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Sample records for nonlinear current-carrying elementary

  1. Nonlinear Resonant Excitation of Fast Sausage Waves in Current-Carrying Coronal Loops

    Science.gov (United States)

    Mikhalyaev, B. B.; Bembitov, D. B.

    2014-11-01

    We consider a model of a coronal loop that is a cylindrical magnetic tube with two surface electric currents. Its principal sausage mode has no cut-off in the long-wavelength limit. For typical coronal conditions, the period of the mode is between one and a few minutes. The sausage mode of flaring loops could cause long-period pulsations observed in microwave and hard X-ray ranges. There are other examples of coronal oscillations: long-period pulsations of active-region quiet loops in the soft X-ray emission are observed. We assume that these can also be caused by sausage waves. The question arises of how the sausage waves are generated in quiet loops. We assume that they can be generated by torsional oscillations. This process can be described in the framework of the nonlinear three-wave interaction formalism. The periods of interacting torsional waves are similar to the periods of torsional oscillations observed in the solar atmosphere. The timescale of the sausage-wave excitation is not much longer than the periods of interacting waves, so that the sausage wave is excited before torsional waves are damped.

  2. The Pedersen current carried by electrons: a non-linear response of the ionosphere to magnetospheric forcing

    Directory of Open Access Journals (Sweden)

    S. C. Buchert

    2008-09-01

    Full Text Available Observations by the EISCAT Svalbard radar show that electron temperatures Te in the cusp electrojet reach up to about 4000 K. The heat is tapped and converted from plasma convection in the near Earth space by a Pedersen current that is carried by electrons due to the presence of irregularities and their demagnetising effect. The heat is transfered to the neutral gas by collisions. In order to enhance Te to such high temperatures the maximally possible dissipation at 50% demagnetisation must nearly be reached. The effective Pedersen conductances are found to be enhanced by up to 60% compared to classical values. Conductivities and conductances respond significantly to variations of the electric field strength E, and "Ohm's law" for the ionosphere becomes non-linear for large E.

  3. Magnetically Guiding Atoms with Current-Carrying Conductors

    Institute of Scientific and Technical Information of China (English)

    刘南春; 高伟建; 印建平

    2002-01-01

    We propose a novel magnetic guide for cold neutral atoms using some current-carrying conductors. The spatial distributions of the magnetic fields from a V-shaped or U-shaped current-carrying conductor are calculated, and the relationship between the resulting magnetic field and the parameters of the current-carrying conductors is analysed in detail. The result shows that these current-carrying conductors can be used to realize a single or a controllable double magnetic guide of cold atoms in the weak-field-seeking state, and to construct various atom-optical elements, and even to realize a single-mode atomic waveguiding under certain conditions.

  4. Measuring the Magnetic Force on a Current-Carrying Conductor.

    Science.gov (United States)

    Herreman, W.; Huysentruyt, R.

    1995-01-01

    Describes a fast and simple method for measuring the magnetic force acting on a current-carrying conductor using a digital balance. Discusses the influence of current intensity and wire length on the magnetic force on the conductor. (JRH)

  5. Formation of current filaments and magnetic field generation in a quantum current-carrying plasma

    Energy Technology Data Exchange (ETDEWEB)

    Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of); Taghadosi, M. R.; Majedi, S.; Khorashadizadeh, S. M. [Physics Department, University of Birjand, Birjand (Iran, Islamic Republic of)

    2013-09-15

    The nonlinear dynamics of filamentation instability and magnetic field in a current-carrying plasma is investigated in the presence of quantum effects using the quantum hydrodynamic model. A new nonlinear partial differential equation is obtained for the spatiotemporal evolution of the magnetic field in the diffusion regime. This equation is solved by applying the Adomian decomposition method, and then the profiles of magnetic field and electron density are plotted. It is shown that the saturation time of filamentation instability increases and, consequently, the instability growth rate and the magnetic field amplitude decrease in the presence of quantum effects.

  6. Elementary Superconductivity in Nonlinear Electrodynamics Coupled to Gravity

    CERN Document Server

    Dymnikova, Irina

    2015-01-01

    Source-free equations of nonlinear electrodynamics minimally coupled to gravity admit regular axially symmetric asymptotically Kerr-Newman solutions which describe charged rotating black holes and electromagnetic spinning solitons (lumps). Asymptotic analysis of solutions shows, for both black holes and solitons, the existence of de Sitter vacuum interior which has the properties of a perfect conductor and ideal diamagnetic and displays superconducting behaviour which can be responsible for practically unlimited life time of an object. Superconducting current flows on the equatorial ring replacing the Kerr ring singularity of the Kerr-Newman geometry. Interior de Sitter vacuum supplies the electron with the finite positive electromagnetic mass related the interior de Sitter vacuum of the electroweak scale and to breaking of space-time symmetry, which allows to explain the mass-square differences for neutrino and the appearance of the minimal length scale in the annihilation reaction $e^{+}e^{-}\\rightarrow\\gam...

  7. MAGNETIC-ELASTIC BUCKLING OF A THIN CURRENT CARRYING PLATE SIMPLY SUPPORTED AT THREE EDGES

    Institute of Scientific and Technical Information of China (English)

    WANG Zhiren; WANG Ping; BAI Xiangzhong

    2008-01-01

    The magnetic-elasticity buckling problem of a current plate under the action of a mechanical load in a magnetic field was studied by using the Mathieu function. According to the magnetic-elasticity non-linear kinetic equation, physical equations, geometric equations, the expression for Lorenz force and the electrical dynamic equation, the magnetic-elasticity dynamic buckling equation is derived. The equation is changed into a standard form of the Mathieu equation using Galerkin's method. Thus, the buckling problem can be solved with a Mathieu equation. The criterion equation of the buckling problem also has been obtained by discussing the eigenvalue relation of the coefficients λ and η in the Mathieu equation. As an example, a thin plate simply supported at three edges is solved here. Its magnetic-elasticity dynamic buckling equation and the relation curves of the instability state with variations in some parameters are also shown in this paper. The conclusions show that the electrical magnetic forces may be controlled by changing the parameters of the current or the magnetic field so that the aim of controlling the deformation, stress, strain and stability of the current carrying plate is achieved.

  8. The structure of fast sausage waves in current-carrying coronal loops

    Science.gov (United States)

    Bembitov, D. B.; Mikhalyaev, B. B.; Ruderman, M. S.

    2014-09-01

    We study fast sausage waves in a model coronal loop that consists of a cylindrical core with axial magnetic field and coaxial annulus with purely azimuthal magnetic field. The magnetic field is discontinuous at the tube and core boundaries, and there are surface currents with the opposite directions on these boundaries. The principal mode of fast sausage waves in which the magnetic pressure perturbation has no nodes in the radial direction can exist for arbitrary wavelength. The results for the fundamental radial mode of sausage waves are applied to the interpretation of observed periodic pulsations of microwave emission in flaring loops with periods of a few tens of seconds. Radial plasma motion has opposite directions at the tube and core boundaries. This leads to the periodic contraction and expansion of the annulus. We assume that the principal mode of fast sausage waves in the current-carrying coronal loops is able to produce a current sheet. However, the nonlinear analysis is needed to confirm this conjecture.

  9. Magnetic guide of cold atoms using a U-shaped current-carrying conductor

    Institute of Scientific and Technical Information of China (English)

    刘南春; 印建平

    2003-01-01

    We propose a new scheme to magnetically guide cold neutral atoms using a U-shaped current carrying conductor.The spatial magnetic field distribution from the U-shaped current-carrying conductor and the relationship between the magnetic field and parameters of the U-shaped conductor are analysed.Our study shows that U-shaped current-carrying conductor can be used to realize single-or double-channel magnetic guiding of cold atoms in weak-field-seeking states and to construct wrious atom-optical elements.By using Monte Carlo simulations,the dynamic process of the guided atomic-beam splitting in an atomic-beam splitter composed by the U-shaped current-carrying conductor is studied,and some results are presented.

  10. Surface barrier effect on magnetization of a current-carrying type-II superconductor

    Science.gov (United States)

    Genenko, Yu. A.; Freyhardt, H. C.

    2000-10-01

    Vortex penetration in and exit from ideal flux-filled current-carrying superconductors are studied in the frame of the modified Meissner state model accounting for the vortex interactions with the sample surface, transport current, external field and the other vortices inside the sample. The generalized Silsbee's rule is first formulated and the M- H diagram of ideal current-carrying superconductors in a parallel field is estimated which is irreversible due to the surface effect alone. In general, magnetic behaviour of superconductors is shown to be more reversible in the presence of a transport current.

  11. Charged Particle Dynamics in the Magnetic Field of a Long Straight Current-Carrying Wire

    Science.gov (United States)

    Prentice, A.; Fatuzzo, M.; Toepker, T.

    2015-01-01

    By describing the motion of a charged particle in the well-known nonuniform field of a current-carrying long straight wire, a variety of teaching/learning opportunities are described: 1) Brief review of a standard problem; 2) Vector analysis; 3) Dimensionless variables; 4) Coupled differential equations; 5) Numerical solutions.

  12. Magnetic focusing of cold atomic beam with a 2D array of current-carrying wires

    Institute of Scientific and Technical Information of China (English)

    Yang Liu; Min Yun; Jianping Yin

    2006-01-01

    @@ A new scheme to realize a two-dimensional (2D) array of magnetic micro-lenses for a cold atomic beam,formed by an array of square current-carrying wires,is proposed.We calculate the spatial distributions of the magnetic fields from the array of current-carrying wires and the magnetic focusing potential for cold rubidium atoms,and study the dynamic focusing processes of cold atoms passing through the magnetic micro-lens array and its focusing properties by using Monte-Carlo simulations and trajectory tracing method.The result shows that the proposed micro-lens array can be used to focus effectively a cold atomic beam,even to load ultracold atoms or a BEC sample into a 2D optical lattice formed by blue detuned hollow beams.

