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Articles 2761 - 2790 of 11122

Full-Text Articles in Engineering

Shape Parameter & Nodal Distribution Insensitive Radial Basis Functions For Nonlinear Optimal Control Problems, Ahmed Elsadek Ahmed Elshafee Seleit Jan 2022

Shape Parameter & Nodal Distribution Insensitive Radial Basis Functions For Nonlinear Optimal Control Problems, Ahmed Elsadek Ahmed Elshafee Seleit

Electronic Theses and Dissertations, 2020-2023

Computational optimal control relies mainly on pseudospectral methods. The use of Chebyshev and Legendre polynomials is ubiquitous in the literature. This family of methods has good accuracy characteristics but constraints the nodal distribution to a certain grid that is denser at the boundaries. In this work, a set of novel Coupled Radial Basis Functions (CRBFs) is introduced as an approximation means for the nonlinear optimal control problem. CRBFs are real-valued Radial Basis Functions (RBFs) augmented with a conical spline. They do not require a specific nodal distribution. A plethora of research articles were published on the optimization of the shape …

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Ground To Air Testing Of A Fused Optical-Radar Aircraft Detection And Tracking System, Chester V. Dolph, Thomas Lombaerts, Evan Kawamura, Corey Ippolito, Vahram Stepanyan, Khan M. Iftekharuddin, George Szatkowski, Robert G. Mcswain, Chris Morris, Mahyar R. Malekpour Jan 2022

Ground To Air Testing Of A Fused Optical-Radar Aircraft Detection And Tracking System, Chester V. Dolph, Thomas Lombaerts, Evan Kawamura, Corey Ippolito, Vahram Stepanyan, Khan M. Iftekharuddin, George Szatkowski, Robert G. Mcswain, Chris Morris, Mahyar R. Malekpour

Electrical & Computer Engineering Faculty Publications

Onboard detection and tracking capability are integral to the sensing component in collision avoidance systems needed to safely operate autonomous urban air taxis and small Unmanned Aircraft Systems. Ground-based validation of detection and tracking systems is an important milestone towards the end goal of real-time collision avoidance using onboard sensors and algorithms. In this work, we evaluate three Extended Kalman Filter (EKF) based fusion trackers with radar and vision detection inputs, and compare them with baseline trackers for each sensor type. Performance is assessed using field collected data of ground to air test flights with the sensors co-located on a …

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Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen Jan 2022

Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Unmanned Aerial Vehicles (UAVs), also known as drones, are often considered the solution to complex robotics problems. The significant freedom to explore an environment is a major reason why UAVs are a popular choice for automated solutions. UAVs, however, have a very limited flight time due to the low capacity and weight ratio of current batteries. One way to extend the vehicles' flight time is to use a tether to provide power from external batteries, generators on the ground, or another vehicle. Attaching a tether to a vehicle may constrain its navigation but it may also create some opportunities for …

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Aerodynamic Analysis Of Damage State Missiles Using Overset Meshing Techniques For Application To Computational Fluid Dynamics Simulation, Jonathan A. D'Alessio Jan 2022

Aerodynamic Analysis Of Damage State Missiles Using Overset Meshing Techniques For Application To Computational Fluid Dynamics Simulation, Jonathan A. D'Alessio

Graduate Theses, Dissertations, and Problem Reports (ETD)

Significant research over the years has aimed to redefine the flight capabilities of aircraft after sustaining structural damage to critical components. Flight survivability and controllability are key areas of concern when designing fault-tolerant flight control systems to handle a wide range of potential scenarios. However, there is a lack of research on the impact of physically damaged missile systems. Missile counter-defense and intercept capabilities have become more advanced as the United States has focused heavily on these areas over the years. Damaged missiles due to a kinetic intercept capability present an opportunity for analysis of the post-damage implications on flight …

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Probabilistic Space Weather Modeling And Forecasting For The Challenge Of Orbital Drag In Space Traffic Management, Richard J. Licata Iii Jan 2022

Probabilistic Space Weather Modeling And Forecasting For The Challenge Of Orbital Drag In Space Traffic Management, Richard J. Licata Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the modern space age, private companies are crowding the already-congested low Earth orbit (LEO) regime with small satellite mega constellations. With over 25,000 objects larger than 10 cm already in LEO, this rapid expansion is forcing us towards the enterprise on Space Traffic Management (STM). STM is an operational effort that focuses on conjunction assessment and collision avoidance between objects. While the equations of motion for objects in orbit are well-known, there are many uncertain parameters that result in the uncertainty of an object's future position. The force that the atmosphere exerts on satellite - known as drag - …

