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Effects Of Ball Milling Duration And Sintering Temperature On Mechanical Alloying Fe3si, Varistha Chobpattana, Chakansin Phoomkong, Peerawat Nutnual, Kritsada Thaengthong, Wanchai Pijitrojana

Journal of Metals, Materials and Minerals

Fe3Si is under interest as a ferromagnetic electrode of magnetic tunneling junctions (MTJs). Its crystalline structure is important for achieving high device efficiency. This work focuses on mechanical alloying of 3:1 ratio of 99% pure Fe and Si powder mixtures by ball milling and sintering. The mixtures were ball-milled for various durations up to 20 h. Then, they were sintered from 400°C  to 800°C for 4 h in Ar.  SEM images and particle size analysis show significant reduction in average particle size of the mixtures after ball milling for 20 h. The longer duration of ball milling process promotes powder …

Simulation-Based Assessment Of Operational And Retrofit Solutions For Effluent Compliance Of A Capacity-Limited Oxidation Ditch Wwtp, Ahmed Sameh Harash

Theses and Dissertations

Oxidation-ditch wastewater treatment plants (WWTPs) across Egypt's Nile Delta are increasingly carrying hydraulic and organic loads beyond what they were designed for. This work can be considered pioneering as this work compared operational and structural retrofit alternatives for such a plant within a single verified simulation framework. The present study fills that gap by building a digital twin of the Qaha WWTP, a dual-train Carrousel oxidation ditch in Qalyubia Governorate, calibrated to a baseline flow of 7,420 m³/day in the SUMO24 platform (a third-generation, open-source wastewater treatment process simulation software) using the SUMO2c biokinetic model (a simplified variant of Activated …

Sustainable – Low-Cost - Upgrade Of Activated Sludge Process For Nitrogen And Phosphorus (N&P) Removal From Wastewater, Abanoub N. Basta

Theses and Dissertations

Many municipal wastewater treatment plants (WWTPs) in developing countries were designed primarily for organic matter and suspended solids removal and therefore face increasing difficulty in meeting modern nitrogen (N) and phosphorus (P) discharge requirements. Conventional biological nutrient removal upgrades commonly require additional reactor volume, recirculation systems, aeration energy, and capital investment. Accordingly, sustainable retrofit strategies that improve nutrient removal within existing treatment footprints are increasingly needed, particularly in water-scarce and land-constrained regions.

This study investigated the integration of water hyacinth (Eichhornia crassipes) into the aeration stage of an activated sludge process as a hybrid nature-based enhancement for nitrogen and phosphorus …

A Comparative Study: Force Majeure And The Theory Of Unforeseen Circumstances Across Different Jurisdictions In The Middle East, Omar Hamed Sawan

Theses and Dissertations

The motivation behind this study stems from recent global disruption events that impact construction projects worldwide. These events vary across a wide spectrum, whether they are political events such as the Russo-Ukraine war or the war in the Middle East, economic events such as inflation or currency devaluations; or environmental events such as climate change and the emergence of public health crises like the Covid-19 pandemic. These series of events underscore the growing importance of understanding how the different legal frameworks address unforeseeable events in the construction industry. In this context, force majeure and the theory of unforeseen circumstances (also …

Enhancing Agricultural Sustainability Under Climate Change: A Multi-Scale Framework Integrating Climate Extremes, Resource Efficiency, And Data-Driven Modeling, Shahryar Fazli

Computational and Data Sciences (PhD) Dissertations

Agricultural systems are increasingly challenged by climate variability, where shifting temperature regimes, hydrological variability, and the rising frequency of compound and cascading extremes threaten global food security and resource sustainability. Addressing these challenges requires integrated frameworks that bridge biophysical monitoring, predictive modeling, and adaptive decision-making. This dissertation develops a data-driven, multi-scale framework to quantify and enhance agricultural resilience by integrating remote sensing, climate analytics, and machine learning across the United States, with a focus on California and the Western U.S.

