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Missouri University of Science and Technology

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2004

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Articles 31 - 60 of 87

Full-Text Articles in Physical Sciences and Mathematics

Charge Transfer In Slow Collisions Of O⁸⁺ And Ar⁸⁺ Ions With H(1s) Below 2 Kev/Amu, Teck-Ghee Lee, M. Hesse, Anh-Thu Le, C. D. Lin Jul 2004

Charge Transfer In Slow Collisions Of O⁸⁺ And Ar⁸⁺ Ions With H(1s) Below 2 Kev/Amu, Teck-Ghee Lee, M. Hesse, Anh-Thu Le, C. D. Lin

Physics Faculty Research & Creative Works

We calculated the charge-transfer cross sections for O⁸⁺ + H collisions for energies from 1eV/amu to 2keV/amu, using the recently developed hyperspherical close-coupling method. In particular, the discrepancy for electron capture to the n = 6 states of O⁷⁺ from the previous theoretical calculations is further analyzed. Our results indicate that at low energies (below 100eV∕amu) electron capture to the n=6 manifold of O7+ becomes dominant. The present results are used to resolve the long-standing discrepancies from the different elaborate semiclassical calculations near 100eV/amu. We have also performed the semiclassical atomic orbital close-coupling calculations with straight-line trajectories. We found the …

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Sediments, Facies Tracts, And Variations In Sedimentation Rates Of Holocene Platform Carbonate Sediments And Associated Deposits, Northern Belize -- Implications For "Representative" Sedimentation Rates, Wan Yang, Salvatore J. Mazzullo, Chellie S. Teal Jul 2004

Sediments, Facies Tracts, And Variations In Sedimentation Rates Of Holocene Platform Carbonate Sediments And Associated Deposits, Northern Belize -- Implications For "Representative" Sedimentation Rates, Wan Yang, Salvatore J. Mazzullo, Chellie S. Teal

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In stratigraphic analysis and simulation, sedimentation rates are typically assumed to be constant for meter-scale sedimentation units of similar lithology. The rates of Holocene, shallow-marine carbonate and associated sediments within an 820 km2 area of Chetumal Bay in northern Belize were evaluated to test this assumption. Rates were determined from thickness data from 363 locations, durations derived from 14C age dates of mangrove peat on Pleistocene bedrock limestone and of overlying cerithid gravels, and reference to a sea-level curve for this area. The rate of entire Holocene sections (basal transgressive mangrove peat, shelly gravel, and overlying carbonate) varies …

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Neural Network Stabilizing Control Of Single Machine Power System With Control Limits, Wenxin Liu, Jagannathan Sarangapani, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Mariesa Crow Jul 2004

Neural Network Stabilizing Control Of Single Machine Power System With Control Limits, Wenxin Liu, Jagannathan Sarangapani, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

Power system stabilizers are widely used to generate supplementary control signals for the excitation system in order to damp out the low frequency oscillations. This paper proposes a stable neural network (NN) controller for the stabilization of a single machine infinite bus power system. In the power system control literature, simplified analytical models are used to represent the power system and the controller designs are not based on rigorous stability analysis. This work overcomes the two major problems by using an accurate analytical model for controller development and presents the closed-loop stability analysis. The NN is used to approximate the …

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Electronic Structure And Light-Induced Conductivity Of A Transparent Refractory Oxide, Julia E. Medvedeva, Arthur J. Freeman, Mariana I. Bertoni, Thomas O. Mason Jul 2004

Electronic Structure And Light-Induced Conductivity Of A Transparent Refractory Oxide, Julia E. Medvedeva, Arthur J. Freeman, Mariana I. Bertoni, Thomas O. Mason

Physics Faculty Research & Creative Works

Combined first-principles and experimental investigations reveal the underlying mechanism responsible for a drastic change of the conductivity (by 10 orders of magnitude) following hydrogen annealing and UV irradiation in a transparent oxide, 12CaO · 7Al2O3, found by Hayashi et al. [Nature (London) 419, 462 (2002).] The charge transport associated with photoexcitation of an electron from H- occurs by electron hopping.We identify the atoms participating in the hops, determine the exact paths for the carrier migration, estimate the temperature behavior of the hopping transport, and predict a way to enhance the conductivity by specific doping.

