Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Mechanical Engineering (3229)
- Space Vehicles (1867)
- Aerodynamics and Fluid Mechanics (1219)
- Navigation, Guidance, Control and Dynamics (1183)
- Aeronautical Vehicles (1102)
-
- Physical Sciences and Mathematics (1036)
- Electrical and Computer Engineering (865)
- Systems Engineering and Multidisciplinary Design Optimization (853)
- Other Aerospace Engineering (852)
- Structures and Materials (797)
- Propulsion and Power (743)
- Aviation (682)
- Astrodynamics (614)
- Social and Behavioral Sciences (522)
- Public Affairs, Public Policy and Public Administration (397)
- Systems and Communications (382)
- Aviation and Space Education (363)
- Materials Science and Engineering (332)
- Science and Technology Studies (325)
- Physics (317)
- Defense and Security Studies (296)
- Nuclear Engineering (296)
- Political Science (295)
- International and Area Studies (285)
- International Relations (284)
- Leadership Studies (284)
- Computer Sciences (282)
- Asian Studies (275)
- Institution
-
- Air Force Institute of Technology (1662)
- Embry-Riddle Aeronautical University (1197)
- Missouri University of Science and Technology (1154)
- University of Texas at Arlington (953)
- California Polytechnic State University, San Luis Obispo (755)
-
- Utah State University (692)
- Old Dominion University (596)
- Morehead State University (499)
- University of Alabama in Huntsville (337)
- Ohio University (336)
- University of Nebraska at Omaha (317)
- Purdue University (249)
- University of Central Florida (213)
- University of Kentucky (175)
- Florida Institute of Technology (138)
- Western Michigan University (120)
- University of Nebraska - Lincoln (101)
- West Virginia University (95)
- The University of Akron (86)
- Michigan Technological University (83)
- University of Texas at El Paso (82)
- Tashkent State Technical University (56)
- Minnesota State University, Mankato (52)
- University of Nevada, Las Vegas (49)
- University of Dayton (48)
- University of Arkansas, Fayetteville (45)
- University of South Carolina (45)
- Kennesaw State University (42)
- Washington University in St. Louis (42)
- George Fox University (34)
- Keyword
-
- #antcenter (183)
- Aerodynamics (152)
- CFD (125)
- Additive manufacturing (118)
- UAV (118)
-
- #csra (115)
- Optimization (101)
- Computational fluid dynamics (92)
- Aircraft (88)
- CubeSat (85)
- Applied sciences (79)
- Simulation (79)
- Composites (78)
- Aerospace (77)
- Turbulence (77)
- Aviation (73)
- Propulsion (68)
- Spacecraft (68)
- Flight control (56)
- Combustion (54)
- Control (53)
- Fluid dynamics (53)
- Computational Fluid Dynamics (52)
- Machine learning (52)
- Finite element method (51)
- Navigation (51)
- Optimal Control (51)
- Airplanes (50)
- Composite materials (50)
- Satellite (46)
- Publication Year
- Publication
-
- Theses and Dissertations (1770)
- Mechanical and Aerospace Engineering Faculty Research & Creative Works (812)
- Mechanical and Aerospace Engineering Theses - Archive (683)
- Robert "Bob" Twiggs STEM Education Collection (475)
- Doctoral Dissertations and Master's Theses (474)
-
- Mechanical & Aerospace Engineering Theses & Dissertations (385)
- Master's Theses (366)
- Online Journal of Space Communication (336)
- Aerospace Engineering (278)
- Space and Defense (278)
- Mechanical and Aerospace Engineering Dissertations - Archive (255)
- Space Dynamics Laboratory Publications (175)
- Small Satellite Conference (161)
- Master's Theses - Daytona Beach (159)
- Masters Theses (156)
- Publications (150)
- International Journal of Aviation, Aeronautics, and Aerospace (138)
- Faculty Publications (118)
- Von Braun Symposium Student Posters (113)
- Electronic Theses and Dissertations (106)
- Space Journal (102)
- Discovery Day - Daytona Beach (99)
- All Graduate Theses and Dissertations, Spring 1920 to Summer 2023 (98)
- Mechanical and Aerospace Engineering Faculty Publications (86)
- Williams Honors College, Honors Research Projects (86)
- Open Access Theses (83)
- Open Access Theses & Dissertations (82)
- Electronic Theses and Dissertations, 2020-2023 (66)
- Graduate Theses, Dissertations, and Problem Reports (ETD) (64)
- Theses and Dissertations--Mechanical and Aerospace Engineering (64)
- Publication Type
- File Type
Articles 3031 - 3060 of 11100
Full-Text Articles in Aerospace Engineering
Unmanned Aircraft Systems For Archaeology Using Photogrammetry And Lidar In Southwestern United States, Imai Bates-Domingo, Alexandra Gates, Patrick Hunter, Blake Neal, Kyle Snowden, Destin Webster
Unmanned Aircraft Systems For Archaeology Using Photogrammetry And Lidar In Southwestern United States, Imai Bates-Domingo, Alexandra Gates, Patrick Hunter, Blake Neal, Kyle Snowden, Destin Webster
