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Full-Text Articles in Engineering

Foot Stress And Blood Flow Sensing Under High-Loading During Hip Surgery, Katie Paswaters, Esther Chen, Chris Cardenas, Claire Kingston, Brianna Rodebaugh Jun 2018

Foot Stress And Blood Flow Sensing Under High-Loading During Hip Surgery, Katie Paswaters, Esther Chen, Chris Cardenas, Claire Kingston, Brianna Rodebaugh

Mechanical Engineering

The PolyHIPS team was tasked with integrating sensors into Stryker’s hip arthroscopy boot that monitor blood flow and heel slip during hip surgery. During hip arthroscopy, the femur head is distracted from the acetabulum to create space in the joint for the surgeon to operate. This requires the use of up to 200 lbf. In order to maintain this space, the foot is held tightly in the boot. Complications can result from the foot being held too tightly in the boot during the procedure. The most common complication is neuropraxia, or temporary nerve damage. PolyHIPS proposes a solution that ...


Analysis Of The Properties Of Supercapacitors And Possible Applications For The Technology, Vincent Oliveto Jun 2018

Analysis Of The Properties Of Supercapacitors And Possible Applications For The Technology, Vincent Oliveto

Honors Theses

Supercapacitors have a lot of excellent qualities that would make them a great substitute for batteries when it comes to electrical energy storage systems. Supercapacitors can discharge and charge very rapidly, they have a lifespan in the realm of millions of cycles, and they are much more efficient than batteries. Unfortunately, they cannot hold nearly as much charge as batteries. This paper seeks to further investigate the properties of supercapacitor technology and the best way to exploit these properties with the purpose of integrating them into renewable energy systems. There is currently a lot of research occurring around the world ...


The School Of Engineering And Computer Science Class Of 2018 Mechanical Engineering Academic Celebration, Cedarville University May 2018

The School Of Engineering And Computer Science Class Of 2018 Mechanical Engineering Academic Celebration, Cedarville University

Engineering and Computer Science Academic Celebrations

No abstract provided.


The Rock 2018, School Of Engineering And Computer Science Jan 2018

The Rock 2018, School Of Engineering And Computer Science

The Rock

No abstract provided.


Trochoidal Milling Of Alsicp With Cvd Diamond Coated End Mills, Tony Nguyen Jan 2018

Trochoidal Milling Of Alsicp With Cvd Diamond Coated End Mills, Tony Nguyen

University of the Pacific Theses and Dissertations

Metal matrix composites have seen a rise in demand within the last decade. Aluminum alloy reinforced with silicon carbide particles is a type of particle metal matrix composite that has seen applications in the aerospace, ground transportation, and electronics industry. However, the abrasive SiC particles have made this material difficult to machine through conventional machining strategies. This research will focus on using computer aided manufacturing with trochoidal tool paths to maximize machining productivity and extend the tool life of CVD diamond coated end mills. The focus of this research will be on AlSiCp with a high volume fraction of reinforcement ...


Applications Of Low Field Magnetic Resonance Imaging, Muhammad Waqas Jan 2018

Applications Of Low Field Magnetic Resonance Imaging, Muhammad Waqas

University of the Pacific Theses and Dissertations

Magnetic resonance imaging is a non-invasive imaging modality that is used to produce detailed images of soft tissues within the human body. Typically, MRI scanners used in the clinical setting are high field systems because they have a magnetic field strength greater than 1.5 Tesla. The high magnetic field offers the benefit of high spatial resolution and high SNR. However, low filed systems can also produce high resolution MR images with the added benefit of imaging stiffer samples. In this study, a low field 0.5 T MR system was used to image various samples to demonstrate the capability ...


Rapid Characterization Of Local Shape Memory Properties Through Indentation, Peizhen Li, Haluk E. Karaca, Yang-Tse Cheng Nov 2017

Rapid Characterization Of Local Shape Memory Properties Through Indentation, Peizhen Li, Haluk E. Karaca, Yang-Tse Cheng

Mechanical Engineering Faculty Publications

Shape memory alloys (SMAs) have the ability to show large recoverable shape changes upon temperature, stress or magnetic field cycling. Their shape memory, material and magnetic properties (e.g. transformation temperatures, strain, saturation magnetization and strength) determine their prospects for applications from small-scale microelectromechanical systems to large scale aerospace and biomedical systems. It should be noted that properties of SMAs are highly temperature dependent. Generally, the conventional mechanical characterization methods (e.g, tension, compression, and torsion) are used on bulk samples of SMAs to determine those properties. In this article, it will be shown that indentation technique can be used ...