  13. Superior Current Carrying Capacity of Boron Nitride Encapsulated Carbon Nanotubes with Zero-Dimensional Contacts.

    Science.gov (United States)

    Huang, Jhao-Wun; Pan, Cheng; Tran, Son; Cheng, Bin; Watanabe, Kenji; Taniguchi, Takashi; Lau, Chun Ning; Bockrath, Marc

    2015-10-14

    We report fabrication and characterization of hexagonal boron nitride (hBN)-encapsulated carbon nanotube (CNT) field effect transistors, which are coupled to electrical leads via zero-dimensional contacts. Device quality is attested by the ohmic contacts and observation of Coulomb blockade with a single periodicity in small bandgap semiconducing nanotubes. Surprisingly, hBN-encapsulated CNT devices demonstrate significantly enhanced current carrying capacity; a single-walled CNT can sustain >180 μA current or, equivalently, a current density of ∼2 × 10(10) A/cm(2), which is a factor of 6-7 higher than devices supported on SiO2 substrates. Such dramatic enhancement of current carrying capacity arises from the high thermal conductivity of hBN and lower hBN-CNT interfacial thermal resistance and has implications for carbon electronic applications.

  14. Sausage instabilities on top of kinking lengthening current-carrying magnetic flux tubes

    Science.gov (United States)

    von der Linden, Jens; You, Setthivoine

    2017-05-01

    We theoretically explore the possibility of sausage instabilities developing on top of a kink instability in lengthening current-carrying magnetic flux tubes. Observations indicate that the dynamics of magnetic flux tubes in our cosmos and terrestrial experiments can involve topological changes faster than time scales predicted by resistive magnetohydrodynamics. Recent laboratory experiments suggest that hierarchies of instabilities, such as kink and Rayleigh-Taylor, could be responsible for initiating fast topological changes by locally accessing two-fluid and kinetic regimes. Sausage instabilities can also provide this coupling mechanism between disparate scales. Flux tube experiments can be classified by the flux tube's evolution in a configuration space described by a normalized inverse aspect-ratio k ¯ and current-to-magnetic flux ratio λ ¯ . A lengthening current-carrying magnetic flux tube traverses this k ¯ - λ ¯ space and crosses stability boundaries. We derive a single general criterion for the onset of the sausage and kink instabilities in idealized magnetic flux tubes with core and skin currents. The criterion indicates a dependence of the stability boundaries on current profiles and shows overlapping kink and sausage unstable regions in the k ¯ - λ ¯ space with two free parameters. Numerical investigation of the stability criterion reduces the number of free parameters to a single one that describes the current profile and confirms the overlapping sausage and kink unstable regions in k ¯ - λ ¯ space. A lengthening, ideal current-carrying magnetic flux tube can therefore become sausage unstable after it becomes kink unstable.

  15. Acceleration of magnetic dipoles by a sequence of current-carrying turns

    Science.gov (United States)

    Dolya, S. N.

    2014-11-01

    Magnetic dipoles are accelerated by a running gradient of the magnetic field that is produced by sequentially energizing current-carrying turns. Magnetic dipoles d sh = 60 mm in diameter and l tot = 1 m in length are gasdynamically preaccelerated to velocity V in = 1 km/s, with which they are injected into the main accelerator. The turnover of the dipoles in the field of an accelerating pulse is prevented and focusing of dipoles is provided by directing the dipoles into a titanium tube. The weight of the dipoles is m = 2 kg, and they acquire final velocity V fin = 5 km/s over acceleration length L acc = 300 m.

  16. Sharp burnout failure observed in high current-carrying double-walled carbon nanotube fibers

    Science.gov (United States)

    Song, Li; Toth, Geza; Wei, Jinquan; Liu, Zheng; Gao, Wei; Ci, Lijie; Vajtai, Robert; Endo, Morinobu; Ajayan, Pulickel M.

    2012-01-01

    We report on the current-carrying capability and the high-current-induced thermal burnout failure modes of 5-20 µm diameter double-walled carbon nanotube (DWNT) fibers made by an improved dry-spinning method. It is found that the electrical conductivity and maximum current-carrying capability for these DWNT fibers can reach up to 5.9 × 105 S m - 1 and over 1 × 105 A cm - 2 in air. In comparison, we observed that standard carbon fiber tended to be oxidized and burnt out into cheese-like morphology when the maximum current was reached, while DWNT fiber showed a much slower breakdown behavior due to the gradual burnout in individual nanotubes. The electron microscopy observations further confirmed that the failure process of DWNT fibers occurs at localized positions, and while the individual nanotubes burn they also get aligned due to local high temperature and electrostatic field. In addition a finite element model was constructed to gain better understanding of the failure behavior of DWNT fibers.

  17. Liquid nitrogen cooled integrated power electronics module with high current carrying capability and lower on resistance

    Science.gov (United States)

    Ye, Hua; Lee, Changwoo; Simon, Randy W.; Haldar, Pradeep; Hennessy, Michael J.; Mueller, Eduard K.

    2006-11-01

    This letter presents the development of high-performance integrated cryogenic power modules, where both driver components and power metal-oxide semiconductor field-effect transistors are integrated in a single package, to be used in a 50kW prototype cryogenic inverter operating at liquid nitrogen temperature. The authors have demonstrated a compact high-voltage, cryogenic integrated power module that exhibited more than 14 times improvement in on-resistance and continuous current carrying capability exceeding 40A. The modules are designed to operate at liquid nitrogen temperature with extreme thermal cycling. The power electronic modules are necessary components that provide control and switching for second generation, yttrium barium copper oxide-based high temperature superconductor devices including cables, motors, and generators.

  18. Phonon induced optical gain in a current carrying two-level quantum dot

    Energy Technology Data Exchange (ETDEWEB)

    Eskandari-asl, Amir, E-mail: amir.eskandari.asl@gmail.com [Department of Physics, Shahid Beheshti University, G.C. Evin, Tehran 1983963113 (Iran, Islamic Republic of); School of Nano Science, Institute for Research in Fundamental Sciences (IPM), P.O. Box: 19395-5531, Tehran, Iran (Iran, Islamic Republic of)

    2017-05-15

    In this work we consider a current carrying two level quantum dot (QD) that is coupled to a single mode phonon bath. Using self-consistent Hartree-Fock approximation, we obtain the I-V curve of QD. By considering the linear response of our system to an incoming classical light, we see that depending on the parametric regime, the system could have weak or strong light absorption or may even show lasing. This lasing occurs at high enough bias voltages and is explained by a population inversion considering side bands, while the total electron population in the higher level is less than the lower one. The frequency at which we have the most significant lasing depends on the level spacing and phonon frequency and not on the electron-phonon coupling strength.

  19. Suppression of vertical instability in elongated current-carrying plasmas by applying stellarator rotational transform

    Energy Technology Data Exchange (ETDEWEB)

    ArchMiller, M. C.; Cianciosa, M. R.; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Hebert, J. D.; Herfindal, J. L.; Knowlton, S. F.; Ma, X.; Maurer, D. A.; Pandya, M. D.; Traverso, P. [Physics Department, Auburn University, Auburn, Alabama 36849 (United States)

    2014-05-15

    The passive stability of vertically elongated current-carrying toroidal plasmas has been investigated in the Compact Toroidal Hybrid, a stellarator/tokamak hybrid device. In this experiment, the fractional transform f, defined as the ratio of the imposed external rotational transform from stellarator coils to the total rotational transform, was varied from 0.04 to 0.50, and the elongation κ was varied from 1.4 to 2.2. Plasmas that were vertically unstable were evidenced by motion of the plasma in the vertical direction. Vertical drifts are measured with a set of poloidal field pickup coils. A three chord horizontally viewing interferometer and a soft X-ray diode array confirmed the drifts. Plasmas with low fractional transform and high elongation are the most susceptible to vertical instability, consistent with analytic predictions that the vertical mode in elongated plasmas can be stabilized by the poloidal field of a relatively weak stellarator equilibrium.

  20. Sausage Instabilities on top of Kinking Lengthening Current-Carrying Magnetic Flux Tubes

    Science.gov (United States)

    von der Linden, Jens; You, Setthivoine

    2015-11-01

    Observations indicate that the dynamics of magnetic flux tubes in our cosmos and terrestrial experiments involve fast topological change beyond MHD reconnection. Recent experiments suggest that hierarchies of instabilities coupling disparate plasma scales could be responsible for this fast topological change by accessing two-fluid and kinetic scales. This study will explore the possibility of sausage instabilities developing on top of a kink instability in lengthening current-carrying magnetic flux tubes. Current driven flux tubes evolve over a wide range of aspect ratios k and current to magnetic flux ratios λ . An analytical stability criterion and numerical investigations, based on applying Newcomb's variational approach to idealized magnetic flux tubes with core and skin currents, indicate a dependence of the stability boundaries on current profiles and overlapping kink and sausage unstable regions in the k - λ trajectory of the flux tubes. A triple electrode planar plasma gun (Mochi.LabJet) is designed to generate flux tubes with discrete core and skin currents. Measurements from a fast-framing camera and a high resolution magnetic probe are being assembled into stability maps of the k - λ space of flux tubes. This work was sponsored in part by the US DOE Grant DE-SC0010340.

  1. Magnetization of a Current-Carrying Superconducting Disk with B-Dependent Critical Current Density

    Science.gov (United States)

    Sohrabi, Mahdi; Babaei-Brojeny, Ali A.

