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Sound Propagation In Viscous Flows Using Piezoelectric Sensors And Non-Destructive Propagation Techniques And Its Applications, ahmed M. abdulkareem 2020 Virginia Commonwealth University

Sound Propagation In Viscous Flows Using Piezoelectric Sensors And Non-Destructive Propagation Techniques And Its Applications, Ahmed M. Abdulkareem

Theses and Dissertations

Structural non-destructive evaluation techniques are applied to viscous flows to detect fluid property changes. The main operating principle consists of an actuator which provides a stimulus, and a sensor to receive a signal traveling to a fluid domain. The main challenge of the operating principle consists of investigating waves traveling in a viscous flow. Traveling waves utilizing a piezoelectric actuator-sensor pair are modeled and the results are validated experimentally. ANSYS models, coupled with a two-way fluid-solid interaction model, are built to investigate how far a signal travels and what frequency ranges are of interest. The numerical model includes modeling three …


Bibliometric Analysis Of Bearing Fault Detection Using Artificial Intelligence, Pooja Kamat, Rekha Sugandhi Dr. 2020 Symbiosis Institute of Technology,Symbiosis International University, MITSOE, MIT-ADT University, Pune, India

Bibliometric Analysis Of Bearing Fault Detection Using Artificial Intelligence, Pooja Kamat, Rekha Sugandhi Dr.

Library Philosophy and Practice (e-journal)

The new industrial revolution called Industry 4.0 is proliferating at its peak. The time is no longer away when the human race is going to witness a huge paradigm shift. Intelligent machines empowered by Artificial Intelligence (AI)will take over the presence of human workers in the industrial manufacturing sector with the target of achieving 100% automation. With the emergence of cut-throat price competition in the product market, it has become equally important to manufacture goods at minimal costs and with the highest quality. Predicting the decrease in machinery efficiency at an earlier stage to accomplish this objective helps to reduce …


Theoretical Investigation Of The Low Frequency Fundamental Mechanism Of The Objective Occlusion Effect Induced By Bone-Conducted Stimulation, Kevin Carillo, Olivier Doutres, Franck Sgard 2020 Department of Mechanical Engineering, École de technologie supérieure

Theoretical Investigation Of The Low Frequency Fundamental Mechanism Of The Objective Occlusion Effect Induced By Bone-Conducted Stimulation, Kevin Carillo, Olivier Doutres, Franck Sgard

Études primaires

The objective occlusion effect induced by bone-conducted stimulation refers to the low frequency acoustic pressure increase that results from occluding the ear canal opening. This phenomenon is commonly interpreted as follows: the bone-conducted sound “leaks” through the earcanal opening and is “trapped” by the occlusion device. This instinctive interpretation misrepresents the fundamental mechanism of the occlusion effect related to the earcanal impedance increase and already highlighted by existing electro-acoustic models. However, these models simplify the earcanal wall vibration (i.e., the origin of the phenomenon) to a volume velocity source which, in the authors' opinion, (i) hinders an exhaustive comprehension of …


Accurate Replication Of An Ear Pinnae Geometry For Use In Acoustic Testing Of Spatial Cues And Sound Localization, Alejandra Belmont 2020 University of Texas at El Paso

Accurate Replication Of An Ear Pinnae Geometry For Use In Acoustic Testing Of Spatial Cues And Sound Localization, Alejandra Belmont

Open Access Theses & Dissertations

Additive manufacturing (AM) enables freedom of design as well as fabrication of complex objects such as the human hear. In medical modeling there is a need for patient-specific customizable parts. The outer human ear consists of these main parts: the pinna, which naturally filters sound, and the ear canal, which is the point at which sound enters before being moved up to the tympanic membrane, otherwise known as the eardrum. In an attempt to accurately replicate ear models, the use of scanning and reverse engineering methods was used. A comparison of 3D laser scanning systems was performed to determine their …


Development Of An Eco Approach And Departure Application To Improve Energy Consumption Of A Plug-In Hybrid Vehicle In Charge Depleting Mode, Brandon Narodzonek 2020 Michigan Technological University

Development Of An Eco Approach And Departure Application To Improve Energy Consumption Of A Plug-In Hybrid Vehicle In Charge Depleting Mode, Brandon Narodzonek

Dissertations, Master's Theses and Master's Reports

A recent study at Michigan Technological University as part of the NEXTCAR DOE APRA-E Project was conducted to determine the potential energy savings of a plug-in hybrid electric vehicle (PHEV) equipped with various Connected and Automated Vehicle (CAV) Technologies. One aspect of this study focused on the development of an Eco Approach and Departure (Eco AnD) Application that would further reduce the energy consumed around a signalized intersection.

