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Nonlinear Finite Element Model For Functionally Graded Porous Circular/Annular Micro-Plates Under Thermal And Mechanical Load, Enrique Nava Munoz Dec 2023

Nonlinear Finite Element Model For Functionally Graded Porous Circular/Annular Micro-Plates Under Thermal And Mechanical Load, Enrique Nava Munoz

Masters Theses

A nonlinear finite element model for micro circular/annular plates under thermal and mechanical loading is developed using a third order shear deformation theory. In the kinematic assumptions, the change of plate thickness is allowed and no transverse shear strains are considered on the top and bottom surfaces. A power-law distribution is utilized to account for variations of two constituents through the thickness of the plate. Three different types of porosity distributions are considered. The strain gradient effect in micro scale structures is considered using the modified couple stress theory. The dynamic version of the principle of virtual displacements is used …


Advancing Winter Weather Adas: Tire Track Identification And Road Snow Coverage Estimation Using Deep Learning And Sensor Integration, Parth Kadav Dec 2023

Advancing Winter Weather Adas: Tire Track Identification And Road Snow Coverage Estimation Using Deep Learning And Sensor Integration, Parth Kadav

Masters Theses

No abstract provided.


Investigating Disparities And Safety Equity In Pedestrian Nighttime Crashes In Michigan, Sia Isaria Mwende Jun 2023

Investigating Disparities And Safety Equity In Pedestrian Nighttime Crashes In Michigan, Sia Isaria Mwende

Masters Theses

For the past eleven years (2011 - 2021) in Michigan, 76 percent of all fatal pedestrian crashes occurred at night. Over the same period, about 36 percent of pedestrian nighttime crashes were fatal or incapacitating (KA), while only 25 percent of daytime pedestrian crashes were fatal or incapacitating (KA). Previous studies suggest that, overall, poor neighborhoods and racial minorities are associated with more pedestrian crashes. With more fatal and incapacitating pedestrian crashes occurring at night, it is imperative to examine how these crashes are distributed by economic status and racial makeup. Therefore, this study aims to investigate the racial and …


On Hydrophobic Deep Eutectic Solvents: Thermo-Physical Properties And Applications In Gas Solubility, Shan Khai Liew Apr 2023

On Hydrophobic Deep Eutectic Solvents: Thermo-Physical Properties And Applications In Gas Solubility, Shan Khai Liew

Masters Theses

Carbon dioxide (CO2) has been widely recognized as one of the greenhouse gases (GHGs) in the atmosphere. GHGs cause global warming, which will bring a lot of problems and irreversible changes. To curb CO2 emissions, much effort has been done. There are many technologies available for CO2 capture, such as amine scrubbing, pressure or temperature swing adsorption, membrane separation, and many solvents and absorbents that have been proposed for CO2 capture (e.g., zeolite, silica materials, graphene, activated carbon, etc.) at every stage (pre-combustion, post-combustion, oxy-combustion). However, these materials have their own drawbacks. Hydrophobic deep eutectic solvents (HDES) is a green …


Improving Future Vehicle Fuel Economy And Operational Design Domain Through Novel Data Pipelines, Kyle James Carow Apr 2023

Improving Future Vehicle Fuel Economy And Operational Design Domain Through Novel Data Pipelines, Kyle James Carow

Masters Theses

Modern automobiles have greatly advanced in recent years, with technological developments that enhance performance, safety, and comfort. However, there is still much room for improvement. Today’s vehicles are heavily reliant on the combustion of fossil fuels, proven to be harmful for the environment on both a local and global scale. In addition, the safety benefits of autonomous vehicles and advanced driver assistance systems are not yet fully realized due to the limited operational design domain of these technologies. In this research, these needs are addressed through the development of two novel data pipelines. In the first study, a novel methodology …


Implementation Of The Plan For Every Part (Pfep) Tool And Additional Methodologies For Operational Improvement., Bernardo Luis Borges Pedroso Dec 2022

Implementation Of The Plan For Every Part (Pfep) Tool And Additional Methodologies For Operational Improvement., Bernardo Luis Borges Pedroso

Masters Theses

The work focused on the inventory management of Dimplex Thermal Solutions, which had a profoundly overstocked warehouse and was suffering from significant operating expenses, due to the absence of a grounded ordering policy and the need to rent external storage space, respectively.

