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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 ...


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

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 ...


Model For Charge Injection With Electron Beams Into Highly Disordered Insulating Materials, JR Dennison, Alec M. Sim, Gregory Wilson 2015 Utah State Univesity

Model For Charge Injection With Electron Beams Into Highly Disordered Insulating Materials, Jr Dennison, Alec M. Sim, Gregory Wilson

Presentations

The Walden-Wintle model for charge injection and transport through highly disordered insulating materials has been extended to include charge injection with a charged particle beam. The original model is applicable to charge injection in a dielectric material from a pair of electrodes in a parallel-plate geometry. It provides a versatile approach to predict the time-dependent current at a rear grounded electrode and the incident surface voltage, as the injection current density evolves over time with the development of a space charge barrier near the injection electrode. The Walden-Wintle model has been applied to many standard cases including Fowler-Nordheim injection, Schottky ...


Dust Devils And Dustless Vortices On A Desert Playa Observed With Surface Pressure And Solar Flux Logging, Ralph D. Lorenz, Brian K. Jackson 2015 Johns Hopkins University Applied Physics Laboratory

Dust Devils And Dustless Vortices On A Desert Playa Observed With Surface Pressure And Solar Flux Logging, Ralph D. Lorenz, Brian K. Jackson

Physics Faculty Publications and Presentations

Dust devils are convective vortices rendered visible by lofted dust, and may be a significant means of injecting dust into the atmosphere, on both Earth and Mars. The fraction of vortices that are dust-laden is not well-understood, however. Here we report a May/June 2013 survey on a Nevada desert playa using small stations that record pressure and solar flux with high time resolution (2 Hz): these data allow detection of vortices and an estimate of the dust opacity of the subset of vortices that geometrically occult the sun. The encounter rate of vortex pressure drops of 0.3 hPa ...


Session D-4: Particle Physics, Peter Dong 2015 Illinois Mathematics and Science Academy

Session D-4: Particle Physics, Peter Dong

Professional Learning Day

Particle physics is generally seen as far too difficult, too abstract and mathematical, to teach at the high school level — which is a pity, since particle physics is most likely to get students interested in the subject (witness the response to the discovery of the Higgs boson). However, the day-to-day work of experimental particle physicists is remarkably understandable, even for high school students willing to do a little work. We will examine assignments given at IMSA in this vein, including a class-wide analysis that simulated the search for a super symmetric Higgs boson, and discuss how they worked. Attendees will ...


A Contribution Toward Better Understanding Of Overbanking Tendency In Fixed-Wing Aircraft, Nihad E. Daidzic 2015 AAR Aerospace Consulting, LLC

A Contribution Toward Better Understanding Of Overbanking Tendency In Fixed-Wing Aircraft, Nihad E. Daidzic

Journal of Aviation Technology and Engineering

The phenomenon of overbanking tendency for a rigid-body, fixed-wing aircraft is investigated. Overbanking tendency is defined as a spontaneous, unbalanced rolling moment that keeps increasing an airplane’s bank angle in steep turns and must be arrested by opposite aileron action. As stated by the Federal Aviation Administration, the overbanking tendency may lead to a loss of control, especially in instrument meteorological conditions. It was found in this study that the speed differential over wing halves in horizontal turns indeed creates a rolling moment that achieves maximum values for bank angles between 45 and 55 degrees. However, this induced rolling ...


Comment On “Universality Of Returning Electron Wave Packet In High-Order Harmonic Generation With Midinfrared Laser Pulses”, M. V. Frolov, N. L. Manakov, Wei-Hao Xiong, Liang-You Peng, J. Burgdörfer, Anthony F. Starace 2015 Voronezh State University, Russia

Comment On “Universality Of Returning Electron Wave Packet In High-Order Harmonic Generation With Midinfrared Laser Pulses”, M. V. Frolov, N. L. Manakov, Wei-Hao Xiong, Liang-You Peng, J. Burgdörfer, Anthony F. Starace

Anthony F. Starace Publications

In conclusion, we have shown that when the same definition for the HHG yield is used [cf. Eq. (1)], the results of Ref. [1] give the same scaling law found earlier in Refs. [2–5] for wavelengths λ ≤ 2 μm. We note that this latter scaling law can be obtained analytically by using results of the model developed in Ref. [6] for the description of short-pulse HHG spectra. These analytic results as well as new numerical TDSE results for longer wavelengths, λ ≤ 4 μm, will be published elsewhere.


