Engineering Commons^™

Experimental Assessment Of Thermal And Acoustics Interactions On Occupant Comfort In Mixed-Mode Buildings, Yuzhen Peng, Nogista Antanuri, Siu-Kit Lau, Bahador Jebelli, Kardinal Steve Jusuf, Clayton Miller, Ting Yi Teo, Xuan Yun Chua, Adrian Chong

Research Collection College of Integrative Studies

Mixed-mode buildings use natural ventilation (NV) through operable building envelopes (e.g., windows) and mechanical air-conditioning (AC) systems to condition indoor spaces with the goal of energy savings without compromising occupant comfort requirements. As a result, occupants within such buildings experience different thermal and acoustic conditions. In mixed-mode buildings, however, there is no clear guideline on assessing or predicting occupants’ thermal perception (e.g., thermal sensation and acceptability) and the interaction effects between thermal and acoustic comfort. This study investigates thermal and acoustic comfort as well as their interaction effects in mixed-mode buildings under NV and AC modes. A field study was …

Optimal Domain-Partitioning Algorithm For Real-Life Transportation Networks And Finite Element Meshes, Jimesh Bhagatji, Sharanabasaweshwara Asundi, Eric Thompson, Duc T. Nguyen

Civil & Environmental Engineering Faculty Publications

For large-scale engineering problems, it has been generally accepted that domain-partitioning algorithms are highly desirable for general-purpose finite element analysis (FEA). This paper presents a heuristic numerical algorithm that can efficiently partition any transportation network (or any finite element mesh) into a specified number of subdomains (usually depending on the number of parallel processors available on a computer), which will result in “minimising the total number of system BOUNDARY nodes” (as a primary criterion) and achieve “balancing work loads” amongst the subdomains (as a secondary criterion). The proposed seven-step heuristic algorithm (with enhancement features) is based on engineering common sense …

Vortex Particle Method For Electric Ducted Fan In Non-Axisymmetric Flow, Eduardo Alvarez, Cibin Joseph, Andrew Ning

Faculty Publications

The vortex particle method has been reformulated in recent work as a large eddy simulation (LES) in a scheme that is both meshless and numerically stable, solving long-standing issues of numerical stability. In this study, we build upon this meshless LES scheme to create a simulation framework for electric ducted fans. This poses the challenge of introducing solid boundaries in the vorticity form of the Navier-Stokes equations without a mesh. Rotor blades are introduced in our computational domain through an actuator line model (ALM) following well-established practices for LES. A novel, vorticity-based, actuator surface model (ASM) is developed for the …

Nonsolvent-Induced Phase Separation Inside Liquid Droplets, Rami Alhasan, Tanner A. Wilcoxson, Dakota S. Banks, Sion Jung, Douglas R. Tree

Faculty Publications

Nonsolvent-induced phase separation (NIPS) is a popular method for creating polymeric particles with internal microstructure, but many fundamental questions remain surrounding the kinetics of the complex coupled mass transfer and phase separation processes. In this work, we use simulations of a phase-field model to examine how (i) finite domain boundaries of a polymer droplet and (ii) solvent/nonsolvent miscibility affect the NIPS process. To isolate the effects of phase separation kinetics and solvent/nonsolvent mass transfer on the NIPS process, we study two different cases. First, we investigate droplet concentrations that originate inside the two-phase region, where phase separation kinetics alone governs …

An Engineering Approach For Evaluating The Lifetime Experience Of Sex Trafficking Victimization, Kimberly Starr Nagulpelli

Dissertations

This research is an original approach that applies industrial engineering and operations research tools to the sociological problem of sex trafficking victimization. Such an approach enables quantitative evaluation of the impacts on an individual’s lifetime by anti-trafficking efforts and public policies.

A fully interconnected, lifetime model for the experience of sex trafficking victimization is defined as the result of a comprehensive review of literature. Beginning with victimization risk, the defined model is an anticipatory tool to understand the incidences and consequences to individuals during their lifetime. This research develops the model further into a Discrete-Time Markov Chain (DTMC) with definitions …

Optimization Of Station-Skip In A Cyclic Express Subway Service, Jingfeng Yang, Hai Wang, Jiangang Jin

Research Collection School Of Computing and Information Systems

With rapid population growth and increasing demand for urban mobility, metropolitan areas such as Singapore, Tokyo, and Shanghai are increasingly dependent on public transport systems. Various strategies are proposed to improve the service quality and capacity of bus and subway systems. Express trains—i.e., trains that skip certain stations—are commonly used because they can travel at higher speeds, potentially reduce travel time, and serve more passengers. In this paper, we study cyclic express subway service (CESS), in which express trains provide routine transport service with cyclic (periodic) station-skip patterns that can be used in daily service. We propose an exact Mixed …

