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City University of New York (CUNY)

Dissertations and Theses

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Full-Text Articles in Engineering

Battery Energy Storage Systems Applications And Deployment In Dense Urban Areas, Mohamed K. Kamaludeen Jan 2023

Battery Energy Storage Systems Applications And Deployment In Dense Urban Areas, Mohamed K. Kamaludeen

Dissertations and Theses

Energy Storage has emerged as an important focus of the U.S. federal government, which has established the goal of developing global leadership in energy storage and has a near-term focus on strengthening the supply chain, manufacturing, and funding streams available to achieve the overarching objectives. At the state level, similar efforts are underway in which policy objectives have set aggressive targets around energy storage deployment. New York State, through its landmark climate act “CLCPA” and subsequent Energy Storage roadmap 2.0, has set one of the most aggressive goals in the Country targeting 6,000MW of energy storage by 2030. While much …


Understanding Failure Mechanisms Using Multi-Scale Analyses To Improve The Performance Of Zinc Metal And Lithium-Ion Batteries, Brendan E. Hawkins Jan 2023

Understanding Failure Mechanisms Using Multi-Scale Analyses To Improve The Performance Of Zinc Metal And Lithium-Ion Batteries, Brendan E. Hawkins

Dissertations and Theses

We are beginning a global transition away from the use of fossil fuels for our energy needs toward using renewable energy sources in order to mitigate the effects of climate change. One of the biggest challenges to this transition is that, unlike fossil fuels, renewable energy systems have inherent intermittency and require supporting energy storage systems to enable reliable power distribution and electrified transportation. Rechargeable batteries are an attractive energy storage option because of their high energy efficiency, versatility, modularity, and ease of use. Lithium-ion batteries (LIBs) have dominated the rechargeable battery market for portable electronics for the past two …


Ultra-High Field Mri Methods For Precise Anatomical And Spectroscopic Measurements In The Brain And Application To Neurological And Neuropsychiatric Diseases, Judy Alper Jan 2023

Ultra-High Field Mri Methods For Precise Anatomical And Spectroscopic Measurements In The Brain And Application To Neurological And Neuropsychiatric Diseases, Judy Alper

Dissertations and Theses

Neurological and neuropsychiatric diseases and disorders are a major burden on society, impairing the health and functioning of millions of people every year. There is a need to define the biological bases of these diseases and identify potential biomarkers to improve diagnosis, monitoring, and treatment efficacy across multiple diseases.

Magnetic resonance imaging (MRI) is a noninvasive imaging technique which facilitates detection of brain lesions and visualization of the brain overall. However, limitations in contrast and resolution at clinical field strengths may hinder investigation of the underlying biological mechanisms of these diseases. Ultra-high field MRI scanners, such as those at 7-Tesla, …


Measurement Of Fluid Movement Throughout The Brain Via Multiple Magnetic Resonance Imaging Techniques During High-Definition Transcranial Direct Current Stimulation, Jack W. Beaty Mr Jan 2023

Measurement Of Fluid Movement Throughout The Brain Via Multiple Magnetic Resonance Imaging Techniques During High-Definition Transcranial Direct Current Stimulation, Jack W. Beaty Mr

Dissertations and Theses

Transcranial Direct Current Stimulation (tDCS) is a non-invasive method of neuromodulation with applications in neuroscience, clinical care, and biomedical engineering. tDCS has been well established as a safe method of applying low amplitude current between two or more electrodes to alter excitation thresholds and neuroplasticity. Recently, in-vitro and clinical studies have suggested that DC stimulation can induce a transient, polarity-specific, effect of increased water exchange across the blood-brain barrier (BBB). The electroosmotic effect, the proposed phenomenon driving water exchange, is a biophysical response of charged ions moving across an oppositely-charged surface, i.e., the tight junction, when subjected to an electric …


Modulation Of Brain Tissue Transport And Endothelial Glycocalyx And Tight Junctions Of The Blood-Brain Barrier By Transcranial Direct Current Stimulation, Yifan Xia Jan 2022

