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Reinventing The Wheel, Esther K. Unti, Ahmed Z. Shorab, Patrick B. Kragen, Adam M. Menashe 2018 California Polytechnic State University, San Luis Obispo

Reinventing The Wheel, Esther K. Unti, Ahmed Z. Shorab, Patrick B. Kragen, Adam M. Menashe

Mechanical Engineering

Reinventing the Wheel selected tires and designed wheels for the 2018 Cal Poly, San Luis Obispo Formula SAE combustion vehicle. Available tire options were evaluated for steady-state and transient performance as well as vehicle integration. A single-piece composite wheel with hollow spokes was designed to meet stiffness, strength, and tolerance requirements. A detailed study of wheel loading and geometric structural efficiency was performed. Finite element analysis was used to iterate the geometry and laminate. A two-piece male mold was designed and machined to manufacture the wheel. Removable silicone inserts were used to create the hollow spokes.


Measuring Characteristic Shrinkage Variability Due To Metal Loading Effects In Low Temperature Co-Fired Ceramic Using Image Processing, John Ezekiel Zumbro 2018 University of Arkansas, Fayetteville

Measuring Characteristic Shrinkage Variability Due To Metal Loading Effects In Low Temperature Co-Fired Ceramic Using Image Processing, John Ezekiel Zumbro

Theses and Dissertations

Low temperature co-fired ceramic (LTCC) has many benefits when it comes to electronic packaging due to the low dielectric loss, reliability in extreme environments, and high breakdown voltage. Though the ceramic has a lot of benefits it is not widely used due to the high cost and complexities associated with manufacturing. One of these issues with manufacturing is compensating for the shrinkage of the ceramic, this is accomplished by using an expansion factor, creating the “green” or manufactured design. This expansion factor is approximated through knowledge of the ceramic factors such as the metal loading, layers of ceramic tape, firing ...


Comparative Study Of Power Semiconductor Devices In A Multilevel Cascaded H-Bridge Inverter, Kenneth Mordi 2018 University of Arkansas, Fayetteville

Comparative Study Of Power Semiconductor Devices In A Multilevel Cascaded H-Bridge Inverter, Kenneth Mordi

Theses and Dissertations

This thesis compares the performance of a nine-level transformerless cascaded H-bridge (CHB) inverter with integrated battery energy storage system (BESS) using SiC power MOSFETs and Si IGBTs. Two crucial performance drivers for inverter applications are power loss and efficiency. Both of these are investigated in this thesis. Power devices with similar voltage and current ratings are used in the same inverter topology, and the performance of each device is analyzed with respect to switching frequency and operating temperature. The loss measurements and characteristics within the inverter are discussed. The Saber® simulation software was used for the comparisons. The power MOSFET ...


Simplified Approach For Structural Evaluation Of Flexible Pavements At The Network Level, Mena Souliman, Stefan Romanoschi, Samer Dessouky 2018 University of Texas at Tyler

Simplified Approach For Structural Evaluation Of Flexible Pavements At The Network Level, Mena Souliman, Stefan Romanoschi, Samer Dessouky

Publications

Currently, there are few available simple procedures to identify structurally weak pavement sections utilizing Falling Weight Deflectometer (FWD) data at the network level (e.g., city, state or province). A simple method is required to determine the structural condition of pavement sections that can be directly implemented and automated in current pavement databases. The objective of this research study is to develop a simple analysis method to determine the structural condition of pavement sections utilizing the currently available non-destructive testing (NDT) deflection measurement devices at the network level that can be directly implemented and automated in the database of a ...


Development And Characterization Of Nano Nickel-Based Conductive Inks For Flexographic Printing Of Electronics And New Interpretations Of Surface Energies Of Solids, Bilge N. Altay 2018 Western Michigan University

Development And Characterization Of Nano Nickel-Based Conductive Inks For Flexographic Printing Of Electronics And New Interpretations Of Surface Energies Of Solids, Bilge N. Altay

Bilge Nazli Altay

Traditional printing technologies and conductive/functional inks have been integrated to print electronic devices and circuits on really think, lightweight and flexible materials in a time and cost-effective manner. Printing is an additive manufacturing technology, which selectively deposits materials only where needed to produce a wide range of devices including sensors, smart packaging, solar panels, batteries, light sources and wearable electronics. Therefore, it greatly reduces the number of required steps for manufacturing as well as the amount of waste generated relative to conventional electronic manufacturing. However, the process requirements and ink formulations to print electronics differ from graphic printing; therefore ...