    2010-11-01

    In the frame work of the critical state model (CSM), the magnetic response of a thin type-II superconducting disk that carries a radial transport current and is subjected to an applied magnetic field have been studied. To this end, we have studied the process of the magnetic flux-penetration. For a disk initially containing no magnetic flux but carrying a radial current, when a perpendicular magnetic field is applied, magnetic flux-penetration occurs in three stages: (1) the magnetic flux gradually penetrates from the edges of the disk until an instability occurs, (2) there is a rapid inflow of magnetic flux into the disk’s central region, which becomes resistive, and (3) magnetic flux continues to enter the disk, while persistent azimuthal currents flow in an outer annular region where the net current density is equal to J c . Also the behavior of a current-carrying disk subjected to an AC magnetic field is calculated. The magnetic flux, the current profiles and the magnetization hysteresis loops are calculated for several commonly used J c ( B) dependences. Finally, the results of the applications of the local field-dependent of the critical current density J c ( B) are compared with those obtained from the Bean model.

  2. Ion-Cyclotron Instability in Current-Carrying Lorentzian (Kappa) and Maxwellian Plasmas with Anisotropic Temperatures: A Comparative Study

    Science.gov (United States)

    2011-09-26

    in the solar wind and in many space plasmas often exhibit non - Maxwellian suprathermal tails that decrease as a power-law of the velocity.1 Such...AFRL-RV-PS- AFRL-RV-PS- TR-2011-0164 TR-2011-0164 ION-CYCLOTRON INSTABILITY IN CURRENT- CARRYING LORENTZIAN (KAPPA) AND MAXWELLIAN PLASMAS...1 Oct 2007 – 9 Sep 2011 4. TITLE AND SUBTITLE Ion-Cyclotron Instability in Current-Carrying Lorentzian (Kappa) and Maxwellian Plasmas 5a. CONTRACT

  3. Comparing a current-carrying circular wire with polygons of equal perimeter; Magnetic field versus magnetic flux

    OpenAIRE

    J P Silva; Silvestre, A. J.

    2006-01-01

    We compare the magnetic field at the center of and the self-magnetic flux through a current-carrying circular loop, with those obtained for current-carrying polygons with the same perimeter. As the magnetic field diverges at the position of the wires, we compare the self-fluxes utilizing several regularization procedures. The calculation is best performed utilizing the vector potential, thus highlighting its usefulness in practical applications. Our analysis answers some of the intuition chal...

  4. Guiding Neutral Atoms with Two Current-Carrying Wires and a Vertical Bias Field on the Atom Chip

    Institute of Scientific and Technical Information of China (English)

    KE Min; YAN Bo; LI Xiao-Lin; WANG Yu-Zhu

    2008-01-01

    @@ We demonstrate the guiding of neutral atoms with two parallel microfabricated current-carrying wires on the atom chip and a verticai magnetic bias field.The atoms are guided along a magnetic field minimum parallel to the current-carrying wires and confined in the other two directions.We describe in detail how the precooled atoms are efficiently loaded into the two-wire guide.

  5. Thermal Model of a Current-Carrying Wire in a Vacuum

    Science.gov (United States)

    Border, James

    2006-01-01

    A computer program implements a thermal model of an insulated wire carrying electric current and surrounded by a vacuum. The model includes the effects of Joule heating, conduction of heat along the wire, and radiation of heat from the outer surface of the insulation on the wire. The model takes account of the temperature dependences of the thermal and electrical properties of the wire, the emissivity of the insulation, and the possibility that not only can temperature vary along the wire but, in addition, the ends of the wire can be thermally grounded at different temperatures. The resulting second-order differential equation for the steady-state temperature as a function of position along the wire is highly nonlinear. The wire is discretized along its length, and the equation is solved numerically by use of an iterative algorithm that utilizes a multidimensional version of the Newton-Raphson method.

  6. Comparing a current-carrying circular wire with polygons of equal perimeter: magnetic field versus magnetic flux

    Science.gov (United States)

    Silva, J. P.; Silvestre, A. J.

    2005-09-01

    We compare the magnetic field at the centre and the self-magnetic flux through a current-carrying circular loop, with those obtained for current-carrying polygons with the same perimeter. As the magnetic field diverges at the position of the wires, we compare the self-fluxes utilizing several regularization procedures. The calculation is best performed utilizing the vector potential, thus highlighting its usefulness in practical applications. Our analysis answers some of the intuition challenges students face when they encounter a related simple textbook example. These results can be applied directly to the determination of mutual inductances in a variety of situations.

  7. Deformation of the free surface of a conducting fluid in the magnetic field of current-carrying linear conductors

    Science.gov (United States)

    Zubarev, N. M.; Zubareva, O. V.

    2017-06-01

    The magnetic shaping problem is studied for the situation where a cylindrical column of a perfectly conducting fluid is deformed by the magnetic field of a system of linear current-carrying conductors. Equilibrium is achieved due to the balance of capillary and magnetic pressures. Two two-parametric families of exact solutions of the problem are obtained with the help of conformal mapping technique. In accordance with them, the column essentially deforms in the cross section up to its disintegration.

  8. Magnetic Field Due to a Finite Length Current-Carrying Wire Using the Concept of Displacement Current

    Science.gov (United States)

    Buschauer, Robert

    2014-01-01

    In undergraduate E&M courses the magnetic field due to a finite length, current-carrying wire can be calculated using the Biot-Savart law. However, to the author's knowledge, no textbook presents the calculation of this field using the Ampere-Maxwell law: ?B [multiplied by] dl = µ[subscript 0] (I + e[subscript 0] dF/dt) [multiplied by] 1

  9. Acceleration of electric current-carrying string loop near a Schwarzschild black hole immersed in an asymptotically uniform magnetic field

    CERN Document Server

    Tursunov, Arman; Stuchlík, Zdeněk; Ahmedov, Bobomurat

    2014-01-01

    We study the acceleration of an electric current-carrying and axially-symmetric string loop initially oscillating in the vicinity of a Schwarzschild black hole embedded in an external asymptotically uniform magnetic field. The plane of the string loop is orthogonal to the magnetic field lines and the acceleration of the string loop occurs due to the transmutation effect turning in the deep gravitational field the internal energy of the oscillating strings to the energy of their translational motion along the axis given by the symmetry of the black hole spacetime and the magnetic field. We restrict our attention to the motion of string loop with energy high enough, when it can overcome the gravitational attraction and escape to infinity. We demonstrate that for the current-carrying string loop the transmutation effect is enhanced by the contribution of the interaction between the electric current of the string loop and the external magnetic field and we give conditions that have to be fulfilled for an efficien...

  10. The quantum-mechanical basis of an extended Landau-Lifshitz-Gilbert equation for a current-carrying ferromagnetic wire.

    Science.gov (United States)

    Edwards, D M; Wessely, O

    2009-04-08

    An extended Landau-Lifshitz-Gilbert (LLG) equation is introduced to describe the dynamics of inhomogeneous magnetization in a current-carrying wire. The coefficients of all the terms in this equation are calculated quantum-mechanically for a simple model which includes impurity scattering. This is done by comparing the energies and lifetimes of a spin wave calculated from the LLG equation and from the explicit model. Two terms are of particular importance since they describe non-adiabatic spin-transfer torque and damping processes which do not rely on spin-orbit coupling. It is shown that these terms may have a significant influence on the velocity of a current-driven domain wall and they become dominant in the case of a narrow wall.

  11. Dynamics of current-carrying string loops in the Kerr naked-singularity and black-hole spacetimes

    CERN Document Server

    Kološ, M

    2013-01-01

    Current-carrying string-loop dynamics is studied in the Kerr spacetimes. With attention concentrated to the axisymmetric motion of string loops around symmetry axis of both black-hole (BH) and naked singularity (NS) spacetimes, it is shown that the resulting motion is governed by the presence of an outer tension barrier and an inner angular momentum barrier that are influenced by the BH or NS spin. We classify the string dynamics according to properties of the energy boundary function (effective potential) for the string loop motion. We have found that for NS there exist new types of energy boundary function, namely those with off-equatorial minima. Conversion of the energy of the string oscillations to the energy of the linear translational motion has been studied. Such a transmutation effect is much more efficient in the NS spacetimes because lack of the event horizon. For BH spacetimes efficiency of the transmutation effect is only weakly spin dependent. Transition from regular to chaotic regime of the str...

  12. Studies about the current carrying capacity of the devices of the electric power transmission depending on the ambient conditions; Untersuchungen zur Strombelastbarkeit der Geraete der Elektroenergieuebertragung unter Freiluftatmosphaere

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Ina

    2011-07-01

    Due to the liberalization of the electricity market and the increasing expansion of the generation of wind power the transport of electric power in the power grid is increasing. Due to that the electrical equipment is loaded higher up to its thermal limits. However the electrical power supply should be anytime reliable. Because the new construction and upgrade of overhead lines and substations is expensive and approval procedures can take up to ten years, solutions have to be found, to ensue in short and medium term the transport of electrical power through the power grid. In this paper a possibility is introduced and analyzed to increase the current carrying capacity of the electrical equipment without carrying out extensive reconstructions or new buildings. For that the method of thermal networks is used. For the different devices of the electric power transmission (overhead lines, electrical fittings, circuit-breaker, disconnecting switch and current transformer) thermal networks are designed. The heating on examples of all devices was studied and tested under laboratory conditions and the thermal networks were verified. By expansion of the thermal networks with elements for forced convection (wind velocity) and additional heat sources (solar radiation) the ambient conditions were considered. With the help of the so expanded thermal networks parameter studies depending on the wind velocity, ambient temperature and solar radiation were carried out. The studies showed that depending on the ambient conditions the current carrying capacity of all devices can be increased without changing the devices. The rated currents of all devices are specified for a high ambient temperature (e.g. 35 C) and low wind speed (e.g. 1 m/s). Most of the time in a year the ambient temperature is lower and the wind speed is higher than the specified values. So the devices can carry a higher current than the rated current without exceeding its thermal limits. The calculations show the

  13. The direct relationship between output power and current carrying capability of rotor bars in HTS induction/synchronous motor with the use of DI-BSCCO tapes

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, T; Nagao, K; Nishimura, T; Ogama, Y; Kawamoto, M [Department of Electrical Engineering, Graduate School of Engineering, Kyoto University, 1 Kyoto-Daigaku Katsura, Nishikyo-Ku, Kyoto 615-8510 (Japan); Okazaki, T; Ayai, N; Oyama, H [Electric Power and Energy Research Laboratories, Sumitomo Electric Industries, Ltd, 1-1-3, Shimaya, Konohaya-Ku, Osaka 554-0024 (Japan)], E-mail: tk_naka@kuee.kyoto-u.ac.jp

    2008-08-15

    We report on the direct relationship between output power and the current carrying capability of a squirrel-cage HTS induction/synchronous motor based on experiment. The secondary windings are fabricated by use of so-called DI-BSCCO tapes, and the conventional (normal conducting) stator, three-phase and four-pole, is utilized. The tests are carried out in liquid nitrogen for two kinds of HTS windings, in which the number of HTS rotor bars is varied. It is directly shown that the output power is proportional to the rotor bars' critical current at 77 K. In other words, the torque can be enlarged by increasing the critical current of the HTS rotor bars.

