Digital Commons Network^™

Dynamics And Control Of Cable-Drogue System In Aerial Recovery Of Micro Air Vehicles Based On Gauss's Principle, Liang Sun, Randal W. Beard, Mark B. Colton, Timothy W. Mclain

Faculty Publications

This paper presents a new concept for aerial recovery of Micro Air Vehicles (ARMAVs) using a large mothership and a recovery drogue. The mothership drags a drogue attached to a cable and the drogue is controlled to match the flight patten of the MAV. This paper uses Gauss’s Principle to derive the dynamic model of the cable-drogue systems. A controllable drogue plays a key role in recovering MAVs in windy conditions. We develop a control approach for the drogue using its drag coefficient. Simulation results based on multilink cable-drogue systems present the feasibility of the aerial recovery concept and the …

Nondestructive Electromagnetic Material Characterization Using A Dual Waveguide Probe: A Full Wave Solution, Milo W. Hyde Iv, James W. Stewart, Michael J. Havrilla, William P. Baker, Edward Rothwell, Dennis P. Nyquist

Faculty Publications

A nondestructive technique for determining the complex permittivity and permeability of a perfect electric conductor backed magnetic shielding material using a dual waveguide probe is presented. The dual waveguide probe allows for the simultaneous collection of reflection and transmission coefficients which distinguishes it from single probe methods common in the literature. Theoretical development of these coefficients, which is accomplished through a coupled magnetic field integral equations formulation using Love's equivalence principle and solved via the method of moments (MOM), is discussed. Evaluation of the resulting MOM impedance matrix elements is performed using complex plane integration leading to enhanced computational efficiency …

Bounding Isotropic Lorentz Violation Using Synchrotron Losses At Lep, Brett David Altschul

Faculty Publications

Some deviations from special relativity—especially isotropic effects—are most efficiently constrained using particles with velocities very close to 1. While there are extremely tight bounds on some of the relevant parameters coming from astrophysical observations, many of these rely on our having an accurate understanding of the dynamics of these high-energy sources. It is desirable to have reliable laboratory constraints on these same parameters. The fastest-moving particles in a laboratory were electrons and positrons at LEP. The energetics of the LEP beams were extremely well understood, and measurements of the synchrotron emission rate indicate that the isotropic Lorentz violation coefficient |˜κ …

An Exploration Of Topologies And Communication In Large Particle Swarms, Matthew Gardner, Andrew Mcnabb, Kevin Seppi

Faculty Publications

Particle Swarm Optimization (PSO) has typically been used with small swarms of about 50 particles. However, PSO is more efficiently parallelized with large swarms. We formally describe existing topologies and identify variations which are better suited to large swarms in both sequential and parallel computing environments. We examine the performance of PSO for benchmark functions with respect to swarm size and topology. We develop and demonstrate a new PSO variant which leverages the unique strengths of large swarms. “Hearsay PSO” allows for information to flow quickly through the swarm, even with very loosely connected topologies. These loosely connected topologies are …

Time Domain Equalizer Design Using Bit Error Rate Minimization For Uwb Systems, Syed Imtiaz Husain, Jinhong Yuan, Jian Zhang, Richard K. Martin

Faculty Publications

Ultra-wideband (UWB) communication systems occupy huge bandwidths with very low power spectral densities. This feature makes the UWB channels highly rich in resolvable multipaths. To exploit the temporal diversity, the receiver is commonly implemented through a Rake. The aim to capture enough signal energy to maintain an acceptable output signal-to-noise ratio (SNR) dictates a very complicated Rake structure with a large number of fingers. Channel shortening or time domain equalizer (TEQ) can simplify the Rake receiver design by reducing the number of significant taps in the effective channel. In this paper, we first derive the bit error rate (BER) of …

Gamma-Ray Spectroscopy At Triumf-Isac: The New Frontier Of Radioactive Ion Beam Research, G. C. Ball, C. Andreoiu, R. A.E. Austin, D. Bandyopadhyay, J. A. Becker, P. Bricault, N. Brown, S. Chan, R. Churchman, S. Colosimo, H. Coombes, D. Cross, G. Demand, T. E. Drake, M. Dombsky, S. Ettenauer, P. Finlay, D. Furse, A. Garnsworthy, P. E. Garrett, K. L. Green, G. F. Grinyer, B. Hyland, G. Hackman, R. Kanungo, W. D. Kulp, J. Lassen, K. G. Leach, J. R. Leslie, C. Mattoon, D. Melconian, A. C. Morton, C. J. Pearson

