Sample records for magnetic domain-wall motion

  1. Magnetic domain walls driven by interfacial phenomena

    E-Print Network [OSTI]

    Emori, Satoru

    2014-01-01T23:59:59.000Z

    A domain wall in a ferromagnetic material is a boundary between differently magnetized regions, and its motion provides a convenient scheme to control the magnetization state of the material. Domain walls can be confined ...

  2. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for technological development, repetitive pulse experiments also showed that many of the pulses gave smaller speeds or no movement at all, so that the current-driven motion...

  3. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic Vortices Print Soft magnetic, micron-sized thin-film structures with magnetic vortices are intriguing systems...

  4. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  5. Electrical signature of magnetic domain-wall dynamics

    E-Print Network [OSTI]

    Liu, Y.; Tretiakov, O. A.; Abanov, Artem.

    2011-01-01T23:59:59.000Z

    Current-induced domain-wall dynamics is studied in a thin ferromagnetic nanowire. The domain-wall dynamics is described by simple equations with four parameters. We propose a procedure to unambiguously determine these parameters by all...

  6. X-ray imaging of extended magnetic domain walls in Ni80Fe20 wires

    SciTech Connect (OSTI)

    Basu, S.; Fry, P. W.; Allwood, D. A.; Bryan, M. T.; Gibbs, M. R. J.; Schrefl, T.; Im, M.-Y.; Fischer, P.

    2009-06-20T23:59:59.000Z

    We have used magnetic transmission X-ray microscopy to image magnetization configurations in 700 nm wide Ni{sub 80}Fe{sub 20} planar wires attached to 'nucleation' pads Domain walls were observed to inject only across half of the wire width but extend to several micrometers in length. Magnetostatic interactions with adjacent wires caused further unusual domain wall behavior. Micromagnetic modeling suggests the extended walls have Neel-like structure along their length and indicates weaker exchange coupling than is often assumed. These observations explain previous measurements of domain wall injection and demonstrate that magnetic domain walls in larger nanowires cannot always be considered as localized entities.

  7. Spin-polarized transport through domain wall in magnetized graphene

    E-Print Network [OSTI]

    M. Khodas; I. A. Zaliznyak; D. E. Kharzeev

    2009-04-08T23:59:59.000Z

    Atomically thin two-dimensional layer of honeycomb crystalline carbon known as graphene is a promising system for electronics. It has a point-like Fermi surface, which is very sensitive to external potentials. In particular, Zeeman magnetic field parallel to the graphene layer splits electron bands and creates fully spin-polarized and geometrically congruent circular Fermi surfaces of particle and hole type. In the presence of electric field, particles and holes with opposite spins drift in opposite direction. These phenomena are likely to be of interest for developing graphene-based spintronic devices. A domain wall (DW) separating regions with opposite spin polarizations is a basic element of such a device. Here we consider a ballistic passage of spin-polarized charge carriers through DW in graphene. We also discuss the analogy between the generation of spin currents in graphene and in relativistic quark-gluon plasma, where the spin-polarized current is responsible for the phenomenon of charge separation studied recently at RHIC.

  8. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  9. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  10. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  11. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  12. Pinning induced by inter-domain wall interactions in planar magnetic nanowires

    SciTech Connect (OSTI)

    Hayward, T.J.; Bryan, M.T.; Fry, P.W.; Fundi, P.M.; Gibbs, M.R.J.; Allwood, D.A.; Im, M.-Y.; Fischer, P.

    2009-10-30T23:59:59.000Z

    We have investigated pinning potentials created by inter-domain wall magnetostatic interactions in planar magnetic nanowires. We show that these potentials can take the form of an energy barrier or an energy well depending on the walls' relative monopole moments, and that the applied magnetic fields required to overcome these potentials are significant. Both transverse and vortex wall pairs are investigated and it is found that transverse walls interact more strongly due to dipolar coupling between their magnetization structures. Simple analytical models which allow the effects of inter-domain wall interactions to be estimated are also presented.

  13. Faster motion of double 360° domain walls system induced by spin-polarized current

    SciTech Connect (OSTI)

    Zhang, S. F.; Zhu, Q. Y.; Mu, C. P.; Zheng, Q.; Liu, X. Y.; Liu, Q. F.; Wang, J. B., E-mail: wangjb@lzu.edu.cn [Institute of Applied Magnetics, Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

    2014-05-07T23:59:59.000Z

    By micromagnetic simulation, we investigated a double 360° domain walls system in two parallel nanowires. Two domain walls are coupled to each other via magnetostatic interaction. When a spin-polarized current is applied to only one nanowire or both nanowires with the same direction, the two domain walls propagate along nanowires together. The critical velocity of such system is obviously higher than that of a single 360° domain wall. The interaction between the two domain walls can be modeled as two bodies that connected by a spring, and we analyzed the coupling characteritics of the double 360° domain walls at last.

  14. Magnetic domain wall propagation in a submicron spin-valve stripe: influence of the pinned layer

    E-Print Network [OSTI]

    Boyer, Edmond

    1/10 Magnetic domain wall propagation in a submicron spin-valve stripe: influence of the pinned ferromagnetic spin-valve stripe is investigated using giant magnetoresistance. A notch in the stripe efficiently generated in the vicinity of the notch by the pinned layer of the spin-valve. PACS: 72.25.Ba; 73.43.Qt; 75

  15. Phase diagram of magnetic domain walls in spin valve nano-stripes N. Rougemaille,1

    E-Print Network [OSTI]

    Boyer, Edmond

    Phase diagram of magnetic domain walls in spin valve nano-stripes N. Rougemaille,1 V. Uhlí,2, 1 O walls in Co/Cu/Py spin valve nano-stripes (Py: Permalloy), in which the Co layer is mostly single domain Magneto- Resistance. These stacking are called spin valve for a metal spacer layer, and pseudo spin valve

  16. Suppression of stochastic pinning in magnetic nanowire devices using “virtual” domain walls

    SciTech Connect (OSTI)

    Hodges, M. P. P.; Hayward, T. J. [Department of Materials Science and Engineering, University of Sheffield, Sheffield (United Kingdom); Bryan, M. T. [Department of Cardiovascular Science, University of Sheffield, Sheffield (United Kingdom); Fry, P. W. [Nanoscience and Technology Centre, University of Sheffield, Sheffield (United Kingdom); Im, M.-Y. [Center for X-ray Optics, Lawrence Berkeley National Lab, Berkeley, California 94720 (United States); Daegu Gyeongbuk Institute of Science and Technology, Daegu 711-873 (Korea, Republic of); Fischer, P. [Center for X-ray Optics, Lawrence Berkeley National Lab, Berkeley, California 94720 (United States); Department of Physics, University of California, Santa Cruz, California 94056 (United States)

    2014-09-28T23:59:59.000Z

    We have investigated the pinning and depinning of “virtual” domain walls in planar magnetic nanowires. Such virtual walls are created when a conventional domain wall becomes annihilated at a narrow gap between two segments of a discontinuous nanowire. By using focused magneto-optical Kerr effect magnetometry to study the repeatability of their depinning, we show that virtual walls exhibit single-mode depinning distributions, characterized by remarkably low, sub-Oersted standard deviations. This is in stark contrast to the depinning of domain walls from conventional notch-shaped defects, which typically exhibit multi-mode depinning field distributions spanning tens to hundreds of Oersteds. High-resolution magnetic soft x-ray microscopy measurements are used to reveal that this high level of repeatability is the result of a simple mediated-nucleation process, which decouples the depinning mechanism from structure of the initially injected DWs. Our work serves as an example of how the complex and dynamical stochastic behaviors exhibited by domain walls in nanowires can be controlled.

  17. Ratchet propagation of a magnetic domain wall in a single magnetic wire with quantum interference

    E-Print Network [OSTI]

    Yamaguchi, Akinobu; Miyajima, Hideki

    2010-01-01T23:59:59.000Z

    Quantum interference incorporating spatially asymmetric potential profiles is realized experimentally to manipulate a magnetic domain wall (DW) into a single multilayered wire whose spacer has a thickness gradient for generating asymmetrical interlayer exchange coupling from side to side. We demonstrate experimentally how to guide a DW in a micron-scale ferromagnetic wire without reflection symmetry of the interlayer exchange coupling. This is the ratcheting of a DW in a form of ratchet potential using quantum interference. The experimental results can be described well by numerical simulations considering spatially asymmetric potential profiles due to quantum interference.

  18. Ratchet propagation of a magnetic domain wall in a single magnetic wire with quantum interference

    E-Print Network [OSTI]

    Akinobu Yamaguchi; Tomoaki Kishimoto; Hideki Miyajima

    2010-07-13T23:59:59.000Z

    Quantum interference incorporating spatially asymmetric potential profiles is realized experimentally to manipulate a magnetic domain wall (DW) into a single multilayered wire whose spacer has a thickness gradient for generating asymmetrical interlayer exchange coupling from side to side. We demonstrate experimentally how to guide a DW in a micron-scale ferromagnetic wire without reflection symmetry of the interlayer exchange coupling. This is the ratcheting of a DW in a form of ratchet potential using quantum interference. The experimental results can be described well by numerical simulations considering spatially asymmetric potential profiles due to quantum interference.

  19. Domain wall displacement in Py square ring for single nanometric magnetic bead detection

    E-Print Network [OSTI]

    Vavassori, P; Gobbi, M; Donolato, M; Cantoni, M; Bertacco, R

    2008-01-01T23:59:59.000Z

    A new approach based on the domain wall displacement in confined ferromagnetic nanostructures for attracting and sensing a single nanometric magnetic particles is presented. We modeled and experimentally demonstrated the viability of the approach using an anisotropic magnetoresistance device made by a micron-size square ring of Permalloy designed for application in magnetic storage. This detection concept can be suitable to biomolecular recognition, and in particular to single molecule detection.

  20. Domain walls riding the wave.

    SciTech Connect (OSTI)

    Karapetrov, G.; Novosad, V.; Materials Science Division

    2010-11-01T23:59:59.000Z

    Recent years have witnessed a rapid proliferation of electronic gadgets around the world. These devices are used for both communication and entertainment, and it is a fact that they account for a growing portion of household energy consumption and overall world consumption of electricity. Increasing the energy efficiency of these devices could have a far greater and immediate impact than a gradual switch to renewable energy sources. The advances in the area of spintronics are therefore very important, as gadgets are mostly comprised of memory and logic elements. Recent developments in controlled manipulation of magnetic domains in ferromagnet nanostructures have opened opportunities for novel device architectures. This new class of memories and logic gates could soon power millions of consumer electronic devices. The attractiveness of using domain-wall motion in electronics is due to its inherent reliability (no mechanical moving parts), scalability (3D scalable architectures such as in racetrack memory), and nonvolatility (retains information in the absence of power). The remaining obstacles in widespread use of 'racetrack-type' elements are the speed and the energy dissipation during the manipulation of domain walls. In their recent contribution to Physical Review Letters, Oleg Tretiakov, Yang Liu, and Artem Abanov from Texas A&M University in College Station, provide a theoretical description of domain-wall motion in nanoscale ferromagnets due to the spin-polarized currents. They find exact conditions for time-dependent resonant domain-wall movement, which could speed up the motion of domain walls while minimizing Ohmic losses. Movement of domain walls in ferromagnetic nanowires can be achieved by application of external magnetic fields or by passing a spin-polarized current through the nanowire itself. On the other hand, the readout of the domain state is done by measuring the resistance of the wire. Therefore, passing current through the ferromagnetic wire is the preferred method, as it combines manipulation and readout of the domain-wall state. The electrons that take part in the process of readout and manipulation of the domain-wall structure in the nanowire do so through the so-called spin transfer torque: When spin-polarized electrons in the ferromagnet nanowire pass through the domain wall they experience a nonuniform magnetization, and they try to align their spins with the local magnetic moments. The force that the electrons experience has a reaction force counterpart that 'pushes' the local magnetic moments, resulting in movement of the domain wall in the direction of the electron flow through the spin-transfer torque. The forces between the electrons and the local magnetic moments in the ferromagnet also create additional electrical resistance for the electrons passing through the domain wall. By measuring resistance across a segment of the nanowire, one determines if a domain wall is present; i.e., one can read the stored information. The interaction of the spin-polarized electrons with the domain wall in the ferromagnetic nanowire is not very efficient. Even for materials achieving high polarization of the free electrons, it is very difficult to move the magnetic domain wall. Several factors contribute to this problem, with imperfections of the ferromagnetic nanowire that cause domain-wall pinning being the dominant one. Permalloy nanowires, one of the best candidates for domain-wall-based memory and logic devices, require current densities of the order of 10{sup 8} A/cm{sup 2} in order to move a domain wall from a pinning well. Considering that this current has to pass through a relatively long wire, it is not very difficult to imagine that most of the energy will go to Joule heating. The efficiency of the process - the ratio of the energy converted to domain-wall motion to the total energy consumed - is comparable to that of an incandescent light bulb converting electricity to light. A step towards more efficient domain-wall-based memory devices is the advance of using alternating currents or curren

  1. Droplet Nucleation and Domain Wall Motion in a Bounded Interval Robert S. Maier

    E-Print Network [OSTI]

    Maier, Robert S.

    magnetization. In the weak-noise limit, noise-activated magnetization reversals become exponentially rare, the reversal rate being given by the Kramers formula "!$#&% ')(1032547698 . Here 6 is the noise strength, 0 study a spatially extended model of noise-induced magne- tization reversal: a classical Ginzburg

  2. DOMAIN WALL MOTION IN R. WIESER # , U. NOWAK and K. D. USADEL

    E-Print Network [OSTI]

    Usadel, K. D.

    nanowires are possible candidates for patterned magnetic storage media (Ross et al. (2000); Nielsch et al. (2002)). For these nanowires and also for other future magneto­electronic devices the understanding.: +49 203 379 2969, fax: +49 203 379 3665, email: robert@thp.uni­duisburg.de 1 #12; of the nanostructure

  3. Axion domain wall baryogenesis

    E-Print Network [OSTI]

    Daido, Ryuji; Takahashi, Fuminobu

    2015-01-01T23:59:59.000Z

    We propose a new scenario of baryogenesis, in which annihilation of axion domain walls generates a sizable baryon asymmetry. Successful baryogenesis is possible for a wide range of the axion mass and decay constant, $m \\simeq 10^8 -10^{13}$ GeV and $f \\simeq 10^{13} - 10^{16}$ GeV. Baryonic isocurvature perturbations are significantly suppressed in our model, in contrast to various spontaneous baryogenesis scenarios in the slow-roll regime. In particular, the axion domain wall baryogenesis is consistent with high-scale inflation which generates a large tensor-to-scalar ratio within the reach of future CMB B-mode experiments. We also discuss the gravitational waves produced by the domain wall annihilation and its implications for the future gravitational wave experiments.

  4. Current-driven Domain Wall Dynamics And Its Electric Signature In Ferromagnetic Nanowires

    E-Print Network [OSTI]

    Liu, Yang

    2012-10-19T23:59:59.000Z

    We study current-induced domain wall dynamics in a thin ferromagnetic nanowire. We derive the effective equations of domain wall motion, which depend on the wire geometry and material parameters. We describe the procedure to determine...

  5. Domain wall mobility in nanowires: transverse versus vortex walls R. Wieser, U. Nowak and K. D. Usadel

    E-Print Network [OSTI]

    Usadel, K. D.

    Arrays of magnetic nanowires are possible candidates for patterned magnetic storage media [1, 2]. For these nanowires and also for other future magneto­electronic devices the understanding of domain wall motion and mobility is important for the controlled switching of the nanostructure. In a recent experiment

  6. Domain walls in gapped graphene

    E-Print Network [OSTI]

    G. W. Semenoff; V. Semenoff; Fei Zhou

    2008-05-31T23:59:59.000Z

    The electronic properties of a particular class of domain walls in gapped graphene are investigated. We show that they can support mid-gap states which are localized in the vicinity of the domain wall and propagate along its length. With a finite density of domain walls, these states can alter the electronic properties of gapped graphene significantly. If the mid-gap band is partially filled,the domain wall can behave like a one-dimensional metal embedded in a semi-conductor, and could potentially be used as a single-channel quantum wire.

  7. Domain walls in gapped graphene

    E-Print Network [OSTI]

    Semenoff, G W; Zhou, Fei

    2015-01-01T23:59:59.000Z

    The electronic properties of a particular class of domain walls in gapped graphene are investigated. We show that they can support mid-gap states which are localized in the vicinity of the domain wall and propagate along its length. With a finite density of domain walls, these states can alter the electronic properties of gapped graphene significantly. If the mid-gap band is partially filled,the domain wall can behave like a one-dimensional metal embedded in a semi-conductor, and could potentially be used as a single-channel quantum wire.

  8. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

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  9. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

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  10. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

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  11. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

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  12. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  13. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

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  14. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

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  15. X-Ray Imaging Current-Driven Magnetic Domain-Wall Motion in Nanowires

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  16. PHYSICAL REVIEW B 84, 115210 (2011) Spin torque and charge resistance of ferromagnetic semiconductor 2 and domain walls

    E-Print Network [OSTI]

    Flatte, Michael E.

    2011-01-01T23:59:59.000Z

    transport across the domain wall is possible, such as for magnetic semiconductor domain walls (whose walls model of a magnetic semiconductor, whose electronic structure is described with a Stoner model and whose

  17. Versatile magneto-optic Kerr effect polarimeter for studies of domain-wall dynamics in magnetic nanostructures

    E-Print Network [OSTI]

    Erskine, James L.

    and magnetic energy loss measurements spanning ten decades of drive frequency; spatially and temporally ns rise time or by electric currents from dc to 10 GHz. A detailed description of the instrument based on the MOKE. Pump-probe techniques7­15 that utilize magneto-optical sampling and ultrashort

  18. Propagating and reflecting of spin wave in permalloy nanostrip with 360° domain wall

    SciTech Connect (OSTI)

    Zhang, Senfu; Mu, Congpu; Zhu, Qiyuan; Zheng, Qi; Liu, Xianyin; Wang, Jianbo; Liu, Qingfang, E-mail: liuqf@lzu.edu.cn [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China)

    2014-01-07T23:59:59.000Z

    By micromagnetic simulation, we investigated the interaction between propagating spin wave (or magnonic) and a 360° domain wall in a nanostrip. It is found that propagating spin wave can drive a 360° domain wall motion, and the velocity and direction are closely related to the transmission coefficient of the spin wave of the domain wall. When the spin wave passes through the domain wall completely, the 360° domain wall moves toward the spin wave source. When the spin wave is reflected by the domain wall, the 360° domain wall moves along the spin wave propagation direction. Moreover, when the frequency of the spin wave is coincident with that of the 360° domain wall normal mode, the 360° domain wall velocity will be resonantly enhanced no matter which direction the 360 DW moves along. On the other hand, when the spin wave is reflected from the moving 360° domain wall, we observed the Doppler effect clearly. After passing through a 360° domain wall, the phase of the spin wave is changed, and the phase shift is related to the frequency. Nevertheless, phase shift could be manipulated by the number of 360° domain walls that spin wave passing through.

  19. Effective Supergravity for Supergravity Domain Walls

    E-Print Network [OSTI]

    M. Cvetic; N. D. Lambert

    2002-05-23T23:59:59.000Z

    We discuss the low energy effective action for the Bosonic and Fermionic zero-modes of a smooth BPS Randall-Sundrum domain wall, including the induced supergravity on the wall. The result is a pure supergravity in one lower dimension. In particular, and in contrast to non-gravitational domain walls or domain walls in a compact space, the zero-modes representing transverse fluctuations of domain wall have vanishing action.

  20. Droplet Nucleation and Domain Wall Motion in a Bounded Interval Robert S. Maier 1;2 and D. L. Stein 2;1

    E-Print Network [OSTI]

    Maier, Robert S.

    and negative magnetization. In the weak­noise limit, noise­activated magnetization reversals become exponentially rare, the reversal rate being given by the Kramers formula \\Gamma ¸ \\Gamma 0 exp], who worked out a `large deviation theory' of its magnetization reversals, but did not compute

  1. DefectDomain Wall Interactions in Trigonal

    E-Print Network [OSTI]

    Gopalan, Venkatraman

    Defect­Domain Wall Interactions in Trigonal Ferroelectrics Venkatraman Gopalan,1 Volkmar Dierolf,2 walls in the trigonal ferroelectrics lithium niobate and lithium tantalate. It is shown that extrinsic questions re- garding intrinsic widths, defect­domain wall interactions, and static versus dynamic wall

  2. Domain wall cosmology and multiple accelerations

    SciTech Connect (OSTI)

    Lee, Bum-Hoon [CQUeST, Sogang University, Seoul, Korea 121-742 (Korea, Republic of); Department of Physics, Sogang University, Seoul, 121-742 (Korea, Republic of); Lee, Wonwoo; Nam, Siyoung; Park, Chanyong [CQUeST, Sogang University, Seoul, 121-742 (Korea, Republic of)

    2007-05-15T23:59:59.000Z

    We classify the cosmological behaviors of the domain wall under junctions between two spacetimes in terms of various parameters: cosmological constants of bulk spacetime, a tension of a domain wall, and mass parameters of the black-hole-type metric. Especially, we consider the false-true vacuum-type junctions and the domain wall connecting between an inner AdS space and an outer AdS Reissner-Nordstroem black hole. We find that there exists a solution to the junction equations with multiple accelerations.

  3. Electric field control of domain wall propagation in Pt/Co/GdOx films

    E-Print Network [OSTI]

    Bauer, Uwe

    The influence of a gate voltage on domain wall (DW) propagation is investigated in ultrathin Pt/Co/gadolinium oxide (GdOx) films with perpendicular magnetic anisotropy. The DW propagation field can be enhanced or retarded ...

  4. Thermodynamics of free Domain Wall fermions

    E-Print Network [OSTI]

    R. V. Gavai; Sayantan Sharma

    2008-11-19T23:59:59.000Z

    Studying various thermodynamic quantities for the free domain wall fermions for both finite and infinite fifth dimensional extent N_5, we find that the lattice corrections are minimum for $N_T\\geq10$ for both energy density and susceptibility, for its irrelevant parameter M in the range 1.45-1.50. The correction terms are, however, quite large for small lattice sizes of $N_T\\leq8$. We propose modifications of the domain wall operator, as well as the overlap operator, to reduce the finite cut-off effects to within 10% of the continuum results of the thermodynamic quantities for the currently used N_T=6-8 lattices. Incorporating chemical potential, we show that \\mu^2 divergences are absent for a large class of such domain wall fermion actions although the chiral symmetry is broken for $\\mu\

  5. Standing gravitational waves from domain walls

    SciTech Connect (OSTI)

    Gogberashvili, Merab [Andronikashvili Institute of Physics, 6 Tamarashvili Street, Tbilisi 0177 (Georgia); Javakhishvili Tbilisi State University, 3 Chavchavadze Avenue, Tbilisi 0128 (Georgia); California State University, Fresno, Physics Department, Fresno, California 93740-8031 (United States); Myrzakul, Shynaray [Department of General and Theoretical Physics, Gumilev Eurasian National University, Astana, 010008 (Kazakhstan); California State University, Fresno, Physics Department, Fresno, California 93740-8031 (United States); Singleton, Douglas [California State University, Fresno, Physics Department, Fresno, California 93740-8031 (United States); Institute of Gravitation and Cosmology, Peoples' Friendship University of Russia, Moscow 117198 (Russian Federation)

    2009-07-15T23:59:59.000Z

    We construct a plane symmetric, standing gravitational wave for a domain wall plus a massless scalar field. The scalar field can be associated with a fluid which has the properties of 'stiff' matter, i.e., matter in which the speed of sound equals the speed of light. Although domain walls are observationally ruled out in the present era, the solution has interesting features which might shed light on the character of exact nonlinear wave solutions to Einstein's equations. Additionally this solution may act as a template for higher dimensional 'brane-world' model standing waves.

  6. Quantitative determination of vortex core dimensions in head-to-head domain walls using off-axis electron holography

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    transformations.7 Recent experimental reports confirm these predictions of domain wall movement8Quantitative determination of vortex core dimensions in head-to-head domain walls using off-dimensional characterization of vortex core spin structures, which is important for future magnetic data storage based

  7. Domain wall partition functions and KP

    E-Print Network [OSTI]

    O Foda; M Wheeler; M Zuparic

    2009-01-15T23:59:59.000Z

    We observe that the partition function of the six vertex model on a finite square lattice with domain wall boundary conditions is (a restriction of) a KP tau function and express it as an expectation value of charged free fermions (up to an overall normalization).

  8. Solitons and Domain Walls in Odd Dimensions

    E-Print Network [OSTI]

    N. D. Lambert; G. W. Gibbons

    2000-07-04T23:59:59.000Z

    We discuss the existance of smooth soliton solutions which interpolate between supersymmetric vacua in odd-dimensional theories. In particular we apply this analysis to a wide class of supergravities to argue against the existence of smooth domain walls interpolating between supersymmetric vacua. We find that if the superpotential changes sign then any Goldstino modes will diverge.

  9. Quantum Fusion of Domain Walls with Fluxes

    E-Print Network [OSTI]

    S. Bolognesi; M. Shifman; M. B. Voloshin

    2009-07-20T23:59:59.000Z

    We study how fluxes on the domain wall world volume modify quantum fusion of two distant parallel domain walls into a composite wall. The elementary wall fluxes can be separated into parallel and antiparallel components. The parallel component affects neither the binding energy nor the process of quantum merger. The antiparallel fluxes, instead, increase the binding energy and, against naive expectations, suppress quantum fusion. In the small flux limit we explicitly find the bounce solution and the fusion rate as a function of the flux. We argue that at large (antiparallel) fluxes there exists a critical value of the flux (versus the difference in the wall tensions), which switches off quantum fusion altogether. This phenomenon of flux-related wall stabilization is rather peculiar: it is unrelated to any conserved quantity. Our consideration of the flux-related all stabilization is based on substantiated arguments that fall short of complete proof.

  10. Light quark masses using domain wall fermions

    E-Print Network [OSTI]

    Tom Blum; Amarjit Soni; Matthew Wingate

    1998-09-10T23:59:59.000Z

    We compute the one-loop self-energy correction to the massive domain wall quark propagator. Combining this calculation with simulations at several gauge couplings, we estimate the strange quark mass in the continuum limit. The perturbative one-loop mass renormalization is comparable to that for Wilson quarks and considerably smaller than that for Kogut-Susskind quarks. Also, scaling violations appear mild in comparison to other errors at present. Given their good chiral behavior and these features, domain wall quarks are attractive for evaluating the light quark masses. Our preliminary quenched result is m_s(2 GeV) = 82(15) MeV in the ${\\bar{MS}}$ scheme.

  11. Crossed-ratchet effects and domain wall geometrical pinning

    E-Print Network [OSTI]

    V. I. Marconi; A. B. Kolton; J. A. Capitan; J. A. Cuesta; A. Perez-Junquera; M. Velez; J. I. Martin; J. M. R. Parrondo

    2010-12-25T23:59:59.000Z

    The motion of a domain wall in a two dimensional medium is studied taking into account the internal elastic degrees of freedom of the wall and geometrical pinning produced both by holes and sample boundaries. This study is used to analyze the geometrical conditions needed for optimizing crossed ratchet effects in periodic rectangular arrays of asymmetric holes, recently observed experimentally in patterned ferromagnetic films. Geometrical calculations and numerical simulations have been used to obtain the anisotropic critical fields for depinning flat and kinked walls in rectangular arrays of triangles. The aim is to show with a generic elastic model for interfaces how to build a rectifier able to display crossed ratchet effects or effective potential landscapes for controlling the motion of interfaces or invasion fronts.

  12. Control of domain wall pinning by localised focused Ga?{sup +} ion irradiation on Au capped NiFe nanowires

    SciTech Connect (OSTI)

    Burn, D. M., E-mail: d.burn@imperial.ac.uk; Atkinson, D. [Department of Physics, Durham University, Durham (United Kingdom)

    2014-10-28T23:59:59.000Z

    Understanding domain wall pinning and propagation in nanowires are important for future spintronics and nanoparticle manipulation technologies. Here, the effects of microscopic local modification of the magnetic properties, induced by focused-ion-beam intermixing, in NiFe/Au bilayer nanowires on the pinning behavior of domain walls was investigated. The effects of irradiation dose and the length of the irradiated features were investigated experimentally. The results are considered in the context of detailed quasi-static micromagnetic simulations, where the ion-induced modification was represented as a local reduction of the saturation magnetization. Simulations show that domain wall pinning behavior depends on the magnitude of the magnetization change, the length of the modified region, and the domain wall structure. Comparative analysis indicates that reduced saturation magnetisation is not solely responsible for the experimentally observed pinning behavior.

  13. Melting Instantons, Domain Walls, and Large N

    E-Print Network [OSTI]

    H. B. Thacker

    2008-10-22T23:59:59.000Z

    Monte Carlo studies of $CP^{N-1}$ sigma models have shown that the structure of topological charge in these models undergoes a sharp transition at $N=N_c\\approx 4$. For $NN_c$ it is dominated by extended, thin, 1-dimensionally coherent membranes of topological charge, which can be interpreted as domain walls between discrete quasi-stable vacua. These vacua differ by a unit of background electric flux. The transition can be identified as the delocalization of topological charge, or "instanton melting," a phenomenon first suggested by Witten to resolve the conflict between instantons and large $N$ behavior. Implications for $QCD$ are discussed.

  14. Domain wall motion and electromechanical strain in lead-free piezoelectrics: Insight from the model system (1 ? x)Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}–x(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} using in situ high-energy X-ray diffraction during application of electric fields

    SciTech Connect (OSTI)

    Tutuncu, Goknur [Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611 (United States); Li, Binzhi [Department of Chemical Engineering and Materials Science, University of California, Davis, Davis, California 95616 (United States); Bowman, Keith [Illinois Institute of Technology, Armour College of Engineering, Chicago, Illinois 60616 (United States); School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Jones, Jacob L., E-mail: JacobJones@ncsu.edu [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2014-04-14T23:59:59.000Z

    The piezoelectric compositions (1 ? x)Ba(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}–x(Ba{sub 0.7}Ca{sub 0.3})TiO{sub 3} (BZT-xBCT) span a model lead-free morphotropic phase boundary (MPB) between room temperature rhombohedral and tetragonal phases at approximately x?=?0.5. In the present work, in situ X-ray diffraction measurements during electric field application are used to elucidate the origin of electromechanical strain in several compositions spanning the tetragonal compositional range 0.6???x???0.9. As BCT concentration decreases towards the MPB, the tetragonal distortion (given by c/a-1) decreases concomitantly with an increase in 90° domain wall motion. The increase in observed macroscopic strain is predominantly attributed to the increased contribution from 90° domain wall motion. The results demonstrate that domain wall motion is a significant factor in achieving high strain and piezoelectric coefficients in lead-free polycrystalline piezoelectrics.

  15. Field-driven sense elements for chirality-dependent domain wall detection and storage

    SciTech Connect (OSTI)

    Bowden, S. R. [Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Maryland Nanocenter, University of Maryland, College Park, Maryland 20742 (United States); Unguris, J. [Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

    2013-12-14T23:59:59.000Z

    A method for locally sensing and storing data of transverse domain wall chirality in planar nanowire logic and memory systems is presented. Patterned elements, in close proximity to the nanowires, respond to the asymmetry in the stray field from the domain wall to produce a chirality-dependent response. When a bias field is applied, a stray field-assisted reversal of the element magnetization results in a reversed remanent state, measurable by scanning electron microscopy with polarization analysis (SEMPA). The elements are designed as triangles with tips pointing toward the nanowire, allowing the shape anisotropy to be dominated by the base but having a portion with lower volume and lower energy barrier closest to the domain wall. Micromagnetic modeling assists in the design of the nanowire-triangle systems and experiments using SEMPA confirm the importance of aspect ratio and spacing given a constant bias field magnitude.

  16. Calculation of the strange quark mass using domain wall fermions

    E-Print Network [OSTI]

    Tom Blum; Amarjit Soni; Matthew Wingate

    2000-09-18T23:59:59.000Z

    We present a first calculation of the strange quark mass using domain wall fermions. This paper contains an overview of the domain wall discretization and a pedagogical presentation of the perturbative calculation necessary for computing the mass renormalization. We combine the latter with numerical simulations to estimate the strange quark mass. Our final result in the quenched approximation is 95(26) MeV in the ${\\bar{MS}}$ scheme at a scale of 2 GeV. We find that domain wall fermions have a small perturbative mass renormalization, similar to Wilson quarks, and exhibit good scaling behavior.

  17. Axion cosmology with long-lived domain walls

    SciTech Connect (OSTI)

    Hiramatsu, Takashi [Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Kawasaki, Masahiro; Saikawa, Ken'ichi [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa City, Chiba 277-8582 (Japan); Sekiguchi, Toyokazu, E-mail: hiramatz@yukawa.kyoto-u.ac.jp, E-mail: kawasaki@icrr.u-tokyo.ac.jp, E-mail: saikawa@icrr.u-tokyo.ac.jp, E-mail: sekiguti@a.phys.nagoya-u.ac.jp [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya City, Aichi 464-8602 (Japan)

    2013-01-01T23:59:59.000Z

    We investigate the cosmological constraints on axion models where the domain wall number is greater than one. In these models, multiple domain walls attached to strings are formed, and they survive for a long time. Their annihilation occurs due to the effects of explicit symmetry breaking term which might be raised by Planck-scale physics. We perform three-dimensional lattice simulations and compute the spectra of axions and gravitational waves produced by long-lived domain walls. Using the numerical results, we estimated relic density of axions and gravitational waves. We find that the existence of long-lived domain walls leads to the overproduction of cold dark matter axions, while the density of gravitational waves is too small to observe at the present time. Combining the results with other observational constraints, we find that the whole parameter region of models are excluded unless an unacceptable fine-tuning exists.

  18. Interface Magnetism in Multiferroics

    E-Print Network [OSTI]

    He, Qing

    2011-01-01T23:59:59.000Z

    1.2.1 Magnetism . . . . . . . . . . . . . . . . . . . 1.2.2domain walls . . . . . 3 Magnetism of domain walls in BiFeOof electrical control of magnetism in mixed phase BiFeO 3

  19. Axion-Dilaton Domain Walls and Fake Supergravity

    E-Print Network [OSTI]

    Julian Sonner; Paul K. Townsend

    2007-05-07T23:59:59.000Z

    Dynamical systems methods are used to investigate domain-wall solutions of a two-parameter family of models in which gravity is coupled to an axion, and to a dilaton with an exponential potential of either sign. A complete global analysis is presented for (i) constant axion and (ii) flat walls, including a study of bifurcations and a new exact domain-wall solution with non-constant axion. We reconsider `fake supergravity' issues in light of these results. We show, by example, how domain walls determine multi-valued superpotentials that branch at stationary points that are not stationary points of the potential, and we apply this result to potentials with anti-de Sitter vacua. We also show by example that `adapted' truncation to a single-scalar model is sometimes inconsistent, and we propose a `generalized' fake supergravity formalism that applies in some such cases.

  20. Domain Wall Formation In The Post-Inflationary Universe

    E-Print Network [OSTI]

    Z. Lalak; S. Thomas

    1993-03-12T23:59:59.000Z

    We consider the evolution of the probability distribution $\\pp (\\chi ,\\chib, \\t)$, associated with an inhomogeneous light scalar field $\\chi$ in the Robertson-Walker Universe, where the inhomogeneities are produced by quantum fluctuations during an earlier inflationary epoch. For a specific choice of scalar potential which occurs in models of so called late-time phase transitions in which domain walls are produced, $\\pp$ is shown to evolve from a Gaussian to a non-Gaussian distribution. The structure of the latter justifies the recent use of 3-dimensional percolation theory to describe the initial distribution of domain walls in these models.

  1. Observational Constraints on Varying-alpha Domain Walls

    E-Print Network [OSTI]

    P. P. Avelino; L. Sousa

    2014-06-20T23:59:59.000Z

    We consider the possibility that current hints of a spatial variation of the fine structure constant at high redshift could be due to a biased domain wall network described by a scalar field non-minimally coupled to the electromagnetic field. We show that in order to be cause of the reported spatial variation of the fine structure constant without being in conflict with the observed anisotropies of the cosmic microwave background, the characteristic scale of the network would have to be of the order of the Hubble radius and the fractional contribution of the domain wall network to the energy density of the Universe would need to be in the range $10^{-10} temperature distribution of the cosmic microwave background detected by Planck and WMAP and provide a significant contribution to the excess B-mode polarisation power detected by BICEP2. Since the domain wall contribution to the cosmic energy budget only becomes important at late times, domain wall networks cannot play a significant role as a seed for large scale structure formation and primary cosmic microwave background anisotropies.

  2. Vector dark domain wall solitons in a fiber ring laser

    E-Print Network [OSTI]

    H. Zhang; D. Y. Tang; L. M. Zhao; R. J. Knize

    2009-10-15T23:59:59.000Z

    We observe a novel type of vector dark soliton in a fiber ring laser. The vector dark soliton consists of stable localized structures separating the two orthogonal linear polarization eigenstates of the laser emission and is visible only when the total laser emission is measured. Moreover, polarization domain splitting and moving polarization domain walls (PDWs) were also experimentally observed.

  3. Optimized cobalt nanowires for domain wall manipulation imaged by in situ Lorentz microscopy

    SciTech Connect (OSTI)

    Rodriguez, L. A. [Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, 50018 Zaragoza (Spain) [Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, 50018 Zaragoza (Spain); Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza (Spain); Transpyrenean Associated Laboratory for Electron Microscopy (TALEM), CEMES-INA, CNRS-Universidad de Zaragoza, Toulouse (France); CEMES-CNRS 29, rue Jeanne Marvig, B.P. 94347 F-31055, Toulouse Cedex (France); Magen, C. [Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, 50018 Zaragoza (Spain) [Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, 50018 Zaragoza (Spain); Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza (Spain); Transpyrenean Associated Laboratory for Electron Microscopy (TALEM), CEMES-INA, CNRS-Universidad de Zaragoza, Toulouse (France); Fundacion ARAID, 50004 Zaragoza (Spain)] [Spain; Snoeck, E.; Gatel, C. [Transpyrenean Associated Laboratory for Electron Microscopy (TALEM), CEMES-INA, CNRS-Universidad de Zaragoza, Toulouse (France) [Transpyrenean Associated Laboratory for Electron Microscopy (TALEM), CEMES-INA, CNRS-Universidad de Zaragoza, Toulouse (France); CEMES-CNRS 29, rue Jeanne Marvig, B.P. 94347 F-31055, Toulouse Cedex (France); Serrano-Ramon, L. [Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza (Spain) [Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza (Spain); Instituto de Ciencia de Materiales de Aragon (ICMA), Universidad de Zaragoza-CSIC, 50009 Zaragoza (Spain); and others

    2013-01-14T23:59:59.000Z

    Direct observation of domain wall (DW) nucleation and propagation in focused electron beam induced deposited Co nanowires as a function of their dimensions was carried out by Lorentz microscopy (LTEM) upon in situ application of magnetic field. Optimal dimensions favoring the unambiguous DW nucleation/propagation required for applications were found in 500-nm-wide and 13-nm-thick Co nanowires, with a maximum nucleation field and the largest gap between nucleation and propagation fields. The internal DW structures were resolved using the transport-of-intensity equation formalism in LTEM images and showed that the optimal nanowire dimensions correspond to the crossover between the nucleation of transverse and vortex walls.

  4. In situ Lorentz TEM magnetization studies on a Fe-Pd-Co martensitic alloy.

    SciTech Connect (OSTI)

    Budruk, A.; Phatak, C.; Petford-Long, A. K.; De Graef, M. (Center for Nanoscale Materials); ( MSD); (Carnegie Mellon Univ.)

    2011-08-01T23:59:59.000Z

    Understanding domain wall pinning centers and the resultant mobility of ferroic (ferromagnetic and ferroelastic) walls under an applied magnetic field is of central importance to actuator applications of magnetic shape memory alloys. The movement of ferroic boundaries in a twinned Fe-Pd-Co martensite was analyzed by means of Lorentz mode transmission electron microscopy. An in situ magnetizing sample-holder was used to record the evolution of the magnetic domain structure as a function of the applied field. Fresnel images were recorded at different field values and a phase reconstruction algorithm was used to map the magnetization configuration inside the foil. The motion of magnetic domain walls was found to be strongly influenced by the presence of twin boundaries. Free-standing domain walls became mobile at fields as low as 15 Oe, whereas an order of magnitude higher field was required to depin domain walls that coincided with twin boundaries. The domain wall motion was completely reversible with a notable hysteresis.

  5. Simulations of magnetic nanoparticle Brownian motion

    E-Print Network [OSTI]

    Daniel B Reeves; John B Weaver

    2014-03-25T23:59:59.000Z

    Magnetic nanoparticles are useful in many medical applications because they interact with biology on a cellular level thus allowing microenvironmental investigation. An enhanced understanding of the dynamics of magnetic particles may lead to advances in imaging directly in magnetic particle imaging (MPI) or through enhanced MRI contrast and is essential for nanoparticle sensing as in magnetic spectroscopy of Brownian motion (MSB). Moreover, therapeutic techniques like hyperthermia require information about particle dynamics for effective, safe, and reliable use in the clinic. To that end, we have developed and validated a stochastic dynamical model of rotating Brownian nanoparticles from a Langevin equation approach. With no field, the relaxation time toward equilibrium matches Einstein's model of Brownian motion. In a static field, the equilibrium magnetization agrees with the Langevin function. For high frequency or low amplitude driving fields, behavior characteristic of the linearized Debye approximation is reproduced. In a higher field regime where magnetic saturation occurs, the magnetization and its harmonics compare well with the effective field model. On another level, the model has been benchmarked against experimental results, successfully demonstrating that harmonics of the magnetization carry enough information to infer environmental parameters like viscosity and temperature.