  14. A Deep Analysis of the Magnetic Field Produced by a Current-Carrying Straight Solenoid%长直螺线管磁场的深入分析

    Institute of Scientific and Technical Information of China (English)

    曾晓英; 杨昌虎; 杨昶

    2001-01-01

    将长直螺线管磁场看作直线电流磁场和圆线圈电流磁场迭加。在此基础上,对螺线管磁场进行了深入分析和精确计算,给出了一般情形下近似描述长直螺线管磁场需满足的结构条件。%Decomposing the magnetic filed of a current-carrying strainght solenoid into that of straight current and that of circular curr ent, deep analysis and exact calculation of the field are proposed, and the approximation conditions have been derived for the description of the magnetic field of a straight solenoid in simplified case.

  15. RANDOM VIBRATION OF A CURRENT CARRYING CIRCULAR PLATE IN MAGNETIC FIELD%载流圆板的磁弹性随机振动

    Institute of Scientific and Technical Information of China (English)

    王平; 李晓靓; 白象忠

    2012-01-01

    The magnetic-elastic random vibration problem of a current-carrying circular plate in a magnetic field is studied. Based on the magneto-elastic theory and the random vibration theory of a continue system with distributed parameters, the magneto-elastic random vibration equation of a current carrying circular plate in a magnetic field was derived. The stochastic response analysis of the circular plate in a magnetic field was finished. The auto-correlation function, power spectral density function and the mean function of the random displacement response of the circular plate in a magnetic field were obtained. In a specific example, the power spectral density function of the displacement response of the circular plate with stationary random current was calculated.%分析载流圆板在磁场中的磁弹性随机振动问题.根据薄板、薄壳体的磁弹性运动方程和连续体的随机振动理论,导出在磁场环境中圆板的磁弹性随机振动方程.对磁场中的载流圆板进行随机响应分析,得到圆板位移响应的自相关函数、功率谱密度函数及均值函数等数字特征.通过具体算例,对处于外加磁场中通入平稳随机电流的导电圆板,计算其位移响应的功率谱密度函数.

  16. 载流梁的热磁弹性3次超谐共振%Third Superharmonic Resonance of the Current-Carrying Beam in Thermal-Magneto-Elasticity Field

    Institute of Scientific and Technical Information of China (English)

    席晓燕

    2014-01-01

    在磁弹性动力学理论的基础上,应用动力学方法建立电磁场和温度场联合作用下的载流梁的非线性热磁弹性振动方程。应用非线性振动的多尺度法,求得了系统受Lorentz力和温度影响共同作用的3次超谐共振幅频响应方程,并对其进行了数值计算,研究电磁场、温度变化、电流、几何参数等参数对载流梁3次超谐共振响应曲线的影响。结果表明:当温度、磁场强度、长度、横截面积达到特定值时,系统振幅会大幅增加。%Based on the electro-magneto-elastic theory, nonlinear vibration equation of current-carrying beam in thermal-magneto-elasticity field is studied. The Lorentz force and temperature effect on the beam are derived. According to the method of multiple scales for nonlinear vibrations the amplitude frequency response equation of third superharmonic resonance is obtained. The effects of electro-magnetic and mechanical parameters on system res-onance characteristics are analyzed. The results show the amplitude of system will substantially increase when the temperature,magnetic field intensity,length,cross-sectional area reach their certain values respectively.

  17. Elementary operators - still not elementary?

    Directory of Open Access Journals (Sweden)

    Martin Mathieu

    2016-01-01

    Full Text Available Properties of elementary operators, that is, finite sums of two-sided multiplications on a Banach algebra, have been studied under a vast variety of aspects by numerous authors. In this paper we review recent advances in a new direction that seems not to have been explored before: the question when an elementary operator is spectrally bounded or spectrally isometric. As with other investigations, a number of subtleties occur which show that elementary operators are still not elementary to handle.

  18. Forced vibrations of a current-carrying nanowire in a longitudinal magnetic field accounting for both surface energy and size effects

    Science.gov (United States)

    Kiani, Keivan

    2014-09-01

    Forced vibrations of current-carrying nanowires in the presence of a longitudinal magnetic field are of interest. By considering the surface energy and size effects, the coupled equations of motion describing transverse motions of the nanostructure are derived. By employing Galerkin and Newmark-β approaches, the deflections of the nanowire subjected to transverse dynamic loads are evaluated. The effects of the magnetic field, electric current, pre-tension force, frequency of the applied load, surface and size effects on the maximum transverse displacements are discussed. The obtained results display that for the frequency of the applied load lower than the nanowire's fundamental frequency, by increasing the magnetic field or electric current, the maximum transverse displacements would increase. However, for exciting frequencies greater than that of the nanowire, maximum transverse displacements would increase or decrease with the magnetic field strength or electric current. Additionally, the pre-tension force results in decreasing of the maximum transverse displacements. Such a reduction is more apparent for higher values of the magnetic field strength and electric current. The present study would be useful in the design of the micro- and nano-electro-mechanical systems expected to be one of the most wanted technologies in the near future.

  19. Evolution of the Coronal Magnetic Configurations Including a Current-Carrying Flux Rope in Response to the Change in the Background Field

    CERN Document Server

    Wang, Hong-Juan; Gong, Jian-Cun; Lin, Jun

    2014-01-01

    We investigate equilibrium height of the flux rope, and its internal equilibrium in a realistic plasma environment by carrying out numerical simulations of the evolution of systems including a current-carrying flux rope. We find that the equilibrium height of the flux rope is approximately a power-law function of the relative strength of the background field. Our simulations indicate that the flux rope can escape more easily from a weaker background field. This further confirms the catastrophe in the magnetic configuration of interest can be triggered by decrease of strength of the background field. Our results show that it takes some time to reach internal equilibrium depending on the initial state of the flux rope. The plasma flow inside the flux rope due to the adjustment for the internal equilibrium of the flux rope remains small and does not last very long when the initial state of the flux rope commences from the stable branch of the theoretical equilibrium curve. This work also confirms the influence o...

  20. Nonlinear dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Turchetti, G. (Bologna Univ. (Italy). Dipt. di Fisica)

    1989-01-01

    Research in nonlinear dynamics is rapidly expanding and its range of applications is extending beyond the traditional areas of science where it was first developed. Indeed while linear analysis and modelling, which has been very successful in mathematical physics and engineering, has become a mature science, many elementary phenomena of intrinsic nonlinear nature were recently experimentally detected and investigated, suggesting new theoretical work. Complex systems, as turbulent fluids, were known to be governed by intrinsically nonlinear laws since a long time ago, but received purely phenomenological descriptions. The pioneering works of Boltzmann and Poincare, probably because of their intrinsic difficulty, did not have a revolutionary impact at their time; it is only very recently that their message is reaching a significant number of mathematicians and physicists. Certainly the development of computers and computer graphics played an important role in developing geometric intuition of complex phenomena through simple numerical experiments, while a new mathematical framework to understand them was being developed.

  1. Current-carrying element based on second-generation high-temperature superconductor for the magnet system of a fusion neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Novikov, M. S., E-mail: mihailnovikov@yandex.ru; Ivanov, D. P., E-mail: Ivanov-DP@nrcki.ru, E-mail: denis.ivanov30@mail.ru; Novikov, S. I., E-mail: novikov-si@nrcki.ru; Shuvaev, S. A., E-mail: ser-shuvaev@yandex.ru, E-mail: sergey.shuvaev@phystech.edu [National Research Center Kurchatov Institute (Russian Federation)

    2015-12-15

    Application of current-carrying elements (CCEs) made of second-generation high-temperature superconductor (2G HTS) in magnet systems of a fusion neutron source (FNS) and other fusion devices will allow their magnetic field and thermodynamic stability to be increased substantially in comparison with those of low-temperature superconductor (LTS) magnets. For a toroidal magnet of the FNS, a design of a helical (partially transposed) CCE made of 2G HTS is under development with forced-flow cooling by helium gas, a current of 20–30 kA, an operating temperature of 10–20 K, and a magnetic field on the winding of 12–15 T (prospectively ∼20 T). Short-sized samples of the helical flexible heavy-current CCE are being fabricated and investigated; a pilot-line unit for production of long-sized CCE pieces is under construction. The applied fabrication technique allows the CCE to be produced which combines a high operating current, thermal and mechanical stability, manufacturability, and low losses in the alternating modes. The possibility of fabricating the CCE with the outer dimensions and values of the operating parameter required for the FNS (and with a significant margin) using already available serial 2G HTS tapes is substantiated. The maximum field of toroidal magnets with CCEs made of 2G HTS will be limited only by mechanical properties of the magnet’s casing and structure, while the thermal stability will be approximately two orders of magnitude higher than that of toroidal magnets with LTS-based CCEs. The helical CCE made of 2G HTS is very promising for fusion and hybrid electric power plants, and its design and technologies of production, as well as the prototype coils made of it for the FNS and other tokamaks, are worth developing now.

