์พุ่ม
Chulalongkorn University Theses and Dissertations (Chula ETD)
ปัจจุบันน้ำเสียกลายเป็นปัญหาใหญ่ที่ผู้คนต้องเผชิญในชีวิตประจำวัน แหล่งน้ำเสียประมาณ 70% มาจากน้ำเสียครัวเรือน ซึ่งมีสารประกอบไนโตรเจน (N) และฟอสฟอรัส (P) ที่มีความเข้มข้นสูง แต่กลับไม่ได้นำมาใช้ให้เกิดประโยชน์ งานวิจัยนี้จึงขอเสนอการพัฒนาตัวกรองชีวภาพที่มีชีวิตแบบจุลินทรีย์ผสมระหว่างจุลสาหร่ายและแบคทีเรียที่ส่งเสริมการเจริญเติบโตของพืชในการบำบัดน้ำเสียสังเคราะห์เพื่อศึกษาประสิทธิภาพในการกำจัดสารประกอบ N P และค่าความต้องการออกซิเจนทางเคมี (COD) จากน้ำเสียสังเคราะห์ระหว่างระบบแขวนลอยและตัวกรองชีวภาพที่มีชีวิต ตัวกรองชีวภาพที่มีชีวิตได้รับการพัฒนาโดยใช้เทคนิคการตรึงเซลล์ด้วยสารยึดเกาะบนพื้นผิวของผ้าฝ้ายที่ใช้เป็นวัสดุรองรับ จากการทดลองพบว่าสารยึดเกาะกัวร์กัม/คาราจีแนน (GG/CG) แสดงเปอร์เซ็นต์ความเสื่อมสภาพน้อยกว่า 5 % ซึ่งต่ำกว่าสารยึดเกาะอื่น ๆ และไม่เป็นพิษต่อเซลล์ หลังจากการบำบัดน้ำเสียสังเคราะห์เป็นเวลา 7 วัน พบว่าระบบตัวกรองชีวภาพที่มีชีวิตมีประสิทธิภาพการกำจัดสารอาหารและ COD สูงกว่าระบบแขวนลอย โดยเฉพาะอย่างยิ่งตัวกรองชีวภาพที่มีชีวิตในอัตราส่วนการผสม 3:1 ของจุลสาหร่าย Chlorella sp. และแบคทีเรีย Bacillus subtilis TISTR1415 ที่ตรึงด้วยสารยึดเกาะ GG/CG มีประสิทธิภาพในการกำจัด NH4+ PO43- และ COD สูงสุดมากถึง 91.81 % 99.44 % และ 83.15 % ในขณะที่ระบบแขวนลอยแสดงประสิทธิภาพในการกำจัดเพียงแค่ 56.75 % 58.71 % และ 69.57 % ตามลำดับ นอกจากนี้ ค่า pH ในระบบตัวกรองชีวภาพที่มีชีวิต (จาก 8.81 เหลือ 7.26) ลดลงมากกว่าระบบแขวนลอย (จาก 8.81 เหลือ 8.13)
การสังเคราะห์โพรเซสซิงออยล์ผ่านอิพ็อกซิเดชันของกรดไขมันเมทิลเอสเทอร์จากน้ำมันปาล์มสำหรับการผลิตยางวัลคาไนเซต, กฤติยา เพิ่มพิมพ์
การสังเคราะห์โพรเซสซิงออยล์ผ่านอิพ็อกซิเดชันของกรดไขมันเมทิลเอสเทอร์จากน้ำมันปาล์มสำหรับการผลิตยางวัลคาไนเซต, กฤติยา เพิ่มพิมพ์
Chulalongkorn University Theses and Dissertations (Chula ETD)
น้ำมันแอโรมาติกเป็นที่นิยมใช้ในน้ำมันสำหรับกระบวนการผลิตยางรถยนต์ อย่างไรก็ตามน้ำมันแอโรมาติกมีสารประกอบพอลิไซคลิกแอโรมาติกไฮโดรคาร์บอน (PAHs) ปริมาณมากที่ก่อให้เกิดเป็นสารก่อมะเร็งและส่งผลเสียต่อสิ่งแวดล้อม งานวิจัยนี้จึงมีวัตถุประสงค์เพื่อสังเคราะห์น้ำมันสำหรับกระบวนการผลิตยางจากปฏิกิริยาอิพ็อกซิเดชันของเมทิลเอสเทอร์ของกรดไขมันที่ได้จากน้ำมันปาล์มโดยใช้ตัวเร่งปฏิกิริยาวิวิธพันธุ์ ตัวเร่งปฏิกิริยาที่ใช้ในงานวิจัยนี้ ได้แก่ ไทเทเนียมไดออกไซด์ (TiO2-H) ซิลิกา (SiO2) และไททาเนียมซิลิคาไลต์ (TS-1-x) ที่สังเคราะห์จากวิธีไฮโดรเทอร์มัลโดย x คือ อัตราส่วนโดยโมลซิลิกาต่อไททาเนียมเป็น 40, 20 และ 10 ทั้งนี้ ได้มีการเปรียบเทียบกับตัวเร่งปฏิกิริยาไทเทเนียมไดออกไซด์ ชนิดอะนาเทส เกรดการค้า (TiO2-C) จากผลการวิจัยพบว่าตัวเร่งปฏิกิริยาที่ให้การเกิดปฏิกิริยาอิพ็อกซิเดชันกับ FAME ที่ได้จากน้ำมันปาล์มดีที่สุด คือ ตัวเร่งปฏิกิริยา TiO2-H โดยภาวะที่เหมาะสม คือ โดยใช้ปริมาณ 4 %โดยน้ำหนักของ FAME อุณหภูมิ 70 ๐ซ เป็นเวลา 24 ชม. พบว่าค่าการเปลี่ยนแปลง FAME 71% เกิดปริมาณออกซิเรน 1.84 % โดยน้ำหนัก และค่าการเปลี่ยนแปลงสัมพัทธ์ของออกซิเรน 67% อย่างไรก็ตาม