  6. New confining force solution of QCD axion domain wall problem

    E-Print Network [OSTI]

    S. M. Barr; Jihn E. Kim

    2014-11-13T23:59:59.000Z

    The serious cosmological problems created by the axion-string/axion-domain-wall system in standard axion models are alleviated by positing the existence of a new confining force. The instantons of this force can generate an axion potential that erases the axion strings long before QCD effects become important, thus preventing QCD-generated axion walls from ever appearing. Axion walls generated by the new confining force would decay so early as not to contribute significantly to the energy in axion dark matter.

  7. Proton decay matrix elements with domain-wall fermions

    E-Print Network [OSTI]

    Y. Aoki; C. Dawson; J. Noaki; A. Soni

    2006-09-18T23:59:59.000Z

    Hadronic matrix elements of operators relevant to nucleon decay in grand unified theories are calculated numerically using lattice QCD. In this context, the domain-wall fermion formulation, combined with non-perturbative renormalization, is used for the first time. These techniques bring reduction of a large fraction of the systematic error from the finite lattice spacing. Our main effort is devoted to a calculation performed in the quenched approximation, where the direct calculation of the nucleon to pseudoscalar matrix elements, as well as the indirect estimate of them from the nucleon to vacuum matrix elements, are performed. First results, using two flavors of dynamical domain-wall quarks for the nucleon to vacuum matrix elements are also presented to address the systematic error of quenching, which appears to be small compared to the other errors. Our results suggest that the representative value for the low energy constants from the nucleon to vacuum matrix elements are given as |alpha| simeq |beta| simeq 0.01 GeV^3. For a more reliable estimate of the physical low energy matrix elements, it is better to use the relevant form factors calculated in the direct method. The direct method tends to give smaller value of the form factors, compared to the indirect one, thus enhancing the proton life-time; indeed for the pi^0 final state the difference between the two methods is quite appreciable.

  8. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  9. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  10. Stochastic Domain-Wall Depinning in Magnetic Nanowires

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  11. Time-resolved observation of fast domain-walls driven by vertical spin currents in short tracks

    SciTech Connect (OSTI)

    Sampaio, Joao; Lequeux, Steven; Chanthbouala, Andre; Cros, Vincent; Grollier, Julie [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France)] [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); Metaxas, Peter J. [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France) [Unité Mixte de Physique CNRS/Thales and Université Paris-Sud 11, 1 Ave. A. Fresnel, 91767 Palaiseau (France); School of Physics, M013, University of Western Australia, 35 Stirling Highway, Crawley WA 6009 (Australia); Matsumoto, Rie; Yakushiji, Kay; Kubota, Hitoshi; Fukushima, Akio; Yuasa, Shinji [National Institute of Advanced Industrial Science and Technology (AIST) 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)] [National Institute of Advanced Industrial Science and Technology (AIST) 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Nishimura, Kazumasa; Nagamine, Yoshinori; Maehara, Hiroki; Tsunekawa, Koji [Process Development Center, Canon ANELVA Corporation, Kurigi 2-5-1, Asao, Kawasaki, Kanagawa 215-8550 (Japan)] [Process Development Center, Canon ANELVA Corporation, Kurigi 2-5-1, Asao, Kawasaki, Kanagawa 215-8550 (Japan)

    2013-12-09T23:59:59.000Z

    We present time-resolved measurements of the displacement of magnetic domain-walls (DWs) driven by vertical spin-polarized currents in track-shaped magnetic tunnel junctions. In these structures, we observe very high DW velocities (600?m/s) at current densities below 10{sup 7}?A/cm{sup 2}. We show that the efficient spin-transfer torque combined with a short propagation distance allows avoiding the Walker breakdown process and achieving deterministic, reversible, and fast (?1?ns) DW-mediated switching of magnetic tunnel junction elements, which is of great interest for the implementation of fast DW-based spintronic devices.

  12. Evolution of string-wall networks and axionic domain wall problem

    SciTech Connect (OSTI)

    Hiramatsu, Takashi [Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Kawasaki, Masahiro; Saikawa, Ken'ichi, E-mail: hiramatz@yukawa.kyoto-u.ac.jp, E-mail: kawasaki@icrr.u-tokyo.ac.jp, E-mail: saikawa@icrr.u-tokyo.ac.jp [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa City, Chiba 277-8582 (Japan)

    2011-08-01T23:59:59.000Z

    We study the cosmological evolution of domain walls bounded by strings which arise naturally in axion models. If we introduce a bias in the potential, walls become metastable and finally disappear. We perform two dimensional lattice simulations of domain wall networks and estimate the decay rate of domain walls. By using the numerical results, we give a constraint for the bias parameter and the Peccei-Quinn scale. We also discuss the possibility to probe axion models by direct detection of gravitational waves produced by domain walls.

  13. Investigation of dominant spin wave modes by domain walls collision

    SciTech Connect (OSTI)

    Ramu, M.; Purnama, I.; Goolaup, S.; Chandra Sekhar, M.; Lew, W. S., E-mail: wensiang@ntu.edu.sg [School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

    2014-06-28T23:59:59.000Z

    Spin wave emission due to field-driven domain wall (DW) collision has been investigated numerically and analytically in permalloy nanowires. The spin wave modes generated are diagonally symmetric with respect to the collision point. The non-propagating mode has the highest amplitude along the middle of the width. The frequency of this mode is strongly correlated to the nanowire geometrical dimensions and is independent of the strength of applied field within the range of 0.1?mT to 1?mT. For nanowire with film thickness below 5?nm, a second spin wave harmonic mode is observed. The decay coefficient of the spin wave power suggests that the DWs in a memory device should be at least 300?nm apart for them to be free of interference from the spin waves.

  14. Neutron irradiation effects on domain wall mobility and reversibility in lead zirconate titanate thin films

    E-Print Network [OSTI]

    Ferreira, Paulo J.

    changes.1 Damage accumulates when fast neutrons undergo scattering collisions with atomic nuclei resultingNeutron irradiation effects on domain wall mobility and reversibility in lead zirconate titanate://scitation.aip.org/termsconditions. Downloaded to ] IP: 146.6.84.63 On: Wed, 23 Oct 2013 17:34:29 #12;Neutron irradiation effects on domain wall

  15. Energy-momentum balance in particle - domain wall perforating collision

    E-Print Network [OSTI]

    D. V. Gal'tsov; E. Yu. Melkumova; P. A. Spirin

    2015-02-10T23:59:59.000Z

    We investigate the energy-momentum balance in the perforating collision of a point particle with an infinitely thin planar domain wall within the linearized gravity in arbitrary dimensions. Since the metric of the wall increases with distance, the wall and the particle are never free, and their energy-momentum balance involves not only the instantaneous kinetic momenta, but also the non-local contribution of gravitational stresses. However, careful analysis shows that the stresses can be unambiguously divided between the colliding objects leading to definition of the gravitationally dressed momenta. These take into account for gravity in the same way as the potential energy does in the non-relativistic theory, but our treatment is fully relativistic. Another unusual feature of our problem is the non-vanishing flux of the total energy-momentum tensor through the lateral surface of the world tube. In this case the zero divergence of the energy-momentum tensor does not imply conservation of the total momentum defined as the integral over the space-like section of the tube. But one can still define the conservation low infinitesimally, passing to time derivatives of the momenta. Using this definition we establish the momentum balance in terms of the dressed particle and wall momenta.

  16. Quantum Fusion of Strings (Flux Tubes) and Domain Walls

    E-Print Network [OSTI]

    S. Bolognesi; M. Shifman; M. B. Voloshin

    2009-05-20T23:59:59.000Z

    We consider formation of composite strings and domain walls as a result of fusion of two elementary objects (elementary strings in the first case and elementary walls in the second) located at a distance from each other. The tension of the composite object T_2 is assumed to be less than twice the tension of the elementary object T_1, so that bound states are possible. If in the initial state the distance d between the fusing strings or walls is much larger than their thickness and satisfies the conditions T_1 d^2 >> 1 (in the string case) and T_1 d^3 >> 1 (in the wall case), the problem can be fully solved quasiclassically. The fusion probability is determined by the first, "under the barrier" stage of the process. We find the bounce configuration and its extremal action S_B. In the wall problem e^{-S_B} gives the fusion probability per unit time per unit area. In the string case, due to a logarithmic infrared divergence, the problem is well formulated only for finite-length strings. The fusion probability per unit time can be found in the limit in which the string length is much larger than the distance between two merging strings.

  17. Persistent conductive footprints of 109° domain walls in bismuth ferrite films

    SciTech Connect (OSTI)

    Stolichnov, I.; Iwanowska, M.; Colla, E.; Setter, N. [Ceramics Laboratory, EPFL-Swiss Federal Institute of Technology, Lausanne 1015 (Switzerland); Ziegler, B.; Gaponenko, I.; Paruch, P. [DPMC-MaNEP, University of Geneva, 24 Quai Ernest Ansermet, 1211 Geneva 4 (Switzerland); Huijben, M.; Rijnders, G. [Faculty of Science and Technology and MESA Institute for Nanotechnology, University of Twente, 7500 AE Enschede (Netherlands)

    2014-03-31T23:59:59.000Z

    Using conductive and piezoforce microscopy, we reveal a complex picture of electronic transport at weakly conductive 109° domain walls in bismuth ferrite films. Even once initial ferroelectric stripe domains are changed/erased, persistent conductive paths signal the original domain wall position. The conduction at such domain wall “footprints” is activated by domain movement and decays rapidly with time, but can be re-activated by opposite polarity voltage. The observed phenomena represent true leakage conduction rather than merely displacement currents. We propose a scenario of hopping transport in combination with thermionic injection over interfacial barriers controlled by the ferroelectric polarization.

  18. Time Evolution of Temperature and Entropy of Various Collapsing Domain Walls

    E-Print Network [OSTI]

    Evan Halstead

    2012-09-10T23:59:59.000Z

    We investigate the time evolution of the temperature and entropy of gravitationally collapsing domain walls as seen by an asymptotic observer. In particular, we seek to understand how topology and the addition of a cosmological constant affect the gravitational collapse. Previous work has shown that the entropy of a spherically symmetric collapsing domain approaches a constant. In this paper, we reproduce these results, using both a fully quantum and a semi-classical approach, then we repeat the process for a de Sitter Schwarzschild domain wall (spherical with cosmological constant) and a (3+1) BTZ domain wall (cylindrical). We do this by coupling a scalar field to the background of the domain wall and analyzing the spectrum of radiation as a function of time. We find that the spectrum is quasi-thermal, with the degree of thermality increasing as the domain wall approaches the horizon. The thermal distribution allows for the determination of the temperature as a function of time, and we find that the late time temperature is very close to the Hawking temperature and that it also exhibits the proper scaling with the mass. From the temperature we find the entropy. Since the collapsing domain wall is what forms a black hole, we can compare the results to those of the standard entropy-area relation. We find that the entropy does in fact approach a constant that is close to the Hawking entropy. However, both the de Sitter Schwarzschild domain wall and the (3+1) BTZ domain wall show periods of decreasing entropy, which suggests that spontaneous collapse may be prevented.

  19. Domain wall solitons and Hopf algebraic translational symmetries in noncommutative field theories

    SciTech Connect (OSTI)

    Sasai, Yuya; Sasakura, Naoki [Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)

    2008-02-15T23:59:59.000Z

    Domain wall solitons are the simplest topological objects in field theories. The conventional translational symmetry in a field theory is the generator of a one-parameter family of domain wall solutions, and induces a massless moduli field which propagates along a domain wall. We study similar issues in braided noncommutative field theories possessing Hopf algebraic translational symmetries. As a concrete example, we discuss a domain wall soliton in the scalar {phi}{sup 4} braided noncommutative field theory in Lie-algebraic noncommutative space-time, [x{sup i},x{sup j}]=2i{kappa}{epsilon}{sup ijk}x{sub k} (i,j,k=1,2,3), which has a Hopf algebraic translational symmetry. We first discuss the existence of a domain wall soliton in view of Derrick's theorem, and construct explicitly a one-parameter family of solutions in perturbation of the noncommutativity parameter {kappa}. We then find the massless moduli field which propagates on the domain wall soliton. We further extend our analysis to the general Hopf algebraic translational symmetry.

  20. Current induced perpendicular-magnetic-anisotropy racetrack memory with magnetic field assistance

    SciTech Connect (OSTI)

    Zhang, Y.; Klein, J.-O.; Chappert, C.; Ravelosona, D. [IEF, University of Paris-Sud, Orsay 91405 (France); UMR8622, CNRS, Orsay 91405 (France); Zhao, W. S., E-mail: weisheng.zhao@u-psud.fr [IEF, University of Paris-Sud, Orsay 91405 (France); UMR8622, CNRS, Orsay 91405 (France); Electronics and Information Engineering School, University of Beihang, Beijing 100191 (China)

    2014-01-20T23:59:59.000Z

    High current density is indispensable to shift domain walls (DWs) in magnetic nanowires, which limits the using of racetrack memory (RM) for low power and high density purposes. In this paper, we present perpendicular-magnetic-anisotropy (PMA) Co/Ni RM with global magnetic field assistance, which lowers the current density for DW motion. By using a compact model of PMA RM and 40?nm design kit, we perform mixed simulation to validate the functionality of this structure and analyze its density potential. Stochastic DW motion behavior has been taken into account and statistical Monte-Carlo simulations are carried out to evaluate its reliability performance.

  1. Substrate Clamping Effects on Irreversible Domain Wall Dynamics in Lead Zirconate Titanate Thin Films

    SciTech Connect (OSTI)

    Griggio, Flavio [ORNL; Jesse, Stephen [ORNL; Kumar, Amit [ORNL; Ovchinnikov, Oleg S [ORNL; Kim, H. [Pennsylvania State University, University Park, PA; Jackson, T. N. [Pennsylvania State University, University Park, PA; Damjanovic, Dragan [ORNL; Kalinin, Sergei V [ORNL; Trolier-Mckinstry, Susan E [ORNL

    2012-01-01T23:59:59.000Z

    The role of long-range strain interactions on domain wall dynamics is explored through macroscopic and local measurements of nonlinear behavior in mechanically clamped and released polycrystalline lead zirconate-titanate (PZT) films. Released films show a dramatic change in the global dielectric nonlinearity and its frequency dependence as a function of mechanical clamping. Furthermore, we observe a transition from strong clustering of the nonlinear response for the clamped case to almost uniform nonlinearity for the released film. This behavior is ascribed to increased mobility of domain walls. These results suggest the dominant role of collective strain interactions mediated by the local and global mechanical boundary conditions on the domain wall dynamics. The work presented in this Letter demonstrates that measurements on clamped films may considerably underestimate the piezoelectric coefficients and coupling constants of released structures used in microelectromechanical systems, energy harvesting systems, and microrobots.

  2. Analytical and micromagnetic study of a Neel domain wall

    E-Print Network [OSTI]

    Rivkin, K.; Romanov, K.; Abanov, Artem; Adamov, Y.; Saslow, W. M.

    2008-01-01T23:59:59.000Z

    ; =Mx#1;x#2; /Ms and v#1;x#2;=My#1;x#2; /Ms, with u#1;x#2;2+v#1;x#2;2=1. To obtain the magnetization distribution one minimizes the magnetostatic energy functional with the boundary con- ditions v#1;#3;#4;#2;= #3;1, u#1;0#2;=1. The first condition... uniformly magnetized magnetic prism that is infinite in the y direction and averaged along the x-z plane, is given by17 #11; #14; 1 ? p 2 2p ln#1;1 + p2#2; + p ln p + 2 arctan#8;1p p = h2w . #1;3.1#2; Assuming that h#5;w, i.e., the sample is thin, we...

  3. Analysis of ultra-narrow ferromagnetic domain walls

    SciTech Connect (OSTI)

    Jenkins, Catherine; Paul, David

    2012-01-10T23:59:59.000Z

    New materials with high magnetic anisotropy will have domains separated by ultra-narrow ferromagnetic walls with widths on the order of a few unit cells, approaching the limit where the elastic continuum approximation often used in micromagnetic simulations is accurate. The limits of this approximation are explored, and the static and dynamic interactions with intrinsic crystalline defects and external driving #12;elds are modeled. The results developed here will be important when considering the stability of ultra-high-density storage media.

  4. ccsd-00000514(version1):22Jul2003 Electronic transport through domain walls in ferromagnetic nanowires

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Department of Physics, University of Western Australia, Nedlands WA 6907, Australia We study the effect in these channels become coupled. For very short domain walls or at high longitudinal kinetic energy, this coupling longitudinal energy are transmitted adiabatically while the electrons at high longitudinal energy

  5. Thermoelectric Effect across the Metal-Insulator Domain Walls in VO2

    E-Print Network [OSTI]

    Wu, Junqiao

    Thermoelectric Effect across the Metal-Insulator Domain Walls in VO2 Microbeams J. Cao,,, W. Fan-performance thermoelectric materials are currently one of the focuses in materials research for energy conversion technologies.1-4 A good thermoelectric material should have a relatively high thermopower (Seebeck coefficient

  6. Localized Fermions on Superconducting Domain Walls and Extended Supersymmetry with non-trivial Topological Charges

    E-Print Network [OSTI]

    V. K. Oikonomou

    2014-06-05T23:59:59.000Z

    In this letter we demonstrate that the fermionic zero modes on a superconducting domain wall can be associated to an one dimensional $N=6$ supersymmetry that contains non-trivial topological charges. In addition, the system also possesses three distinct $N=4$ supersymmetries with non-trivial topological charges and we also study some duality transformations of the supersymmetric algebras.

  7. Localization and chiral symmetry in 2+1 flavor domain wall QCD

    SciTech Connect (OSTI)

    David J. Antonio; Kenneth C. Bowler; Peter A. Boyle; Norman H. Christ; Michael A. Clark; Saul D. Cohen; Chris Dawson; Alistair Hart; Balint Joó; Chulwoo Jung; Richard D. Kenway; Shu Li; Meifeng Lin; Robert D. Mawhinney; Christopher M. Maynard; Shigemi Ohta; Robert J. Tweedie; Azusa Yamaguchi

    2008-01-01T23:59:59.000Z

    We present results for the dependence of the residual mass of domain wall fermions (DWF) on the size of the fifth dimension and its relation to the density and localization properties of low-lying eigenvectors of the corresponding hermitian Wilson Dirac operator relevant to simulations of 2+1 flavor domain wall QCD. Using the DBW2 and Iwasaki gauge actions, we generate ensembles of configurations with a $16^3\\times 32$ space-time volume and an extent of 8 in the fifth dimension for the sea quarks. We demonstrate the existence of a regime where the degree of locality, the size of chiral symmetry breaking and the rate of topology change can be acceptable for inverse lattice spacings $a^{-1} \\ge 1.6$ GeV.

  8. Perturbative renormalization of the first moment of structure functions for domain-wall QCD

    SciTech Connect (OSTI)

    Capitani, Stefano [Institut fuer Physik, FB Theoretische Physik, Universitaet Graz, A-8010 Graz (Austria)

    2006-01-01T23:59:59.000Z

    Using the domain-wall formulation of lattice fermions, we have computed the one-loop renormalization factors of one-link operators which measure the first nontrivial moment of the unpolarized, polarized, and transversity structure functions, in the flavor nonsinglet sector. The knowledge of these factors is necessary in order to extract physical numbers from domain-wall Monte Carlo simulations of parton distributions. We have automated the perturbative calculations by developing suitable FORM codes. The results show that in many instances the total renormalization factors are almost equal to one, and that hence the corresponding operators are, for the appropriate values of the Dirac mass M and the coupling g{sub 0}, practically unrenormalized.

  9. Quantum Decay of the 'False Vacuum' and Pair Creation of Soliton Domain Walls

    SciTech Connect (OSTI)

    Miller, John H. Jr. [Department of Physics and Texas Center for Superconductivity, University of Houston, 4800 Calhoun Road, Houston, Texas 77204-5005 (United States)

    2011-03-28T23:59:59.000Z

    Quantum decay of metastable states ('false vacua') has been proposed as a mechanism for bubble nucleation of new universes and phase transitions in the early universe. Experiments indicate the occurrence of false vacuum decay, within a region bounded by soliton domain walls that nucleate via quantum tunneling, in a highly anisotropic condensed matter system. This phenomenon provides a compelling example of false vacuum decay in the laboratory.

  10. PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ENTITLED - DOMAIN WALL FERMIONS AT TEN YEARS (VOLUME 84)

    SciTech Connect (OSTI)

    BLUM,T.; SONI,A.

    2007-03-15T23:59:59.000Z

    The workshop was held to mark the 10th anniversary of the first numerical simulations of QCD using domain wall fermions initiated at BNL. It is very gratifying that in the intervening decade widespread use of domain wall and overlap fermions is being made. It therefore seemed appropriate at this stage for some ''communal introspection'' of the progress that has been made, hurdles that need to be overcome, and physics that can and should be done with chiral fermions. The meeting was very well attended, drawing about 60 registered participants primarily from Europe, Japan and the US. It was quite remarkable that pioneers David Kaplan, Herbert Neuberger, Rajamani Narayanan, Yigal Shamir, Sinya Aoki, and Pavlos Vranas all attended the workshop. Comparisons between domain wall and overlap formulations, with their respective advantages and limitations, were discussed at length, and a broad physics program including pion and kaon physics, the epsilon regime, nucleon structure, and topology, among others, emerged. New machines and improved algorithms have played a key role in realizing realistic dynamical fermion lattice simulations (small quark mass, large volume, and so on), so much in fact that measurements are now as costly. Consequently, ways to make the measurements more efficient were also discussed. We were very pleased to see the keen and ever growing interest in chiral fermions in our community and the significant strides our colleagues have made in bringing chiral fermions to the fore of lattice QCD calculations. Their contributions made the workshop a success, and we thank them deeply for sharing their time and ideas. Finally, we must especially acknowledge Norman Christ and Bob Mawhinney for their early and continued collaboration without which the success of domain wall fermions would not have been possible.

  11. The Aichelburg-Sexl Boost of Domain-Walls and Cosmic Strings

    E-Print Network [OSTI]

    C. Barrabes; P. A. Hogan; W. Israel

    2002-06-07T23:59:59.000Z

    We consider the application of the Aichelburg-Sexl boost to plane and line distributions of matter. Our analysis shows that for a domain wall the space-time after the boost is flat except on a null hypersurface which is the history of a null shell. For a cosmic string we study the influence of the boost on the conical singularity and give the new value of the conical deficit.

  12. Domain wall fermion calculation of nucleon g_A/g_V

    E-Print Network [OSTI]

    Tom Blum; Shigemi Ohta; Shoichi Sasaki

    2000-11-01T23:59:59.000Z

    We present a preliminary domain-wall fermion lattice-QCD calculation of isovector vector and axial charges, g_V and g_A, of the nucleon. Since the lattice renormalizations, Z_V and Z_A, of the currents are identical with DWF, the lattice ratio (g_A/g_V)^{lattice} directly yields the continuum value. Indeed Z_V determined from the matrix element of the vector current agrees closely with Z_A from a non-perturbative renormalization study of quark bilinears. We also obtain spin related quantities Delta-q/g_V and delta-q/g_V.

  13. Phase ordering percolation and domain-wall survival in segregating binary Bose-Einstein condensates

    E-Print Network [OSTI]

    Takeuchi, Hiromitsu; Dehara, Kentaro

    2015-01-01T23:59:59.000Z

    Percolation theory is applied to the phase transition dynamics of domain pattern formation in segregating quasi-two-dimensional binary Bose--Einstein condensates. Our numerical experiments revealed that the percolation threshold is close to 0.5. A long-range open domain wall appears with a fractal dimension between two percolating domains. Such a wall can survive for a long time as a relic of the phase transition according to the dynamic finite-size-scaling hypothesis, which seems to be in contrast to the current understanding in cosmology that an infinite defect violates a scale invariance.

  14. Nucleon axial charge from quenched lattice QCD with domain wall fermions

    E-Print Network [OSTI]

    Shoichi Sasaki; Kostas Orginos; Shigemi Ohta; Tom Blum; for the RBCK Collaboration

    2003-07-18T23:59:59.000Z

    We present a quenched lattice calculation of the nucleon isovector vector and axial-vector charges gV and gA. The chiral symmetry of domain wall fermions makes the calculation of the nucleon axial charge particularly easy since the Ward-Takahashi identity requires the vector and axial-vector currents to have the same renormalization, up to lattice spacing errors of order O(a^2). The DBW2 gauge action provides enhancement of the good chiral symmetry properties of domain wall fermions at larger lattice spacing than the conventional Wilson gauge action. Taking advantage of these methods and performing a high statistics simulation, we find a significant finite volume effect between the nucleon axial charges calculated on lattices with (1.2 fm)^3 and (2.4 fm)^3 volumes (with lattice spacing, a, of about 0.15 fm). On the large volume we find gA = 1.212 +/- 0.027(statistical error) +/- 0.024(normalization error). The quoted systematic error is the dominant (known) one, corresponding to current renormalization. We discuss other possible remaining sources of error. This theoretical first principles calculation, which does not yet include isospin breaking effects, yields a value of gA only a little bit below the experimental one, 1.2670 +/- 0.0030.

  15. Domain Walls and Anchoring Transitions Mimicking Nematic Biaxiality in the Oxadiazole Bent-Core Liquid Crystal C7

    E-Print Network [OSTI]

    Kim, Young-ki; Xiang, Jie; Shin, Sung-Tae; Lavrentovich, Oleg D

    2015-01-01T23:59:59.000Z

    We investigate the origin of secondary disclinations that were recently described as a new evidence of a biaxial nematic phase in an oxadiazole bent-core thermotropic liquid crystal C7. With an assortment of optical techniques such as polarizing optical microscopy, LC PolScope, and fluorescence confocal polarizing microscopy, we demonstrate that the secondary disclinations represent non-singular domain walls formed in an uniaxial nematic during the surface anchoring transition, in which surface orientation of the director changes from tangential (parallel to the bounding plates) to tilted. Each domain wall separates two regions with the director tilted in opposite azimuthal directions. At the centre of the wall, the director remains parallel to the bonding plates. The domain walls can be easily removed by applying a modest electric field. The anchoring transition is explained by the balance of (a) the intrinsic perpendicular surface anchoring produced by the polyimide aligning layer and (b) tangential alignme...

  16. BiFeO3 Domain Wall Energies and Structures: A Combined Experimental and Density Functional Theory+U Study

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, Yi; Nelson, Chris; Melville, Alexander; Winchester, Benjamin; Shang, Shunli; Liu, Zi-Kui; Schlom, Darrell G.; Pan, Xiaoqing; Chen, Long-Qing

    2013-06-01T23:59:59.000Z

    We determined the atomic structures and energies of 109°, 180°, and 71° domain walls in BiFeO3, combining density functional theory+U calculations and aberration-corrected transmission electron microscopy images. We find a substantial Bi sublattice shift and a rather uniform Fe sublattice across the walls. The calculated wall energies (?) follow the sequence ?109 180 71 for the 109°, 180°, and 71° walls. We attribute the high 71° wall energy to an opposite tilting rotation of the oxygen octahedra and the low 109° wall energy to the opposite twisting rotation of the oxygen octahedra across the domain walls.

  17. Nucleon form factors with 2+1 flavor dynamical domain-wall fermions

    E-Print Network [OSTI]

    Takeshi Yamazaki; Yasumichi Aoki; Tom Blum; Huey-Wen Lin; Shigemi Ohta; Shoichi Sasaki; Robert Tweedie; James Zanotti

    2009-04-14T23:59:59.000Z

    We report our numerical lattice QCD calculations of the isovector nucleon form factors for the vector and axialvector currents: the vector, induced tensor, axialvector, and induced pseudoscalar form factors. The calculation is carried out with the gauge configurations generated with N_f=2+1 dynamical domain wall fermions and Iwasaki gauge actions at beta = 2.13, corresponding to a cutoff 1/a = 1.73 GeV, and a spatial volume of (2.7 fm)^3. The up and down quark masses are varied so the pion mass lies between 0.33 and 0.67 GeV while the strange quark mass is about 12% heavier than the physical one. We calculate the form factors in the range of momentum transfers, 0.2 6 is required to ensure that finite volume effects are below 1%.

  18. Direct Observation of Nanoscale Peltier and Joule Effects at Metal-Insulator Domain Walls in Vanadium Dioxide Nanobeams

    E-Print Network [OSTI]

    Wu, Junqiao

    Direct Observation of Nanoscale Peltier and Joule Effects at Metal- Insulator Domain Walls localized alternating Peltier heating and cooling as well as Joule heating concentrated at the M-I domain the monoclinic phase identification. KEYWORDS: Vanadium dioxide, thermoreflectance microscopy, Peltier effect

  19. Magnetic domain walls for on-chip transport and detection of superparamagnetic beads

    E-Print Network [OSTI]

    Rapoport, Elizabeth Ashera

    2014-01-01T23:59:59.000Z

    Surface-functionalized superparamagnetic (SPM) microbeads are of great interest in biomedical research and diagnostic device engineering for tagging, manipulating, and detecting chemical and biological species in a fluid ...

  20. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP »summerlectures

  1. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP »summerlecturesVortices Influence of

  2. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm)HydrogenRFP »summerlecturesVortices Influence

  3. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link to facebookInfiniband cables

  4. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link to facebookInfiniband cablesVortices

  5. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link to facebookInfiniband

  6. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link to facebookInfinibandVortices Influence

  7. Influence of Domain Wall Pinning on the Dynamic Behavior of Magnetic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn Other News link to facebookInfinibandVortices

  8. Real-Time Magnetic Field Pitch Angle Estimation with a Motional Stark Effect Diagnostic Using Kalman Filtering

    E-Print Network [OSTI]

    Real-Time Magnetic Field Pitch Angle Estimation with a Motional Stark Effect Diagnostic Using Kalman Filtering

  9. The finite temperature QCD using 2+1 flavors of domain wall fermions at Nt = 8

    SciTech Connect (OSTI)

    Cheng, M; Christ, N H; Li, M; Mawhinney, R D; Renfrew, D; Hegde, P; Karsch, F; Lin, M; Vranas, P

    2009-11-30T23:59:59.000Z

    We study the region of the QCD phase transition using 2+1 flavors of domain wall fermions (DWF) and a 16{sup 3} x 8 lattice volume with a fifth dimension of L{sub s} = 32. The disconnected light quark chiral susceptibility, quark number susceptibility and the Polyakov loop suggest a chiral and deconfining crossover transition lying between 155 and 185 MeV for our choice of quark mass and lattice spacing. In this region the lattice scale deduced from the Sommer parameter r{sub 0} is a{sup -1} {approx} 1.3 GeV, the pion mass is {approx} 300 MeV and the kaon mass is approximately physical. The peak in the chiral susceptibility implies a pseudo critical temperature T{sub c} = 171(10)(17) MeV where the first error is associated with determining the peak location and the second with our unphysical light quark mass and non-zero lattice spacing. The effects of residual chiral symmetry breaking on the chiral condensate and disconnected chiral susceptibility are studied using several values of the valence L{sub s}.

  10. Finite Temperature QCD Using 2 þ 1 Flavors of Domain Wall Fermions at Nt ¼ 8

    SciTech Connect (OSTI)

    Karsch, F.; Lim, M; Cheng, M; Christ, N; Hegde, P.; Li, L.; Mawhinney, R.; Renfrew, D.; Vranas, P.

    2010-03-30T23:59:59.000Z

    We study the region of the QCD phase transition using 2 + 1 flavors of domain wall fermions and a 16{sup 3} x 8 lattice volume with a fifth dimension of L{sub s} = 32. The disconnected light quark chiral susceptibility, quark number susceptibility, and the Polyakov loop suggest a chiral and deconfining crossover transition lying between 155 and 185 MeV for our choice of quark mass and lattice spacing. In this region the lattice scale deduced from the Sommer parameter r{sub 0} is a{sup -1} {approx} 1.3 GeV, the pion mass is {approx} 300 MeV, and the kaon mass is approximately physical. The peak in the chiral susceptibility implies a pseudocritical temperature T{sub c} = 171(10)(17) MeV where the first error is associated with determining the peak location and the second with our unphysical light quark mass and nonzero lattice spacing. The effects of residual chiral symmetry breaking on the chiral condensate and disconnected chiral susceptibility are studied using several values of the valence L{sub s}.

  11. Domain Walls, near-BPS Bubbles and Probabilities in the Landscape

    SciTech Connect (OSTI)

    Ceresole, Anna; /INFN, Turin /Turin U.; Dall'Agata, Gianguido; /CERN; Giryavets, Alexander; Kallosh, Renata; Linde, Andrei; /Stanford U., Phys. Dept.

    2006-06-27T23:59:59.000Z

    We develop a theory of static BPS domain walls in stringy landscape and present a large family of BPS walls interpolating between different supersymmetric vacua. Examples include KKLT models, STU models, type IIB multiple flux vacua, and models with several Minkowski and AdS vacua. After the uplifting, some of the vacua become dS, whereas some others remain AdS. The near-BPS walls separating these vacua may be seen as bubble walls in the theory of vacuum decay. As an outcome of our investigation of the BPS walls, we found that the decay rate of dS vacua to a collapsing space with a negative vacuum energy can be quite large. The parts of space that experience a decay to a collapsing space, or to a Minkowski vacuum, never return back to dS space. The channels of irreversible vacuum decay serve as sinks for the probability flow. The existence of such sinks is a distinguishing feature of the landscape. We show that it strongly affects the probability distributions in string cosmology.

  12. Domain walls, near-BPS bubbles, and probabilities in the landscape

    SciTech Connect (OSTI)

    Ceresole, Anna [INFN and Dipartimento di Fisica Teorica Universita di Torino, Via Pietro Giuria 1, 10125 Turin (Italy); Dall'Agata, Gianguido [Physics Department, Theory Unit, CERN, CH 1211, Geneva 23 (Switzerland); Giryavets, Alexander; Kallosh, Renata; Linde, Andrei [Department of Physics, Stanford University, Stanford, California 94305 (United States)

    2006-10-15T23:59:59.000Z

    We develop a theory of static Bogomol'nyi-Prasad-Sommerfield (BPS) domain walls in stringy landscape and present a large family of BPS walls interpolating between different supersymmetric vacua. Examples include Kachru, Kallosh, Linde, Trivedi models, STU models, type IIB multiple flux vacua, and models with several Minkowski and anti-de Sitter vacua. After the uplifting, some of the vacua become de Sitter (dS), whereas some others remain anti-de Sitter. The near-BPS walls separating these vacua may be seen as bubble walls in the theory of vacuum decay. As an outcome of our investigation of the BPS walls, we found that the decay rate of dS vacua to a collapsing space with a negative vacuum energy can be quite large. The parts of space that experience a decay to a collapsing space, or to a Minkowski vacuum, never return back to dS space. The channels of irreversible vacuum decay serve as sinks for the probability flow. The existence of such sinks is a distinguishing feature of the landscape. We show that it strongly affects the probability distributions in string cosmology.

  13. A Lattice Study of the Nucleon Excited States with Domain Wall Fermions

    E-Print Network [OSTI]

    Shoichi Sasaki; Tom Blum; Shigemi Ohta

    2002-01-16T23:59:59.000Z

    We present results of our numerical calculation of the mass spectrum for isospin one-half and spin one-half non-strange baryons, i.e. the ground and excited states of the nucleon, in quenched lattice QCD. We use a new lattice discretization scheme for fermions, domain wall fermions, which possess almost exact chiral symmetry at non-zero lattice spacing. We make a systematic investigation of the negative-parity $N^*$ spectrum by using two distinct interpolating operators at $\\beta=6/g^2=6.0$ on a $16^3 \\times 32 \\times 16$ lattice. The mass estimates extracted from the two operators are consistent with each other. The observed large mass splitting between this state, $N^*(1535)$, and the positive-parity ground state, the nucleon N(939), is well reproduced by our calculations. We have also calculated the mass of the first positive-parity excited state and found that it is heavier than the negative-parity excited state for the quark masses studied.

  14. Nucleon structure functions from dynamical (2+1)-flavor domain wall fermions

    E-Print Network [OSTI]

    Shigemi Ohta; for the RBC; UKQCD Collaborations

    2009-11-13T23:59:59.000Z

    We report lattice-volume independence of low moments of nucleon structure functions from the coarse RIKEN-BNL-Columbia (RBC) and UKQCD joint dynamical (2+1)-flavor domain-wall fermions (DWF) ensembles at the lattice cut off of (a^{-1}\\sim1.7) GeV. The isovector quark momentum fraction, (_{u-d}), and helicity fraction, (_{\\Delta u - \\Delta d}), both fully non-perturbatively renormalized are studied on two spatial volumes of ((\\sim {\\rm 2.7 fm})^3) and ((\\sim {\\rm 1.8 fm})^3). Their naturally renormalized ratio, (_{u-d}/_{\\Delta u - \\Delta d}), is not affected by any finite-size effect. It does not depend strongly on light quark mass and does agree well with the experiment. The respective absolute values, fully non-perturbatively renormalized, do not show any finite-size effect either. They show trending toward the respective experimental values at the lightest up- and down-quark mass. This trending down to the experimental values appears to be a real physical effect driven by lighter quarks. The observations are in contrast to the huge finite-size effect seen in the axial-current form factors.

  15. Nucleon structure with dynamical (2+1)-flavor domain wall fermions lattice QCD

    E-Print Network [OSTI]

    Shigemi Ohta; Takeshi Yamazaki

    2008-09-30T23:59:59.000Z

    We report isovector form factors and low moments of isovector structure functions of nucleon from the coarse RIKEN-BNL-Columbia (RBC) and UKQCD joint dynamical (2+1)-flavor domain-wall fermions (DWF) ensembles. The lattice cut off is estimated at (a^{-1}=1.7) GeV. The lattice volume is as large as 2.7 fm across. We carefully optimize the nucleon source/sink separation in time to about 1.4 fm. Unexpectedly large finite-size effect in the axial charge is found. The effect scales with a single variable, the product (m_\\pi L) of the pion mass (m_\\pi) and lattice spatial linear extent (L), and sets in at around (m_\\pi L = 5). We also discuss momentum-transfer dependence of the vector, induced tensor, axial-vector and induced pesudo-scalar form factors. From structure functions, fully non-perturbatively renormalized iso-vector quark momentum fraction, (_{u-d}), helicity fraction, (_{\\Delta u - \\Delta d}), and transversity, (_{\\delta u - \\delta d}), are reported, as well as an unrenormalized twist-3 coefficient, (d_1). The ratio of the momentum to helicity fractions, (_{u-d}/_{\\Delta u - \\Delta d}), does not depend on light quark mass and agree well with the experiment. Their respective absolute values, fully renormalized, shows interesting trending toward the respective experimental values at the lightest light quark mass.

  16. Topology density correlator on dynamical domain-wall ensembles with nearly frozen topological charge

    E-Print Network [OSTI]

    JLQCD collaboration; H. Fukaya; S. Aoki; G. Cossu; S. Hashimoto; T. Kaneko; J. Noaki

    2014-11-13T23:59:59.000Z

    Global topological charge decorrelates very slowly or even freezes in fine lattice simulations. On the other hand, its local fluctuations are expected to survive and lead to the correct physical results as long as the volume is large enough. We investigate this issue on recently generated configurations including dynamical domain-wall fermions at lattice spacings a = 0.08 fm and finer. We utilize the Yang-Mills gradient flow to define the topological charge density operator and calculate its long-distance correlation, through which we propose a new method for extracting the topological susceptibility in a sub-volume. This method takes care of the finite volume correction, which reduces the bias caused by the global topological charge. Our lattice data clearly show a shorter auto-correlation time than that of the naive definition using the whole lattice, and are less sensitive to the global topological history. Numerical results show a clear sea-quark mass dependence, which agrees well with the prediction of chiral perturbation theory.

  17. Continuum limit physics from 2+1 flavor domain wall QCD

    SciTech Connect (OSTI)

    Aoki, Y.; Izubuchi, T.; Arthur, R.; Blum, T.; Boyle, P.A.; Brommel, D.; Christ, N.H.; Dawson, C.; Flynn, J.M.; Jin, X.Y.; Jung, C.; Kelly, C.; Li, M.; Lichtl, A.; Lightman, M.; Lin, M.F.; Mawhinney, R.D.; Maynard,C.M.; Ohta, S.; Pendleton, B.J.; Sachrajda, C.T.; Scholz, E.E.; Soni, A.; Wennekers, J.; Zanotti, J.M.; Zhou, R.