The Spacetime Co-Torsion In Torsion-Free Biconformal Spaces, James Thomas Wheeler 2015 Utah State University

The Spacetime Co-Torsion In Torsion-Free Biconformal Spaces, James Thomas Wheeler

James Thomas Wheeler

In preceding studies, [TR Gamma minus, TR Gamma plus] we showed that the solution for the connection of flat biconformal space also solves the curved space field equations for the torsion and co-torsion. We continued this investigation with an attempt to solve the full set of torsion and co-torsion field equations, with only the assumption of vanishing torsion and the known form of the metric. We successfully reduced the torsion equations to a single equation. Here, we reduce that equation to its essential degrees of freedom. We find that the spacetime co-torsion is entirely determined by the scale vector and ...


Variation Of The Weyl Action, James Thomas Wheeler 2015 Utah State University

Variation Of The Weyl Action, James Thomas Wheeler

James Thomas Wheeler

We show how to vary the fourth order Weyl gravity action to derive the Bach equation.


Effect Of Eva Content Upon The Dielectric Properties In Ldpe-Eva Films, Innovative Research Publications IRP India, Hojjat, Amrollahi, Mahmood, Borhani 2015 Innovative Research Publications

Effect Of Eva Content Upon The Dielectric Properties In Ldpe-Eva Films, Innovative Research Publications Irp India, Hojjat, Amrollahi, Mahmood, Borhani

Innovative Research Publications IRP India

Low density polyethylene (LDPE) blends with different percentages of ethylene vinyl acetate polymer membranes were prepared by a hot press casting method. The effects of EVA content on the electrical properties of LDPE were studied. The results on the electrical properties revealed that the surface resistance, volume resistivity, and breakdown voltage of the LDPE decrease with EVA content and reach a minimum at a 30 wt% of EVA. Dielectric constant and dielectric loss factor were increased with increasing EVA content up to 30 wt% of EVA. It can be deduced that the electrical properties of LDPE are improved by blending ...


A Study Of Photon Trapping And The Ac Stark Effect In Photonic Crystals And Dispersive Materials, Iftekharul Haque 2015 The University of Western Ontario

A Study Of Photon Trapping And The Ac Stark Effect In Photonic Crystals And Dispersive Materials, Iftekharul Haque

University of Western Ontario - Electronic Thesis and Dissertation Repository

In this thesis, we study light-matter interaction in the contexts of coherent population trapping (CPT) and the ac Stark effect in nanoparticles embedded (doped) in two important classes of reservoirs -- photonic crystals and dispersive materials. These materials have gaps in their energy spectra and are studied widely due to their unusual optical properties and potential for novel applications. We consider that the reservoirs are doped with an ensemble of five-level nanoparticles, each with a single Λ core (consisting of a lower doublet and an upper energy level), which interact with both the host reservoir and external radiation fields. We have ...


Edge States And Quantum Hall Phases In Graphene, Pavlo Piatkovskyi 2015 The University of Western Ontario

Edge States And Quantum Hall Phases In Graphene, Pavlo Piatkovskyi

University of Western Ontario - Electronic Thesis and Dissertation Repository

The focus of this thesis is the dynamical symmetry breaking in monolayer and bilayer graphene in a magnetic field and the edge excitations in these systems. Due to the spin and valley degrees of freedom, the Coulomb interaction in graphene can lead to various broken-symmetry quantum Hall phases. The transport properties of each phase are affected by the low-energy edge excitations, and understanding the edge state properties can be crucial for identifying the true nature of the ground state. We study edge states in biased bilayer graphene in a magnetic field within the four-band continuum model. The analysis is done ...


Torsion Free Biconformal Spaces: Reducing The Torsion Field Equations, James Thomas Wheeler 2015 Utah State University

Torsion Free Biconformal Spaces: Reducing The Torsion Field Equations, James Thomas Wheeler

James Thomas Wheeler

Our goal is to solve the full set of torsion and co-torsion field equations of Euclidean biconformal space, with only the assumption of vanishing torsion. Here we begin by resolving the involution constraints, symmetry conditions and torsion field equation into a single equation for further study.


