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Pre-Breakdown Arcing As A Proxy For Dc Dielectric Breakdown Testing Of Polymeric Insulators, JR Dennison, Allen Andersen 2015 Utah State Univesity

Pre-Breakdown Arcing As A Proxy For Dc Dielectric Breakdown Testing Of Polymeric Insulators, Jr Dennison, Allen Andersen

Presentations

No abstract provided.


Mixed Weibull Distribution Model Of Dc Dielectric Breakdowns With Dual Defect Modes, Allen Andersen, JR Dennison 2015 Utah State University

Mixed Weibull Distribution Model Of Dc Dielectric Breakdowns With Dual Defect Modes, Allen Andersen, Jr Dennison

Presentations

No abstract provided.


Small Satellite Verification And Assessment Test Facility With Space Environments Effects Ground-Testing Capabilities, Eric Stromberg, Crystal Frazier, Lisa Montierth Phillipps, Alex Souvall, JR Dennison, James S. Dyer 2015 Utah State University

Small Satellite Verification And Assessment Test Facility With Space Environments Effects Ground-Testing Capabilities, Eric Stromberg, Crystal Frazier, Lisa Montierth Phillipps, Alex Souvall, Jr Dennison, James S. Dyer

Presentations

The Utah State University Space Dynamics Laboratory (SDL) and Materials Physics Group (MPG) have developed an extensive versatile and cost-effective pre-launch test capability for verification and assessment of small satellites, system components, and spacecraft materials. The facilities can perform environmental testing, component characterization, system level hardware in-the-loop testing, and qualification testing to ensure that each element is functional, reliable, and working per its design. Unique capabilities of SDL’s Nano-Satellite Operation Verification and Assessment (NOVA) test facility include: (i) mass and moment of inertia testing using a high resolution mass measurement table to determine the center of gravity and an ...


Gait Transition Dynamics Are Modulated By Experimental Protocol, Mohammad Abdolvahab, Jason Gordon 2015 University of Connecticut - Storrs

Gait Transition Dynamics Are Modulated By Experimental Protocol, Mohammad Abdolvahab, Jason Gordon

Mohammad Abdolvahab

No abstract provided.


Influence Of Thermal Treatment On Electrical And Physical Properties Of Coated Ceramics, K. Guerch, T. Paulmier, Justin Dekany, JR Dennison, S. Guillemet-Fritsch, P. Lenormand 2015 ONERA

Influence Of Thermal Treatment On Electrical And Physical Properties Of Coated Ceramics, K. Guerch, T. Paulmier, Justin Dekany, Jr Dennison, S. Guillemet-Fritsch, P. Lenormand

Presentations

Technical dielectric materials and ceramics are used in many different high technology industrial areas and especially for spacecraft applications. On satellites, these materials are subjected to extreme conditions due to the space plasma environment. To survive, these ceramic insulators must have exceptional electrical and thermal properties. Boron Nitride (BN) and Aluminum Oxide (Al 2O3) are used in particular because they combine good electrical insulation and high thermal conductivity. However, BN and Al2O3 used in spacecraft interiors are exposed to critical radiation demands, where these insulators are irradiated by electrons with high energies and flux. Charged particles are trapped in the ...


A Solution In Weyl Gravity With Planar Symmetry, James Thomas Wheeler 2015 Utah State University

A Solution In Weyl Gravity With Planar Symmetry, James Thomas Wheeler

James Thomas Wheeler

We solve the Bach equation for Weyl gravity for the case of a static metric with planar symmetry. The solution is not conformal to the solution to the corresponding Einstein equation.