    2011-04-22T23:59:59.000Z

    We present physical results obtained from simulations using 2+1 flavors of domain wall quarks and the Iwasaki gauge action at two values of the lattice spacing a, [a{sup -1} = 1.73(3) GeV and a{sup -1} = 2.28(3) GeV]. On the coarser lattice, with 24{sup 3} x 64 x 16 points (where the 16 corresponds to L{sub s}, the extent of the 5th dimension inherent in the domain wall fermion formulation of QCD), the analysis of C. Allton et al. Phys. Rev. D 78 is extended to approximately twice the number of configurations. The ensembles on the finer 32{sup 3} x 64 x 16 lattice are new. We explain in detail how we use lattice data obtained at several values of the lattice spacing and for a range of quark masses in combined continuum-chiral fits in order to obtain results in the continuum limit and at physical quark masses. We implement this procedure for our data at two lattice spacings and with unitary pion masses in the approximate range 290-420 MeV (225-420 MeV for partially quenched pions). We use the masses of the {pi} and K mesons and the {Omega} baryon to determine the physical quark masses and the values of the lattice spacing. While our data in the mass ranges above are consistent with the predictions of next-to-leading order SU(2) chiral perturbation theory, they are also consistent with a simple analytic ansatz leading to an inherent uncertainty in how best to perform the chiral extrapolation that we are reluctant to reduce with model-dependent assumptions about higher order corrections. In some cases, particularly for f{sub {pi}}, the pion leptonic decay constant, the uncertainty in the chiral extrapolation dominates the systematic error. Our main results include f{sub {pi}} = 124(2){sub stat}(5){sub syst} MeV, f{sub K}/f{sub {pi}} = 1.204(7)(25) where f{sub K} is the kaon decay constant, m{sub s}{sup MS} (2 GeV) = (96.2 {+-} 2.7) MeV and m{sub ud}{sup MS} (2 GeV) = (3.59 {+-} 0.21) MeV (m{sub s}/m{sub ud} = 26.8 {+-} 1.4) where m{sub s} and m{sub ud} are the mass of the strange quark and the average of the up and down quark masses, respectively, [{Sigma}{sup MS} (2 GeV)]{sup 1/3} = 256(6) MeV, where {Sigma} is the chiral condensate, the Sommer scale r{sub 0} = 0.487(9) fm and r{sub 1} = 0.333(9) fm.

  18. Nucleon isovector structure functions in (2+1)-flavor QCD with domain wall fermions

    E-Print Network [OSTI]

    Yasumichi Aoki; Tom Blum; Huey-Wen Lin; Shigemi Ohta; Shoichi Sasaki; Robert Tweedie; Takeshi Yamazaki; James Zanotti

    2010-03-17T23:59:59.000Z

    We report on numerical lattice QCD calculations of some of the low moments of the nucleon structure functions. The calculations are carried out with gauge configurations generated by the RBC and UKQCD collaborations with (2+1)-flavors of dynamical domain wall fermions and the Iwasaki gauge action ($\\beta = 2.13$). The inverse lattice spacing is $a^{-1} = 1.73$ GeV, and two spatial volumes of ((2.7{\\rm fm})^3) and ((1.8 {\\rm fm})^3) are used. The up and down quark masses are varied so the pion mass lies between 0.33 and 0.67 GeV while the strange mass is about 12 % heavier than the physical one. The structure function moments we present include fully non-perturbatively renormalized iso-vector quark momentum fraction, (_{u-d}), helicity fraction, (_{\\Delta u - \\Delta d}), and transversity, (_{\\delta u - \\delta d}), as well as an unrenormalized twist-3 coefficient, (d_1). The ratio of the momentum to helicity fractions, (_{u-d}/_{\\Delta u - \\Delta d}), does not show dependence on the light quark mass and agrees well with the value obtained from experiment. Their respective absolute values, fully renormalized, show interesting trends toward their respective experimental values at the lightest quark mass. A prediction for the transversity, (0.7 _{\\delta u -\\delta d} < 1.1), in the (\\bar{\\rm MS}) scheme at 2 GeV is obtained. The twist-3 coefficient, (d_1), though yet to be renormalized, supports the perturbative Wandzura-Wilczek relation.

  19. Nucleon structure with two flavors of dynamical domain-wall fermions

    E-Print Network [OSTI]

    Huey-Wen Lin; Tom Blum; Shigemi Ohta; Shoichi Sasaki; Takeshi Yamazaki

    2008-02-06T23:59:59.000Z

    We present a numerical lattice quantum chromodynamics calculation of isovector form factors and the first few moments of the isovector structure functions of the nucleon. The calculation employs two degenerate dynamical flavors of domain-wall fermions, resulting in good control of chiral symmetry breaking. Non-perturbative renormalization of the relevant quark currents is performed where necessary. The inverse lattice spacing, $a^{-1}$, is about 1.7 GeV. We use degenerate up and down dynamical quark masses around 1, 3/4 and 1/2 the strange quark mass. The physical volume of the lattice is about $(1.9{fm})^3$. The ratio of the isovector vector to axial charges, $g_A/g_V$, trends a bit lower than the experimental value as the quark mass is reduced toward the physical point. We calculate the momentum-transfer dependences of the isovector vector, axial, induced tensor and induced pseudoscalar form factors. The Goldberger-Treiman relation holds at low momentum transfer and yields a pion-nucleon coupling, $g_{\\pi NN} = 15.5(1.4)$, where the quoted error is only statistical. We find that the flavor non-singlet quark momentum fraction $_{u-d}$ and quark helicity fraction $_{\\Delta u-\\Delta d}$ overshoot their experimental values after linear chiral extrapolation. We obtain the transversity, $_{\\delta u-\\delta d} = 0.93(6)$ in $\\bar{\\rm MS}$ at 2 GeV and a twist-3 polarized moment, $d_1$, appears small, suggesting that the Wandzura-Wilczek relation holds approximately. We discuss the systematic errors in the calculation, with particular attention paid to finite-volume effects, excited-state contamination, and chiral extrapolations.

  20. Nucleon structure in lattice QCD with dynamical domain-wall fermions quarks

    E-Print Network [OSTI]

    Huey-Wen Lin; Shigemi Ohta

    2006-10-10T23:59:59.000Z

    We report RBC and RBC/UKQCD lattice QCD numerical calculations of nucleon electroweak matrix elements with dynamical domain-wall fermions (DWF) quarks. The first, RBC, set of dynamical DWF ensembles employs two degenerate flavors of DWF quarks and the DBW2 gauge action. Three sea quark mass values of 0.04, 0.03 and 0.02 in lattice units are used with about 200 gauge configurations each. The lattice cutoff is about 1.7 GeV and the spatial volume is about (1.9 fm)^3. Despite the small volume, the ratio of the isovector vector and axial charges g_A/g_V and that of structure function moments _{u-d}/_{Delta u - Delta d} are in agreement with experiment, and show only very mild quark mass dependence. The second, RBC/UK, set of ensembles employs one strange and two degenerate (up and down) dynamical DWF quarks and Iwasaki gauge action. The strange quark mass is set at 0.04, and three up/down mass values of 0.03, 0.02 and 0.01 in lattice units are used. The lattice cutoff is about 1.6 GeV and the spatial volume is about (3.0 fm)^3. Even with preliminary statistics of 25-30 gauge configurations, the ratios g_A/g_V and _{u-d}/_{Delta u - Delta d} are consistent with experiment and show only very mild quark mass dependence. Another structure function moment, d_1, though yet to be renormalized, appears small in both sets.

  1. Domain Walls and Anchoring Transitions Mimicking Nematic Biaxiality in the Oxadiazole Bent-Core Liquid Crystal C7

    E-Print Network [OSTI]

    Young-ki Kim; Greta Cukrov; Jie Xiang; Sung-Tae Shin; Oleg D. Lavrentovich

    2015-03-23T23:59:59.000Z

    We investigate the origin of secondary disclinations that were recently described as a new evidence of a biaxial nematic phase in an oxadiazole bent-core thermotropic liquid crystal C7. With an assortment of optical techniques such as polarizing optical microscopy, LC PolScope, and fluorescence confocal polarizing microscopy, we demonstrate that the secondary disclinations represent non-singular domain walls formed in an uniaxial nematic during the surface anchoring transition, in which surface orientation of the director changes from tangential (parallel to the bounding plates) to tilted. Each domain wall separates two regions with the director tilted in opposite azimuthal directions. At the centre of the wall, the director remains parallel to the bonding plates. The domain walls can be easily removed by applying a modest electric field. The anchoring transition is explained by the balance of (a) the intrinsic perpendicular surface anchoring produced by the polyimide aligning layer and (b) tangential alignment caused by ionic impurities forming electric double layers. The model is supported by the fact that the temperature of the tangential-tilted anchoring transition decreases as the cell thickness increases and as the concentration of ionic species (added salt) increases. We also demonstrate that the surface alignment is strongly affected by thermal degradation of the samples. The study shows that C7 exhibits only a uniaxial nematic phase and demonstrate yet another mechanism (formation of secondary disclinations) by which a uniaxial nematic can mimic a biaxial nematic behaviour.

  2. Physical Properties of Wave Motion in Inclined Magnetic Fields Within Sunspot Penumbrae

    E-Print Network [OSTI]

    H. Schunker; D. C. Braun; C. Lindsey; P. S. Cally

    2008-04-22T23:59:59.000Z

    At the surface of the Sun, acoustic waves appear to be affected by the presence of strong magnetic fields in active regions. We explore the possibility that the inclined magnetic field in sunspot penumbrae may convert primarily vertically propagating acoustic waves into elliptical motion. We use helioseismic holography to measure the modulus and phase of the correlation between incoming acoustic waves and the local surface motion within two sunspots. These correlations are modeled assuming the surface motion is elliptical, and we explore the properties of the elliptical motion on the magnetic field inclination. We also demonstrate that the phase shift of the outward propagating waves is opposite to the phase shift of the inward propagating waves in stronger, more vertical fields, but similar to the inward phase shifts in weaker, more inclined fields.

  3. Nucleon transverse momentum-dependent parton distributions from domain wall fermion calculations at 297 MeV pion mass

    SciTech Connect (OSTI)

    Engelhardt, Michael; Musch, Bernhard; Bhattacharya, Tanmoy; Gupta, Rajan; Hagler, Phillip; Negele, John; Pochinsky, Andrew; Shafer, Andreas; Syritsyn, Sergey; Yoon, Boram

    2014-12-01T23:59:59.000Z

    Lattice QCD calculations of transverse momentum-dependent parton distributions (TMDs) in a nucleon are performed based on a definition of TMDs via hadronic matrix elements of quark bilocal operators containing staple-shaped gauge connections. A parametrization of the matrix elements in terms of invariant amplitudes serves to cast them in the Lorentz frame preferred for the lattice calculation. Using a RBC/UKQCD domain wall fermion ensemble corresponding to a pion mass of 297MeV, on a lattice with spacing 0.084fm, selected TMD observables are accessed and compared to previous explorations at heavier pion masses on coarser lattices.

  4. Non-perturbative renormalization of bilinear operators with Möbius domain-wall fermions in the coordinate space

    E-Print Network [OSTI]

    M. Tomii; G. Cossu; S. Hashimoto; J. Noaki

    2014-11-25T23:59:59.000Z

    We study the non-perturbative determination of the renormalization constants of flavor non-singlet quark bilinear operators on the lattice. The renormalization condition is imposed on correlation functions of bilinear operators in the coordinate space. The results are converted to the value at 2 GeV in the $\\rm\\overline{MS}$ scheme by a perturbative matching. The calculation is carried out on gauge configurations generated with the Mobius domain-wall fermions at two lattice spacings $a^{-1} = 2.4$ GeV and $a^{-1} = 3.6$ GeV.

  5. Dynamics of skyrmions in chiral magnets: Dynamic phase transitions and equation of motion

    SciTech Connect (OSTI)

    Lin, Shi-Zeng, E-mail: szl@lanl.gov; Reichhardt, Charles; Batista, Cristian D.; Saxena, Avadh [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-05-07T23:59:59.000Z

    We study the dynamics of skyrmions in a metallic chiral magnet. First, we show that skyrmions can be created dynamically by destabilizing the ferromagnetic background state through a spin polarized current. We then treat skyrmions as rigid particles and derive the corresponding equation of motion. The dynamics of skyrmions is dominated by the Magnus force, which accounts for the weak pinning of skyrmions observed in experiments. Finally, we discuss the quantum motion of skyrmions.

  6. Modeling Left Ventricle Wall Motion Using Tagged Magnetic Resonance Imaging

    E-Print Network [OSTI]

    Alenezy, Mohammed D.

    2009-04-17T23:59:59.000Z

    can be calculated as M = ?nullN 2 tanh( ?nullB 0 2kT ) (2.3) In a biological sample that contains about 1mL of water, there are about 10 22 hydrogen nuclei, and at the room... population that is frequently in need of quality tomographic images for the assessment of congenital heart defects. MRI can characterize myocardial function through the use of cine MRI and tagged MRI. The latter provides a means to assess wall motion...

  7. Two-dimensional single-stream electron motion in a coaxial diode with magnetic insulation

    SciTech Connect (OSTI)

    Fuks, Mikhail I.; Schamiloglu, Edl [Department of Electrical and Computer Engineering, MSC01 1100, University of New Mexico, Albuquerque, New Mexico 87131-0001 (United States)] [Department of Electrical and Computer Engineering, MSC01 1100, University of New Mexico, Albuquerque, New Mexico 87131-0001 (United States)

    2014-05-15T23:59:59.000Z

    One of the most widespread models of electrons drifting around the cathode in magnetrons is the single-stream state, which is the Brillouin stream with purely azimuthal motion. We describe a single-stream state in which electrons not only move in the azimuthal direction, but also along the axial direction, which is useful for consideration, for example, of relativistic magnetrons, MILOs, and coaxial transmission lines. Relations are given for the conditions of magnetic insulation for 2D electron motion, for 1D azimuthal and axial motion, and for synchronism of these streams with the operating waves of M-type microwave sources. Relations are also provided for the threshold of generation in magnetrons with 2D electron motion.

  8. Stochastic Noncircular Motion and Outflows Driven by Magnetic Activity in the Galactic Bulge Region

    E-Print Network [OSTI]

    Suzuki, Takeru K; Torii, Kazufumi; Machida, Mami; Matsumoto, Ryoji

    2015-01-01T23:59:59.000Z

    By performing a global magneto-hydrodynamical simulation for the Milky Way with an axisymmetric gravitational potential, we propose that spatially dependent amplification of magnetic fields possibly explains the observed noncircular motion of the gas in the Galactic center region. The radial distribution of the rotation frequency in the bulge region is not monotonic in general. The amplification of the magnetic field is enhanced in regions with stronger differential rotation, because magnetorotational instability and field-line stretching are more effective. The strength of the amplified magnetic field reaches >~ 0.5 mG, and radial flows of the gas are excited by the inhomogeneous transport of angular momentum through turbulent magnetic field that is amplified in a spatially dependent manner. In addition, the magnetic pressure-gradient force also drives radial flows in a similar manner. As a result, the simulated position-velocity diagram exhibits a time-dependent asymmetric parallelogram-shape owing to the i...

  9. Non-perturbative renormalization of overlap quark bilinears on 2+1-flavor domain wall fermion configurations

    E-Print Network [OSTI]

    Zhaofeng Liu; Ying Chen; Shao-Jing Dong; Michael Glatzmaier; Ming Gong; Anyi Li; Keh-Fei Liu; Yi-Bo Yang; Jian-Bo Zhang

    2014-08-19T23:59:59.000Z

    We present renormalization constants of overlap quark bilinear operators on 2+1-flavor domain wall fermion configurations. This setup is being used by the chiQCD collaboration in calculations of physical quantities such as strangeness in the nucleon and the strange and charm quark masses. The scale independent renormalization constant for the axial vector current is computed using the Ward Identity. The renormalization constants for scalar, pseudoscalar and vector current are calculated in the RI-MOM scheme. Results in the MS-bar scheme are also given. The step scaling function of quark masses in the RI-MOM scheme is computed as well. The analysis uses, in total, six different ensembles of three sea quarks each on two lattices with sizes 24^3x64 and 32^3x64 at spacings a=(1.73 GeV)^{-1} and (2.28 GeV)^{-1}, respectively.

  10. nature materials | ADVANCE ONLINE PUBLICATION | www.nature.com/naturematerials 1 Domain-wall superconductivity in

    E-Print Network [OSTI]

    Moshchalkov, Victor V.

    can be used in the S/F hybrids: individual magnetic dots12,13 or arrays of these14 , and non-patterned ferromagnetic thin films with bubble domains15 . Depending on the domain structure of the ferromagnet, theory3

  11. Proper Motions of OH Masers and Magnetic Fields in Massive Star-Forming Regions

    E-Print Network [OSTI]

    Vincent L. Fish; Mark J. Reid

    2007-08-08T23:59:59.000Z

    We present data of proper motions of OH masers in the massive star-forming regions ON 1, K3-50, and W51 Main/South. OH maser motions in ON 1 are consistent with expansion at approximately 5 km/s, likely tracing the expanding ultracompact H II region. Motions in K3-50 are faster and may be indicating the final stages of OH maser emission in the source, before the OH masers turn off as the H II region transitions from the ultracompact to the compact phase. W51 South shows indications of aspherical expansion, while motions in W51 Main are more difficult to interpret. Nevertheless, it appears that the relative projected separation between W51 Main and W51 South is decreasing, corresponding to an estimate of enclosed mass of at least 1500 solar masses, consistent with estimates derived from millimeter-wavelength dust emission. We confirm the ~20 mG magnetic fields previously seen in W51 Main, which may represent the upper end of the density range allowable for 1665 MHz maser emission. Magnetic field strengths and directions, obtained from Zeeman splitting, in each source are consistent with values obtained in the first epoch four to nine years ago.

  12. Large Magnetic Fields and Motions of OH Masers in W75 N

    E-Print Network [OSTI]

    Vincent L. Fish; Mark J. Reid

    2006-11-02T23:59:59.000Z

    We report on a second epoch of VLBA observations of the 1665 and 1667 MHz OH masers in the massive star-forming region W75 N. We find evidence to confirm the existence of very strong (~40 mG) magnetic fields near source VLA 2. The masers near VLA 2 are dynamically distinct and include a very bright spot apparently moving at 50 km/s relative to those around VLA 1. This fast-moving spot may be an example of a rare class of OH masers seen in outflows in star-forming regions. Due to the variability of these masers and the rapidity of their motions, tracking these motions will require multiple observations over a significantly shorter time baseline than obtained here. Proper motions of the masers near VLA 1 are more suggestive of streaming along magnetized shocks rather than Keplerian rotation in a disk. The motions of the easternmost cluster of masers in W75 N (B) may be tracing slow expansion around an unseen exciting source.

  13. Motion of free spins and NMR imaging without a radio-frequency magnetic field

    E-Print Network [OSTI]

    Kees van Schenk Brill; Jassem Lahfadi; Tarek Khalil; Daniel Grucker

    2015-04-19T23:59:59.000Z

    NMR imaging without any radio-frequency magnetic field is explained by a quantum treatment of independent spin~$\\tfrac 12$. The total magnetization is determined by means of their individual wave function. The theoretical treatment, based on fundamental axioms of quantum mechanics and solving explicitly the Schr\\"{o}dinger equation with the kinetic energy part which gives the motion of free spins, is recalled. It explains the phase shift of the spin noise spectrum with its amplitude compared to the conventional NMR spectrum. Moreover it explains also the relatively good signal to noise ratio of NMR images obtained without a RF pulse. This derivation should be helpful for new magnetic resonance imaging sequences or for developing quantum computing by NMR.

  14. Finite temperature QCD using 2+1 flavors of domain wall fermions at N{sub t}=8

    SciTech Connect (OSTI)

    Cheng, Michael; Christ, Norman H.; Li, Min; Mawhinney, Robert D.; Renfrew, Dwight; Hegde, Prasad; Karsch, Frithjof; Lin Meifeng; Vranas, Pavlos [Department of Physics, Columbia University, New York, New York 10027 (United States); Department of Physics and Astronomy, SUNY, Stony Brook, New York 11794-3800 (United States); Physics Department, Brookhaven National Laboratory, Upton, New York 11973, USA and Fakultaet fuer Physik, Universitaet Bielefeld, D-33615 Bielefeld (Germany); Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2010-03-01T23:59:59.000Z

    We study the region of the QCD phase transition using 2+1 flavors of domain wall fermions and a 16{sup 3}x8 lattice volume with a fifth dimension of L{sub s}=32. The disconnected light quark chiral susceptibility, quark number susceptibility, and the Polyakov loop suggest a chiral and deconfining crossover transition lying between 155 and 185 MeV for our choice of quark mass and lattice spacing. In this region the lattice scale deduced from the Sommer parameter r{sub 0} is a{sup -1{approx_equal}}1.3 GeV, the pion mass is {approx_equal}300 MeV, and the kaon mass is approximately physical. The peak in the chiral susceptibility implies a pseudocritical temperature T{sub c}=171(10)(17) MeV where the first error is associated with determining the peak location and the second with our unphysical light quark mass and nonzero lattice spacing. The effects of residual chiral symmetry breaking on the chiral condensate and disconnected chiral susceptibility are studied using several values of the valence L{sub s}.

  15. Fermion masses and mixing in a 4+1 dimensional SU(5) domain-wall brane model

    SciTech Connect (OSTI)

    Callen, Benjamin D.; Volkas, Raymond R. [School of Physics, University of Melbourne, Victoria 3010 (Australia)

    2011-03-01T23:59:59.000Z

    We study the fermion mass and mixing hierarchy problems within the context of the SU(5) 4+1d domain-wall brane model of Davies, George, and Volkas. In this model, the ordinary fermion mass relations of SU(5) grand unified theories are avoided, since the masses are proportional to overlap integrals of the profiles of the electroweak Higgs and the chiral components of each fermion, which are split into different 3+1d hyperplanes according to their hypercharges. We show that the fermion mass hierarchy without electroweak mixing can be generated naturally from these splittings, that generation of the Cabibbo-Kobayashi-Maskawa matrix looks promising, and that the Cabibbo angle, along with the mass hierarchy, can be generated for the case of Majorana neutrinos from a more modest hierarchy of parameters. We also show that, under some assumptions made on the parameter space, the generation of realistic lepton mixing angles is not possible without fine-tuning, which argues for a flavor symmetry to enforce the required relations.

  16. IEEE TRANSACTIONS ON MAGNETICS, VOL. 36, NO. 5, SEPTEMBER 2000 3047 Pulsed-Current-Induced Domain Wall Propagation in

    E-Print Network [OSTI]

    Gomez, Romel D.

    strips with variable length from 100 m to 300 m, and a second set had a "bow-tie" shape with the same vacuum system and evacuated at Torr. NiFe films were deposited on native oxide by thermal evaporation

  17. 3D Controlled Motion of a Microrobot using Magnetic Gradients Karim Belharet, David Folio and Antoine Ferreira

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    3D Controlled Motion of a Microrobot using Magnetic Gradients Karim Belharet, David Folio to allow 3D navigation of a microdevice in blood vessels, namely: (i) vessel path extraction, (ii) magnetic locations in the human body become accessible. Because the method of propulsion should al- low

  18. Nucleon form factors and structure functions with N_f=2+1 dynamical domain wall fermions

    E-Print Network [OSTI]

    RBC-UKQCD Collaborations; :; Takeshi Yamazaki; Shigemi Ohta

    2007-10-02T23:59:59.000Z

    We report isovector form factors and low moments of structure functions of nucleon in numerical lattice quantum chromodynamics (QCD) from the on-going calculations by the RIKEN-BNL-Columbia (RBC) and UKQCD Collaborations with (2+1) dynamical flavors of domain-wall fermion (DWF) quarks. We calculate the matrix elements with four light quark masses, corresponding to pion mass values of m_\\pi = 330-670 MeV, while the dynamical strange mass is fixed at a value close to physical, on (2.7 fm)^3 spatial volume. We found that our axial charge, g_A, at the lightest mass exhibits a large deviation from the heavier mass results. This deviation seems to be a finite-size effect as the g_A value scales with a single parameter, m_\\pi L, the product of pion mass and linear spatial lattice size. The scaling is also seen in earlier 2-flavor dynamical DWF and Wilson quark calculations. Without this lightest point, the three heavier mass results show only very mild mass dependence and linearly extrapolate to g_A=1.16(6). We determined the four form factors, the vector (Dirac), induced tensor (Pauli), axial vector and induced pseudoscalar, at a few finite momentum transfer values as well. At the physical pion mass the form-factors root mean square radii determined from the momentum-transfer dependence %of the form factors are 20-30% smaller than the corresonding experiments. The ratio of the isovector quark momentum to helicity fractions, _{u-d}/_{\\Delta u - \\Delta d} is in agreement with experiment without much mass dependence including the lightest point. We obtain an estimate, 0.81(2), by a constant fit. Although the individual momentum and helicity fractions are yet to be renormalized, they show encouraging trend toward experiment.

  19. Real-Time Data Processing and Magnetic Field Pitch Angle Estimation of the JET Motional Stark Effect Diagnostic based on Kalman Filtering

    E-Print Network [OSTI]

    Real-Time Data Processing and Magnetic Field Pitch Angle Estimation of the JET Motional Stark Effect Diagnostic based on Kalman Filtering

  20. Phase-field simulation of strain-induced domain switching in magnetic thin films

    E-Print Network [OSTI]

    Chen, Long-Qing

    Phase-field simulation of strain-induced domain switching in magnetic thin films Jia-Mian Hu, G of the Bloch point in a magnetic film with strong uniaxial magnetic anisotropy Low Temp. Phys. 37, 690 (2011) Evolution of magnetic bubble domains in manganite films Appl. Phys. Lett. 99, 042503 (2011) 360° domain wall

  1. Temperature dependent nucleation, propagation, and annihilation of domain walls in all-perpendicular spin-valve nanopillars

    SciTech Connect (OSTI)

    Gopman, D. B., E-mail: daniel.gopman@physics.nyu.edu; Kent, A. D. [Department of Physics, New York University, New York, New York 10003 (United States); Bedau, D. [Department of Physics, New York University, New York, New York 10003 (United States); HGST San Jose Research Center, San Jose, California 95135 (United States); Mangin, S. [Institut Jean Lamour, UMR CNRS 7198 Université de Lorraine, Nancy, France 54506 (France); Fullerton, E. E. [CMRR, University of California at San Diego, La Jolla, California 92093 (United States); Katine, J. A. [HGST San Jose Research Center, San Jose, California 95135 (United States)

    2014-03-21T23:59:59.000Z

    We present a study of the temperature dependence of the switching fields in Co/Ni-based perpendicularly magnetized spin-valves. While magnetization reversal of all-perpendicular Co/Ni spin valves at ambient temperatures is typically marked by a single sharp step change in resistance, low temperature measurements can reveal a series of resistance steps, consistent with non-uniform magnetization configurations. We propose a model that consists of domain nucleation, propagation, and annihilation to explain the temperature dependence of the switching fields. Interestingly, low temperature (<30?K) step changes in resistance that we associate with domain nucleation have a bimodal switching field and resistance step distribution, attributable to two competing nucleation pathways.

  2. Regulation and large motion tracking for active magnetic bearing system using sliding mode control

    E-Print Network [OSTI]

    Sun, Guangyoung

    1999-01-01T23:59:59.000Z

    tracking of the nonlinear rotor AMB system. For the regulation of rotor, the vertical rotor AMB system with the imbalance disturbance due to the eccentricity of mass is considered for cylindrical and conical mode initial conditions. For the large motion...

  3. 140 IEEE TRANSACTIONS ON MAGNETICS, VOL. 41, NO. 1, JANUARY 2005 Letter___________________________________________________________________________________________

    E-Print Network [OSTI]

    Vu-Quoc, Loc

    , self-heating, and a risk of thermal-runaway failure [2]. Based on domain-wall motion theory [3 Thai Government. P. Nakmahachalasint is with the Department of Electrical and Computer Engineering is with the Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL 32611-6130 USA (e

  4. Effects of demagnetizing factors on transient motion of ferrofluid in a uniform rotating magnetic field

    E-Print Network [OSTI]

    Snively, Michael John

    2011-01-01T23:59:59.000Z

    The mechanisms that lead to bulk flow within a ferrofluid-filled container subjected to a rotating uniform magnetic field are experimentally studied. There are two prevailing theories: spin diffusion theory and flow due ...

  5. Reversal mechanisms of coupled bi-component magnetic nanostructures G. Shimon,1,2

    E-Print Network [OSTI]

    Adeyeye, Adekunle

    in applications such as high density information storage,1­3 domain wall (DW) logic,4,5 and memory devices.6Reversal mechanisms of coupled bi-component magnetic nanostructures G. Shimon,1,2 A. O. Adeyeye,1 Institute of Physics. [http://dx.doi.org/10.1063/1.4747446] Thin film ferromagnetic nanostructures have been

  6. Interfacial current-induced torques in Pt/Co/GdOx

    E-Print Network [OSTI]

    Emori, Satoru

    Current-driven domain wall (DW) motion is investigated in Pt/Co/GdOx nanostrips with perpendicular magnetic anisotropy. Measurements of the propagation field and the energy barrier for thermally activated DW motion reveal ...

  7. Investigating plasma motion of magnetic clouds at 1 AU through a velocity-modified cylindrical force-free flux rope model

    E-Print Network [OSTI]

    Wang, Yuming; Shen, Chenglong; Liu, Rui; Wang, S

    2015-01-01T23:59:59.000Z

    Magnetic clouds (MCs) are the interplanetary counterparts of coronal mass ejections (CMEs), and usually modeled by a flux rope. By assuming the quasi-steady evolution and self-similar expansion, we introduce three types of global motion into a cylindrical force-free flux rope model, and developed a new velocity-modified model for MCs. The three types of the global motion are the linear propagating motion away from the Sun, the expanding and the poloidal motion with respect to the axis of the MC. The model is applied to 72 MCs observed by Wind spacecraft to investigate the properties of the plasma motion of MCs. First, we find that some MCs had a significant propagation velocity perpendicular to the radial direction, suggesting the direct evidence of the CME's deflected propagation and/or rotation in interplanetary space. Second, we confirm the previous results that the expansion speed is correlated with the radial propagation speed and most MCs did not expand self-similarly at 1 AU. In our statistics, about 6...

  8. Real-time data processing and magnetic field pitch angle estimation of the JET motional Stark effect diagnostic based on Kalman filtering

    SciTech Connect (OSTI)

    Coelho, R.; Alves, D. [Instituto de Plasmas e Fusao Nuclear, Associacao Euratom/IST, 1049-001 Lisboa (Portugal); Hawkes, N.; Brix, M. [Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Collaboration: JET EFDA Contributors

    2009-06-15T23:59:59.000Z

    A novel technique for the real-time measurement of the magnetic field pitch angle in JET discharges using the motional Stark effect diagnostic is presented. Kalman filtering techniques are adopted to estimate the amplitude of the avalanche photodiode signals' harmonics that are relevant for the pitch angle calculation. The proposed technique {l_brace}for extended technical details of the generic algorithm see [R. Coelho and D. Alves, IEEE Trans. Plasma Sci. 37, 164 (2009)]{r_brace} is shown to be much more robust and provides less noisy estimates than an equivalent lock-in amplifier scheme, in particular when dealing with edge localized modes.

  9. Magnetic study of M-type doped barium hexaferrite nanocrystalline particles

    SciTech Connect (OSTI)

    Alsmadi, A. M., E-mail: abdel.alsmadi@ku.edu.kw [Physics Department, Kuwait University, 13060 Safat (Kuwait); Physics Department, The Hashemite University, 13115 Zarqa (Jordan); Bsoul, I. [Physics Department, Al al-Bayt University, Mafraq (Jordan); Mahmood, S. H. [Physics Department, The University of Jordan, Amman (Jordan); Alnawashi, G. [Physics Department, The Hashemite University, 13115 Zarqa (Jordan); Prokeš, K.; Siemensmeyer, K.; Klemke, B. [Helmholtz Zentrum für Matearialien und Energie, 14109 Berlin (Germany); Nakotte, H. [Physics Department, New Mexico State University, Las Cruces, New Mexico 88003 (United States)

    2013-12-28T23:59:59.000Z

    Co-Ti and Ru-Ti substituted barium ferrite nanocrystalline particles BaFe{sub 12?2x}Co{sub x}Ti{sub x}O{sub 19} with (0?x?1) and BaFe{sub 12?2x}Ru{sub x}Ti{sub x}O{sub 19} with (0?x?0.6) were prepared by ball milling method, and their magnetic properties and their temperature dependencies were studied. The zero-field-cooled (ZFC) and field-cooled (FC) processes were recorded at low magnetic fields and the ZFC curves displayed a broad peak at a temperature T{sub M}. In all samples under investigation, a clear irreversibility between the ZFC and FC curves was observed below room temperature, and this irreversibility disappeared above room temperature. These results were discussed within the framework of random particle assembly model and associated with the magnetic domain wall motion. The resistivity data showed some kind of a transition from insulator to perfect insulator around T{sub M}. At 2?K, the saturation magnetization slightly decreased and the coercivity dropped dramatically with increasing the Co-Ti concentration x. With Ru-Ti substitution, the saturation magnetization showed small variations, while the coercivity decreased monotonically, recording a reduction of about 73% at x?=?0.6. These results were discussed in light of the single ion anisotropy model and the cationic distributions based on previously reported neutron diffraction data for the CoTi substituted system, and the results of our Mössbauer spectroscopy data for the RuTi substituted system.

  10. Soliton solutions and chaotic motion of the extended Zakharov-Kuznetsov equations in a magnetized two-ion-temperature dusty plasma

    SciTech Connect (OSTI)

    Zhen, Hui-Ling; Tian, Bo, E-mail: tian-bupt@163.com; Wang, Yu-Feng; Sun, Wen-Rong; Liu, Li-Cai [State Key Laboratory of Information Photonics and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

    2014-07-15T23:59:59.000Z

    The extended Zakharov-Kuznetsov (eZK) equation for the magnetized two-ion-temperature dusty plasma is studied in this paper. With the help of Hirota method, bilinear forms and N-soliton solutions are given, and soliton propagation is graphically analyzed. We find that the soliton amplitude is positively related to the nonlinear coefficient A, while inversely related to the dispersion coefficients B and C. We obtain that the soliton amplitude will increase with the mass of the jth dust grain and the average charge number residing on the dust grain decreased, but the soliton amplitude will increase with the equilibrium number density of the jth dust grain increased. Upon the introduction of the periodic external forcing term, both the weak and developed chaotic motions can occur. Difference between the two chaotic motions roots in the inequality between the nonlinear coefficient l{sub 2} and perturbed term h{sub 1}. The developed chaos can be weakened with B or C decreased and A increased. Periodic motion of the perturbed eZK equation can be observed when there is a balance between l{sub 2} and h{sub 1}.

  11. Magnetic Fields above the Surface of aSuperconductor with Internal Magnetism

    SciTech Connect (OSTI)

    Bluhm, Hendrik; /Stanford U., Phys. Dept. /SLAC, SSRl

    2007-06-26T23:59:59.000Z

    The author presents a method for calculating the magnetic fields near a planar surface of a superconductor with a given intrinsic magnetization in the London limit. He computes solutions for various magnetic domain boundary configurations and derives relations between the spectral densities of the magnetization and the resulting field in the vacuum half space, which are useful if the magnetization can be considered as a statistical quantity and its features are too small to be resolved individually. The results are useful for analyzing and designing magnetic scanning experiments. Application to existing data from such experiments on Sr{sub 2}RuO{sub 4} show that a domain wall would have been detectable, but the magnetic field of randomly oriented small domains and small defects may have been smaller than the experimental noise level.

  12. Real-time Magnetic Field Pitch Angle Estimation With a Motional Stark Effect Diagnostic Using Kalman Filtering

    SciTech Connect (OSTI)

    Coelho, R.; Alves, D. [Associacao Euratom/IST, Centro de Fusao Nuclear, 1049-001 Lisboa (Portugal)

    2008-03-12T23:59:59.000Z

    The real-time amplitude estimation of selective harmonics from an Avalanche Photo Diode (APD) signal of a Motion Stark Effect diagnostic is addressed using a Kalman filter. The proposed technique is shown to be much more robust and provide less noisy estimates than a lock-in amplifier scheme. In addition, the negative impact of Edge Localised Modes (ELMs) is minimized, reducing significantly the biasing in the amplitude estimation and ultimately allowing for the pitch angle estimation in the vicinity of the ELM. The inherent biasing in the amplitude estimation due to the 50Hz modulation in the NBI power grid is also easily circumvented with such a technique, rendering dispensable any further filtering of the data.

  13. Motion Constants

    SciTech Connect (OSTI)

    Frank Znidarsic

    2000-11-12T23:59:59.000Z

    A Bose condensate of electrons may exist in nickel hydrogen and palladium hydrogen systems. The motion constants associated with the gravitational and nuclear forces motion tend toward the electromagnetic in these systems. The change in the motion constants produces unexpected gravitomagnetic and nuclear affects.

  14. FINAL REPORT: FG02-01ER-45906 - A novel class of artificially modulated magnetic multilayers based on magnetic shape memory alloys

    SciTech Connect (OSTI)

    Chopra, H. D.

    2005-06-20T23:59:59.000Z

    The temperature dependent micromagnetic behavior, structural phase transitions, magnetic transition, and the dynamics of phase transitions have been investigated using magnetic shape memory alloys. Results provide a novel concept of Â?polymagnetsÂ?. In thin film form the number of martensite variants is greatly reduced. A new technique to study dynamics of magnetic phase transitions has been developed applicable to bulk, thin films or multilayers. Transition pathways in magnetic shape memory alloys are as follows: Structural transitions followed by magnetic transition on cooling, and magnetic transition followed by structural transition on heating. The anisotropy of exchange spring mulilayers is greatly sensitive to substrate constraints, and shows a marked rotational hysteresis at lower temperatures. Results also show that a large reduction in coercivity of multilayers is a direct result of broadening of domain wall width by interlayer magnetostatic interactions.

  15. Magnetization reversal assisted by half antivortex states in nanostructured circular cobalt disks

    SciTech Connect (OSTI)

    Lara, A.; Aliev, F. G., E-mail: farkhad.aliev@uam.es [Dpto. Física de la Materia Condensada, Instituto Nicolas Cabrera (INC) and Condensed Matter Physics Institute (IFIMAC), Universidad Autónoma de Madrid, Madrid (Spain); Dobrovolskiy, O. V. [Physikalisches Institut, Goethe University, Frankfurt am Main (Germany); Physics Department, V. Karazin National University, Kharkiv (Ukraine); Prieto, J. L. [Instituto de Sistemas Optoelectrónicos y Microtecnología (ISOM), Universidad Politecnica de Madrid (Spain); Huth, M. [Physikalisches Institut, Goethe University, Frankfurt am Main (Germany)

    2014-11-03T23:59:59.000Z

    The half antivortex, a fundamental topological structure which determines magnetization reversal of submicron magnetic devices with domain walls, has been suggested also to play a crucial role in spin torque induced vortex core reversal in circular disks. Here, we report on magnetization reversal in circular disks with nanoholes through consecutive metastable states with half antivortices. In-plane anisotropic magnetoresistance and broadband susceptibility measurements accompanied by micromagnetic simulations reveal that cobalt (Co) disks with two and three linearly arranged nanoholes directed at 45° and 135° with respect to the external magnetic field show reproducible step-like changes in the anisotropic magnetoresistance and magnetic permeability due to transitions between different intermediate states mediated by vortices and half antivortices confined to the dot nanoholes and edges, respectively. Our findings are relevant for the development of multi-hole based spintronic and magnetic memory devices.

  16. Colloidal Micromotors: Controlled Directed Motion

    E-Print Network [OSTI]

    Baraban, Larysa; Makarov, Denys; Leiderer, Paul; Erbe, Artur

    2008-01-01T23:59:59.000Z

    Here we demonstrate a synthetic micro-engine, based on long-range controlled movement of colloidal particles, which is induced by a local catalytic reaction. The directed motion at long timescales was achieved by placing specially designed magnetic capped colloids in a hydrogen peroxide solution at weak magnetic fields. The control of the motion of the particles was provided by changes of the concentration of the solution and by varying the strength of the applied magnetic field. Such synthetic objects can then be used not only to understand the fundamental driving processes but also be employed as small motors in biological environments, for example, for the transportation of molecules in a controllable way.

  17. Colloidal Micromotors: Controlled Directed Motion

    E-Print Network [OSTI]

    Larysa Baraban; Christian Kreidler; Denys Makarov; Paul Leiderer; Artur Erbe

    2008-07-10T23:59:59.000Z

    Here we demonstrate a synthetic micro-engine, based on long-range controlled movement of colloidal particles, which is induced by a local catalytic reaction. The directed motion at long timescales was achieved by placing specially designed magnetic capped colloids in a hydrogen peroxide solution at weak magnetic fields. The control of the motion of the particles was provided by changes of the concentration of the solution and by varying the strength of the applied magnetic field. Such synthetic objects can then be used not only to understand the fundamental driving processes but also be employed as small motors in biological environments, for example, for the transportation of molecules in a controllable way.

  18. Angular dependence of the magnetization reversal in exchangebiased Fe/MnF2

    SciTech Connect (OSTI)

    Arenholz, Elke; Liu, Kai

    2005-05-01T23:59:59.000Z

    A detailed study of exchange-biased Fe/MnF{sub 2} bilayers using magneto-optical Kerr Effect shows that the magnetization reversal occurs almost fully through domain wall nucleation and propagation for external fields parallel to the exchange bias direction. For finite angles {phi} between bias and external field the magnetization is aligned perpendicular to the field cooling direction for a limited field range for decreasing fields. For external fields perpendicular to the bias direction the magnetization aligns with the field cooling direction for descending and ascending fields before fully reversing. The field range for which the magnetization is close to perpendicular to the external field can be estimated using a simple effective field model.