พบว่าประสิทธิภาพตัวเร่งปฏิกิริยาเมื่อนำกลับมาใช้ใหม่ ค่าการเลือกเกิดของ FAME ปริมาณออกซิเรน และค่าการเปลี่ยนแปลงสัมพัทธ์ของวงออกซิเรนออกซิเจนมีแนวโน้มลดลงจากการใช้ตัวเร่งปฏิกิริยาเริ่มต้น นอกจากนี้ได้ศึกษาผลของการผสมน้ำมันอิพ็อกซิไดส์ของ FAME (epoxidize FAME, EFAME) ในยางธรรมชาติและยางไนไตรล์ต่อสมบัติการคงรูป สมบัติเชิงกล และการกระจายตัวของผงเขม่าดำ โดยเปรียบเทียบกับยางที่ผสมน้ำมัน TDAE (treated distillate aromatics extract) พบว่ายางทั้ง 2 ชนิดที่ผสมน้ำมัน EFAME มีสมบัติดีกว่ากับยางที่ผสมน้ำมัน TDAE
One-Pot Isothiocyanate Synthesis From Amines Using Hypervalent Iodines In Water, Rose Malina Annuur
One-Pot Isothiocyanate Synthesis From Amines Using Hypervalent Iodines In Water, Rose Malina Annuur
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, we have developed the mild and efficient desulfurization process in water such as 1) conversion of amine to isothiocyanate and 2) guanylation of thiourea into guanidine. For the first project, isothiocyanate was successfully synthesized from amine and carbon disulfide in the presence of cesium carbonate (Cs2CO3) and diacetoxyiodo benzene (DIB) as desulfurizing agent under 1 wt% TPGS-750-M/H2O. With optimized condition at room temperature in our hand, isothiocyanate derivatives were isolated by column chromatography in low to high yields (37-94%). Additionally, the aqueous medium can be recycled at least two cycles without significantly losing the yield of products. …
Beyond The Local Volume. I. Surface Densities Of Ultracool Dwarfs In Deep Hst/Wfc3 Parallel Fields, Christian Aganze, Adam J. Burgasser, Mathew Malkan, Christopher A. Theissen, Roberto A. Tejada Arevalo, Chih-Chun Hsu, Daniella C. Bardalez Gagliuffi, Russell E. Ryan Jr., Benne Holwerda
Beyond The Local Volume. I. Surface Densities Of Ultracool Dwarfs In Deep Hst/Wfc3 Parallel Fields, Christian Aganze, Adam J. Burgasser, Mathew Malkan, Christopher A. Theissen, Roberto A. Tejada Arevalo, Chih-Chun Hsu, Daniella C. Bardalez Gagliuffi, Russell E. Ryan Jr., Benne Holwerda
Faculty and Staff Scholarship
Ultracool dwarf stars and brown dwarfs provide a unique probe of large-scale Galactic structure and evolution; however, until recently spectroscopic samples of sufficient size, depth, and fidelity have been unavailable. Here, we present the identification of 164 M7-T9 ultracool dwarfs in 0.6 deg2 of deep, low-resolution, near-infrared spectroscopic data obtained with the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) instrument as part of the WFC3 Infrared Spectroscopic Parallel Survey and the 3D-HST survey. We describe the methodology by which we isolate ultracool dwarf candidates from over 200,000 spectra, and show that selection by machine-learning classification is superior to …
Online List Coloring For Signed Graphs, Melissa Tupper, Jacob A. White