Solid Angle Subtended By A Beam With Rectangular Profile Given The Horizontal & Vertical Beam Angles, Harish Chandra Rajpoot Rajpoot HCR 2015 M.M.M. University of Technology, Gorakhpur-273010 (UP) India

Solid Angle Subtended By A Beam With Rectangular Profile Given The Horizontal & Vertical Beam Angles, Harish Chandra Rajpoot Rajpoot Hcr

Harish Chandra Rajpoot H.C. Rajpoot

All the articles discussed & analysed here are useful for calculating the important parameters such as solid angle subtended by the beam at the point-source, total area intercepted by the beam with a spherical surface & cone angle of equivalent beam with circular section. These formula are very useful for replacing the rectangular profile by circular profile of a beam emitted by a uniform point-source & vice versa without any change in the total radiation energy/luminous flux associated with the original beam (having either rectangular or circular profile). Thus the articles discussed & analysed here are very useful for the analysis of radiation ...


Design, Construction, And Utilization Of Physical Vapor Deposition Systems For Medical Sensor Fabrication, Nicholas Sayre, Erik J. Sánchez, Joe Kowalski 2015 nsayre@pdx.edu

Design, Construction, And Utilization Of Physical Vapor Deposition Systems For Medical Sensor Fabrication, Nicholas Sayre, Erik J. Sánchez, Joe Kowalski

Student Research Symposium

The development of a novel blood glucose sensor is realized through construction of a homemade plasma coating system and utilization of semiconductor manufacturing processes in a small scale cleanroom environment. Photolithography, plasma sputtering, chemical etching and thin film measurement technologies are used in the medical sensor fabrication process. General process flow will be discussed, and system design and the plasma sputtering process will be presented as it is achieved by the system currently under development.


Bicrystallography In Two Dimensions: A Graphical Procedure And Comparison Of Its Results To Experiments, Andrew M. Maas, Peter Moeck 2015 Portland State University

Bicrystallography In Two Dimensions: A Graphical Procedure And Comparison Of Its Results To Experiments, Andrew M. Maas, Peter Moeck

Student Research Symposium

Three dimensional (3D) bicrystallography describes ideal structures of grain boundaries comprehensively at the atomic level as a function of the five macroscopic and two of the four microscopic parameters [1,2]. Free energy minimization of these structures leads to the real structure of these topologically distinct regions within crystals. These minimizations may either reduce the symmetries of ideal bicrystals or leave them intact. Since the symmetries of physical properties need to be compatible (by the Shubnikov-Curie and Curie-Minnigerode-Neumann principles [3]) with the symmetries of the atomic arrangements from which they arise, bicrystallography allows for predictions about which phenomena can occur ...


Investigation Of Asymmetric Impacts On Protective Headgear, Kristina Medero 2015 Western Kentucky University

Investigation Of Asymmetric Impacts On Protective Headgear, Kristina Medero

Honors College Capstone Experience/Thesis Projects

This project explores helmet-to-helmet impacts and their detriments with a unique perspective. The propagation of dangerous waves into the brain can result in a concussion. Considering 60% of NFL players have had at least one concussion (Epstein 2011), it is imperative to understand the materials that construct helmets and observe how these materials behave in regards to impact location while recording wave propagations from the impacts. This study interrogates the effect of asymmetric impacts on gridiron football helmets using the Large Chamber Scanning Electron Microscope (LC-SEM). Utilizing two standard issued football helmets made of polycarbonates, a hard plastic, vibrations from ...


Early Rayleigh-Scatter Lidar Temperature Measurements From The Lower Thermosphere, Leda Sox, Vincent B. Wickwar 2015 Utah State University

Early Rayleigh-Scatter Lidar Temperature Measurements From The Lower Thermosphere, Leda Sox, Vincent B. Wickwar

Leda Sox

Rayleigh-scatter lidar observations were made on many clear nights at the Atmospheric Lidar Observatory (ALO) at Utah State University (USU) from 1993 to 2004 in the altitude range 45–90 km. An upgraded facility, 66 times more sensitive, has been brought on line. It has resulted in temperature measurements with maximum altitudes that extend into new territory—the lower thermosphere. All-night temperature averages have been recorded up to an altitude of 114 km. Temperatures from each month, starting in June 2014, are presented and discussed. They are compared to each other, to the ALO-USU climatology from the original lidar, and ...