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Comparison Of Hyperspherical Versus Common-Reaction-Coordinate Close-Coupling Methods For Ion-Atom Collisions At Low Energies, Anh-Thu Le, C. D. Lin, L. F. Errea, L. Mendez, A. Riera, B. Pons Jun 2004

Comparison Of Hyperspherical Versus Common-Reaction-Coordinate Close-Coupling Methods For Ion-Atom Collisions At Low Energies, Anh-Thu Le, C. D. Lin, L. F. Errea, L. Mendez, A. Riera, B. Pons

Physics Faculty Research & Creative Works

We present detailed comparisons between the two quantal approaches--hyperspherical close-coupling and common-reaction-coordinate close-coupling methods--on an exemplary case of He²⁺ + H(1s) collisions at center-of-mass energy from 20eV up to 1.6keV. It is shown that the partial-wave charge-transfer cross sections from the two approaches agree very well at low energy below 200eV down to 30eV. This good agreement is a strong indication of the validity of both methods. The small difference at very low energies and the convergence with respect to the number of channels in both approaches at higher energies are also discussed.

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New Limits On The Drift Of Fundamental Constants From Laboratory Measurements, Marc P. Fischer, Nikolai N. Kolachevsky, Marcus Zimmermann, Ronald Holzwarth, Th H. Udem, Theodor Wolfgang Hansch, Michel Abgrall, Jan Grunert, Ivan Maksimovic, Sebastien Bize, Harold Marion, Franck Pereira M Dos Santos, Pierre Lemonde, Giorgio Santarelli, Ph Laurent, Andre Clairon, Christophe Salomon, Martin K. Haas, Ulrich D. Jentschura, Christoph H. Keitel Jun 2004

New Limits On The Drift Of Fundamental Constants From Laboratory Measurements, Marc P. Fischer, Nikolai N. Kolachevsky, Marcus Zimmermann, Ronald Holzwarth, Th H. Udem, Theodor Wolfgang Hansch, Michel Abgrall, Jan Grunert, Ivan Maksimovic, Sebastien Bize, Harold Marion, Franck Pereira M Dos Santos, Pierre Lemonde, Giorgio Santarelli, Ph Laurent, Andre Clairon, Christophe Salomon, Martin K. Haas, Ulrich D. Jentschura, Christoph H. Keitel

Physics Faculty Research & Creative Works

We have remeasured the absolute 1S-2S transition frequency νH in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a limit of (-29 ± 57) Hz for the drift of νH with respect to the ground state hyperfine splitting νCs in 133Cs. Combining this result with the recently published optical transition frequency in 199Hg+ against νCs and a microwave 87Rb and 133Cs clock comparison, we deduce separate limits on α˙ / α = (-0.9 &plusm; 2.9) x 10-15 yr-1 and the fractional time …

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Effects Of Microbial Processes On Electrolytic And Interfacial Electrical Properties Of Unconsolidated Sediments, Gamal Z. Abdal Aal, Estella A. Atekwana, Lee D. Slater, Eliot A. Atekwana Jun 2004

Effects Of Microbial Processes On Electrolytic And Interfacial Electrical Properties Of Unconsolidated Sediments, Gamal Z. Abdal Aal, Estella A. Atekwana, Lee D. Slater, Eliot A. Atekwana

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The effect of microbial processes on electrical properties of unconsolidated sediments was investigated in a laboratory experiment consisting of biotic and abiotic sand columns. The biotic column (nutrient, diesel and bacteria) showed (a) temporal increase in the real, imaginary, and surface conductivity, and (b) temporal decrease in the formation factor. The abiotic columns (nutrient; and nutrient and diesel) showed no significant changes. Increase in microbial population numbers, decrease in organic carbon source, nitrate, and sulfate and increase in dissolved inorganic carbon and fluid conductivity were indicative of microbial activity in the biotic column. We also measure relative increase in the …

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Characterization And Magnetic Properties Of Core/Shell Structured Fe/Au Nanoparticles, Sung-Jin Cho, Susan M. Kauzlarich, Justin Olamit, Kai Liu, Fernande Grandjean, Leïla Rebbouh, Gary J. Long Jun 2004

Characterization And Magnetic Properties Of Core/Shell Structured Fe/Au Nanoparticles, Sung-Jin Cho, Susan M. Kauzlarich, Justin Olamit, Kai Liu, Fernande Grandjean, Leïla Rebbouh, Gary J. Long