The main objective of the thesis was to solve the primarily mentioned problems, by constructing a Plan For Every Part (PFEP) tool, followed by the application of an inventory policy and the proposal of a redesigned warehouse layout, to compute ideal stock values and calculate the footprint requirements for Dimplex’s updated inventory levels, respectively. The execution step concerned …


The Design And Development Of A Miniature Gridded Ecr Ion Thruster, Nicholas Nuzzo Dec 2022

The Design And Development Of A Miniature Gridded Ecr Ion Thruster, Nicholas Nuzzo

Masters Theses

Plasma propulsion, a specific subset of electric propulsion (EP), is a class of space propulsion that produces plasma by excitation of a propellant at or above its ionization energy. This ionized propellant is then accelerated by an externally applied field (magnetic and/or electric) and produces thrust. There is an increasing need for miniaturization in spacecraft technology and the use of plasma EP devices in space propulsion. These systems provide an advantage over traditional chemical propulsion solutions which are less efficient and have more mass. Miniaturization of EP devices allows missions to have more space and mass available for their payloads …


Measurement Of Low-Speed Impinging Jet Structure Using Temperature Sensitive Paint, Arthur Dean Woodworth Dec 2022

Measurement Of Low-Speed Impinging Jet Structure Using Temperature Sensitive Paint, Arthur Dean Woodworth

Masters Theses

Temperature sensitive paint (TSP) is used to analyze surface flow structures driven by a jet impinging on a heated steel sheet. Temperature and Nusselt number images are calculated from CCD images of the TSP surface. TSP calibration is discussed. Skin friction data is obtained from the temperature images.

Data is collected for metal and 3D-printed plastic nozzles of varying shape and size at one or two jet airspeeds depending on the nozzle. For the circular nozzles, data is collected for four Reynolds numbers at impinging angles of 90, 70, and 50 degrees. For the elliptical nozzles and the star-shaped nozzle, …


Development Of A Ppg Sensor Array As A Wearable Device For Monitoring Cardiovascular Metrics, Jose Ignacio Rodriguez-Labra Apr 2022

Development Of A Ppg Sensor Array As A Wearable Device For Monitoring Cardiovascular Metrics, Jose Ignacio Rodriguez-Labra

Masters Theses

Wearable devices with integrated sensors for tracking human vitals are widely used for a variety of applications, including exercise, wellness, and health monitoring. Photoplethysmography (PPG) sensors use pulse oximetry to measure pulse rate, cardiac cycle, oxygen saturation, and blood flow by passing a light beam of variable wavelength through the skin and measuring its reflection. A multi-channel PPG wearable system was developed to include multiple nodes of pulse oximeters, each capable of using different wavelengths of light. The system uses sensor fusion along with a machine learning model to perform feature extraction of relevant cardiovascular metrics across multiple pulse oximeters …


Dynamic Maneuvers For Satellite On-Orbit Servicing Utilizing Novel Continuum Robotics: Development & Experimentation, Nathan Dalton Apr 2022

Dynamic Maneuvers For Satellite On-Orbit Servicing Utilizing Novel Continuum Robotics: Development & Experimentation, Nathan Dalton

Masters Theses

Robotic on-orbit servicing is a developing technology that seeks to increase the longevity and repairability of faulty or aging resident space objects. In this research, the development of a flexible continuum manipulator for a small satellite system that performs low-complexity on-orbit servicing or debris removal is presented. Derivations of manipulator kinematics are described in detail, a non-linear control scheme has been developed, and the accuracy and servicing applications for the prototype are evaluated and discussed. The manipulator has been tested on an air-bearing dynamics simulator, and the results are extensively analyzed. System recommendations and future work suggestions are presented.