Modulation Of Brain Tissue Transport And Endothelial Glycocalyx And Tight Junctions Of The Blood-Brain Barrier By Transcranial Direct Current Stimulation, Yifan Xia

Dissertations and Theses

Transcranial direct current stimulation (tDCS) is a non-invasive approach to treat a broad range of brain disorders and to enhance memory and cognition in healthy individuals. In addition to directly acting on neurons by modulating the membrane potential, inducing neuronal polarization and changing cortical excitability in the brain to achieve its therapeutic effects, prior studies found that tDCS can transiently enhance the permeability (P) of the blood-brain barrier (BBB), the interface between blood circulation and brain tissue. Brain extracellular space (ECS) is a narrow microenvironment which surrounds every cell in the central nervous system (CNS). ECS occupies ~20% of brain …


The Capabilities And Limitations Of Flywheel-Based Energy Storage System Pertaining To Subways In The Event Of A Power Outage, Jaskaran Singh Jan 2022

The Capabilities And Limitations Of Flywheel-Based Energy Storage System Pertaining To Subways In The Event Of A Power Outage, Jaskaran Singh

Dissertations and Theses

In the city that never sleeps, power outages or blackouts can be a shock, especially if you are on a train amid one. For example, during the infamous 2003 blackout, thousands of people were left stuck and stranded in parts of Northeastern United States. In particular, with no trains or buses in service throughout the 5 boroughs of NYC, those stranded essentially had no way to go back home. Hotels, terminals, and airports alike became places of camping as the city seemed to come to a halt. For the sake of public safety and transit efficiency, this study explores a …


Towards Simulation Of Complex Ocean Flows: Analysis And Algorithm For Computation Of Coupled Partial Differential Equations, Wenbin Dong Jan 2022

Towards Simulation Of Complex Ocean Flows: Analysis And Algorithm For Computation Of Coupled Partial Differential Equations, Wenbin Dong

Dissertations and Theses

The hybrid CFD models which usually consist of 2 sub-models, develop our capability to simulate many emerging problems with multiphysics and multiscale flows, especially for the coastal ocean flows interacted with local phenomena of interest. For most cases, the sub-models are connected with direct interpolation which is easy and workable. It becomes urgently needed to investigate the inner mechanism of such model integration as this simple method does not work well if the two sub-models are different in governing equations, numerical methods, and computational grids. Also, it can not treat complex flow structures as well as the balance in mass …


Towards An Artificial Intelligence Based Decision Support System To Evaluate Various Transit Projects, Patricio F. Vicuna Jan 2022

Towards An Artificial Intelligence Based Decision Support System To Evaluate Various Transit Projects, Patricio F. Vicuna

Dissertations and Theses

This dissertation addressed a subset of the Transit Network Design Problem (Transit-NDP), where the main evaluation parameter is the impact of various transit projects – Bus Lines, Tram, Light Rail, Rail – on the Network Travel Time (NTT) of the vehicles. The NTT is estimated using the static four-step travel demand model (trip generation, trip distribution, modal split, and traffic assignment). A set of five metaheuristic models were developed and implemented for this specific Transit-NDP, namely, Simulated Annealing (SA)-VISUM, Simulated Annealing-Random Forest Regression Model (SA-RF), Tabu Search (TS)-Random Forest (TS-RF), SA-RF-TS-VISUM, SA-RF-VISUM. These models were evaluated using two test networks …


Adhesively Bonded Multi-Material Single Lap Joints Under Static Tensile Loading, Yesim Kokner Jan 2022

Adhesively Bonded Multi-Material Single Lap Joints Under Static Tensile Loading, Yesim Kokner

Dissertations and Theses

Adhesive joints are widely used in a variety of industrial applications utilizing the improved mechanical properties they provide over traditional mechanical joining methods. [1] The lap joint is a usual test specimen with a view to assessing the strength and properties of joints.