First, hyperspectral and thermal remote sensing data from EMIT and OpenET are integrated to characterize crop nitrogen–water interactions and assess …

Green Waste Biochar And Plant Growth-Promoting Bacteria Enhance Tomato Growth Under Combined Nutrient Deficiency And Salinity Stress, Soumaya Tounsi-Hammami, Munawwar Ali Khan, Mahra Alqemzi, Salama Ali Almehairi, Aneesa Rasheed Anwar

All Works

This study characterized a green-waste-derived biochar from date palms and ghaf trees and investigated its potential as a soil amendment with halotolerant Bacillus spp. to improve tomato seedling quality under dual stress of salinity and nutrient deficiency. Biochar was produced through pyrolysis at 450 °C and then characterized for yield, pH, electrical conductivity, proximate analysis, surface morphology, energy-dispersive X-ray spectroscopy, and heavy-metal content. Its effectiveness was tested both alone and in combination with a Bacillus sp. mix, using a completely randomized design with varying NPK fertilizer levels and saline irrigation. Tomato seedlings were evaluated 45 days after planting for various …

Engineering Sulfur Concrete Mixes: A Data-Driven Approach To Aggregate Packing And Binder Efficiency, Vasilia Al Khaldi, Abdel Hamid I. Mourad, Maisa El Gamal

All Works

Processing window (mass loss < 3%). A first-order, order-of-magnitude carbon-footprint estimate—presented with explicit caveats rather than as a full life-cycle assessment—indicates that replacing Portland cement with by-product sulfur is the dominant contributor to a substantial reduction in embodied CO₂ per cubic metre relative to equivalent-strength Portland cement concrete. The valorization of steelmaking by-products aligns with circular economy principles, enabling high-performance, recyclable, and low-carbon construction materials without chemical binder modification.

Reimagining Sustainable Sulfur Concrete: A Systematic Review Of Sulfur, Waste Integration, And Durability, Vasilia Al Khaldi, Abdel Hamid I. Mourad, Maisa Elgamal

All Works

Sulfur concrete (SC) - a thermoplastic, waterless composite in which molten sulfur-based binder replaces Portland cement - is attracting growing research attention as a sustainable construction alternative capable of superior performance in chemically aggressive environments. This systematic literature review synthesises evidence from 127 sources (2000–2025), examining three interlinked dimensions: (i) the role of waste and industrial by-product materials as aggregate and filler substitutes; (ii) the influence of aggregate type, morphology, and grading on mechanical and microstructural performance; and (iii) durability under acid, saline, and freeze-thaw exposures. A transparent, PRISMA-aligned screening and classification protocol - here used as a structured review …

Comparative Performance Of Physiological Vital-Sign Forecasting Under Random And Patient-Wise Splitting Using Deep Learning, Lavanya Vasavi Chittem Reddy

Theses and Dissertations

Physiological vital-sign forecasting estimates future measurements based on recent temporal patterns and can support analysis of continuously recorded monitoring data. This study comparatively evaluated deep feedforward, recurrent, bidirectional recurrent, long short-term memory, and bidirectional long short-term memory architectures for one-step-ahead forecasting of peripheral oxygen saturation, heart rate, and pulse rate. Each model received consecutive observations of peripheral oxygen saturation, heart rate, pulse rate, respiratory rate, and age, while separate single-output models predicted the next value of the selected target.

Random and patient-wise data splitting were compared using identical input definitions, preprocessing procedures, model architectures, and training hyperparameters. The strongest architecture …

Mind The Hazard: Modeling And Interpreting Comfort With Personalized Sensing, Yufei Zhang, Matteo Favero, Patrick Chwalek, Sailin Zhong, Denis Lalanne, A. Joseph Paradiso, Clayton Miller, Andrew Sonta

Research Collection College of Integrative Studies

Recent advances in personalized sensing and comfort feedback have spurred the development of data-driven comfort models tailored to individual needs. However, because current models treat sequential comfort feedback independently, they are subject to unstable predictions and limited interpretability, hindering their deployment in building management. This study introduces a dynamic modeling framework that utilizes a Neural Ordinary Differential Equations-based Continuous-time Markov Chain to model the transitions in comfort states over time. Our modeling approach, developed through a field study utilizing smart glasses and mobile app feedback, tracks occupants' comfort transitions across daily activities and contexts. The results demonstrate that this model …

An Eco-Inspired Emulsion Membrane Harnessed With Waste Vegetable Oil For Effective Separation Of Ibuprofen: Insights Into Stability, Performance, And Kinetics, Huma Warsi Khan, A. Vijaya Bhaskar Reddy, Parvez Alam Khan, Samsur Akm Rahman, Muhammad Moniruzzaman