Online List Coloring For Signed Graphs, Melissa Tupper, Jacob A. White
School of Mathematical & Statistical Sciences Faculty Publications
We generalize the notion of online list coloring to signed graphs. We define the online list chromatic number of a signed graph, and prove a generalization of Brooks’ Theorem. We also give necessary and sufficient conditions for a signed graph to be degree paintable, or degree choosable. Finally, we classify the 2-list-colorable and 2-list-paintable signed graphs.
Development Of A New Spe Uplc–Ms/Ms Method For Extraction And Quantitation Of Toluene Diamine On Gloves Following Toluene Diisocyanate Exposure, Asma Daoud, Pierre-Luc Cloutier, Sébastien Gagné, Livain Breau, Jacques Lesage
Development Of A New Spe Uplc–Ms/Ms Method For Extraction And Quantitation Of Toluene Diamine On Gloves Following Toluene Diisocyanate Exposure, Asma Daoud, Pierre-Luc Cloutier, Sébastien Gagné, Livain Breau, Jacques Lesage
Études primaires
Rationale
Toluene diisocyanate (TDI) is a highly reactive isocyanate commonly used as a mixture of 2,4- and 2,6- isomers in the production of flexible foams. Exposure to TDI occurs primarily through vapour inhalation in workplaces where TDI is produced or used, but dermal exposure is also possible during some tasks. To ensure workplace safety, accurate monitoring of TDI and toluene diamine (TDA) levels is required. Methods of quantifying field effectiveness of gloves in preventing dermal exposure have not been established. Therefore, there is a need to develop a new practical method for assessing glove effectiveness for TDI/TDA.
Method
A new …
Morphologic Clustering Of Earcanals Using Deep Learning Algorithm To Design Artificial Ears Dedicated To Earplugs Attenuation Measurement, Bastien Poissenot-Arrigoni, Chun Hong Law, Djamal Berbiche, Franck Sgard, Olivier Doutres
Morphologic Clustering Of Earcanals Using Deep Learning Algorithm To Design Artificial Ears Dedicated To Earplugs Attenuation Measurement, Bastien Poissenot-Arrigoni, Chun Hong Law, Djamal Berbiche, Franck Sgard, Olivier Doutres
Études primaires
Designing earplugs adapted for the widest number of earcanals requires acoustical test fixtures (ATFs) geometrically representative of the population. Most existing ATFs are equipped with unique sized straight cylindrical earcanals, considered representative of average human morphology, and are therefore unable to assess how earplugs can fit different earcanal morphologies. In this study, a methodology to cluster earcanals as a function of their morphologies with the objective of designing artificial ears dedicated to sound attenuation measurement is developed and applied to a sample of Canadian workers’ earcanals. The earcanal morphologic indicators that correlate with the attenuations of six models of commercial …