Chemistry Faculty Research & Creative Works

Au-coated Fe nanoparticles have been prepared by using a reverse micelle method through reduction of an aqueous solution. Characterizations have been carried out over time to probe the oxidation of Fe. Immediately after synthesis, the samples exhibit metallic conduction and a negative magnetoresistance, consistent with the presence of α-Fe. The temperature dependence of magnetization displays a maximum at a blocking temperature of around 150 K. After a period of 1 month, the samples exhibit insulating behavior, indicating the oxidation of the Fe core. Mössbauer spectroscopy indicates the presence of an α-Fe component and a broad distribution of local environments.

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A Magnetic And Mössbauer Spectral Study Of The Spin Reorientation In Ndfe₁₁Ti And Ndfe₁₁Th, Cristina Piquer, Fernande Grandjean, Olivier Isnard, Viorel Pop, Gary J. Long Jun 2004

A Magnetic And Mössbauer Spectral Study Of The Spin Reorientation In Ndfe₁₁Ti And Ndfe₁₁Th, Cristina Piquer, Fernande Grandjean, Olivier Isnard, Viorel Pop, Gary J. Long

Chemistry Faculty Research & Creative Works

The influence of hydrogenation on the spin reorientation in the presence of neodymium was investigated in NdFe11Ti and NdFe11TH. The magnetic properties of these compounds were determined by utilizing ac magnetic susceptibility, thermomagnetic, and iron-57 Mössbauer spectral analysis. It was found that the these compounds had two advantages as hard magnetic materials such as: a high iron content yielding high magnetization and a high Curie temperature. The investigation results show that these compounds undergo a spin-reorientation transition at ~185 K and at 100± K, from an axial magnetic phase at high temperature to a basal magnetic …

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Gravitational Energy Loss In High Energy Particle Collisions: Ultrarelativistic Plunge Into A Multidimensional Black Hole, Emanuele Berti, Marco Cavaglia, Leonardo Gualtieri Jun 2004

Gravitational Energy Loss In High Energy Particle Collisions: Ultrarelativistic Plunge Into A Multidimensional Black Hole, Emanuele Berti, Marco Cavaglia, Leonardo Gualtieri

Physics Faculty Research & Creative Works

We investigate the gravitational energy emission of an ultrarelativistic particle radially falling into a D-dimensional black hole. We numerically integrate the equations describing black hole gravitational perturbations and obtain the energy spectra, total energy, and angular distribution of the emitted gravitational radiation. The black hole quasinormal modes for scalar, vector, and tensor perturbations are computed in the WKB approximation. We discuss our results in the context of black hole production at the TeV scale.

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Close-Coupling And Distorted-Wave Calculations For Electron-Impact Excitation Of The (5p⁵6p) States Of Xenon, K. Bartschat, Anand Dasgupta, Don H. Madison Jun 2004

Close-Coupling And Distorted-Wave Calculations For Electron-Impact Excitation Of The (5p⁵6p) States Of Xenon, K. Bartschat, Anand Dasgupta, Don H. Madison

Physics Faculty Research & Creative Works

We report on a series of calculations for electron-impact excitation of the (5p56p) states in xenon from the ground state (5p6)1S0 . As in previous calculations for other noble-gas targets, we find strong evidence of channel coupling for all incident energies considered (between threshold and 200 eV ). Although qualitative agreement with the experimental results of Fons and Lin [Phys. Rev. A 58, 4603 (1998)] is achieved, severe quantitative discrepancies of sometimes more than a factor of 2 remain.

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Electron Self-Energy For Higher Excited S Levels, Ulrich D. Jentschura, Peter J. Mohr Jun 2004

Electron Self-Energy For Higher Excited S Levels, Ulrich D. Jentschura, Peter J. Mohr

Physics Faculty Research & Creative Works

A nonperturbative numerical evaluation of the one-photon electron self-energy for the 3S and 4S states with charge numbers Z=1 to 5 is described. The numerical results are in agreement with known terms in the expansion of the self-energy in powers of Zα.