Publications and Research

Emulsion liquid membranes (ELMs) have emerged as excellent alternatives for the separation and recovery of biologically active drugs (BADs) from industrial waste at trace concentrations. Conventional ELMs generally utilize toxic petroleum-based solvents (PBS) that pose environmental and health risks. Although virgin vegetable oils have been appeared as sustainable alternatives to PBS, their widespread application is limited by economic constraints, resource sustainability, and competition with the food supply. In contrast, waste vegetable oil (WVO) represents an abundant, low-cost, and eco-friendly alternative, yet its potential as a green diluent for ELMs remains largely unexplored. To address this challenge, present study investigated the …

Ai-Driven Biomarker Discovery & Progression Modeling For Precision Diagnosis Of Glaucoma, Cheng Huang

Computer Science and Engineering Theses and Dissertations

This dissertation presents a comprehensive study on the integration of artificial intelligence (AI) for glaucoma diagnosis and retinal image analysis. Leveraging multimodal imaging data including fundus photography, Optical Coherence Tomography Optical Coherence Tomography (OCT) and Optical Coherence Tomography Angiography (OCTA), the research develops a suite of deep learning frameworks designed to detect early glaucomatous changes with high precision, robustness, and interpretability. A series of novel architectures are introduced, spanning vessel segmentation networks, biomarker discovery pipelines, and multimodal fusion models, all designed to enhance diagnostic accuracy and generalizability across diverse populations. To facilitate reproducible and scalable ophthalmic AI research, this work …

Decoding Surface Chemistry Effects On Polystyrene Nanoplastic Fouling In Plasma-Grafted Pes Membranes With Distinct Functional Groups, Mohadeseh Najafi, Javad Farahbakhsh, Ebrahim Mahmoudi, Michael Johns, Masoumeh Zargar

Research outputs 2022 to 2026

Nanoplastic (NP) fouling remains a key challenge for ultrafiltration (UF) membranes, yet systematic, controlled comparisons of how membrane functional groups govern NP-membrane interactions are still limited. Here, the role of membrane surface chemistry was systematically investigated using a controlled comparative framework based on plasma-grafted polyethersulfone (PES) UF membranes tailored with structurally comparable methacrylate monomers bearing distinct terminal functionalities, including mono-2-(methacryloyloxy)ethyl succinate (MMES, -COOH), N-[3-(dimethylamino)propyl] methacrylamide (DMAPMA, -N(CH3)2), and [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA, zwitterionic). Comprehensive characterisations supported successful surface grafting while preserving the membrane substructure. Fouling and separation were assessed using polystyrene (PS) NPs having different surface chemistries, i.e., PS, PS-COOH and …

Sensors And Smart Food Packaging For Supply Chains: Bridging Expiration Dates And Actual Perishability, Muhammad Umar Azam, Jolina Rodrigues, Mohamed Hamid Salim, Sarath Haridas Kaniyamparambil, Khalid Askar, Imane Belyamani, Blaise L. Tardy, Nouha Alcheikh

All Works

The food supply chain is undergoing critical changes to minimize environmental hazards, such as those associated with packaging, and reduce food waste and loss. One of the critical components of the latter is associated with the high variance in the perishability of individual foodstuffs. Herein, we review the state of the art in smart sensor systems and emphasize the critical role they could play in addressing the mismatch between “batch” based expiry dates and individual food products’ time-dependent responses to spoilage. Following a brief overview of food shelf life and associated legislation, a subsequent section summarizes the development of sensors …

Willingness To Pilot Under Varying Weather And Tower System Conditions: Mediating Effects Of Risk, Nathan Royal Schultz

Doctoral Dissertations and Master's Theses

The implementation of Remote Tower Systems (RTS) within the National Airspace System (NAS) offers potential improvements in operational efficiency, cost-effectiveness, and scalability; however, its success depends on pilots' willingness to operate in such environments. This study examined the effects of tower system type (RTS vs. Traditional Tower Systems [TTS]) and weather conditions (visual meteorological conditions [VMC], marginal visual meteorological conditions [MVMC], and instrument meteorological conditions [IMC]) on pilots’ willingness to pilot (WTP), while also evaluating the mediating role of perceived risk (PR). Grounded in Paul Slovic’s Risk Perception Theory (RPT), this research employed a quantitative experimental design using a factorial …

