An Electromagnetic Energy Harvester For Powering Consumer Electronics,
2012
Clemson University
An Electromagnetic Energy Harvester For Powering Consumer Electronics, Xiyuan Liu
All Theses
This thesis introduces an electromagnetic vibratory energy harvester to power consumer electronics by generating electricity from the strides taken during walking or jogging. The harvester consists of a magnetic pendulum oscillating between two fixed magnets. The pendulum behaves similar to a rotor in a DC generator, while the fixed magnets, which are poled opposite to the pendulum, provide magnetic restoring forces similar to mechanical springs. When attached to a person's arm, the swinging motion subjects the magnetic pendulum to base excitations. Consequently, the pendulum oscillates near a stator which has three poles of wound copper coils. The motion of the …
Vibration And Acoustic Performance Of In-Plane Honeycomb Sandwich Panels,
2012
Clemson University
Vibration And Acoustic Performance Of In-Plane Honeycomb Sandwich Panels, Xiao Gong
All Theses
Sandwich panel structures constructed with cellular honeycomb cores allow for control of acoustic performance due to their ability to optimize effective orthotropic material properties with changes in cell geometry. By modification of topology and geometric parameters of a unit cell, desirable effective properties can be obtained and used to design lightweight structures with reduced vibration and increased sound transmission loss properties. Thus investigating the relation between the geometric configuration of the honeycomb core and vibration and acoustic behavior is important to optimize design of sandwich panels.
In this work, a finite element model is developed in MATLAB to evaluate the …
Effects Of Acoustic Environments On Speech Comprehension By Native-English-Speaking Listeners,
2012
University of Nebraska - Lincoln
Effects Of Acoustic Environments On Speech Comprehension By Native-English-Speaking Listeners, Zhao Peng, Lily M. Wang, Siu Kit Lau
Durham School of Architectural Engineering and Construction: Faculty Publications
This study investigates the effects of acoustic conditions on speech comprehension, rather than speech intelligibility as often reported in existing literature. Sets of 15-minute-long listening comprehension tests were developed based on the format of the Test of English for International Communication (TOEIC). Each test set includes four types of tasks: matching aural phrases to photographs, selecting appropriate responses to aural questions, and answering questions after listening to conversations (between two talkers) and talks (single talker). Within the Nebraska acoustics test chamber, native-English-speaking participants are asked to perform these tests under 15 acoustic conditions, from combinations of three background noise levels …
Changes In In Vivo Knee Contact Forces Through Gait Modification,
2012
University of Dayton
Changes In In Vivo Knee Contact Forces Through Gait Modification, Allison Kinney, Thor F. Besier, Amy Slider, Scott L. Delp, Darryl D. D'Lima, Benjamin J. Fregly
Mechanical and Aerospace Engineering Faculty Publications
Gait modification represents a non-invasive method for reducing knee joint loading in patients with knee osteoarthritis. Previous studies have shown that a variety of gait modifications are effective in reducing the external knee adduction moment. The external knee adduction moment is often used as a surrogate measure of medial compartment force. However, a recent study showed that reductions in the external knee adduction moment do not guarantee reductions in medial compartment loads. Therefore, direct measurement of changes in knee contact force is important for determining the effectiveness of gait modifications. A previous study found that medial thrust gait and walking …
Gpu-Accelerated Modeling Of Microscale Atmospheric Flows Over Complex Terrain,
2012
Boise State University
Gpu-Accelerated Modeling Of Microscale Atmospheric Flows Over Complex Terrain, Anthony Rey Deleon
Boise State University Theses and Dissertations
With installed wind power capacities steadily on the rise, balancing the loads on electrical grids is challenging due to the intermittency of the wind. Short-term wind power forecasting can be a valuable tool for better informing grid operators on the available wind power. Current short-term wind forecasting techniques typically adopt mesoscale weather forecasting models with spatial resolutions on the order of a kilometer. On relatively flat terrain, use of mesoscale models may prove effective, but application to complex terrain induces large forecasting errors. To address this issue, a baseline incompressible flow solver for GPU (graphics processing unit) clusters is extended …