Performance Enhancement Of Photovoltaic-Thermal Modules Using A New Environmentally Friendly Paraffin Wax And Red Wine-Rgo/H2o Nanofluid, Hossein Nabi, Mosayeb Gholinia, Mehdi Khiadani, Abdellah Shafieian

Research outputs 2022 to 2026

Photovoltaic/thermal systems are one of the most efficient types of solar collectors because they absorb solar radiation and generate electricity and heat simultaneously. For the first time, this paper presents an investigation into the impact of red wine-rGO/H2O nanofluid and paraffin wax on the thermohydraulic properties of a photovoltaic/thermal system. The study focuses on three innovative nonlinear arrangements of the serpentine tubes. The effects of these materials and configurations are analyzed through numerical simulations. To improve the performance, environmentally friendly materials, including red wine-rGO/H2O nanofluid and paraffin wax, have been used. Various performative parameters such as electrical and thermal efficiency …

Enhanced Hardness-Toughness Balance Induced By Adaptive Adjustment Of The Matrix Microstructure In In Situ Composites, Mingjuan Zhao, Xiang Jiang, Yumeng Guan, Haichao Yang, Longzhi Zhao, Dejia Liu, Haitao Jiao, Meng Yu, Yanchuan Tang, Laichang Zhang

Research outputs 2022 to 2026

With the development of high-speed and heavy-haul railway transportation, the surface failure of rail turnouts has become increasingly severe due to insufficient high hardness-toughness combination. In this work, in situ bainite steel matrix composites with WC primary reinforcement were fabricated via direct laser deposition (DLD). With the increased primary reinforcement content, the adaptive adjustments of the matrix microstructure and in situ reinforcement were obtained at the same time. Furthermore, the dependence of the adaptive adjustment of the composite microstructure on the composites’ balance of hardness and impact toughness was evaluated. During DLD, the laser induces an interaction among the primary …

Elastic Buildings: Calibrated District-Scale Simulation Of Occupant-Flexible Campus Operation For Hybrid Work Optimization, Martín Mosteiro-Romero, Clayton Miller, Adrian Chong, Rudi Stouffs

Research Collection College of Integrative Studies

Before 2020, the way occupants utilized the built environment had been changing slowly towards scenarios in which occupants have more choice and flexibility in where and how they work. The global COVID-19 pandemic accelerated this phenomenon rapidly through lockdowns and hybrid work arrangements. Many occupants and employers are considering keeping some of these flexibility-based strategies due to their benefits and cost impacts.This paper explores how demand-driven control strategies in the built environment might support the transition to increased workplace flexibility by simulating various scenarios related to the operational technologies and policies of a real-world campus using a district-scale City Energy …

Saudi Arabian Basalt/Co2/Brine Wettability: Implications For Co2 Geo-Storage, Muhammad Ali, Nurudeen Yekeen, Amer Alanazi, Alireza Keshavarz, Stefan Iglauer, Thomas Finkbeiner, Hussein Hoteit

Research outputs 2022 to 2026

The geological sequestration of carbon dioxide, including mineralization in basaltic formations, has been identified as a promising method of attaining a low-carbon economy. However, successful CO₂ storage depends on both the CO₂ wettability of the basaltic rocks and the basalt rock-fluid interfacial interactions. The contact angles of brine/CO^₂ systems for Western Australian (WA) and Iceland basalts have been recently reported in the literature. However, contact angle datasets for evaluating the CO₂ wettability of Saudi Arabian (SA) basalt have not been previously reported. Moreover, there is limited information on the impact of organic acids on the wettability …

Geopolymers: The Green Alternative To Traditional Materials For Engineering Applications, Zahraa Jwaida, Anmar Dulaimi, Nuha Mashaan, Md A. O. Mydin

Research outputs 2022 to 2026

Researchers have been driven to investigate sustainable alternatives to cement production, such as geopolymers, due to the impact of global warming and climate change resulting from greenhouse gas emissions. Currently, they are exploring different methods and waste materials to enhance the mechanical and physical properties of geopolymer and expand its application range. This review paper offers a thorough analysis of the utilization of various waste materials in geopolymer manufacturing and shows the creative contribution of this research to the development of environmentally friendly cement substitutes. The article covers the properties, durability, and practical applications of geopolymer composites made from various …