A Unified Pipeline For Network-Based Gene Pattern Discovery, Siddhartha Reddy Pullannagari, Sharlee Climer

Undergraduate Research Symposium

Large-scale genetic datasets from diverse diseases, including cancer and neurodegenerative disorders such as Alzheimer’s disease, provide unprecedented opportunities to study disease pathogenesis and generate hypotheses for drug discovery. However, identifying meaningful genetic interaction patterns within these datasets remains challenging due to combinatorial relationships amongst genes and heterogeneous biological underpinnings across subtypes. This project systematically analyzes a diverse collection of omics datasets (e.g., GSE44076, GSE97810, GSE127711, GSE112679) obtained from the NCBI Gene Expression Omnibus (GEO), spanning multiple biological conditions and data types. We use a unified computational pipeline designed to handle variation in dataset size, structure, and context. The steps in …

Biosensor Development In East Africa: A Systematic Review Of Technologies, Applications, Challenges, And Future Directions, Ally Mahadhy

Tanzania Journal of Science

Biosensors integrate biological recognition elements with signal transduction systems to generate quantitative or semi-quantitative analytical information and have applications across healthcare, food safety, agriculture, environmental monitoring, and wildlife health. Despite substantial global advances, biosensor development in East Africa remains poorly characterized. This systematic review, conducted according to PRISMA 2020 guidelines, evaluated published evidence from 1995 to 2025 within a predefined East African Community geographical scope. Eligibility was based on IUPAC-aligned operational criteria requiring an integrated biological recognition element, transduction mechanism, and quantitative or semi-quantitative signal output. Three locally developed biosensors met the criteria: an electrochemical nano-biosensor for schistosomiasis diagnosis in …

The Algorithmic Narcissus: Ai Validation And The Atrophy Of The 'Athletic' Social Self, Ilham Phalosa Reswara, Anggi Mayangsari

Jurnal Psikologi Sosial

Artificial intelligence systems designed around continuous affirmation and minimal friction are becoming increasingly prominent as social and relational partners in everyday life. This article examines how sustained interaction with such frictionless AI systems may reshape the developmental conditions under which social selfhood forms and is maintained. Drawing on Cooley's (1902) looking glass self, Kohut's (1971) concept of optimal frustration, and the developmental literature on social competence, the article argues that frictionless AI may distort the social mirror through which identity forms, remove the manageable frustration that appears necessary for psychological growth, weaken empathic capacity, and erode the social stakes that …

Improved Electromechanical Response And Relaxor Ferroelectric Behavior In (76–X)Bi₁/₂Na₁/₂Tio₃–24srtio₃ Ceramics Modified With Bifeo₃ And Bialo₃, Muhammadali K. Nigmatjanov, Farrukh B. Erkinov, Shoira A. Kadirniyazova

CHEMISTRY AND CHEMICAL ENGINEERING

Piezoelectric ceramics are smart functional materials capable of converting mechanical energy into electrical energy and vice versa, making them indispensable for modern sensors, transducers, and precision actuators. Historically dominated by lead-containing materials like Pb(Zr,Ti)O₃ (PZT), strict environmental regulations and health concerns have driven an urgent global shift toward eco-friendly alternatives. Currently, bismuth sodium titanate (Bi₁/₂Na₁/₂TiO₃–BNT)-based solid solutions are at the forefront of lead-free piezoceramic trends due to their excellent polarization and electromechanical coupling properties. In this study, lead-free piezoelectric ceramics based on the (76–x)Bi₁/₂Na₁/₂TiO₃–24SrTiO₃ (BNST24) system were synthesized, and their structural, dielectric, and electromechanical properties were systematically investigated. This study …

Chacahoula 2026, Volume 93, Pawan Khatri, Alayna Pellegrin

Chacahoula

The 2026 issue of Chacahoula, There's No Place Like Home, emphasizes the way in which our university becomes a home to students.  Featuring prize-winning poetry from Allyson Gee, Nick Fredrick, Amaris Kendall and Anmol Subedi, the book includes December 2025 and May 2026 graduating classes, as well as stunning photography of  campus life on the banks of Bayou Desiard. With features covering students, faculty, and staff, this year's time capsule preserves an academic year in the life of the University of Louisiana at Monroe. This edition includes a video message from President Carrie Castille. Download the PDF to your device …