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Sub-Supersolution Method For Quasilinear Parabolic Variational Inequalities, Siegfried Carl, Vy Khoi Le May 2004

Sub-Supersolution Method For Quasilinear Parabolic Variational Inequalities, Siegfried Carl, Vy Khoi Le

Mathematics and Statistics Faculty Research & Creative Works

This paper is about a systematic attempt to apply the sub-supersolution method to parabolic variational inequalities. We define appropriate concepts of sub-supersolutions and derive existence, comparison, and extremity results for such inequalities.

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Protonium Formation In The P̅-H Collision At Low Energies By A Diabatic Approach, M. Hesse, Anh-Thu Le, C. D. Lin May 2004

Protonium Formation In The P̅-H Collision At Low Energies By A Diabatic Approach, M. Hesse, Anh-Thu Le, C. D. Lin

Physics Faculty Research & Creative Works

We present a diabatization technique in combination with the recently developed hyperspherical close coupling (HSCC) method. In contrast to the strict diabatization, our simple diabatization procedure transforms only sharp avoided crossings in the adiabatic hyperspherical potential curves into real crossings. With this approach, the weak collision channels can be removed from the close-coupling calculations. This method is used to study the antiproton-hydrogen collision at low energies. In the case of a scaled down (anti)proton mass, we show that a 10-channel calculation is enough to obtain converged cross sections at low energies. The results also indicate that protonium formation occurs mostly …

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Dynamic Correction Of A Distorted Image Using A Photorefractive Polymeric Composite, Jeffrey G. Winiarz, Fassil Ghebremichael, Jayan Sanders Thomas, Gerald R. Meredith, Nasser N. Peyghambarian May 2004

Dynamic Correction Of A Distorted Image Using A Photorefractive Polymeric Composite, Jeffrey G. Winiarz, Fassil Ghebremichael, Jayan Sanders Thomas, Gerald R. Meredith, Nasser N. Peyghambarian

Chemistry Faculty Research & Creative Works

We demonstrate, for the first time, the dynamic correction of aberrated images in real-time using a polymeric composite with fast response times. The current novel experimental design is capable of restoring a phase aberrated, image carrying laser beam, to nearly its original quality. The ability to reconstruct images in real-time is demonstrated through the changing of the aberrating medium at various speeds. In addition, this technique allows for the correction of images in motion, demonstrated through the oscillatory movement of the resolution target. We also have demonstrated that important parameters of the materials in the study such as response times, …

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Self-Energy Correction To The Two-Photon Decay Width In Hydrogenlike Atoms, Ulrich D. Jentschura May 2004

Self-Energy Correction To The Two-Photon Decay Width In Hydrogenlike Atoms, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We investigate the guage invariance of the leading logarithmic radiative correction to the two-photon decay width in hydrogenlike atoms, was investigated. The effective treatment of the correction using a Lamb-shift led to the equivalent results in both the length and velocity gages. The relevant radiative corrections were found to be related to the energies that entered into the propagator denominators, to the Hamiltonian, to the wave functions, and to the energy conservation condition, that holds between two photons. The results show that the dominant radiative correction to the 2S two-photon decay width is about -2.020 536(α/π)(Zα)2 1n[(Zα)-2] …

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Comment On "Role Of The Ground State In Electron-Atom Double Ionization" [1] (Multiple Letters), Jamal Berakdar, Stephenie J. Jones, Don H. Madison Apr 2004

Comment On "Role Of The Ground State In Electron-Atom Double Ionization" [1] (Multiple Letters), Jamal Berakdar, Stephenie J. Jones, Don H. Madison

Physics Faculty Research & Creative Works

No abstract provided.

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Scaling Laws For Single And Multiple Electron Loss From Projectiles In Collisions With A Many-Electron Target, Antonio C. Santos, Robert D. Dubois Apr 2004

Scaling Laws For Single And Multiple Electron Loss From Projectiles In Collisions With A Many-Electron Target, Antonio C. Santos, Robert D. Dubois

Physics Faculty Research & Creative Works

Using measured cross sections, empirical scaling laws are extracted for projectile stripping induced by collisions with a many-electron target. by scaling both the cross sections and the impact velocities, it is shown that a single universal curve can be used to fit data for single and multiple electron loss from negative ions, neutral particles, and singly or multiply charged positive ions. The scaling applies to projectiles ranging from hydrogen to uranium and collision energies ranging from below keV∕u to hundreds of MeV∕u . At high energies, existing data are consistent with a v−1 impact velocity dependence for scaled velocities less …