  19. Interactive motion planning with motion capture data

    E-Print Network [OSTI]

    Lo, Wan-Yen

    2012-01-01T23:59:59.000Z

    Abe, and Jovan Popovi´c. Interactive simulation of stylizedc. Motion fields for interactive character locomotion. ACMon Computer graphics and interactive techniques, SIGGRAPH ’

  20. Magnetic spectroscopy and microscopy of functional materials

    SciTech Connect (OSTI)

    Jenkins, C.A.

    2011-01-28T23:59:59.000Z

    Heusler intermetallics Mn{sub 2}Y Ga and X{sub 2}MnGa (X; Y =Fe, Co, Ni) undergo tetragonal magnetostructural transitions that can result in half metallicity, magnetic shape memory, or the magnetocaloric effect. Understanding the magnetism and magnetic behavior in functional materials is often the most direct route to being able to optimize current materials for todays applications and to design novel ones for tomorrow. Synchrotron soft x-ray magnetic spectromicroscopy techniques are well suited to explore the the competing effects from the magnetization and the lattice parameters in these materials as they provide detailed element-, valence-, and site-specifc information on the coupling of crystallographic ordering and electronic structure as well as external parameters like temperature and pressure on the bonding and exchange. Fundamental work preparing the model systems of spintronic, multiferroic, and energy-related compositions is presented for context. The methodology of synchrotron spectroscopy is presented and applied to not only magnetic characterization but also of developing a systematic screening method for future examples of materials exhibiting any of the above effects. The chapter progression is as follows: an introduction to the concepts and materials under consideration (Chapter 1); an overview of sample preparation techniques and results, and the kinds of characterization methods employed (Chapter 2); spectro- and microscopic explorations of X{sub 2}MnGa/Ge (Chapter 3); spectroscopic investigations of the composition series Mn{sub 2}Y Ga to the logical Mn{sub 3}Ga endpoint (Chapter 4); and a summary and overview of upcoming work (Chapter 5). Appendices include the results of a Think Tank for the Graduate School of Excellence MAINZ (Appendix A) and details of an imaging project now in progress on magnetic reversal and domain wall observation in the classical Heusler material Co{sub 2}FeSi (Appendix B).

  1. ccsd00000514 Electronic transport through domain walls in ferromagnetic nanowires

    E-Print Network [OSTI]

    , Germany 3 Department of Physics, University of Western Australia, Nedlands WA 6907, Australia We study energy, this coupling is weak, leads to very few spin ips, and a perturbative treatment is possible longitudinal energy are transmitted adiabatically while the electrons at high longitudinal energy

  2. Surface effect on domain wall width in ferroelectrics

    E-Print Network [OSTI]

    2009-10-26T23:59:59.000Z

    Oct 26, 2009 ... ponent of displacement on the boundaries between the dead layer and ... double electric layer is formed due to either the physical dead layer a or intrinsic ..... by the Science and Technology Center in Ukraine, Project. No.

  3. Iran Thomas Auditorium, 8600 Charged Domain Walls in Ferroelectrics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12 Investigation Peer Review 2012Iowa

  4. The Motional Stark Effect diagnostic on Alcator C-Mod

    E-Print Network [OSTI]

    Yuh, Howard Yung-Hao

    2005-01-01T23:59:59.000Z

    A ten channel Motional Stark Effect diagnostic has been installed on Alcator C-Mod to measure the plasma internal magnetic pitch angle profile. The C-Mod MSE measures the local electric field direction by measuring the ...

  5. Motional Spin Relaxation in Large Electric Fields

    E-Print Network [OSTI]

    Schmid, Riccardo; Filippone, B W

    2008-01-01T23:59:59.000Z

    We discuss the precession of spin-polarized Ultra Cold Neutrons (UCN) and $^{3}\\mathrm{He}$ atoms in uniform and static magnetic and electric fields and calculate the spin relaxation effects from motional $v\\times E$ magnetic fields. Particle motion in an electric field creates a motional $v\\times E$ magnetic field, which when combined with collisions, produces variations of the total magnetic field and results in spin relaxation of neutron and $^{3}\\mathrm{He}$ samples. The spin relaxation times $T_{1}$ (longitudinal) and $T_{2}$ (transverse) of spin-polarized UCN and $^{3}\\mathrm{He}$ atoms are important considerations in a new search for the neutron Electric Dipole Moment at the SNS \\emph{nEDM} experiment. We use a Monte Carlo approach to simulate the relaxation of spins due to the motional $v\\times E$ field for UCN and for $^{3}\\mathrm{He}$ atoms at temperatures below $600 \\mathrm{mK}$. We find the relaxation times for the neutron due to the $v\\times E$ effect to be long compared to the neutron lifetime, ...

  6. Motional Spin Relaxation in Large Electric Fields

    E-Print Network [OSTI]

    Riccardo Schmid; B. Plaster; B. W. Filippone

    2008-07-02T23:59:59.000Z

    We discuss the precession of spin-polarized Ultra Cold Neutrons (UCN) and $^{3}$He atoms in uniform and static magnetic and electric fields and calculate the spin relaxation effects from motional $v\\times E$ magnetic fields. Particle motion in an electric field creates a motional $v\\times E$ magnetic field, which when combined with collisions, produces variations of the total magnetic field and results in spin relaxation of neutron and $^{3}$He samples. The spin relaxation times $T_{1}$ (longitudinal) and $T_{2}$ (transverse) of spin-polarized UCN and $^{3}$He atoms are important considerations in a new search for the neutron Electric Dipole Moment at the SNS \\emph{nEDM} experiment. We use a Monte Carlo approach to simulate the relaxation of spins due to the motional $v\\times E$ field for UCN and for $^{3}$He atoms at temperatures below $600,\\mathrm{mK}$. We find the relaxation times for the neutron due to the $v\\times E$ effect to be long compared to the neutron lifetime, while the $^{3}$He relaxation times may be important for the \\emph{nEDM} experiment.

  7. 5. Wavelengths and periods of field motions

    E-Print Network [OSTI]

    Finlay, Christopher

    . Using a technique based on the Radon transform [2], we determined the amount of power propagating5. Wavelengths and periods of field motions 2D frequency-wavenumber (FK) power spectra were of the large scale magnetic field at the surface of the core. Here we deconstruct such a model (gufm1

  8. Motion Integration Using Competitive Priors

    E-Print Network [OSTI]

    Wu, Shuang; Lu, Hongjing; Lee, Alan; Yuille, Alan

    2009-01-01T23:59:59.000Z

    to investigate motion integration across orientation andspace. VSS 2006. Motion integration using competitive priorsMotion integration using competitive priors Shuang Wu 1 ,

  9. Motion Integration Using Competitive Priors

    E-Print Network [OSTI]

    Shuang Wu; Hongjing Lu; Alan Lee; Alan Yuille

    2011-01-01T23:59:59.000Z

    to investigate motion integration across orientation andspace. VSS 2006. Motion integration using competitive priorsMotion integration using competitive priors Shuang Wu 1 ,

  10. Imitating Human Dance Motions through Motion Structure Analysis

    E-Print Network [OSTI]

    Ikeuchi, Katsushi

    to apply this idea for importing human dance motions into humanoid robots. Our project overview is shown and Technology Abstract This paper presents the method for importing human dance motion into humanoid robots-kinematics and dynamic balancing technique. Keywords: human motion, humanoid robot, motion prim- itive, motion capture

  11. Bibliography 1. Motion Perception

    E-Print Network [OSTI]

    Rheingans, Penny

    and Patrick R. Green (1990), Visual Perception: Physiology, Psychology, and Ecology, 2nd edition, LawrenceBibliography 1. Motion Perception E. H. Adelson and J. R. Bergen. Spatiotemporal energy models for the perception of motion. Journal of the Optical Society of America, A, 2:284-299, February 1985. O. Braddick

  12. Spatial modulation of in-plane magnetic anisotropy in epitaxial Co(111) films grown on macrostep-bunched Si(111)

    SciTech Connect (OSTI)

    Davydenko, A. V., E-mail: avdavydenko@gmail.com; Kozlov, A. G.; Chebotkevich, L. A. [Laboratory of Thin Film Technologies, Far Eastern Federal University, Vladivostok 690950 (Russian Federation)

    2014-10-14T23:59:59.000Z

    We compared magnetic properties of epitaxial Co(111) films grown on microstep- and macrostep-bunched vicinal Si(111) substrates. A surface of the microstep-bunched Si(111) substrate represents regular array of step-bunches with height of 1.7 nm divided from each other by flat microterraces with a width of 34 nm. A surface of the macrostep-bunched Si(111) substrate is constituted by macrostep bunches with a height of 75–85 nm divided by atomically flat macroterraces. The average sum width of a macrostep bunch and a macroterrace is 2.3 ?m. While in-plane magnetic anisotropy was spatially uniform in Co(111) films grown on the microstep-bunched Si(111), periodic macromodulation of the topography of the Si(111) substrate induced spatial modulation of in-plane magnetic anisotropy in Co(111) film grown on the macrostep-bunched Si(111) surface. The energy of uniaxial magnetic anisotropy in the areas of the Co(111) film deposited on the Si(111) macrosteps was higher more than by the order of magnitude than the energy of the magnetic anisotropy in the areas grown on macroterraces. Magnetization reversal in the areas with different energy of the magnetic anisotropy occurred in different magnetic fields. We showed the possibility of obtaining high density of domain walls in Co(111) film grown on the macrostep-bunched Si(111) by tuning the spatial step density of the Si(111) substrate.

  13. Magnetostatic interaction in nanowires

    E-Print Network [OSTI]

    Siddiqui, Saima Afroz

    2014-01-01T23:59:59.000Z

    Nonvolatile memory and logic devices rely on the manipulation of domain walls in magnetic nanowires, and scaling of these devices requires an understanding of domain wall behavior as a function of the wire width. Due to ...

  14. Symmetries of particle motion

    E-Print Network [OSTI]

    Roy Maartens; David Taylor

    1997-12-11T23:59:59.000Z

    We define affine transport lifts on the tangent bundle by associating a transport rule for tangent vectors with a vector field on the base manifold. The aim is to develop tools for the study of kinetic/ dynamical symmetries in relativistic particle motion. The transport lift unifies and generalises the various existing lifted vector fields, with clear geometric interpretations. We find the affine dynamical symmetries of free particle motion, and compare this to previous results and to the alternative concept of "matter symmetry".

  15. Improved leakage current and ferromagnetic properties in magnetic field annealed BiFeO{sub 3}-based ceramics

    SciTech Connect (OSTI)

    Yin, L.H.; Zhao, B.C. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China)] [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Fang, J.; Zhang, R.R. [High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China)] [High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China); Tang, X.W. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China)] [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Song, W.H., E-mail: whsong@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Dai, J.M. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China)] [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Sun, Y.P., E-mail: ypsun@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China)

    2012-10-15T23:59:59.000Z

    Single-phase Bi{sub 0.85}La{sub 0.15}FeO{sub 3} ceramics were synthesized under various magnetic fields (H{sub a}=0 T, 3 T, 5 T). Substantially reduced leakage current and hence modified ferroelectric (FE) properties were obtained with magnetic field annealing (MA). The largest magnetization and lowest leakage current with large FE polarization (P{sub r}{approx}33 {mu}C/cm{sup 2}) were found in the sample annealed with H{sub a}=3 T. Great changes were also observed in the Raman spectra. All the observed features originate mainly from the different FE domain wall structures induced by MA. These results demonstrate that MA is an effective way to tune the multiferroic and magnetoelectric properties in BiFeO{sub 3}-based materials. - Graphical abstract: Bright field TEM micrograph of the representative domain structures in the samples (a) BLF0, (b) BLF3 and (c) BLF5. Highlights: Black-Right-Pointing-Pointer Bi{sub 0.85}La{sub 0.15}FeO{sub 3} ceramics were synthesized under various magnetic fields. Black-Right-Pointing-Pointer Substantially reduced leakage current with improved ferroelectricity were obtained. Black-Right-Pointing-Pointer Enhanced magnetization with moderate annealing magnetic field.

  16. Motion detector and analyzer

    DOE Patents [OSTI]

    Unruh, W.P.

    1987-03-23T23:59:59.000Z

    Method and apparatus are provided for deriving positive and negative Doppler spectrum to enable analysis of objects in motion, and particularly, objects having rotary motion. First and second returned radar signals are mixed with internal signals to obtain an in-phase process signal and a quadrature process signal. A broad-band phase shifter shifts the quadrature signal through 90/degree/ relative to the in-phase signal over a predetermined frequency range. A pair of signals is output from the broad-band phase shifter which are then combined to provide a first side band signal which is functionally related to a negative Doppler shift spectrum. The distinct positive and negative Doppler spectra may then be analyzed for the motion characteristics of the object being examined.

  17. Human Motion Adrien Treuille

    E-Print Network [OSTI]

    Treuille, Adrien

    of animation in terms of a point cloud driven by the skeleton. Ideally this point cloud is a downsampling for making a transition from the ith frame of the first motion to the jth frame of the second. White values is over the number of points in each point cloud. The weights wi may be chosen both to assign more

  18. Motion Processing and From-from-Apparent-Motion in Infancy

    E-Print Network [OSTI]

    Hirshkowitz, Amy

    2014-08-05T23:59:59.000Z

    Motion-carried information is a salient visual cue used in object perception to parse form in the optical array. The present research examined infants’ ability to extract form shapes in apparent motion stimuli, controlling for color and luminance...

  19. -STABILITY AND VORTEX MOTION IN TYPE II SUPERCONDUCTORS

    E-Print Network [OSTI]

    Spirn, Daniel

    -STABILITY AND VORTEX MOTION IN TYPE II SUPERCONDUCTORS MATTHIAS KURZKE AND DANIEL SPIRN Abstract. 1. Introduction 1.1. Physical background. The evolution of a superconducting material is usu- ally of the magnetic field and the electric field potential for a superconducting sample R2 . The parameter

  20. ur solid Earth undergoes constant change from motions within its core

    E-Print Network [OSTI]

    McLeod, Dennis

    O ur solid Earth undergoes constant change from motions within its core to the surface. Solid Earth is the physical planet we live on, not the oceans or atmosphere. Motions near Earth's cen- ter affect the geodynamo, which generates the Earth's magnetic field. Convection within Earth's mantle drives plate

  1. Generation of Character Motion by Reactive Motion Capture System

    E-Print Network [OSTI]

    Thawonmas, Ruck

    in the human-scale virtual environment. Our purpose is to make character animations with character motion data: Force Feedback, Motion Cap- ture, Human-scale Virtual Environments, Virtual Human 1 Introduction To generate the human motions in virtual envi- ronments made by a computer that are similar to the real world

  2. Motion blur removal from photographs

    E-Print Network [OSTI]

    Cho, Taeg Sang

    2010-01-01T23:59:59.000Z

    One of the long-standing challenges in photography is motion blur. Blur artifacts are generated from relative motion between a camera and a scene during exposure. While blur can be reduced by using a shorter exposure, this ...

  3. Operationalization of Relativistic Motion

    E-Print Network [OSTI]

    Bruno Hartmann

    2015-01-08T23:59:59.000Z

    We apply the Helmholtz program of basic measurements to relativistic motion. We define a spatiotemporal order by practical comparison: "longer than" if one object or process covers the other. To express its value also numerically (how many times more) we cover them by a locally regular grid of light clocks. We define basic measures from physical operations. Interrelation of measurement operations by different observers reveals a genetic derivation of formal Lorentz transformation. Operationally impracticable configurations for accelerating observers clarify the way out of apparent Twin paradox. From simple measurement-methodical principles - without mathematical presuppositions - we derive all equations of relativistic Kinematics (and next same for classical and relativistic Dynamics).

  4. 2. Eastward and westward field motions Method: Radon Transform of TL windows Results

    E-Print Network [OSTI]

    Finlay, Christopher

    determination of azimuthal speeds Christopher Finlay, Mathieu Dumberry, Nicolas Gillet and Andrew Jackson School are driven by magnetic and thermal winds. It is proposed that such processes in Earth's fluid outer core could be responsible for the observed azimuthal field motions. 5. Thermal and magnetic winds

  5. Stochasticity, superadiabaticity, and the theory of adiabatic invariants and guiding center motion

    SciTech Connect (OSTI)

    Dubin, D.H.E.; Krommes, J.A.

    1981-07-01T23:59:59.000Z

    The theory of adiabatic invariants is discussed within the modern framework of symplectic Hamiltonian dynamics. The distinctions between exact, adiabatic, and superadiabatic invariants are clarified. The intimate connection between adiabatic (as opposed to exact) invariance and resonant interactions between motions on disparate time scales is elucidated. For the important case of charged particle motion in a strong magnetic field, resonances between gyration, bounce motion, and an external sinusoidal perturbation are described explicitly by introducing a time-dependent symplectic formulation of the guiding center motion. Destruction of invariance is discussed for quite general situations of physical interest, including the case of a trapped particle in a tokamak.

  6. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

    Goren, Yehuda (Mountain View, CA); Mahale, Narayan K. (The Woodlands, TX)

    1996-01-01T23:59:59.000Z

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

  7. Cyclotron dynamics of interacting bosons in artificial magnetic fields

    E-Print Network [OSTI]

    Xiaopeng Li; S. Das Sarma

    2014-06-24T23:59:59.000Z

    We study theoretically quantum dynamics of interacting bosons in artificial magnetic fields as engineered in recent ultracold atomic experiments, where quantum cyclotron orbital motion has been observed. With exact numerical simulations and perturbative analyses, we find that interactions induce damping in the cyclotron motion. The damping time is found to be dependent on interaction and tunneling strengths monotonically, while its dependence on magnetic flux is non-monotonic. Sufficiently strong interactions would render bosons dynamically localized inhibiting the cyclotron motion. The damping predicted by us can be construed as an interaction-induced quantum decoherence of the cyclotron motion.

  8. Group Motion Editing Taesoo Kwon

    E-Print Network [OSTI]

    Takahashi, Shigeo

    : I.3.7 [Three-Dimensional Graphics and Realism]: Animation--Virtual reality Keywords: Group Motion Editing, Crowd Simulation, Human Motion, Character Animation 1 Introduction Crowd scenes appear frequently in crowd animation make it possible to synthesize convincing animations of virtual crowds by simulating

  9. Motion Capture Technologies Jessica Hodgins

    E-Print Network [OSTI]

    Treuille, Adrien

    a few dof) #12;Production Pipeline #12;What is captured? · Dynamic motions? House of Moves #12;What is captured? · Scale? Motion Analysis #12;What is captured? · Non-rigid objects? House of Moves #12;What is captured? · Props often cause problems ­ Ball in pingpong ­ Fly fishing ­ Sword · Passive behaviors

  10. 06241 Abstracts Collection Human Motion -Understanding, Modeling,

    E-Print Network [OSTI]

    06241 Abstracts Collection Human Motion - Understanding, Modeling, Capture and Animation. 13th Summary Human Motion - Understanding, Modeling, Capture and Animation. 13th Workshop Reinhard Klette 06241 Human Motion - Understanding, Modeling, Capture and Animation. 13th Workshop "Theoretical

  11. Magnetic component of gluon plasma and its viscosity

    E-Print Network [OSTI]

    M. N. Chernodub; H. Verschelde; V. I. Zakharov

    2009-05-15T23:59:59.000Z

    We discuss the role of the magnetic degrees of freedom of the gluon plasma in its viscosity. The main assumption is that motions of the magnetic component and of the rest of the plasma can be considered as independent. The magnetic component in the deconfined phase is described by a three-dimensional (Euclidean) field theory. The parameters of the theory can be estimated phenomenologically, from the lattice data. It is not ruled out that the magnetic component is superfluid.

  12. Optimization of a dual acting, magnetically driven, linear actuator 

    E-Print Network [OSTI]

    Willerton, Justin Ryan

    2002-01-01T23:59:59.000Z

    In this study the geometry of a dual acting, magnetically driven, linear motion actuator will be optimized. This will be accomplished by modeling the system through a set of differential equations to be solved in Matlab. ...

  13. Motion Estimation from Disparity Images

    E-Print Network [OSTI]

    Demirdjian, D.

    2001-05-07T23:59:59.000Z

    A new method for 3D rigid motion estimation from stereo is proposed in this paper. The appealing feature of this method is that it directly uses the disparity images obtained from stereo matching. We assume that the stereo ...

  14. Computer simulation of submarine motion

    E-Print Network [OSTI]

    Zurflueh, Jeffery Alan

    1991-01-01T23:59:59.000Z

    Subject: Mechanical Engineering COMPUTER SIMULATION OF SUBMARINE MOTION A Thesis by JEFFERY ALAN ZURFLUEH Approved as to style and content by: Make McDermott, Jr. ( Chair of Committee ) Glen Williams ( Member ) Lo 4verett ( Member ) gu r Walter...COMPUTER SIMULATION OF SUBMARINE MOTION A Thesis by JEFFERY ALAN ZURFLUEH Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1991 Major...

  15. Solar Radiation and Asteroidal Motion

    E-Print Network [OSTI]

    Jozef Klacka

    2000-09-07T23:59:59.000Z

    Effects of solar wind and solar electromagnetic radiation on motion of asteroids are discussed. The results complete the statements presented in Vokrouhlick\\'{y} and Milani (2000). As for the effect of electromagnetic radiation, the complete equation of motion is presented to the first order in $v/c$ -- the shape of asteroid (spherical body is explicitly presented) and surface distribution of albedo should be taken into account. Optical quantities must be calculated in proper frame of reference.

  16. Maxwell's fluid model of magnetism

    E-Print Network [OSTI]

    Robert Brady; Ross Anderson

    2015-02-20T23:59:59.000Z

    In 1861, Maxwell derived two of his equations of electromagnetism by modelling a magnetic line of force as a `molecular vortex' in a fluid-like medium. Later, in 1980, Berry and colleagues conducted experiments on a `phase vortex', a wave geometry in a fluid which is analogous to a magnetic line of force and also exhibits behaviour corresponding to the quantisation of magnetic flux. Here we unify these approaches by writing down a solution to the equations of motion for a compressible fluid which behaves in the same way as a magnetic line of force. We then revisit Maxwell's historical inspiration, namely Faraday's 1846 model of light as disturbances in lines of force. Using our unified model, we show that such disturbances resemble photons: they are polarised, absorbed discretely, obey Maxwell's full equations of electromagnetism to first order, and quantitatively reproduce the correlation that is observed in the Bell tests.

  17. Piezoelectric step-motion actuator

    DOE Patents [OSTI]

    Mentesana; Charles P. (Leawood, KS)

    2006-10-10T23:59:59.000Z

    A step-motion actuator using piezoelectric material to launch a flight mass which, in turn, actuates a drive pawl to progressively engage and drive a toothed wheel or rod to accomplish stepped motion. Thus, the piezoelectric material converts electrical energy into kinetic energy of the mass, and the drive pawl and toothed wheel or rod convert the kinetic energy of the mass into the desired rotary or linear stepped motion. A compression frame may be secured about the piezoelectric element and adapted to pre-compress the piezoelectric material so as to reduce tensile loads thereon. A return spring may be used to return the mass to its resting position against the compression frame or piezoelectric material following launch. Alternative embodiment are possible, including an alternative first embodiment wherein two masses are launched in substantially different directions, and an alternative second embodiment wherein the mass is eliminated in favor of the piezoelectric material launching itself.

  18. Collective cyclotron motion of the relativistic plasma in graphene

    E-Print Network [OSTI]

    Markus Mueller; Subir Sachdev

    2008-09-19T23:59:59.000Z

    We present a theory of the finite temperature thermo-electric response functions of graphene, in the hydrodynamic regime induced by electron-electron collisions. In moderate magnetic fields, the Dirac particles undergo a collective cyclotron motion with a temperature-dependent relativistic cyclotron frequency proportional to the net charge density of the Dirac plasma. In contrast to the undamped cyclotron pole in Galilean-invariant systems (Kohn's theorem), here there is a finite damping induced by collisions between the counter-propagating particles and holes. This cyclotron motion shows up as a damped pole in the frequency dependent conductivities, and should be readily detectable in microwave measurements at room temperature. We also discuss the large Nernst effect to be expected in graphene.

  19. Perturbative renormalization of proton observables in lattice QCD using domain wall fermions

    E-Print Network [OSTI]

    Bistrović , Bojan

    2005-01-01T23:59:59.000Z

    Deep inelastic scattering unambiguously measures hadron observables characterizing the quark-gluon structure of hadrons. The only way to calculate these observables from first principles is lattice QCD. Experiments measure ...

  20. Exploration of the intrinsic inertial response of ferroelectric domain walls via molecular dynamics simulations

    E-Print Network [OSTI]

    Rappe, Andrew M.

    the measured dependence of impedance response on capacitor perimeter and theoretical predictions with a simple 10Ã?10 m, which is smaller than the lattice constant.11 Furthermore, recent in-situ investigations

  1. Nucleon axial charge from quenched lattice QCD with domain wall fermions and improved gauge action

    E-Print Network [OSTI]

    Shoichi Sasaki; Tom Blum; Shigemi Ohta; Kostas Orginos

    2001-10-12T23:59:59.000Z

    In our previous DWF calculation with the Wilson gauge action at $\\beta=6.0$ ($a^{-1}\\simeq$ 1.9 GeV) on a $16^3 \\times 32 \\times 16$ lattice, we found that $\\Ga$ had a fairly strong dependence on the quark mass. A simple linear extrapolation of $\\Ga$ to the chiral limit yielded a value that was almost a factor of two smaller than the experimental one. Here we report our recent study of this issue. In particular, we investigate possible errors arising from finite lattice volume, especially in the lighter quark mass region. We employ a RG-improved gauge action (DBW2), which maintains very good chiral behavior even on a coarse lattice ($a^{-1}\\simeq$ 1.3 GeV), in order to perform simulations at large physical volume ($> (2{\\rm fm})^3$). Our preliminary results suggest that the finite volume effect is significant.

  2. Visually simulating realistic fluid motion

    E-Print Network [OSTI]

    Naithani, Priyanka

    2002-01-01T23:59:59.000Z

    's second law of motion and Conservation of Mass, which leads to the continuity equation. Newton's second law states that the total force F, acting on an element equals mass m times the element's acceleration a. In the case of fluids we do not consider...

  3. 1 Introduction Synthetic motion capture

    E-Print Network [OSTI]

    Terzopoulos, Demetri

    animation of animals in virtual worlds, but at significant computational cost. Syn- thetic motion capture). Lifelike virtual animals naturally beckon active in- volvement, and one feels compelled to interact also form the basis of Miller's snakes and worms (Miller 1988), the virtual humans of Hodgins et al

  4. Smoothing of respiratory motion traces for motion-compensated radiotherapy

    SciTech Connect (OSTI)

    Ernst, Floris; Schlaefer, Alexander; Schweikard, Achim [Institute for Robotics and Cognitive Systems, University of Luebeck, Ratzeburger Allee 160, Luebeck SH 23538 (Germany)

    2010-01-15T23:59:59.000Z

    Purpose: The CyberKnife system has been used successfully for several years to radiosurgically treat tumors without the need for stereotactic fixation or sedation of the patient. It has been shown that tumor motion in the lung, liver, and pancreas can be tracked with acceptable accuracy and repeatability. However, highly precise targeting for tumors in the lower abdomen, especially for tumors which exhibit strong motion, remains problematic. Reasons for this are manifold, like the slow tracking system operating at 26.5 Hz, and using the signal from the tracking camera ''as is''. Since the motion recorded with the camera is used to compensate for system latency by prediction and the predicted signal is subsequently used to infer the tumor position from a correlation model based on x-ray imaging of gold fiducials around the tumor, camera noise directly influences the targeting accuracy. The goal of this work is to establish the suitability of a new smoothing method for respiratory motion traces used in motion-compensated radiotherapy. The authors endeavor to show that better prediction--With a lower rms error of the predicted signal--and/or smoother prediction is possible using this method. Methods: The authors evaluated six commercially available tracking systems (NDI Aurora, PolarisClassic, Polaris Vicra, MicronTracker2 H40, FP5000, and accuTrack compact). The authors first tracked markers both stationary and while in motion to establish the systems' noise characteristics. Then the authors applied a smoothing method based on the a trous wavelet decomposition to reduce the devices' noise level. Additionally, the smoothed signal of the moving target and a motion trace from actual human respiratory motion were subjected to prediction using the MULIN and the nLMS{sub 2} algorithms. Results: The authors established that the noise distribution for a static target is Gaussian and that when the probe is moved such as to mimic human respiration, it remains Gaussian with the exception of the FP5000 and the Aurora systems. The authors also showed that the proposed smoothing method can indeed be used to filter noise. The signal's jitter dropped by as much as 95% depending on the tracking system employed. Subsequently, the 3D prediction error (rms) for a prediction horizon of 150 ms on a synthetic signal dropped by up to 37% when using a normalized LMS prediction algorithm (nLMS{sub 2}) and hardly changed when using a MULIN algorithm. When smoothing a real signal obtained in our laboratory, the improvement of prediction was similar: Up to 30% for both the nLMS{sub 2} and the best MULIN algorithm. The authors also found a noticeable increase in smoothness of the predicted signal, the relative jitter dropped by up to 95% on the real signal, and on the simulated signal. Conclusions: In conclusion, the authors can say that preprocessing of marker data is very useful in motion-compensated radiotherapy since the quality of prediction increases. This will result in better performance of the correlation model. As a side effect, since the prediction of a preprocessed signal is also less noisy, the authors expect less robot vibration resulting in better targeting accuracy and less strain on the robot gears.

  5. Magnetically-actuated artificial cilia for microfluidic propulsion

    E-Print Network [OSTI]

    Khaderi, S N; Anderson, P D; Ioan, D; Toonder, J M J den; Onck, P R

    2009-01-01T23:59:59.000Z

    Natural cilia are hair-like microtubule-based structures that are able to move fluid at low Reynolds number through asymmetric motion. In this paper we follow a biomimetic approach to design artificial cilia lining the inner surface of microfluidic channels with the goal to propel fluid. The artificial cilia consist of polymer films filled with magnetic nanoparticles. The asymmetric, non-reciprocating motion is generated by tuning an external magnetic field. To obtain the magnetic field and associated magnetization local to the cilia we solve the Maxwell equations, from which the magnetic torques can be deduced. To obtain the ciliary motion we solve the dynamic equations of motion which are then fully coupled to the fluid dynamic equations that describe fluid flow around the cilia. By doing so we show that by properly tuning the applied magnetic field, asymmetric ciliary motion can be generated that is able to propel fluid in a microchannel. The results are presented in terms of three dimensionless parameters...

  6. TRACKING TONGUE MOTION IN THREE DIMENSIONS USING TAGGED MR IMAGES Xiaofeng Liu1

    E-Print Network [OSTI]

    Prince, Jerry L.

    TRACKING TONGUE MOTION IN THREE DIMENSIONS USING TAGGED MR IMAGES Xiaofeng Liu1 , Maureen Stone3 and strain analysis of tagged magnetic res- onance (MR) imaging [1]. It was originally applied to car- diac This research was supported by NIH grants R01 HL047405 and R01 DC001758 (a) (b) Fig. 1. (a) A tagged MR image

  7. Effect of Quantum Fluctuations on the Dipolar Motion of Bose-Einstein Condensates in Optical Lattices

    E-Print Network [OSTI]

    Wang, Daw-Wei

    Effect of Quantum Fluctuations on the Dipolar Motion of Bose-Einstein Condensates in Optical of condensate atoms in one-dimensional optical lattices and harmonic magnetic traps including quantum is reduced, on the contrary, strong quantum fluctuations lead to finite damping of condensate oscillations

  8. Large-scale molecular dynamics simulation of magnetic properties of amorphous iron under pressure

    E-Print Network [OSTI]

    ) Enhanced refrigerant capacity and magnetic entropy flattening using a two-amorphous FeZrB(Cu) compositeLarge-scale molecular dynamics simulation of magnetic properties of amorphous iron under pressure Appl. Phys. Lett. 99, 232501 (2011) Nonlinear motion of magnetic vortex under alternating

  9. Magnetic investigations

    SciTech Connect (OSTI)

    Bath, G.D.; Jahren, C.E.; Rosenbaum, J.G. [Geological Survey, Denver, CO (USA); Baldwin, M.J. [Fenix and Scisson, Inc., Mercury, NV (USA)

    1983-12-31T23:59:59.000Z

    Air and ground magnetic anomalies in the Climax stock area of the NTS help define the gross configuration of the stock and detailed configuration of magnetized rocks at the Boundary and Tippinip faults that border the stock. Magnetizations of geologic units were evaluated by measurements of magnetic properties of drill core, minimum estimates of magnetizations from ground magnetic anomalies for near surface rocks, and comparisons of measured anomalies with anomalies computed by a three-dimensional forward program. Alluvial deposits and most sedimentary rocks are nonmagnetic, but drill core measurements reveal large and irregular changes in magnetization for some quartzites and marbles. The magnetizations of quartz monzonite and granodiorite near the stock surface are weak, about 0.15 A/m, and increase at a rate of 0.00196 A/m/m to 1.55 A/m, at depths greater than 700 m (2300 ft). The volcanic rocks of the area are weakly magnetized. Aeromagnetic anomalies 850 m (2800 ft) above the stock are explained by a model consisting of five vertical prisms. Prisms 1, 2, and 3 represent the near surface outline of the stock, prism 4 is one of the models developed by Whitehill (1973), and prism 5 is modified from the model developed by Allingham and Zietz (1962). Most of the anomaly comes from unsampled and strongly-magnetized deep sources that could be either granite or metamorphosed sedimentary rocks. 48 refs., 23 figs., 3 tabs.

  10. Topology-based character motion synthesis 

    E-Print Network [OSTI]

    Ho, Shu Lim

    2011-06-30T23:59:59.000Z

    This thesis tackles the problem of automatically synthesizing motions of close-character interactions which appear in animations of wrestling and dancing. Designing such motions is a daunting task even for experienced ...

  11. Metrics for sampling-based motion planning 

    E-Print Network [OSTI]

    Morales Aguirre, Marco Antonio

    2009-05-15T23:59:59.000Z

    A motion planner finds a sequence of potential motions for a robot to transit from an initial to a goal state. To deal with the intractability of this problem, a class of methods known as sampling-based planners build ...

  12. Generalized Sampling-Based Feedback Motion Planners

    E-Print Network [OSTI]

    Kumar, Sandip

    2012-02-14T23:59:59.000Z

    The motion planning problem can be formulated as a Markov decision process (MDP), if the uncertainties in the robot motion and environments can be modeled probabilistically. The complexity of solving these MDPs grow exponentially as the dimension...

  13. Video looping of human cyclic motion

    E-Print Network [OSTI]

    Choi, Hye Mee

    2004-09-30T23:59:59.000Z

    In this thesis, a system called Video Looping is developed to analyze human cyclic motions. Video Looping allows users to extract human cyclic motion from a given video sequence. This system analyzes similarities from a large amount of live footage...

  14. Quantification of disturbance energy due to conductor motion and stability analysis of superconducting composite wire

    SciTech Connect (OSTI)

    Tsukamoto, O.; Takao, T.; Honjo, S.

    1989-03-01T23:59:59.000Z

    One of the most intricate disturbances causing quenches in high-current-density superconducting magnets is an abrupt conductor motion. There have been very few papers investigating the disturbance energy of the conductor motion and its generally understood that its quantification is very difficult. The authors have proposed a model to quantify the disturbance energy due to conductor motion. The model relates the disturbance energy to mechanical properties of a conductor, electromagnetic force and winding structure. In the paper, stability of a superconducting composite conductor subject to an abrupt conductor motion is analyzed based on the proposed model. It is pointed out that the stability of the conductor is improved by decreasing distance between spacers placed between the conductors. However, it is also pointed out that there is a limit to the improvement of the stability of decreasing the spacer distance, because of limited accuracies of the conductor and spacer dimensions.

  15. Optical analog of Rabi oscillation suppression due to atomic motion

    E-Print Network [OSTI]

    J. G. Muga; B. Navarro

    2005-05-13T23:59:59.000Z

    The Rabi oscillations of a two-level atom illuminated by a laser on resonance with the atomic transition may be suppressed by the atomic motion through averaging or filtering mechanisms. The optical analogs of these velocity effects are described. The two atomic levels correspond in the optical analogy to orthogonal polarizations of light and the Rabi oscillations to polarization oscillations in a medium which is optically active, naturally or due to a magnetic field. In the later case, the two orthogonal polarizations could be selected by choosing the orientation of the magnetic field, and one of them be filtered out. It is argued that the time-dependent optical polarization oscillations or their suppression are observable with current technology.

  16. Ground motion input in seismic evaluation studies

    SciTech Connect (OSTI)

    Sewell, R.T.; Wu, S.C.

    1996-07-01T23:59:59.000Z

    This report documents research pertaining to conservatism and variability in seismic risk estimates. Specifically, it examines whether or not artificial motions produce unrealistic evaluation demands, i.e., demands significantly inconsistent with those expected from real earthquake motions. To study these issues, two types of artificial motions are considered: (a) motions with smooth response spectra, and (b) motions with realistic variations in spectral amplitude across vibration frequency. For both types of artificial motion, time histories are generated to match target spectral shapes. For comparison, empirical motions representative of those that might result from strong earthquakes in the Eastern U.S. are also considered. The study findings suggest that artificial motions resulting from typical simulation approaches (aimed at matching a given target spectrum) are generally adequate and appropriate in representing the peak-response demands that may be induced in linear structures and equipment responding to real earthquake motions. Also, given similar input Fourier energies at high-frequencies, levels of input Fourier energy at low frequencies observed for artificial motions are substantially similar to those levels noted in real earthquake motions. In addition, the study reveals specific problems resulting from the application of Western U.S. type motions for seismic evaluation of Eastern U.S. nuclear power plants.

  17. Flow and Plate Motion in Compressor Valves

    E-Print Network [OSTI]

    Twente, Universiteit

    Flow and Plate Motion in Compressor Valves #12;Flow and Plate Motion in Compressor Valves R.A. Habing Cover Image: 4-stage reciprocating compressor system, Courtesy of Ariel Corporation Thesis.A. Habing, Enschede, The Netherlands #12;FLOW AND PLATE MOTION IN COMPRESSOR VALVES PROEFSCHRIFT ter

  18. Learning Motion Style Synthesis from Perceptual Observations

    E-Print Network [OSTI]

    Bregler, Christoph

    that the learned model can apply a variety of motion styles to pre-recorded motion sequences and it can extrapolate models that are unable to fully capture the subtleties and complexities of human movement based on learned parametric models. The aim is to maintain the animated preci- sion of motion capture

  19. Magnetic Field Safety Magnetic Field Safety

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Magnetic Field Safety Training #12;Magnetic Field Safety Strong Magnetic Fields exist around energized magnets. High magnetic fields alone are a recognized hazard only for personnel with certain medical conditions such as pacemakers, magnetic implants, or embedded shrapnel. In addition, high magnetic

  20. Energy Conservation Equations of Motion

    E-Print Network [OSTI]

    Vinokurov, Nikolay A

    2015-01-01T23:59:59.000Z

    A conventional derivation of motion equations in mechanics and field equations in field theory is based on the principle of least action with a proper Lagrangian. With a time-independent Lagrangian, a function of coordinates and velocities that is called energy is constant. This paper presents an alternative approach, namely derivation of a general form of equations of motion that keep the system energy, expressed as a function of generalized coordinates and corresponding velocities, constant. These are Lagrange equations with addition of gyroscopic forces. The important fact, that the energy is defined as the function on the tangent bundle of configuration manifold, is used explicitly for the derivation. The Lagrangian is derived from a known energy function. A development of generalized Hamilton and Lagrange equations without the use of variational principles is proposed. The use of new technique is applied to derivation of some equations.

  1. Strange Magnetism

    E-Print Network [OSTI]

    Thomas R. Hemmert; Ulf-G. Meissner; Sven Steininger

    1998-11-09T23:59:59.000Z

    We present an analytic and parameter-free expression for the momentum dependence of the strange magnetic form factor of the nucleon and its corresponding radius which has been derived in Heavy Baryon Chiral Perturbation Theory. We also discuss a model-independent relation between the isoscalar magnetic and the strange magnetic form factors of the nucleon based on chiral symmetry and SU(3) only. These limites are used to derive bounds on the strange magnetic moment of the proton from the recent measurement by the SAMPLE collaboration.

  2. Relativistic Motion with Superconducting Qubits

    E-Print Network [OSTI]

    Felicetti, S; Fuentes, I; Lamata, L; Romero, G; Solano, E

    2015-01-01T23:59:59.000Z

    We show how the dynamical modulation of the qubit-field coupling strength in a circuit quantum electrodynamics architecture mimics the motion of the qubit at relativistic speeds. This allows us to propose a realistic experiment to detect microwave photons coming from simulated acceleration radiation. Moreover, by combining this technique with the dynamical Casimir physics, we enhance the toolbox for studying relativistic phenomena in quantum field theory with superconducting circuits.