การสังเคราะห์และการอบฟิล์มบาง Vo2 ที่ปลูกด้วยกระบวนการโซลเจลเพื่อนำไปใช้เป็นกระจกกันความร้อนอัจฉริยะ, พงศธรณ พันธ์บูรณะ
การสังเคราะห์และการอบฟิล์มบาง Vo2 ที่ปลูกด้วยกระบวนการโซลเจลเพื่อนำไปใช้เป็นกระจกกันความร้อนอัจฉริยะ, พงศธรณ พันธ์บูรณะ
Chulalongkorn University Theses and Dissertations (Chula ETD)
ผู้ทดลองทำการทดลองเพื่อหาเงื่อนไขที่เหมาะสมสำหรับการปลูกฟิล์มบาง VO2 (M) ที่มีสมบัติ Semiconductor Metal transition (SMT) ซึ่งสามารถนำไปใช้ในการทดลองและใช้เป็นอุปกรณ์ต่างๆ เช่นกระจกกันความร้อนอัจฉริยะ (Smart Window) ผู้ทดลองปลูกฟิล์มบาง VO2 (M) ด้วยกระบวนการโซลเจลซึ่งเป็นวิธีที่มีความซับซ้อนไม่มากและค่าใช้จ่ายต่ำกว่าวิธีอื่น การทดลองนี้ศึกษาผลของตัวแปรทั้ง 5 ต่อการอบฟิล์มบาง VO2 ซึ่งตัวแปรทั้ง 5 ประกอบด้วย อุณหภูมิ เวลา บรรยากาศในขณะอบฟิล์ม ซับสเตรตและสารตั้งต้นที่ใช้ในการอบฟิล์ม ผู้ทดลองปลูกฟิล์มภายใต้อุณหภูมิต่างๆ (300, 400 และ 500 °C) และอบฟิล์มด้วยเวลาที่ต่างกัน (30, 60, 90 และ 120 นาที) ภายใต้บรรยากาศปกติและบรรยากาศที่มีออกซิเจนน้อย (ไนโตรเจนหรืออาร์กอน) การทดลองนี้ใช้ซับสเตรตสองชนิด (SiO2 และ Al2O3) และใช้สารตั้งต้นสองชนิด สารตั้งต้นชนิดแรกคือ VO(OC3H7)3 ที่มีอัตราส่วน V:O 1:4 และ เริ่มต้นด้วย V5+ สารตั้งต้นชนิดที่สองคือ VO(acac)2 ที่มีอัตราส่วน V:O 1:5 และ เริ่มต้นด้วย V4+ จากนั้นผู้ทดลองได้ตรวจสอบสมบัติและชนิดของฟิล์มด้วยการวัดความต้านทานที่อุณหภูมิต่างๆ ก่อนและหลังอบฟิล์ม ตรวจสอบโครงสร้างของฟิล์มโดยรามานสเปกโตรมิเตอร์และการวิเคราะห์การเลี้ยวเบนของรังสีเอกซ์ การทดลองให้ผลว่าอุณหภูมิที่สูงกว่าและเวลาที่นานกว่าในการอบทำให้ฟิล์มที่ได้มีสมบัติเข้าใกล้ VO2 (M) มากกว่าการใช้อุณหภูมิและเวลาในการอบที่น้อยกว่า นอกจากนั้นผู้ทดลองยังพบว่าเงื่อนไขที่เหมาะสมสำหรับการปลูกฟิล์มคือ การใช้ Al2O3 เป็นซับสเตรตโดยมี VO(OC3H7)3 เป็นสารตั้งต้นและทำการอบในบรรยากาศที่มีออกซิเจน น้อย ในการทดลองสุดท้ายผู้ทดลองปลูกฟิล์มบน Al2O3 โดยใช้ VO(OC3H7)3 เป็นสารตั้งต้นแล้วทำการอบที่อุณหภูมิ 500 °C นาน 120 นาที ภายใต้บรรยากาศที่มีออกซิเจนเป็นส่วนประกอบน้อย (อาร์กอน) ผลการวิเคราะห์การเลี้ยวเบนของรังสีเอกซ์และการใช้รามานสเปกโตรมิเตอร์ยืนยันว่าฟิล์มที่ได้เป็น VO2 (M) ที่ปนด้วย V6O13 ซึ่งมีสมบัติ SMT ที่ 79 °C และสามารถกั้นรังสีอินฟราเรดที่อุณหภูมิสูงได้เล็กน้อย …
Stability Of A Discrete-Time Infected-Aged Epidemic Model, Patchara Ploypetch
Stability Of A Discrete-Time Infected-Aged Epidemic Model, Patchara Ploypetch
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this thesis, we consider a discrete-time infected-aged SIS epidemic model. The model is obtained from a continuous-time SIS epidemic model by applying Micken’s nonstandard finite difference method. We derive some basic properties of solutions including the boundedness and positivity of solutions. Furthermore, we obtain two parameters R0 and R∞ so that if R0 < 1 then the infection becomes extinct whereas if R∞ > 1 the the infection becomes permanent.