Study America
Researchers can use small unmanned aircraft systems (sUAS), also known as drones, to make observations of historical sites, help interpret locations, and make new discoveries that may not be visible to the naked eye. A student team from Embry-Riddle Aeronautical University gathered data for historical site documentation in New Mexico using the DJI Phantom 4 Pro V2, DJI Mavic Pro 2, DJI M210 and DJI M600, and senseFly eBee. Utilizing these drones, student analysts were able to take the data gathered and create georectified orthomosaic images and 3D virtual objects. At Tularosa Canyon, at a site known as the Creekside …
Radiation Effects On Space Solar Cells At Various Earth And Jupiter Orbital Altitudes, Naazneen Rana
Radiation Effects On Space Solar Cells At Various Earth And Jupiter Orbital Altitudes, Naazneen Rana
Discovery Undergraduate Interdisciplinary Research Internship
Solar cells are used as the primary power source for earth-orbiting satellites and as a primary/secondary power source for various missions within the solar system. However, high energy particles from the sun, planetary magnetospheres, and the galaxy can affect the performance and life expectancy of the space solar cell and associated power systems. As the interests for interplanetary travel and the exploration of planets within our solar system increase, the need to understand a device’s performance within a particular planet’s environment is necessary. Therefore, this study will analyze the performance of space solar cells, particularly the SolAero IMM-α, at various …
Stress Analysis Of Functionally Graded Materials, Nilabh Krishna
Stress Analysis Of Functionally Graded Materials, Nilabh Krishna
Mechanical and Aerospace Engineering Dissertations - Archive
A functionally graded material (FGM) is an inhomogeneous material whose material properties vary continuously. Since FGM’s material properties are continuous at the interface of the two materials, unlike conventional composites whose material properties are discontinuous at the interface, it is best suited to prevent catastrophically failure, stress concentration, and residual stresses. Literature reviews revealed that most of the research on FGMs was a 2-D analysis, especially on FGM plates and beams. This research focuses on 3-D stress analysis for an elastic medium that contains a spherical inclusion made of an FGM embedded in a matrix phase. To the best of …
Effect Of Thermal Conductivity, Reynolds Number, Aspect Ratio And Packing Arrangement On Radial Heat Transfer In Packed Beds, Nishith Gorla
Effect Of Thermal Conductivity, Reynolds Number, Aspect Ratio And Packing Arrangement On Radial Heat Transfer In Packed Beds, Nishith Gorla
Mechanical and Aerospace Engineering Dissertations - Archive
The key motivation for this research is to study heat transfer developments in packed beds. The radial heat transfer enhancement of a packed bed in the laminar flow region is one of the major areas of ongoing research in mechanical, aerospace and chemical industries, especially the response of a packed bed during conjugate heat transfer with the fluid-solid interaction. This computational study focuses on the impact of packing size, thermal conductivity, and arrangement on the radial heat transfer performance as a function of Reynolds number. A simple annular tube packed with circles (2D) and spheres (3D) is utilized for this …
Modeling The Effect Of In Situ Nozzle-Integrated Compression Rolling On The Mechanical And Fracture Behavior Of Fused Filament Fabrication (Fff) 3d Printed Parts, Momen Mohammad Qasaimeh
Modeling The Effect Of In Situ Nozzle-Integrated Compression Rolling On The Mechanical And Fracture Behavior Of Fused Filament Fabrication (Fff) 3d Printed Parts, Momen Mohammad Qasaimeh
Mechanical and Aerospace Engineering Dissertations - Archive
Fused filament fabrication (FFF) is one of the most common additive manufacturing/3D printing techniques where continuously extruded semi-molten filaments are deposited in a layer-by-layer manner. The quality of the manufactured part depends on some major factors such as filament-filament contact and adhesion as well as the void fraction. Filament to filament adhesion affects the part strength under transverse load. In our earlier work, we studied the effect of in situ ball rolling on the thermal and mechanical properties of the printed parts. It was found that when printing/rolling parameters are correctly tuned and in situ compression rolling is appropriately applied …
Set-Theoretic Frameworks For Online Optimization, Estimation, And Control, Dignata Bhattacharjee