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Impact Of Covid-19 On Aviation-Wildlife Strikes Across Europe, Isabel C. Metz, Marta Giordano, Dionysios Ntampakis, Marianna Moira, Anneke Hamann, Rosanne Blijleven, Jürgen J. Ebert, Alessandro Montemaggiori Jan 2022

Impact Of Covid-19 On Aviation-Wildlife Strikes Across Europe, Isabel C. Metz, Marta Giordano, Dionysios Ntampakis, Marianna Moira, Anneke Hamann, Rosanne Blijleven, Jürgen J. Ebert, Alessandro Montemaggiori

Human–Wildlife Interactions

Collisions between aircraft and wildlife (i.e., wildlife strikes) pose a serious threat toward the safety of aircraft, its crew, and passengers. The effects of COVID-19 related travel restrictions on wildlife strikes are unknown. With this study, we aim to address this information gap by assessing the changes of wildlife hazard management performance across European airports during the lockdown period (e.g., period of reduced operations and borders closure in spring 2020). We also sought to raise awareness of the importance of wildlife strike prevention in times of reduced operations. The objective of our study was to compare wildlife strike data before …

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Numerical Investigation On The Effect Of Spectral Radiative Heat Transfer Within An Ablative Material, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin Dec 2021

Numerical Investigation On The Effect Of Spectral Radiative Heat Transfer Within An Ablative Material, Raghava S. C. Davuluri, Rui Fu, Kaveh A. Tagavi, Alexandre Martin

Mechanical Engineering Faculty Publications

The spectral radiative heat flux could impact the material response. In order to evaluate it, a coupling scheme between KATS - MR and P1 approximation model of radiation transfer equation (RTE) is constructed and used. A Band model is developed that divides the spectral domain into small bands of unequal widths. Two verification studies are conducted: one by comparing the simulation computed by the Band model with pure conduction results and the other by comparing with similar models of RTE. The comparative results from the verification studies indicate that the Band model is computationally efficient and can be used to …

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Analysis Of Multiple Degree-Of-Freedom Oscillatory Aquatic Propulsion, Seth Alan Brooks Dec 2021

Analysis Of Multiple Degree-Of-Freedom Oscillatory Aquatic Propulsion, Seth Alan Brooks

Dissertations - ALL

Propulsive performance and flow field data were experimentally measured for a two degree-of-freedom fish platform. The fish platform was designed and constructed based on the yellowfin tuna (\textit{Thunnus albacares}) that is known to be both fast and efficient. This work extends the current understanding of oscillatory aquatic propulsion to a three-dimensional fish platform with full volume flow field data and propulsive performance. A parametric sweep of trailing-edge amplitude of the caudal fin ($A$), heave-to-pitch ratio ($h^*$), and phase offset between the two degrees-of-freedom ($\phi$) was used to explore a parameter space that encompasses and extends beyond the known biological domain. …

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Direct Foam Writing In Microgravity, Guy Jacob Cordonier, Cicely Sharafati, Spencer Mays, Lukas Thackery, Ellena Gemmen, Samuel Cyphert, Megan Brown, John Quinn Napolillo, Savannah Toney, Hunter Moore, John M. Kuhlman `, Konstantinos A. Sierros Dec 2021

Direct Foam Writing In Microgravity, Guy Jacob Cordonier, Cicely Sharafati, Spencer Mays, Lukas Thackery, Ellena Gemmen, Samuel Cyphert, Megan Brown, John Quinn Napolillo, Savannah Toney, Hunter Moore, John M. Kuhlman `, Konstantinos A. Sierros

Faculty & Staff Scholarship

Herein we report 2D printing in microgravity of aqueous-based foams containing metal oxide nanoparticles. Such hierarchical foams have potential space applications, for example for in situ habitat repair work, or for UV shielding. Foam line patterns of a TiO2-containing foam have been printed onto glass substrates via Direct Foam Writing (DFW) under microgravity conditions through a parabolic aircraft flight. Initial characterization of the foam properties (printed foam line width, bubble size, etc.) are presented. It has been found that gravity plays a significant role in the process of direct foam writing. The foam spread less over the substrate when deposited …