  3. A Randomized Controlled Trial of Lorazepam to Reduce Liver Motion in Patients Receiving Upper Abdominal Radiation Therapy

    SciTech Connect (OSTI)

    Tsang, Derek S.; Voncken, Francine E.M.; Tse, Regina V. [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Sykes, Jenna [Department of Biostatistics, Princess Margaret Cancer Centre, University Health Network, Toronto (Canada); Wong, Rebecca K.S.; Dinniwell, Rob E.; Kim, John; Ringash, Jolie; Brierley, James D.; Cummings, Bernard J.; Brade, Anthony [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Dawson, Laura A., E-mail: laura.dawson@rmp.uhn.on.ca [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada)

    2013-12-01T23:59:59.000Z

    Purpose: Reduction of respiratory motion is desirable to reduce the volume of normal tissues irradiated, to improve concordance of planned and delivered doses, and to improve image guided radiation therapy (IGRT). We hypothesized that pretreatment lorazepam would lead to a measurable reduction of liver motion. Methods and Materials: Thirty-three patients receiving upper abdominal IGRT were recruited to a double-blinded randomized controlled crossover trial. Patients were randomized to 1 of 2 study arms: arm 1 received lorazepam 2 mg by mouth on day 1, followed by placebo 4 to 8 days later; arm 2 received placebo on day 1, followed by lorazepam 4 to 8 days later. After tablet ingestion and daily radiation therapy, amplitude of liver motion was measured on both study days. The primary outcomes were reduction in craniocaudal (CC) liver motion using 4-dimensional kV cone beam computed tomography (CBCT) and the proportion of patients with liver motion ?5 mm. Secondary endpoints included motion measured with cine magnetic resonance imaging and kV fluoroscopy. Results: Mean relative and absolute reduction in CC amplitude with lorazepam was 21% and 2.5 mm respectively (95% confidence interval [CI] 1.1-3.9, P=.001), as assessed with CBCT. Reduction in CC amplitude to ?5 mm residual liver motion was seen in 13% (95% CI 1%-25%) of patients receiving lorazepam (vs 10% receiving placebo, P=NS); 65% (95% CI 48%-81%) had reduction in residual CC liver motion to ?10 mm (vs 52% with placebo, P=NS). Patients with large respiratory movement and patients who took lorazepam ?60 minutes before imaging had greater reductions in liver CC motion. Mean reductions in liver CC amplitude on magnetic resonance imaging and fluoroscopy were nonsignificant. Conclusions: Lorazepam reduces liver motion in the CC direction; however, average magnitude of reduction is small, and most patients have residual motion >5 mm.

  4. RHIC stochastic cooling motion control

    SciTech Connect (OSTI)

    Gassner, D.; DeSanto, L.; Olsen, R.H.; Fu, W.; Brennan, J.M.; Liaw, CJ; Bellavia, S.; Brodowski, J.

    2011-03-28T23:59:59.000Z

    Relativistic Heavy Ion Collider (RHIC) beams are subject to Intra-Beam Scattering (IBS) that causes an emittance growth in all three-phase space planes. The only way to increase integrated luminosity is to counteract IBS with cooling during RHIC stores. A stochastic cooling system for this purpose has been developed, it includes moveable pick-ups and kickers in the collider that require precise motion control mechanics, drives and controllers. Since these moving parts can limit the beam path aperture, accuracy and reliability is important. Servo, stepper, and DC motors are used to provide actuation solutions for position control. The choice of motion stage, drive motor type, and controls are based on needs defined by the variety of mechanical specifications, the unique performance requirements, and the special needs required for remote operations in an accelerator environment. In this report we will describe the remote motion control related beam line hardware, position transducers, rack electronics, and software developed for the RHIC stochastic cooling pick-ups and kickers.

  5. Absolute Motion and Gravitational Effects

    E-Print Network [OSTI]

    Cahill, R T

    2003-01-01T23:59:59.000Z

    The new Process Physics provides a new explanation of space as a quantum foam system in which gravity is an inhomogeneous flow of the quantum foam into matter. An analysis of various experiments demonstrates that absolute motion relative to space has been observed experimentally by Michelson and Morley, Miller, Illingworth, Torr and Kolen, and by DeWitte. The Dayton Miller and Roland DeWitte data also reveal the in-flow of space into matter which manifests as gravity. The in-flow also manifests turbulence and the experimental data confirms this as well, which amounts to the observation of a gravitational wave phenomena. The Einstein assumptions leading to the Special and General Theory of Relativity are shown to be falsified by the extensive experimental data. Contrary to the Einstein assumptions absolute motion is consistent with relativistic effects, which are caused by actual dynamical effects of absolute motion through the quantum foam, so that it is Lorentzian relativity that is seen to be essentially co...

  6. Absolute Motion and Gravitational Effects

    E-Print Network [OSTI]

    Reginald T Cahill

    2003-06-29T23:59:59.000Z

    The new Process Physics provides a new explanation of space as a quantum foam system in which gravity is an inhomogeneous flow of the quantum foam into matter. An analysis of various experiments demonstrates that absolute motion relative to space has been observed experimentally by Michelson and Morley, Miller, Illingworth, Torr and Kolen, and by DeWitte. The Dayton Miller and Roland DeWitte data also reveal the in-flow of space into matter which manifests as gravity. The in-flow also manifests turbulence and the experimental data confirms this as well, which amounts to the observation of a gravitational wave phenomena. The Einstein assumptions leading to the Special and General Theory of Relativity are shown to be falsified by the extensive experimental data. Contrary to the Einstein assumptions absolute motion is consistent with relativistic effects, which are caused by actual dynamical effects of absolute motion through the quantum foam, so that it is Lorentzian relativity that is seen to be essentially correct.

  7. The transverse and rotational motions of magnetohydrodynamic kink waves in the solar atmosphere

    SciTech Connect (OSTI)

    Goossens, M.; Van Doorsselaere, T. [Centre for Mathematical Plasma Astrophysics, Katholieke Universiteit Leuven, Celestijnenlaan 200B, bus 2400, B-3001 Herverlee (Belgium); Soler, R.; Terradas, J. [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Verth, G., E-mail: marcel.goossens@wis.kuleuven.be [Solar Physics and Space Plasma Research Centre (SP2RC), The University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

    2014-06-10T23:59:59.000Z

    Magnetohydrodynamic (MHD) kink waves have now been observed to be ubiquitous throughout the solar atmosphere. With modern instruments, they have now been detected in the chromosphere, interface region, and corona. The key purpose of this paper is to show that kink waves do not only involve purely transverse motions of solar magnetic flux tubes, but the velocity field is a spatially and temporally varying sum of both transverse and rotational motion. Taking this fact into account is particularly important for the accurate interpretation of varying Doppler velocity profiles across oscillating structures such as spicules. It has now been shown that, as well as bulk transverse motions, spicules have omnipresent rotational motions. Here we emphasize that caution should be used before interpreting the particular MHD wave mode/s responsible for these rotational motions. The rotational motions are not necessarily signatures of the classic axisymmetric torsional Alfvén wave alone, because kink motion itself can also contribute substantially to varying Doppler velocity profiles observed across these structures. In this paper, the displacement field of the kink wave is demonstrated to be a sum of its transverse and rotational components, both for a flux tube with a discontinuous density profile at its boundary, and one with a more realistic density continuum between the internal and external plasma. Furthermore, the Doppler velocity profile of the kink wave is forward modeled to demonstrate that, depending on the line of sight, it can either be quite distinct or very similar to that expected from a torsional Alfvén wave.

  8. Generation of the magnetic field in jets

    E-Print Network [OSTI]

    V. Urpin

    2006-05-22T23:59:59.000Z

    We consider dynamo action under the combined influence of turbulence and large-scale shear in sheared jets. Shear can stretch turbulent magnetic field lines in such a way that even turbulent motions showing mirror symmetry become suitable for generation of a large-scale magnetic field. We derive the integral induction equation governing the behaviour of the mean field in jets. The main result is that sheared jets may generate a large-scale magnetic field if shear is sufficiently strong. The generated mean field is mainly concentrated in a magnetic sheath surrounding the central region of a jet, and it exhibits sign reversals in the direction of the jet axis. Typically, the magnetic field in a sheath is dominated by the component along the jet that can reach equipartition with the kinetic energy of particles, The field in the central region of jets has a more disordered structure.

  9. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, R.F.

    1998-03-03T23:59:59.000Z

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds. 7 figs.

  10. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    1998-01-01T23:59:59.000Z

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds.

  11. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, J.A.; Stone, R.R.; Fabyan, J.

    1985-02-12T23:59:59.000Z

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

  12. Magnetic changes observed in a solar flare

    SciTech Connect (OSTI)

    Moore, R.L.; Hurford, G.J.; Jones, H.P.; Kane, S.R.

    1984-01-01T23:59:59.000Z

    We present observations of a fairly large impulsive flare (1B/M4, starting 17:22 UT, 1980 April 10). Observations of the microwave/hard X-ray burst show the time development of the impulsive energy release. Chromospheric (H..cap alpha..) and photospheric (Fe I lambda5324) filtergrams and photospheric (Fe I lambda8688) magnetograms, intensitygrams, and velocitygrams show magnetic strucutre, flare emission, mass motion, and magnetic changes. From these observations, we conclude: 1. The flare was triggered by a small emerging magnetic bipole. 2. The peak impulsive energy release occurred in the explosive eruption of a filament from over the magnetic inversion line. Hence: a) The filament eruption was the magnetic transient in the heart of the primary energy release in the chromosphere and corona. b) The primary energy release did not occur in approximately stationary magnetic loops, but on field lines undergoing violet motion and drastic changes in direction. 3. In the photospheric magnetograph lines. Fe I lambda5324 and Fe I lambda8688, the impulsive peak of the flare produced emission in a unipolar area of a sunspot. In synchrony with the emission, the polarity of this area transiently reversed in the lambda8688 magnetigrams; apparently, this was an artifact of the line emission. 4. Within a few minutes after the explosive filament eruption. a) A permanent decrease in magnetic flux accompanied the truncation of an umbra. b) A permanent increase in magnetic flux accompanied the severance of the penumbral bridge to a satellite sunspot. Apparently, thee genuine photospheric magnetic changes were consequences of strong flare-wrought magnetic changes in the chromospher and corona.

  13. Magnetic nanotubes

    DOE Patents [OSTI]

    Matsui, Hiroshi (Glen Rock, NJ); Matsunaga, Tadashi (Tokyo, JP)

    2010-11-16T23:59:59.000Z

    A magnetic nanotube includes bacterial magnetic nanocrystals contacted onto a nanotube which absorbs the nanocrystals. The nanocrystals are contacted on at least one surface of the nanotube. A method of fabricating a magnetic nanotube includes synthesizing the bacterial magnetic nanocrystals, which have an outer layer of proteins. A nanotube provided is capable of absorbing the nanocrystals and contacting the nanotube with the nanocrystals. The nanotube is preferably a peptide bolaamphiphile. A nanotube solution and a nanocrystal solution including a buffer and a concentration of nanocrystals are mixed. The concentration of nanocrystals is optimized, resulting in a nanocrystal to nanotube ratio for which bacterial magnetic nanocrystals are immobilized on at least one surface of the nanotubes. The ratio controls whether the nanocrystals bind only to the interior or to the exterior surfaces of the nanotubes. Uses include cell manipulation and separation, biological assay, enzyme recovery, and biosensors.

  14. Magnets & Magnet Condensed Matter Science

    E-Print Network [OSTI]

    McQuade, D. Tyler

    18 No. 1 CONDENSED MATTER SCIENCE Technique development, graphene, magnetism & magnetic materials Pressure 9 Metal to Insulator Transition on the N=0 Landau Level in Graphene 10 Evidence for Fractional Quantum Hall States in Suspended Bilayer and Trilayer Graphene 11 Fractional Quantum Hall Effect

  15. Approaches to Creating and Controlling Motion in MRI Gregory S. Fischer, Member, IEEE, Gregory Cole, Student Member, IEEE and Hao Su, Student Member, IEEE

    E-Print Network [OSTI]

    Camesano, Terri

    Approaches to Creating and Controlling Motion in MRI Gregory S. Fischer, Member, IEEE, Gregory Cole, Student Member, IEEE and Hao Su, Student Member, IEEE Abstract-- Magnetic Resonance Imaging (MRI) can is complicated by factors including: the high magnetic field strength, the requirement that such devices should

  16. Development of a 6-degree-of-freedom magnetically levitated instrument with nanometer precision 

    E-Print Network [OSTI]

    Gu, Jie

    2004-09-30T23:59:59.000Z

    This thesis presents the design and fabrication of a novel magnetically levitated (maglev) device with six-degree-of-freedom motion capability at nanometer precision. The applications of this device are manufacture of ...

  17. Low dimensional magnetism

    E-Print Network [OSTI]

    Kjall, Jonas Alexander

    2012-01-01T23:59:59.000Z

    Magnetism in Ultracold Gases 4 Magnetic phase diagram of aMagnetism . . . . . . . . . . . .1.3 Magnetism in condensedIntroduction 1 Brief introduction to magnetism 1.1 Classic

  18. Hydrogen Atom in Relativistic Motion

    E-Print Network [OSTI]

    M. Jarvinen

    2005-04-11T23:59:59.000Z

    The Lorentz contraction of bound states in field theory is often appealed to in qualitative descriptions of high energy particle collisions. Surprisingly, the contraction has not been demonstrated explicitly even in simple cases such as the hydrogen atom. It requires a calculation of wave functions evaluated at equal (ordinary) time for bound states in motion. Such wave functions are not obtained by kinematic boosts from the rest frame. Starting from the exact Bethe-Salpeter equation we derive the equal-time wave function of a fermion-antifermion bound state in QED, i.e., positronium or the hydrogen atom, in any frame to leading order in alpha. We show explicitly that the bound state energy transforms as the fourth component of a vector and that the wave function of the fermion-antifermion Fock state contracts as expected. Transverse photon exchange contributes at leading order to the binding energy of the bound state in motion. We study the general features of the corresponding fermion-antifermion-photon Fock states, and show that they do not transform by simply contracting. We verify that the wave function reduces to the light-front one in the infinite momentum frame.

  19. Controlling Magnetism at the Nanoscale

    E-Print Network [OSTI]

    Wong, Jared

    2012-01-01T23:59:59.000Z

    Manipulation of Magnetism - External148 Conclusion A The Magnetism Cheat Sheet A.1 Magnetic157 A.2 Magnetism Unit Conversion

  20. The National High Magnetic Field Laboratory was represented by staff from its Center for Integrating Research and Learning

    E-Print Network [OSTI]

    McQuade, D. Tyler

    to drop a magnet seemingly in slow motion through a copper pipe. The USA Science and Engineering Festival and Engineering Festival National High Magnetic Field Laboratory Funding Grants: G.S. Boebinger (NSF DMR-1157490The National High Magnetic Field Laboratory was represented by staff from its Center

  1. Computing Vortex Sheet Motion Robert Krasny

    E-Print Network [OSTI]

    Krasny, Robert

    Computing Vortex Sheet Motion Robert Krasny Department of Mathematics, University of Michigan, Ann;1574 Robert Krasny with respect to the time variable and obtained results consistent with Moore

  2. Neutrino magnetic moment in a magnetized plasma

    E-Print Network [OSTI]

    N. V. Mikheev; E. N. Narynskaya

    2010-11-08T23:59:59.000Z

    The contribution of a magnetized plasma to the neutrino magnetic moment is calculated. It is shown that only part of the additional neutrino energy in magnetized plasma connecting with its spin and magnetic field strength defines the neutrino magnetic moment. It is found that the presence of magnetized plasma does not lead to the considerable increase of the neutrino magnetic moment in contrast to the results presented in literature previously.

  3. Cross-fixation transfer of motion aftereffects with expansion motion Xin Meng a,1

    E-Print Network [OSTI]

    Columbia University

    by expanding random-dots stimuli. We also used rightward translational motion for comparison. Subjects adapted, a test pattern without net motion elicits more response in the opposite direction than the adapted

  4. Noninvasive valve monitor using constant magnetic and/or DC electromagnetic field

    DOE Patents [OSTI]

    Casada, Donald A. (Knoxville, TN); Haynes, Howard D. (Knoxville, TN)

    1993-01-01T23:59:59.000Z

    One or more sources of steady magnetic field are carefully located on the outside of a valve body. The constant magnetic field is transmitted into the valve body and valve internals. A magnetic field detector carefully located on the outside of the valve body detects the intensity of the magnetic field at its location. As the position of a valve internal part is changed, there is an alteration in the magnetic field in the valve, and a consequent change in the detected magnetic field. Changes in the detected signal provide an indication of the position and motion of the valve internals.

  5. Magnetic monopole field exposed by electrons

    E-Print Network [OSTI]

    Béché, A; Van Tendeloo, G; Verbeeck, J

    2013-01-01T23:59:59.000Z

    Magnetic monopoles have provided a rich field of study, leading to a wide area of research in particle physics, solid state physics, ultra-cold gases, superconductors, cosmology, and gauge theory. So far, no true magnetic monopoles were found experimentally. Using the Aharonov-Bohm effect, one of the central results of quantum physics, shows however, that an effective monopole field can be produced. Understanding the effects of such a monopole field on its surroundings is crucial to its observation and provides a better grasp of fundamental physical theory. We realize the diffraction of fast electrons at a magnetic monopole field generated by a nanoscopic magnetized ferromagnetic needle. Previous studies have been limited to theoretical semiclassical optical calculations of the motion of electrons in such a monopole field. Solid state systems like the recently studied 'spin ice' provide a constrained system to study similar fields, but make it impossible to separate the monopole from the material. Free space ...

  6. NAAP Motions of the Sun 1/7 Motions of the Sun Student Guide

    E-Print Network [OSTI]

    Farritor, Shane

    Name: NAAP ­ Motions of the Sun 1/7 Motions of the Sun ­ Student Guide Seasonal Motion Work through in these pages are used in the Paths of the Sun Simulator. Question 1: For each of the following statements questions. (A) On May 25th , the sun is in the constellation of ___________________. (B) What would

  7. Petroglyphs, Lighting, and Magnetism

    E-Print Network [OSTI]

    Walker, Merle F

    2007-01-01T23:59:59.000Z

    1950 Electricity and Magnetism: Theory and Applications.I Petroglyphs, Lightning, and Magnetism | Walker Figure 8.I Petroglyphs, Lightning, and Magnetism | Walker Figure IL

  8. Helical motion and the origin of QPO in blazar-type sources

    E-Print Network [OSTI]

    Frank M. Rieger

    2004-10-22T23:59:59.000Z

    Recent observations and analysis of blazar sources provide strong evidence for (i) the presence of significant periodicities in their lightcurves and (ii) the occurrence of helical trajectories in their radio jets. In scenarios, where the periodicity is caused by differential Doppler boosting effects along a helical jet path, both of these facts may be naturally tied together. Here we discuss four possible driving mechanisms for the occurrence of helical trajectories: orbital motion in a binary system, Newtonian-driven jet precession, internal jet rotation and motion along a global helical magnetic field. We point out that for non-ballistic helical motion the observed period may appear strongly shortened due to classical travel time effects. Finally, the possible relevance of the above mentioned driving mechanisms is discussed for Mkn~501, OJ 287 and AO 0235+16.

  9. Electromagnetic Radiation and Motion of Real Particle

    E-Print Network [OSTI]

    Jozef Klacka

    2001-06-21T23:59:59.000Z

    Relativistically covariant equation of motion for real dust particle under the action of electromagnetic radiation is derived. The particle is neutral in charge. Equation of motion is expressed in terms of particle's optical properties, standardly used in optics for stationary particles.

  10. Roadmapbased Motion Planning in Dynamic Environments

    E-Print Network [OSTI]

    Utrecht, Universiteit

    Roadmap­based Motion Planning in Dynamic Environments Jur P. van den Berg Mark H. Overmars.cs.uu.nl #12; Roadmap­based Motion Planning in Dynamic Environments Jur P. van den Berg Mark H. Overmars April obstacles. We propose a practical algorithm based on a roadmap that is created for the static part

  11. Robot Motion Planning with Uncertainty The Challenge

    E-Print Network [OSTI]

    Whitton, Mary C.

    Roadmap (SMR), a new motion planning framework that explicitly considers uncertainty in robot motion approach. Our framework builds on the highly successful approach used in Probabilistic Roadmaps (PRMs of discrete states is selected in the state space, and a roadmap is built that represents their collision

  12. Metrics for sampling-based motion planning

    E-Print Network [OSTI]

    Morales Aguirre, Marco Antonio

    2009-05-15T23:59:59.000Z

    A motion planner finds a sequence of potential motions for a robot to transit from an initial to a goal state. To deal with the intractability of this problem, a class of methods known as sampling-based planners build approximate representations...

  13. The apsidal motion in close binary stars

    E-Print Network [OSTI]

    B. V. Vasiliev

    2001-10-10T23:59:59.000Z

    It is usually accepted to consider an apsidal motion in binary stars as a direct confirmation that a substance inside stars is not uniformly distributed. It is shown in this paper that the apsidal motion in binary systems observation data is in a good agreement with an existence of uniform plasma cores inside stars if they consist of hydrogen-deuterium-helium mixture.

  14. Seismic switch for strong motion measurement

    DOE Patents [OSTI]

    Harben, Philip E. (Oakley, CA); Rodgers, Peter W. (Santa Barbara, CA); Ewert, Daniel W. (Patterson, CA)

    1995-01-01T23:59:59.000Z

    A seismic switching device that has an input signal from an existing microseismic station seismometer and a signal from a strong motion measuring instrument. The seismic switch monitors the signal level of the strong motion instrument and passes the seismometer signal to the station data telemetry and recording systems. When the strong motion instrument signal level exceeds a user set threshold level, the seismometer signal is switched out and the strong motion signal is passed to the telemetry system. The amount of time the strong motion signal is passed before switching back to the seismometer signal is user controlled between 1 and 15 seconds. If the threshold level is exceeded during a switch time period, the length of time is extended from that instant by one user set time period.

  15. Seismic switch for strong motion measurement

    DOE Patents [OSTI]

    Harben, P.E.; Rodgers, P.W.; Ewert, D.W.

    1995-05-30T23:59:59.000Z

    A seismic switching device is described that has an input signal from an existing microseismic station seismometer and a signal from a strong motion measuring instrument. The seismic switch monitors the signal level of the strong motion instrument and passes the seismometer signal to the station data telemetry and recording systems. When the strong motion instrument signal level exceeds a user set threshold level, the seismometer signal is switched out and the strong motion signal is passed to the telemetry system. The amount of time the strong motion signal is passed before switching back to the seismometer signal is user controlled between 1 and 15 seconds. If the threshold level is exceeded during a switch time period, the length of time is extended from that instant by one user set time period. 11 figs.

  16. Controlling the magnetization reversal in exchange-biased Co/CoO elongated nanorings This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Adeyeye, Adekunle

    of Western Australia, Crawley, WA 6009, Australia E-mail: eleaao@nus.edu.sg Received 15 September 2008 head-on (180 ) domain walls [2]. Due to elimination of the high energy vortex core, the vortex state

  17. Impact of motion along the field direction on geometric-phase-induced false electric dipole moment signals

    E-Print Network [OSTI]

    H. Yan; B. Plaster

    2011-04-07T23:59:59.000Z

    Geometric-phase-induced false electric dipole moment (EDM) signals, resulting from interference between magnetic field gradients and particle motion in electric fields, have been studied extensively in the literature, especially for neutron EDM experiments utilizing stored ultracold neutrons and co-magnetometer atoms. Previous studies have considered particle motion in the transverse plane perpendicular to the direction of the applied electric and magnetic fields. We show, via Monte Carlo studies, that motion along the field direction can impact the magnitude of this false EDM signal if the wall surfaces are rough such that the wall collisions can be modeled as diffuse, with the results dependent on the size of the storage cell's dimension along the field direction.

  18. Magnetic Catalysis vs Magnetic Inhibition

    E-Print Network [OSTI]

    Kenji Fukushima; Yoshimasa Hidaka

    2012-09-06T23:59:59.000Z

    We discuss the fate of chiral symmetry in an extremely strong magnetic field B. We investigate not only quark fluctuations but also neutral meson effects. The former would enhance the chiral-symmetry breaking at finite B according to the Magnetic Catalysis, while the latter would suppress the chiral condensate once B exceeds the scale of the hadron structure. Using a chiral model we demonstrate how neutral mesons are subject to the dimensional reduction and the low dimensionality favors the chiral-symmetric phase. We point out that this effect, the Magnetic Inhibition, can be a feasible explanation for recent lattice-QCD data indicating the decreasing behavior of the chiral-restoration temperature with increasing B.

  19. Magnetic Stereoscopy

    E-Print Network [OSTI]

    Thomas Wiegelmann; Bernd Inhester

    2006-12-21T23:59:59.000Z

    The space mission STEREO will provide images from two viewpoints. An important aim of the STEREO mission is to get a 3D view of the solar corona. We develop a program for the stereoscopic reconstruction of 3D coronal loops from images taken with the two STEREO spacecraft. A pure geometric triangulation of coronal features leads to ambiguities because the dilute plasma emissions complicates the association of features in image 1 with features in image 2. As a consequence of these problems the stereoscopic reconstruction is not unique and multiple solutions occur. We demonstrate how these ambiguities can be resolved with the help of different coronal magnetic field models (potential, linear and non-linear force-free fields). The idea is that, due to the high conductivity in the coronal plasma, the emitting plasma outlines the magnetic field lines. Consequently the 3D coronal magnetic field provides a proxy for the stereoscopy which allows to eliminate inconsistent configurations. The combination of stereoscopy and magnetic modelling is more powerful than one of these tools alone. We test our method with the help of a model active region and plan to apply it to the solar case as soon as STEREO data become available.

  20. Superconducting Magnet Division

    E-Print Network [OSTI]

    Superconducting Magnet Division DOE NP Program Review - July 06 1 Brookhaven Magnet Division - Nuclear Physics Program Support Activities Superconducting Magnet Program RHIC Operations Support Spin Summary Peter Wanderer, DOE review, July 25, 2006 Acting Head, Superconducting Magnet Division #12

  1. Raman spectroscopy on surfacted ferrofluids in a magnetic field J. E. Weber,1

    E-Print Network [OSTI]

    Nabben, Reinhard

    a magnetic excitation with an intensity growing in proportion to the magnetization of the ferrofluid becomes of counteracting in- teractions. On one hand, thermal motion and electrostatic or surfactant-mediated repulsion scatter- ing in general and Raman spectroscopy in particular are a very powerful and sensitive tool

  2. Bipolar magnetic structures driven by stratified turbulence with a coronal Jorn Warnecke1,2

    E-Print Network [OSTI]

    Brandenburg, Axel

    is also an ingredient in some dynamo theories to explain the 22-year cyclic behavior of the solar magnetic motions. There- fore, sunspots appear dark on the solar disk. We are nowadays able to study them with high #12;­ 2 ­ Fig. 1.-- Left panel: normalized vertical magnetic field Bz/Beq of the bipolar region

  3. Slow motion responses of compliant offshore structures

    E-Print Network [OSTI]

    Cao, Peimin

    1996-01-01T23:59:59.000Z

    -HEAVE-PITCH MOTION ANALYSIS 3. 1 Mathematical Formulation . 3. 1. 1 Governing equation for surge-heave-pitch motions 3. 1. 2 Numerical scheme 3. 2 Comparisons of the JIP Spar . 3. 2. 1 Experimental set-up 3. 2. 2 Regular wave 3. 2. 3 Irregular wave 3. 2. 4... structural analyses. Courtesy of American Petroleum Institute. SDOF surge motion model of the JIP Spar. S?rge static offset test of the JIP Spar in the calm water. Surge RAOs of the JIP Spar: experiment ( ~ ); present ( ? ? ); and HOBEM ( ? - ? ). 14...

  4. A model of ATL ground motion for storage rings

    E-Print Network [OSTI]

    Wolski, Andrzej; Walker, Nicholas J.

    2003-01-01T23:59:59.000Z

    A MODEL OF ATL GROUND MOTION FOR STORAGE RINGS A. WolskiMODEL OF ATL GROUND MOTION FOR STORAGE RINGS* A. Wolski # ,

  5. advanced motion control: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    25 MARCH 2012 | DOI: 10.1038NPHYS2269 Attosecond control of collective electron motion Materials Science Websites Summary: electron motion in plasmas Antonin Borot1 , Arnaud...

  6. Effects of Seismic Motion Incoherency on SSI and SSSI Responses...

    Office of Environmental Management (EM)

    Effects of Seismic Motion Incoherency on SSI and SSSI Responses of Nuclear Structures for Different Soil Site Conditions Effects of Seismic Motion Incoherency on SSI and SSSI...

  7. Hydrogen Species Motion in Piezoelectrics: A Quasi-Elastic Neutron...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Species Motion in Piezoelectrics: A Quasi-Elastic Neutron Scattering Study. Hydrogen Species Motion in Piezoelectrics: A Quasi-Elastic Neutron Scattering Study. Abstract: Hydrogen...

  8. Neutrinoless double beta decay mediated by the neutrino magnetic moment

    E-Print Network [OSTI]

    Gó?d?, Marek

    2014-01-01T23:59:59.000Z

    We present a new channel of the neutrinoless double beta decay. In this scenario neutrinos not only oscillate inside the nucleus but also interact with an external non-uniform magnetic field. We assume that the field rotates about the direction of motion of the neutrino and show, that for a certain speed of rotation the half-life of the $0\

  9. Neutrinoless double beta decay mediated by the neutrino magnetic moment

    E-Print Network [OSTI]

    Marek Gó?d?; Wies?aw A. Kami?ski

    2014-11-07T23:59:59.000Z

    We present a new channel of the neutrinoless double beta decay. In this scenario neutrinos not only oscillate inside the nucleus but also interact with an external non-uniform magnetic field. We assume that the field rotates about the direction of motion of the neutrino and show, that for a certain speed of rotation the half-life of the $0\

  10. Test particle motion in modified gravity theories

    E-Print Network [OSTI]

    Mahmood Roshan

    2013-02-05T23:59:59.000Z

    We derive the equations of motion of an electrically neutral test particle for modified gravity theories in which the covariant divergence of the ordinary matter energy-momentum tensor dose not vanish (i.e. $\

  11. Information Fusion for Improved Motion Estimation 

    E-Print Network [OSTI]

    Peacock, Andrew M

    Motion Estimation is an important research field with many commercial applications including surveillance, navigation, robotics, and image compression. As a result, the field has received a great deal of attention and ...

  12. On learning task-directed motion plans

    E-Print Network [OSTI]

    Finney, Sarah, 1974-

    2009-01-01T23:59:59.000Z

    Robotic motion planning is a hard problem for robots with more than just a few degrees of freedom. Modern probabilistic planners are able to solve many problems very quickly, but for difficult problems, they are still ...

  13. The Design of Shape from Motion Constraints

    E-Print Network [OSTI]

    Caine, Michael E.

    1993-09-01T23:59:59.000Z

    This report presents a set of representations methodologies and tools for the purpose of visualizing, analyzing and designing functional shapes in terms of constraints on motion. The core of the research is an interactive ...

  14. DYNAMIC CHARACTERISTICSOFLIQUID MOTION INPARTIALLYFILLEDTANKS OF SPINNING SPACECRAFT

    E-Print Network [OSTI]

    . I. Introduction A recent trend in geosynchronousspacecraft design is using liquid apogee motors. In these spacecraft, liquid motion significantly influence the spacecraft attitude stability and control. LEASAT, a geosynchronous spacecraft with liquid apogee motor, launched in September 1984, experienced attitudecontrol

  15. Magnetic Reconnection

    SciTech Connect (OSTI)

    Masaaki Yamada, Russell Kulsrud and Hantao Ji

    2009-09-17T23:59:59.000Z

    We review the fundamental physics of magnetic reconnection in laboratory and space plasmas, by discussing results from theory, numerical simulations, observations from space satellites, and the recent results from laboratory plasma experiments. After a brief review of the well-known early work, we discuss representative recent experimental and theoretical work and attempt to interpret the essence of significant modern findings. In the area of local reconnection physics, many significant findings have been made with regard to two- uid physics and are related to the cause of fast reconnection. Profiles of the neutral sheet, Hall currents, and the effects of guide field, collisions, and micro-turbulence are discussed to understand the fundamental processes in a local reconnection layer both in space and laboratory plasmas. While the understanding of the global reconnection dynamics is less developed, notable findings have been made on this issue through detailed documentation of magnetic self-organization phenomena in fusion plasmas. Application of magnetic reconnection physics to astrophysical plasmas is also brie y discussed.

  16. Magnetic Fields in Molecular Cloud Cores

    E-Print Network [OSTI]

    Shantanu Basu

    2004-10-22T23:59:59.000Z

    Observations of magnetic field strengths imply that molecular cloud fragments are individually close to being in a magnetically critical state, even though both magnetic field and column density measurements range over two orders of magnitude. The turbulent pressure also approximately balances the self-gravitational pressure. These results together mean that the one-dimensional velocity dispersion $\\sigv$ is proportional to the mean \\Alf speed of a cloud $\\va$. Global models of MHD turbulence in a molecular cloud show that this correlation is naturally satisfied for a range of different driving strengths of the turbulence. For example, an increase of turbulent driving causes a cloud expansion which also increases $\\va$. Clouds are in a time averaged balance but exhibit large oscillatory motions, particularly in their outer rarefied regions. We also discuss models of gravitational fragmentation in a sheet-like region in which turbulence has already dissipated, including the effects of magnetic fields and ion-neutral friction. Clouds with near-critical mass-to-flux ratios lead to subsonic infall within cores, consistent with some recent observations of motions in starless cores. Conversely, significantly supercritical clouds are expected to produce extended supersonic infall.

  17. Patterned Magnetic Nanostructures and Quantized Magnetic Disks

    E-Print Network [OSTI]

    -increasing demands in data storage and to new applications of magnetic devices in the field of sensors. NewPatterned Magnetic Nanostructures and Quantized Magnetic Disks STEPHEN Y. CHOU Invited Paper, opens up new opportunities for engineering innovative magnetic materials and devices, developing ultra

  18. Landau levels of scalar QED in time-dependent magnetic fields

    SciTech Connect (OSTI)

    Kim, Sang Pyo, E-mail: sangkim@kunsan.ac.kr

    2014-05-15T23:59:59.000Z

    The Landau levels of scalar QED undergo continuous transitions under a homogeneous, time-dependent magnetic field. We analytically formulate the Klein–Gordon equation for a charged spinless scalar as a Cauchy initial value problem in the two-component first order formalism and then put forth a measure that classifies the quantum motions into the adiabatic change, the nonadiabatic change, and the sudden change. We find the exact quantum motion and calculate the pair-production rate when the magnetic field suddenly changes as a step function. -- Highlights: •We study the Landau levels of scalar QED in time-dependent magnetic fields. •Instantaneous Landau levels make continuous transitions but keep parity. •The Klein–Gordon equation is expressed in the two-component first order formalism. •A measure is advanced that characterizes the quantum motions into three categories. •A suddenly changing magnetic field produces pairs of charged scalars from vacuum.

  19. Collective motion in quantum diffusive environment

    E-Print Network [OSTI]

    V. M. Kolomietz; S. Å berg; S. V. Radionov

    2007-06-16T23:59:59.000Z

    The general problem of dissipation in macroscopic large-amplitude collective motion and its relation to energy diffusion of intrinsic degrees of freedom of a nucleus is studied. By applying the cranking approach to the nuclear many-body system, a set of coupled dynamical equations for the collective classical variable and the quantum mechanical occupancies of the intrinsic nuclear states is derived. Different dynamical regimes of the intrinsic nuclear motion and its consequences on time properties of collective dissipation are discussed.

  20. Simulating plant motion with levels of detail

    E-Print Network [OSTI]

    Flannery, Rebecca Lynn

    2013-02-22T23:59:59.000Z

    SIMULATING PLANT MOTION WITH LEVELS OF DETAIL A Senior Honors Thesis by REBECCA LYNN FLANNERY Submitted to the Office of Honors Programs k. Academic Scholarships Texas AkM University in partial fulfillment of the requirements... of the UNIVERSITY UNDERGRADUATE RESEARCH FELLOWS April 2003 Group: Engineering & Physics I SIMULATING PLANT MOTION WITH LEVELS OF DETAIL A Senior Honors Thesis by REBECCA LYNN FLANNERY Submitted to the Office of Honors Programs & Academic Scholarships...

  1. Ground motion: An introduction for accelerator builders

    SciTech Connect (OSTI)

    Fischer, G.E.

    1992-02-01T23:59:59.000Z

    In this seminar we will review some of the characteristics of the major classes of ground motion in order to determine whether their effects must be considered or place fundamental limits on the sitting and/or design of modern storage rings and linear colliders. The classes discussed range in frequency content from tidal deformation and tectonic motions through earthquakes and microseisms. Countermeasures currently available are briefly discussed.

  2. IEEE TRANSACTIONS ON MAGNETICS, VOL. 37, NO. 2, MARCH 2001 949 Track Seek Control for Hard Disk Dual-Stage Servo

    E-Print Network [OSTI]

    Horowitz, Roberto

    was designed in three steps: 1) a voice coil motor (VCM) feedforward controller was designed to prevent-stage actuator, magnetic disk drive, motion control. I. INTRODUCTION THE MOST significant trend in magnetic diskIEEE TRANSACTIONS ON MAGNETICS, VOL. 37, NO. 2, MARCH 2001 949 Track Seek Control for Hard Disk

  3. An optimized magnet for magnetic refrigeration

    E-Print Network [OSTI]

    Bjørk, R; Smith, A; Christensen, D V; Pryds, N

    2014-01-01T23:59:59.000Z

    A magnet designed for use in a magnetic refrigeration device is presented. The magnet is designed by applying two general schemes for improving a magnet design to a concentric Halbach cylinder magnet design and dimensioning and segmenting this design in an optimum way followed by the construction of the actual magnet. The final design generates a peak value of 1.24 T, an average flux density of 0.9 T in a volume of 2 L using only 7.3 L of magnet, and has an average low flux density of 0.08 T also in a 2 L volume. The working point of all the permanent magnet blocks in the design is very close to the maximum energy density. The final design is characterized in terms of a performance parameter, and it is shown that it is one of the best performing magnet designs published for magnetic refrigeration.

  4. On the Kinematics of Undulator Girder Motion

    SciTech Connect (OSTI)

    Welch, J; /SLAC; ,

    2011-08-18T23:59:59.000Z

    The theory of rigid body kinematics is used to derive equations that govern the control and measurement of the position and orientation of undulator girders. The equations form the basis of the girder matlab software on the LCLS control system. The equations are linear for small motion and easily inverted as desired. For reference, some relevant girder geometrical data is also given. Equations 6-8 relate the linear potentiometer readings to the motion of the girder. Equations 9-11 relate the cam shaft angles to the motion of the girder. Both sets are easily inverted to either obtain the girder motion from the angles or readings, or, to find the angles and readings that would give a desired motion. The motion of any point on the girder can be calculated by applying either sets of equations to the two cam-planes and extrapolating in the z coordinate using equation 19. The formulation of the equations is quite general and easily coded via matrix and vector methods. They form the basis of the girder matlab software on the LCLS control system.

  5. Instrumentation for a multichord motional Stark effect diagnostic in KSTAR

    SciTech Connect (OSTI)

    Chung, J., E-mail: jinil@nfri.re.kr; Ko, J. [National Fusion Research Institute, Yuseong, Daejeon 305-333 (Korea, Republic of); De Bock, M. F. M.; Jaspers, R. J. E. [Eindhoven University of Technology, 5612 AZ, Eindhoven (Netherlands)

    2014-11-15T23:59:59.000Z

    The motional Stark effect (MSE) diagnostic is used to measure the radial magnetic pitch angle profile in neutral beam heated plasmas. This information is used to calculate the safety factor, q, with magnetic equilibrium reconstruction codes such as EFIT. The MSE diagnostic is important during active shaping of the q profile to optimize confinement and stability, and it has become a key diagnostic in high performance tokamaks. A multichord photo-elastic modulator (PEM) based MSE system is being developed for a real-time plasma current profile control in Korea Superconducting Tokamak Advanced Research (KSTAR). The PEM-based approach is a standard method that measures the polarization direction of a single Stark line with narrow tunable bandpass filters. A tangential view of the heating beam provides good spatial resolution of 1–3 cm, which provides an opportunity to install 25 spatial channels spanning the major radius from 1.74 m to 2.84 m. Application of real-time control is a long-term technical goal after commissioning the diagnostic in KSTAR, which is expected in 2015. In this paper, we describe the design of this newly-constructed multichord MSE diagnostic in KSTAR.

  6. Classical and Quantum Equations of Motion for a BTZ Black String in AdS Space

    E-Print Network [OSTI]

    Eric Greenwood; Evan Halstead; Peng Hao

    2010-01-24T23:59:59.000Z

    We investigate gravitational collapse of a $(3+1)$-dimensional BTZ black string in AdS space in the context of both classical and quantum mechanics. This is done by first deriving the conserved mass per unit length of the cylindrically symmetric domain wall, which is taken as the classical Hamiltonian of the black string. In the quantum mechanical context, we take primary interest in the behavior of the collapse near the horizon and near the origin (classical singularity) from the point of view of an infalling observer. In the absence of radiation, quantum effects near the horizon do not change the classical conclusions for an infalling observer, meaning that the horizon is not an obstacle for him/her. The most interesting quantum mechanical effect comes in when investigating near the origin. First, quantum effects are able to remove the classical singularity at the origin, since the wave function is non-singular at the origin. Second, the Schr\\"odinger equation describing the behavior near the origin displays non-local effects, which depend on the energy density of the domain wall. This is manifest in that derivatives of the wavefunction at one point are related to the value of the wavefunction at some other distant point.