  2. Elementary algebra

    CERN Document Server

    McKeague, Charles P

    1981-01-01

    Elementary Algebra 2e, Second Edition focuses on the basic principles, operations, and approaches involved in elementary algebra. The book first tackles the basics, linear equations and inequalities, and graphing and linear systems. Discussions focus on the substitution method, solving linear systems by graphing, solutions to linear equations in two variables, multiplication property of equality, word problems, addition property of equality, and subtraction, addition, multiplication, and division of real numbers. The manuscript then examines exponents and polynomials, factoring, and rational e

  3. Elementary algebra

    CERN Document Server

    McKeague, Charles P

    1986-01-01

    Elementary Algebra, Third Edition focuses on the basic principles, operations, and approaches involved in elementary algebra. The book first ponders on the basics, linear equations and inequalities, and graphing and linear systems. Discussions focus on the elimination method, solving linear systems by graphing, word problems, addition property of equality, solving linear equations, linear inequalities, addition and subtraction of real numbers, and properties of real numbers. The text then takes a look at exponents and polynomials, factoring, and rational expressions. Topics include reducing ra

  4. Radial excitations of current-carrying vortices

    Science.gov (United States)

    Hartmann, Betti; Michel, Florent; Peter, Patrick

    2017-04-01

    We report on the existence of a new type of cosmic string solutions in the Witten model with U (1) × U (1) symmetry. These solutions are superconducting with radially excited condensates that exist for both gauged and ungauged currents. Our results suggest that these new configurations can be macroscopically stable, but microscopically unstable to radial perturbations. Nevertheless, they might have important consequences for the network evolution and particle emission. We discuss these effects and their possible signatures. We also comment on analogies with non-relativistic condensed matter systems where these solutions may be observable.

  5. Nonlinear Optical Rectennas

    CERN Document Server

    Stolz, A; Markey, L; Francs, G Colas des; Bouhelier, A

    2013-01-01

    We introduce strongly-coupled optical gap antennas to interface optical radiation with current-carrying electrons at the nanoscale. The transducer relies on the nonlinear optical and electrical properties of an optical antenna operating in the tunneling regime. We discuss the underlying physical mechanisms controlling the conversion and demonstrate that a two-wire optical antenna can provide advanced optoelectronic functionalities beyond tailoring the electromagnetic response of a single emitter. Interfacing an electronic command layer with a nanoscale optical device may thus be facilitated by the optical rectennas discussed here.

  6. Elementary analysis

    CERN Document Server

    Snell, K S; Langford, W J; Maxwell, E A

    1966-01-01

    Elementary Analysis, Volume 2 introduces several of the ideas of modern mathematics in a casual manner and provides the practical experience in algebraic and analytic operations that lays a sound foundation of basic skills. This book focuses on the nature of number, algebraic and logical structure, groups, rings, fields, vector spaces, matrices, sequences, limits, functions and inverse functions, complex numbers, and probability. The logical structure of analysis given through the treatment of differentiation and integration, with applications to the trigonometric and logarithmic functions, is

  7. Elementary vectors

    CERN Document Server

    Wolstenholme, E Œ

    1978-01-01

    Elementary Vectors, Third Edition serves as an introductory course in vector analysis and is intended to present the theoretical and application aspects of vectors. The book covers topics that rigorously explain and provide definitions, principles, equations, and methods in vector analysis. Applications of vector methods to simple kinematical and dynamical problems; central forces and orbits; and solutions to geometrical problems are discussed as well. This edition of the text also provides an appendix, intended for students, which the author hopes to bridge the gap between theory and appl

  8. 弥散铜导电条的制备及其组织性能分析%Preparation of ODSC Current-carrying Plate and Analysis of Its Microstructure and Properties

    Institute of Scientific and Technical Information of China (English)

    岳灿甫; 陈会东; 雷竹芳; 金建新; 陈派明

    2012-01-01

    使用雾化法制备铜-铝合金粉,采用内氧化法制备锭坯,热挤压锭坯制备弥散铜棒材,然后经拉伸和轧制棒材法制备弥散铜导电条,并对Al2O3弥散强化铜合金导电条的组织与性能进行了分析.结果表明,制备的弥散铜导电条厚1~25 mm,制备的弥散铜导电条中铝含量分别为0.19%、0.12%; 0.12%Al含量的弥散铜导电条抗拉强度为495 MPa,导电率≥92%IACS;0.19%Al含量的弥散铜导电条抗拉强度为530 MPa,导电率≥87%IACS.%The ingot of aluminum oxide dispersion strengthened copper alloy (ODSC) was produced by using atomized Cu-Al powder by adopting internal oxidation method. The rods were produced by hot extrusion method. The current-carrying plate was produced by cold drawing the rods and then cold rolling. The size of ODSC current-carrying plate was 1 -25 mm. The produced plates had two brand with 0.12%Al, 0.19%Al. Tensile strength of the copper alloy with 0.12%Al is 495 Mpa, and its conductivity is more than 92%1ACS; the tensile strength of the copper alloy with 0.19% Al is 530 Mpa, and its conductivity is 87%IACS.

  9. Input saturation in nonlinear multivariable processes resolved by nonlinear decoupling

    Directory of Open Access Journals (Sweden)

    Jens G. Balchen

    1995-04-01

    Full Text Available A new method is presented for the resolution of the problem of input saturation in nonlinear multivariable process control by means of elementary nonlinear decoupling (END. Input saturation can have serious consequences particularly in multivariable control because it may lead to very undesirable system behaviour and quite often system instability. Many authors have searched for systematic techniques for designing multivariable control systems in which saturation may occur in any of the control variables (inputs, manipulated variables. No generally accepted method seems to have been presented so far which gives a solution in closed form. The method of elementary nonlinear decoupling (END can be applied directly to the case of saturation control variables by deriving as many control strategies as there are combinations of saturating control variables. The method is demonstrated by the multivariable control of a simulated Fluidized Catalytic Cracker (FCC with very convincing results.

  10. Elementary Mathematics Leaders

    Science.gov (United States)

    Fennell, Francis; Kobett, Beth McCord; Wray, Jonathan A.

    2013-01-01

    Elementary school mathematics leaders often come to the realization that their position, however titled and determined, although dedicated to addressing needs in math teaching and learning, also entails and directly involves leadership. Elementary school math specialists/instructional leaders (referenced here as elementary mathematics leaders, or…

  11. Running Characteristics Analysis of Electromagnetic Coil Launcher With Current-carrying Armature%载流电枢电磁线圈发射器运行特性分析

    Institute of Scientific and Technical Information of China (English)

    金洪波; 曹延杰; 王成学; 王慧锦

    2016-01-01

    The armature is the key part for energy exchange in electromagnetic coil launcher (EMCL).The structural model with series-current armature launcher ( SCCAL ) and parallel-current armature launcher ( PCCAL) was proposed .System differential equation was deduced by analyzing the working principle and the structure character of two kinds of current-carrying armature launcher ( CCAL) .Systematical model of the CCAL was built with MATLAB , and the launching character was analyzed .The analysis shows that there is no pulling effect in launching process in CCAL .SCCAL is more suitable for accelerating payload with low-velocity less than 20 m/s by using low-voltage-capacitor power-supply .PCCAL can be used to accelerating payload with high velocity more over 50 m/s by using high-voltage-capacitor power-supply . The conclusion has great significance for guiding the structural design in EMCL .%电枢是电磁线圈发射器能量转换的关键部分,以此为研究对象,提出串联载流电枢发射器和并联载流电枢发射器的结构模型,通过分析2种载流电枢发射器的工作原理和结构特点,得到了系统微分方程,并利用MATLAB建立了载流电枢发射器的系统仿真模型,分析了发射器的运行特性。分析结果表明,载流电枢发射器发射过程无拖拽效应,串联载流电枢发射器适于载荷在20 m/s以下的加速段使用,适于选用低压的电容器电源;并联载流电枢发射器可用于载荷在50 m/s以上的加速段使用,适于选用高电压电容器。研究结果对电磁线圈发射器电枢结构设计具有一定的指导意义。

  12. ELEMENTARY PARTICLES AS SIGNS

    OpenAIRE

    Chiatti, Leonardo

    2014-01-01

    C.S. Peirce’s semiotic approach admits the possibility of natural signic systems. This article explores the possible connection between the concept of elementary particle and the irreducible relations of Peircean semiotics. The potentialities and the limitations of a semiotic vision of elementary physical processes are addressed.

  13. Elementary Teachers' Perceptions of Elementary Principals' Effectiveness

    Science.gov (United States)

    Fridenvalds, Kriss R.

    2012-01-01

    This dissertation examined the beliefs of elementary teachers to determine if their perceptions of effective principal leadership align to transformational leadership theory vis-a-vis the Educational Leadership Policy Standards (ELPS). A phenomenological, single-case study approach was utilized by means of a mixed-methodological, Web-based survey,…

  14. Nonlinear optics

    CERN Document Server

    Bloembergen, Nicolaas

    1996-01-01

    Nicolaas Bloembergen, recipient of the Nobel Prize for Physics (1981), wrote Nonlinear Optics in 1964, when the field of nonlinear optics was only three years old. The available literature has since grown by at least three orders of magnitude.The vitality of Nonlinear Optics is evident from the still-growing number of scientists and engineers engaged in the study of new nonlinear phenomena and in the development of new nonlinear devices in the field of opto-electronics. This monograph should be helpful in providing a historical introduction and a general background of basic ideas both for expe

  15. Nonlinear supratransmission

    Energy Technology Data Exchange (ETDEWEB)

    Geniet, F; Leon, J [Physique Mathematique et Theorique, CNRS-UMR 5825, 34095 Montpellier (France)

    2003-05-07

    A nonlinear system possessing a natural forbidden band gap can transmit energy of a signal with a frequency in the gap, as recently shown for a nonlinear chain of coupled pendulums (Geniet and Leon 2002 Phys. Rev. Lett. 89 134102). This process of nonlinear supratransmission, occurring at a threshold that is exactly predictable in many cases, is shown to have a simple experimental realization with a mechanical chain of pendulums coupled by a coil spring. It is then analysed in more detail. First we go to different (nonintegrable) systems which do sustain nonlinear supratransmission. Then a Josephson transmission line (a one-dimensional array of short Josephson junctions coupled through superconducting wires) is shown to also sustain nonlinear supratransmission, though being related to a different class of boundary conditions, and despite the presence of damping, finiteness, and discreteness. Finally, the mechanism at the origin of nonlinear supratransmission is found to be a nonlinear instability, and this is briefly discussed here.