Design And Optimization Of An Electron Cyclotron Resonance Thruster, Austen Thomas Apr 2022

Design And Optimization Of An Electron Cyclotron Resonance Thruster, Austen Thomas

Masters Theses

Presented in this work is the process in the design and optimization of a coaxial electron cyclotron resonance thruster. Electron cyclotron resonance thrusters are novel microwave-based thrusters which possess select technological advantages over mature electric propulsion concepts such as being electrodeless and only requiring a single power source. The thruster constructed in this work is a coaxial configuration and is termed the Western electron cyclotron resonance thruster. Thruster dimensions were optimized based on past experimentation completed with ECR thrusters. In an attempt to enhance the microwave plasma coupling of the coaxial thruster design three different antenna configurations were considered: a …


Standardized 1x6u Cubesat Structure Design, Maximilian H. Brummel Nov 2021

Standardized 1x6u Cubesat Structure Design, Maximilian H. Brummel

Masters Theses

A CubeSat is a small satellite composed of one or more 10cm x 10cm x ~10cm cubes. Sometimes referred to as a “U” as in unit, the cubes can be combined in configurations of 2U, 3U, 6U, and more. CubeSats provide many advantages that larger satellites cannot offer. They are relatively inexpensive and can be fabricated much faster. Small-scale projects that require a fast timeline from conception up to completion are perfect for CubeSats. Furthermore, educational programs use CubeSat projects to teach and prepare students for the satellite industry. Popular configurations for CubeSat are 1U, 3U and 6U where the …


Development Of A Highly Sensitive Pressure Sensing System With Custom-Built Software For Continuous Physiological Measurements, Masoud Panahi Aug 2021

Development Of A Highly Sensitive Pressure Sensing System With Custom-Built Software For Continuous Physiological Measurements, Masoud Panahi

Masters Theses

In this work, a pressure sensing system was designed and fabricated by developing a highly sensitive cone-structured pressure sensor with a custom-built software for physiological monitoring applications. A novel highly sensitive cone structured porous polydimethylsiloxane (PDMS) based pressure sensor capable of detecting very low-pressure ranges was developed for respiration monitoring. The pressure sensor was fabricated using a master mold, a hybrid-structured dielectric layer, and fabric-based electrodes. The master mold with inverted cone structures was created using a rapid and precise three-dimensional (3D) printing technique. The dielectric layer, with pores and cone structures, was prepared by annealing a mixture of PDMS, …


Towards Real-Time Energy Efficiency Analysis Of A Hydraulic System, Montasir Mamun Mithu Aug 2021

Towards Real-Time Energy Efficiency Analysis Of A Hydraulic System, Montasir Mamun Mithu

Masters Theses

The study aims at developing a real-time data analysis system for the energy efficiency study of hydraulic systems. It also aims at implementing automation for hydraulic systems so that energy efficiency can be improved using the real-time approach. This research uses a system-level experimental methodology. A linear push system hydraulic prototype is developed for the study. The prototype contains hydraulic actuator, shock absorber, electronic flow control valve, and electronic sensor. This prototype is used to experiment with different operating conditions to characterize hydraulic system behavior. A real-time data analysis system is developed using LabVIEW and an Open Platform Communication (OPC) …


Simulation Of Transient Conditions In Vehicle-To-Grid Systems Fed From Plug-In Electric Vehicles, Olapade Oludolapo Olagbemi May 2021

Simulation Of Transient Conditions In Vehicle-To-Grid Systems Fed From Plug-In Electric Vehicles, Olapade Oludolapo Olagbemi

Masters Theses

The increasing adoption of plug-in electric vehicles for commercial and consumer needs, coupled with government targets and incentives for use of renewable energy sources and reduction of greenhouse gases [1, pp. 44-45], has led to their consideration as power sources. Such vehicle-to-grid (V2G) systems seek to take advantage of the aggregate energy available within fleets of electric vehicles connected to power grids through bi-directional charging stations, by using them as distributed power sources for load leveling and peak shaving on the power grids [2]. Unfortunately, V2G systems can introduce power quality issues, such as harmonics, with associated transients that pose …


Synthesis And Characterization Of Non-Pgm Catalysts For Fuel Cell Applications, Sudharsan Sridhar Dec 2020

Synthesis And Characterization Of Non-Pgm Catalysts For Fuel Cell Applications, Sudharsan Sridhar