  7. Crustal motion in Indonesia from Global Positioning System measurements

    E-Print Network [OSTI]

    McCaffrey, Robert

    Crustal motion in Indonesia from Global Positioning System measurements Y. Bock,1 L. Prawirodirdjo: crustal motion, Indonesia tectonics, GPS, current plate motions, Southeast Asia Citation: Bock, Y., L, Crustal motion in Indonesia from Global Positioning System measurements, J. Geophys. Res., 108(B8), 2367

  8. Superconducting Magnet Division

    E-Print Network [OSTI]

    Gupta, Ramesh

    Superconducting Magnet Division Permanent Magnet Designs with Large Variations in Field Strength the residual field of the magnetized bricks by concentrating flux lines at the iron pole. Low Field Design Medium Field Design Superconducting Magnet Division Dipole and Quadrupole Magnets for RHIC e

  9. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01T23:59:59.000Z

    A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

  10. Can We Distinguish Biological Motions of Virtual Humans? Perceptual Study With Captured Motions of Weight Lifting.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Information Systems-- Animations ­ Artificial, augmented, and virtual realities Keywords: Human Motions of Weight Lifting. Ludovic Hoyet IRISA - INRIA Bunraku Team, Rennes Franck Multon Mouvement Sport Sant of Edinburgh Figure 1: Subject lifting a 6kg dumbbell: video of a real motion (up) and corresponding captured

  11. 6.641 Electromagnetic Fields, Forces, and Motion, Spring 2003

    E-Print Network [OSTI]

    Zahn, Markus, 1946-

    Electric and magnetic quasistatic forms of Maxwell's equations applied to dielectric, conduction, and magnetization boundary value problems. Electromagnetic forces, force densities, and stress tensors, including magnetization ...

  12. Nanostructured magnetic materials

    E-Print Network [OSTI]

    Chan, Keith T.

    2011-01-01T23:59:59.000Z

    Magnetism and Magnetic Materials Conference, Atlanta, GA (Nanostructured Magnetic Materials by Keith T. Chan Doctor ofinduced by a Si-based material occurs at a Si/Ni interface

  13. Fuel-motion diagnostics and cineradiography

    SciTech Connect (OSTI)

    DeVolpi, A.

    1982-09-01T23:59:59.000Z

    Nuclear and non-nuclear applications of cineradiography are reviewed, with emphasis on diagnostic instrumentation for in-pile transient-reactor safety testing of nuclear fuel motion. The primary instrument for this purpose has been the fast-neutron hodoscope, which has achieved quantitative monitoring of time, location, mass, and velocity of fuel movement under the difficult conditions associated with transient-reactor experiments. Alternative diagnostic devices that have been developed have not matched the capabilities of the hodoscope. Other applications for the fuel-motion diagnostic apparatus are also evolving, including time-integrated radiography and direct time- and space-resolved fuel-pin power monitoring. Although only two reactors are now actively equipped with high-resolution fuel-motion diagnostic systems, studies and tests have been carried out in and for many other reactors.

  14. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect (OSTI)

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1989-03-01T23:59:59.000Z

    Twenty-three laced permanent magnet quadrupole drift tube magnets have been constructed, tested, and installed in the SuperHILAC heavy ion linear accelerator at LBL, marking the first accelerator use of this new type of quadrupole. The magnets consist of conventional tape-wound quadrupole electromagnets, using iron pole-pieces, with permanent magnet material (samarium cobalt) inserted between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the individual quadrupole magnets in a drift tube linac is never reversed, we can take advantage of this asymmetrical saturation to provide about 20% greater focusing strength than is available with conventional quadrupoles, while replacing the vanadium permendur poletips with iron poletips. Comparisons between these magnets and conventional tape-wound quadrupoles will be presented. 3 refs., 5 figs.

  15. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    Superconducting 30-MJ Energy Storage Coil", Proc. 19 80 ASC,Superconducting Magnetic Energy Storage Plant", IEEE Trans.SlIperconducting Magnetic Energy Storage Unit", in Advances

  16. SUPERCONDUCTING MAGNETIC ENERGY STORAGE

    E-Print Network [OSTI]

    Hassenzahl, W.

    2011-01-01T23:59:59.000Z

    Design of the BPA Superconducting 30-MJ Energy Storagefor a Utility Scale Superconducting Magnetic Energy Storagefor a Lnrge Scale Superconducting Magnetic Energy Storage

  17. An analysis of guard cell motion

    E-Print Network [OSTI]

    Wu, Hsin-i

    1977-01-01T23:59:59.000Z

    AN ANALYSIS OF GUARD CELL MOTION A Thesis by BSIN-I WU Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December, 1977 Ma]or Sub]ect: Industrial... Engineering AN ANALYSIS OF GUARD CELL MOTION A Thesis by HSIN-I WU Approved as to style and content by: L. Curry (I. En. ) Newton C. Ellis (I. En. ) c' eter J. H. Sharpe (B. E. ) Dar d J. Ha tfiel (Math) December 1977 I &'(2(i& R) ABSTRACT...

  18. Telescoping magnetic ball bar test gage

    DOE Patents [OSTI]

    Bryan, J.B.

    1982-03-15T23:59:59.000Z

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengagable servo drives which cannot be clutched out. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine.

  19. The feasibility of head motion tracking in helical CT: A step toward motion correction

    SciTech Connect (OSTI)

    Kim, Jung-Ha [Medical Radiation Sciences, University of Sydney, NSW 2141 (Australia); Nuyts, Johan [Department of Nuclear Medicine, Katholieke Universiteit, Leuven, Belgium and Medical Imaging Research Center, Katholieke Universiteit, Leuven (Belgium); Kuncic, Zdenka [School of Physics, University of Sydney, NSW 2006 (Australia); Fulton, Roger [Medical Radiation Sciences, University of Sydney, NSW 2141 (Australia); School of Physics, University of Sydney, NSW 2006 (Australia); Department of Medical Physics, Westmead Hospital, Westmead, NSW 2145 (Australia)

    2013-04-15T23:59:59.000Z

    Purpose: To establish a practical and accurate motion tracking method for the development of rigid motion correction methods in helical x-ray computed tomography (CT). Methods: A commercially available optical motion tracking system provided 6 degrees of freedom pose measurements at 60 Hz. A 4 Multiplication-Sign 4 calibration matrix was determined to convert raw pose data acquired in tracker coordinates to a fixed CT coordinate system with origin at the isocenter of the scanner. Two calibration methods, absolute orientation (AO), and a new method based on image registration (IR), were compared by means of landmark analysis and correlation coefficient in phantom images coregistered using the derived motion transformations. Results: Transformations calculated using the IR-derived calibration matrix were found to be more accurate, with positional errors less than 0.5 mm (mean RMS), and highly correlated image voxel intensities. The AO-derived calibration matrix yielded larger mean RMS positional errors ( Asymptotically-Equal-To 1.0 mm), and poorer correlation coefficients. Conclusions: The authors have demonstrated the feasibility of accurate motion tracking for retrospective motion correction in helical CT. Their new IR-based calibration method based on image registration and function minimization was simpler to perform and delivered more accurate calibration matrices. This technique is a useful tool for future work on rigid motion correction in helical CT and potentially also other imaging modalities.

  20. Motion Perception Model and Its Application

    E-Print Network [OSTI]

    Oliva, Aude

    of the blind, and brain-computer interface system etc. Furthermore, brain-like motion detection algorithms also a meaningful challenge to be solved. This thesis first introduces the psychophysical experiments on human applica- tions. Main contributions of this thesis are listed as follows. #12; First of all, we collect

  1. Strong-Motion Instrumentation Programs in Taiwan

    E-Print Network [OSTI]

    Wu, Yih-Min

    western Taiwan, with high- rise buildings as a consequence of developing economy, is vulnerable-Motion Accelerograph Array in Taiwan, Phase 1 (SMART-1 Array) SMART-1 Array was set up in Lotung in 1980 and closed and University of California, Berkeley. The SMART-1 Array consisted of a central site and accelerographs in three

  2. Ship Motion Prediction for Maritime Flight Operations

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    prediction model, resulting from complicated wave-excitation dynamics caused by the local stochastic sea and stochastic sea state disturbances. An appropriate model aiming to feature the characteristics of the dynamic estimation model in the presence of uncertain stochastic processes (e.g. wind, sea wave), unknown ship motion

  3. N000149510521 Estimating Relative Vehicle Motions

    E-Print Network [OSTI]

    Markovitch, Shaul

    CAR­TR­881 CS­TR­3882 N00014­95­1­0521 March 1998 Estimating Relative Vehicle Motions in Traffic for Automation Research University of Maryland College Park, MD 20742­3275 2 Computer Science Department George of Technology Haifa, Israel 32000 Abstract Autonomous operation of a vehicle on a road calls for understanding

  4. Clearance Based Path Optimization for Motion Planning

    E-Print Network [OSTI]

    Utrecht, Universiteit

    Abstract Many motion planning techniques, like the probabilistic roadmap method (PRM), gen- erate low] and humanoid robot planning [13]. A commonly used technique for planning paths is the Probabilistic Roadmap. 1.1 Probabilistic Roadmap Method The probabilistic roadmap method consists of two phases

  5. Clearance Based Path Optimization for Motion Planning

    E-Print Network [OSTI]

    Utrecht, Universiteit

    Abstract Many motion planning techniques, like the probabilistic roadmap method (PRM), gen­ erate low] and humanoid robot planning [13]. A commonly used technique for planning paths is the Probabilistic Roadmap.1 Probabilistic Roadmap Method The probabilistic roadmap method consists of two phases: a construction and a query

  6. On the Topic of Motion Integrals

    E-Print Network [OSTI]

    Bertinato, Christopher

    2013-04-02T23:59:59.000Z

    An integral of motion is a function of the states of a dynamical system that is constant along the system’s trajectories. Integrals are known for their utility as a means of reducing the dimension of a system, effectively leaving only one...

  7. Chemistry in Motion: Tiny Synthetic Motors

    E-Print Network [OSTI]

    Peter H. Colberg; Shang Yik Reigh; Bryan Robertson; Raymond Kapral

    2014-11-03T23:59:59.000Z

    In this Account, we describe how synthetic motors that operate by self-diffusiophoresis make use of a self-generated concentration gradient to drive motor motion. A description of propulsion by self-diffusiophoresis is presented for Janus particle motors comprising catalytic and noncatalytic faces. The properties of the dynamics of chemically powered motors are illustrated by presenting the results of particle-based simulations of sphere-dimer motors constructed from linked catalytic and noncatalytic spheres. The geometries of both Janus and sphere-dimer motors with asymmetric catalytic activity support the formation of concentration gradients around the motors. Because directed motion can occur only when the system is not in equilibrium, the nature of the environment and the role it plays in motor dynamics are described. Rotational Brownian motion also acts to limit directed motion, and it has especially strong effects for very small motors. We address the following question: how small can motors be and still exhibit effects due to propulsion, even if only to enhance diffusion? Synthetic motors have the potential to transform the manner in which chemical dynamical processes are carried out for a wide range of applications.

  8. Motion Control of Robot Manipulators with MATLAB

    E-Print Network [OSTI]

    Siena, Università di

    Motion Control of Robot Manipulators with MATLAB · By Francesco Chinello, Stefano Scheggi, Fabio Morbidi, and Domenico Prattichizzo 1070-9932/11/$26.00ª2011 IEEE DECEMBER 2011 · IEEE ROBOTICS robot manipulators. The KUKA Control Toolbox (KCT) is a collection of MATLAB functions developed

  9. Electromagnetic Radiation and Motion of Really Shaped Particle

    E-Print Network [OSTI]

    Jozef Klacka

    2001-08-13T23:59:59.000Z

    Relativistically covariant form of equation of motion for real particle (neutral in charge) under the action of electromagnetic radiation is derived. Various formulations of the equation of motion in the proper frame of reference of the particle are used. Main attention is devoted to the reformulation of the equation of motion in the general frame of reference, e. g., in the frame of reference of the source of electromagnetic radiation. This is the crucial form of equation of motion in applying it to motion of particles (cosmic dust, asteroids, ...) in the Universe if electromagnetic radiation acts on the particles. General relativistic equation of motion is presented.

  10. Laced permanent magnet quadrupole drift tube magnets

    SciTech Connect (OSTI)

    Feinberg, B.; Behrsing, G.U.; Halbach, K.; Marks, J.S.; Morrison, M.E.; Nelson, D.H.

    1988-10-01T23:59:59.000Z

    A laced permanent magnet quadrupole drift tube magnet has been constructed for a proof-of-principle test. The magnet is a conventional tape-wound quadrupole electromagnet, using iron pole- pieces, with the addition of permanent magnet material (neodymium iron) between the poles to reduce the effects of saturation. The iron is preloaded with magnetic flux generated by the permanent magnet material, resulting in an asymmetrical saturation curve. Since the polarity of the quadrupole magnets in a drift tube linac is not reversed we can take advantage of this asymmetrical saturation to provide greater focusing strength. The magnet configuration has been optimized and the vanadium permendur poles needed in a conventional quadrupole have been replaced with iron poles. The use of permanent magnet material has allowed us to increase the focusing strength of the magnet by about 20% over that of a conventional tape-wound quadrupole. Comparisons will be made between this magnet and the conventional tape-wound quadrupole. 3 refs., 5 figs.

  11. ELECTRON MICROSCOPY STUDY OF THE FERROELECTRIC DOMAINS AND DOMAIN WALL STRUCTURE IN Pb.52Ti.48O3

    E-Print Network [OSTI]

    Goo, E.K.W.

    2010-01-01T23:59:59.000Z

    Energy under Contract No. W-7405-ENG-48. a) Present address:of Energy under Contract W-7405-ENG-48 ELECTRON MICROSCOPYunder Contract No. W-7405-ENG-48. I. INTRODUCTION Lead

  12. Quantum Dynamics of Spin Wave Propagation through Domain Walls S. YUAN, H. DE RAEDT and S. MIYASHITA1;2

    E-Print Network [OSTI]

    as a concept for a new generation of nonvolatile memory storage and logical devices.8) On the other hand nanostructures which is treated as a kind of soliton in a continuous medium. Such structure can be created of storing information or even performing logic functions, and to offer new types of electronics devices1

  13. Domain wall freezing in KDP-type ferroelectrics V.H. Schmidt*, G. Bohannan, D. Arbogast, G. Tuthill

    E-Print Network [OSTI]

    for individual protons in O­H···O hydrogen bonds to shift position and permit the wall to move. In this paper we investigating the prospect of a phase transition below the ferroelectric transi- tion. A hydrogen gas cryostat. Hysteresis loops showed nearly constant satura- tion polarization Ps and coercive field Ec from 120 K down

  14. Introduction Magnetic Anisotropy of

    E-Print Network [OSTI]

    Rossak, Wilhelm R.

    not completely understood interesting for dilute magnetic semiconductors (DMSs) transparent ferromagnets

  15. Magnetic Imaging Wolfgang Kuch

    E-Print Network [OSTI]

    Kuch, Wolfgang

    Magnetic Imaging Wolfgang Kuch Freie Universit¨at Berlin, Institut f¨ur Experimentalphysik, Arnimallee 14, 14195 Berlin, Germany kuch@physik.fu-berlin.de Abstract. Imaging of magnetic domains has- ern techniques is used nowadays routinely for magnetic imaging of magnetic ma- terials

  16. Superconducting Magnet Division

    E-Print Network [OSTI]

    McDonald, Kirk

    Superconducting Magnet Division Ramesh Gupta 20T Target Solenoid with HTS Insert Solenoid Capture Laboratory New York, USA http://www.bnl.gov/magnets/staff/gupta #12;Superconducting Magnet Division Ramesh of HTS may significantly reduce the amount of Tungsten shielding · Summary #12;Superconducting Magnet

  17. Motion and equilibrium of a spheromak in a toroidal flux conserver M. R. Brown,a) D. M. Cutrer, and P. M. Beilan

    E-Print Network [OSTI]

    Brown, Michael R.

    Motion and equilibrium of a spheromak in a toroidal flux conserver M. R. Brown,a) D. M. Cutrer field). First, a fit of the in situ magnetic data of the spheromak in the tokamak vesselto a simple of the spheromakin the dc toroidal field of the tokamak are relevant to theories of spheromak/tokamak interaction.3

  18. PHYS 626 --Fundamentals of Plasma Physics --Section 6.4-6.5 1. Using the ideal MHD equation of motion, an energy equation can be derived. It is

    E-Print Network [OSTI]

    Ng, Chung-Sang

    of motion, an energy equation can be derived. It is simply the continuity equation of energy density, which is the sum of kinetic energy density mU2 /2, magnetic energy density B2 /2µ0, and the internal energy density p/( -1). The total energy obtained by integrating the energy density over the whole space

  19. Hydrostatic Level Sensors as High Precision Ground Motion Instrumentation for Tevatron and Other Energy Frontier Accelerators

    SciTech Connect (OSTI)

    Volk, James; Hansen, Sten; Johnson, Todd; Jostlein, Hans; Kiper, Terry; Shiltsev, Vladimir; Chupyra, Andrei; Kondaurov, Mikhail; Medvedko, Anatoly; Parkhomchuk, Vasily; Singatulin, Shavkat

    2012-01-01T23:59:59.000Z

    Particle accelerators require very tight tolerances on the alignment and stability of their elements: magnets, accelerating cavities, vacuum chambers, etc. In this article we describe the Hydrostatic Level Sensors (HLS) for very low frequency measurements used in a variety of facilities at Fermilab. We present design features of the sensors, outline their technical parameters, describe their test and calibration procedures, discuss different regimes of operation and give few illustrative examples of the experimental data. Detail experimental results of the ground motion measurements with these detectors will be presented in subsequent papers.

  20. A high spatial resolution Stokes polarimeter for motional Stark effect imaging

    SciTech Connect (OSTI)

    Thorman, Alex; Michael, Clive; Howard, John [Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2013-06-15T23:59:59.000Z

    We describe an enhanced temporally switched interfero-polarimeter that has been successfully deployed for high spatial resolution motional Stark effect imaging on the KSTAR superconducting tokamak. The system utilizes dual switching ferroelectric liquid crystal waveplates to image the full Stokes vector of elliptically polarized and Doppler-shifted Stark-Zeeman Balmer-alpha emission from high energy neutral beams injected into the magnetized plasma. We describe the optical system and compare its performance against a Mueller matrix model that takes account of non-ideal performance of the switching ferro-electric liquid crystal waveplates and other polarizing components.

  1. Apparatus and method for reducing inductive coupling between levitation and drive coils within a magnetic propulsion system

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2001-01-01T23:59:59.000Z

    An apparatus and method is disclosed for reducing inductive coupling between levitation and drive coils within a magnetic levitation system. A pole array has a magnetic field. A levitation coil is positioned so that in response to motion of the magnetic field of the pole array a current is induced in the levitation coil. A first drive coil having a magnetic field coupled to drive the pole array also has a magnetic flux which induces a parasitic current in the levitation coil. A second drive coil having a magnetic field is positioned to attenuate the parasitic current in the levitation coil by canceling the magnetic flux of the first drive coil which induces the parasitic current. Steps in the method include generating a magnetic field with a pole array for levitating an object; inducing current in a levitation coil in response to motion of the magnetic field of the pole array; generating a magnetic field with a first drive coil for propelling the object; and generating a magnetic field with a second drive coil for attenuating effects of the magnetic field of the first drive coil on the current in the levitation coil.

  2. Frequency analysis and sheared reconstruction for rendering motion blur

    E-Print Network [OSTI]

    Egan, Kevin

    Motion blur is crucial for high-quality rendering, but is also very expensive. Our first contribution is a frequency analysis of motion-blurred scenes, including moving objects, specular reflections, and shadows. We show ...

  3. Motion-to-Energy (M2Eâ?¢) Power Generation Technology

    ScienceCinema (OSTI)

    Idaho National Laboratory

    2010-01-08T23:59:59.000Z

    INL researchers developed M2E, a new technology that converts motion to energy. M2E uses an innovative, optimized microgenerator with power management circuitry that kinetically charges mobile batteries from natural motion such as walking. To learn more,

  4. Motion-to-Energy (M2E) Power Generation Technology

    ScienceCinema (OSTI)

    INL

    2009-09-01T23:59:59.000Z

    INL researchers developed M2E, a new technology that converts motion to energy. M2E uses an innovative, optimized microgenerator with power management circuitry that kinetically charges mobile batteries from natural motion such as walking.

  5. Production-Intent Lost-Motion Variable Valve Actuation Systems...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Production-Intent Lost-Motion Variable Valve Actuation Systems Production-Intent Lost-Motion Variable Valve Actuation Systems Variable valve actuation with onoff IEGR pre-bump is...

  6. Intuitive Generation of Realistic Motions for Articulated Human Characters

    E-Print Network [OSTI]

    Min, Jianyuan

    2013-01-15T23:59:59.000Z

    create and control life-like human motions. This dissertation focuses on exploring theory, algorithms and applications that enable novice users to quickly and easily create and control natural-looking motions, including both full-body movement and hand...

  7. Motion-to-Energy (M2E) Power Generation Technology

    SciTech Connect (OSTI)

    INL

    2008-05-30T23:59:59.000Z

    INL researchers developed M2E, a new technology that converts motion to energy. M2E uses an innovative, optimized microgenerator with power management circuitry that kinetically charges mobile batteries from natural motion such as walking.

  8. Motion-to-Energy (M2Eâ„¢) Power Generation Technology

    SciTech Connect (OSTI)

    Idaho National Laboratory

    2008-05-30T23:59:59.000Z

    INL researchers developed M2E, a new technology that converts motion to energy. M2E uses an innovative, optimized microgenerator with power management circuitry that kinetically charges mobile batteries from natural motion such as walking. To learn more,

  9. Perception and processing of self-motion cues 

    E-Print Network [OSTI]

    Smith, Michael Thomas

    2013-11-28T23:59:59.000Z

    The capacity of animals to navigate through familiar or novel environments depends crucially on the integration of a disparate set of self motion cues. The study begins with one of the most simple, planar visual motion, ...

  10. Robust hybrid control for autonomous vehicle motion planning

    E-Print Network [OSTI]

    Frazzoli, Emilio, 1970-

    2001-01-01T23:59:59.000Z

    This dissertation focuses on the problem of motion planning for agile autonomous vehicles. In realistic situations, the motion planning problem must be solved in real-time, in a dynamic and uncertain environment. The ...

  11. absolute proper motions: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    H. Lenhardt; H. Schwan 2000-07-21 25 Lick Northern Proper Motion Program. III. Lick NPM2 Catalog Astrophysics (arXiv) Summary: The Lick Northern Proper Motion (NPM) program, a...

  12. apparent proper motion: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    with a... Hirshkowitz, Amy 2014-08-05 46 Lick Northern Proper Motion Program. III. Lick NPM2 Catalog Astrophysics (arXiv) Summary: The Lick Northern Proper Motion (NPM) program, a...

  13. Optimal Motion Planning with constraints for mobile robot navigation

    E-Print Network [OSTI]

    Pearce, Roger Allan

    2013-02-22T23:59:59.000Z

    -dimensional space. Motion Planning, or path planning for robots, becomes increasing difficult as the dimension of the planning space increases with the robot's degrees of freedom (dof). While the running time of deterministic motion planning algorithms grows...

  14. Exploiting quaternions to support expressive interactive character motion

    E-Print Network [OSTI]

    Johnson, Michael Patrick, 1971-

    2003-01-01T23:59:59.000Z

    A real-time motion engine for interactive synthetic characters, either virtual or physical, needs to allow expressivity and interactivity of motion in order to maintain the illusion of life. Canned animation examples from ...

  15. Active dipole clusters: from helical motion to fission

    E-Print Network [OSTI]

    Andreas Kaiser; Katarina Popowa; Hartmut Löwen

    2015-05-29T23:59:59.000Z

    The structure of a finite particle cluster is typically determined by total energy minimization. Here we consider the case where a cluster of soft sphere dipoles becomes active, i.e. when the individual particles exhibit an additional self-propulsion along their dipole moments. We numerically solve the overdamped equations of motion for soft-sphere dipoles in a solvent. Starting from an initial metastable dipolar cluster, the self-propulsion generates a complex cluster dynamics. The final cluster state has in general a structure widely different to the initial one, the details depend on the model parameters and on the protocol of how the self-propulsion is turned on. The center-of-mass of the cluster moves on a helical path, the details of which are governed by the initial cluster magnetization. An instantaneous switch to a high self-propulsion leads to fission of the cluster. However, fission does not occur if the self-propulsion is increased slowly to high strengths. Our predictions can be verified through experiments with self-phoretic colloidal Janus-particles and for macroscopic self-propelled dipoles in a highly viscous solvent.

  16. Why is high-Tc superconductivity exciting?

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    magnetic field at T 1 K measured by muon spin rotation Niedermayer, Budnick, et al. PRL 80, 3843 (1998) Hole segregation to antiphase domain walls 1D model 2D extrapolation...

  17. Learning Probabilistic Models for Visual Motion David Alexander Ross

    E-Print Network [OSTI]

    Roweis, Sam

    Mellon University Motion Capture Database http://mocap.cs.cmu.edu/ (created with funding from NSF EIA

  18. Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets

    SciTech Connect (OSTI)

    None

    2010-10-01T23:59:59.000Z

    Broad Funding Opportunity Announcement Project: GE is using nanomaterials technology to develop advanced magnets that contain fewer rare earth materials than their predecessors. Nanomaterials technology involves manipulating matter at the atomic or molecular scale, which can represent a stumbling block for magnets because it is difficult to create a finely grained magnet at that scale. GE is developing bulk magnets with finely tuned structures using iron-based mixtures that contain 80% less rare earth materials than traditional magnets, which will reduce their overall cost. These magnets will enable further commercialization of HEVs, EVs, and wind turbine generators while enhancing U.S. competitiveness in industries that heavily utilize these alternatives to rare earth minerals.

  19. Motions and world-line deviations in Einstein-Maxwell theory

    E-Print Network [OSTI]

    A. Balakin; J. W. van Holten; R. Kerner

    2000-09-06T23:59:59.000Z

    We examine the motion of charged particles in gravitational and electro-magnetic background fields. We study in particular the deviation of world lines, describing the relative acceleration between particles on different space-time trajectories. Two special cases of background fields are considered in detail: (a) pp-waves, a combination of gravitational and electro-magnetic polarized plane waves travelling in the same direction; (b) the Reissner-Nordstr{\\o}m solution. We perform a non-trivial check by computing the precession of the periastron for a charged particle in the Reissner-Nordstr{\\o}m geometry both directly by solving the geodesic equation, and using the world-line deviation equation. The results agree to the order of approximation considered.

  20. ForPeerReview SMC Framework in Motion Control Systems

    E-Print Network [OSTI]

    Yanikoglu, Berrin

    , Interconnected Systems. 1. INTRODUCTION Modern motion control systems are more and more acting as "agentsForPeerReview SMC Framework in Motion Control Systems Journal: International Journal of Adaptive, Mechatronics Keywords: Motion Control, Sliding Mode Control, Bilateral Control , Interconnected Systems http

  1. Electromagnetic radiation and motion of arbitrarily shaped particle

    E-Print Network [OSTI]

    Jozef Klacka

    2001-07-06T23:59:59.000Z

    Covariant form of equation of motion for arbitrarily shaped particle in the electromagnetic radiation field is presented. Equation of motion in the proper frame of the particle uses the radiation pressure cross section 3 $\\times$ 3 matrix. The obtained equation of motion is compared with known result.

  2. Computational Modeling of Brain Dynamics during Repetitive Head Motions

    E-Print Network [OSTI]

    Burtscher, Martin

    Computational Modeling of Brain Dynamics during Repetitive Head Motions Igor Szczyrba School the HIC scale to arbitrary head motions. Our simulations of the brain dynamics in sagittal and horizontal injury modeling, resonance effects 1 Introduction A rapid head motion can result in a severe brain injury

  3. Motion Prediction for Moving Objects: a Statistical Approach

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Motion Prediction for Moving Objects: a Statistical Approach Dizan Vasquez & Thierry Fraichard with those objects requires the ability to predict their future motion (e.g. for predator evasion, prey hunting, collision avoidance, etc.). Motion prediction is a research area with applications in many

  4. Bounded, Periodic Relative Motion using Canonical Epicyclic Orbital Elements

    E-Print Network [OSTI]

    Rowley, Clarence W.

    Bounded, Periodic Relative Motion using Canonical Epicyclic Orbital Elements N. Jeremy Kasdin using canonical perturbation theory for studying relative motion trajectories and for finding simple motion [2, 3, 4, 5]. This has the advantage that Lagrange's planetary equations (LPEs) or Gauss

  5. Atlas: A Novel Kinematic Architecture for Six DOF Motion Platforms

    E-Print Network [OSTI]

    Hayes, John

    Atlas: A Novel Kinematic Architecture for Six DOF Motion Platforms M.J.D. HAYES, R.G. LANGLOIS alternative motion platform configurations and developed a novel concept that overcomes existing limitations. This paper presents an overview of the Atlas platform: a novel six DOF motion platform architecture

  6. Ground motion data for International Collider models

    SciTech Connect (OSTI)

    Volk, J.T.; LeBrun, P.; Shiltsev, V.; Singatulin, S.; /Fermilab

    2007-11-01T23:59:59.000Z

    The proposed location for the International Linear Collider (ILC) in the Americas region is Fermilab in Batavia Illinois. If built at this location the tunnels would be located in the Galena Platteville shale at a depth of 100 or more meters below the surface. Studies using hydro static water levels and seismometers have been conducted in the MINOS hall and the LaFrange Mine in North Aurora Illinois to determine the level of ground motion. Both these locations are in the Galena Platteville shale and indicate the typical ground motion to be expected for the ILC. The data contains both natural and cultural noise. Coefficients for the ALT law are determined. Seismic measurements at the surface and 100 meters below the surface are presented.

  7. Controlling inertial focussing using rotational motion

    E-Print Network [OSTI]

    Prohm, Christopher; Stark, Holger

    2014-01-01T23:59:59.000Z

    In inertial microfluidics lift forces cause a particle to migrate across streamlines to specific positions in the cross section of a microchannel. We control the rotational motion of a particle and demonstrate that this allows to manipulate the lift-force profile and thereby the particle's equilibrium positions. We perform two-dimensional simulation studies using the method of multi-particle collision dynamics. Particles with unconstrained rotational motion occupy stable equilibrium positions in both halfs of the channel while the center is unstable. When an external torque is applied to the particle, two equilibrium positions annihilate by passing a saddle-node bifurcation and only one stable fixpoint remains so that all particles move to one side of the channel. In contrast, non-rotating particles accumulate in the center and are pushed into one half of the channel when the angular velocity is fixed to a non-zero value.

  8. Intelligent Motion Planning and Analysis with Probabilistic Roadmap Methods for the Study of Complex and High-Dimensional Motions

    E-Print Network [OSTI]

    Tapia, Lydia

    2011-02-22T23:59:59.000Z

    robots and proteins is highly dependent on their motions. In order to study motions in these two divergent domains, the same underlying algorithmic framework can be applied. This method is derived from probabilistic roadmap methods (PRMs) originally...

  9. Collective Motion of Vibrated Polar Disks

    E-Print Network [OSTI]

    Julien Deseigne; Olivier Dauchot; Hugues Chatè

    2010-04-09T23:59:59.000Z

    We experimentally study a monolayer of vibrated disks with a built-in polar asymmetry which enables them to move quasi-balistically on a large persistence length. Alignment occurs during collisions as a result of self-propulsion and hard core repulsion. Varying the amplitude of the vibration, we observe the onset of large-scale collective motion and the existence of giant number fluctuations with a scaling exponent in agreement with the predicted theoretical value.

  10. Compression of ground-motion data

    SciTech Connect (OSTI)

    Long, J.W.

    1981-04-01T23:59:59.000Z

    Ground motion data has been recorded for many years at Nevada Test Site and is now stored on thousands of digital tapes. The recording format is very inefficient in terms of space on tape. This report outlines a method to compress the data onto a few hundred tapes while maintaining the accuracy of the recording and allowing restoration of any file to the original format for future use. For future digitizing a more efficient format is described and suggested.

  11. Magnetic infrasound sensor

    DOE Patents [OSTI]

    Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)

    2006-11-14T23:59:59.000Z

    A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.

  12. Management of Respiratory Motion in Extracorporeal High-Intensity Focused Ultrasound Treatment in Upper Abdominal Organs: Current Status and Perspectives

    SciTech Connect (OSTI)

    Muller, A., E-mail: arnaud.muller@chu-lyon.fr [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France); Petrusca, L.; Auboiroux, V. [University of Geneva, Department of Radiology, Faculty of Medicine (Switzerland)] [University of Geneva, Department of Radiology, Faculty of Medicine (Switzerland); Valette, P. J. [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France)] [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France); Salomir, R. [University of Geneva, Department of Radiology, Faculty of Medicine (Switzerland)] [University of Geneva, Department of Radiology, Faculty of Medicine (Switzerland); Cotton, F. [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France)] [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France)

    2013-12-15T23:59:59.000Z

    Extracorporeal high-intensity focused ultrasound (HIFU) is a minimally invasive therapy considered with increased interest for the ablation of small tumors in deeply located organs while sparing surrounding critical tissues. A multitude of preclinical and clinical studies have showed the feasibility of the method; however, concurrently they showed several obstacles, among which the management of respiratory motion of abdominal organs is at the forefront. The aim of this review is to describe the different methods that have been proposed for managing respiratory motion and to identify their advantages and weaknesses. First, we specify the characteristics of respiratory motion for the liver, kidneys, and pancreas and the problems it causes during HIFU planning, treatment, and monitoring. Second, we make an inventory of the preclinical and clinical approaches used to overcome the problem of organ motion. Third, we analyze their respective benefits and drawbacks to identify the remaining physical, technological, and clinical challenges. We thereby consider the outlook of motion compensation techniques and those that would be the most suitable for clinical use, particularly under magnetic resonance thermometry monitoring.

  13. ON HYDRODYNAMIC MOTIONS IN DEAD ZONES

    SciTech Connect (OSTI)

    Oishi, Jeffrey S. [Department of Astronomy, 601 Campbell Hall, University of California at Berkeley, Berkeley, CA 94720-3411 (United States); Mac Low, Mordecai-Mark, E-mail: jsoishi@astro.berkeley.ed, E-mail: mordecai@amnh.or [Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024-5192 (United States)

    2009-10-20T23:59:59.000Z

    We investigate fluid motions near the midplane of vertically stratified accretion disks with highly resistive midplanes. In such disks, the magnetorotational instability drives turbulence in thin layers surrounding a resistive, stable dead zone. The turbulent layers in turn drive motions in the dead zone. We examine the properties of these motions using three-dimensional, stratified, local, shearing-box, non-ideal, magnetohydrodynamical simulations. Although the turbulence in the active zones provides a source of vorticity to the midplane, no evidence for coherent vortices is found in our simulations. It appears that this is because of strong vertical oscillations in the dead zone. By analyzing time series of azimuthally averaged flow quantities, we identify an axisymmetric wave mode particular to models with dead zones. This mode is reduced in amplitude, but not suppressed entirely, by changing the equation of state from isothermal to ideal. These waves are too low frequency to affect sedimentation of dust to the midplane, but may have significance for the gravitational stability of the resulting midplane dust layers.

  14. Magnetic Fields of Uranus and Neptune: Metallic Fluid Hydrogen

    E-Print Network [OSTI]

    Nellis, W J

    2015-01-01T23:59:59.000Z

    The magnetic fields of the Ice Giant Planets Uranus and Neptune (U/N) are unique in the solar system. Based on a substantial database measured on Earth for representative planetary fluids at representative dynamic pressures up to 200 GPa (2 Mbar) and a few 1000 K, the complex magnetic fields of U/N are (i) probably made primarily by degenerate metallic fluid H (MFH) at or near the crossover from the H-He envelopes to Ice cores at ~100 GPa (Mbar) pressures and normalized radii of ~90% of the radii of U/N; (ii) because those magnetic fields are made relatively close to the surfaces of U/N, non-dipolar fields can be expected; (iii) the Ice cores are most probably a heterogeneous fluid mixture of H, N, O, C, Fe/Ni and silicate-oxides and their mutual reaction products at high pressures and temperatures; (iv) the shapes of the magnetic fields are probably caused by weak coupling between rotational motions of U/N and convective motions of conducting fluids in dynamos that make those magnetic fields. Ironically, the...

  15. Tamper resistant magnetic stripes

    DOE Patents [OSTI]

    Naylor, Richard Brian (Albuquerque, NM); Sharp, Donald J. (Albuquerque, NM)

    1999-01-01T23:59:59.000Z

    This invention relates to a magnetic stripe comprising a medium in which magnetized particles are suspended and in which the encoded information is recorded by actual physical rotation or alignment of the previously magnetized particles within the flux reversals of the stripe which are 180.degree. opposed in their magnetic polarity. The magnetized particles are suspended in a medium which is solid, or physically rigid, at ambient temperatures but which at moderately elevated temperatures, such as 40.degree. C., is thinable to a viscosity permissive of rotation of the particles therein under applications of moderate external magnetic field strengths within acceptable time limits.

  16. Electro-Mechanical Resonant Magnetic Field Sensor

    E-Print Network [OSTI]

    Temnykh, A B; Temnykh, Alexander B.; Lovelace, Richard V. E.

    2002-01-01T23:59:59.000Z

    We describe a new type of magnetic field sensor which is termed an Electro-Mechanical Resonant Sensor (EMRS). The key part of this sensor is a small conductive elastic element with low damping rate and therefore a high Q fundamental mode of frequency $f_1$. An AC current is driven through the elastic element which, in the presence of a magnetic field, causes an AC force on the element. When the frequency of the AC current matches the resonant frequency of the element, maximum vibration of the element occurs and this can be measured precisely by optical means. We have built and tested a model sensor of this type using for the elastic element a length of copper wire of diameter 0.030 mm formed into a loop shape. The wire motion was measured using a light emitting diode photo-transistor assembly. This sensor demonstrated a sensitivity better than 0.001G for an applied magnetic field of $ \\sim 1$G and a good selectivity for the magnetic field direction. The sensitivity can be easily improved by a factor of $\\sim ...

  17. Finite Element Model of Training in the superconducting quadrupole magnet SQ02

    SciTech Connect (OSTI)

    Caspi, Shlomo; Ferracin, Paolo

    2007-11-01T23:59:59.000Z

    This paper describes the use of 3D finite element models to study training in superconducting magnets. The simulations are used to examine coil displacements when the electromagnetic forces are cycled, and compute the frictional energy released during conductor motion with the resulting temperature rise. A computed training curve is then presented and discussed. The results from the numerical computations are compared with test results of the Nb{sub 3}Sn racetrack quadrupole magnet SQ02.

  18. Journal of Magnetism and Magnetic Materials ] (

    E-Print Network [OSTI]

    McHenry, Michael E.

    magnetic properties were measured with a vibrating sample magnetometer. The mass-specific power loss.40.Rs Keywords: Nanocrystalline alloys; Amorphous alloys; Field annealing; Power loss; Soft magnets the hysteretic power loss while maintaining high-temperature operability [4]. Other goals have included studies

  19. Magnetic Materials Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for magnetic circular dichroism (XMCD) and magnetic scattering experiments. Sunset Yellow 6-ID-B: Resonant and In-Field Scattering Beamline 6-ID-B,C is the primary beamline on...

  20. Recent lunar magnetism

    E-Print Network [OSTI]

    Buz, Jennifer

    2011-01-01T23:59:59.000Z

    The magnetization of young lunar samples (magnetic fields (e.g. core dynamo and long-lived impact plasma fields) have not been present within the last 1.5 Ga. To better ...

  1. Active magnetic regenerator

    DOE Patents [OSTI]

    Barclay, John A. (Los Alamos, NM); Steyert, William A. (Los Alamos, NM)

    1982-01-01T23:59:59.000Z

    The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

  2. Magnetism Theory Group / POSTECH Magnetism Theory Group / POSTECH

    E-Print Network [OSTI]

    Min, Byung Il

    Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH #12;Magnetism Theory Group / POSTECH J.H . Park et al. #12;'s of FeinCsm e tal The chargeandorbitalordering geom etryin YB a C o 2 O 5 S. K. Kwon etal .Magnetism Theory

  3. Magnetic susceptibility in QCD

    E-Print Network [OSTI]

    V. D. Orlovsky; Yu. A. Simonov

    2014-05-12T23:59:59.000Z

    Magnetic susceptibility in the deconfined phase of QCD is calculated in a closed form using a recent general expression for the quark gas pressure in magnetic field. Quark selfenergies are entering the result via Polyakov line factors and ensure the total paramagnetic effect, increasing with temperature. A generalized form of magnetic susceptibility in nonzero magnetic field suitable for experimental and lattice measurements is derived, showing a good agreement with available lattice data.