  16. Elementary particle theory

    Energy Technology Data Exchange (ETDEWEB)

    Marciano, W.J.

    1984-12-01

    The present state of the art in elementary particle theory is reviewed. Topics include quantum electrodynamics, weak interactions, electroweak unification, quantum chromodynamics, and grand unified theories. 113 references. (WHK)

  17. Experiment in Elementary Statistics

    Science.gov (United States)

    Fernando, P. C. B.

    1976-01-01

    Presents an undergraduate laboratory exercise in elementary statistics in which students verify empirically the various aspects of the Gaussian distribution. Sampling techniques and other commonly used statistical procedures are introduced. (CP)

  18. Elementary particle physics

    Science.gov (United States)

    Perkins, D. H.

    1986-01-01

    Elementary particle physics is discussed. Status of the Standard Model of electroweak and strong interactions; phenomena beyond the Standard Model; new accelerator projects; and possible contributions from non-accelerator experiments are examined.

  19. Practical Nonlinearities

    Science.gov (United States)

    2016-07-01

    Advanced Research Projects Agency (DARPA) Dynamics-Enabled Frequency Sources (DEFYS) program is focused on the convergence of nonlinear dynamics and...Early work in this program has shown that nonlinear dynamics can provide performance advantages. However, the pathway from initial results to...dependent nonlinear stiffness observed in these devices. This work is ongoing, and will continue through the final period of this program . Reference 9

  20. Nonlinear oscillations

    CERN Document Server

    Nayfeh, Ali Hasan

    1995-01-01

    Nonlinear Oscillations is a self-contained and thorough treatment of the vigorous research that has occurred in nonlinear mechanics since 1970. The book begins with fundamental concepts and techniques of analysis and progresses through recent developments and provides an overview that abstracts and introduces main nonlinear phenomena. It treats systems having a single degree of freedom, introducing basic concepts and analytical methods, and extends concepts and methods to systems having degrees of freedom. Most of this material cannot be found in any other text. Nonlinear Oscillations uses sim

  1. Nonlinear Science

    CERN Document Server

    Yoshida, Zensho

    2010-01-01

    This book gives a general, basic understanding of the mathematical structure "nonlinearity" that lies in the depths of complex systems. Analyzing the heterogeneity that the prefix "non" represents with respect to notions such as the linear space, integrability and scale hierarchy, "nonlinear science" is explained as a challenge of deconstruction of the modern sciences. This book is not a technical guide to teach mathematical tools of nonlinear analysis, nor a zoology of so-called nonlinear phenomena. By critically analyzing the structure of linear theories, and cl

  2. Nonlinear analysis

    CERN Document Server

    Nanda, Sudarsan

    2013-01-01

    "Nonlinear analysis" presents recent developments in calculus in Banach space, convex sets, convex functions, best approximation, fixed point theorems, nonlinear operators, variational inequality, complementary problem and semi-inner-product spaces. Nonlinear Analysis has become important and useful in the present days because many real world problems are nonlinear, nonconvex and nonsmooth in nature. Although basic concepts have been presented here but many results presented have not appeared in any book till now. The book could be used as a text for graduate students and also it will be useful for researchers working in this field.

  3. Nonlinear generalized functions and nonlinear numerical simulations in fluid and solid continuum mechanics

    OpenAIRE

    Colombeau, J. F.

    2007-01-01

    We present numerical techniques based on generalized functions adapted to nonlinear calculations. They concern main numerical engineering problems ruled by-or issued from-nonlinear equations of continuum mechanics. The aim of this text is to invite the readers in applying these techniques in their own work without significant prerequisites by presenting their use on a sample of elementary applications from engineering. Pure mathematicians can read it easily since the numerical techniques are ...

  4. Describing Elementary Certification Methods across the Elementary Music Career Cycle

    Science.gov (United States)

    Svec, Christina L.

    2017-01-01

    The purpose of the study was to describe elementary music method choice and certification method choice overall and across the elementary music career cycle. Participants (N = 254) were categorized as Level I or Elementary Division in a southwestern music education association database. The questionnaire included 25 four-point Likert-type items…

  5. Fractions in elementary education

    CERN Document Server

    Quinn, Frank

    2013-01-01

    This paper is one of a series in which elementary-education practice is analyzed by comparison with the history of mathematics, mathematical structure, modern practice, and (occasionally) cognitive neuroscience. The primary concerns are: Why do so many children find elementary mathematics difficult? And, why are the ones who succeed still so poorly prepared for college material needed for technical careers? The answer provided by conventional wisdom is essentially that mathematics is difficult. Third-graders are not developmentally ready for the subtlety of fractions, for instance, and even high-performing students cannot be expected to develop the skills of experienced users. However we will see that this is far from the whole story and is probably wrong: elementary-education fractions are genuinely harder and less effective than the version employed by experienced users. Experts discard at least 90% of what is taught in schools. Our educational system is actually counterproductive for skill development, and...

  6. Elementary number theory

    CERN Document Server

    Dudley, Underwood

    2008-01-01

    Ideal for a first course in number theory, this lively, engaging text requires only a familiarity with elementary algebra and the properties of real numbers. Author Underwood Dudley, who has written a series of popular mathematics books, maintains that the best way to learn mathematics is by solving problems. In keeping with this philosophy, the text includes nearly 1,000 exercises and problems-some computational and some classical, many original, and some with complete solutions. The opening chapters offer sound explanations of the basics of elementary number theory and develop the fundamenta

  7. Elementary cycles of time

    Directory of Open Access Journals (Sweden)

    Dolce Donatello

    2013-09-01

    Full Text Available Elementary particles, i.e. the basic constituents of nature, are characterized by quantum recurrences in time. The flow of time of every physical system can be therefore decomposed in elementary cycles of time. This allows us to enforce the local nature of relativistic time, yielding interesting unified descriptions of fundamental aspects of modern physics, as shown in recent publications. Every particle can be regarded as a reference clock with time resolution of the order of the Compton time particle, many orders of magnitude more accurate than the atomic clocks. Here we report basic implications about the resulting notion of time.

  8. Logic in elementary mathematics

    CERN Document Server

    Exner, Robert M

    2011-01-01

    This applications-related introductory treatment explores facets of modern symbolic logic useful in the exposition of elementary mathematics. The authors convey the material in a manner accessible to those trained in standard elementary mathematics but lacking any formal background in logic. Topics include the statement calculus, proof and demonstration, abstract mathematical systems, and the restricted predicate calculus. The final chapter draws upon the methods of logical reasoning covered in previous chapters to develop solutions of linear and quadratic equations, definitions of order and

  9. Elementary classical hydrodynamics

    CERN Document Server

    Chirgwin, B H; Langford, W J; Maxwell, E A; Plumpton, C

    1967-01-01

    Elementary Classical Hydrodynamics deals with the fundamental principles of elementary classical hydrodynamics, with emphasis on the mechanics of inviscid fluids. Topics covered by this book include direct use of the equations of hydrodynamics, potential flows, two-dimensional fluid motion, waves in liquids, and compressible flows. Some general theorems such as Bernoulli's equation are also considered. This book is comprised of six chapters and begins by introducing the reader to the fundamental principles of fluid hydrodynamics, with emphasis on ways of studying the motion of a fluid. Basic c

  10. Elementary topology problem textbook

    CERN Document Server

    Viro, O Ya; Netsvetaev, N Yu; Kharlamov, V M

    2008-01-01

    This textbook on elementary topology contains a detailed introduction to general topology and an introduction to algebraic topology via its most classical and elementary segment centered at the notions of fundamental group and covering space. The book is tailored for the reader who is determined to work actively. The proofs of theorems are separated from their formulations and are gathered at the end of each chapter. This makes the book look like a pure problem book and encourages the reader to think through each formulation. A reader who prefers a more traditional style can either find the pr

  11. Nonlinear Reconstruction

    CERN Document Server

    Zhu, Hong-Ming; Pen, Ue-Li; Chen, Xuelei; Yu, Hao-Ran

    2016-01-01

    We present a direct approach to non-parametrically reconstruct the linear density field from an observed non-linear map. We solve for the unique displacement potential consistent with the non-linear density and positive definite coordinate transformation using a multigrid algorithm. We show that we recover the linear initial conditions up to $k\\sim 1\\ h/\\mathrm{Mpc}$ with minimal computational cost. This reconstruction approach generalizes the linear displacement theory to fully non-linear fields, potentially substantially expanding the BAO and RSD information content of dense large scale structure surveys, including for example SDSS main sample and 21cm intensity mapping.