Developing Test Statistics For Familial Dna Searches Through Classification Ideas, Chanagarn Laoiam
Developing Test Statistics For Familial Dna Searches Through Classification Ideas, Chanagarn Laoiam
Chulalongkorn University Theses and Dissertations (Chula ETD)
In a familial DNA search, the test statistic used for concluding a relationship is the likelihood ratio. In the traditional way, it is assumed that all individuals have the same genetic background ; however, population substructure typically exists and allele frequencies differ among subpopulations. To address this issue, a number of modified likelihood ratio statistics have been proposed. One is to apply the likelihood ratio framework to the average available allele frequencies (LRLAF). Another well-known three statistics are taking the maximum, minimum and average of all available likelihood ratios (LRMAX, LRMIN or LRAVG, respectively). In this thesis, two new likelihood …
Classification Of Metal Hydride Superconductors Using Machine Learning, Vichayuth Imchitr
Classification Of Metal Hydride Superconductors Using Machine Learning, Vichayuth Imchitr
Chulalongkorn University Theses and Dissertations (Chula ETD)
Metal hydrides are currently the main approach in the quest for high-temperature superconductors, as they exhibit a wide range of superconducting critical temperatures (TC). The key ingredient for determining the superconducting critical temperature is the phonon in the material. However, calculating the phonon via the first-principle method requires high computational costs and is time-consuming. To expedite the search for new superconducting hydrides, machine learning has been applied to scan for potential high-TC materials before performing phonon calculations. However, this method has limitations due to the limited number of available training samples, and the selection of input features for the task …
Thermodynamic Stability Prediction Of Multi-Transition-Metal Mxenes, Chayanon Atthapak
Thermodynamic Stability Prediction Of Multi-Transition-Metal Mxenes, Chayanon Atthapak
Chulalongkorn University Theses and Dissertations (Chula ETD)
Over the past decade, the largest group of two-dimensional alloys like transition metal carbides/nitrides (MXenes), have attracted a lot of attention in the material science community due to their alloying behaviors and their wide range of applications. However, the phase stability of multi-transition-metal MXenes has so far barely been validated. For this reason, examinations of the stability of multi-transition-metal MXenes from the theoretical aspect are highly of importance for future experimental synthesis and characterization of the materials. In this work, the proponent aims at investigating the thermodynamic stability of (Mo-Ti-V)3C2 MXenes, by performing computational simulations based on density functional theory …
Thermal Conductivity Studies Of Nitrogen Subsituted Single-Layered Diamond Using Density Functional Theory Simulation, Sakarn Khamkaeo
Thermal Conductivity Studies Of Nitrogen Subsituted Single-Layered Diamond Using Density Functional Theory Simulation, Sakarn Khamkaeo
Chulalongkorn University Theses and Dissertations (Chula ETD)
Recently, a promising two-dimensional material known as single-layered diamond or diamane has emerged, combining the interesting properties of bulk diamond with the exceptional thermal conductivity characteristic of two-dimensional materials. However, diamane’s stability requires high pressure unless its surfaces are passivated, for example, hydrogen or fluorine. Later, N-substituted diamane has been introduced as a solution, providing both stability and fascinating hardness properties. This thesis investigates the thermal properties of nitrogen-containing diamane using computational simulations with the density functional theory and the Boltzmann transport equation. The results show the out-of-plane vibration mode of N-substituted diamane, along with the calculated thermal conductivity with …
Synthesis And Biological Activities Of Acyl Derivatives Of Hydroxylated Eudesmanolides, Rawinnipha Wettayanugul
Synthesis And Biological Activities Of Acyl Derivatives Of Hydroxylated Eudesmanolides, Rawinnipha Wettayanugul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research focused on the synthesis of two hydroxylated eudesmanolides, reynosin (RNS, 2) and santamarine (STM, 3) from costunolide (1) isolated from Saussurea lappa roots, and the synthesis of their acyl derivatives to study on their biological activities. A total of 20 acyl derivatives of hydroxylated eudesmanolides, including 14 new compounds: 2(a-c), 3b, 3c, 3e, 3f, 3(h-j), and 3(l-o). The compounds were then evaluated for their anti-melanogenic, anti-colorectal cancer, and anti-inflammatory activities. It was observed that STM (3) exhibited anti-melanogenic and anti-colorectal cancer activity with IC50 values of 8.02 and 15.55 µM, respectively, which was greater than RNS (2) (IC50 …