Set-Theoretic Frameworks For Online Optimization, Estimation, And Control, Dignata Bhattacharjee
Mechanical and Aerospace Engineering Dissertations - Archive
This research is primarily focused on developing online frameworks, which are suited to real-time implementation, for performance optimization, estimation, and control of dynamical systems using set-theoretic concepts and/or having set-theoretic interpretations. First, two perturbation-based extremum seeking control schemes, based on the classical setup and equipped with novel adaptation laws for the perturbation signal amplitudes, are proposed for general single input single output nonlinear systems. The proposed schemes are able to extremize steady-state system output in a practical asymptotic sense, i.e., the system is driven to an arbitrarily small set centered at the true steady-state optimal operating point. The next development …
Uncertainty Propagation, Control, And Estimation Of Stochastic Dynamic Systems Using Generalized Polynomial Chaos Expansion, Rajnish Bhusal
Uncertainty Propagation, Control, And Estimation Of Stochastic Dynamic Systems Using Generalized Polynomial Chaos Expansion, Rajnish Bhusal
Mechanical and Aerospace Engineering Dissertations - Archive
In recent years, uncertainty propagation has emerged as an important research area in the field of dynamical systems. The growing interest in this area arises out of the need to develop computationally efficient approaches to predict the evolution of a system subject to uncertainties. To this end, this dissertation is focused on developing computational frameworks for uncertainty propagation, control, and state estimation of stochastic dynamical systems using the generalized polynomial chaos (gPC) expansion technique. In the first part of this dissertation, the construction of gPC expansion is presented in general. The novelty of this dissertation lies in developing a mixed …
Computational Investigation Of Energy Dissipation Through Progressive Failure In Tailored Composite Structures Via Explicit Finite Element Analysis, Anirudh Srinivas
Computational Investigation Of Energy Dissipation Through Progressive Failure In Tailored Composite Structures Via Explicit Finite Element Analysis, Anirudh Srinivas
Mechanical and Aerospace Engineering Dissertations - Archive
In this study, energy dissipation in structures implementing a previously developed, analytically modeled, and experimentally validated composite tailoring concept is investigated using an explicit finite element approach. The tailored composite structures consist in a series connection of parallel alternate load paths of tailored length and thickness. The advantage of the tailored structure when compared to an untailored conventional structure is that when subjected to a tensile load, the response of the tailored composite structure is characterized by progressive failure of the load paths resulting in increased energy dissipation. The tailored composite structure is modeled for IM7-8552 composite material using a …
Laminar Swept And Cross Shockwave/Boundary-Layer Interactions, Jiss Jacob Sebastian
Laminar Swept And Cross Shockwave/Boundary-Layer Interactions, Jiss Jacob Sebastian
Mechanical and Aerospace Engineering Dissertations - Archive
Shockwave/boundary-layer interactions are considered one of the most complex problems in high-speed gas dynamics, and numerous studies have been carried out for more than eighty years to understand the fundamental physics. A numerical study was performed using fin-plate configurations to study the three-dimensional swept and cross shockwave/ laminar boundary-layer interactions. All the interactions studied were strong enough for the boundary layer to separate. In the first part, swept shock interactions between a laminar boundary layer and the shockwave induced by a sharp fin mounted perpendicularly on a flat plate were studied. Different flow conditions were investigated at freestream Mach numbers …
Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth
Design, Operation And Maintenance Of Direct And Indirect Evaporative Cooling Systems In Data Center Thermal Management, Ashwin Siddarth
Mechanical and Aerospace Engineering Dissertations - Archive
Evaporative cooling is an alternative data center cooling solution that presents significant energy cost savings in acquisition and operation when compared to conventional air conditioning and mechanical refrigeration systems. This research focuses on developing a deeper understanding in implementing, operating and maintaining evaporative cooling systems integrated with air-side economization to realize the energy savings potential in data center cooling. The goal of the research is to develop a comprehensive guide to assess and contrast different approaches of evaporative cooling being used in data center cooling and provide guidance in improving water and energy efficiency. An air handling unit (AHU) serves …