This study deals with the stiffness, strength and fracture behavior of multi-material single-lap joints. It describes the mechanical behavior of a multi-material single lap joints subjected to static tensile loading in the longitudinal direction. First, steel-to-steel and aluminum-to-aluminum joints are tested to establish baseline data. Subsequently, multi-material joints consisting of aluminum-to-steel, aluminum-to-composite, and steel-to-composite joints were tested …


Investigations On Vortex-Induced Vibration (Viv) Phenomena Of Single-And-Double-Cylinder Flexible Beam Arrangements Of Energy Harvesters, Xiaohai Jiang Jan 2022

Investigations On Vortex-Induced Vibration (Viv) Phenomena Of Single-And-Double-Cylinder Flexible Beam Arrangements Of Energy Harvesters, Xiaohai Jiang

Dissertations and Theses

Due to the battery lifespan limitation and the need for periodical replacement, energy-harvesting is an actual alternative as a power source for low power devices in some special areas. And among them, the piezoelectric energy-harvesting, which converts mechanical (vibration) into electric energy, is the fastest development one in recent years.

In our current work, a piezoelectric harvester with a finite length cylinder fixed to one end of a flexible thin beam, is the research object in an incoming flow in the CCNY wind tunnel. We report on the efforts to improve the state-of-the-art harvester, called reconfigurable harvester, which has functions …


The Impact Of Covid-19 On Building Energy Consumption In New York City, Martha A. Olaleye Jan 2022

The Impact Of Covid-19 On Building Energy Consumption In New York City, Martha A. Olaleye

Dissertations and Theses

Since February 2020, the spread of COVID-19 affected the world economy, with the population of people contacting the virus in New York City at that time being at the highest in the United States of America. Thus, the need for remote/online learning was adopted for the safety of faculty, staffs, and students of New York Educational institution like CCNY. In the study, I focused on energy consumption as regards to COVID and POST-COVID periods in New York City (NYC), since most employees are working from home and schools are online which implies that most commercial buildings are vacant. Also due …


Wave Engineering In Time Modulated, Nonlinear, And Anisotropic Metamaterials, Ahmed Mekawy Jan 2022

Wave Engineering In Time Modulated, Nonlinear, And Anisotropic Metamaterials, Ahmed Mekawy

Dissertations and Theses

Leveraging wave matter interactions is central to a myriad of electromagnetic wave-based applications. During the past decades, research on extreme wave manipulation has been revolutionized by artificially engineered materials (metamaterials) and by adding new aspects to the wave-matter interactions that showed intriguing results inaccessible in conventional linear, time invariant (LTI), passive and isotropic media. In this work, I will explore, numerically and experimentally, the possibility of realizing devices that perform beyond or close to their fundamental LTI limitations by adding periodic modulation, nonlinearity, and gain. I will demonstrate these concepts at radio frequencies (RF) and at optical frequencies. Specifically, at …


Analysis Of Eye Movements To Cartoon Faces In Videos, Kaustubh Sapru Jan 2022

Analysis Of Eye Movements To Cartoon Faces In Videos, Kaustubh Sapru

Dissertations and Theses

Saccades are rapid eye movements that move our gaze between successive points of fixation. They are indicative of how we direct our attention and therefore play a role in memory and cognition. For static images, it is established that saccades move faster to faces compared to other objects. We hypothesize that the same is true for videos. To test this hypothesis, saccades to faces in motion pictures have been analyzed. The analysis here entails the recording of saccades to two videos followed by a statistical study of saccades going towards faces or going away from faces. What makes this study …


Ai-Driven Automated Medical Imaging Analysis, Jingya Liu Jan 2022

Ai-Driven Automated Medical Imaging Analysis, Jingya Liu

Dissertations and Theses

Medical imaging has been applied widely in many clinical diagnoses to detect and differentiate abnormalities by revealing the internal structure of the human body at normal anatomical and physiological levels. Manual analyzing medical images demands attention and is time-consuming, requiring well-trained expertise. The speed, fatigue, and experience may limit the diagnostic performance, leading to delays and even false diagnoses that significantly impact patient treatment. Therefore, accurate systematic systems based on medical image analysis are crucial for timely clinical diagnosis.