Geotechnical Enhancement Of Noncohesive Coal Mine Overburden Using Microbially Induced Calcite Precipitation And Fly Ash Stabilization For Sustainable Pavement Applications, Atul Gautam, Laxmikant Yadu

Journal of Sustainable Mining

The majority of the waste generated from opencast mining, termed as overburden (OB), is dumped adjacent to the mine boundary and poses long-term stability issues. Various studies have been carried out to assess the risk of dump slope failure, and treatment strategies have been accordingly recommended to strengthen this OB dump. However, scant works are reported to sustainably utilize this OB for construction works. This study aims to quantify the performance of stabilized noncohesive coal mine OB collected from Gondegaon opencast mine (OCM) in India. Stabilization was achieved using two techniques, namely microbially induced calcite precipitation (MICP) through Sporosarcina pasteurii …

Scheduling The Charging Of Battery-Electric Vehicles Under Heterogeneous Scheduling Constraints, Justin Whitaker, Greg Droge, Mario Harper

Electrical and Computer Engineering Student Research

Adopting battery electric vehicles (EVs) for vehicle fleets requires scheduling charging alongside day-to-day operations. This problem is complicated by complex utility cost structures, limited battery capacity, and competition for shared charging resources. Existing methods that simultaneously schedule routes and charging neither address the full cost structure nor employ high-fidelity charging models, and no prior work analyzes fleets containing vehicles with heterogeneous routing constraints. This work addresses these gaps by combining a state-of-the-art flexible-schedule formulation with time-of-use (TOU) demand costs and a non-linear, variable-rate charging model as drawn from additional state-of-the-art works. The proposed method is validated against two state-of-the-art methods, …

Exploring Conceptions Of Engineering Design And Sustainability In Informal K–12 Engineering Education, Mobina Beheshti, Eunice Y. Kang, Avneet Hira

Journal of Pre-College Engineering Education Research (J-PEER)

In this study we investigate K–12 students’ conceptualizations of sustainability, their perspectives on the role of engineers in sustainable practices, and how augmented reality (AR) can facilitate sustainability-oriented engineering design activities in informal settings. The AR technology used in this study includes the Merge Cube (a physical cube that serves as a digital canvas for AR) and CoSpaces Edu (an online platform that allows students to create 3D models and animate them using code). We employ a design-based research methodology, using qualitative narrative and artifact analysis to address the research questions: (1) What are students’ conceptions of sustainability and the …

Modeling Urban Heat Island Mitigation Strategies In Egyptian Cities Using Envi-Met, Islam M. Gaber, Abbas M. Hassan, Tarek Elkashef, Ola A. Gad, Ahmed M. Abdo, Abdelrazek Elkomy

HBRC Journal

Mitigation techniques for urban heat islands (UHI) have emerged as a critical concern for global urban environmental sustainability. Passive cooling employing cool materials and/or urban greening has shown to be the most effective strategy for mitigating the impacts of UHI. This latter method, however, is relatively new in the literature of urban environmental studies, and research on it is still limited, particularly for cities in hot-dry climatic zones. This study aims to investigate the possibility of improving albedo rates and adopting urban greening measures, such as greening building roofs, roadways, and walkways, in several Egyptian cities located in various climatic …

Harnessing Nigeria’S Aquaculture And Fisheries Component Of The Blue Economy, B. S. Awe, O. Adeoti

Blue Economy

Nigeria aims to diversify from carbon to blue economy. Target 7 of Goal 14 of the United Nations 2030 Agenda for Sustainable Development, the creation of the Federal Ministry of Marine and Blue Economy, and the passage of the National Policy on Marine and Blue Economy (2025 -2034) in May 2025 are the three frameworks driving this ambition. However, water pollution and changes in climate are central to harnessing the aquaculture and fisheries component of the blue economy. With increasing waste disposal in waterways and waterbodies and decreasing river water flow due to changes in climate, these have implications for …

Safety And Resilience In Disaster Debris Removal And Clean-Up Operations: A Field And Training Guide For Resilience Workers In Disaster Debris Removal And Cleanup, Mohsen Shahandashti, Ph.D, P.E., Abhijit Roy, Ph.D, Zhe Yin, Ph.D, P.E., Pmp, Leed Ap, Antonio Balderrama, Ph.D, P.E., Sandesh Adhikari, Santosh Acharya