Microstructural And Mechanical Behavior Investigations Of Nb-Reinforced Mg–Sn–Al–Zn–Mn Matrix Magnesium Composites, Ali Ercetin, Özgür Özgün, Kubilay Aslantaş, Oguzhan Der, Bekir Yalçın, Ercan Şimşir, Muhammad Aamir

Research outputs 2022 to 2026

This research focuses on the fabrication and characterization of TAZ532-xNb composites, employing high-purity, micron-sized powders of Mg, Sn, Al, Zn, Mn, and Nb as the raw materials. These powders were subjected to a paraffin coating process aimed at mitigating oxidation. The formation of composites was achieved via hot pressing and was followed by surface preparation and analysis using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). An X-ray diffraction (XRD) study was conducted to identify the microstructural phases. Quantitative assessments including the theoretical density, actual density, and relative density were computed, and their fluctuations in relation to the increasing Nb …

Patient Movement Monitoring Based On Imu And Deep Learning, Mohsen Sharifi Renani

Electronic Theses and Dissertations

Osteoarthritis (OA) is the leading cause of disability among the aging population in the United States and is frequently treated by replacing deteriorated joints with metal and plastic components. Developing better quantitative measures of movement quality to track patients longitudinally in their own homes would enable personalized treatment plans and hasten the advancement of promising new interventions. Wearable sensors and machine learning used to quantify patient movement could revolutionize the diagnosis and treatment of movement disorders. The purpose of this dissertation was to overcome technical challenges associated with the use of wearable sensors, specifically Inertial Measurement Units (IMUs), as a …

Influence Of Organics And Gas Mixing On Hydrogen/Brine And Methane/Brine Wettability Using Jordanian Oil Shale Rocks: Implications For Hydrogen Geological Storage, Amer Alanazi, Nurudeen Yekeen, Mujahid Ali, Muhammad Ali, Israa S. Abu-Mahfouz, Alireza Keshavarz, Stefan Iglauer, Hussein Hoteit

Research outputs 2022 to 2026

The substitution of fossil fuel with clean hydrogen (H₂) has been identified as a promising route to achieve net zero carbon emissions by this century. However, enough H₂ must be stored underground at an industrial scale to achieve this objective due to the low volumetric energy density of H₂. In underground H₂ storage, cushion gases, such as methane (CH₄), are required to maintain a safe operational formation pressure during the withdrawal or injection of H₂. The wetting characteristics of geological formations in the presence of H₂, cushion gas, …

Novel Approach For Non-Invasive Prediction Of Body Shape And Habitus, Emma Young

Electronic Theses and Dissertations

While marker-based motion capture remains the gold standard in measuring human movement, accuracy is influenced by soft-tissue artifacts, particularly for subjects with high body mass index (BMI) where markers are not placed close to the underlying bone. Obesity influences joint loads and motion patterns, and BMI may not be sufficient to capture the distribution of a subject’s weight or to differentiate differences between subjects. Subjects in need of a joint replacement are more likely to have mobility issues or pain, which prevents exercise. Obesity also increases the likelihood of needing a total joint replacement. Accurate movement data for subjects with …

Architectural Education And Targeted Skills An Evaluation Study Of Scientific Research Influence As Of Mechanisms Of Teaching And Learning, Heba Mahrous Ali

Mansoura Engineering Journal

The Engineering Study offers students an effective and technologically built education, considering the future prospects of science and technology. It also provides the technical knowledge and skills necessary to solve problems that allow future challenges to be addressed. Architecture is based on knowledge and skills in humanities, physics, humanities, and fine and applied arts. Therefore, what is taught about engineering subjects affects the extent of students' perception and this is evident in the extent of its interaction in the form of examinations or research. Scientific research is of great importance in he understanding of the student's understanding of scientific material. …

Neural Correlates Of Post-Traumatic Brain Injury (Tbi) Attention Deficits In Children, Meng Cao

Dissertations

Traumatic brain injury (TBI) in children is a major public health concern worldwide. Attention deficits are among the most common neurocognitive and behavioral consequences in children post-TBI which have significant negative impacts on their educational and social outcomes and compromise the quality of their lives. However, there is a paucity of evidence to guide the optimal treatment strategies of attention deficit related symptoms in children post-TBI due to the lack of understanding regarding its neurobiological substrate. Thus, it is critical to understand the neural mechanisms associated with TBI-induced attention deficits in children so that more refined and tailored strategies can …