Innovation Of Driving Gear Train System For Developer Unit Of Lexmark Home Printers, Jay A. Crist, Sarah Gore, Kun Xie, Michael Mixoon Aug 2017

Innovation Of Driving Gear Train System For Developer Unit Of Lexmark Home Printers, Jay A. Crist, Sarah Gore, Kun Xie, Michael Mixoon

University of Tennessee Honors Thesis Projects

No abstract provided.


A Wood-Powered Lawn Mower: Separating The Rules Of Thumb From Engineering Design, William White Jun 2017

A Wood-Powered Lawn Mower: Separating The Rules Of Thumb From Engineering Design, William White

Honors College Capstone Experience/Thesis Projects

Biomass gasification, the thermal process of exracting combustible gasses from organic matter, is an established procedure that has been used for many years to provide fuel in various applications. It is a potential source of renewable fuel and has proven useful as a crisis energy source. This thesis investigates the primary engineering science principles involved in gasifier-engine system design. It arises from and supplements a WKU mechanical engineering senior project. The senior project has developed a wood gasification system designed to power a riding lawn mower. The thesis reiews theory-based design and separates it from informal hit and miss approaches ...


Coupled Phase Transformations And Plastic Flows Under Torsion At High Pressure In Rotational Diamond Anvil Cell: Effect Of Contact Sliding, Biao Feng, Valery I. Levitas Jun 2017

Coupled Phase Transformations And Plastic Flows Under Torsion At High Pressure In Rotational Diamond Anvil Cell: Effect Of Contact Sliding, Biao Feng, Valery I. Levitas

Valery I. Levitas

A three-dimensional large-sliding contact model coupled with strain-induced phase transformations (PTs) and plastic flow in a disk-like sample under torsion at high pressure in rotational diamond anvil cell (RDAC) is formulated and studied. Coulomb and plastic friction are combined and take into account variable parameters due to PT. Results are obtained for weaker, equal-strength, and stronger high pressure phases, and for three values of the kinetic coefficient in a strain-controlled kinetic equation and friction coefficient. All drawbacks typical of problem with cohesion are overcome, including eliminating mesh-dependent shear band and artificial plastic zones. Contact sliding intensifies radial plastic flow, which ...


Influence Of Aluminum Passivation On The Reaction Mechanism: Flame Propagation Studies, Birce Dikici, Steven W. Dean, Michelle L. Pantoya, Valery I. Levitas, R. Jason Jouet Jun 2017

Influence Of Aluminum Passivation On The Reaction Mechanism: Flame Propagation Studies, Birce Dikici, Steven W. Dean, Michelle L. Pantoya, Valery I. Levitas, R. Jason Jouet

Valery I. Levitas

Currently, two main known mechanisms of aluminum (Al) nanoparticle reaction are discussed in the literature, namely those based on diffusion through an oxide shell and melt-dispersion. The two mechanisms lead to opposite predictions in nanoparticle design. The diffusion mechanism suggests that the reduction or complete elimination of the oxide shell will increase Al reactivity, whereas the meltdispersion mechanism suggests an increase in initial oxide thickness up to an optimal value. The goal of this study is to perform critical experiments in a confined flame tube apparatus to compare these two predictions. Specifically, the flame propagation rates of perfluoroalkyl carboxylic acid ...


Cellulose–Hemicellulose And Cellulose–Lignin Interactions During Fast Pyrolysis, Jing Zhang, Yong S. Choi, Chang G. Yoo, Tae H. Kim, Robert C. Brown, Brent H. Shanks Jun 2017

Cellulose–Hemicellulose And Cellulose–Lignin Interactions During Fast Pyrolysis, Jing Zhang, Yong S. Choi, Chang G. Yoo, Tae H. Kim, Robert C. Brown, Brent H. Shanks

Brent H. Shanks

Previously, the primary product distribution resulting from fast pyrolysis of cellulose, hemicellulose, and lignin was quantified. This study extends the analysis to the examinations of interactions between cellulose–hemicellulose and cellulose–lignin, which were determined by comparing the pyrolysis products from their native mixture, physical mixture, and superposition of individual components. Negligible interactions were found for both binary physical mixtures. For the native cellulose–hemicellulose mixture, no significant interaction was identified either. In the case of the native cellulose–lignin mixture, herbaceous biomass exhibited an apparent interaction, represented by diminished yield of levoglucosan and enhanced yield of low molecular weight ...


