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Full-Text Articles in Electronic Devices and Semiconductor Manufacturing

Synthesis Of Graphene Using Plasma Etching And Atmospheric Pressure Annealing: Process And Sensor Development, Andrew Robert Graves Jan 2020

Synthesis Of Graphene Using Plasma Etching And Atmospheric Pressure Annealing: Process And Sensor Development, Andrew Robert Graves

Graduate Theses, Dissertations, and Problem Reports

Having been theorized in 1947, it was not until 2004 that graphene was first isolated. In the years since its isolation, graphene has been the subject of intense, world-wide study due to its incredibly diverse array of useful properties. Even though many billions of dollars have been spent on its development, graphene has yet to break out of the laboratory and penetrate mainstream industrial applications markets. This is because graphene faces a ‘grand challenge.’ Simply put, there is currently no method of manufacturing high-quality graphene on the industrial scale. This grand challenge looms particularly large for electronic applications where the …


Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin Jun 2019

Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin

Honors Theses

Structural health monitoring has the potential to allow composite structures to be more reliable and safer, then by using more traditional damage assessment techniques. Structural health monitoring (SHM) utilizes individual sensor units that are placed throughout the load bearing sections of a structure and gather data that is used for stress analysis and damage detection. Statistical time based algorithms are used to analyze collected data and determine both damage size and probable location from within the structure. While traditional calculations and life span analysis can be done for structures made of isotropic materials such as steel or other metals, composites …


Analyses Of Densely Crosslinked Phenolic Systems Using Low Field Nmr, Jigneshkumar Patel Nov 2017

Analyses Of Densely Crosslinked Phenolic Systems Using Low Field Nmr, Jigneshkumar Patel

Doctoral Dissertations

A uniform dispersion of reactants is necessary to achieve a complete reaction involving multi-components, especially for the crosslinking of rigid high-performance materials. In these reactions, miscibility is crucial for curing efficiency. This miscibility is typically enhanced by adding a third component, a plasticizer. For the reaction of the highly crystalline crosslinking agent hexamethylenetetramine (HMTA) with a strongly hydrogen-bonded phenol formaldehyde resin, furfural has been traditionally used as the plasticizer. However, the reason for its effectiveness is not clear. In this doctoral thesis work, miscibility and crosslinking efficiency of plasticizers in phenolic curing reactions are studied by thermal analysis and spectroscopic …


Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic Sep 2017

Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic

Journal of Aviation Technology and Engineering

A proposed novel DC-Link VSCF AC-DC-AC electrical power system converter for Embraer 190/195 transport category airplane is presented. The proposed converter could replace the existing conventional system based on the CSCF IDGs. Several contemporary production airplanes already have VSCF as a major or backup source of electrical power. Problems existed with the older VSCF systems in the past; however, the switched power electronics and digital controllers have matured and can be now, in our opinion, safely integrated and replace existing constant-speed hydraulic transmissions powering CSCF AC generators. IGBT power transistors for medium-level power conversion and relatively fast efficient switching are …


An Exact Analysis For Four-Order Acousto-Optic Bragg Diffraction Which Incorporates Both Incident Light Angle And Sound Frequency Dependencies, Adeyinka Sunday Ademola May 2017

An Exact Analysis For Four-Order Acousto-Optic Bragg Diffraction Which Incorporates Both Incident Light Angle And Sound Frequency Dependencies, Adeyinka Sunday Ademola

Electrical Engineering Theses

This thesis extends the prior work which produced an exact solution to the four-order acousto-optic (AO) Bragg cell with assumed fixed center frequency and with exact Bragg angle incident light. The extension predicts the model that incorporates the dependencies of both the input angle of light and the sound frequency. Specifically, a generalized 4th order linear differential equation (DE), is developed from a simultaneous analysis of four coupled AO system of DEs. Through standard methods, the characteristic roots, which requires solving a quartic equation, is produced. Subsequently, a derived system of homogeneous solutions, which absorbs the roots obtained using …


Control Of A Fuel Cell Based Autonomous Electric Power System For An Aerospace Vehicle, Roshini S. Ashok Oct 2014

Control Of A Fuel Cell Based Autonomous Electric Power System For An Aerospace Vehicle, Roshini S. Ashok

Von Braun Symposium Student Posters

No abstract provided.


Characterization And Testing Of A 5.8 Kv Sic Pin Diode For Electric Space Propulsion Applications, Alexandra Toftul Aug 2014

Characterization And Testing Of A 5.8 Kv Sic Pin Diode For Electric Space Propulsion Applications, Alexandra Toftul

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Inductive Pulsed Plasma Thrusters (IPPTs) are a type of in-space propulsion that has multiple advantages over conventional chemical propulsion for long-duration, deep space missions. Existing IPPT prototypes utilize spark gap switches, however these are subject to corrosion problems that make them unreliable for long-term use. Recent advances in solid state switching technology have opened up a variety of switching options that could provide greater reliability, controllability, and increased energy efficiency. Taking advantage of this, a novel thruster drive circuit topology containing a high-power silicon controlled rectifier (SCR) and series fast recovery diode (FRD) is proposed that is expected to increase …


Materials Selection And Processing Techniques For Small Spacecraft Solar Cell Arrays, Naseem M. Torabi Jan 2013

Materials Selection And Processing Techniques For Small Spacecraft Solar Cell Arrays, Naseem M. Torabi

Theses and Dissertations--Electrical and Computer Engineering

Body mounted germanium substrate solar cell arrays form the faces of many small satellite designs to provide the primary power source on orbit. High efficiency solar cells are made affordable for university satellite programs as triangular devices trimmed from wafer scale solar cells. The smaller cells allow array designs to pack tightly around antenna mounts and payload instruments, giving the board design flexibility. One objective of this work is to investigate the reliability of solar cells attached to FR-4 printed circuit boards. FR-4 circuit boards have significantly higher thermal expansion coefficients and lower thermal conductivities than germanium. This thermal expansion …


Adaptive Control Of A Projectile Fin Using Piezoelectric Elastic Beam, Smitha Mani, Sahjendra N. Singh, Surya Kiran Parimi, Woosoon Yim, Mohamed B. Trabia Aug 2005

Adaptive Control Of A Projectile Fin Using Piezoelectric Elastic Beam, Smitha Mani, Sahjendra N. Singh, Surya Kiran Parimi, Woosoon Yim, Mohamed B. Trabia

Mechanical Engineering Faculty Research

No abstract provided.