Optical Control Of Electron Phase Space In Plasma Accelerators With Incoherently Stacked Laser Pulses, Serge Y. Kalmykov, Xavier Davoine, Remi Lehe, Agustin F. Lifschitz, Bradley A. Shadwick 2015 University of Nebraska-Lincoln

Optical Control Of Electron Phase Space In Plasma Accelerators With Incoherently Stacked Laser Pulses, Serge Y. Kalmykov, Xavier Davoine, Remi Lehe, Agustin F. Lifschitz, Bradley A. Shadwick

Serge Youri Kalmykov

It is demonstrated that synthesizing an ultrahigh-bandwidth, negatively chirped laser pulse by incoherently stacking pulses of different wavelengths makes it possible to optimize the process of electron self-injection in a dense, highly dispersive plasma (n_0 \sim 10^{19} cm^{-3}). Avoiding transformation of the driving pulse into a relativistic optical shock maintains a quasi-monoenergetic electron spectrum through electron dephasing and boosts electron energy far beyond the limits suggested by existing scaling laws. In addition, evolution of the accelerating bucket in a plasma channel is shown to produce a background-free, tunable train of femtosecond-duration, 35 - 100 kA, time-synchronized quasi-monoenergetic electron bunches ...


Coexistence Pressure For A Martensitic Transformation From Theory And Experiment: Revisiting The Bcc-Hcp Transition Of Iron Under Pressure, Nikolai A. Zarkevich, Duane D. Johnson 2015 Ames Laboratory

Coexistence Pressure For A Martensitic Transformation From Theory And Experiment: Revisiting The Bcc-Hcp Transition Of Iron Under Pressure, Nikolai A. Zarkevich, Duane D. Johnson

Ames Laboratory Publications

The coexistence pressure of two phases is a well-defined point at fixed temperature. In experiment, however, due to nonhydrostatic stresses and a stress-dependent potential energy barrier, different measurements yield different ranges of pressure with a hysteresis. Accounting for these effects, we propose an inequality for comparison of the theoretical value to a plurality of measured intervals. We revisit decades of pressure experiments on the bcc↔hcp transformations in iron, which are sensitive to nonhydrostatic conditions and sample size. From electronic-structure calculations, we find a bcc↔hcp coexistence pressure of 8.4GPa. We construct the equation of state for competing phases ...


Magnetoresistance Characteristics In Individual Fe3O4 Single Crystal Nanowire, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna 2015 Boise State University

Magnetoresistance Characteristics In Individual Fe3O4 Single Crystal Nanowire, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna

Physics Faculty Publications and Presentations

We report on the magnetoresistance (MR) and electron transport measurements observed on asingle crystal magnetite nanowire prepared using a hydrothermal synthesis method. High-resolution electron microscopy revealed the single crystal magnetite nanowires with 80–120 nm thickness and up to 8 μm in length. Magnetic measurements showed the typical Verwey transition around 120 K with a 100 Oe room temperature coercivity and 45 emu/g saturationmagnetization, which are comparable to bulk magnetite. Electrical resistance measurements in 5-300 K temperature range were performed by scanning gate voltage and varying appliedmagnetic field. Electrical resistivity of the nanowire was found to be around ...


Heterojunction Metal-Oxide-Metal Au-Fe3O4-Au Single Nanowire Device For Spintronics, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna 2015 Boise State University

Heterojunction Metal-Oxide-Metal Au-Fe3O4-Au Single Nanowire Device For Spintronics, K. M. Reddy, Nitin P. Padture, Alex Punnoose, Charles Hanna

Physics Faculty Publications and Presentations

In this report, we present the synthesis of heterojunction magnetite nanowires in alumina template and describe magnetic and electrical properties from a single nanowire device for spintronics applications. Heterojunction Au-Fe-Au nanowire arrays were electrodeposited in porous aluminum oxide templates, and an extensive and controlled heat treatment process converted Fe segment to nanocrystalline cubic magnetite phase with well-defined Au-Fe3O4 interfaces as confirmed by the transmission electron microscopy. Magnetic measurements revealed Verwey transition shoulder around 120 K and a room temperature coercive field of 90 Oe. Current–voltage (I-V) characteristics of a single Au-Fe3O4-Au nanowire ...