The School Of Engineering And Computer Science Class Of 2017 Mechanical Engineering Academic Celebration, Cedarville University May 2017

The School Of Engineering And Computer Science Class Of 2017 Mechanical Engineering Academic Celebration, Cedarville University

Engineering and Computer Science Academic Celebrations

No abstract provided.


Virtual Reality Integrated Welder Training, Richard T. Stone, Kristopher Patrick Watts, Peihan Zhong Feb 2017

Virtual Reality Integrated Welder Training, Richard T. Stone, Kristopher Patrick Watts, Peihan Zhong

Richard T. Stone

Training in the welding industry is a critical and often costly endeavor; this study examines the training potential, team learning, material consumption, and cost implications of using integrated virtual reality technology as a major part of welder training. In this study, 22 participants were trained using one of two separate methods (traditional training (TT) and virtual reality integrated training (VRI)). The results demonstrated that students trained using 50% virtual reality had training outcomes that surpassed those of traditionally trained students across four distinctive weld qualifications (2F, 1G, 3F, 3G). In addition, the VRI group demonstrated significantly higher levels of team ...


The Rock 2017, School Of Engineering And Computer Science Jan 2017

The Rock 2017, School Of Engineering And Computer Science

The Rock

No abstract provided.


Adjustable Height Table Chassis, Trevor Watkins Jan 2017

Adjustable Height Table Chassis, Trevor Watkins

All Undergraduate Projects

Having the ability to change a dining table between a sitting and standing position is a niche feature. This feature was created for people that play board games regularly at a table, or for people who require use of a dining table as a standing work area. The mechanism that the table works by is using an acme threaded rod as a lead screw, with two timing belt pullies driving the shafts up and down which cause the raising and lowering of the table. These pullies were machined to incorporate an ACME threaded bolt which was welded into each pully ...


Weather Balloon Payload Box, Shellbie Liberty Jan 2017

Weather Balloon Payload Box, Shellbie Liberty

All Undergraduate Projects

A payload box holding a self-rotating camera was constructed to go on a weather balloon that will document the upcoming solar eclipse on August 21, 2017. A group of physics students, and the paper’s author, are working under Dr. Darci Snowden on the CWU Near Space Observation Team for research dedicated to the eclipse in Oregon. Various projects, including the payload box, are being designed to go up on a high altitude weather balloon. The payload box was designed and constructed to withstand the impact force of falling from 120,000 ft. This was done so the box could ...


Configuration And Electronic Properties Of The Interface Between Lead Iodide Hybrid Perovskite And Self-Assembled Monolayers In Solar Cells, Parin Divya Amlani Jan 2017

Configuration And Electronic Properties Of The Interface Between Lead Iodide Hybrid Perovskite And Self-Assembled Monolayers In Solar Cells, Parin Divya Amlani

Browse all Theses and Dissertations

Hybrid perovskite photovoltaic materials are currently the most promising functional materials for solar cell applications with efficiency reaching to those of more conventional materials such as silicon. Using self-assembled monolayers between photovoltaic materials and electrodes is a method for improving the stability and functionality. Recent experiments have shown that using 4-mercaptobenzoic acid and pentafluorobenzenethiol monolayers bridging lead iodide hybrid perovskite photovoltaic materials and electrodes result in improved stability and efficiency. The details of monolayer assembly, molecular adsorption configuration, and resulting modification of electronic properties are important characteristics related to solar cell performance. These characteristics can be obtained through accurate computer ...


Ab Initio Study Of The Effects Of Humidity On Perovskite Based Hybrid Solar Cell Interfaces, Shantanu Rajendra Rachalwar Jan 2017

Ab Initio Study Of The Effects Of Humidity On Perovskite Based Hybrid Solar Cell Interfaces, Shantanu Rajendra Rachalwar

Browse all Theses and Dissertations

Despite the impressive success of perovskite-based hybrid solar cells, their widespread usage has been limited partially owing to stability issues under working environmental conditions. Among these, the effects of humidity are some of the most significant. Water intercalation generally degrades the material, shortens its useful life, and reduces the efficiency of photovoltaic energy conversion. Understanding the reasons for these effects can be achieved through detailed and accurate atomic-scale analysis. Here, we study water intercalation at the interfaces of perovskite-based hybrid solar cell material and TiO2 electrode. Accurate ab initio computer simulations are used to obtain structural and electronic properties. We ...