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State-Of-The-Art Of Thermal Control Solutions To Establish A Modular, Multi-Orbit Capable Spacecraft Thermal Management System Design Methodology, Robert C. Consolo Jr Dec 2021

State-Of-The-Art Of Thermal Control Solutions To Establish A Modular, Multi-Orbit Capable Spacecraft Thermal Management System Design Methodology, Robert C. Consolo Jr

Doctoral Dissertations and Master's Theses

Today, the exploration and exploitation of space continues to become a more common occurrence. All types of spacecraft (S/C) utilize various types of thermal management solutions to mitigate the effects of thermal loading from the unforgiving vacuum of space. Without an appropriately designed thermal system, components on-board the S/C can experience failure or malfunction due to fluctuations in temperatures either beyond the designed operational parameters or unstable oscillating temperatures. The purpose of this study is to perform a comprehensive review of technologies available today that are being used for thermal management onboard S/C in addition to investigating the means to …

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Numerical Simulation Of A Cryogenic Spray, Neel Kishorkumar Shah Dec 2021

Numerical Simulation Of A Cryogenic Spray, Neel Kishorkumar Shah

Doctoral Dissertations and Master's Theses

Cryogenic sprays have many applications in modern engineering. Cooling of electronic equipment subject to high heat flows, surgical ablation of gastrointestinal mucosae or orbital maneuvering are a few examples of their versatility. However, the atomization of a cryogenic liquid is a complex process. During such an event, aerodynamic effects associated with secondary atomization are further affected by thermodynamic flashing. A better understanding of the characteristics of cryogenic sprays is then necessary to allow for improved design and optimization in applications. The overarching objective of this study is to document such characteristics. The numerical simulation was performed over cryogenic nitrogen spray …

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In-Situ Monitoring Of Additive Manufacturing Using Digital Image Correlation, Martina Jani Dec 2021

In-Situ Monitoring Of Additive Manufacturing Using Digital Image Correlation, Martina Jani

Doctoral Dissertations and Master's Theses

Advances in additive manufacturing over the past decade have led to applications in multiple fields. In particular, additive manufacturing answers the need for high flexibility in designing complex structures, however, the rapid thermal fluctuations during processing lead to numerous defects and processing-induced residual stresses. In this research, an in-situ approach using Digital Image Correlation (DIC) is developed to monitor the deformation during the processing, and thereby analyze the formation of defects and residual stresses. DIC is a visual technique that compares the changes in speckle pattern in consecutive images of a specimen to determine the displacements and strains. This research …

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Reduced-Order Dynamic Modeling And Robust Nonlinear Control Of Fluid Flow Velocity Fields, Anu Kossery Jayaprakash, William Mackunis, Vladimir Golubev, Oksana Stalnov Dec 2021

Reduced-Order Dynamic Modeling And Robust Nonlinear Control Of Fluid Flow Velocity Fields, Anu Kossery Jayaprakash, William Mackunis, Vladimir Golubev, Oksana Stalnov

Publications

A robust nonlinear control method is developed for fluid flow velocity tracking, which formally addresses the inherent challenges in practical implementation of closed-loop active flow control systems. A key challenge being addressed here is flow control design to compensate for model parameter variations that can arise from actuator perturbations. The control design is based on a detailed reduced-order model of the actuated flow dynamics, which is rigorously derived to incorporate the inherent time-varying uncertainty in the both the model parameters and the actuator dynamics. To the best of the authors’ knowledge, this is the first robust nonlinear closed-loop active flow …

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Kinematics Of Inter-Ply Interfaces In Composite Manufacturing, Sandeep Chava Dec 2021

Kinematics Of Inter-Ply Interfaces In Composite Manufacturing, Sandeep Chava

Doctoral Dissertations and Master's Theses

The ubiquitous usage of polymer matrix composites in many applications demands a comprehensive understanding of composite interfaces and processing induced residual stresses, which critically affect both the manufacturing processes and the deformation mechanisms. Processing induced residual stresses are often responsible for causing warping, delamination, and dimensional instability in composite structures. This research includes new in-situ experimental approaches, cure cycle design, interface modification, and thermomechanical modeling for developing a fundamental understanding of the cure kinetics during composite manufacturing. Strains, ply-movement, and formation of defects are observed in-situ using digital image correlation (DIC) during the autoclave cure cycle for the first time. …