Masters Theses

Fuel Cells convert the chemical energy of a fuel and an oxidizing agent into electricity through a pair of redox reactions. Proton Exchange Membrane (PEM) fuel cells convert (efficiency-60%) hydrogen and air to power the electric motors with zero emissions, facilitating the development of environmentally friendly and sustainable automobile technologies. One of the major obstacles for larger commercial viability of Fuel Cells for automobile applications is their cost-effectiveness. Currently, fuel cells use platinum as a catalyst material, which is prohibitively expensive for commercial automobile applications. The development of non-Platinum Group Metal (non-PGM) catalyst materials with similar electrochemical performance to that …


Cellular Attachment On Poly(Lactic Acid) For Use In Tissue Engineering, Stephen R. Hunter Dec 2020

Cellular Attachment On Poly(Lactic Acid) For Use In Tissue Engineering, Stephen R. Hunter

Masters Theses

Tissue engineering is a promising new method for organ regeneration. This method can be used to repair damaged tissue, or possibly replace a fully functional organ. In summary, a biopsy is taken from a donor, isolated, then grown onto a framework resembling an organ. Once grown; it is then transplanted into the patient. Over time, the body will degrade the scaffold, leaving the organ or tissue in its place. As this scaffold is present in the body for an extended time; factors like biocompatibility, toxicity, immunogenicity, and structural stability must be researched.

Several polymers have already been researched for use …


Atherosclerosis: Pathology, Role Of Sd-Ldl, Particle Size Characterization Of Sd-Ldl With Multiangle Light Scattering, Akshay Sudhakar Ukey Dec 2020

Atherosclerosis: Pathology, Role Of Sd-Ldl, Particle Size Characterization Of Sd-Ldl With Multiangle Light Scattering, Akshay Sudhakar Ukey

Masters Theses

Atherosclerosis is an inflammatory disease due to the accumulation of lipids in the inner wall of arteries. As per the report of Center of Diseases Control and Prevention (CDC), 1 in every 4 deaths is due to heart diseases each year. Atherosclerosis occurs when artery walls harden by the buildup of cholesterol, forming multiple atherosclerotic plaques within the aorta (4). Out of the modern medicines available to control cholesterol, statin is amongst the foremost widely used because it is both safe and effective in lowering high risk patients (9). However, usage of high statins dosage typically leads to some mild …


Development Of A Single Emitter Ionic Liquid Ion Source Research Platform, Thomas V. Kerber Dec 2020

Development Of A Single Emitter Ionic Liquid Ion Source Research Platform, Thomas V. Kerber

Masters Theses

A single emitter ionic liquid ion source using porous borosilicate glass was developed. Two emitters with different radii of curvatures were tested using 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI-BF4). I-V curves of the currents on the extractor electrode and a collector plate were obtained for potential differences between the emitter and the extractor ranging from 0 V to 3500 V. For the first emitter chip, extraction began near 2400 V. The highest emission current measured on the first chip was 80 µA at 3500 V with an interception current on the extractor of 4.86 µA. An new collector plate was used …


A Framework To Support Automatic Certification For Self-Adaptive Systems, Ioannis Nearchou Aug 2020

A Framework To Support Automatic Certification For Self-Adaptive Systems, Ioannis Nearchou

Masters Theses

Presently, cyber-physical systems are increasingly being integrated into societies, from the economic sector to the nuclear energy sector. Cyber-physical systems are systems that combine physical, digital, human, and other components, which operate through physical means and software. When system errors occur, the consequences of malfunction could negatively impact human life. Academic studies have relied on the MAPE-K feedback loop model to develop various system components to satisfy the self-adaptive features, such that violation of the safety requirements can be minimized. Assurance of system requirement satisfaction is argued through an industrial standard form, called an assurance case, which is usually applied …


Flexible Capacitive Pressure Sensors And Triboelectric Energy Harvesters Using Laser-Assisted Patterning Process For Flexible Hybrid Electronic Applications, Valliammai Palaniappan Jul 2020

Flexible Capacitive Pressure Sensors And Triboelectric Energy Harvesters Using Laser-Assisted Patterning Process For Flexible Hybrid Electronic Applications, Valliammai Palaniappan