Many modern intersections are equipped with traffic signals that can broadcast Basic Safety (BSM), MAP, and Signal Phase and Timing (SPaT) message sets that contain intersection ID, location, current phase, and cyclic …


Real-Time Predictive Control Of Connected Vehicle Powertrains For Improved Energy Efficiency, Joseph Oncken 2020 Michigan Technological University

Real-Time Predictive Control Of Connected Vehicle Powertrains For Improved Energy Efficiency, Joseph Oncken

Dissertations, Master's Theses and Master's Reports

The continued push for the reduction of energy consumption across the automotive vehicle fleet has led to widespread adoption of hybrid and plug-in hybrid electric vehicles (PHEV) by auto manufacturers. In addition, connected and automated vehicle (CAV) technologies have seen rapid development in recent years and bring with them the potential to significantly impact vehicle energy consumption. This dissertation studies predictive control methods for PHEV powertrains that are enabled by CAV technologies with the goal of reducing vehicle energy consumption.

First, a real-time predictive powertrain controller for PHEV energy management is developed. This controller utilizes predictions of future vehicle velocity …


Development Of High-Speed Photoacoustic Imaging Technology And Its Applications In Biomedical Research, Yun He 2019 Washington University in St. Louis

Development Of High-Speed Photoacoustic Imaging Technology And Its Applications In Biomedical Research, Yun He

McKelvey School of Engineering Graduate Student Theses & Dissertations

Photoacoustic (PA) tomography (PAT) is a novel imaging modality that combines the fine lateral resolution from optical imaging and the deep penetration from ultrasonic imaging, and provides rich optical-absorption–based images. PAT has been widely used in extracting structural and functional information from both ex vivo tissue samples to in vivo animals and humans with different length scales by imaging various endogenous and exogenous contrasts at the ultraviolet to infrared spectrum. For example, hemoglobin in red blood cells is of particular interest in PAT since it is one of the dominant absorbers in tissue at the visible wavelength.The main focus of …


Longitudinal Acoustic Traps: Design, Fabrication, And Evaluation For Biological Applications, Michael Moore Binkley 2019 Washington University in St. Louis

Longitudinal Acoustic Traps: Design, Fabrication, And Evaluation For Biological Applications, Michael Moore Binkley

McKelvey School of Engineering Graduate Student Theses & Dissertations

Acoustofluidics combine ultrasonic actuation with small-volume microfluidic channels to enable precise, contactless object manipulation for a range of applications from serial chemical processing to blood component separation and single-cell analysis. Micron- to millimeter-scale vibrational waves generate reproducible pressure fields within the microfluidic channels and chambers. By exploiting the material property mismatch between a particle (polymeric and silica beads, cells, etc.) and a suspending fluid, the acoustic radiation force is used to move particles toward regions of low (nodes) or high pressure (antinodes). An understanding of these field-particle interactions is applied to design and implement complicated channel architectures for preferential segregation …


The Investigation Of Noise, Vibrations And Emissions Of Aero-Gas Turbine Combustion With Synthetic Kerosene Fuels, Margaret Kilpatrick 2019 Georgia Southern University

The Investigation Of Noise, Vibrations And Emissions Of Aero-Gas Turbine Combustion With Synthetic Kerosene Fuels, Margaret Kilpatrick

Honors College Theses

Climatic changes from aviation emissions are complex and include effects of greenhouse gases such as: CO2, NOx, and aerosols. For that reason, the objectives of this study were to investigate the noise, vibrations and emissions characteristics of synthetic kerosene combustion in an aerospace gas turbine to reduce the engine’s environmental impact. Sustainably produced synthetic kerosene is known for having low soot emissions due to little to no aromatics (compounds that create particle pollutants), and for being a sustainable alternative fuel source to imported oil. The noise and sound levels were collected using Bruel & Kjaer microphones to measure various mid …


Ultrasonic Wave Propagation In Copper/Graphene Metal Matrix Composites, Casey Lindbloom 2019 University of Arkansas, Fayetteville

Ultrasonic Wave Propagation In Copper/Graphene Metal Matrix Composites, Casey Lindbloom