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Development Of A Three Degree-Of-Freedom Control Simulation For A Group 3 Large Unmanned Aircraft System, Majka Anna Wilczynski Dec 2021

Development Of A Three Degree-Of-Freedom Control Simulation For A Group 3 Large Unmanned Aircraft System, Majka Anna Wilczynski

Theses and Dissertations

Aircraft modeling and simulation has become increasingly important in the aviation world. Simulations allow for safer and more economical training prior to flight testing. In this project, a three degree-of-freedom control simulation coded in a MATLAB environment is used to assess and simulate the dynamic stability of group three unmanned aircraft system. By calculating, evaluating, and simulating the static and dynamic stability derivatives of the aircraft, this project will allow for the estimation of the handling qualities of an unmanned aircraft system. This can help mitigate risks that come along with altering the mass and aerodynamic properties of an aircraft, …

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Enhancing Situational Awareness For Rotorcraft Pilots Using Virtual And Augmented Reality, Ardit Pranvoku Dec 2021

Enhancing Situational Awareness For Rotorcraft Pilots Using Virtual And Augmented Reality, Ardit Pranvoku

Theses and Dissertations

Rotorcraft pilots often face the challenge of processing a multitude of data, integrating it with prior experience and making informed decisions in complex, rapidly changing multisensory environments. Virtual Reality (VR), and more recently Augmented Reality (AR) technologies have been applied for providing users with immersive, interactive and navigable experiences. The research work described in this thesis demonstrates that VR/AR are particularly effective in providing real-time information without detracting from the pilot's mission in both civilian and military engagements. The immersion of the pilot inside of the VR model provides enhanced realism. Interaction with the VR environment allows pilots to practice …

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Utilizing Uas To Support Wildlife Hazard Management Efforts By Airport Operators, Flavio A. C. Mendonca, Ryan Wallace Dec 2021

Utilizing Uas To Support Wildlife Hazard Management Efforts By Airport Operators, Flavio A. C. Mendonca, Ryan Wallace

Publications

The FAA requires airports operating under the Code of Federal Regulations Part 139 to conduct a wildlife hazard assessment (WHA) when some wildlife-strike events have occurred at or near the airport. The WHA should be conducted by a Qualified Airport Wildlife Biologist (QAWB) and must contain several elements, including the identification of the wildlife species observed and their numbers; local movements; daily and seasonal occurrences; and the identification and location of features on and near the airport that could attract wildlife. Habitats and land-use practices at and around the airport are key factors affecting wildlife species and the size of …

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Lupa: An Excursion Vehicle For The Moons Of Mars, Shannon Kavanagh, Bo Lewis, Alex Odinamba, Joshua Mulhern Dec 2021

Lupa: An Excursion Vehicle For The Moons Of Mars, Shannon Kavanagh, Bo Lewis, Alex Odinamba, Joshua Mulhern

Senior Design Project For Engineers

Our team has designed a spacecraft and mission for exploring the moons of Mars. The Lithological and Ultraviolet Photometry Assessment (LUPA) excursion vehicle is capable of crew habitation, autonomous rendezvous, and in-vacuum sample collection all in support of a parallel Mars surface mission to be carried out in the year 2040. Our project's key focus areas revolve around orbital mechanics, space vehicle propulsion analysis, scientific exploration, and the management of various interconnected spacecraft subsystems.

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Project Scrappie (Clear Constellation), Jacob Bertram, Jacob Britt, Bill Ngo, Mike Diesing Dec 2021

Project Scrappie (Clear Constellation), Jacob Bertram, Jacob Britt, Bill Ngo, Mike Diesing

Senior Design Project For Engineers

Clear Constellation™ is a nationwide competition hosted by Rubicon® to combat the growing problem of space debris in Low Earth Orbit. Project Scrappie is our team’s solution to this problem. Scrappie is an autonomous apparatus will make use of Whipple shield technology to collide with debris at high velocities and effectively destroy the debris throughout selected orbital paths.