  4. Diffusional motion of redox centers in carbonate electrolytes

    SciTech Connect (OSTI)

    Han, Kee Sung [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Rajput, Nav Nidhi; Persson, Kristin A. [Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Wei, Xiaoliang; Wang, Wei [Energy and Environmental Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Hu, Jian Zhi [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Mueller, Karl T., E-mail: karl.mueller@pnnl.gov [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2014-09-14T23:59:59.000Z

    Ferrocene (Fc) and N-(ferrocenylmethyl)-N,N-dimethyl-N-ethylammonium bistrifluoromethyl-sulfonimide (Fc1N112-TFSI) were dissolved in carbonate solvents and self-diffusion coefficients (D) of solutes and solvents were measured by {sup 1}H and {sup 19}F pulsed field gradient nuclear magnetic resonance (NMR) spectroscopy. The organic solvents were propylene carbonate (PC), ethyl methyl carbonate (EMC), and a ternary mixture that also includes ethylene carbonate (EC). Results from NMR studies over the temperature range of 0–50 °C and for various concentrations (0.25–1.7 M) of Fc1N112-TFSI are compared to values of D simulated with classical molecular dynamics (MD). The measured self-diffusion coefficients gradually decreased as the Fc1N112-TFSI concentration increased in all solvents. Since TFSI{sup ?} has fluoromethyl groups (CF{sub 3}), D{sub TFSI} could be measured separately and the values found are larger than those for D{sub Fc1N112} in all samples measured. The EC, PC, and EMC have the same D in the neat solvent mixture and when Fc is dissolved in EC/PC/EMC at a concentration of 0.2 M, probably due to the interactions between common carbonyl structures within EC, PC, and EMC. A difference in D (D{sub PC} < D{sub EC} < D{sub EMC}), and both a higher E{sub a} for translational motion and higher effective viscosity for PC in the mixture containing Fc1N112-TFSI reflect the interaction between PC and Fc1N112{sup +}, which is a relatively stronger interaction than that between Fc1N112{sup +} and other solvent species. In the EC/PC/EMC solution that is saturated with Fc1N112-TFSI, we find that D{sub PC} = D{sub EC} = D{sub EMC} and Fc1N112{sup +} and all components of the EC/PC/EMC solution have the same E{sub a} for translational motion, while the ratio D{sub EC/PC/EMC}/D{sub Fc1N112} is approximately 3. These results reflect the lack of available free volume for independent diffusion in the saturated solution. The Fc1N112{sup +} transference numbers lie around 0.4 and increase slightly as the temperature is increased in the PC and EMC solvents. The trends observed for D from simulations are in good agreement with experimental results and provide molecular level understanding of the solvation structure of Fc1N112-TFSI dissolved in EC/PC/EMC.

  5. Diffusional Motion of Redox Centers in Carbonate Electrolytes

    SciTech Connect (OSTI)

    Han, Kee Sung; Rajput, Nav Nidhi; Wei, Xiaoliang; Wang, Wei; Hu, Jian Z.; Persson, Kristin A.; Mueller, Karl T.

    2014-09-14T23:59:59.000Z

    Ferrocene (Fc) and N-(ferrocenylmethyl)-N,N-dimethyl-N-ethylammonium bistrifluoromethyl-sulfonimide (Fc1N112-TFSI) were dissolved in carbonate solvents and self diffusion coefficents (D) of solutes and solvents were measured by 1H and 19F pulsed field gradient (PFG) nuclear magnetic resonance (NMR) spectroscopy. The organic solvents were propylene carbonate (PC), ethyl methyl carbonate (EMC) and a ternary mixture that also includes ethylene carbonate (EC). Results from NMR studies over the temperature range of 0-50 °C and for various concentrations (0.25 - 1.7 M) of Fc1N112-TFSI are compared to values of D simulated with classical molecular dynamics (MD). The measured self-diffusion coefficients gradually decreased as the Fc1N112-TFSI concentration increased in all solvents. Since the peaks for the two ions (Fc1N212 and TFSI) are separated in one-dimensional NMR spectra, separate diffusion coefficients could be measured and DTFSI is larger than DFc1N112 in all samples measured. The EC, PC and EMC have the same D in the neat solvent mixture and when Fc is dissolved in EC/PC/EMC at a concentration of 0.2 M, probably due to the interactions between common carbonyl structures within EC, PC and EMC. A difference in D (DPC < DEC < DEMC), and both a higher Ea for translational motion and higher effective viscosity for PC in the mixture containing Fc1N112-TFSI reflect the interaction between PC and Fc1N112+, which is a relatively stronger interaction than that between Fc1N112+ and other solvent species. In the EC/PC/EMC solution that is saturated with Fc1N112-TFSI, we find that DPC = DEC = DEMC and Fc1N112+ and all components of the EC/PC/EMC solution have the same Ea for translational motion, while the ratio DEC/PC/EMC/DFc1N112+ is approximately 3. These results reflect the lack of available free volume for independent diffusion in the saturated solution. The Fc1N112+ transference numbers lie around 0.4 and increases slightly as the temperature is increased in the PC and EMC solvents. The trends observed for D from simulations are in good agreement with experimental results and provide molecular level understanding of the solvation structure of Fc1N112-TFSI dissolved in EC/PC/EMC.

  6. Noble gas magnetic resonator

    DOE Patents [OSTI]

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2014-04-15T23:59:59.000Z

    Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.

  7. Magnetic nanohole superlattices

    DOE Patents [OSTI]

    Liu, Feng

    2013-05-14T23:59:59.000Z

    A magnetic material is disclosed including a two-dimensional array of carbon atoms and a two-dimensional array of nanoholes patterned in the two-dimensional array of carbon atoms. The magnetic material has long-range magnetic ordering at a temperature below a critical temperature Tc.

  8. Visualizing Motion in Potential Wells* Pratibha Jolly

    E-Print Network [OSTI]

    Zollman, Dean

    , directly and plot the potential energy diagrams using a magnetic field sensor. The ease of measurement of potential #12;2 barriers and wells. The previous developers used a photo-interrupt and timing device for the sake of economy a single sensor was employed. Then, the experiment had to be repeated a large number

  9. LABORATORY V PREDICTING NON-REPETITIVE MOTION

    E-Print Network [OSTI]

    Minnesota, University of

    that you will be doing some of these laboratory problems before your lecturer addresses this material as a viscous fluid, beakers, a stopwatch, a meter stick, a balance, magnets, a video camera and a computer you know or can measure. Beginning with basic physics principles, show how you get an equation

  10. Atomistic Simulation of Slow Grain Boundary Motion

    SciTech Connect (OSTI)

    Deng Chuang; Schuh, Christopher A. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)

    2011-01-28T23:59:59.000Z

    Existing atomistic simulation techniques to study grain boundary motion are usually limited to either high velocities or temperatures and are difficult to compare to realistic experimental conditions. Here we introduce an adapted simulation method that can access boundary velocities in the experimental range and extract mobilities in the zero driving force limit at temperatures as low as {approx}0.2T{sub m} (T{sub m} is the melting point). The method reveals three mechanistic regimes of boundary mobility at zero net velocity depending on the system temperature.

  11. Casimir friction: Relative motion more generally

    E-Print Network [OSTI]

    Johan S. Høye; Iver Brevik

    2014-09-23T23:59:59.000Z

    This paper extends our recent study on Casimir friction forces for dielectric plates moving parallel to each other [J. S. H{\\o}ye and I. Brevik, Eur. Phys. J. D {\\bf 68}, 61 (2014)], to the case where the plates are no longer restricted to rectilinear motion. Part of the mathematical formalism thereby becomes more cumbersome, but reduces in the end to the form that we could expect to be the natural one in advance. As an example, we calculate the Casimir torque on a planar disc rotating with constant angular velocity around its vertical symmetry axis next to another plate.

  12. Soret Motion of a Charged Spherical Colloid

    E-Print Network [OSTI]

    Seyyed Nader Rasuli; Ramin Golestanian

    2008-08-05T23:59:59.000Z

    The thermophoretic motion of a charged spherical colloidal particle and its accompanying cloud of counterions and co-ions in a temperature gradient is studied theoretically. Using the Debye-Huckel approximation, the Soret drift velocity of a weakly charged colloid is calculated analytically. For highly charged colloids, the nonlinear system of electrokinetic equations is solved numerically, and the effects of high surface potential, dielectrophoresis, and convection are examined. Our results are in good agreement with some of the recent experiments on highly charged colloids without using adjustable parameters.

  13. Collective motion in a Hamiltonian dynamical system

    E-Print Network [OSTI]

    Hidetoshi Morita; Kunihiko Kaneko

    2005-06-11T23:59:59.000Z

    Oscillation of macroscopic variables is discovered in a metastable state in the Hamiltonian dynamical system of mean field XY model, the duration of which is divergent with the system size. This long-lasting periodic or quasiperiodic collective motion appears through Hopf bifurcation, which is a typical route in low-dimensional dissipative dynamical systems. The origin of the oscillation is explained, with self-consistent analysis of the distribution function, as the emergence of self-excited ``swings'' through the mean-field. The universality of the phenomena is also discussed.

  14. The equation of motion of an electron

    SciTech Connect (OSTI)

    Kim, K. [Argonne National Laboratory, Argonne, Illinois 60439 and The University of Chicago, Chicago, Illinois 60637 (United States); Sessler, A.M. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    1999-07-01T23:59:59.000Z

    We review the current status of understanding of the equation of motion of an electron. Classically, a consistent, linearized theory exists for an electron of finite extent, as long as the size of the electron is larger than the classical electron radius. Nonrelativistic quantum mechanics seems to offer a fine theory even in the point particle limit. Although there is as yet no convincing calculation, it is probable that a quantum electrodynamical result will be at least as well-behaved as is the nonrelativistic quantum mechanical results. {copyright} {ital 1999 American Institute of Physics.}

  15. The equation of motion of an electron.

    SciTech Connect (OSTI)

    Kim, K.-J.

    1998-09-02T23:59:59.000Z

    We review the current status of understanding of the equation of motion of an electron. Classically, a consistent linearized theory exists for an electron of finite extent, as long as the size of the electron is larger than the classical electron radius. Nonrelativistic quantum mechanics seems to offer a fine theory even in the point particle limit. Although there is as yet no convincing calculation, it is probable that a quantum electrodynamical result will be at least as well-behaved as is the nonrelativistic quantum mechanical results.

  16. Quantization of singular systems and incomplete motions

    E-Print Network [OSTI]

    N. P. Landsman

    1998-07-24T23:59:59.000Z

    The need for a mathematically rigorous quantization procedure of singular spaces and incomplete motions is pointed out in connection with quantum cosmology. We put our previous suggestion for such a procedure, based on the theory of induced representations of C*-algebras, in the light of L. Schwartz' theory of Hilbert subspaces. This turns out to account for the freedom in the induction procedure, at the same time providing a basis for generalized eigenfunction expansions pertinent to the needs of quantum cosmology. Reinforcing our previous proposal for the wave-function of the Universe, we are now able to add a concrete prescription for its calculation.

  17. Quantum potential energy as concealed motion

    E-Print Network [OSTI]

    Peter Holland

    2014-11-13T23:59:59.000Z

    It is known that the Schroedinger equation may be derived from a hydrodynamic model in which the Lagrangian position coordinates of a continuum of particles represent the quantum state. Using Routh\\s method of ignorable coordinates it is shown that the quantum potential energy of particle interaction that represents quantum effects in this model may be regarded as the kinetic energy of additional concealed freedoms. The method brings an alternative perspective to Planck\\s constant, which plays the role of a hidden variable, and to the canonical quantization procedure, since what is termed kinetic energy in quantum mechanics may be regarded literally as energy due to motion.

  18. Relativistic Brownian motion on a graphene chip

    E-Print Network [OSTI]

    Andrey Pototsky; Fabio Marchesoni; Feodor V. Kusmartsev; Peter Hänggi; Sergey E. Savel'ev

    2012-02-28T23:59:59.000Z

    Relativistic Brownian motion can be inexpensively demonstrated on a graphene chip. The interplay of stochastic and relativistic dynamics, governing the transport of charge carrier in graphene, induces noise-controlled effects such as (i) a stochastic effective mass, detectable as a suppression of the particle mobility with increasing the temperature; (ii) a transverse ratchet effect, measurable as a net current orthogonal to an ac drive on an asymmetric substrate, and (iii) a chaotic stochastic resonance. Such properties can be of practical applications in the emerging graphene technology.

  19. Blue Motion Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:EzfeedflagBiomass ConversionsSouthby 2022 |BleckleyMotion Energy Jump to: navigation, search

  20. Danotek Motion Technologies | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:PowerCER.pngRoofs andCrops Ltd Jump1-EA JumpDalyDanotek Motion

  1. Ultra-high-resolution Observations of MHD Waves in Photospheric Magnetic Structures

    E-Print Network [OSTI]

    Jess, David B

    2015-01-01T23:59:59.000Z

    Here we review the recent progress made in the detection, examination, characterisation and interpretation of oscillations manifesting in small-scale magnetic elements in the solar photosphere. This region of the Sun's atmosphere is especially dynamic, and importantly, permeated with an abundance of magnetic field concentrations. Such magnetic features can span diameters of hundreds to many tens of thousands of km, and are thus commonly referred to as the `building blocks' of the magnetic solar atmosphere. However, it is the smallest magnetic elements that have risen to the forefront of solar physics research in recent years. Structures, which include magnetic bright points, are often at the diffraction limit of even the largest of solar telescopes. Importantly, it is the improvements in facilities, instrumentation, imaging techniques and processing algorithms during recent years that have allowed researchers to examine the motions, dynamics and evolution of such features on the smallest spatial and temporal ...

  2. Magnetically attached sputter targets

    DOE Patents [OSTI]

    Makowiecki, D.M.; McKernan, M.A.

    1994-02-15T23:59:59.000Z

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

  3. Formation of Moving Magnetic Features and Penumbral Magnetic Fields with Hinode/SOT

    E-Print Network [OSTI]

    Masahito Kubo; Kiyoshi Ichimoto; Toshifumi Shimizu; Saku Tsuneta; Yoshinori Suematsu; Yukio Katsukawa; Shin'ichi Nagata; Theodore D Tarbell; Richard A Shine; Alan M Title; Zoe A Frank; Bruce W Lites; David Elmore

    2007-09-12T23:59:59.000Z

    Vector magnetic fields of moving magnetic features (MMFs) are well observed with the Solar Optical Telescope (SOT) aboard the Hinode satellite. We focus on the evolution of three MMFs with the SOT in this study. We found that an MMF having relatively vertical fields with polarity same as the sunspot is detached from the penumbra around the granules appeared in the outer penumbra. This suggests that granular motions in the outer penumbra are responsible for the disintegration of the sunspot. Two MMFs with polarity opposite to the sunspot are located around the outer edge of horizontal fields extending from the penumbra. This is an evidence that the MMFs with polarity opposite to the sunspot are prolongation of penumbral horizontal fields. Radshifts larger than sonic velocity in the photosphere are detected for some of the MMFs with polarity opposite to the sunspot.

  4. Multi-camera Tracking of Articulated Human Motion Using Motion and Shape Cues

    E-Print Network [OSTI]

    Sundaresan, Aravind

    of this energy image. We can then obtain the pose that possesses the least energy using optimisation P cameras and an articulated human shape model. Tracking is performed using motion cues as well as image multi-scale parametric optimisation to estimate the pixel displacement for each body segment. We

  5. Motion Patches: Building Blocks for Virtual Environments Annotated with Motion Data

    E-Print Network [OSTI]

    Lee, Jehee

    time animation of human figures in virtual environments is an important problem in the context-Dimensional Graphics and Realism]: Animation--Virtual reality Keywords: Interactive character animation, human motion:{zoi,mingle,jehee}@mrl.snu.ac.kr The real time animation and control of human figures in complex virtual environments have been an important

  6. The chiral magnetic nanomotors

    E-Print Network [OSTI]

    Morozov, Konstantin I

    2013-01-01T23:59:59.000Z

    Propulsion of the chiral magnetic nanomotors powered by a rotating magnetic field is in the focus of the modern biomedical applications. This technology relies on strong interaction of dynamic and magnetic degrees of freedom of the system. Here we study in detail various experimentally observed regimes of the helical nanomotor orientation and propulsion depending on the actuation frequency, and establish the relation of these two properties with remanent magnetization and geometry of the helical nanomotors. The theoretical predictions for the transition between the regimes and nanomotor orientation and propulsion speed are in excellent agreement with available experimental data. The proposed theory offers a few simple guidelines towards the optimal design of the magnetic nanomotors. In particular, efficient nanomotors should be fabricated of hard magnetics, e.g., cobalt, magnetized transversally and have the geometry of a normal helix with a helical angle of 35-45 degrees.

  7. Lorentz transformations with arbitrary line of motion

    E-Print Network [OSTI]

    Chandru Iyer; G. M. Prabhu

    2008-09-18T23:59:59.000Z

    Sometimes it becomes a matter of natural choice for an observer (A) that he prefers a coordinate system of two-dimensional spatial x-y coordinates from which he observes another observer (B) who is moving at a uniform speed along a line of motion, which is not collinear with As chosen x or y axis. It becomes necessary in such cases to develop Lorentz transformations where the line of motion is not aligned with either the x or the y-axis. In this paper we develop these transformations and show that under such transformations, two orthogonal systems (in their respective frames) appear non-orthogonal to each other. We also illustrate the usefulness of the transformation by applying it to three problems including the rod-slot problem. The derivation has been done before using vector algebra. Such derivations assume that the axes of K and K-prime are parallel. Our method uses matrix algebra and shows that the axes of K and K-prime do not remain parallel, and in fact K and K-prime which are properly orthogonal are observed to be non-orthogonal by K-prime and K respectively. http://www.iop.org/EJ/abstract/0143-0807/28/2/004

  8. Motion Measurement for Synthetic Aperture Radar.

    SciTech Connect (OSTI)

    Doerry, Armin W.

    2015-01-01T23:59:59.000Z

    Synthetic Aperture Radar (SAR) measures radar soundings from a set of locations typically along the flight path of a radar platform vehicle. Optimal focusing requires precise knowledge of the sounding source locations in 3 - D space with respect to the target scene. Even data driven focusing techniques (i.e. autofocus) requires some degree of initial fidelity in the measurements of the motion of the radar. These requirements may be quite stringent especially for fine resolution, long ranges, and low velocities. The principal instrument for measuring motion is typically an Inertial Measurement Unit (IMU), but these instruments have inherent limi ted precision and accuracy. The question is %22How good does an IMU need to be for a SAR across its performance space?%22 This report analytically relates IMU specifications to parametric requirements for SAR. - 4 - Acknowledgements Th e preparation of this report is the result of a n unfunded research and development activity . Although this report is an independent effort, it draws heavily from limited - release documentation generated under a CRADA with General Atomics - Aeronautical System, Inc. (GA - ASI), and under the Joint DoD/DOE Munitions Program Memorandum of Understanding. Sandia National Laboratories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of En ergy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000.

  9. Charged spinning fluids with magnetic dipole moment in the Einstein-Cartan theory

    SciTech Connect (OSTI)

    Amorim, R.

    1985-06-15T23:59:59.000Z

    A classical perfect charged spinning fluid with magnetic dipole moment in the Einstein-Cartan theory is described by using an Eulerian Lagrangian formalism. The field equations and equations of motion so obtained generalize those proposed by Ray and Smalley. We also clarify some open questions which appear in the works of Ray and Smalley and of de Ritis et al.

  10. Bipolar magnetic structures driven by stratified turbulence with a coronal Jorn Warnecke1,2

    E-Print Network [OSTI]

    Brandenburg, Axel

    regions is also an ingredient in some dynamo theories to explain the 22-year cyclic behavior of the solar convective motions. Therefore, sunspots appear dark on the solar disk. We are nowadays able to study them with #12;­ 2 ­ Fig. 1.-- Left panel: normalized vertical magnetic field Bz/Beq of the bipolar region

  11. Bipolar magnetic structures driven by stratified turbulence with a coronal Jorn Warnecke1,2

    E-Print Network [OSTI]

    Brandenburg, Axel

    regions is also an ingredient in some dynamo theories to explain the 22-year cyclic behavior of the solar convective motions and appear therefore dark on the solar disk. We are nowadays able to study them with high resolution #12;­ 2 ­ Fig. 1.-- Left panel: normalized vertical magnetic field Bz/Beq of the bipolar region

  12. Morphology of the Small-Animal Lung Using Magnetic Resonance Microscopy

    E-Print Network [OSTI]

    Morphology of the Small-Animal Lung Using Magnetic Resonance Microscopy Laurence W. Hedlund and G motion control and animal support, the lungs of the live, small animal can be imaged. Although in vivo He, it is possible to image the tissue and gas compartments of the lung. This capability

  13. Motion of spinning test bodies in Kerr spacetime

    E-Print Network [OSTI]

    Eva Hackmann; Claus Lämmerzahl; Yuri N. Obukhov; Dirk Puetzfeld; Isabell Schaffer

    2014-09-23T23:59:59.000Z

    We investigate the motion of spinning test bodies in General Relativity. By means of a multipolar approximation method for extended test bodies we derive the equations of motion, and classify the orbital motion of pole-dipole test bodies in the equatorial plane of the Kerr geometry. An exact expression for the periastron shift of a spinning test body is given. Implications of test body spin corrections are studied and compared with the results obtained by means of other approximation schemes.

  14. Bulgarian Verbs of Motion: Slavic Verbs in a Balkan Context

    E-Print Network [OSTI]

    Lindsey, Traci Speed

    2011-01-01T23:59:59.000Z

    Jouko. 2000. Is there a Balkan verb system? In Milato South Slavic and Balkan Languages, Plovdiv Septemberof Motion: Slavic Verbs in a Balkan Context by Traci Speed

  15. Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles

    E-Print Network [OSTI]

    Smith, Ryan N.

    Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles Monique Chyba and energy minimization for AUVs). A major difficulty is to provide a formal estimation that compares

  16. Notes on the two-dimensional fractional Brownian motion

    E-Print Network [OSTI]

    Fabrice Baudoin , David Nualart

    2006-02-09T23:59:59.000Z

    Theory Related Fields 118 121–291. [12] PITMAN, J. and YOR, M. (1986). Asymptotic laws of planar Brownian motion. Ann. Probab. 14 733–779. [13] PITMAN ...

  17. Real Time Estimation of Ship Motions Using Kalman Filtering Techniques

    E-Print Network [OSTI]

    Triantafyllou, Michael S.

    1983-01-01T23:59:59.000Z

    The estimation of the heave, pitch, roll, sway, and yaw motions of a DD-963 destroyer is studied, using Kalman filtering

  18. Wall and laser spot motion in cylindrical hohlraums

    SciTech Connect (OSTI)

    Huser, G.; Courtois, C.; Monteil, M.-C. [CEA, DAM, DIF, F-91297 Arpajon (France)

    2009-03-15T23:59:59.000Z

    Wall and laser spot motion measurements in empty, propane-filled and plastic (CH)-lined gold coated cylindrical hohlraums were performed on the Omega laser facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. Wall motion was measured using axial two-dimensional (2D) x-ray imaging and laser spot motion was perpendicularly observed through a thinned wall using streaked hard x-ray imaging. Experimental results and 2D hydrodynamic simulations show that while empty targets exhibit on-axis plasma collision, CH-lined and propane-filled targets inhibit wall expansion, corroborated with perpendicular streaked imaging showing a slower motion of laser spots.

  19. Free motion in deformed (quantum) four-dimensional space

    E-Print Network [OSTI]

    A. N. Leznov

    2007-07-23T23:59:59.000Z

    It is shown that trajectories of free motion of the particles in deformed ("quantum") four dimensional space-time are quadratic curves.

  20. Adaptive motion mapping in pancreatic SBRT patients using Fourier transforms

    E-Print Network [OSTI]

    Jones, Bernard L; Miften, Moyed

    2015-01-01T23:59:59.000Z

    Recent studies suggest that 4DCT is unable to accurately measure respiratory-induced pancreatic tumor motion. In this work, we assessed the daily motion of pancreatic tumors treated with SBRT, and developed adaptive strategies to predict and account for this motion. The daily motion trajectory of pancreatic tumors during CBCT acquisition was calculated using a model which reconstructs the instantaneous 3D position in each 2D CBCT projection image. We developed a metric (termed "Spectral Coherence," SC) based on the Fourier frequency spectrum of motion in the SI direction, and analyzed the ability of SC to predict motion-based errors and classify patients according to motion characteristics. The amplitude of daily motion exceeded the predictions of pre-treatment 4DCT imaging by an average of 3.0 mm, 2.3 mm, and 3.5 mm in the AP, LR, and SI directions. SC was correlated with daily motion differences and tumor dose coverage. In a simulated adaptive protocol, target margins were adjusted based on SC, resulting in...

  1. adaptive head motion: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and performs principal ... Balakrishnan, Guha 2014-01-01 7 Computational Modeling of Brain Dynamics during Repetitive Head Motions Computer Technologies and Information...

  2. amplitude rotational motion: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    motion can help constrain the mass distribution inside the body, which in turn can lead to information on its geophysical history. Aims. We investigate the signature of the...

  3. artery rotational motion: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    motion can help constrain the mass distribution inside the body, which in turn can lead to information on its geophysical history. Aims. We investigate the signature of the...

  4. External magnetic field influence on H{sub {alpha}} line in abnormal glow discharge

    SciTech Connect (OSTI)

    Obradovic, B.M.; Dojcinovic, I.P.; Kuraica, M.M.; Puric, J. [Faculty of Physics, University of Belgrade, P.O. Box 368, 11001 Belgrade (Serbia and Montenegro) and Center for Science and Development of Technology, Obilicev Venac 26, 11001 Belgrade (Serbia and Montenegro)

    2006-04-03T23:59:59.000Z

    Influence of the external axial magnetic field on the hydrogen H{sub {alpha}} line profiles in an abnormal glow discharge has been studied. It has been found that the applied magnetic field predominantly increases the intensity of central component of the characteristic excessively broadened H{sub {alpha}} profile. Magnetic filed causes helical motion of electrons along the electric field lines and prolongs their trajectories increasing the number of collisions with matrix gas. This explains the increase of the central component of H{sub {alpha}} profile and can be regarded as an experimental proof for the main contribution of electron excitation to that part of the profile.

  5. Heating of the magnetized solar chromosphere by partial ionization effects

    E-Print Network [OSTI]

    Khomenko, Elena

    2011-01-01T23:59:59.000Z

    In this paper, we study the heating of the magnetized solar chromosphere induced by the large fraction of neutral atoms present in this layer. The presence of neutrals, together with the decrease with height of the collisional coupling, leads to deviations from the classical MHD behavior of the chromospheric plasma. A relative net motion appears between the neutral and ionized components, usually referred to as ambipolar diffusion. The dissipation of currents in the chromosphere is enhanced orders of magnitude due to the action of ambipolar diffusion, as compared to the standard ohmic diffusion. We propose that a significant amount of magnetic energy can be released to the chromosphere just by existing force-free 10--40 G magnetic fields there. As a consequence, we conclude that ambipolar diffusion is an important process that should be included in chromospheric heating models, as it has the potential to rapidly heat the chromosphere. We perform analytical estimations and numerical simulations to prove this i...

  6. Magnetic Fields in Population III Star Formation

    SciTech Connect (OSTI)

    Turk, Matthew J.; Oishi, Jeffrey S.; Abel, Tom; Bryan, Greg

    2012-02-22T23:59:59.000Z

    We study the buildup of magnetic fields during the formation of Population III star-forming regions, by conducting cosmological simulations from realistic initial conditions and varying the Jeans resolution. To investigate this in detail, we start simulations from identical initial conditions, mandating 16, 32 and 64 zones per Jeans length, and studied the variation in their magnetic field amplification. We find that, while compression results in some amplification, turbulent velocity fluctuations driven by the collapse can further amplify an initially weak seed field via dynamo action, provided there is sufficient numerical resolution to capture vortical motions (we find this requirement to be 64 zones per Jeans length, slightly larger than, but consistent with previous work run with more idealized collapse scenarios). We explore saturation of amplification of the magnetic field, which could potentially become dynamically important in subsequent, fully-resolved calculations. We have also identified a relatively surprising phenomena that is purely hydrodynamic: the higher-resolved simulations possess substantially different characteristics, including higher infall-velocity, increased temperatures inside 1000 AU, and decreased molecular hydrogen content in the innermost region. Furthermore, we find that disk formation is suppressed in higher-resolution calculations, at least at the times that we can follow the calculation. We discuss the effect this may have on the buildup of disks over the accretion history of the first clump to form as well as the potential for gravitational instabilities to develop and induce fragmentation.

  7. Design and Characterization of a Field-Switchable Nanomagnetic Atom Mirror

    E-Print Network [OSTI]

    Hayward, T J; Weatherill, K J; Curran, P J; Fry, P W; Fundi, P M; Gibbs, M R J; Schrefl, T; Adams, C S; Hughes, I G; Bending, S J; Allwood, D A

    2010-01-01T23:59:59.000Z

    We present a design for a switchable nanomagnetic atom mirror formed by an array of 180{\\deg} domain walls confined within Ni80Fe20 planar nanowires. A simple analytical model is developed which allows the magnetic field produced by the domain wall array to be calculated. This model is then used to optimize the geometry of the nanowires so as to maximize the reflectivity of the atom mirror. We then describe the fabrication of a nanowire array and characterize its magnetic behavior using magneto-optic Kerr effect magnetometry, scanning Hall probe microscopy and micromagnetic simulations, demonstrating how the mobility of the domain walls allow the atom mirror to be switched "on" and "off" in a manner which would be impossible for conventional designs. Finally, we model the reflection of 87Rb atoms from the atom mirror's surface, showing that our design is well suited for investigating interactions between domain walls and cold atoms.

  8. Josephson junction of non-Abelian superconductors and non-Abelian Josephson vortices

    E-Print Network [OSTI]

    Nitta, Muneto

    2015-01-01T23:59:59.000Z

    A Josephson junction is made of two superconductors sandwiching an insulator, and a Josephson vortex is a magnetic vortex absorbed into the Josephson junction, whose dynamics can be described by the sine-Gordon equation. In a field theory framework, a flexible Josephson junction was proposed, in which the Josephson junction is represented by a domain wall separating two condensations and a Josephson vortex is a sine-Gordon soliton in the domain wall effective theory. In this paper, we propose a Josephson junction of non-Abelian color superconductors, that is described by a non-Abelian domain wall, and show that a non-Abelian vortex (color magnetic flux tube) absorbed into it is a non-Abelian Josephson vortex represented as a non-Abelian sine-Gordon soliton in the domain wall effective theory.

  9. Handling congestion in crowd motion modeling

    E-Print Network [OSTI]

    Maury, B; Santambrogio, F; Venel, J

    2011-01-01T23:59:59.000Z

    We address here the issue of congestion in the modeling of crowd motion, in the non-smooth framework: contacts between people are not anticipated and avoided, they actually occur, and they are explicitly taken into account in the model. We limit our approach to very basic principles in terms of behavior, to focus on the particular problems raised by the non-smooth character of the models. We consider that individuals tend to move according to a desired, or spontanous, velocity. We account for congestion by assuming that the evolution realizes at each time an instantaneous balance between individual tendencies and global constraints (overlapping is forbidden): the actual velocity is defined as the closest to the desired velocity among all admissible ones, in a least square sense. We develop those principles in the microscopic and macroscopic settings, and we present how the framework of Wasserstein distance between measures allows to recover the sweeping process nature of the problem on the macroscopic level, ...

  10. Solid state engine with alternating motion

    DOE Patents [OSTI]

    Golestaneh, Ahmad A. (Bolingbrook, IL)

    1982-01-01T23:59:59.000Z

    Heat energy is converted to mechanical motion utilizing apparatus including a cylinder, a piston having openings therein reciprocable in the cylinder, inlet and outlet ports for warm water at one end of the cylinder, inlet and outlet ports for cool water at the other end of the cylinder, gates movable with the piston and slidably engaging the cylinder wall to alternately open and close the warm and cool water ports, a spring bearing against the warm water side of the piston and a double helix of a thermal shape memory material attached to the cool end of the cylinder and to the piston. The piston is caused to reciprocate by alternately admitting cool water and warm water to the cylinder.

  11. Minimum and terminal velocities in projectile motion

    E-Print Network [OSTI]

    E. N. Miranda; S. Nikolskaya; R. Riba

    2012-08-13T23:59:59.000Z

    The motion of a projectile with horizontal initial velocity V0, moving under the action of the gravitational field and a drag force is studied analytically. As it is well known, the projectile reaches a terminal velocity Vterm. There is a curious result concerning the minimum speed Vmin; it turns out that the minimum velocity is lower than the terminal one if V0 > Vterm and is lower than the initial one if V0 < Vterm. These results show that the velocity is not a monotonous function. If the initial speed is not horizontal, there is an angle range where the velocity shows the same behavior mentioned previously. Out of that range, the volocity is a monotonous function. These results come out from numerical simulations.

  12. Granular Brownian motion with dry friction

    E-Print Network [OSTI]

    A. Gnoli; A. Puglisi; H. Touchette

    2013-04-12T23:59:59.000Z

    The interplay between Coulomb friction and random excitations is studied experimentally by means of a rotating probe in contact with a stationary granular gas. The granular material is independently fluidized by a vertical shaker, acting as a 'heat bath' for the Brownian-like motion of the probe. Two ball bearings supporting the probe exert nonlinear Coulomb friction upon it. The experimental velocity distribution of the probe, autocorrelation function, and power spectra are compared with the predictions of a linear Boltzmann equation with friction, which is known to simplify in two opposite limits: at high collision frequency, it is mapped to a Fokker-Planck equation with nonlinear friction, whereas at low collision frequency, it is described by a sequence of independent random kicks followed by friction-induced relaxations. Comparison between theory and experiment in these two limits shows good agreement. Deviations are observed at very small velocities, where the real bearings are not well modeled by Coulomb friction.

  13. Data Combinations Accounting for LISA Spacecraft Motion

    E-Print Network [OSTI]

    Daniel A. Shaddock; Massimo Tinto; Frank B. Estabrook; J. W. Armstrong

    2003-07-16T23:59:59.000Z

    LISA is an array of three spacecraft in an approximately equilateral triangle configuration which will be used as a low-frequency gravitational wave detector. We present here new generalizations of the Michelson- and Sagnac-type time-delay interferometry data combinations. These combinations cancel laser phase noise in the presence of different up and down propagation delays in each arm of the array, and slowly varying systematic motion of the spacecraft. The gravitational wave sensitivities of these generalized combinations are the same as previously computed for the stationary cases, although the combinations are now more complicated. We introduce a diagrammatic representation to illustrate that these combinations are actually synthesized equal-arm interferometers.

  14. Solid state engine with alternating motion

    DOE Patents [OSTI]

    Golestaneh, A.A.

    1980-01-21T23:59:59.000Z

    Heat energy is converted to mechanical motion utilizing apparatus including a cylinder, a piston having openings therein reciprocable in the cylinder, inlet and outlet ports for warm water at one end of the cylinder, inlet and outlet ports for cool water at the other end of the cylinder, gates movable with the piston and slidably engaging the cylinder wall to alternately open and close the warm and cool water ports, a spring bearing against the warm water side of the piston and a double helix of a thermal shape memory material attached to the cool end of the cylinder and to the piston. The piston is caused to reciprocate by alternately admitting cool water and warm water to the cylinder.

  15. Passive magnetic bearing system

    DOE Patents [OSTI]

    Post, Richard F.

    2014-09-02T23:59:59.000Z

    An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

  16. Pulse magnetic welder

    DOE Patents [OSTI]

    Christiansen, D.W.; Brown, W.F.

    1984-01-01T23:59:59.000Z

    A welder is described for automated closure of fuel pins by a pulsed magnetic process in which the open end of a length of cladding is positioned within a complementary tube surrounded by a pulsed magnetic welder. Seals are provided at each end of the tube, which can be evacuated or can receive tag gas for direct introduction to the cladding interior. Loading of magnetic rings and end caps is accomplished automatically in conjunction with the welding steps carried out within the tube.

  17. Magnetic latching solenoid

    DOE Patents [OSTI]

    Marts, Donna J. (Idaho Falls, ID); Richardson, John G. (Idaho Falls, ID); Albano, Richard K. (Idaho Falls, ID); Morrison, Jr., John L. (Idaho Falls, ID)

    1995-01-01T23:59:59.000Z

    This invention discloses a D.C. magnetic latching solenoid that retains a moving armature in a first or second position by means of a pair of magnets, thereby having a zero-power requirement after actuation. The first or second position is selected by reversing the polarity of the D.C. voltage which is enough to overcome the holding power of either magnet and transfer the armature to an opposite position. The coil is then de-energized.

  18. Holographic Magnetic Phase Transition

    E-Print Network [OSTI]

    Gilad Lifschytz; Matthew Lippert

    2009-06-21T23:59:59.000Z

    We study four-dimensional interacting fermions in a strong magnetic field, using the holographic Sakai-Sugimoto model of intersecting D4 and D8 branes in the deconfined, chiral-symmetric parallel phase. We find that as the magnetic field is varied, while staying in the parallel phase, the fermions exhibit a first-order phase transition in which their magnetization jumps discontinuously. Properties of this transition are consistent with a picture in which some of the fermions jump to the lowest Landau level. Similarities to known magnetic phase transitions are discussed.

  19. Magnetic Braids Anthony Yeates

    E-Print Network [OSTI]

    Dundee, University of

    flux function Main result Conclusion 2. Thermonuclear confinement devices. ITER (Internat'l Thermonuclear Experimental Reactor). Inside the KSTAR tokamak. Correspond to periodic magnetic braids. 4 / 22

  20. Nonthermally Dominated Electron Acceleration during Magnetic Reconnection in a Low-beta Plasma

    E-Print Network [OSTI]

    Li, Xiaocan; Li, Hui; Li, Gang

    2015-01-01T23:59:59.000Z

    By means of fully kinetic simulations, we show that magnetic reconnection is highly efficient at converting magnetic energy into nonthermal electrons in the nonrelativistic low-beta regimes. This leads to a nonthermally dominated distribution with a power-law tail that contains more than half of the electrons in the system. The main acceleration mechanism is a Fermi-type acceleration accomplished by the curvature drift motion along the electric field induced by Alfv\\'enic plasma flows. A guiding-center description is used to reveal the role of drift motions during the bulk nonthermal energization. The nonthermally dominated acceleration resulting from magnetic reconnection may help explain the highly efficient electron acceleration in solar flares and other astrophysical systems.

  1. Control strategies and motion planning for nanopositioning applications with multi-axis magnetic-levitation instruments

    E-Print Network [OSTI]

    Shakir, Huzefa

    2007-09-17T23:59:59.000Z

    comprised analytical design and development, followed by experimental verification and validation. Preliminary analysis and testing included open-loop stabilization and rigorous set-point change and load-change testing to demonstrate the precision...

  2. People Tracking with Human Motion Predictions from Social Forces

    E-Print Network [OSTI]

    Arras, Kai O.

    People Tracking with Human Motion Predictions from Social Forces Matthias Luber Johannes A. Stork Gian Diego Tipaldi Kai O. Arras Abstract-- For many tasks in populated environ- ments, robots need to keep track of current and future motion states of people. Most approaches to people tracking make weak

  3. Roadmap-based Motion Planning in Dynamic Environments

    E-Print Network [OSTI]

    Utrecht, Universiteit

    Roadmap-based Motion Planning in Dynamic Environments Jur P. van den Berg Mark H. Overmars.cs.uu.nl #12;Roadmap-based Motion Planning in Dynamic Environments Jur P. van den Berg Mark H. Overmars April obstacles. We propose a practical algorithm based on a roadmap that is created for the static part

  4. Robot Hand-Eye Calibration using Structure-from-Motion

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Robot Hand-Eye Calibration using Structure-from-Motion Nicolas Andre Radu Horaud Bernard Espiau procedure for hand- eye calibration. Indeed, no more calibration jig is needed and small calibration motions. This spatial relationship is a rigid transformation, a rotation and a translation, known as the hand-eye

  5. Kinodynamic Motion Planning by Interior-Exterior Cell Exploration

    E-Print Network [OSTI]

    Kavraki, Lydia E.

    Kinodynamic Motion Planning by Interior-Exterior Cell Exploration Ioan A. S¸ucan1 and Lydia E presents a kinodynamic motion planner, Kinodynamic Mo- tion Planning by Interior-Exterior Cell Exploration is necessary. A multiple-level grid-based discretization is used to estimate the coverage of the state space

  6. Learning Motion Primitives of Object Manipulation Using Mimesis Model

    E-Print Network [OSTI]

    Bryson, Joanna J.

    Learning Motion Primitives of Object Manipulation Using Mimesis Model Bidan Huang1, Joanna Bryson1 manipulation function. After modeling each primitive, the whole task then can be achieved by coordinating them- tion primitives are modeled as a set of differential equations or control rules. New motions

  7. MOTION OF ELECTRON-HOLE DROPS IN Ge

    E-Print Network [OSTI]

    Westervelt, R.M.

    2011-01-01T23:59:59.000Z

    MOTION OF ELECTRON-HOLE DROPS IN Ge R. M. Westervelt, J. C.MOTION OF ELECTRON-HOLE DROPS IN Ge R. M. Westervelt, J. C.OF ELECTRON-HOLE DROPS IN Ge R M Westervelt, J C Culbertson

  8. Creating Robust Roadmaps for Motion Planning in Changing Environments

    E-Print Network [OSTI]

    van den Berg, Jur

    Creating Robust Roadmaps for Motion Planning in Changing Environments Jur P. van den Berg1 Dennis-- In this paper we introduce a method based on the Probabilistic Roadmap (PRM) Planner to construct robust roadmaps for motion planning in changing environments. PRM's are usually aimed at static environments

  9. Creating Highquality Roadmaps for Motion Planning in Virtual Environments

    E-Print Network [OSTI]

    Geraerts, R.J.