Faculty Publications

High-resolution gamma-ray spectroscopy is essential to fully exploit the unique scientific opportunities at the next generation radioactive ion beam facilities such as the TRTUMF Isotope Separator and Accelerator (TSAC). At IS AC the 871 spectrometer and its associated auxiliary detectors is optimize for p-decay studies while TIGRESS an array of segmented clover HPGe detectors has been designed for studies with accelerated beams. This paper gives a brief overview of these facilities and also presents recent examples of the diverse experimental program carried out at the STI spectrometer. © 2009 American Institute of Physics.

Extending The Support Theorem To Infinite Dimensions, Jeremy J. Becnel

Faculty Publications

The Radon transform is one of the most useful and applicable tools in functional analysis. First constructed by John Radon in 1917 [9] it has now been adapted to several settings. One of the principle theorems involving the Radon transform is the Support Theorem. In this paper, we discuss how the Radon transform can be constructed in the white noise setting. We also develop a Support Theorem in this setting.

Uniform Global Asymptotic Stability Of A Class Of Adaptively Controlled Nonlinear Systems, Frédéric Mazenc, Marcio De Queiroz, Michael Malisoff

Faculty Publications

We give a new explicit, global, strict Lyapunov function construction for the error dynamics for adaptive tracking control problems, under an appropriate persistency of excitation condition. We then allow time-varying uncertainty in the unknown parameters. In this case, we construct input-to-state stable Lyapunov functions under suitable bounds on the uncertainty, provided the regressor also satisfies an affine growth condition. This lets us quantify the effects of uncertainties on both the tracking and the parameter estimation. We illustrate our results using Rössler systems. © 2009 IEEE.

Coloring Graphs With Crossings, Bogdan Oporowski, David Zhao

Faculty Publications

We generalize the Five-Color Theorem by showing that it extends to graphs with two crossings. Furthermore, we show that if a graph has three crossings, but does not contain K6 as a subgraph, then it is also 5-colorable. We also consider the question of whether the result can be extended to graphs with more crossings. © 2008 Elsevier B.V. All rights reserved.

Mapping The Dark Side With Deimos: Globular Clusters, X-Ray Gas, And Dark Matter In The Ngc 1407 Group, Aaron J. Romanowsky, J. Strader, L. Spitler, R. Johnson, J. P. Brodie, D. A. Forbes, T. Ponman

Faculty Publications

NGC 1407 is the central elliptical in a nearby evolved group of galaxies apparently destined to become a galaxy cluster core. We use the kinematics of globular clusters (GCs) to probe the dynamics and mass profile of the group's center, out to a radius of 60 kpc (~10 galaxy effective radii)—the most extended data set to date around an early-type galaxy. This sample consists of 172 GC line-of-sight velocities, most of them newly obtained using Keck/DEIMOS, with a few additional objects identified as dwarf-globular transition objects or as intragroup GCs. We find weak rotation for the outer parts of the …

A Pilgrimage Through English History And Culture (A-E), Gary P. Gillum, Susan Wheelwright O'Connor, Alexa Hysi

Faculty Publications

An Annotated Bibliography of Books Printed in England before 1700 and housed in the L. Tom Perry Special Collections Harold B. Lee Library.

Limit On The Diffuse Flux Of Ultrahigh Energy Tau Neutrinos With The Surface Detector Of The Pierre Auger Observatory, J. Abraham, P. Abreu, M. Aglietta, C. Aguirre, E. J. Ahn, D. Allard, I. Allekotte, J. Allen, P. Allison, J. Alvarez-Muñiz, M. Ambrosio, L. Anchordoqui, S. Andringa, A. Anzalone, C. Aramo, S. Argirò, K. Arisaka, F. Arneodo, F. Arqueros, T. Asch, H. Asorey, P. Assis, J. Aublin, M. Ave, G. Avila, T. Bäcker, D. Badagnani, K. B. Barber, A. F. Barbosa, S. L.C. Barroso, B. Baughman, P. Bauleo, J. J. Beatty