Design Of Streamline-Traced Inlets And Their Integration With Rotating Detonation Engines, Malcolm Lee Branch
Design Of Streamline-Traced Inlets And Their Integration With Rotating Detonation Engines, Malcolm Lee Branch
Mechanical and Aerospace Engineering Theses - Archive
This thesis has two parts: 1) design of the streamline-traced inlets (STIs); and 2) integration of STIs with rotating detonation engines (RDEs). The STI design starts with a two-dimensional, isentropic compression flowfield as the parent flowfield. The method of characteristics was used to generate the flowfield throughout the entire STI. For a given flight altitude 18 km, freestream Mach number M?=3.0, and inlet exit-plane Mach number M?=1.2, a parametric sweep of the initial deflection angle ?1=4.0--11.0 deg and the Mach number at the entrance of the internal compression system M3=1.3--1.7 was performed to determine the STI performance sensitivity as a …
Haptic Interface Optimization For Virtual Anastomosis Surgery Training, Kangji Huang
Haptic Interface Optimization For Virtual Anastomosis Surgery Training, Kangji Huang
Mechanical and Aerospace Engineering Theses - Archive
Virtual anastomosis surgery study allows surgeons to perform or practice suturing in virtual reality using a commercial haptic device. The haptic device can generate force feedback so that the user can feel the real touch sensation of the object in virtual reality. The virtual anastomosis surgery study has two requirements which are that the haptic device must be fixed on the operating table and haptic device location must be suitable for different surgeons. The goal is to use a commercially available haptic device for this purpose, rather than design a new device for each possible surgery that must be performed. …
Design And Cfd Analysis Of Bimetallic Based Passive Dynamic Cold Plate For High Power Direct-To-Chip Liquid Cooling, Apurv Pravin Deshmukh
Design And Cfd Analysis Of Bimetallic Based Passive Dynamic Cold Plate For High Power Direct-To-Chip Liquid Cooling, Apurv Pravin Deshmukh
Mechanical and Aerospace Engineering Theses - Archive
Rising demand for high-performance chips results in the need for advanced and efficient cooling technologies like direct to chip liquid cooling. Cold plates based utilizing direct liquid cooling is one of the most efficient and the most investigated cooling technology since the 1980s. Major data services and cloud providers like IBM, Microsoft, and Google had already started a shift towards liquid-cooled data centers for their high computational servers. At the chip level nowadays, the processors are divided into several cores and each of these cores continuously works at varying computational demands. This creates a non-uniform heat distribution across the processor, …
Simulation Of A Soft Body Non-Grasp Manipulator Using A Spring-Mass-Damper Cloth Model, Cristian Almendariz
Simulation Of A Soft Body Non-Grasp Manipulator Using A Spring-Mass-Damper Cloth Model, Cristian Almendariz
Mechanical and Aerospace Engineering Theses - Archive
Simulation and modeling are well known and important tools in the field of robotics, being used to validate design and in the development of robotic control systems. Traditionally, robotic systems have been primarily rigid body systems and used in well controlled environments where interactions are highly predictable, and exceptions are minimized. With the ever-increasing adoption of robotics in the medical field, typical robotic environments are becoming highly unpredictable and requiring the modeling and simulation of not only rigid body systems but soft systems and interactions between the two. This work addresses model improvement of a “soft and hard” robotic system …
Development Of Virtual Simulation For Evaluation Of Robotic Assistive Environment, Shubham Raosaheb Gunjal
Development Of Virtual Simulation For Evaluation Of Robotic Assistive Environment, Shubham Raosaheb Gunjal
Mechanical and Aerospace Engineering Theses - Archive
Robotics research in virtual simulation has the advantage of reduced testing time, verification of algorithms on different systems before implementation, and cost-saving. Today’s simulation softwares are capable of providing the physics of the simulation such as torque requirements of the joints which aid in the selection of appropriate hardware. In this research, Webots, an open-source physics-based simulation, and visualization software is evaluated and then used to study and evaluate the performance of two robotic systems for a robotic assistive environment for persons with upper limb disabilities. This includes a wheelchair, a table with objects, and two robotic arms attached to …