Mavs Open Press Open Educational Resources

A practical safety guide for the people who clear debris after disasters, and for the trainers who prepare them. Built for crews of every experience level--from seasoned operators to first-time volunteers--it teaches how to read a damaged site, recognize hidden and shifting hazards, work safely around heavy equipment and hazardous materials, and make sound decisions under pressure. Every chapter pairs clear guidance with a one-page field job aid, facilitator notes for trainers, and a real-world scenario, all grounded in OSHA, FEMA, EPA, and NIOSH guidance.

Safety and Resilience in Disaster Debris Removal and Clean-Up Operations Copyright © 2026 by Mohsen …

Integrated Fire Protection Design In Pharmaceutical Manufacturing Facilities: An Applied Case Study, Eman Osman Mahmoud Osman, Fouad Abdel-Mawgoud Abdel-Halim Qasim, Alaa El-Din El-Sayed Farid Hassan

HBRC Journal

The architectural design of pharmaceutical manufacturing facilities presents a complex engineering challenge, requiring simultaneous compliance with Good Manufacturing Practice (GMP) containment standards and life safety egress codes. This research presents an applied methodology for integrated fire protection design in sterile pharmaceutical environments, demonstrated through a case study of a manufacturing complex comprising cleanroom production zones and high-bay storage warehouses with heights reaching 14.8 m. The study reconciles facility classification under the Egyptian Fire Code and NFPA standards by defining Occupancy Hazard Groups W-1 and W-2 (high- and moderate-hazard storage), while utilizing regulatory Code Tables C-1 and C-2 to calculate occupant …

Semantic Shields: Automating Critical Infrastructure Defense Via Nlp-Driven Ransomware Profiling, Henry Trowbridge, Ian Zalcberg, Ryan Schley, Carter Yagemann, Natasha Phan, Srikar Maduposu, Vimal Buck

Military Cyber Affairs

Ransomware poses a growing threat to critical infrastructure, where successful attacks can disrupt operational technology (OT) and industrial control systems (ICS) with significant public safety consequences. However, attributing ransomware incidents to specific threat actors remains challenging due to ransomware-as-a-service ecosystems, actor rebranding, and the obfuscation of traditional indicators of compromise. This paper presents Semantic Shields, an NLP-driven attribution framework that leverages BERT-generated semantic embeddings and DBSCAN clustering to profile ransomware actors through the linguistic characteristics of ransom notes. Using a dataset of 295 ransom notes from 189 distinct threat groups, the framework achieved an 87.2% true positive clustering rate and …

Exploring The Role Of Single Pilot Operations In Night Cargo Aviation: A Phenomenological Study, Kollin Ellis

Doctoral Dissertations and Projects

The purpose of this qualitative descriptive phenomenology was to examine the lived experiences of pilots who have operated alone at night in an aviation cargo environment. The design was guided by an epistemological philosophical assumption. Extreme advancements in the technology of artificial intelligence and their applications in the aviation industry have raised the question of the value of a single operator serving in commercial cockpits. Some experts argue that a two-person crew is unnecessarily redundant. A significant gap in the current literature of experiential data existed to prompt this study. Through the contextual lens of the Dual Process Theory and …

Comparison Of Gravity Separation And Flotation For Pyrite Recovery From Tailings, Gülay Bulut, Gönül Göksu Gökçe, Dilruba Karamanlı, Oğuzhan Mert Gürkan, Ergin Sarp Zenzirci, Binnur Kırım, Alim Gül

Journal of Sustainable Mining

Tailings generated during the production of lead, zinc, and copper concentrates contain significant amounts of sulfide minerals, particularly pyrite. Pyrite, which remains in tailings after the recovery of other metals, is one of the main contributors to acid mine drainage (AMD). Therefore, recovering pyrite from tailings is environmentally and economically an important issue. In this study, pyrite recovery from tailings was investigated using flotation and gravity separation methods. Mineralogical characterization and liberation analyses were conducted by Mineral Liberation Analysis (MLA), indicating that pyrite is the major sulfide mineral with over 76% liberation degree even in the coarsest fractions. Flotation tests …