Mechanical Engineering Undergraduate Honors Theses

Emerging metallic composite materials implanted with graphene sheets are showing immense promise, with benefits being observed with regards to mechanical, thermal, and electrical material properties. This research aims to investigate the effects on ultrasonic wave propagation in Copper/Graphene Metal Matrix Composites (Cu/Gr MMCs) with varying graphene arrangements inspired from nacre and bone nanoscale material distributions. To accomplish this, the molecular dynamics (MD) method is utilized to simulate nanoscale wave propagation on a set of Cu/Gr MMCs with differing graphene arrangements and volume percentages ranging up to 4.56%. The computational model results are then analyzed to determine the variation in energy …


Dynamic Pressure Sensing For The Flight Test Data System, Marc Y. Goupil 2019 California Polytechnic State University - San Luis Obispo

Dynamic Pressure Sensing For The Flight Test Data System, Marc Y. Goupil

Master's Theses

This thesis describes the design, assembly, and test of the FTDS-K, a new device in the Boundary Layer Data System (BLDS) family of flight data acquisition systems. The FTDS-K provides high-frequency, high-gain data acquisition capability for up to two pressure sensors and an additional three low-frequency pressure sensors. Development of the FTDS-K was separated into a core module, specialized analog subsystem, and practical testing of the FTDS-K in a flow measurement mission. The core module combines an nRF52840-based microcontroller module, switching regulator, microSD card, real-time clock, temperature sensor, and trio of pressure sensors to provide the same capabilities as previous-generation …


Average Speech Directivity, Samuel D. Bellows, Claire M. Pincock, Jennifer K. Whiting, Timothy W. Leishman 2019 Brigham Young University

Average Speech Directivity, Samuel D. Bellows, Claire M. Pincock, Jennifer K. Whiting, Timothy W. Leishman

Directivity

Speech directivity describes the angular dependence of acoustic radiation from a talker’s mouth and nostrils and diffraction about his or her body and chair (if seated). It is an essential physical aspect of communication affecting sounds and signals in acoustical environments, audio, and telecommunication systems. Because high-resolution, spherically comprehensive measurements of live, phonetically balanced speech have been unavailable in the past, the authors have undertaken research to produce and share such data for simulations of acoustical environments, optimizations of microphone placements, speech studies, and other applications. The measurements included three male and three female talkers who repeated phonetically balanced passages …


Analytical Approach To Investigation Of Free Vibration Of Thin Rectangular Plate Immersed In Fluid, Resting On Winkler And Pasternak Foundations, Obanishola Sadiq, Gbeminiyi Sobamowo, Saheed Salawu 2019 University of Lagos

Analytical Approach To Investigation Of Free Vibration Of Thin Rectangular Plate Immersed In Fluid, Resting On Winkler And Pasternak Foundations, Obanishola Sadiq, Gbeminiyi Sobamowo, Saheed Salawu

Karbala International Journal of Modern Science

Dynamic behaviour of free vibration of rectangular plate is investigated. This study considered an analytical approach to investigation of free vibration of thin rectangular plate immersed in fluid, resting on Winkler and Pasternak foundations.The governing nonlinear partial differential equation is analyzed using two-dimensional differential transform method. The accuracy of the analytical solutions obtained is verified with existing results in literature and confirmed in excellent agreement. Thereafter, the analytical solutions are used for investigation of effect of elastic foundation, fluid and aspect ratio on vibrating plate.From the result, it is observed that, increase elastic foundation parameters increases natural frequency, increase aspect …


Data Multiplexing In Vector Acoustic Communication: System Design And Experiments, Erjian Zhang 2019 New Jersey Institute of Technology

Data Multiplexing In Vector Acoustic Communication: System Design And Experiments, Erjian Zhang

Dissertations

Acoustic particle velocity channels, which are vector components of the acoustic field, have been recently explored to achieve communication purposes underwater. Vector sensors and transducers that can utilize acoustic particle velocity channels have compact multichannel designs, which are perfect for compact size underwater platforms. In this dissertation, an underwater acoustic multiple-input multiple-output (MIMO) communication system featuring orthogonal frequency division multiplexing (OFDM) and frequency shift keying (FSK) modulation is discussed. By transmitting multiple independent data streams simultaneously over several channels within the same bandwidth, the proposed MIMO system increases the transmission rate. A variety of components of the system such as …


An Analysis Of Perceptual Masking Between Stems In Manually-Mixed Multitrack Audio Using A Cross-Analytic Loudness Model, Brian H. Cofer 2019 Belmont University

An Analysis Of Perceptual Masking Between Stems In Manually-Mixed Multitrack Audio Using A Cross-Analytic Loudness Model, Brian H. Cofer