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Tcp Performance Over Mobile Ad Hoc Networks: A Quantitative Study, Vaidyanathan Anantharaman, Seung Jong Park, Karthikeyan Sundaresan, Raghupathy Sivakumar Mar 2004

Tcp Performance Over Mobile Ad Hoc Networks: A Quantitative Study, Vaidyanathan Anantharaman, Seung Jong Park, Karthikeyan Sundaresan, Raghupathy Sivakumar

Computer Science Faculty Research & Creative Works

In this paper, we study the performance of the transmission control protocol (TCP) over mobile ad-hoc networks. We present a comprehensive set of simulation results and identify the key factors that impact TCP's performance over ad-hoc networks. We use a variety of parameters including link failure detection latency, route computation latency, packet level route unavailability index, and flow level route unavailability index to capture the impact of mobility. We relate the impact of mobility on the different parameters to TCP's performance by studying the throughput, loss-rate and retransmission timeout values at the TCP layer. We conclude from our results that …

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Doubly Differential Multiple Ionization Of Krypton By Positron And Electron Impact, Kay Dubois, Antonio C. Santos, Ahmad Hasan Mar 2004

Doubly Differential Multiple Ionization Of Krypton By Positron And Electron Impact, Kay Dubois, Antonio C. Santos, Ahmad Hasan

Physics Faculty Research & Creative Works

Measurements of doubly differential single and multiple ionization of krypton atoms have been performed for 750 eV positron and electron impact. Data were measured as a function of projectile energy-loss and scattering angle. For electrons, the energy-loss range was 0-85% of the initial projectile energy and scattering angles were between ±22°. Following the procedure adopted previously for argon, the electron impact data were placed on an absolute scale by normalizing to total ionization cross sections available in the literature. The present results for krypton show differences between positron and electron impact that are less pronounced than was found for argon. …

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Multiple Solutions For Quasilinear Elliptic Neumann Problems In Orlicz-Sobolev Spaces, Nikolaos Halidias, Vy Khoi Le Jan 2004

Multiple Solutions For Quasilinear Elliptic Neumann Problems In Orlicz-Sobolev Spaces, Nikolaos Halidias, Vy Khoi Le

Mathematics and Statistics Faculty Research & Creative Works

We investigate the existence of multiple solutions to quasilinear elliptic problems containing Laplace like operators (ϕ-Laplacians). We are interested in Neumann boundary value problems and our main tool is Brézis-Nirenberg's local linking theorem.

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Tid And See Testing Results Of Altera Cyclone Field Programmable Gate Array, Stephen L. Clark, K. Avery, R. Parker Jan 2004

Tid And See Testing Results Of Altera Cyclone Field Programmable Gate Array, Stephen L. Clark, K. Avery, R. Parker

Mathematics and Statistics Faculty Research & Creative Works

Total ionizing dose (TID) and single event effects testing was performed on Altera Cyclone FPGAs. The devices exhibit slight performance degradation to a TID of 1 Mrad (Si), but also exhibited single event latchup at a low LET.

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The Independence Of Characters On Nonabelian Groups, David E. Grow, Kathryn E. Hare Jan 2004

The Independence Of Characters On Nonabelian Groups, David E. Grow, Kathryn E. Hare

Mathematics and Statistics Faculty Research & Creative Works

We show that there are characters of compact, connected, nonabelian groups that approximate random choices of signs. The work was motivated by Kronecker's theorem on the independence of exponential functions and has applications to thin sets.

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Hereditarily Unicoherent Continua And Their Absolute Retracts, J. J. Charatonik, W. J. Charatonik, Janusz R. Prajs Jan 2004

Hereditarily Unicoherent Continua And Their Absolute Retracts, J. J. Charatonik, W. J. Charatonik, Janusz R. Prajs

Mathematics and Statistics Faculty Research & Creative Works

We investigate absolute retracts for classes of hereditarily unicoherent continua, tree-like continua, λ- dendroids, dendroids and some other related ones. The main results are: (1) the inverse limits of trees with confluent bonding mappings are absolute retracts of hereditarily unicoherent continua; (2) each tree-like continuum is embeddable in a special way in a tree-like absolute retract for the class of hereditarily unicoherent continua; (3) a dendroid is an absolute retract for hereditarily unicoherent continua if and only if it can be embedded as a retract into the Mohler-Nikiel universal smooth dendroid.