Physics Education: Analysis Of The Effects Of I>Clicker Usage In The Gen Ed Classroom On Content Learning, Collin Mortensen 2015 Utah State University

Physics Education: Analysis Of The Effects Of I>Clicker Usage In The Gen Ed Classroom On Content Learning, Collin Mortensen

Physics Capstone Project

The modern classroom has a wide variety of tools and technology available as aids to assist in students’ content area learning. One of these tools which has gained increased popularity recently is the i>clicker, a remote device that allows students to answer questions posed by lecturers through media presentations such as PowerPoint. Lecturers are able to record and display the answers selected by the students in class, providing real-time feedback to students on material lectured on in class.

The goal of this study was to examine the effectiveness of the i>clicker device as an aid in content learning ...


Suitability Of Nickel Chromium Wire Cutters As Deployable Release Mechanisms On Cubesats In Low Earth Orbit, James Gardnier 2015 Utah State University

Suitability Of Nickel Chromium Wire Cutters As Deployable Release Mechanisms On Cubesats In Low Earth Orbit, James Gardnier

Physics Capstone Project

This paper investigates the suitability of a nickel chromium wire cutter (NCWC) for use on the GASPACS (Get Away Special Passive Attitude Control Satellite) Mission. It is intended that when activated the NCWC will cut through a restraining wire and thereby release the stored energy of the deployable AeroBoom. Flight worthiness is based on favorable performance during functional testing to address known issues with the NCWC, such as wire burn through and cutting issues. In-depth testing discussed in this paper includes: Manufacturability of the NCWC, including analysis of possible acceptable performance errors induced from inefficiencies in the assembly process, functional ...


Surface Microstructure Evolution Of Metallic Specimens Using The Large Chamber Scanning Electron Microscope, Grace Egbujor 2015 Western Kentucky University

Surface Microstructure Evolution Of Metallic Specimens Using The Large Chamber Scanning Electron Microscope, Grace Egbujor

Masters Theses & Specialist Projects

An initial study into the use of the large chamber scanning electron microscope (LCSEM) to interrogate the surface microstructure evolution of metallic specimens has been carried out. The LC-SEM located at Western Kentucky University is the largest instrument of its type at any university in the world. As such, unique measurements can be performed due to the size of its chamber and extended view of its optic system. Strain was varied for each individual specimen, and imaged using Secondary Electrons within the gauge length as well as near the grip position. Results will show progression of surface microstructures and nickel ...


So(8) Fermion Dynamical Symmetry In Graphene, Matthew Murphy 2015 University of Tennessee - Knoxville

So(8) Fermion Dynamical Symmetry In Graphene, Matthew Murphy

University of Tennessee Honors Thesis Projects

No abstract provided.


Generating Random Walks And Polygons With Thickness In Confinement, Sai Sindhuja Veeramachaneni 2015 Western Kentucky University

Generating Random Walks And Polygons With Thickness In Confinement, Sai Sindhuja Veeramachaneni

Masters Theses & Specialist Projects

Algorithms to generate walks (chains of unit-length, freely-jointed segments) and polygons (closed walks) in spherical confinements have been developed in the last few years. These algorithms generate polygons inside spherical confinement based on their mathematically derived probability distributions. The generated polygons do not occupy any volume { although that would be useful for some applications. This thesis investigates how to generate walks and polygons which occupy some volume in spherical confinement. More specifically, in this thesis, existing methods described in the literature have been studied and implemented to generate walks and polygons in confinement. Additionally, these methods were adapted to design ...


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