Naturally Derived Polymeric Gel For Bio-Catalysis And Wound Dressing, Yuwaporn Pinyakit
Naturally Derived Polymeric Gel For Bio-Catalysis And Wound Dressing, Yuwaporn Pinyakit
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this thesis, two types of polymeric gels made from naturally derived polymers have been developed for bio-catalysis and wound dressing applications. In the first part, the heterogeneous biocatalyst with tunable geometry was fabricated using a 3D printing technique. The hydrogel-based ink as a supporting material for the immobilization of laccase was prepared from alginate (Alg) combined with Pluronic® F127-dimethacrylate (F127-DMA). Chemically crosslinked F127-DMA hydrogel with an optimized Alg composition exhibited good water swelling, mass transfer, and mechanical stability. To enhance the interaction between substrate and enzyme, the printed constructs with various surface-to-volume ratio (S/V) and geometrical designs (cubic, cylinder, …
Water Quality Prediction On Bang Pakong River Under Climate Change Using Data-Driven Models., Phuoc Thanh Ho
Water Quality Prediction On Bang Pakong River Under Climate Change Using Data-Driven Models., Phuoc Thanh Ho
Chulalongkorn University Theses and Dissertations (Chula ETD)
The Bang Pakong River, Chachoengsao Province, Thailand, is one of the most important rivers in the eastern part of Thailand due to its primary role in water supplies. However, the deterioration in the quality of the BPKR is critical due to anthropogenic activities and climate change since the 2000s. Therefore, the study aimed to establish ARMAX and MLP-ANN models to forecast some water quality parameters in the near future and predict general water quality indexes of the river, supported by correlation analysis between water quality parameters with climate and land use. The analysis results revealed that when agricultural land decreased …
Distributed Partial Differential Equation Solving With Julia Fast Fourier Transform Library, Christopher E. Mottola
Distributed Partial Differential Equation Solving With Julia Fast Fourier Transform Library, Christopher E. Mottola
Honors Theses and Capstones
Scientific computing relies on advanced computational and mathematical techniques to solve complex problems in scientific domains. For the numerical rendering of spectral, nonlinear, and dynamic phenomena, there is a growing need for greater availability of a broad class of Fourier-based algorithms to perform large scale operations on multidimensional data in distributed and optimized ways. To this effect, the Julia programming language is new and has significant advantages compared to other common languages used in scientific computing. The research presented here formulates a basis for further development in high-performance scientific computing of periodic partial differential equations through the application of distributed …
Investigating Signs Of Orbital Decay In The Tres-1 Exoplanetary System, Amanda F. Wester
Investigating Signs Of Orbital Decay In The Tres-1 Exoplanetary System, Amanda F. Wester
Honors Theses and Capstones
Transit observations of exoplanetary systems can be used to investigate orbital decay. TrES-1b is an exoplanet hypothesized to be experiencing orbital decay due to observed transit timing variations (TTVs) [12]. Numerous transits must be observed to establish a long term pattern to conclusively determine if the planet’s orbit is decaying. Measurements were made using the UNH Observatory where 2 transits were observed of the TrES-1b transiting system on February 27, 2022 and March 5, 2022. A CCD camera was used to image the transit and capture calibration images. The software AstroImageJ (AIJ) was used to calibrate the images and perform …
Harnessing The Power Of Interdisciplinary Research With Psychology-Informed Cyberbullying Detection Models, Deborah Hall, Yasin N. Silva, Brittany Wheeler, Lu Cheng, Katie Baumel
Harnessing The Power Of Interdisciplinary Research With Psychology-Informed Cyberbullying Detection Models, Deborah Hall, Yasin N. Silva, Brittany Wheeler, Lu Cheng, Katie Baumel
Computer Science: Faculty Publications and Other Works
Cyberbullying has become increasingly prevalent, particularly on social media. There has also been a steady rise in cyberbullying research across a range of disciplines. Much of the empirical work from computer science has focused on developing machine learning models for cyberbullying detection. Whereas machine learning cyberbullying detection models can be improved by drawing on psychological theories and perspectives, there is also tremendous potential for machine learning models to contribute to a better understanding of psychological aspects of cyberbullying. In this paper, we discuss how machine learning models can yield novel insights about the nature and defining characteristics of cyberbullying and …