  12. Nonlinear optics

    CERN Document Server

    Boyd, Robert W

    2013-01-01

    Nonlinear Optics is an advanced textbook for courses dealing with nonlinear optics, quantum electronics, laser physics, contemporary and quantum optics, and electrooptics. Its pedagogical emphasis is on fundamentals rather than particular, transitory applications. As a result, this textbook will have lasting appeal to a wide audience of electrical engineering, physics, and optics students, as well as those in related fields such as materials science and chemistry.Key Features* The origin of optical nonlinearities, including dependence on the polarization of light* A detailed treatment of the q

  13. Urban Elementary STEM Initiative

    Science.gov (United States)

    Parker, Carolyn; Abel, Yolanda; Denisova, Ekaterina

    2015-01-01

    The new standards for K-12 science education suggest that student learning should be more integrated and should focus on crosscutting concepts and core ideas from the areas of physical science, life science, Earth/space science, and engineering/technology. This paper describes large-scale, urban elementary-focused science, technology, engineering,…

  14. Bowling for Elementary Students

    Science.gov (United States)

    Curtis, Joyce M.

    2005-01-01

    Physical education programs at the elementary school level play an important role in developing students' interest and skill in lifelong physical activities. With increasing inactivity, overweight, and obesity among children, school physical education programs are challenged with presenting activities that can be enjoyed in childhood and…

  15. Elementary, Dear Albert

    CERN Multimedia

    2017-01-01

    Elementary, Dear Albert! fiction based upon every physicist's dream: have a chat with Albert Einstein. Starring theoretical physicist Alvaro de Rujula in the role of Dr. Nuts and experimental physicist Federico Antinori in the role of Albert Einstein. Directed by Silvano de Gennaro

  16. Elementary introduction to Moonshine

    CERN Document Server

    Kachru, Shamit

    2016-01-01

    These notes provide an elementary (and incomplete) sketch of the objects and ideas involved in monstrous and umbral moonshine. They were the basis for a plenary lecture at the 18th International Congress on Mathematical Physics, and for a lecture series at the Centre International de Recontres Mathematiques school on "Mathematics of String Theory."

  17. Elementary School Principal Effectiveness.

    Science.gov (United States)

    Cross, Ray

    A review of research linking elementary principal "antecedents" (defined as traits), behaviors, school conditions, and student outcomes furnishes few supportable generalizations. The studies relating principal antecedents with behavior and principal antecedents with organizational variables reveals that the trait theory of leadership has…

  18. Quartiles in Elementary Statistics

    Science.gov (United States)

    Langford, Eric

    2006-01-01

    The calculation of the upper and lower quartile values of a data set in an elementary statistics course is done in at least a dozen different ways, depending on the text or computer/calculator package being used (such as SAS, JMP, MINITAB, "Excel," and the TI-83 Plus). In this paper, we examine the various methods and offer a suggestion for a new…

  19. Vision in elementary mathematics

    CERN Document Server

    Sawyer, W W

    2003-01-01

    Sure-fire techniques of visualizing, dramatizing, and analyzing numbers promise to attract and retain students' attention and understanding. Topics include basic multiplication and division, algebra, word problems, graphs, negative numbers, fractions, many other practical applications of elementary mathematics. 1964 ed. Answers to Problems.

  20. Elementary School Computer Literacy.

    Science.gov (United States)

    New York City Board of Education, Brooklyn, NY.

    This curriculum guide presents lessons for computer literacy instruction in the elementary grades. The first section of the guide includes 22 lessons on hardware, covering such topics as how computers work, keyboarding, word processing, and computer peripherals. The 13 lessons in the second section cover social topics related to the computer,…

  1. Bowling for Elementary Students

    Science.gov (United States)

    Curtis, Joyce M.

    2005-01-01

    Physical education programs at the elementary school level play an important role in developing students' interest and skill in lifelong physical activities. With increasing inactivity, overweight, and obesity among children, school physical education programs are challenged with presenting activities that can be enjoyed in childhood and…

  2. Nonlinear optimization

    CERN Document Server

    Ruszczynski, Andrzej

    2011-01-01

    Optimization is one of the most important areas of modern applied mathematics, with applications in fields from engineering and economics to finance, statistics, management science, and medicine. While many books have addressed its various aspects, Nonlinear Optimization is the first comprehensive treatment that will allow graduate students and researchers to understand its modern ideas, principles, and methods within a reasonable time, but without sacrificing mathematical precision. Andrzej Ruszczynski, a leading expert in the optimization of nonlinear stochastic systems, integrates t

  3. Wakes in Dilatonic Current-Carrying Cosmic Strings

    CERN Document Server

    Oliveira, A L N

    2003-01-01

    In this work, we present the gravitational field generated by a cosmic string carrying a timelike current in the scalar-tensor gravities. The mechanism of formation and evolution of wakes is fully investigated in this framework. We show that the inclusion of electromagnetic properties for the string induces logarithmic divergences in the accretion problem.

  4. Linear and nonlinear stiffness and friction in biological rhythmic movements.

    Science.gov (United States)

    Beek, P J; Schmidt, R C; Morris, A W; Sim, M Y; Turvey, M T

    1995-11-01

    Biological rhythmic movements can be viewed as instances of self-sustained oscillators. Auto-oscillatory phenomena must involve a nonlinear friction function, and usually involve a nonlinear elastic function. With respect to rhythmic movements, the question is: What kinds of nonlinear friction and elastic functions are involved? The nonlinear friction functions of the kind identified by Rayleigh (involving terms such as theta3) and van der Pol (involving terms such as theta2theta), and the nonlinear elastic functions identified by Duffing (involving terms such as theta3), constitute elementary nonlinear components for the assembling of self-sustained oscillators, Recently, additional elementary nonlinear friction and stiffness functions expressed, respectively, through terms such as theta2theta3 and thetatheta2, and a methodology for evaluating the contribution of the elementary components to any given cyclic activity have been identified. The methodology uses a quantification of the continuous deviation of oscillatory motion from ideal (harmonic) motion. Multiple regression of this quantity on the elementary linear and nonlinear terms reveals the individual contribution of each term to the oscillator's non-harmonic behavior. In the present article the methodology was applied to the data from three experiments in which human subjects produced pendular rhythmic movements under manipulations of rotational inertia (experiment 1), rotational inertia and frequency (experiment 2), and rotational inertia and amplitude (experiment 3). The analysis revealed that the pendular oscillators assembled in the three experiments were compositionally rich, braiding linear and nonlinear friction and elastic functions in a manner that depended on the nature of the task.

  5. Link between travelling waves and first order nonlinear ordinary differential equation with a sixth-degree nonlinear term

    Energy Technology Data Exchange (ETDEWEB)

    Huang Dingjiang [Department of Applied Mathematics, Dalian University of Technology, Dalian 116024 (China)]. E-mail: hdj8116@163.com; Zhang Hongqing [Department of Applied Mathematics, Dalian University of Technology, Dalian 116024 (China)

    2006-08-15

    Many travelling wave solutions of nonlinear evolution equations can be written as a polynomial in several elementary or special functions which satisfy a first order nonlinear ordinary differential equation with a sixth-degree nonlinear term. From that property, we deduce an algebraic method for constructing those solutions by determining only a finite number of coefficients. Being concise and straightforward, the method is applied to three nonlinear evolution equations. As a result, many exact travelling wave solutions are obtained which include new bell and kink profile solitary wave solutions, triangular periodic wave solutions and singular solutions.

  6. Nonlinear channelizer

    Science.gov (United States)

    In, Visarath; Longhini, Patrick; Kho, Andy; Neff, Joseph D.; Leung, Daniel; Liu, Norman; Meadows, Brian K.; Gordon, Frank; Bulsara, Adi R.; Palacios, Antonio

    2012-12-01

    The nonlinear channelizer is an integrated circuit made up of large parallel arrays of analog nonlinear oscillators, which, collectively, serve as a broad-spectrum analyzer with the ability to receive complex signals containing multiple frequencies and instantaneously lock-on or respond to a received signal in a few oscillation cycles. The concept is based on the generation of internal oscillations in coupled nonlinear systems that do not normally oscillate in the absence of coupling. In particular, the system consists of unidirectionally coupled bistable nonlinear elements, where the frequency and other dynamical characteristics of the emergent oscillations depend on the system's internal parameters and the received signal. These properties and characteristics are being employed to develop a system capable of locking onto any arbitrary input radio frequency signal. The system is efficient by eliminating the need for high-speed, high-accuracy analog-to-digital converters, and compact by making use of nonlinear coupled systems to act as a channelizer (frequency binning and channeling), a low noise amplifier, and a frequency down-converter in a single step which, in turn, will reduce the size, weight, power, and cost of the entire communication system. This paper covers the theory, numerical simulations, and some engineering details that validate the concept at the frequency band of 1-4 GHz.

  7. ELEMENTARY PARTICLE INTERACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    EFREMENKO, YURI; HANDLER, THOMAS; KAMYSHKOV, YURI; SIOPSIS, GEORGE; SPANIER, STEFAN

    2013-07-30

    The High-Energy Elementary Particle Interactions group at UT during the last three years worked on the following directions and projects: Collider-based Particle Physics; Neutrino Physics, particularly participation in “NOνA”, “Double Chooz”, and “KamLAND” neutrino experiments; and Theory, including Scattering amplitudes, Quark-gluon plasma; Holographic cosmology; Holographic superconductors; Charge density waves; Striped superconductors; and Holographic FFLO states.

  8. Elementary linear algebra

    CERN Document Server

    Andrilli, Stephen

    2010-01-01

    Elementary Linear Algebra develops and explains in careful detail the computational techniques and fundamental theoretical results central to a first course in linear algebra. This highly acclaimed text focuses on developing the abstract thinking essential for further mathematical study. The authors give early, intensive attention to the skills necessary to make students comfortable with mathematical proofs. The text builds a gradual and smooth transition from computational results to general theory of abstract vector spaces. It also provides flexbile coverage of practical applications, expl

  9. Sports in elementary school

    OpenAIRE

    Groot, De, Julie; Moolenaar, Ben; Boers, Eralt; Mombarg,, Remo

    2016-01-01

    The aim of the project is stimulating sport participation among elementary school children in the province of Friesland. The ultimate aim is to provide three hours of physical education, provided by an physical education specialist, plus two extra hours of sport activities. Part one is about describing the differences and part two is about effective interventions after school, every week. The following instruments are used during the research: Movement Assessment Battery for Children (M-ABC-2...