This dissertation focuses on advancing automatic computer-aided diagnosis systems to detect cancer, assisting radiologists with early intervention to improve survival rates. …


Evaluation Of Snow And Streamflow In The National Water Model With Analysis Using Machine Learning, Engela Sthapit Jan 2022

Evaluation Of Snow And Streamflow In The National Water Model With Analysis Using Machine Learning, Engela Sthapit

Dissertations and Theses

Snow has great influence on land-atmosphere interactions and snowmelt from the mountains is a vital water source for downstream communities dependent on snow fed lakes, rivers and streams. This study explored the snow and streamflow prediction capabilities of process-based numerical prediction and data-driven machine learning models.

The overall goal of this study was to understand the deficiencies in the NOAA’s National Water Model (NWM) to represent snow, subsequently streamflow, and recognize the areas where it could be improved for future model developments. The goal was also to evaluate if the recent advancements in machine learning techniques is useful for predicting …


Shear Thickening In Dense Bidisperse Suspensions By Dynamic Simulation, Nelya Malbranche Jan 2022

Shear Thickening In Dense Bidisperse Suspensions By Dynamic Simulation, Nelya Malbranche

Dissertations and Theses

Shear thickening, which corresponds to an increase of viscosity with shear rate, is ubiquitously observed in many concentrated suspensions and, as such, has implications for many industrial materials and geological phenomena. Controlling shear thickening is of significant importance, and many studies have been devoted to it. Recent works link shear thickening to the shear-induced transition from a lubricated particle interaction at low shear stress to a predominantly frictional interaction at high stress. In this dissertation, we investigate bidispersity and focus on mechanisms contributing to the viscosity evolution in rate-dependent suspensions, something that has not been addressed before. We perform detailed …


Design And Control Of Quasi-Direct Drive Actuation For Lightweight And Versatile Wearable Robots, Shuangyue Yu Jan 2022

Design And Control Of Quasi-Direct Drive Actuation For Lightweight And Versatile Wearable Robots, Shuangyue Yu

Dissertations and Theses

Wearable robots have shown great potential for augmenting the physical capabilities of humans in lab settings. However, wearable robots for augmenting the physical capabilities of humans under community-based conditions are the new frontier of robotics. Furthermore, the design and control are still considered to be grand challenges for providing physical augmentation for humans. In terms of design, the state-of-the-art exoskeletons are typically rigid, bulky, and limited to lab settings. In terms of control, most of the rhythmic controllers are not versatile and are focused only on steady-state walking assistance.

The motivation behind my research is to improve both the design …


Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi Jan 2022

Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi

Dissertations and Theses

There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The …


Investigation Of Reactions Occurring In Municipal Solid Waste Residues, Tasnuva T. Moutushi Jan 2022

Investigation Of Reactions Occurring In Municipal Solid Waste Residues, Tasnuva T. Moutushi

Dissertations and Theses

Each year more than 290 million tons of municipal solid waste (MSW) is generated in the U.S. Understanding the reactions occurring in waste during disposal, transport, and storage is important to move towards an integrated waste management strategy. Recently some landfills in the U.S. have been reported to exceed the regulatory temperature range, causing numerous regulatory challenges. The reason for this phenomenon is still unidentified. In addition, the co-disposal of the MSW ash in landfills lead to various reactions which can impact the landfill environment. Understanding the reactions occurring in the MSW and in ash is essential to minimize and …


Investigation Of Recyclable And Renewable Crude Oil From Biomass And Plastics, Golam Chowdhury Jan 2022

Investigation Of Recyclable And Renewable Crude Oil From Biomass And Plastics, Golam Chowdhury

Dissertations and Theses

In the present world, the nonrenewable source of petroleum crude oil is suspected to cause irreversible climate impacts. So, refinery companies are looking for renewable and recyclable crude oil (RCOs). Biomass and Plastics are a great sources of RCOs. The goal of this work is to design, build and operate a pyrolysis reactor which is capable of converting different solid feedstock derived from waste to pyrolysis oil. The oils are characterized by GC-MS and sent to BASF Corporation in Iselin, NJ for catalytic upgrading potential. In this study, the feedstock ranged from virgin plastic resins (LDPE, HDPE, PS, PP), recycled …


The Study Of 3d Micro-Fluid Printing In Aqueous Two-Phase System, Mian Huang Jan 2022