Student Theses

In music production, there are many tools available to an audio engineer throughout the mixing process to bring a song to completion. Among the most common are level balancing, equalization (EQ), and compression. However, these tools still require the subjective judgments of human engineers to create the desired listening experience. While automated mixing algorithms have been increasingly studied, they have yet to match the skills of even an amateur mixing engineer, in major part, because the subjective mixing decisions of an engineer are difficult to replicate by automated systems. The following research was developed with the primary goal of objectively …


Design Optimization, Analysis, And Control Of Walking Robots, Wankun Sirichotiyakul 2019 Boise State University

Design Optimization, Analysis, And Control Of Walking Robots, Wankun Sirichotiyakul

Boise State University Theses and Dissertations

Passive dynamic walking refers to the dynamical behavior of mechanical devices that are able to naturally walk down a shallow slope in a stable manner, without using actuation or sensing of any kind. Such devices can attain motions that are remarkably human-like by purely exploiting their natural dynamics. This suggests that passive dynamic walking machines can be used to model and study human locomotion; however, there are two major limitations: they can be difficult to design, and they cannot walk on level ground or uphill without some kind of actuation.

This thesis presents a mechanism design optimization framework that allows …


Parameter Estimation And Dynamic State Observer Design For Vapor Compression Systems, Travis D. Pruitt 2019 Boise State University

Parameter Estimation And Dynamic State Observer Design For Vapor Compression Systems, Travis D. Pruitt

Boise State University Theses and Dissertations

Between cooling our house, our workplace, and keeping our food cold both in home and commercially (among other uses), the vapor compression cycle (VCC) is a common method for removing heat from various environments and it accounts for a significant amount of the energy used throughout the world. Therefore, with an ever-growing demand for more efficient processes and reduced energy consumption, improving the ability to accurately model, predict the performance of, and control VCC systems is beneficial to society as whole.

While there is much information available regarding the performance for some of the components found in VCC systems, much …


System Integration Of C-Arm Robotic Prototype Using Motion Capture Guidance For Accurate Repositioning, Alireza Yazdanshenas 2019 University of Texas at Tyler

System Integration Of C-Arm Robotic Prototype Using Motion Capture Guidance For Accurate Repositioning, Alireza Yazdanshenas

Mechanical Engineering Theses

One of the important surgical tools in spinal surgery is the C-Arm X-ray System. The C-Arm is a large “C” shaped and manually maneuvered arm that provides surgeons and X-ray technicians the ability to take quick quality X-rays during surgery. Because of its five degrees of freedom, the C-Arm can be manually maneuvered around the patient to provide many angles and perspectives, ensuring surgical success.

This system works fine for most surgical procedures but falls short when the C-Arm must be moved out of the way for complicated surgical procedures.

The aim of this thesis is to develop an accurate …


Investigation Of Fundamental Principles Of Rigid Body Impact Mechanics, Khalid Alluhydan 2019 Southern Methodist University

Investigation Of Fundamental Principles Of Rigid Body Impact Mechanics, Khalid Alluhydan

Mechanical Engineering Research Theses and Dissertations

In impact mechanics, the collision between two or more bodies is a common, yet a very challenging problem. Producing analytical solutions that can predict the post-collision motion of the colliding bodies require consistent modeling of the dynamics of the colliding bodies. This dissertation presents a new method for solving the two and multibody impact problems that can be used to predict the post-collision motion of the colliding bodies. Also, we solve the rigid body collision problem of planar kinematic chains with multiple contacts with external surfaces.

In the first part of this dissertation, we study planar collisions of Balls and …


Electronic Cvt - Controls, Alec William Hardy, Jessalyn Leora Ann Bernick, Nicholas Esteban Capdevila, Tristan Charles Perry 2019 California Polytechnic State University, San Luis Obispo

Electronic Cvt - Controls, Alec William Hardy, Jessalyn Leora Ann Bernick, Nicholas Esteban Capdevila, Tristan Charles Perry

Mechanical Engineering

The following document outlines the design process, manufacturing, and testing of the control system for an electronically controlled continuously variable transmission (ECVT). This control system was integrated into the custom designed and manufactured mechanical transmission system created in parallel by another senior project group. The transmission was designed for use in the Cal Poly Baja SAE vehicle. Through researching customer needs, competition requirements, previous and alternate CVT designs, and vehicle characteristics, we were able to determine the requirements and specifications for our unique system. Input, output, speed, and durability requirements guided our hardware selection. The primary components which comprised our …


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