A Case Study For Financial Feasibility Of Automated Costing Support In A Small Machine Shop,
2012
University of Texas-Pan American
A Case Study For Financial Feasibility Of Automated Costing Support In A Small Machine Shop, Benito A. Gonzalez
Theses and Dissertations - UTB/UTPA
A knowledge-based cost estimating expert system is chosen by a Mexican machine shop. Differences between the traditional experience-based system employed and the automated system are studied. Data is gathered to analyze time effectiveness, accuracy and payback of the software. Data from seventy part models is recorded to study the time experiment, and data from fifty part models is used to study the accuracy and consistency. Data is analyzed by calculating mean, standard deviation, and test of hypothesis. The results indicate that the software is faster than the traditional quoting system; however, the payback point is high. Also, results show the …
Load Sensor In An Elastomer Suspension Element,
2012
University of Texas-Pan American
Load Sensor In An Elastomer Suspension Element, Jazmin Ley
Theses and Dissertations - UTB/UTPA
Knowledge of the loading applied to railcar suspension elements is necessary for improved rail safety, efficiency, and for monitoring bearing health. An economical, reliable system for keeping track of both dynamic and static loads on a rail car bearing offers potential for many improvements in rail service. The difficulties of implementing such a system are considerable because the sensor must be in the bearing load path and is thus subject to all the stressors of that environment including high impact, high load, high temperature, and corrosion. This thesis describes an attempt to incorporate a load measurement system in a polyurethane …
Absorber Geometry Optimization For A New Wave Energy Converter,
2012
Western Michigan University
Absorber Geometry Optimization For A New Wave Energy Converter, Rachel A. Durren
Masters Theses
Alternative energy technologies are on the forefront of research due to the rising costs of oil and natural gas. One relatively under development source of energy is ocean waves. In order to make the use of ocean waves economically viable, the amount of energy absorbed by wave energy converters (WEC) must be optimized. The research within presents a new conceptual design, "Aqua Fly", for a WEC with emphasis on maximizing the amount of energy absorbed. The energy absorption component of the "Aqua Fly" was isolated and a small scale 2-D study of energy absorption. First, the amount of energy in …
2d Modeling Of Forcespinning™ Nanofiber Formation With Experimental Study And Validation,
2012
University of Texas-Pan American
2d Modeling Of Forcespinning™ Nanofiber Formation With Experimental Study And Validation, Simon Padron
Theses and Dissertations - UTB/UTPA
A newly developed method of producing nanofibers, called Forcespinning™, has proven to be a viable alternative to mass produce nanofibers. Forcespinning™ utilizes centrifugal forces which allow for a host of new materials to be processed into nanofibers while also providing a significant increase in yield and ease of production. To improve and enhance the Forcespinning™ production method, a 2D computational Forcespinning™ fluid dynamics model is developed. Three computer models, namely time-independent and time-dependent inviscid models and a viscous model are obtained and the influences of various parameters on Forcespinning™ fiber formation are obtained. This work also presents a detailed explanation …
Development Of A Ripple Rejection Controller For Dc Commutated Motors,
2012
Utah State University
Development Of A Ripple Rejection Controller For Dc Commutated Motors, Spencer M. Atkin
All Graduate Plan B and other Reports, Spring 1920 to Spring 2023
The requirement of modern systems to be quiet and run smoothly increases production costs. The manufacture and purchase of high quality motors that meet these demands becomes increasingly costly. By using the ever increasing computer power available in micro-controllers, at the same costs, it is possible to use current sensing to develop control adjustments which decrease power ripples caused by the commutators of basic DC commutated motors. These ripples if left unmitigated propagate through to torque ripples which then increase the acoustic noise level present.