Statistical Variation Of Diverse Light Emission Measurements From Bisphenol/Amine Epoxy Under Energetic Electron Bombardment, Justin Christensen 2015 Utah State University

Statistical Variation Of Diverse Light Emission Measurements From Bisphenol/Amine Epoxy Under Energetic Electron Bombardment, Justin Christensen

Physics Capstone Project

Dielectric materials subjected to energetic electron fluxes can emit light in several forms. We have observed three distinct types of emissions: (i) short-duration (<1 ms), high-intensity electrostatic discharge (ESD) or “arc” events; (ii) intermediate-duration, high-intensity events which begin with a bright arc followed by an exponential decay of intensity (~10 to 100 s decay constant), termed “flares”; and (iii) long-duration, low-intensity emission, or cathodoluminescence, that continues as long as the electron flux is on. These events were studied for bulk samples of bisphenol/amine epoxy, using an electron gun with varying current densities (0.3 to 5 nA/cm2) and energies (12 to 40 keV) in a high vacuum chamber. Light emitted from the samples was measured with a high-sensitivity visible to near-infrared video camera. Results of the spatial and temporal extent for each type of event are presented as well as a discussion of how absolute spectral radiance and rates for each type of event are dependent on incident electron current density, energy, and power density and on material type, temperature, and thickness. Applications of this research to spacecraft charging and light emissions are discussed.


Class Of Unambiguous State Discrimination Problems Achievable By Separable Measurements But Impossible By Local Operations And Classical Communication, Scott M. Cohen 2015 Portland State University

Class Of Unambiguous State Discrimination Problems Achievable By Separable Measurements But Impossible By Local Operations And Classical Communication, Scott M. Cohen

Physics Faculty Publications and Presentations

We consider an infinite class of unambiguous quantum state discrimination problems on multipartite systems, described by Hilbert space H, of any number of parties. Restricting consideration to measurements that act only on H, we find the optimal global measurement for each element of this class, achieving the maximum possible success probability of 1/2 in all cases. This measurement turns out to be both separable and unique, and by our recently discovered necessary condition for local quantum operations and classical communication (LOCC) it is easily shown to be impossible by any finite-round LOCC protocol. We also show that, quite generally ...


Advantages Of A Finite Extensible Nonlinear Elastic Potential In Lattice Boltzmann Simulations, Tai-Hsien Wu, Dewei Qi 2015 Western Michigan University

Advantages Of A Finite Extensible Nonlinear Elastic Potential In Lattice Boltzmann Simulations, Tai-Hsien Wu, Dewei Qi

The Hilltop Review

A new structure, generalized lattice nonlinear spring model (GLNSM), which adopts non-linear FENE-LJ potential instead of harmonic potential, has been coupled with lattice Boltzmann simulation for solving fluid-solid interaction problem. In this article, a significant work is the relationship between the GLNSM (FENE-LJ potential) and Young’s modulus has been described in detail. A validation has also been presented to prove that GLNSM is reliable.


Variation Of The Linear Biconformal Action, James Thomas Wheeler 2015 Utah State University

Variation Of The Linear Biconformal Action, James Thomas Wheeler

All Physics Faculty Publications

We find the field equations of biconformal space in a basis adapted to Lagrangian submanifolds on which the restriction of the Killing metric is non-degenerate.


Studies In Torsion Free Biconformal Spaces. Case 2: \Gamma_{-} = 0, James Thomas Wheeler 2015 Utah State University

Studies In Torsion Free Biconformal Spaces. Case 2: \Gamma_{-} = 0, James Thomas Wheeler

All Physics Faculty Publications

We show that the solutions for the symmetric part of the connection in homogeneous biconformal space also satisfy the more general field equations of curved biconformal spaces in the case when \gamma_{-} = 0.


Studies In Torsion Free Biconformal Spaces, James Thomas Wheeler 2015 Utah State University

Studies In Torsion Free Biconformal Spaces, James Thomas Wheeler

All Physics Faculty Publications

We study whether the solutions for the symmetric part of the connection in homogeneous biconformal space also satisfy the more general field equation of curved biconformal spaces. We show that the six field equations for the torsion and co-torsion are satisfied by vanishing torsion together with the Lorentzian form of the metric when γ+ = 0.


Neutron Generation From 10mev Electron Beam To Produce Mo99, Innovative Research Publications IRP India, Borhani Zarandi, Mahmood, Tabbakh, Farshid, Amrollahi Bioki, Hojjat 2015 Innovative Research Publications

Neutron Generation From 10mev Electron Beam To Produce Mo99, Innovative Research Publications Irp India, Borhani Zarandi, Mahmood, Tabbakh, Farshid, Amrollahi Bioki, Hojjat

Innovative Research Publications IRP India

In this paper MCNP4C code has been used to simulate of the photonuclear interaction induced by 10MeV electron beam is an approach for generating the high intensity neutrons. Since the results are depended on the target material, the calculations are performed for the targets made of high z elements of Pb, Ta and W in a simple geometry.


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