Masters Theses

This work focuses on the design, fabrication and characterization of novel flexible capacitive pressure sensors and triboelectric energy harvesters using laser-assisted patterning process for flexible hybrid electronic applications. Initially, the capacitive pressure sensor was developed by fabricating a set of polydimethylsiloxanes (PDMS) dielectric films with pyramid shaped micro-structures using a laser-assisted patterning process. The pressure sensor consists of two electrodes (top and bottom) that were fabricated by depositing silver (Ag) on flexible polyethylene terephthalate (PET) using additive screen-printing process. Finally, the pressure sensor was assembled by attaching the top and bottom Ag electrodes to the smooth side of pyramid shaped …


Prediction Of Isotropic Strain Hardening Material Properties Using Gradient Boosted Regression Tree Method And Hyperparameter Optimization, Darren R. Promer Jul 2020

Prediction Of Isotropic Strain Hardening Material Properties Using Gradient Boosted Regression Tree Method And Hyperparameter Optimization, Darren R. Promer

Masters Theses

In this study a new technique is proposed for the determination of elastic-plastic stress-strain relations for isotropic materials using the force-displacement output from an instrumented indentation test, finite element simulation, and machine learning methods. This non-destructive testing methodology has promising potential for industry implementation. Applications to benefit from this method include the characterization of localized material properties on surface engineered components, and the post-manufacturing assessment of material properties for items such as additively manufactured metallic components and load-bearing welded joints.

Currently, the capability of the instrumented indentation test for determining material properties is limited to the elastic modulus and surface …


A Multiscale Thermomechanical Metal Additive Manufacturing Simulation And The Impact Of Geometry On Residual Stress And Distortion, Luis Fernando Silva Velasco Jul 2020

A Multiscale Thermomechanical Metal Additive Manufacturing Simulation And The Impact Of Geometry On Residual Stress And Distortion, Luis Fernando Silva Velasco

Masters Theses

Metal additive manufacturing is an enabling technology for the rapid prototyping and manufacturing of geometrically complex parts that would otherwise be difficult or impossible to manufacture. However, the manufacturing process can produce undesired residual stresses and distortions. The first part of the work describes the implementation of a multiscale, thermo-mechanical simulation modeling the metal powder bed fusion additive manufacturing process. NASA’s Micromechanics Analysis Code was is to incorporate the microscale effects of an evolving material porosity on the predicted macroscale residual fields. The simulation shows that modeling an evolving material porosity, as the material transitions from a metal powder to …


Optimized System For On-Route Charging Of Battery Electric Buses And High-Fidelity Modelling And Simulation Of In-Motion Wireless Power Transfer, Yogesh Bappasaheb Jagdale Jun 2020

Optimized System For On-Route Charging Of Battery Electric Buses And High-Fidelity Modelling And Simulation Of In-Motion Wireless Power Transfer, Yogesh Bappasaheb Jagdale

Masters Theses

Electrifying cars, buses and trucks is an attractive means to reduce energy use and emissions, because it involves minimal restructuring of the transportation network. Transit buses drive fixed routes, minimizing driver range anxiety by properly sizing energy storage system but the major challenge to fully electrifying transit buses, is the amount of energy they consume in a day of driving. To enable a full day of operation, batteries need to be large, which is expensive and heavy. This work utilizes real-world transit bus data fed to a battery electric drive-train model to co-optimize charger locations, charger power levels, and vehicle …


Numerical Performance Evaluation Of The Wooden Frame Structures With Adhesive Applied Connection Under Wind And Seismic Loading, Sharthak Bhandary Jun 2020

Numerical Performance Evaluation Of The Wooden Frame Structures With Adhesive Applied Connection Under Wind And Seismic Loading, Sharthak Bhandary

Masters Theses

The objective of the research is divided into two folds. The first objective is to study the state-of-the-art modeling method for the wooden frame construction, while the second objective is to evaluate the performance of a wooden frame structure with construction adhesives under hazardous loading conditions using the selected numerical modeling method. The numerical modeling tools were classified under academic and commercial categories based on the purpose of their development. Both academic and commercial tools were further classified based on model types of the structural systems (i.e., shear walls and three-dimensional (3D) buildings) and the applied loads (i.e., wind loading …


Development Of A Finite Element Model Of The Stamping Process To Predict The Natural Frequencies Of Dimpled Beams, Varad Vasudeo Pendse Apr 2020

Development Of A Finite Element Model Of The Stamping Process To Predict The Natural Frequencies Of Dimpled Beams, Varad Vasudeo Pendse

Masters Theses

Creating dimples on beams has been proven to be an effective way of altering their vibrational behavior. The objective of this research is to simulate the process of stamping using the finite element (FE) method to create a model of a dimpled beam. This dimple has non-uniform thickness, so it shows close agreement with its real-life counterpart.