    Creating High­quality Roadmaps for Motion Planning in Virtual Environments Roland Geraerts and Mark, the Netherlands Email: {roland,markov}@cs.uu.nl Abstract--- Our goal is to create roadmaps that are particularly suited for motion planning in virtual environments. We use our Reachability Roadmap Method to compute

  10. Motion Planning Using Dynamic Roadmaps Marcelo Kallmann and Maja Mataric

    E-Print Network [OSTI]

    Mataric, Maja J.

    Motion Planning Using Dynamic Roadmaps Marcelo Kallmann and Maja Mataric Interaction Lab, Computer, mataric}@usc.edu Abstract - We evaluate the use of dynamic roadmaps for on- line motion planning and nodes of a precomputed roadmap are updated accordingly. We concentrate in this paper on analyzing

  11. Risk based motion planning and navigation in uncertain dynamic environment

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Risk based motion planning and navigation in uncertain dynamic environment Chiara Fulgenzi, Anne of the dynamic environments. Moving obstacles are supposed to move along typical motion patterns represented the performance for a robotic wheelchair in a simulated environment among multiple dynamic obstacles. Index Terms

  12. Ideal Observers for Detecting Human Motion: Correspondence Noise.

    E-Print Network [OSTI]

    Yuille, Alan L.

    purpose, models of motion. We perform more psychophysical experiments which are consistent with humansIdeal Observers for Detecting Human Motion: Correspondence Noise. HongJing Lo Department obtain Barlow and Tripathy's classic model as an approximation. Our psychophysical experiments show

  13. Motion Sensor Driven Gestrure Recognition for Future Internet Application Development

    E-Print Network [OSTI]

    Petrakis, Euripides G.M.

    for motion sensor driven gesture recognition systems utilizing cloud technology and the FI- WARE core for training, monitoring movements, rehabilitation actions as well as educating purposes. In this work we focus and a motion sensor API for transforming specific hand language and gestures into system commands. The system

  14. Presentation entitled Fluid motion in a cylindrical container subject to

    E-Print Network [OSTI]

    Shihadeh, Alan

    developing a 3D motion out of the 2D . 2D von Karman Vortex street clouds Experimental investigations urged Karman Vortex street clouds To investigate experimentally the 2D vs. quasi-2D aspects, a table top: In the atmosphere and even the oceans the vortex motion is 2D as long as the thickness layer of the fluid is small

  15. Charge and magnetization inhomogeneities in diluted magnetic semiconductors

    E-Print Network [OSTI]

    Timm, Carsten

    2006-03-01T23:59:59.000Z

    It is predicted that III-V diluted magnetic semiconductors can exhibit stripelike modulations of magnetization and carrier concentration. This inhomogeneity results from the strong dependence of the magnetization on the carrier concentration. Within...

  16. Sideband Cooling Micromechanical Motion to the Quantum Ground State

    E-Print Network [OSTI]

    Teufel, J D; Li, Dale; Harlow, J H; Allman, M S; Cicak, K; Sirois, A J; Whittaker, J D; Lehnert, K W; Simmonds, R W

    2011-01-01T23:59:59.000Z

    The advent of laser cooling techniques revolutionized the study of many atomic-scale systems. This has fueled progress towards quantum computers by preparing trapped ions in their motional ground state, and generating new states of matter by achieving Bose-Einstein condensation of atomic vapors. Analogous cooling techniques provide a general and flexible method for preparing macroscopic objects in their motional ground state, bringing the powerful technology of micromechanics into the quantum regime. Cavity opto- or electro-mechanical systems achieve sideband cooling through the strong interaction between light and motion. However, entering the quantum regime, less than a single quantum of motion, has been elusive because sideband cooling has not sufficiently overwhelmed the coupling of mechanical systems to their hot environments. Here, we demonstrate sideband cooling of the motion of a micromechanical oscillator to the quantum ground state. Entering the quantum regime requires a large electromechanical inte...

  17. Ground-based transmission line conductor motion sensor

    SciTech Connect (OSTI)

    Jacobs, M.L.; Milano, U.

    1988-08-22T23:59:59.000Z

    A ground-based-conductor motion-sensing apparatus is provided for remotely sensing movement of electric-power transmission lines, particularly as would occur during the wind-induced condition known as galloping. The apparatus is comprised of a motion sensor and signal-generating means which are placed underneath a transmission line and will sense changes in the electric field around the line due to excessive line motion. The detector then signals a remote station when a conditioning of galloping is sensed. The apparatus of the present invention is advantageous over the line-mounted sensors of the prior art in that it is easier and less hazardous to install. The system can also be modified so that a signal will only be given when particular conditions, such as specific temperature range, large-amplitude line motion, or excessive duration of the line motion, are occurring.

  18. Interaction between magnetic vortex cores in a pair of nonidentical nanodisks

    SciTech Connect (OSTI)

    Sinnecker, J. P.; Vigo-Cotrina, H.; Garcia, F.; Novais, E. R. P.; Guimarães, A. P., E-mail: apguima@cbpf.br [Centro Brasileiro de Pesquisas Físicas, 22290-180, Rio de Janeiro, Rio de Janeiro (Brazil)

    2014-05-28T23:59:59.000Z

    The coupling of two nonidentical magnetic nanodisks, i.e., with different vortex gyrotropic frequencies, is studied. From the analytical approach, the interactions between the nanodisks along x and y directions (the coupling integrals) were obtained as a function of distance. From the numerical solution of Thiele's equation, we derived the eigenfrequencies of the vortex cores as a function of distance. The motion of the two vortex cores and, consequently, the time dependence of the total magnetization M(t) were derived both using Thiele's equation and by micromagnetic simulation. From M(t), a recently developed method, the magnetic vortex echoes, analogous to the Nuclear Magnetic Resonance spin echoes, was used to compute the distance dependence of the magnetic coupling strength. The results of the two approaches differ by approximately 10%; using one single term, a dependence with distance found is broadly in agreement with studies employing other techniques.

  19. Journal of Magnetism and Magnetic Materials 252 (2002) 159161 Magnetically induced alignment of FNS

    E-Print Network [OSTI]

    Reznikov, Yuri

    Journal of Magnetism and Magnetic Materials 252 (2002) 159­161 Magnetically induced alignment the observation of magnetically controlled anchoring of ferro-nematic suspensions. We found that application of a weak magnetic field to a cell with the ferro-suspension induces an easy orientation axis with weak

  20. High Temperature, Permanent Magnet Biased Magnetic Bearings

    E-Print Network [OSTI]

    Gandhi, Varun R.

    2010-07-14T23:59:59.000Z

    , then the molding process was carried out to form the potting cement on the each stator. After this the stators are baked in the oven and once ready the magnets and back-irons are put onto the stator. Shown below in Figure 3-11 is an assembly tool designed... rings. The bearing and its support rings were then carried onto the test rig and mounted at one end of the table. Throughout the assembly process a lot of care had to be taken so as to avoid damaging of the permanent magnets, stator and its coils...

  1. Magnetic Gas Sensing Using a Dilute Magnetic Semiconductor. ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Abstract: The authors report on a magnetic gas sensing methodology to detect hydrogen using the ferromagnetic properties of a nanoscale dilute magnetic semiconductor...

  2. Superconducting Magnet Division

    E-Print Network [OSTI]

    Ohta, Shigemi

    Superconducting Magnet Division MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R.6 A gun collectors gun Combined Horizontal and Vertical Corrector Design Both types of dipole correctors. Gupta, M. Anerella, W. Fischer, G. Ganetis, X. Gu, A. Ghosh, A. Jain, P. Kovach, A. Marone, S. Plate, A

  3. Passive magnetic bearing configurations

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2011-01-25T23:59:59.000Z

    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  4. Active Magnetic Regenerator Experimental Optimization

    E-Print Network [OSTI]

    Victoria, University of

    the potential to create more efficient and compact refrigeration devices is an Active Magnetic Regenerative temperature refrigerators, as well as efficient gas liquefaction plants (AMRLs). Active Magnetic Regenerator Refrigeration exploits the magnetocaloric effect displayed by magnetic materials whereby a reversible

  5. Automatically Generating Eye Motion in Virtual Agents Eye Motion has a fundamental role in verbal and non-verbal

    E-Print Network [OSTI]

    Animation's applications, such as virtual humans in general and game/movies characters. This paper presents tagging 1. INTRODUCTION Virtual humans have been widely used in many applica- tions. One is concernedAutomatically Generating Eye Motion in Virtual Agents ABSTRACT Eye Motion has a fundamental role

  6. M. Flierl: Motion-Compensated Orthogonal Transforms for Multiview Video Coding, EURASIP EUSIPCO, Poznan, Poland, Sep. 2007. 1 MOTION-COMPENSATED ORTHOGONAL TRANSFORMS

    E-Print Network [OSTI]

    Flierl, Markus

    of motion information. This is in contrast to the well known motion-compensated lifted wavelets where in time and view direction are cascaded. Motion-compensated lifted wavelets suffer from their motion. Well known examples are free viewpoint video [1] and free viewpoint television (FTV) [2]. For all

  7. M. Flierl: Adaptive Spatial Wavelets for Motion-Compensated Orthogonal Video Transforms, IEEE ICIP, Cairo, Egypt, Nov. 2009. 1 ADAPTIVE SPATIAL WAVELETS FOR MOTION-COMPENSATED

    E-Print Network [OSTI]

    Flierl, Markus

    , Cairo, Egypt, Nov. 2009. 1 ADAPTIVE SPATIAL WAVELETS FOR MOTION-COMPENSATED ORTHOGONAL VIDEO TRANSFORMS

  8. Motion of fluxons in distributed two-dimensional Josephson tunnel junctions

    SciTech Connect (OSTI)

    Nevirkovets, I.P.; Rudenko, E.M.

    1984-01-01T23:59:59.000Z

    A strong asymmetry is observed in the current--voltage characteristics of distributed two-dimensional Sn--I--Sn, Sn--I--Pb tunnel junctions with dimensions L>>lambda/sub J/ when an external magnetic field is applied in the plane of the junction perpendicular to the L dimension for different orientations of the field. A resistive section in the form of an almost vertical step appears in the IVC in one orientation of the field and is absent in the opposite orientation. It is shown that the appearance of the steps is related to the conditions of motion of Josephson vortices in tunnel junctions under the action of the Lorentz force in the presence of a current domain at the edge of the distributed junction.

  9. Microscopic Motion of Liquid Metal Plasma Facing Components In A Diverted Plasma

    SciTech Connect (OSTI)

    Jaworski, M A; Morley, N B; Abrams, T; Kaita, R; Kallman, J; Kugel, H; Majeski, R

    2010-09-22T23:59:59.000Z

    Liquid metal plasma facing components (PFCs) have been identified as an alternative material for fusion plasma experiments. The use of a liquid conductor where significant magnetic fields are present is considered risky, with the possibility of macroscopic fluid motion and possible ejection into the plasma core. Analysis is carried out on thermoelectric magnetohydrodynamic (TEMHD) forces caused by temperature gradients in the liquid-container system itself in addition to scrape-off-layer currents interacting with the PFC from a diverted plasma. Capillary effects at the liquid-container interface will be examined which govern droplet ejection criteria. Stability of the interface is determined using linear stability methods. In addition to application to liquidmetal PFCs, thin film liquidmetal effects have application to current and future devices where off-normal events may liquefy portions of the first wall and other plasma facing components.

  10. Review and comparison of magnet designs for magnetic refrigeration

    E-Print Network [OSTI]

    Bjørk, R; Smith, A; Pryds, N

    2014-01-01T23:59:59.000Z

    One of the key issues in magnetic refrigeration is generating the magnetic field that the magnetocaloric material must be subjected to. The magnet constitutes a major part of the expense of a complete magnetic refrigeration system and a large effort should therefore be invested in improving the magnet design. A detailed analysis of the efficiency of different published permanent magnet designs used in magnetic refrigeration applications is presented in this paper. Each design is analyzed based on the generated magnetic flux density, the volume of the region where this flux is generated and the amount of magnet material used. This is done by characterizing each design by a figure of merit magnet design efficiency parameter, $\\Lambda_\\mathrm{cool}$. The designs are then compared and the best design found. Finally recommendations for designing the ideal magnet design are presented based on the analysis of the reviewed designs.

  11. Condensed Matter and Magnet Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and HC) Suite of nondestructive pulsed magnets up to 100 tesla Thermoacoustics and fluid dynamics Transport, magnetism, and thermodynamic characterization at extreme conditions of...

  12. QUENCHES IN LARGE SUPERCONDUCTING MAGNETS

    E-Print Network [OSTI]

    Eberhard, P.H.

    2010-01-01T23:59:59.000Z

    QUENCHES IN LARGE SUPERCONDUCTING MAGNETS. P. H. Eberhard,Study of an Unprotected Superconducting Coil Going Normal,"Method for Testing Superconducting Magnets," LBL Physics

  13. Large Magnetization at Carbon Surfaces

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Large Magnetization at Carbon Surfaces Large Magnetization at Carbon Surfaces Print Wednesday, 31 August 2011 00:00 From organic matter to pencil lead, carbon is a versatile...

  14. Journal of Magnetism and Magnetic Materials ] (

    E-Print Network [OSTI]

    Schumann, Rolf

    width of internal field fluctuations. For the ``normal'' TR of the metallic magnets SmCo5; Sm2Co17 of the parameters for SmCo5 and barium ferrite. Susceptibility measurements with small alternating fields, carried out at different points of the TR curve, as well as repeating TR-experiments at SmCo5 demonstrate

  15. Variations of the solar granulation motions with height using the GOLF/SoHO experiment

    E-Print Network [OSTI]

    S. Lefebvre; R. A. Garcia; S. J. Jimenez-Reyes; S. Turck-Chieze; S. Mathur

    2008-08-04T23:59:59.000Z

    Below 1 mHz, the power spectrum of helioseismic velocity measurements is dominated by the spectrum of convective motions (granulation and supergranulation) making it difficult to detect the low-order acoustic modes and the gravity modes. We want to better understand the behavior of solar granulation as a function of the observing height in the solar atmosphere and with magnetic activity during solar cycle 23. We analyze the Power Spectral Density (PSD) of eleven years of GOLF/SOHO velocity-time series using a Harvey-type model to characterize the properties of the convective motions in the solar oscillation power spectrum. We study then the evolution of the granulation with the altitude in the solar atmosphere and with the solar activity. First, we show that the traditional use of a lorentzian profile to fit the envelope of the p modes is not well suitable for GOLF data. Indeed, to properly model the solar spectrum, we need a second lorentzian profile. Second, we show that the granulation clearly evolves with the height in the photosphere but does not present any significant variation with the activity cycle.

  16. arXiv:cond-mat/0307631v125Jul2003 typeset using JPSJ.sty

    E-Print Network [OSTI]

    magnetization. If the magnetic field is reversed, then the anti-domain of the magnetization appears at the edge conductivity of nanowires in the presence of magnetic domain walls by the method of wave packet propagation. We simulation. We propose a procedure, based on the Landauer formula, to reduce this dependence. Direct

  17. Barriers in the transition to global chaos in collisionless magnetic reconnection. II. Field line spectroscopy

    SciTech Connect (OSTI)

    Borgogno, D. [Dipartimento di Energetica, Politecnico di Torino, Torino (Italy); Grasso, D. [CNR Consiglio Nazionale delle Ricerche, Istituto dei Sistemi Complessi, Dipartimento di Energetica, Politecnico di Torino, Torino (Italy); Pegoraro, F. [Department of Physics, Pisa University, Pisa CNISM (Italy); Schep, T. J. [Department of Physics, Eindhoven University of Technology, Eindhoven (Netherlands)

    2011-10-15T23:59:59.000Z

    The transitional phase from local to global chaos in the magnetic field of a reconnecting current layer is investigated. The identification of the ridges in the field of the finite time Lyapunov exponent as barriers to the field line motion is carried out adopting the technique of field line spectroscopy to analyze the radial position of a field line while it winds its way through partial stochastic layers and to compare the frequencies of the field line motion with the corresponding frequencies of the distinguished hyperbolic field lines that are the nonlinear generalizations of linear X-lines.

  18. Permanent magnet energy conversion machine with magnet mounting arrangement

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN); Adams, Donald J. (Knoxville, TN)

    1999-01-01T23:59:59.000Z

    A hybrid permanent magnet dc motor includes three sets of permanent magnets supported by the rotor and three sets of corresponding stators fastened to the surrounding frame. One set of magnets operates across a radial gap with a surrounding radial gap stator, and the other two sets of magnets operate off the respective ends of the rotor across respective axial gaps.

  19. Magnetic Resonance Imaging System Based on Earth's Magnetic Field

    E-Print Network [OSTI]

    Stepi?nik, Janez

    Magnetic Resonance Imaging System Based on Earth's Magnetic Field Ales Mohoric,1,* Gorazd Planinsic magnetic field can be partly compensated by the receiving coil design and shielding of electromagnetic pick and must be monitored accurately.[8­ 10] The importance of NMR in a non-uniform magnetic field

  20. Monitoring internal organ motion with continuous wave radar in CT

    SciTech Connect (OSTI)

    Pfanner, Florian [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany)] [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany); Maier, Joscha [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Allmendinger, Thomas; Flohr, Thomas [Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany)] [Siemens AG, Healthcare Sector, Siemensstr. 1, 91301 Forchheim (Germany); Kachelrieß, Marc [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Institute of Medical Physics, University of Erlangen–Nürnberg, 91052 Erlangen, Germany and Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

    2013-09-15T23:59:59.000Z

    Purpose: To avoid motion artifacts in medical imaging or to minimize the exposure of healthy tissues in radiation therapy, medical devices are often synchronized with the patient's respiratory motion. Today's respiratory motion monitors require additional effort to prepare the patients, e.g., mounting a motion belt or placing an optical reflector on the patient's breast. Furthermore, they are not able to measure internal organ motion without implanting markers. An interesting alternative to assess the patient's organ motion is continuous wave radar. The aim of this work is to design, implement, and evaluate such a radar system focusing on application in CT.Methods: The authors designed a radar system operating in the 860 MHz band to monitor the patient motion. In the intended application of the radar system, the antennas are located close to the patient's body inside the table of a CT system. One receive and four transmitting antennas are used to avoid the requirement of exact patient positioning. The radar waves propagate into the patient's body and are reflected at tissue boundaries, for example at the borderline between muscle and adipose tissue, or at the boundaries of organs. At present, the authors focus on the detection of respiratory motion. The radar system consists of the hardware mentioned above as well as of dedicated signal processing software to extract the desired information from the radar signal. The system was evaluated using simulations and measurements. To simulate the radar system, a simulation model based on radar and wave field equations was designed and 4D respiratory-gated CT data sets were used as input. The simulated radar signals and the measured data were processed in the same way. The radar system hardware and the signal processing algorithms were tested with data from ten volunteers. As a reference, the respiratory motion signal was recorded using a breast belt simultaneously with the radar measurements.Results: Concerning the measurements of the test persons, there is a very good correlation (?= 0.917) between the respiratory motion phases received by the radar system and the external motion monitor. Our concept of using an array of transmitting antennas turned out to be widely insensitive to the positioning of the test persons. A time shift between the respiratory motion curves recorded with the radar system and the motion curves from the external respiratory monitor was observed which indicates a slight difference between internal organ motion and motion detected by the external respiratory monitor. The simulations were in good accordance with the measurements.Conclusions: A continuous wave radar operating in the near field of the antennas can be used to determine the respiratory motion of humans accurately. In contrast to trigger systems used today, the radar system is able to measure motion inside the body. If such a monitor was routinely available in clinical CT, it would be possible optimizing the scan start with respect to the respiratory state of the patient. Breathing commands would potentially widely be avoided, and as far as uncooperative patients or children are concerned, less sedation might be necessary. Further applications of the radar system could be in radiation therapy or interventional imaging for instance.

  1. Moment free toroidal magnet

    DOE Patents [OSTI]

    Bonanos, Peter (East Brunswick, NJ)

    1983-01-01T23:59:59.000Z

    A toroidal magnet for confining a high magnetic field for use in fusion reactor research and nuclear particle detection. The magnet includes a series of conductor elements arranged about and fixed at its small major radius portion to the outer surface of a central cylindrical support each conductor element having a geometry such as to maintain the conductor elements in pure tension when a high current flows therein, and a support assembly which redistributes all or part of the tension which would otherwise arise in the small major radius portion of each coil element to the large major radius portion thereof.

  2. Spontaneous motion in hierarchically assembled active matter

    E-Print Network [OSTI]

    Tim Sanchez; Daniel T. N. Chen; Stephen J. DeCamp; Michael Heymann; Zvonimir Dogic

    2013-01-07T23:59:59.000Z

    With exquisite precision and reproducibility, cells orchestrate the cooperative action of thousands of nanometer-sized molecular motors to carry out mechanical tasks at much larger length scales, such as cell motility, division and replication. Besides their biological importance, such inherently non-equilibrium processes are an inspiration for developing biomimetic active materials from microscopic components that consume energy to generate continuous motion. Being actively driven, these materials are not constrained by the laws of equilibrium statistical mechanics and can thus exhibit highly sought-after properties such as autonomous motility, internally generated flows and self-organized beating. Starting from extensile microtubule bundles, we hierarchically assemble active analogs of conventional polymer gels, liquid crystals and emulsions. At high enough concentration, microtubules form a percolating active network characterized by internally driven chaotic flows, hydrodynamic instabilities, enhanced transport and fluid mixing. When confined to emulsion droplets, 3D networks spontaneously adsorb onto the droplet surfaces to produce highly active 2D nematic liquid crystals whose streaming flows are controlled by internally generated fractures and self-healing, as well as unbinding and annihilation of oppositely charged disclination defects. The resulting active emulsions exhibit unexpected properties, such as autonomous motility, which are not observed in their passive analogues. Taken together, these observations exemplify how assemblages of animate microscopic objects exhibit collective biomimetic properties that are starkly different from those found in materials assembled from inanimate building blocks, challenging us to develop a theoretical framework that would allow for a systematic engineering of their far-from-equilibrium material properties.

  3. The universal criterion for switching a magnetic vortex core in soft magnetic nanodots

    SciTech Connect (OSTI)

    Lee, K.-S.; Kim, S.-K.; Yu, Y.-S.; Choi, Y.-S.; Guslienko, K. Y.; Jung, H.; Fischer, P.

    2008-10-01T23:59:59.000Z

    The universal criterion for ultrafast vortex core switching between core-up and -down vortex bi-states in soft magnetic nanodots was empirically investigated by micromagnetic simulations and combined with an analytical approach. Vortex-core switching occurs whenever the velocity of vortex core motion reaches a critical value, which is {nu}{sub c} = 330 {+-} 37 m/s for Permalloy, as estimated from numerical simulations. This critical velocity was found to be {nu}{sub c} = {eta}{sub c}{gamma} {radical}A{sub ex} with A{sub ex} the exchange stiffness, {gamma} the gyromagnetic ratio, and an estimated proportional constant {eta}{sub c} = 1.66 {+-} 0.18. This criterion does neither depend on driving force parameters nor on the dimension or geometry of the magnetic specimen. The phase diagrams for the vortex core switching criterion and its switching time with respect to both the strength and angular frequency of circular rotating magnetic fields were derived, which offer practical guidance for implementing vortex core switching into future solid state information storage devices.

  4. LONG-LIVED MAGNETIC-TENSION-DRIVEN MODES IN A MOLECULAR CLOUD

    SciTech Connect (OSTI)

    Basu, Shantanu; Dapp, Wolf B., E-mail: basu@uwo.c, E-mail: wdapp@uwo.c [Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7 (Canada)

    2010-06-10T23:59:59.000Z

    We calculate and analyze the longevity of magnetohydrodynamic (MHD) wave modes that occur in the plane of a magnetic thin sheet. Initial turbulent conditions applied to a magnetically subcritical cloud are shown to lead to relatively rapid energy decay if ambipolar diffusion is introduced at a level corresponding to partial ionization primarily by cosmic rays. However, in the flux-freezing limit, as may be applicable to photoionized molecular cloud envelopes, the turbulence persists at 'nonlinear' levels in comparison with the isothermal sound speed c {sub s}, with one-dimensional rms material motions in the range of {approx} 2 c {sub s}-5 c {sub s} for cloud sizes in the range of {approx} 2 pc-16 pc. These fluctuations persist indefinitely, maintaining a significant portion of the initial turbulent kinetic energy. We find the analytic explanation for these persistent fluctuations. They are magnetic-tension-driven modes associated with the interaction of the sheet with the external magnetic field. The phase speed of such modes is quite large, allowing residual motions to persist without dissipation in the flux-freezing limit, even as they are nonlinear with respect to the sound speed. We speculate that long-lived large-scale MHD modes such as these may provide the key to understanding observed supersonic motions in molecular clouds.

  5. Theory of hair bundle motion: new insights from the simplest model of hair bundle

    E-Print Network [OSTI]

    Ji, Seung Keun

    2013-01-01T23:59:59.000Z

    2 Single Hair bundle motion and a simpleas a model of a single hair bundle motion . . . . . . . . .of mechan- otransduction in hair cells. ” Annu Rev Neurosci,

  6. 1358 IEEE TRANSACTIONS ON MAGNETICS, VOL. 40, NO. 2, MARCH 2004 Eddy-Current Effects in Circuit Breakers During Arc

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1358 IEEE TRANSACTIONS ON MAGNETICS, VOL. 40, NO. 2, MARCH 2004 Eddy-Current Effects in Circuit Abstract--This paper deals with the modeling of eddy currents generated by arc motion during opening phases in determining eddy currents in splitter plates, the second one is devoted to the calculation of eddy currents

  7. Modular tokamak magnetic system

    DOE Patents [OSTI]

    Yang, Tien-Fang (Wayland, MA)

    1988-01-01T23:59:59.000Z

    A modular tokamak system comprised of a plurality of interlocking moldules. Each module is comprised of a vacuum vessel section, a toroidal field coil, moldular saddle coils which generate a poloidal magnetic field and ohmic heating coils.

  8. Geometrically frustrated quantum magnets

    E-Print Network [OSTI]

    Nikolić , Predrag, 1974-

    2004-01-01T23:59:59.000Z

    (cont.) more general lessons on frustrated quantum magnetism. At the end, we demonstrate some new mathematical tools on two other frustrated two-dimensional systems, and summarize our conclusions, with an outlook to remaining ...

  9. Ultrafast Magnetic Light

    E-Print Network [OSTI]

    Makarov, Sergey V; Krasnok, Alexander E; Belov, Pavel A

    2015-01-01T23:59:59.000Z

    We propose a novel concept for efficient dynamic tuning of optical properties of a high refractive index subwavelength nanoparticle with a magnetic Mie-type resonance by means of femtosecond laser radiation. This concept is based on ultrafast generation of electron-hole plasma within such nanoparticle, drastically changing its transient dielectric permittivity. This allows to manipulate by both electric and magnetic nanoparticle responses, resulting in dramatic changes of its extinction cross section and scattering diagram. Specifically, we demonstrate the effect of ultrafast switching-on a Huygens source in the vicinity of the magnetic dipole resonance. This approach enables to design ultrafast and compact optical switchers and modulators based on the "ultrafast magnetic light" concept.

  10. Magnetic gripper device

    DOE Patents [OSTI]

    Meyer, Ross E. (Los Alamos, NM)

    1993-01-01T23:59:59.000Z

    A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.

  11. Magnetic gripper device

    DOE Patents [OSTI]

    Meyer, R.E.

    1993-03-09T23:59:59.000Z

    A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.

  12. Passive electromagnetic damping device for motion control of building structures

    E-Print Network [OSTI]

    Palomera-Arias, Rogelio, 1972-

    2005-01-01T23:59:59.000Z

    The research presented in this thesis develops a new device for the passive control of motion in building structures: an electromagnetic damper. The electromagnetic damper is a self-excited device that provides a reaction ...

  13. Bulgarian Verbs of Motion: Slavic Verbs in a Balkan Context

    E-Print Network [OSTI]

    Lindsey, Traci Speed

    2011-01-01T23:59:59.000Z

    motion events in Serbo-Croatian. In Victoria Hasko & ReneeRussian and Bosnian-Croatian-Serbian (BCS). The theoreticalRussian and Bosnian-Croatian-Serbian (BCS). Theoretical

  14. Motion to intervene and comments of the energy services group...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    intervene and comments of the energy services group of Hydro-Quebec and H.Q. Energy Services (U.S.) Inc, on FE 99-1 Motion to intervene and comments of the energy services group of...

  15. Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles

    E-Print Network [OSTI]

    Smith, Ryan N.

    Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles Monique Chyba, such as time, energy, payload or some combination of these. Indeed, the major issue is that due to the vehicles

  16. for Computer Animation and Robotics Visual Analysis of Biomimetic Motion

    E-Print Network [OSTI]

    Hale, Joshua G.

    Joshua G. Hale & Frank E. Pollick Motion production algorithms are based on human motor production numerically integrated cost functions and solved using the Simplex method. A computationally efficient optimal

  17. The early American motion picture industry: promoting American cultural hegemony 

    E-Print Network [OSTI]

    Wier, Theresa Joanne

    1994-01-01T23:59:59.000Z

    of the United States. Analysis of the impact of the motion picture in the United States and Europe during this period provides insight into the role of film industry....

  18. Sound-induced micromechanical motions in an isolated cochlea preparation

    E-Print Network [OSTI]

    Page, Scott Lawrence

    2006-01-01T23:59:59.000Z

    The mechanical processes at work within the organ of Corti can be greatly elucidated by measuring both radial motions and traveling-wave behavior of structures within this organ in response to sound stimuli. To enable such ...

  19. ahumada motion detector: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    We show data from a new type of detector that can be used to determine the neutron flux, the energy distribution, and the direction of motion neutron for both fast and thermal...

  20. Sandia National Laboratories: governing WEC equations of motion...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    governing WEC equations of motion in six degrees of freedom Sandia, NREL Release Wave Energy Converter Modeling and Simulation Code: WEC-Sim On July 29, 2014, in Computational...

  1. John Papanikolas: Visualizing Charge Carrier Motion in Nanowires...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    John Papanikolas: Visualizing Charge Carrier Motion in Nanowires Using Femtosecond Pump-Probe Microscopy Apr 17, 2014 | 4:00 PM - 5:00 PM John Papanikolas Professor of Chemistry &...

  2. Wavelet Packets of fractional Brownian motion: Asymptotic Analysis and Spectrum

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Wavelet Packets of fractional Brownian motion: Asymptotic Analysis and Spectrum Estimation properties of the autocorrelation functions of the wavelet packet coefficients of a fractional Brownian process. The analysis concerns some families of wavelet paraunitary filters that converge almost

  3. Perceptual motion standstill in rapidly moving chromatic displays

    E-Print Network [OSTI]

    Sperling, George

    a narrow range of luminance contrasts and green red saturation ratios, moving stimuli were perceived, e.g., as in the slow movement of the moon across the sky, no motion or a stationary object

  4. Wave-induced motion of ramp-interconnected craft

    E-Print Network [OSTI]

    Oonk, Stephen Holt

    2008-01-01T23:59:59.000Z

    OF CALIFORNIA, SAN DIEGO Wave-Induced Motion of Ramp-5 2.1 Mathematical Description of the Wave49 4.2 Case 1: Waves are Parallel to Ship-Ramp-Ship Axis (

  5. Cataclysmic variables in the SUPERBLINK proper motion survey

    SciTech Connect (OSTI)

    Skinner, Julie N.; Thorstensen, John R. [Department of Physics and Astronomy, 6127 Wilder Laboratory, Dartmouth College, Hanover, NH 03755-3528 (United States); Lépine, Sébastien, E-mail: jns@dartmouth.edu [Department of Physics and Astronomy, Georgia State University, 25 Park Place NE, Atlanta, GA 30303 (United States)

    2014-12-01T23:59:59.000Z

    We have discovered a new high proper motion cataclysmic variable (CV) in the SUPERBLINK proper motion survey, which is sensitive to stars with proper motions greater than 40 mas yr{sup ?1}. This CV was selected for follow-up observations as part of a larger search for CVs selected based on proper motions and their near-UV?V and V?K{sub s} colors. We present spectroscopic observations from the 2.4 m Hiltner Telescope at MDM Observatory. The new CV's orbital period is near 96 minutes, its spectrum shows the double-peaked Balmer emission lines characteristic of quiescent dwarf novae, and its V magnitude is near 18.2. Additionally, we present a full list of known CVs in the SUPERBLINK catalog.

  6. Hierarchical Task and Motion Planning in the Now

    E-Print Network [OSTI]

    Kaelbling, Leslie Pack

    2010-05-07T23:59:59.000Z

    In this paper we outline an approach to the integration of task planning and motion planning that has the following key properties: It is aggressively hierarchical. It makes choices and commits to them in a top-down fashion ...

  7. Integrated Robot Task and Motion Planning in the Now

    E-Print Network [OSTI]

    Kaelbling, Leslie Pack

    2012-06-29T23:59:59.000Z

    This paper provides an approach to integrating geometric motion planning with logical task planning for long-horizon tasks in domains with many objects. We propose a tight integration between the logical and geometric ...

  8. Information-Theoretic Motion Planning for Constrained Sensor Networks

    E-Print Network [OSTI]

    Levine, Daniel

    2012-07-20T23:59:59.000Z

    This paper considers the problem of online informative motion planning for a network of heterogeneous sensing agents, each subject to dynamic constraints, environmental constraints, and sensor limitations. Prior work has ...

  9. Motion to Intervene and Comments of Public Utility District No...

    Broader source: Energy.gov (indexed) [DOE]

    A motion to intervene and comments from Public Utility District No. 1 (Pend Oreille County, Washington) on PP 99-1 Notice of Intent to Amend Presidential Permit, where DOE proposes...

  10. Vibration suppression, stabilization, motion planning and tracking for flexible beams

    E-Print Network [OSTI]

    Siranosian, Antranik Antonio

    2009-01-01T23:59:59.000Z

    Target System . . . . 3.2.3 Flexible Beams . . . 3.3 MotionPlanning and Tracking for Flexible Beams A Dissertationand De?ection Angle for Flexible Beams,” ASME Journal of

  11. A Comparative Study of Estimation Models for Satellite Relative Motion 

    E-Print Network [OSTI]

    Desai, Uri

    2013-01-31T23:59:59.000Z

    The problem of relative spacecraft motion estimation is considered with application to various reference and relative orbits. Mean circular and elliptic orbits are analyzed, with relative orbits ranging in size from 1 km ...

  12. Magnetic susceptibility, magnetization, magnetic moment and characterization of Carancas meteorite

    E-Print Network [OSTI]

    Rosales, Domingo

    2015-01-01T23:59:59.000Z

    On September, 15th, 2007, in the community of Carancas (Puno, Peru) a stony meteorite formed a crater explosive type with a mean diameter of 13.5 m. some samples meteorite fragments were collected. The petrologic analysis performed corresponds to a meteorite ordinary chondrite H 4-5. In this paper we have analyzed the magnetic properties of a meteorite fragment with a proton magnetometer. Also in order to have a complete characterization of the Carancas meteorite and its crater, from several papers, articles and reports, we have made a compilation of the most important characteristics and properties of this meteorite.

  13. Permanent Magnet Ecr Plasma Source With Magnetic Field Optimization

    DOE Patents [OSTI]

    Doughty, Frank C. (Plano, TX); Spencer, John E. (Plano, TX)

    2000-12-19T23:59:59.000Z

    In a plasma-producing device, an optimized magnet field for electron cyclotron resonance plasma generation is provided by a shaped pole piece. The shaped pole piece adjusts spacing between the magnet and the resonance zone, creates a convex or concave resonance zone, and decreases stray fields between the resonance zone and the workpiece. For a cylindrical permanent magnet, the pole piece includes a disk adjacent the magnet together with an annular cylindrical sidewall structure axially aligned with the magnet and extending from the base around the permanent magnet. The pole piece directs magnetic field lines into the resonance zone, moving the resonance zone further from the face of the magnet. Additional permanent magnets or magnet arrays may be utilized to control field contours on a local scale. Rather than a permeable material, the sidewall structure may be composed of an annular cylindrical magnetic material having a polarity opposite that of the permanent magnet, creating convex regions in the resonance zone. An annular disk-shaped recurve section at the end of the sidewall structure forms magnetic mirrors keeping the plasma off the pole piece. A recurve section composed of magnetic material having a radial polarity forms convex regions and/or magnetic mirrors within the resonance zone.

  14. Magnetic coupling device

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC)

    2009-08-18T23:59:59.000Z

    A quick connect/disconnect coupling apparatus is provided in which a base member is engaged by a locking housing through a series of interengagement pins. The pins maintain the shaft in a locked position. Upon exposure to an appropriately positioned magnetic field, pins are removed a sufficient distance such that the shaft may be withdrawn from the locking housing. The ability to lock and unlock the connector assembly requires no additional tools or parts apart from a magnetic key.

  15. Magnetic fluorescent lamp

    DOE Patents [OSTI]

    Berman, S.M.; Richardson R.W.

    1983-12-29T23:59:59.000Z

    The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly is enhanced by providing means for establishing a magnetic field with lines of force along the path of electron flow through the bulb of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.

  16. Magnetic Fields in Quasar Cores II

    E-Print Network [OSTI]

    G. B. Taylor

    1999-11-22T23:59:59.000Z

    Multi-frequency polarimetry with the Very Long Baseline Array (VLBA) telescope has revealed absolute Faraday Rotation Measures (RMs) in excess of 1000 rad/m/m in the central regions of 7 out of 8 strong quasars studied (e.g., 3C 273, 3C 279, 3C 395). Beyond a projected distance of ~20 pc, however, the jets are found to have |RM| < 100 rad/m/m. Such sharp RM gradients cannot be produced by cluster or galactic-scale magnetic fields, but rather must be the result of magnetic fields organized over the central 1-100 pc. The RMs of the sources studied to date and the polarization properties of BL Lacs, quasars and galaxies are shown to be consistent so far with the predictions of unified schemes. The direct detection of high RMs in these quasar cores can explain the low fractional core polarizations usually observed in quasars at centimeter wavelengths as the result of irregularities in the Faraday screen on scales smaller than the telescope beam. Variability in the RM of the core is reported for 3C 279 between observations taken 1.5 years apart, indicating that the Faraday screen changes on that timescale, or that the projected superluminal motion of the inner jet components samples a new location in the screen with time. Either way, these changes in the Faraday screen may explain the dramatic variability in core polarization properties displayed by quasars.

  17. Scour around a circular pile due to oscillatory wave motion

    E-Print Network [OSTI]

    Wells, Donald Raymond

    1970-01-01T23:59:59.000Z

    ( COLEMAN ) 10 authors. In general the committee on sedimentation has found many inconsistencies in critical velocities necessary for incipient motion and have concluded that when studying incipient motion critical shear stresses should be the governing...- city of the paddle arm on the flywheel. The period is varied through a variable rheostat that controls the speed of the flywheel. The rocker arms can be varied so as to vary the wave from a deep water wave to a shallow water wave. Wave heights...

  18. Small mass asymptotic for the motion with vanishing friction

    E-Print Network [OSTI]

    Mark Freidlin; Wenqing Hu; Alexander Wentzell

    2012-08-30T23:59:59.000Z

    We consider the small mass asymptotic (Smoluchowski-Kramers approximation) for the Langevin equation with a variable friction coefficient. The friction coefficient is assumed to be vanishing within certain region. We introduce a regularization for this problem and study the limiting motion for the 1-dimensional case and a multidimensional model problem. The limiting motion is a Markov process on a projected space. We specify the generator and boundary condition of this limiting Markov process and prove the convergence.

  19. Roles of Dry Friction in Fluctuating Motion of Adiabatic Piston

    E-Print Network [OSTI]

    Tomohiko G. Sano; Hisao Hayakawa

    2014-03-08T23:59:59.000Z

    The motion of an adiabatic piston under dry friction is investigated to clarify the roles of dry friction in non-equilibrium steady states. We clarify that dry friction can reverse the direction of the piston motion and causes a discontinuity or a cusp-like singularity for velocity distribution functions of the piston. We also show that the heat fluctuation relation is modified under dry friction.

  20. Nonlinear behavior of reinforced concrete structures subjected to ground motion

    E-Print Network [OSTI]

    Abraham, Moises Alberto

    1991-01-01T23:59:59.000Z

    NONLINEAR BEHAVIOR OF REINFORCED CONCRETE STRUCTURES SUBJECTED TO GROUND MOTION A Thesis by MOISES ALBERTO ABRAHAM Submitted to the Office of Graduate Studies of Texas A 5 M U ni vers i ty in partial fulfillment of the requirement I...' or the degree of MASTER OF SCIENCE May 1991 Major Subject: Civil Engineering NONLINEAR BEHAVIOR OF REINFORCED CONCRETE STRUCTURES SUBJECTED TO GROUND MOTION A Thesis by MOISES ALBERTO ABRAHAM Approved as to style and content by: James . organ (Chair...