The Study Of 3d Micro-Fluid Printing In Aqueous Two-Phase System, Mian Huang

Dissertations and Theses

Aqueous two-phase system (ATPS) is a technology that allows phase separation in an aqueous environment. This technology can be used for the separation, extraction and purification of a variety of biomolecules and thus gained great attention in industry and academia. This thesis is a combination of ATPS, 3D printing, and microfluidics technologies and realizes the printing of biocompatible aqueous structures in another aqueous matrix. The objectives of this thesis include 1) customizing a regular thermal extrusion 3D printer for printing 3D aqueous structures, 2) printing 3D aqueous structure in an aqueous matrix, and 3) studying the stability of the printed …


Ternary Flow Simulation Based On The Conservative Phase Field Lattice Boltzmann Method, Chunheng Zhao Jan 2022

Ternary Flow Simulation Based On The Conservative Phase Field Lattice Boltzmann Method, Chunheng Zhao

Dissertations and Theses

In this thesis, we numerically investigated multi-phase fluid dynamics (2 and 3-phase flow) by solving the Navier-Stokes equations coupled with the conservative phase field (CPF) equations using the Lattice Boltzmann method (LBM). To effectively simulate the large-scale multi-phase physics, we developed an open-source software, IMEXLBM, which can be easily parallelized on both CPUs and GPUs without significant modifications to the code. We first validated various parts of this software and then used this method to study the interaction of rising bubbles with a static oil droplet as well as the engulfment of the water droplet on solids coated with a …


Novel Mechanisms Of Dc And Kilohertz Electrical Stimulation, Zeinab Esmaeilpour Jan 2022

Novel Mechanisms Of Dc And Kilohertz Electrical Stimulation, Zeinab Esmaeilpour

Dissertations and Theses

Transcranial electrical stimulation is a promising technique where a weak electrical current is applied to the scalp with the goal of modulating brain activity. Understanding the cellular mechanism of direct current (DC) and kilohertz (kHz) electrical stimulation is of broad interest in neuromodulation. More specifically, there is a large mismatch between enthusiasm for clinical applications of the method and understanding of DC and kHz novel mechanisms of action. This dissertation is centered around two main fundamental aims: 1) systematic study of the acute and long-term effects of kilohertz electrical stimulation and amplitude-modulated waveform with kHz carrier frequency using a well-established …


Impact Of Percutaneous Transluminal Intervention On Vascular Hypoxia And The Role Of Micro-Calcifications On Atherosclerotic Plaque Rupture, Andrea Corti Jan 2022

Impact Of Percutaneous Transluminal Intervention On Vascular Hypoxia And The Role Of Micro-Calcifications On Atherosclerotic Plaque Rupture, Andrea Corti

Dissertations and Theses

Atherosclerotic disease is initiated by cholesterol build-up beneath the endothelium, which evolves into a fibroatheroma, a lipid-rich plaque covered by a fibrous cap. Many of these plaques are considered as vulnerable, as they grow to occlude the luminal section of the artery (chronically stenotic) or become mechanically unstable with a higher chance of rupturing (rupture-prone). On one hand, chronically stenotic vulnerable plaques are symptomatic lesions that are often treated with Percutaneous Transluminal Intervention (PTI). Unfortunately, approximately 10% of PTI procedures are followed by severe Neointima Hyperplasia (NH), which causes a new occlusion and failure of the implant. A significant precursor …


Neural Processing Of Semantic Content In Movies, Maximilian Nentwich Jan 2022

Neural Processing Of Semantic Content In Movies, Maximilian Nentwich

Dissertations and Theses

Naturalistic stimuli, such as movies, contain interacting, multimodal and semantic features and allow for free exploration through eye movements. The full extent of neural responses to features such as motion, film cuts and eye movement behavior has not been established. The main hypothesis of this thesis is that complex multimodal and semantic stimuli in naturalistic movies engage a widespread ensemble of locations across the entire brain. To address this question I analyzed simultaneous intracranial and eyetracking data from over 6,000 electrodes across 23 patients with intractable epilepsy. Responses to fast eye movements – saccades – and film cuts are widespread …