ANSYS® Parametric Design Language (APDL) is used to build a three-dimensional (3-D) finite element model and simulate the process of stamping used to create the dimple. The structural simulation is validated by calculating the thickness and width of the deformed geometry of the …


Cellulose Based Separator For High-Performance Lithium-Ion Batteries, Akshit Vaidya Apr 2020

Cellulose Based Separator For High-Performance Lithium-Ion Batteries, Akshit Vaidya

Masters Theses

During the past two decades, lithium-ion batteries (LIBs) have gained great success in the field of portable devices, and currently, are penetrating to the market of vehicles. Compared to the fast development of LIBs, little efforts have been dedicated to the separator, which is one of the most important components of LIBs. Primarily, the lithium-ion battery separator has two functions, one is to prevent direct contact between the positive and negative electrodes, and the other is to provide a path for effective ionic transportation. Currently, the separator market of LIBs is dominated by polyolefin materials such as polypropylene, polyethylene, and …


Vehicle Velocity Prediction Using Artificial Neural Networks And Effect Of Real-World Signals On Prediction Window, Tushar Dnyaneshwar Gaikwad Apr 2020

Vehicle Velocity Prediction Using Artificial Neural Networks And Effect Of Real-World Signals On Prediction Window, Tushar Dnyaneshwar Gaikwad

Masters Theses

Prediction of vehicle velocity is essential since it can realize improvements in the fuel economy/energy efficiency, drivability, and safety. Many publications address velocity prediction problems, yet there is a need for the understanding effect of different signals for the prediction. There are numerous new sensor and signal technologies like vehicle-to-vehicle and vehicle-to-infrastructure communication that can be used to obtain comprehensive datasets. Several references considered deterministic and stochastic approaches that use the datasets as input to determine future operation predictions. These approaches include different traffic models and artificial neural networks such as Markov chain, nonlinear autoregressive model, Gaussian function, and recurrent …


Oxidized Phospholipid Regulation Of Chronic Inflammation In Endothelial Cells, Cameron Scott Brutsche Apr 2020

Oxidized Phospholipid Regulation Of Chronic Inflammation In Endothelial Cells, Cameron Scott Brutsche

Masters Theses

Atherosclerosis, the primary cause of Coronary Heart Disease (CHD), has become one of the top causes of death in the world. As low-density lipoprotein (LDL) particles become trapped and oxidized inside arterial walls, the primary oxidation products of 1-palmitoyl-2-arachidonyl-sn-glycerol-3-phosphatidylcholine (PAPC) induce the binding of monocytes which can potentially lead to fatty plaque build ups. A fragment of one of these oxidation products, OxPAPC, has previously been studied and can act as standard for testing new phospholipids and how they affect protein expression levels. The central hypothesis of this study was that three newly studied classes of oxidized fatty …


Comparison Of Optimal Energy Management Strategies Using Dynamic Programming, Model Predictive Control, And Constant Velocity Prediction, Amol Arvind Patil Apr 2020

Comparison Of Optimal Energy Management Strategies Using Dynamic Programming, Model Predictive Control, And Constant Velocity Prediction, Amol Arvind Patil

Masters Theses

Due to the recent advancements in autonomous vehicle technology, future vehicle velocity predictions are becoming more robust which allows fuel economy (FE) improvements in hybrid electric vehicles through optimal energy management strategies (EMS). A real-world highway drive cycle (DC) and a controls-oriented 2017 Toyota Prius Prime model are used to study potential FE improvements. We proposed three important metrics for comparison: (1) perfect full drive cycle prediction using dynamic programming, (2) 10-second prediction horizon model predictive control (MPC), and (3) 10-second constant velocity prediction. These different velocity predictions are put into an optimal EMS derivation algorithm to derive optimal engine …