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Existence And Comparison Results For Quasilinear Evolution Hemivariational Inequalities, Siegfried Carl, Vy Khoi Le, Dumitru Motreanu Jan 2004

Existence And Comparison Results For Quasilinear Evolution Hemivariational Inequalities, Siegfried Carl, Vy Khoi Le, Dumitru Motreanu

Mathematics and Statistics Faculty Research & Creative Works

We generalize the sub-supersolution method known for weak solutions of single and multivalued nonlinear parabolic problems to quasilinear evolution hemivariational inequalities. To this end we first introduce our basic notion of sub- and supersolutions on the basis of which we then prove existence, comparison, compactness and extremality results for the hemivariational inequalities under considerations.

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Oscillation Of Second Order Nonlinear Dynamic Equations On Time Scales, S. H. Saker, Martin Bohner Jan 2004

Oscillation Of Second Order Nonlinear Dynamic Equations On Time Scales, S. H. Saker, Martin Bohner

Mathematics and Statistics Faculty Research & Creative Works

By means of Riccati transformation techniques, we establish some oscillation criteria for a second order nonlinear dynamic equation on time scales in terms of the coefficients. We give examples of dynamic equations to which previously known oscillation criteria are not applicable.

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Oscillation Theory For Second Order Dynamic Equations [Book Review], Martin Bohner Jan 2004

Oscillation Theory For Second Order Dynamic Equations [Book Review], Martin Bohner

Mathematics and Statistics Faculty Research & Creative Works

No abstract provided.

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Study Of Structural And Magnetic Properties Of Iron-Rich Mixed Rare-Earth Nddyfe (17-Y-X)Coxsiy Compounds, Kishore Kamaraju, Jinbo Yang, William B. Yelon, Oran Allan Pringle, M. S. Kim, Qingsheng Cai, William Joseph James Jan 2004

Study Of Structural And Magnetic Properties Of Iron-Rich Mixed Rare-Earth Nddyfe (17-Y-X)Coxsiy Compounds, Kishore Kamaraju, Jinbo Yang, William B. Yelon, Oran Allan Pringle, M. S. Kim, Qingsheng Cai, William Joseph James

Physics Faculty Research & Creative Works

A series of NdDyFe(17-y-x)CoxSiy solid solutions with = 2 and 3 and = 0.5 1.0 and 1.5 were prepared by induction melting stoichiometric amounts of high-purity elements. The postannealed samples consist of two phases belonging to the space groups R3 m and P63 mmc . The lattice parameters and the unit cell volumes were calculated from the refinements of the magnetic and structural unit cells using the FULLPROF version of the Rietveld program. For a fixed content of Co, the maximum Curie temperatures (305 C to 405 C) were observed in samples with = 1 and having two phases, a …

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Neural Network Controller For Manipulation Of Micro-Scale Objects, Vijayakumar Janardhan, Pingan He, Jagannathan Sarangapani Jan 2004

Neural Network Controller For Manipulation Of Micro-Scale Objects, Vijayakumar Janardhan, Pingan He, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement learning-based neural network (RLNN) controller is presented for the manipulation and handling of micro-scale objects in a microelectromechanical system (MEMS). In MEMS, adhesive, surface tension, friction and van der Waals forces are dominant. Moreover, these forces are typically unknown. The RLNN controller consists of an action NN for compensating the unkoown system dynamics, and a critic NN to tune the weights of the action NN. Using the Lyapunov approach, the uniformly ultimate houndedness (UUB) of the closed-loop tracking error and weight estimates are shown by using a novel weight updates. Simulation results are presented to substantiate the …

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Comprehensive Evaluation Of Animated Instructional Software For Mechanics Of Materials, Timothy A. Philpot, Richard H. Hall Jan 2004

Comprehensive Evaluation Of Animated Instructional Software For Mechanics Of Materials, Timothy A. Philpot, Richard H. Hall

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

During the past three years, the Basic Engineering Department at the University of Missouri--Rolla has been developing a second-generation suite of instructional software called MecMovies for the mechanics of materials course. In the Fall 2003 semester, MecMovies was integrated into assignments throughout the entire semester for one of the six UMR mechanics of materials sections. This paper presents a comparison of student performance in the experimental section with student performance in five control sections along with discussion of student qualitative ratings and comments.

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