Studies Of Ionic Liquid Hybrids: Characteristics And Their Potential Application To Li-Ion Batteries And Li-Ion Capacitors, Mengxin Liu Jan 2017

Studies Of Ionic Liquid Hybrids: Characteristics And Their Potential Application To Li-Ion Batteries And Li-Ion Capacitors, Mengxin Liu

Browse all Theses and Dissertations

Ionic liquids (ILs) have attracted much attention in electrochemical energy storage systems for their advantageous properties over traditional lithium salt/carbonate solvent electrolyte in terms of higher electrochemical potential windows, comparable ionic conductivity, negative vapor pressure and non-flammability. Ionic liquids can be used as the solvent-free electrolyte in electrochemical double layer capacitors (EDLCs) or can act as the important additives to the carbonate electrolyte in lithium ion batteries (LIBs). Recently, lithium ion capacitors (LICs) have emerge as a novel energy storage system to satisfy the demands for higher energy density and higher power density in portable and transportation systems. This ...


Dynamic Modeling Of Thermal Management System With Exergy Based Optimization, Marcus J. Bracey Jan 2017

Dynamic Modeling Of Thermal Management System With Exergy Based Optimization, Marcus J. Bracey

Browse all Theses and Dissertations

System optimization and design of aircraft is required to achieve many of the long term objectives for future aircraft platforms. To address the necessity for system optimization a vehicle-level aircraft model has been developed in a multidisciplinary modeling and simulation environment. Individual subsystem models developed exclusively in MATLAB-SimulinkTM, representing the vehicle dynamics, the propulsion, electrical power, and thermal systems, and their associated controllers, are combined to investigate the energy and thermal management issues of tactical air vehicle platforms. A thermal vehicle level tip-to-tail model allows conceptual design trade studies of various subsystems and can quantify performance gains across the aircraft ...


Design And Validation Of An Electro-Hydraulic Pressure-Control Valve And Closed-Loop Controller, Jerry Boza Dec 2016

Design And Validation Of An Electro-Hydraulic Pressure-Control Valve And Closed-Loop Controller, Jerry Boza

Dissertations

Electro-hydraulic pressure-control valves are used in many applications, such as manufacturing equipment, agricultural machinery, and aircrafts to name a few. They are often used to actuate hydraulic clutches, such as those found in power shift transmissions. A traditional pressure-control valve with open-loop control algorithm is typically used in clutch applications. This scheme often results in inconsistent or undesirable system behavior due to the nature of open-loop control as well as the nonlinear system dynamics and uncertainties.

In this research two new electro-hydraulic pressure-control valves were designed in order to decouple the valve and control port (hydraulic) dynamics. This was achieved ...


Full Virtual Reality Vs. Integrated Virtual Reality Training In Welding, Richard T. Stone, Elease Mclaurin, Peihan Zhong, Kristopher Patrick Watts Jun 2016

Full Virtual Reality Vs. Integrated Virtual Reality Training In Welding, Richard T. Stone, Elease Mclaurin, Peihan Zhong, Kristopher Patrick Watts

Richard T. Stone

This study demonstrates that both fully virtual and virtual reality (VR) integrated into real-world training programs are appropriate for use in the domain of welding training, depending on the level of task difficulty. Performance differences were virtually indistinguishable between participants in the fully virtual and the integrated training group at the low and medium weld difficulty levels. At the highest level of difficulty, it became apparent that the VR system was no longer solely sufficient for training. This study also tracked the usage patterns for the visual aids used in the VR simulator. These optional aids were presented to the ...


The School Of Engineering And Computer Science Class Of 2016 Mechanical Engineering Academic Celebration, Cedarville University May 2016

The School Of Engineering And Computer Science Class Of 2016 Mechanical Engineering Academic Celebration, Cedarville University

Engineering and Computer Science Academic Celebrations

No abstract provided.