Faculty Publications

Data collected at the Pierre Auger Observatory are used to establish an upper limit on the diffuse flux of tau neutrinos in the cosmic radiation. Earth-skimming ντ may interact in the Earth's crust and produce a τ lepton by means of charged-current interactions. The τ lepton may emerge from the Earth and decay in the atmosphere to produce a nearly horizontal shower with a typical signature, a persistent electromagnetic component even at very large atmospheric depths. The search procedure to select events induced by τ decays against the background of normal showers induced by cosmic rays is described. The method …

A Pilgrimage Through English History And Culture, Gary P. Gillum, Susan Wheelwright O'Connor, Alexa Hysi

Faculty Publications

An Annotated Bibliography of Books Printed in England before 1700 and housed in the L. Tom Perry Special Collections Harold B. Lee Library.

Measurement Of Charged Current Deep Inelastic Scattering Cross Sections With A Longitudinally Polarised Electron Beam At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, F. Cindolo, M. Corradi, G. Iacobucci, A. Margotti, R. Nania, A. Polini, S. Antonelli, M. Basile, M. Bindi, L. Cifarelli, A. Contin, S. De Pasquale, G. Sartorelli, A. Zichichi, D. Bartsch, I. Brock, H. Hartmann

Faculty Publications

Measurements of the cross sections for charged current deep inelastic scattering in e - p collisions with longitudinally polarised electron beams are presented. The measurements are based on a data sample with an integrated luminosity of 175 pb-1 collected with the ZEUS detector at HERA at a centre-of-mass energy of 318 GeV. The total cross section is given for positively and negatively polarised electron beams. The differential cross-sections d σ/dQ 2, d σ/dx and d σ/dy are presented for Q 2>200 GeV2. The double-differential cross-section d 2 σ/dxdQ 2 is presented in the kinematic range 2802

My Two Boots ... A Walk Through The Wetlands. An Annual Outing For 700 Middle School Students, Julie Cwikla, Mark Lasalle, Sybil Wilner

Faculty Publications

No abstract provided.

Strategic Idealizations Of Science To Oppose Environmental Regulation" A Case Study Of Five Tmdl Controversies, David S. Caudill, Donald E. Curley

Faculty Publications

Proponents of environmental regulation have catalogued various strategies used by takeholders to delay or weaken regulatory efforts, including (1) manufacturing or magnifying uncertainty; (2) demanding “sound science” (and thereby imposing unreasonable standards of evidence); and (3) data quality initiatives that permit deconstruction of credible studies by highlighting inevitable assumptions, funding sources, and areas for further research. Such strategies can be termed “idealizations” of science insofar as they rely on an unrealistic image of good science as somehow capable of avoiding tentative conclusions, institutional interests, consensual assumptions, and the need for further research.

The question remains, however, when does an argument …

A Pilgrimage Through English History And Culture (M-S), Gary P. Gillum, Susan Wheelwright O'Connor, Alexa Hysi

Faculty Publications

An Annotated Bibliography of Books Printed in England before 1700 and housed in the L. Tom Perry Special Collections Harold B. Lee Library.

Ionic Selectivity In L-Type Calcium Channels By Electrostatics And Hard-Core Repulsion, Dezso Boda, Douglas Henderson, Monika Valisko, Bob Eisenberg, Dirk Gillespie

Faculty Publications

A physical model of selective "ion binding" in the L-type calcium channel is constructed, and consequences of the model are compared with experimental data. This reduced model treats only ions and the carboxylate oxygens of the EEEE locus explicitly and restricts interactions to hard-core repulsion and ion–ion and ion–dielectric electrostatic forces. The structural atoms provide a flexible environment for passing cations, thus resulting in a self-organized induced-fit model of the selectivity filter. Experimental conditions involving binary mixtures of alkali and/or alkaline earth metal ions are computed using equilibrium Monte Carlo simulations in the grand canonical ensemble. The model pore rejects …

The Risk Of Developing A Second Cancer After Receiving Craniospinal Proton Irradiation, Wayne D. Newhauser, Jonas D. Fontenot, Anita Mahajan, David Kornguth, Marilyn Stovall, Yuanshui Zheng, Phillip J. Taddei, Dragan Mirkovic, Radhe Mohan, James D. Cox, Shiao Woo