Investigating A Finite Element Model Updating Methodology For Characterizing Mechanical Properties Of Ncf Composites, Pasworn Chanchai
Investigating A Finite Element Model Updating Methodology For Characterizing Mechanical Properties Of Ncf Composites, Pasworn Chanchai
Mechanical and Aerospace Engineering Theses - Archive
Composite materials have been a key breakthrough in developing aircraft structures. Their superior strength and stiffness-to-density ratio, which are unmatched by no other materials, allow engineers to create high strength and ultra-lightweight aircraft structures. Recently, non-Crimp Fabric (NCF) composites have emerged as attractive alternatives to traditional autoclave pre-impregnated composites allowing for lower production costs, better handling and improved shelf life while maintaining excellent in-plane mechanical properties compared to other types of textile composites. NCF out-of-plane mechanical properties can also be enhanced by stitching a high tensile strength yarn throughout their entire laminate thickness, improving the resistance to delamination. However, stitch-reinforced …
Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane
Characterization And Enhancement Of Mechanical Properties In Thermoplastic Fff Parts Using In-Situ Annealing, Rhugdhrivya Rane
Mechanical and Aerospace Engineering Dissertations - Archive
Fused filament fabrication is one of the most common and widely used additive manufacturing techniques. Owing to its ease of use, availability and cheap feedstock it provides a significant advantage over other AM techniques. But these advantages are overshadowed by the fact that FFF parts show high anisotropy and reduced mechanical properties as compared to conventional manufacturing techniques. Literature review of previous research works show multiple approaches to enhance the mechanical properties of FFF parts but each of these techniques have limitations to either the geometries that can be printed or involve complex expensive setups. In one such technique a …
Shape Modeling, Attitude Estimation, And Classification Of Artificial Resident Space Objects (Rso) Using Photometric Light Curves, Katiyayni Balachandran
Shape Modeling, Attitude Estimation, And Classification Of Artificial Resident Space Objects (Rso) Using Photometric Light Curves, Katiyayni Balachandran
Mechanical and Aerospace Engineering Dissertations - Archive
Light curve inversion (LCI) has proven valuable in using photometric measurements to optimize various physical parameters of a resident space object (RSO) such as rotational period about its own spin axis, pole orientation and others. Other characteristics such as shape and size are dependent on the surface brightness. To accurately determine size, shape, spin rate, or attitude information of an unresolved resident space object, photometry is required to capture the relatively rapid changes in brightness that these objects can exhibit. LCI has been developed significantly for asteroids, although not fool-proof for artificial RSOs. Satellites and space debris, unlike asteroids, are …
Theoretical And Experimental Analysis And Optimization Of Thermal Conduction In Electrochemical And Latent Heat Energy Storage Systems, Amirhossein Mostafavi
Theoretical And Experimental Analysis And Optimization Of Thermal Conduction In Electrochemical And Latent Heat Energy Storage Systems, Amirhossein Mostafavi
Mechanical and Aerospace Engineering Dissertations - Archive
Phase change materials (PCMs) are used commonly for energy storage purposes. Thermal energy can be stored in a PCM with a variety of configurations such as PCM slabs, cartesian and cylindrical finned systems. Heat transfer in PCM storage systems can be from a heat transfer fluid (HTF) or a heat source at constant temperature to adjacent PCM. The rate of heat transfer is limited by thermal properties. Fin insertion can improve the heat transfer inside the PCM. Chapters 2 and 3 derive and solve the governing energy equations to determine the transient temperature distribution in the PCM due to the …
Rotor Performance Model (Rpm), Chadwick Scott Balfantz
Rotor Performance Model (Rpm), Chadwick Scott Balfantz
Mechanical and Aerospace Engineering Theses - Archive