Motion-Resistant Pulse Oximetry, Ludvik Alkhoury

Dissertations

The measurement of vital signs ? such as peripheral capillary oxygen saturation (SpO₂) and heart rate (HR) levels ? by a pulse oximeter is studied. The pulse oximeter is a non-invasive device that measures photoplethysmography (PPG) signals and extracts vital signs from them. However, the quality of the PPG signal measured by oximetry sensors is known to deteriorate in the presence of substantial human and sensor movements contributing to the measurement noise. Methods to suppress such noise from PPG signals measured by an oximeter and to calculate the associated vital signs with high accuracy even when the wearer …

Biomechanical And Psychophysical Underpinnings Of Balance Dysfunction In Individuals With Traumatic Brain Injury, Naphtaly Ehrenberg

Dissertations

Falls are a major burden on healthcare infrastructure, especially in older adults and even more so in older individuals that are living in institutions. According to data from the Centers for Disease Control and Prevention (CDC), from 2010 to 2020, unintentional falls were the leading cause of nonfatal emergency department visits for all age groups except among individuals from 15-24 years of age, where unintentional falls ranked a very close second to being unintentionally struck by or against. Among older individuals living in the community, approximately 30-35% fall at least once in a given year, and around three times as …

Sparse Methods For Blind Source Separation Of Frequency Hopping Rf Sources, Anushreya Ghosh

Dissertations

Blind source separation (BSS) is performed on frequency hopping (FH) sources. These radio frequency (RF) signals are observed by a uniform linear array (ULA) over a Spatial Channel Model (SCM) in four different propagation environments: (i) line-of-sight (LOS), (ii) single-cluster, (iii) multiple-cluster, and (iv) LOS with interference. The sources are spatially sparse, and their activity is intermittent and assumed to follow a hidden Markov model (HMM). BSS is achieved by utilizing direction of arrival (DOA) of the sources and clusters. A sparse detection framework is applied to obtain estimates of the sources' FH and DOA patterns. The solutions are binned …

Cu/Bnx Catalysts For Electrocatalytic Reduction Of Nitrogen And Nitrate Waste, Siming Huo

Dissertations

Ammonia (NH₃) is one of the most important chemicals to the whole human society. The invention of the Haber-Bosch process enabled the industrial production of NH₃. However, owing to the high capital costs of the centralized plant and the equipment and the negative environmental impact, it is no longer suitable for today's needs of human development. As a result, there is an urgent need to investigate sustainable approaches for ammonia production. Among those reported studies, nitrogen reduction (NRR) and nitrate reduction reaction (NO₃RR) are considered applicable in the future. However, after decades of studying …

Importance Of Vegetation In Tsunami Mitigation: Evidence From Large Eddy Simulations With Fluid-Structure Interactions, Abhishek Mukherjee

Dissertations

Communities worldwide are increasingly interested in nature-based solutions like coastal forests for the mitigation of coastal risks. Still, it remains unclear how much protective benefit vegetation provides, particularly in the limit of highly energetic flows after tsunami impact. The present thesis, using a three-dimensional incompressible computational fluid dynamics model with a fluid-structure interaction approach, aims to quantify how energy reflection and dissipation vary with different degrees of rigidity and vegetation density of a coastal forest.

In this study, tree trunks are represented as cylinders, and the elastic modulus of hardwood trees such as pine or oak is used to characterize …

Influence Of Material Properties On Granules Prepared By Dry Co-Rotating Twin Screw Extrusion And Counterrotating Batch Mixing, Afstathios Steve Pafiakis

Dissertations

Recently, the pharmaceutical industry has shown interest in continuous granulating technology because of the flexibility it offers as an option that bypasses the costly scale-up process associated with batch manufacturing. However, the granulation mechanism(s) using twin screw co-rotating hot melt extrusion (HME) has not been fully explored, and it is not yet well understood. This leads to costly experiments during development and process reliability problem in commercial manufacturing. The main objective of this dissertation is to increase the mechanistic understanding of the twin screw granulation process of systems containing an active pharmaceutical ingredient (API) and a polymer excipient. This is …

Pbm And Dem Simulations Of Large-Scale Closed-Circuit Continuous Ball Mill Of Cement Clinker, Nontawat Muanpaopong

Dissertations

Cement milling is known to be inefficient and energy-intensive. Thus, even small improvements in cement milling's performance could significantly reduce operation costs. This dissertation aims to develop a simulation tool for dry milling and generate a fundamental process understanding, which enables process optimization. To this end, a true unsteady-state simulator (TUSSIM) for continuous dry milling is developed and applied to model various processes: (a) open circuit continuous mills, (b) closed-circuit continuous mills, and (c) vertical roller mills. TUSSIM is based on the solution of the cell-based population balance model (PBM) for continuous milling, which consists of a set of differential …