Remanufacturing Cleaning Process Evaluation, Comparison And Planning,
2012
University of Texas-Pan American
Remanufacturing Cleaning Process Evaluation, Comparison And Planning, Ozan Yagar
Theses and Dissertations - UTB/UTPA
This thesis aims to combine previous research on remanufacturing cleaning processes and applications into a single decision-making tool, in the form of software, which a remanufacturer can use to find a cleaning system that matches their specific demands. This thesis will provide an in-depth review of each cleaning process, the chemicals used in those processes, and the contamination types for which they were developed. This research also provides evaluation and comparison that assists remanufacturers in designing their cleaning systems. Finally, there will be a description and demonstration of the software. The ultimate goal is to find correct cleaning process to …
Electromagnetic Interference Shielding Effectiveness Of Metallic Thin Films Deposited On High Density Polyethylene And Styrene Butadiene Copolymer Reinforced With Carbon Nanofibers,
2012
University of Texas-Pan American
Electromagnetic Interference Shielding Effectiveness Of Metallic Thin Films Deposited On High Density Polyethylene And Styrene Butadiene Copolymer Reinforced With Carbon Nanofibers, Horus Garcia
Theses and Dissertations - UTB/UTPA
Aluminum, Copper and Silver were deposited by thermal evaporation onto Vapor Grown Carbon Nanofiber (VGCNF) reinforced High Density Polyethylene (HDPE) and Styrene Butadiene Copolymer (SBC) composites. Electromagnetic Interference Shielding Effectiveness (EMI SE) was conducted on the structures to analyze the synergistic effect. Characterization was performed by Scanning Electron Microscopy, X-ray Diffraction, and Atomic Force Microscopy. Adhesion test and surface influence on SE were also performed. It was observed that a single layer metallic thin film on carbon nanofiber (CNF) polymer composite experienced a summation of shielding performance. The EMI SE increased with CNF content increase of 10, 15, and 20 …
Automated Resonant Wireless Power Transfer To Remote Sensors From An Unmanned Aerial Vehicle,
2012
University of Nebraska-Lincoln
Automated Resonant Wireless Power Transfer To Remote Sensors From An Unmanned Aerial Vehicle, Brent Griffin
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Wireless magnetic resonant power transfer is an emerging technology that has many advantages over other wireless power transfer methods due to its safety, lack of interference, and efficiency at medium ranges. In this thesis, we develop a wire- less magnetic resonant power transfer system that enables unmanned aerial vehicles (UAVs) to provide power to, and recharge batteries of, wireless sensors and other electronics far removed from the electric grid. We address the difficulties of implementing and outfitting this system on a UAV with limited payload capabilities and develop a controller that maximizes the received power as the UAV moves into …
Mathematical Model And Experimental Exploration Of The Nanoinjector Lance Array,
2012
Brigham Young University - Provo
Mathematical Model And Experimental Exploration Of The Nanoinjector Lance Array, Nathan C. Toone
Theses and Dissertations
The Nanoinjector Lance Array has been developed to inject foreign material into thousands of cells at once using electrophoresis to attract and repel particles to and from the electrically-charged lances. A mathematical computer model simulating the motion of attracted or repelled proteins informs the design of the nanoinjection lance array system. The model is validated by accurately predicting protein velocity in electrophoresis experiments. A complete analysis of parameters is conducted via simulations and specific research questions regarding the counter electrode of the nanoinjector lance array system are explored using the model. A novel technique for fabricating lance arrays from collapsed …
Design And Testing Of A Biological Microelectromechanical System For The Injection Of Thousands Of Cells Simultaneously,
2012
Brigham Young University - Provo
Design And Testing Of A Biological Microelectromechanical System For The Injection Of Thousands Of Cells Simultaneously, Gregory Herlin Teichert
Theses and Dissertations
The ability to inject DNA and other foreign particles into cells, both germ cells (e.g. to produce transgenic animals) and somatic cells (e.g. for gene therapy), is a powerful tool in genetic research. Nanoinjection is a method of DNA delivery that combines mechanical and electrical methods. It has proven to have higher cell viability than traditional microinjection, resulting in higher integration per injected embryo. The nanoinjection process can be performed on thousands of cells simultaneously using an array of microneedles that is inserted into a monolayer of cells. This thesis describes the needle array design requirements and the fabrication process …
Flame Synthesis Of Iron Oxide Nanowires For Direct Coal Chemical Looping Combustion, And Tungsten Oxide Nanowires For Enhanced Photoelectrochemical Water Splitting,
2012
Florida Institute of Technology
Flame Synthesis Of Iron Oxide Nanowires For Direct Coal Chemical Looping Combustion, And Tungsten Oxide Nanowires For Enhanced Photoelectrochemical Water Splitting, Pratap Rao
Link Foundation Energy Fellowship Reports
The applications of metal oxide NWs are limited because conventional synthesis methods cannot achieve the scalable, rapid, controllable and economical synthesis of high-quality metal oxide NWs. In the present work, two novel methods for the flame synthesis of metal oxide NWs are developed, and the resulting nanowires tested for two promising, emerging energy conversion technologies: 1) Direct Coal Chemical Looping Combustion, and 2) Photoelectrochemical watersplitting. These synthesis methods are rapid, atmospheric, controllable and scalable, result in highly pure and crystalline materials, and could greatly extend the applicability of metal oxide nanowires to largescale energy conversion and storage problems.