Finding The Best Predictors For Foot Traffic In Us Seafood Restaurants, Isabel Paige Beaulieu
Finding The Best Predictors For Foot Traffic In Us Seafood Restaurants, Isabel Paige Beaulieu
Honors Theses and Capstones
COVID-19 caused state and nation-wide lockdowns, which altered human foot traffic, especially in restaurants. The seafood sector in particular suffered greatly as there was an increase in illegal fishing, it is made up of perishable goods, it is seasonal in some places, and imports and exports were slowed. Foot traffic data is useful for business owners to have to know how much to order, how many employees to schedule, etc. One issue is that the data is very expensive, hard to get, and not available until months after it is recorded. Our goal is to not only find covariates that …
Robot Guided Exercise Training: The Role Of The Human Model, Selena R. Richards
Robot Guided Exercise Training: The Role Of The Human Model, Selena R. Richards
Honors Theses and Capstones
Physical therapy after an injury can be difficult for patients to access, whether it be due to location, finances, or other factors. To make physical therapy more accessible, robot-guided exercise training can be used. Commercial anthropomorphic robots have been created and have human-like movement, but may still lack qualities that make it easy for a human to understand its intentions intuitively. A human model that mimics the movement of a robot performing human exercises can be used to complement the robot and increase human understanding. The ideal model would be viewable from different angles and could visibly show the difference …
A Review Of Monte Carlo Methods And Their Application In Medical Physics For Simulating Radiation Transport, Joe Shields
A Review Of Monte Carlo Methods And Their Application In Medical Physics For Simulating Radiation Transport, Joe Shields
Honors Theses and Capstones
Monte Carlo methods are used to calculate statistical behavior through the use of random number generators and probability density functions. They have been used extensively in medical physics for research in radiotherapy, designing technology, dosimetry, and advanced clinical applications. This paper provides a background on Monte Carlo methods and a review of radiation therapy physics and dosimetry. Additionally, there is a discussion of the different ways Monte Carlo methods are used in medical physics as well as a review of current research related to Monte Carlo methods. The final portion of this paper contains my own Monte Carlo simulation using …
Reinforcement Learning Applied To The Shoals Marine Laboratory Smart Grid, Daniel C. Mattson
Reinforcement Learning Applied To The Shoals Marine Laboratory Smart Grid, Daniel C. Mattson
Honors Theses and Capstones
Reinforcement learning (RL) techniques have been applied to smart grids with a variety of applications. The most common objective is to optimize profit for one actor in the system. The goal of this work is to apply different RL models to the smart grid at the Shoals Marine Laboratory (SML) located on Appledore Island, Maine in an effort to reduce costs and minimize the amount of nonrenewable energy consumed on the island. The RL models implemented resulted in more sustainable practices in simulations, with a linear spline model outperforming the naive policy the SML currently uses. Future work includes extending …
Generally Covariant Theory Of Multipole Moment Conserving Quasiparticles, Gavin Eric Riley
Generally Covariant Theory Of Multipole Moment Conserving Quasiparticles, Gavin Eric Riley
Honors Theses and Capstones
This report represents the creation of a field theory which is capable of describing quasiparticle excitations that preserve 2^k -pole moments. These quasiparticles exhibit certain ’semidynamic’ properties such as individual particle immobility but free movement of bound 2^L-tuples. We provide a review of work done on dipole conserving fractons and their dynamics [1] and expand upon it to describe higher moment conserving systems with global quadratic (and higher) phase symmetry. This requires the selection of the temporal and spatial directions. The selection of a temporal direction is done with a foliation defined by an anisotropic scaling of space and time, …
Development Of A Fluxgate Magnetometer Model, Eleonora Olsmats
Development Of A Fluxgate Magnetometer Model, Eleonora Olsmats
Honors Theses and Capstones