Impact Of Substrate And Process On The Electrical Performance Of Screen-Printed Nickel Electrodes: Fundamental Mechanism Of Ink Film Roughness, Bilge N. Altay, Jerome Jourdan, Vikram S. Turkani, Hervé Dietsch, Dinesh Maddipatla, Alexandra Pekarovicova, Paul D. Fleming, Massood Atashbar 2018 Western Michigan University

Impact Of Substrate And Process On The Electrical Performance Of Screen-Printed Nickel Electrodes: Fundamental Mechanism Of Ink Film Roughness, Bilge N. Altay, Jerome Jourdan, Vikram S. Turkani, Hervé Dietsch, Dinesh Maddipatla, Alexandra Pekarovicova, Paul D. Fleming, Massood Atashbar

Bilge Nazli Altay

In recent years, traditional printing methods have been integrated to print flexible electronic devices and circuits. Since process requirements for electronics diff er from those for graphic printing, the fundamentals require rediscovery mainly to optimize manufacturing techniques and to find cost reduction methods without compromising functional performance. In addition, alternative inks need to be formulated to increase the variety of functional inks and to pioneer new product developments. In this report, we investigate a thermoplastic-based nickel ink prototype to print electrodes using a screen-printing process. Process fundamentals are explored, and cost reduction methods are addressed by studying ...


Metal Segregation During The Solidification Of Titanium-Aluminum Alloys For 3d Printing Applications, Jwala Parajuli 2018 Louisiana Tech University

Metal Segregation During The Solidification Of Titanium-Aluminum Alloys For 3d Printing Applications, Jwala Parajuli

Master's Theses

Titanium-Aluminum alloys are one of the widely used alloys in multiple engineering applications. They are highly preferred in Selective Laser Melting (SLM) processes due to their low density, high melting temperature, and good strength. Segregation occurs during the solidification of most alloys and produces a non-uniform distribution of atoms. In SLM, segregation may depict the type of adhesion between the two deposited interfacial layers and the strength between the interphase between an already solidified layer and a new one, and overall, the quality of the printed part. In order to avoid segregation, the understanding of the segregation behavior at atomistic ...


Effective Magnetic And Electric Response Of Composite Materials, Mona Hassan Alsaleh 2018 Louisiana Tech University

Effective Magnetic And Electric Response Of Composite Materials, Mona Hassan Alsaleh

Doctoral Dissertations

Metamaterials (MMs) are nanocomposite materials consisting of metal-dielectric resonators much smaller in size than the wavelength of the incident light. Common examples of metamaterials are based on split ring resonators (SRRs), parallel wires or strips and fishnet structures. These types of materials are designed and fabricated in order to provide unique optical responses to the incident electromagnetic radiation that are not available in naturally existing materials. The MMs can exhibit unusual properties such as strong magnetism at terahertz (THz) and optical frequencies. Additionally, negative index materials (NIMs) can provide negative index of refraction which can be used in many applications ...


Mechanical Characterization Of Expanded Polystyrene Spheres Embed Sandwich Composites For Packaging Applications, Maheswaran R, Arockia Reemas S 2018 Mepco Schlenk Engineering College

Mechanical Characterization Of Expanded Polystyrene Spheres Embed Sandwich Composites For Packaging Applications, Maheswaran R, Arockia Reemas S

Journal of Applied Packaging Research

This paper addresses on study of development of new packaging material comprising Expanded Polystyrene Spheres (EPS) embedded epoxy polymer based sandwich composites with aluminium skin. The density of the packing material is controlled by varying the volume of embedded spheres. In this study, the Flexural and Compression performance of Expanded Polystyrene Spheres (EPS) embedded polymer based sandwich composites with aluminium skin are investigated. The EPS volume percent in the core is 25% with epoxy matrix which makes the the density less than 1 g/cm3 for the composite. The fabricated Sandwich Composite are very light weight, the density is less ...


Creating A Computational Tool To Simulate Vibration Control For Piezoelectric Devices, Ahmet Ozkan Ozer, Emma J. Moore 2018 Western Kentucky University

Creating A Computational Tool To Simulate Vibration Control For Piezoelectric Devices, Ahmet Ozkan Ozer, Emma J. Moore

Posters-at-the-Capitol

Piezoelectric materials have the unique ability to convert electrical energy to mechanical vibrations and vice versa. This project takes a stab to develop a reliable computational tool to simulate the vibration control of a novel “partial differential equation” model for a piezoelectric device, which is designed by integrating electric conducting piezoelectric layers constraining a viscoelastic layer to provide an active and lightweight intelligent structure. Controlling unwanted vibrations on piezoelectric devices (or harvesting energy from ambient vibrations) through piezoelectric layers has been the major focus in cutting-edge engineering applications such as ultrasonic welders and inchworms. The corresponding mathematical models for piezoelectric ...