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Stress Intensity Factor - Simple Solution For A Complex Problem, Hamid A. Ghassri, Alberto Mello Dec 2021

Stress Intensity Factor - Simple Solution For A Complex Problem, Hamid A. Ghassri, Alberto Mello

Beyond: Undergraduate Research Journal

This research explores the modeling of a cracked structure using a linear elastic finite element method (FEM) analysis with the objective of determining the stress intensity factor (SIF) for complex geometries. The analysis uses a mapping of the stress concentration area ahead of the crack tip to asymptotically determine the SIF. For model calibration, Irwin’s approximation method was used in two known crack case solutions subjected to a uniform tensile loading (Mode I – Opening) with fixed geometric dimensions. With focus on aircraft airworthiness application, two more complex geometries with irregular stress distributions were analyzed and the results were extracted …

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A Numerical Study Of Water Entry Problems Based On Overset Meshes, Yanni Chang Dec 2021

A Numerical Study Of Water Entry Problems Based On Overset Meshes, Yanni Chang

Mechanical and Aerospace Engineering Dissertations - Archive

A series of numerical experiments carried out on the water entry of circular cylinders are presented in this study. A cylinder was entering into the water with a prescribed inclined angle and velocity. The interface between water and air is tracked by the Piecewise Linear Interface Calculation (PLIC) schemes in conjunction with the Volume of Fluid (VOF) method. PLIC schemes have been extensively employed in the VOF method for interface capturing in numerical simulations of multiphase flows. Dynamic overset meshes, which have been widely used for problems with relative motions and complex geometric shapes, are applied to handle the moving …

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Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal Dec 2021

Characterization And Enhancement Of Fatigue And Fracture Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Manjarik Mrinal

Mechanical and Aerospace Engineering Dissertations - Archive

Fused filament fabrication (FFF) show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. This happens due to the poor interlaminar bonding between the layers, as a result of premature halt of bond healing process. Previous research works show multiple approaches to improve the bond quality to enhance the mechanical properties of FFF parts, however these are complex and expensive techniques. In this work a novel print head assembly is presented to offer a simple and effective solution by applying a thermal field to the part as it is being printed to preheat the previously deposited layer, …

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Internal Pressure Response Of A Human Head Surrogate Model Subject To Variable Impact Loading With Finite Element Analysis, Aaron Ronald Jackson Dec 2021

Internal Pressure Response Of A Human Head Surrogate Model Subject To Variable Impact Loading With Finite Element Analysis, Aaron Ronald Jackson

Mechanical and Aerospace Engineering Theses - Archive

Traumatic brain injury (TBI) from blunt impacts to the head is a major cause of brain disease and dysfunction for thousands of people every year. Each year in the United States approximately 1 million TBI cases occur causing as many as 56,000 deaths and leaving nearly 90,000 individuals with long-term disabilities. Damage resulting from a TBI occurs on a multiscale level including the macroscopic, tissue, and neuron length scale. This research focuses on correlating the macroscopic blunt impact conditions to the internal pressure developed in the coup and countercoup for water and gelatin-filled head models. Two separate 3D printed models …

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Synthesis And Characterization Of Graphene-Reinforced Polymer Filaments For Additive Manufacturing, Sean Menezes Dec 2021

Synthesis And Characterization Of Graphene-Reinforced Polymer Filaments For Additive Manufacturing, Sean Menezes

Mechanical and Aerospace Engineering Theses - Archive

Fused Deposition Modeling (FDM) is a popular 3D printing process which uses a spool of thermoplastic polymer filament that is melted by the movable extruder printer head onto the bed to generate the required shape. The most used polymer filaments in FDM are Acrylonitrile Butadiene Styrene (ABS) and Poly Lactic Acid (PLA). However, these conventional polymer filaments have lower mechanical strength and are more susceptible to cracking as the cooler parts of the printed part shrink so much that they cause cracks to develop, leading to warping. The current investigation focuses on the synthesis of graphene, synthesis of polymer filaments …

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Reverse Engineering To Create High Quality Polymer Parts Using Additive Manufacturing, Gurtej Singh Tarsem Singh Channa Dec 2021

Reverse Engineering To Create High Quality Polymer Parts Using Additive Manufacturing, Gurtej Singh Tarsem Singh Channa

Mechanical and Aerospace Engineering Theses - Archive

Reverse engineering is a process of recreating parts for which the tools no longer exist, reducing the cost of an original part by manufacturing it in-house or redesigning and improving the original part's function. This research demonstrates two methods to reverse engineer a part using Polyworks software, having it printed using an SLS printer and checking the accuracy of the printed part to the original scan. The part is first scanned using a Faro-Arm laser scanner to obtain the point cloud data. The two methods used to recreate and extract the STEP file are: • Exporting NURBS. • Exporting Features …