Rotorcraft performance modeling is of high interest with multiple industry codes in existence, many of which are high-fidelity and are comprehensive in the analyses that are achievable. Along with the high-fidelity and the comprehensive nature of the industry codes comes an equally high level of complexity in the inputs required to extract meaningful results. The ever-increasing fidelity in the existing codes creates a need for an analysis code that is built to be highly flexible, designed from the top down and implemented from the bottom up in a structured format. The Rotor Performance Model (RPM) was developed to provide high-fidelity …
Interior Point Optimization Of Low-Thrust Spacecraft Trajectories, Jordan D. Frederiksen
Interior Point Optimization Of Low-Thrust Spacecraft Trajectories, Jordan D. Frederiksen
Master's Theses
Low-thrust interplanetary spacecraft trajectory optimization poses a uniquely difficult problem to solve because of the inherent nonlinearities of the dynamics and constraints as well as the large size of the search space of possible solutions. Tools currently exist that optimize low-thrust interplanetary trajectories, but these tools are rarely openly available to the public, and when they are available they require multiple interfaces between multiple different packages. The goal of this work is to present a new piece of low-thrust interplanetary spacecraft trajectory optimization software that is open-source and entirely self-contained so that more people can have access to the ability …
Integral Boundary Layer Methods In Python, Malachi Joseph Edland
Integral Boundary Layer Methods In Python, Malachi Joseph Edland
Master's Theses
This thesis presents a modern approach to two Integral Boundary Layer methods implemented in the Python programming language. This work is based on two 2D boundary layer methods: Thwaites' method for laminar boundary layer flows and Head's method for turbulent boundary layer flows. Several novel enhancements improve the quality and usability of the results. These improvements include: a common ordinary differential equation (ODE) integration framework that generalizes computational implementations of Integral Boundary Layer methods; the use of a dense output Runge-Kutta ODE solver that allows for querying of simulation results at any point with accuracy to the same order as …
Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu
Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu
PRC-Affiliated Research
Low-temperature, atmospheric pressure plasma presents a new, inexpensive, and environmentally friendly method of water purification. For long duration crewed space missions, a novel water purification system that does not rely on consumable filters and chemicals would be desirable. Plasma systems provide a viable option for these missions, but their operation and designs need to be optimized and compared to existing technology. For this application, gas and power usage are key limiting factors. In this work, water contaminated with methylene blue is purified with plasma. The rate of purification, gas flow usage, and power consumption are compared for multiple devices. A …
Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu
Plasma-Based Water Purification For Crewed Space Missions: Laboratory Experimental Comparisons For On-Board Applicability, Ryan P. Gott, Sydney D. Miller, Josie C. Hodges, Kunning G. Xu
PRC-Affiliated Research
Low-temperature, atmospheric pressure plasma presents a new, inexpensive, and environmentally friendly method of water purification. For long duration crewed space missions, a novel water purification system that does not rely on consumable filters and chemicals would be desirable. Plasma systems provide a viable option for these missions, but their operation and designs need to be optimized and compared to existing technology. For this application, gas and power usage are key limiting factors. In this work, water contaminated with methylene blue is purified with plasma. The rate of purification, gas flow usage, and power consumption are compared for multiple devices. A …
Object Classication, Detection And State Estimation Using Yolo V3 Deep Neural Network And Sensor Fusion Of Stereo Camera And Lidar, Kamalkumar Bharatkumar Mehta
Object Classication, Detection And State Estimation Using Yolo V3 Deep Neural Network And Sensor Fusion Of Stereo Camera And Lidar, Kamalkumar Bharatkumar Mehta
Mechanical and Aerospace Engineering Theses - Archive
Real-time object classification, localization, and detection with region-based convolution neural network (R-CNN) require high computational power, or it consumes a tremendous amount of time with the use of the available onboard computer system. Therefore, either of those ways is not practical in real-time object detection. In contrast, the YOLO-v3 network, which stands for you only look once, that uses the YOLO algorithm seems to be practical in live object classification, localization, and detection, since the YOLO algorithm seems to work faster than the sliding window algorithm used by R-CNN. Sensor fusion in this context requires estimation and association of information …