Understanding And Controlling Failure Mechanisms Of The Zinc Anode For Rechargeable Alkaline Batteries, Michael J. D'Ambrose Jan 2022

Understanding And Controlling Failure Mechanisms Of The Zinc Anode For Rechargeable Alkaline Batteries, Michael J. D'Ambrose

Dissertations and Theses

In the coming years, the transformation of the electric grid will be in part enabled by safe, low-cost, and reliable large-scale rechargeable battery energy storage systems. Zinc (Zn) alkaline electrodes hold great importance and promise in the battery technology community as they satisfy the safety and cost requirements, yet their behavior in real world application is still poorly understood.

Two experimental studies were carried out, the first of which investigates failure mechanisms and material evolution during cycling of 27 zinc-manganese dioxide (Zn-MnO2) cells in 37 wt% potassium hydroxide (KOH) electrolyte wherein the percent utilization of the theoretical capacity …


On A New Framework For Detecting, Classifying, And Forecasting Floods For Large-Scale Flood Risk Analysis, Equisha Glenn Jan 2022

On A New Framework For Detecting, Classifying, And Forecasting Floods For Large-Scale Flood Risk Analysis, Equisha Glenn

Dissertations and Theses

Increasing trends in flooding events are projected to continue as climate changes have increased the chance of extreme weather events. Given the significant, damaging impacts of extreme floods, the ability to effectively model floods is crucial for risk management and mitigation of the impacts of these extreme flooding events. This dissertation presents a new framework for detecting and predicting large-scale flood risk in the United States using climate information. This methodology categorizes regional, simultaneous floods into an index that is used to forecast the risk of extreme flooding a season ahead. The index proposed herein, named the Spatial Flood Index …


Understanding The Relationship Between Urban Areas And The Boundary Layer Using Remote Sensing Methods, Gabriel A. Rios Jan 2022

Understanding The Relationship Between Urban Areas And The Boundary Layer Using Remote Sensing Methods, Gabriel A. Rios

Dissertations and Theses

The atmospheric boundary layer is crucial to the exchange in energy between the Earth's surface and the atmosphere. Within this layer, the majority of human activities are carried out, which makes understanding the boundary layer especially important for many of our interests. A key component of this energy exchange is found at the surface, was surface properties are the interface through which momentum, heat, moisture, and other fluxes are transferred between media. Not only does the surface act as an interface, but as an actor that influences the exchange efficiency and rates. This concept is the crux of atmospheric boundary …


Exosome- And Microrna-Based Therapeutic Approach For Tendinopathy, Angela Wang Ilaltdinov Jan 2022

Exosome- And Microrna-Based Therapeutic Approach For Tendinopathy, Angela Wang Ilaltdinov

Dissertations and Theses

Tendinopathy, characterized by degeneration and chronic inflammation, is a significant clinical burden. Current treatments focus on symptom management but do not sufficiently address its underlying pathology; however, stem cell-based approaches aimed at repairing diseased tissues may overcome this limitation. Therapeutic effects of stem cells may be due in part to paracrine actions, including some mediated by exosomes – extracellular vesicles secreted by cells that play a role in cell communication. MicroRNA (miRNA), small non-coding RNA carried by exosomes, are likely responsible for many exosome effects. Exosomes and miRNA therapies show promise in treating diseases such as cancer and arthritis, but …


Crop Water Deficits And Their Season-Ahead Climate Determinants Across The United States, Siena W. Dante Jan 2022

Crop Water Deficits And Their Season-Ahead Climate Determinants Across The United States, Siena W. Dante

Dissertations and Theses

The agricultural sector in the United States provides an essential food and revenue source and it faces severe challenges due to increasing climate variability, which reduces reliable access to water needed for the crops. Unreliable access to water and the potential for drought result in major economic losses to the sector as well as potentially significant environmental damage. It is thus necessary to mitigate the effects of drought as well as to develop agricultural practices that include preparedness strategies for droughts. To develop these strategies, comprehensive information about droughts must be available early enough to consider before the growing season. …