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Development Of The Vehicle Configuration Compendium: A Comprehensive Data-Information-Knowledge System To Aid In High-Speed Vehicle Design, Stenila Simon Dec 2021

Development Of The Vehicle Configuration Compendium: A Comprehensive Data-Information-Knowledge System To Aid In High-Speed Vehicle Design, Stenila Simon

Mechanical and Aerospace Engineering Theses - Archive

The conceptual design phase is the most crucial phase in hypersonic vehicle design. Choices made during this phase will have significant impact on the success of the overall project and the feasibility of the end-product. Therefore, it is of utmost importance for the design decision-maker to be adequately informed of past-to-present projects throughout the aerospace community and lessons learned from them. This avoids wasting valuable time and resources for reinventing the wheel. There currently exists no one-stop solution in the aerospace industry to address the issue of lost data, information and knowledge in the field of high-speed vehicle design. The …

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Relating Linear And Rotational Accelerations With Internal Pressures Developed Inside Human Head Surrogate Models, Arthur Thomas Koster Dec 2021

Relating Linear And Rotational Accelerations With Internal Pressures Developed Inside Human Head Surrogate Models, Arthur Thomas Koster

Mechanical and Aerospace Engineering Theses - Archive

Traumatic Brain Injury (TBI) is a chronic disease process that is difficult to both detect and treat. TBI can result from blast, kinetic, sonic, and electromagnet energy sources. This research focuses on correlating the bulk acceleration of a human-like head model to the localized internal pressure developed in the coup and contrecoup regions due to variable impact loading. Damage resulting in a TBI occurs on a multiscale level from the macroscale down to the damage of each individual neuron. Obtaining a relationship between bulk acceleration and localized internal pressure will allow for further correlation to the damage done on these …

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Investigation Of Heat Transfer Performance Of Double Pipe Counter-Flow Heat Pipe Using Three Fluids Water, Dowtherm, And Water-Based Nanofluid, Alaa Abed Harchan Al Hasseun Dec 2021

Investigation Of Heat Transfer Performance Of Double Pipe Counter-Flow Heat Pipe Using Three Fluids Water, Dowtherm, And Water-Based Nanofluid, Alaa Abed Harchan Al Hasseun

Mechanical and Aerospace Engineering Theses - Archive

Heat pipes are two-phase devices, capable of converting a significant amount of energy with low losses. They have been used in several applications such as systems thermal control and cooling. The purpose of the present work is to investigate the thermal performance of a double pipe counterflow against the fluid type. The pipe is divided into three zones including evaporator, adiabatic, and condenser zones. All thermal boundary conditions are defined in terms of heating or cooling temperatures in which the operating temperatures are defined between 303 K to 470 K. using Ansys Fluent, the pipe is analyzed in two-and three-dimensional …

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Prediction Of Solder Joint Fatigue Life Of Photonic Package Using ?-? Materials, Ojas Tyagi Dec 2021

Prediction Of Solder Joint Fatigue Life Of Photonic Package Using ?-? Materials, Ojas Tyagi

Mechanical and Aerospace Engineering Theses - Archive

Fatigue life prediction has become very important factor in reliability of any electronic components to withstand extreme thermal stresses in industrial standard. Hence, photonic packages are widely used in telecommunication and computer applications. The primary focus of this study is to determine the thermal cycles to crack initiation of solder bump used in laser array waferboard for telecommunication applications. This includes GaAs Laser chip on waferboard and Si substrate with pure Indium solder balls in between. Indium has proved higher fatigue life in various experimental studies in the field of reliability and lead-free material. Therefore, a solder ball was designed …

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Analysis Of Blood Pressure Waveform For Detection And Diagnosis Of Cardiovascular Anomalies, Atul Shrotriya Dec 2021

Analysis Of Blood Pressure Waveform For Detection And Diagnosis Of Cardiovascular Anomalies, Atul Shrotriya

Mechanical and Aerospace Engineering Theses - Archive

Cardiovascular diseases are the leading cause of mortalities worldwide as well as in the United States. Early diagnosis and prediction of these diseases is critical to mitigate the risks to the patient. A common method to assess a person’s heart health is through the use of cuff type oscillometric devices placed on the arm of the patient. As the mean pressure in the cuff is increased the blood flow in the brachial artery becomes blocked. When the cuff pressure is reduced the blood starts flowing again; during this cycle, pressure fluctuations in the cuff are measured using a pressure transducer. …

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