Background Flow Influence On Impulsive Jet-Driven Micro Droplet Dispersal, Vaishak Thiruvenkitam
Background Flow Influence On Impulsive Jet-Driven Micro Droplet Dispersal, Vaishak Thiruvenkitam
Doctoral Dissertations and Master's Theses
Accurately predicting the airborne spread of infectious diseases is crucial in controlling the COVID19 pandemic today. Studies have shown the spread of expiratory droplets depends on ambient thermodynamic conditions and flow properties of the jet emitted by the activity. However, the droplet spread in conditions of background flow is not yet comprehensively understood. This study uses the Eulerian-Lagrangian model with k−ω turbulence modelling to simulate spread of particles and study the factors affecting it in a closed environment with a background flow. Respiratory activities are modeled as a non-isothermal jet of air with droplets suspended in them in a predetermined …
Active Control Of Coherent Structures In An Axisymmetric Jet, Michael Marques Goncalves
Active Control Of Coherent Structures In An Axisymmetric Jet, Michael Marques Goncalves
Doctoral Dissertations and Master's Theses
The primary objective of this work is to develop high-fidelity simulation model for jet noise control predictions and quantify the sound reduction when an external source frequency mode excitation is imposed on the jet flow. Whereas passive approaches using mixing devices, such as chevrons, have been shown to reduce low-frequency noise in jet engines, such approaches incur a performance penalty since they result in a reduced thrust. To avoid a performance penalty in reducing jet noise, the current work investigates a open-loop active noise control (ANC) system that utilizes a unsteady microjet actuator on the nozzle lip in the downstream …
Shape Optimization Of A Sandwich Composite Plate With Low-Velocity Impact Loading And Effect Of Finite Difference Sensitivity Analysis, Utsav Shah
Doctoral Dissertations and Master's Theses
The structural design of spacesuits is essential in an advancing future of both Lunar and Martian space exploration. A typical spacesuit is made of sandwich composite material and designed to withstand various pressure and loading conditions while also considering the safety and comfort of the astronauts. One of the critical load cases in spacesuit design is a low-velocity impact (LVI) which may occur due to tool drop and other similar scenarios. The objectives of this work were (a) to create a finite element (FE) model of a component of a spacesuit, (b) validation of the FE model through experiments, (c) …
Design, Development, And Testing Of Research Payloads On Various Suborbital Flight-Test Platforms, Vijay Vishal Duraisamy
Design, Development, And Testing Of Research Payloads On Various Suborbital Flight-Test Platforms, Vijay Vishal Duraisamy
Doctoral Dissertations and Master's Theses
With recent advances in the commercial space industry, suborbital payload launches have become more common and accessible to researchers actively seeking solutions for problems involving prolonged space travel and future missions to Moon and Mars. Suborbital payload missions compared to orbital launches are less expensive and offer faster turnaround times; however, the novelty of this domain provides unique challenges. This multidisciplinary research effort aims to tackle some of these challenges by detailing the design, development, and testing techniques followed in the successful launch and recovery of payload experiments in currently active and upcoming suborbital launch vehicles. The research methodology involves …
Durability And Damage Analysis Of Hybrid Multiscale Composites, Suma Ayyagari
Durability And Damage Analysis Of Hybrid Multiscale Composites, Suma Ayyagari
Doctoral Dissertations and Master's Theses
In this dissertation, an effort was carried out to enhance the mechanical performance of fiber reinforced composites (FRPs) by modification of the fibers’ surface morphologies. The effects of various surface alterations of a plain-woven carbon fiber fabric surface, on the fiber/epoxy interface were investigated. The alterations were mostly achieved by growing different nanofillers like zinc oxide nanorods (ZnO NR), carbon nanotubes (CNTs), and metal organic frameworks (MOFs) on the fiber surface. While the growth techniques for ZnO NR and CNTs place restrictions on the size of the fabricated composites, MOFs route is uniform, affordable, and can be readily scaled up …