Development Of Non-Viral Nano-Carriers For Gene Delivery And Covid-19 Vaccines, Zhongyu Li

Dissertations

Gene therapy is one of the most promising medical fields with the potential to effectively advance the treatment of difficult diseases by producing therapeutic proteins or repairing defective gene sequences. However, gene therapy presents severe challenges in delivery including renal clearance, phagocytosis, enzymatic degradation, protein absorption, and cellular internalization barriers, which have been barriers for translation into the clinic. Naked nucleic acids, with their intrinsic negative charge, electrostatically repulse the anionic cell membrane, preventing cellular uptake. Also, they are considered foreign genetic material when introduced into the body and are rapidly cleared by the reticuloendothelial system or degraded by nucleases, …

Development Of Novel Nanocarbon Based Materials And Membranes With Enhanced Biocidal Capabilities For Clean Water Generation, Indrani Gupta

Dissertations

Water scarcity is one of the major challenges facing humanity today, driven by population growth, economic development, and dietary shifts towards more water-intensive animal products. To address this issue, efficient water resource management and recycling of wastewater are essential. However, around 80% of wastewater globally is discharged into water bodies without treatment, posing a risk to ecosystems and human health. Pathogens, or harmful microorganisms, are a primary cause of water impairment and the transmission of waterborne diseases, leading to increased mortality rates. Traditional methods of treating pathogens involve the use of radiation or chemical disinfectants. Nonetheless, these methods have drawbacks, …

Neutrosophic Mcdm Methodology For Risk Assessment Of Autonomous Underwater Vehicles, Shimaa S. Mohamed, Ahmed Abdel-Monem, Alshaimaa A. Tantawy

Neutrosophic Systems with Applications

Due to its usefulness in several industries and the military, researchers have concentrated on developing autonomous underwater vehicles (AUVs). However, AUV navigation continues to be a difficult challenge to solve owing to the variety of underwater settings. The usage of AUVs, or autonomous underwater vehicles, is not without dangers like malfunction, ecological risks, loss of communications, cybersecurity risks, collisions, and others. There are many criteria to assess these risks technical, operational, economic, and regulatory. So, the methods of multi-criteria decision-making (MCDM) is used to deal with these various criteria. The analytical hierarchy process (AHP) method is an MCDM methodology, that …

Mathematical And Machine Learning Approaches For Classification Of Protein Secondary Structure Elements From Cα Coordinates, Ali Sekmen, Kamal Al Nasr, Bahadir Bilgin, Ahmet Bugra Koku, Christopher Jones

Computer Science Faculty Research

Determining Secondary Structure Elements (SSEs) for any protein is crucial as an intermediate step for experimental tertiary structure determination. SSEs are identified using popular tools such as DSSP and STRIDE. These tools use atomic information to locate hydrogen bonds to identify SSEs. When some spatial atomic details are missing, locating SSEs becomes a hinder. To address the problem, when some atomic information is missing, three approaches for classifying SSE types using Ca atoms in protein chains were developed: (1) a mathematical approach, (2) a deep learning approach, and (3) an ensemble of five machine learning models. The proposed methods were …

Compact Wideband Circularly-Polarised Slot Antenna For Ambient Rf Energy Harvesting, Khatereh Nadali, Jakub Przepiorowski, Neeraj Kumar Maurya, Patrick Mcevoy, Max Ammann

Conference papers

A dual-port dual-sense wideband circularly- polarised (CP) printed slot antenna is proposed. The compact coplanar waveguide (CPW)-fed antenna is proposed for ambient energy harvesting applications. Two identical CPW feeds excite ±45° fan-shaped stubs in the elliptical slot, providing a wide bandwidth. By separating the ground plane and slot by two narrow strips, an isolation better than 19.4 dB between the ports is achieved. The measured impedance bandwidth is 850 MHz (2.08 GHz to 2.93 GHz) and the 3dB axial-ratio bandwidth is 870 MHz (2.04 GHz to 2.91 GHz).

Characterization Of Low Power Hfo2 Based Switching Devices For In-Memory Computing, Aseel Zeinati

Theses

Oxide based Resistive Random Access Memory (RRAM) devices are investigated as one of the promising non-volatile memories to be used for in-memory computing that will replace the classical von Neumann architecture and reduce the power consumption. These applications required multilevel cell (MLC) characteristics that can be achieved in RRAM devices. One of the methods to achieve this analog switching behavior is by performing an optimized electrical pulse. The RRAM device structure is basically an insulator between two metals as metal-insulator-metal (MIM) structure. Where one of the primary challenges is to assign an RRAM stack with both low power consumption and …