As a part of the UNH SWFO-L1 mission to monitor space weather and the sun’s behavior, the fluxgate magnetometer is an important component to measure external magnetic fields. The basic principle of a fluxgate magnetometer is to detect changes in the ambient magnetic field by inducing a magnetic field in a ferromagnetic material via a drive winding. Each magnetometer is unique due to the ferromagnetic properties of the core material which can be seen in the hysteresis loop which is a relationship between the magnetic field strength (H) and the induced magnetic field (B). Measuring the hysteresis of a fluxgate …
Future Climate Streamflow Estimation In The Donnelly River Catchment, Justin Hughes, Bill Wang
Future Climate Streamflow Estimation In The Donnelly River Catchment, Justin Hughes, Bill Wang
Natural resources commissioned reports
The Donnelly River is located in the south-west of Western Australia. An irrigation development has been proposed in the catchment that would extract water from the Donnelly River and store this in an off stream reservoir for irrigation use. Given the known issues related to non-stationarity and hydrological prediction, the Department of Primary Industries and Regional Development (DPIRD) contracted CSIRO to review the hydrological model that was used to estimate future climate streamflow in the Donnelly River. This model was owned and operated by the Department of Water and Environmental Regulation (DWER). The CSIRO review of the model, which also …
A Pilot Course As A Step Towards New Academic Programs In Renewable Energies, Otilia Popescu, Orlando Ayala, Isaac Flory, Jose Fernandez, Vukica Jovanović
A Pilot Course As A Step Towards New Academic Programs In Renewable Energies, Otilia Popescu, Orlando Ayala, Isaac Flory, Jose Fernandez, Vukica Jovanović
Engineering Technology Faculty Publications
The challenges arising from climate change have never before in human history been more pressing for solutions. Addressing pollution and the transition to clean energies are essential problems to solve in the upcoming decades. The process of transitioning to renewable energies has started already, with some states leading the process. As the development of industries sees a fast growth, the supply of qualified engineers and technicians to support these industries needs to keep up. At the community college level, some efforts have already started to introduce courses on renewable energies as well as boot camps or certifications to prepare the …
Framework For Sustainable Pastoral Management - Revised Edition, R Fletcher
Framework For Sustainable Pastoral Management - Revised Edition, R Fletcher
Natural resources published reports
This Framework for sustainable pastoral management, revised edition (the Framework) describes the contemporary risk-based approach that is now being used within Western Australia (WA) to ensure management of the State’s pastoral estate meets the principles of ecologically sustainable development (ESD). Development of the Framework was undertaken as part of the Pastoral Lands Reform project initiated by the WA Government in response to the Office of the Auditor General’s (OAG 2017) report, Management of pastoral lands in Western Australia. The Framework was developed by DPIRD with input from the Interagency Steering Committee (ISC – which included senior representatives of the WA …
Framework For Sustainable Pastoral Management - Land Condition Version, R Fletcher
Framework For Sustainable Pastoral Management - Land Condition Version, R Fletcher
Natural resources published reports
This document outlines the revised edition of the Framework for sustainable pastoral management, with a particular emphasis on the land condition components, including the monitoring, assessment and compliance processes. These processes are now being used to guide the management of land condition on all pastoral leases and stations within Western Australia (WA), which cover 860,000 km2 and represents over 40% of WA’s extensive rangeland area.
Status Of The Western Australian Pastoral Rangelands 2021, Department Of Primary Industries And Regional Development, Western Australia
Status Of The Western Australian Pastoral Rangelands 2021, Department Of Primary Industries And Regional Development, Western Australia
Natural resources published reports
This report updates the 2020 Rangelands annual report, the 2020 report outlines the condition, trend and risk of vegetation condition decline of pastoral rangelands in WA, based on the information available to September 2020. This 2021 report summaries the findings of the 2020 report and provides updated information on seasonal conditions in 2021 and stocking rates in 2020.
DPIRD produces a full report on the condition, trend and risk status of the WA pastoral rangelands every five years and provides updates on an annual basis. It is expected that the monitoring and assessment protocols used to generate future annual condition …