Electrically-Conductive Asphalt Mastic: Temperature Dependence And Heating Efficiency, Ali Arabzadeh, Halil Ceylan, Sunghwan Kim, Alireza Sassani, Kasthurirangan Gopalakrishnan, Mani Mina 2018 Iowa State University

Electrically-Conductive Asphalt Mastic: Temperature Dependence And Heating Efficiency, Ali Arabzadeh, Halil Ceylan, Sunghwan Kim, Alireza Sassani, Kasthurirangan Gopalakrishnan, Mani Mina

Civil, Construction and Environmental Engineering Publications

Asphalt mastic, a pitch-matrix composite, consists of bitumen and mineral fillers (very fine aggregates), that fills the voids created by coarser aggregates in asphalt concrete. In this study, asphalt mastic was modified with carbon fiber (CF) and graphite powder (GP) to produce single-phase (containing only CF) and two-phase (containing both CF and GP) electrically-conductive asphalt mastic (ECAM) for anti-icing and deicing applications. Volume resistivities of ECAMs were measured at two different temperatures and the influence of temperature on electrical conductivity was evaluated, revealing that reduction in temperature enhances the ECAM's electrical conductivity. After analyzing the volume resistivity data for ...


Global Packaging Trends, Bekir Keskin, Bilge N. Altay, Merve Akyol, Guven Meral, Olgun Uyar, Paul D. Fleming 2018 Haci Bayram Veli University

Global Packaging Trends, Bekir Keskin, Bilge N. Altay, Merve Akyol, Guven Meral, Olgun Uyar, Paul D. Fleming

Bilge Nazli Altay

The packaging sector is one of the massive traditional fields in the printing industry. The rapid developments in technology and environmental regulations have been affecting the expectations from packaging. User demands and the concerns to protect the environment are the two main factors that now demanding change in material properties. The choice used to depend on the physical and chemical requirements of the products, although today’s global mind set on the concepts such as biodegradability, recyclability, reusability, sustainability and carbon footprint reduction are becoming the reason to tailor packaging properties. In general, the choices have been switching from petroleum ...


Multidimensional Optimal Droop Control For Dc Microgrids In Military Applications, Kaitlyn J. Bunker, Michael D. Cook, Wayne Weaver, Gordon Parker 2018 Michigan Technological University

Multidimensional Optimal Droop Control For Dc Microgrids In Military Applications, Kaitlyn J. Bunker, Michael D. Cook, Wayne Weaver, Gordon Parker

Michigan Tech Publications

Reliability is a key consideration when microgrid technology is implemented in military applications. Droop control provides a simple option without requiring communication between microgrid components, increasing the control system reliability. However, traditional droop control does not allow the microgrid to utilize much of the power available from a solar resource. This paper applies an optimal multidimensional droop control strategy for a solar resource connected in a microgrid at a military patrol base. Simulation and hardware-in-the-loop experiments of a sample microgrid show that much more power from the solar resource can be utilized, while maintaining the system’s bus voltage around ...


Photocatalytic Activity: Experimental Features To Report In Heterogeneous Photocatalysis, Md. Ariful Hoque, Marcelo I. Guzman 2018 University of Kentucky

Photocatalytic Activity: Experimental Features To Report In Heterogeneous Photocatalysis, Md. Ariful Hoque, Marcelo I. Guzman

Chemistry Faculty Publications

Heterogeneous photocatalysis is a prominent area of research with major applications in solar energy conversion, air pollution mitigation, and removal of contaminants from water. A large number of scientific papers related to the photocatalysis field and its environmental applications are published in different journals specializing in materials and nanomaterials. However, many problems exist in the conception of papers by authors unfamiliar with standard characterization methods of photocatalysts as well as with the procedures needed to determine photocatalytic activities based on the determination of “apparent quantum efficiencies” within a wavelength interval or “apparent quantum yields” in the case of using monochromatic ...