The Biomechanical Implications Of An Intrinsic Decompressive Pre-Load On A Posterior Dynamic Stabilization System,
2012
Brigham Young University - Provo
The Biomechanical Implications Of An Intrinsic Decompressive Pre-Load On A Posterior Dynamic Stabilization System, Jeffrey Ellis Harris
Theses and Dissertations
The purpose of this research was to investigate the influence of applying an intrinsic decompressive pre-load to a particular dynamic stabilization device on the biomechanical response of the lumbar spine. The FlexSPAR, which supports this ability, was used as a test case. A finite element model of a full lumbar spine was developed and validated against experimental data, and tested in the primary modes of spinal motion. The model was used to compare five lumbar spine test cases: healthy, degenerate, implanted with a pre-loaded device, implanted with a device without a pre-load, and implanted with rigid fixators. Results indicated that …
Phase-Resolved Characterization Of Conical Turbulent Premixed Flames: An Investigation Of Forced Blowoff Dynamics,
2012
University of Connecticut - Storrs
Phase-Resolved Characterization Of Conical Turbulent Premixed Flames: An Investigation Of Forced Blowoff Dynamics, Sayan Biswas
Master's Theses
Flame dynamics of a bluff body stabilized turbulent premixed flame as it approaches lean blowoff is of interest for practical applications. It is also important to understand the flame behavior under harmonic flow perturbations as it may occur due to acoustically unstable operation of compact combustors. In this study, a harmonically excited conical flame was studied to determine its behavior under strong burning and near blowoff conditions. Chemiluminescence imaging was employed using a Photron high speed camera to characterize the phase resolved flame characteristics for a range of excitation frequencies from 50 to 400 Hz in confined and unconfined geometries. …
Design, Analysis And Testing Of Haptic Feedback System For Laparoscopic Graspers In In Vivo Surgical Robots,
2012
University of Nebraska-Lincoln
Design, Analysis And Testing Of Haptic Feedback System For Laparoscopic Graspers In In Vivo Surgical Robots, Nikhil Salvi
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Laparo-Endoscopic Single Site (LESS) Robotics Surgery is an advanced technology in the field of Minimally Invasive Surgery (MIS). The LESS surgical robots significantly improve the surgeon’s accuracy, dexterity and visualization, and reduce the invasiveness of surgical procedure results in faster recovery time and improved cosmetic results. In a standard robotic endosurgery, the palpation of tissues is performed by laparoscopic graspers located at the end effectors. The master-slave configuration in robotic surgery leads in remote access to the operation site. Therefore, surgeon’s ability to perceive valuable sensory information is severely diminished. Sensory information such as haptics, which is essential for safe …
Characterization Of Ba1-X-YCaXSrYTio3 Perovskites As Pb-Free Dielectric Materials,
2012
University of South Carolina - Columbia
Characterization Of Ba1-X-YCaXSrYTio3 Perovskites As Pb-Free Dielectric Materials, Lingling Zhang, Siwei Wang, Xusheng Wang, Kevin Huang
Faculty Publications
Use of lead-containing piezoelectric components in electrical and electronic devices has been banned on the EU market since July 1st, 2006. Development of lead-free high performance piezoelectric materials to meet the strong market demand is therefore imperative. In this paper, we report a systematic study on the structural, dielectric and ferroelectric properties of one class of lead-free piezoelectric materials, Ba1-x-yCaxSryTiO3 (x = 0-0.4, and y = 0-0.2) ceramics, using techniques such as XRD, SEM, impedance analyzer, and ferroelectric analyzer. It is found that with increasing Sr concentration in Ba …