Limitations And Tradeoffs In Synchronization Of Large-Scale Networks With Uncertain Links, Amit Diwadkar, Umesh Vaidya Apr 2016

Limitations And Tradeoffs In Synchronization Of Large-Scale Networks With Uncertain Links, Amit Diwadkar, Umesh Vaidya

Electrical and Computer Engineering Publications

The synchronization of nonlinear systems connected over large-scale networks has gained popularity in a variety of applications, such as power grids, sensor networks, and biology. Stochastic uncertainty in the interconnections is a ubiquitous phenomenon observed in these physical and biological networks. We provide a size-independent network sufficient condition for the synchronization of scalar nonlinear systems with stochastic linear interactions over large-scale networks. This sufficient condition, expressed in terms of nonlinear dynamics, the Laplacian eigenvalues of the nominal interconnections, and the variance and location of the stochastic uncertainty, allows us to define a synchronization margin. We provide an analytical characterization of ...


The Role Of Mechanical Design In Mechatronics Education, John Gardner Dec 2015

The Role Of Mechanical Design In Mechatronics Education, John Gardner

John Gardner

A survey of Mechatronics course offerings around the United States shows a rich variety of approaches to this topic.[1] Indeed, it appears that a majority of Mechanical Engineering programs across the county offer some formal offering in this area and it seems clear that the vast majority of Mechatronics courses are offered through Mechanical Engineering departments. With the traditional emphasis on design skill in mechanical engineering, it would seem obvious that mechatronics courses would feature a major design component. Surprisingly, very few existing mechatronics courses (at least those reported in the literature) feature a strong emphasis on mechanical design ...


Implementing A Linear Quadratic Spacecraft Attitude Control System, Daniel Kolosa Dec 2015

Implementing A Linear Quadratic Spacecraft Attitude Control System, Daniel Kolosa

Master's Theses

This thesis implements a linear quadratic attitude control system for a low-thrust spacecraft. The goal is to maintain spacecraft alignment with a time-varying thrust vector needed for trajectory change maneuvers. A linear quadratic attitude control approach is used to maintain spacecraft pointing throughout flight. This attitude control strategy uses the thrust-acceleration input obtained from a linear quadratic optimal trajectory control model that simulates the trajectory of a spacecraft in orbit maneuvers. This attitude model simulates a CubeSat, a small satellite that is equipped with a low-thrust propulsion and attitude control system. An orbit raising and a plane change scenario is ...


Custom Glasses Cases, Nikolas Ivan Klukas May 2015

Custom Glasses Cases, Nikolas Ivan Klukas

Mechanical Engineering and Technology Senior Projects

The modern market is centralized around technological advances that improve and better everyday life. With approximately 150 million Americans that use corrective eye-ware on a daily basis, the need for improved technology in glasses cases is inevitable. Current glasses cases work to either protect the glasses and are big and bulky, or are made smaller to be more easily transported. The concept is to take any pair of glasses and make a custom case for them. The programs being utilized to complete the project are solidworks and excel. The process is started by making a base layout of the glasses ...


Dump Bed Lifting Mechanism, Zachary Pate May 2015

Dump Bed Lifting Mechanism, Zachary Pate

Mechanical Engineering and Technology Senior Projects

The project was motivated by a need to create a device that would cause a small truck or trailer bed to lift up quickly and dump its contents. This would eliminate the need to use manual physical labor, which is both slow and exhausting. Additional design constraints require the stroke and diameter of the cylinder to be 6” x2”. A design was conceived with the intent to incorporate a less costly device onto an existing trailer frame that would lift the bed and dump the load. With this in mind, a scissor lift device would have two basic requirements, first ...


Branch Cutter Adapter For Electric Impact Gun, Cullen Hubbard May 2015

Branch Cutter Adapter For Electric Impact Gun, Cullen Hubbard

Mechanical Engineering and Technology Senior Projects

There are many homeowners that would like to maintain the trees around their homes but cannot do so. The drive of this project was to develop a 0g mechanism which would provide a senior citizen or an individual with limited upper body strength, with the ability to cut through branches that would otherwise pose challenging. The design would allow the end user to cut a branch by simply pulling a trigger. A branch cutting attachment was designed to attach to the front of a DeWALT cordless impact gun. This attachment will convert the rotational torque and motion from the impact ...