Hemodynamics And Pathology Of An Enlarging Abdominal Aortic Aneurysm Model In Rabbits, Hongmei Chen, Yonghua Bi, Siyeong Yu, Linxia Gu, Xiaoyan Zhu, Xinwei Han 2018 Zhengzhou University & Zhengzhou Central Hospital Affiliated to Zhengzhou University

Hemodynamics And Pathology Of An Enlarging Abdominal Aortic Aneurysm Model In Rabbits, Hongmei Chen, Yonghua Bi, Siyeong Yu, Linxia Gu, Xiaoyan Zhu, Xinwei Han

Mechanical & Materials Engineering Faculty Publications

Hemodynamics may play an essential role in the initiation and progression of abdominal aortic aneurysm (AAA). We aimed to study the mechanism of self-healing process by the changes of hemodynamics and pathology in an enlarging AAA in rabbits. Seventy-two rabbits were randomly divided into three groups. Rabbits underwent extrinsic coarctation and received a 10-minute elastase incubation in Group A and Group B. Absorbable suture used in Group A was terminated by balloon dilation at week 4. Diameter was measured after 1, 3, 5, and 15 weeks, computational fluid dynamics analysis was performed at week 3 and week 15. Rabbits were ...


Techniques To Stimulate And Interrogate Cell–Cell Adhesion Mechanics, Ruiguo Yang, Joshua A. Broussard, Kathleen J. Green, Horacio D. Espinosa 2018 University of Nebraska-Lincoln

Techniques To Stimulate And Interrogate Cell–Cell Adhesion Mechanics, Ruiguo Yang, Joshua A. Broussard, Kathleen J. Green, Horacio D. Espinosa

Mechanical & Materials Engineering Faculty Publications

Cell–cell adhesions maintain the mechanical integrity of multicellular tissues and have recently been found to act as mechanotransducers, translating mechanical cues into biochemical signals. Mechanotransduction studies have primarily focused on focal adhesions, sites of cell-substrate attachment. These studies leverage technical advances in devices and systems interfacing with living cells through cell–extracellular matrix adhesions. As reports of aberrant signal transduction originating from mutations in cell–cell adhesion molecules are being increasingly associated with disease states, growing attention is being paid to this intercellular signaling hub. Along with this renewed focus, new requirements arise for the interrogation and stimulation of ...


The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco 2018 University of Central Florida

The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco

Buenaventura "Ven" Basco

No abstract provided.


Solid-State Processing Approach To Enhance The Mechanical Properties Of Polypropylene, Sharon Lau, Srikanthan Ramesh, Iris V. Rivero, LaShanda Korley 2018 Iowa State University

Solid-State Processing Approach To Enhance The Mechanical Properties Of Polypropylene, Sharon Lau, Srikanthan Ramesh, Iris V. Rivero, Lashanda Korley

Sharon Lau

Agenda: Background; Research Problem; Methodology; Results and Discussion; Conclusions.


Method To Provide Meta-Stable Operation Of Dc Microgrid Comprising A Pulsed Load, David G. Wilson, Wayne Weaver, Rush D. Robinett III, Ronald Matthews, Steven F. Glover 2018 Michigan Technological University

Method To Provide Meta-Stable Operation Of Dc Microgrid Comprising A Pulsed Load, David G. Wilson, Wayne Weaver, Rush D. Robinett Iii, Ronald Matthews, Steven F. Glover

Michigan Tech Patents

A Hamiltonian surface shaping power flow control (HSSPFC) method is used to analyze the meta-stability and adjust pulsed power loads on a DC electric power distribution network. Pulsed power loads are nonlinear, time-variant systems that cause nonlinear limit-cycles. During the on periods of a pulsed load, the system can be in an unstable state and is damped back to stability during the off state of the load. Therefore, over the entire period of the pulse the system may only be assessed as meta-stable. As shown through simulation, HIL and hardware results, the HSSPFC method is more accurate than the other ...


Current-Driven Production Of Vortex-Antivortex Pairs In Planar Josephson Junction Arrays And Phase Cracks In Long-Range Order, Francisco Estellés-Duart, Miguel Ortuño, Andrés M. Somoza, Valerii M. Vinokur, Alex Gurevich 2018 Old Dominion University

Current-Driven Production Of Vortex-Antivortex Pairs In Planar Josephson Junction Arrays And Phase Cracks In Long-Range Order, Francisco Estellés-Duart, Miguel Ortuño, Andrés M. Somoza, Valerii M. Vinokur, Alex Gurevich

Physics Faculty Publications

Proliferation of topological defects like vortices and dislocations plays a key role in the physics of systems with long-range order, particularly, superconductivity and superfluidity in thin films, plasticity of solids, and melting of atomic monolayers. Topological defects are characterized by their topological charge reflecting fundamental symmetries and conservation laws of the system. Conservation of topological charge manifests itself in extreme stability of static topological defects because destruction of a single defect requires overcoming a huge energy barrier proportional to the system size. However, the stability of driven topological defects remains largely unexplored. Here we address this issue and investigate numerically ...


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