Faculty Publications

The purpose of this work was to compare the risk of developing a second cancer after craniospinal irradiation using photon versus proton radiotherapy by means of simulation studies designed to account for the effects of neutron exposures. Craniospinal irradiation of a male phantom was calculated for passively-scattered and scanned-beam proton treatment units. Organ doses were estimated from treatment plans; for the proton treatments, the amount of stray radiation was calculated separately using the Monte Carlo method. The organ doses were converted to risk of cancer incidence using a standard formalism developed for radiation protection purposes. The total lifetime risk of …

Mathematical Aspects Of Vacuum Energy On Quantum Graphs, G. Berkolaiko, J. M. Harrison, J. H. Wilson

Faculty Publications

We use quantum graphs as a model to study various mathematical aspects of the vacuum energy, such as convergence of periodic path expansions, consistency among different methods (trace formulae versus method of images) and the possible connection with the underlying classical dynamics. In our study we derive an expansion for the vacuum energy in terms of periodic paths on the graph and prove its convergence and smooth dependence on the bond lengths of the graph. For an important special case of graphs with equal bond lengths, we derive a simpler explicit formula. With minor changes this formula also applies to …

Environmentally Persistent Free Radicals Amplify Ultrafine Particle Mediated Cellular Oxidative Stress And Cytotoxicity, Shrilatha Balakrishna, Slawo Lomnicki, Kevin M. Mcavey, Richard B. Cole, Barry Dellinger, Stephania A. Cormier

Faculty Publications

Background: Combustion generated particulate matter is deposited in the respiratory tract and pose a hazard to the lungs through their potential to cause oxidative stress and inflammation. We have previously shown that combustion of fuels and chlorinated hydrocarbons produce semiquinone-type radicals that are stabilized on particle surfaces (i.e. environmentally persistent free radicals; EPFRs). Because the composition and properties of actual combustion-generated particles are complex, heterogeneous in origin, and vary from day-to-day, we have chosen to use surrogate particle systems. In particular, we have chosen to use the radical of 2-monochlorophenol (MCP230) as the EPFR because we have previously shown that …

Structure–Mutagenicity Relationships And Energies Of 1-, And 2-Nitrotriphenylenes [Abstract], Kefa Karimu Onchoke

Faculty Publications

No abstract provided.

Frequency Doubling And Memory Effects In The Spin Hall Effect, Yuriy V. Pershin Dr, Massimiliano Di Ventra

Faculty Publications

We predict that when an alternating voltage is applied to a semiconducting system with inhomogeneous electron density in the direction perpendicular to main current flow, the spin Hall effect results in a transverse voltage containing a double-frequency component. We also demonstrate that there is a phase shift between applied and transverse-voltage oscillations, related to the general memristive behavior of semiconductor spintronic systems. A different method to achieve frequency doubling based on the inverse spin Hall effect is also discussed.

Instabilities Of Naked Singularities And Black Hole Interiors In General Relativity, Gustavo Dotti, Reinaldo J. Gleiser, Jorge Pullin, Ignacio F. Ranea-Sandoval, Héctor Vucetich

Faculty Publications

Metrics representing black holes in General Relativity may exhibit naked singularities for certain values of their parameters. This is the case for super-extremal (J2 > M > 0) Kerr and super-extremal (|Q| > M > 0) Reissner-Nördstrom spacetimes, and also for the negative mass Schwarzschild spacetime. We review our recent work where we show that these nakedly singular spacetimes are unstable under linear gravitational perturbations, a result that supports the cosmic censorship conjecture, and also that the inner stationary region beyond the inner horizon of a Kerr black hole (J2 < M) is linearly unstable. © 2009 World Scientific Publishing Company.

Nutrient Enrichment Drives Gulf Of Mexico Hypoxia, Donald F. Boesch, Walter R. Boyton, Larry B. Crowder, Robert J. Diaz, Robert W. Howarth, Laurence D. Mee, Scott W. Nixon, Nancy N. Rabalais, Rutger Rosenberg, James G. Sanders, Donald Scavia, R. Eugene Turner

Faculty Publications

No abstract provided.

Controlled Assembly Of Rodlike Viruses With Polymers, Tao Li, Laying Wu, Nisaraporn Suthiwangcharoen, Michael A. Bruckman, Dayton Cash, Joan S. Hudson, Soumitra Ghoshroy, Qian Wang

Faculty Publications

A practical method to assemble rodlike tobacco mosaic virus and bacteriophage M13 with polymers was developed, which afforded a 3D core–shell composite with morphological control.

Intact And Top-Down Characterization Of Biomolecules And Direct Analysis Using Infrared Matrix-Assisted Laser Desorption Electrospray Ionization Coupled To Ft-Icr Mass Spectrometry, Jason S. Sampson, Kermit K. Murray, David C. Muddiman

Faculty Publications

We report the implementation of an infrared laser onto our previously reported matrix-assisted laser desorption electrospray ionization (MALDESI) source with ESI post-ionization yielding multiply charged peptides and proteins. Infrared (IR)-MALDESI is demonstrated for atmospheric pressure desorption and ionization of biological molecules ranging in molecular weight from 1.2 to 17 kDa. High resolving power, high mass accuracy single-acquisition Fourier transform ion cyclotron resonance (FT-ICR) mass spectra were generated from liquid- and solid-state peptide and protein samples by desorption with an infrared laser (2.94 μm) followed by ESI post-ionization. Intact and top-down analysis of equine myoglobin (17 kDa) desorbed from the solid …

Neutrino Flux Prediction At Miniboone, A. A. Aguilar-Arevalo, C. E. Anderson, A. O. Bazarko, S. J. Brice, B. C. Brown, L. Bugel, J. Cao, L. Coney, J. M. Conrad, D. C. Cox, A. Curioni, Z. Djurcic, D. A. Finley, B. T. Fleming, R. Ford, F. G. Garcia, G. T. Garvey, C. Green, J. A. Green, T. L. Hart, E. Hawker, R. Imlay, R. A. Johnson, G. Karagiorgi, P. Kasper, T. Katori, T. Kobilarcik, I. Kourbanis, S. Koutsoliotas, E. M. Laird, S. K. Linden, J. M. Link, Y. Liu

Faculty Publications

The booster neutrino experiment (MiniBooNE) searches for νμ→νe oscillations using the O(1GeV) neutrino beam produced by the booster synchrotron at the Fermi National Accelerator Laboratory). The booster delivers protons with 8 GeV kinetic energy (8.89GeV/c momentum) to a beryllium target, producing neutrinos from the decay of secondary particles in the beam line. We describe the Monte Carlo simulation methods used to estimate the flux of neutrinos from the beam line incident on the MiniBooNE detector for both polarities of the focusing horn. The simulation uses the Geant4 framework for propagating particles, accounting for electromagnetic processes and hadronic interactions in the …

On Connectedness Of Sets In The Real Spectra Of Polynomial Rings, F. Lucas, J. J. Madden, D. Schaub, M. Spivakovsky

Faculty Publications

Let R be a real closed field. The Pierce-Birkhoff conjecture says that any piecewise polynomial function f on R n can be obtained from the polynomial ring R[x 1,..., x n ] by iterating the operations of maximum and minimum. The purpose of this paper is threefold. First, we state a new conjecture, called the Connectedness conjecture, which asserts, for every pair of points α, β ε Sper R[x1,xn], the existence of connected sets in the real spectrum of R[x 1,..., x n ], satisfying certain conditions. We prove that the Connectedness conjecture implies the Pierce-Birkhoff conjecture. Secondly, we construct …

Existence And Uniqueness Of Solutions To The Backward 2d Stochastic Navier-Stokes Equations, P. Sundar, Hong Yin

Faculty Publications

The backward two-dimensional stochastic Navier-Stokes equations (BSNSEs, for short) with suitable perturbations are studied in this paper, over bounded domains for incompressible fluid flow. A priori estimates for adapted solutions of the BSNSEs are obtained which reveal a pathwise L∞ (H) bound on the solutions. The existence and uniqueness of solutions are proved by using a monotonicity argument for bounded terminal data. The continuity of the adapted solutions with respect to the terminal data is also established. © 2008 Elsevier B.V. All rights reserved.