  10. Elementary Nonrelativistic Quantum Mechanics

    CERN Document Server

    Rosu, H C

    2000-01-01

    This is a graduate course on elementary quantum mechanics written for the benefit of undergraduate and graduate students. It is the English version of physics/0003106, which I did at the suggestion of several students from different countries. The topics included refer to the postulates of quantum mechanics, one-dimensional barriers and wells, angular momentum and spin, WKB method, harmonic oscillator, hydrogen atom, quantum scattering, and partial waves

  11. Nonlinear Systems.

    Science.gov (United States)

    Seider, Warren D.; Ungar, Lyle H.

    1987-01-01

    Describes a course in nonlinear mathematics courses offered at the University of Pennsylvania which provides an opportunity for students to examine the complex solution spaces that chemical engineers encounter. Topics include modeling many chemical processes, especially those involving reaction and diffusion, auto catalytic reactions, phase…

  12. Elementary Statistics Tables

    CERN Document Server

    Neave, Henry R

    2012-01-01

    This book, designed for students taking a basic introductory course in statistical analysis, is far more than just a book of tables. Each table is accompanied by a careful but concise explanation and useful worked examples. Requiring little mathematical background, Elementary Statistics Tables is thus not just a reference book but a positive and user-friendly teaching and learning aid. The new edition contains a new and comprehensive "teach-yourself" section on a simple but powerful approach, now well-known in parts of industry but less so in academia, to analysing and interpreting process dat

  13. Elementary Quantum Mechanics

    CERN Document Server

    Rosu, H C

    2000-01-01

    This is the first graduate course on elementary quantum mechanics in Internet written in Romanian for the benefit of Romanian speaking students (Romania and Moldova). It is a translation (with corrections) of the Spanish version of the course (physics/9808031, English translation is under consideration), which I did at the request of students of physics in Bucharest. The topics included refer to the postulates of quantum mechanics, one-dimensional barriers and wells, angular momentum and spin, WKB method, harmonic oscillator, hydrogen atom, quantum scattering, and partial waves

  14. Elementary matrix theory

    CERN Document Server

    Eves, Howard

    1980-01-01

    The usefulness of matrix theory as a tool in disciplines ranging from quantum mechanics to psychometrics is widely recognized, and courses in matrix theory are increasingly a standard part of the undergraduate curriculum.This outstanding text offers an unusual introduction to matrix theory at the undergraduate level. Unlike most texts dealing with the topic, which tend to remain on an abstract level, Dr. Eves' book employs a concrete elementary approach, avoiding abstraction until the final chapter. This practical method renders the text especially accessible to students of physics, engineeri

  15. Elementary heat transfer analysis

    CERN Document Server

    Whitaker, Stephen; Hartnett, James P

    1976-01-01

    Elementary Heat Transfer Analysis provides information pertinent to the fundamental aspects of the nature of transient heat conduction. This book presents a thorough understanding of the thermal energy equation and its application to boundary layer flows and confined and unconfined turbulent flows. Organized into nine chapters, this book begins with an overview of the use of heat transfer coefficients in formulating the flux condition at phase interface. This text then explains the specification as well as application of flux boundary conditions. Other chapters consider a derivation of the tra

  16. Assessing Elementary Algebra with STACK

    Science.gov (United States)

    Sangwin, Christopher J.

    2007-01-01

    This paper concerns computer aided assessment (CAA) of mathematics in which a computer algebra system (CAS) is used to help assess students' responses to elementary algebra questions. Using a methodology of documentary analysis, we examine what is taught in elementary algebra. The STACK CAA system, http://www.stack.bham.ac.uk/, which uses the CAS…

  17. Elementary School Philosophy: A Response

    Science.gov (United States)

    Wartenberg, Thomas E.

    2012-01-01

    This article is a response to criticism of my book "Big Ideas for Little Kids." The main topics addressed are: Who is the audience for the book? Can people without formal philosophical training can be good facilitators of elementary school philosophy discussions? Is it important to assess attempts to teach philosophy in elementary school? Should…

  18. Nonlinear PDEs

    OpenAIRE

    2015-01-01

    From the Back Cover: The emphasis throughout the present volume is on the practical application of theoretical mathematical models helping to unravel the underlying mechanisms involved in processes from mathematical physics and biosciences. It has been conceived as a unique collection of abstract methods dealing especially with nonlinear partial differential equations (either stationary or evolutionary) that are applied to understand concrete processes involving some important applications re...

  19. A Model of Contagion through Competition in the Aggressive Behaviors of Elementary School Students.

    Science.gov (United States)

    Warren, Keith; Schoppelrey, Susan; Moberg, D. Paul; McDonald, Marilyn

    2005-01-01

    This article extends the work of Kellam, Ling, Merisca, Brown and Ialongo (1998) by applying a mathematical model of competition between children to peer contagion in the aggressive behaviors of elementary school students. Nonlinearity in the relationship between group aggression and individual aggression at 2-year follow-up is present. Consistent…

  20. A Model of Contagion through Competition in the Aggressive Behaviors of Elementary School Students.

    Science.gov (United States)

    Warren, Keith; Schoppelrey, Susan; Moberg, D. Paul; McDonald, Marilyn

    2005-01-01

    This article extends the work of Kellam, Ling, Merisca, Brown and Ialongo (1998) by applying a mathematical model of competition between children to peer contagion in the aggressive behaviors of elementary school students. Nonlinearity in the relationship between group aggression and individual aggression at 2-year follow-up is present. Consistent…

  1. Nonlinear elliptic equations of the second order

    CERN Document Server

    Han, Qing

    2016-01-01

    Nonlinear elliptic differential equations are a diverse subject with important applications to the physical and social sciences and engineering. They also arise naturally in geometry. In particular, much of the progress in the area in the twentieth century was driven by geometric applications, from the Bernstein problem to the existence of Kähler-Einstein metrics. This book, designed as a textbook, provides a detailed discussion of the Dirichlet problems for quasilinear and fully nonlinear elliptic differential equations of the second order with an emphasis on mean curvature equations and on Monge-Ampère equations. It gives a user-friendly introduction to the theory of nonlinear elliptic equations with special attention given to basic results and the most important techniques. Rather than presenting the topics in their full generality, the book aims at providing self-contained, clear, and "elementary" proofs for results in important special cases. This book will serve as a valuable resource for graduate stu...

  2. Elementary differential geometry

    CERN Document Server

    Pressley, Andrew

    2001-01-01

    Curves and surfaces are objects that everyone can see, and many of the questions that can be asked about them are natural and easily understood Differential geometry is concerned with the precise mathematical formulation of some of these questions, and with trying to answer them using calculus techniques It is a subject that contains some of the most beautiful and profound results in mathematics yet many of these are accessible to higher-level undergraduates Elementary Differential Geometry presents the main results in the differential geometry of curves and surfaces while keeping the prerequisites to an absolute minimum Nothing more than first courses in linear algebra and multivariate calculus are required, and the most direct and straightforward approach is used at all times Numerous diagrams illustrate both the ideas in the text and the examples of curves and surfaces discussed there The book will provide an invaluable resource to all those taking a first course in differential geometry, for their lecture...

  3. Experiences of Redesigning an Elementary Education Program

    Science.gov (United States)

    Chang, Sau Hou

    2016-01-01

    This paper aims to share the experiences of redesigning an elementary education program. Steps of redesigning the elementary education program were enumerated. Challenges in the redesign of the elementary education program were discussed. The new elementary education program was described. Lessons learned from the redesign of the elementary…

  4. Predicting Success in Elementary Algebra

    Science.gov (United States)

    Mogull, R. G.; Rosengarten, W., Jr.

    1974-01-01

    The purpose of this study was to develop a device for predicting student success in a high school Elementary Algebra course. It was intended to assist guidance counselors in advising students in selecting the most appropriate mathematics course. (Editor)

  5. Astronomy in the Elementary Schools.

    Science.gov (United States)

    Gaides, Ed

    1981-01-01

    Presents two sets of astronomy activities for elementary students: (1) constructing scale models of the solar system which depict relative distances and diameters, and (2) demonstrating the effects of factors responsible for the seasons. (WB)

  6. Enhancing pre-service elementary

    Directory of Open Access Journals (Sweden)

    Mehmet AYDENİZ

    2010-03-01

    Full Text Available This study explored the impact of a reflective teaching method on pre-service elementary teachers’ conceptual understanding of the lunar phases, reasons for seasons, and simple electric circuits. Data were collected from 40 pre-service elementary teachers about their conceptual understanding of the lunar phases, reasons for seasons and day and night, and simple electric circuits pre and post instruction. Findings show that the instructional approach adopted by a science teacher educator had a significant impact on pre-serviceelementary school teachers’ conceptual understanding of lunar phases, seasonal changes and simple electric circuits. The discussion focuses on pre-service elementary school teachers’ misconceptions about the lunar phases, seasonal changes and simple electric circuits as revealed through their answers to the pre-test questions. Further discussion focuses on the implications of the findings for pre-service elementary school science teacher education.

  7. Elementary number theory with programming

    CERN Document Server

    Lewinter, Marty

    2015-01-01

    A successful presentation of the fundamental concepts of number theory and computer programming Bridging an existing gap between mathematics and programming, Elementary Number Theory with Programming provides a unique introduction to elementary number theory with fundamental coverage of computer programming. Written by highly-qualified experts in the fields of computer science and mathematics, the book features accessible coverage for readers with various levels of experience and explores number theory in the context of programming without relying on advanced prerequisite knowledge and con

  8. Nonlinear resonances

    CERN Document Server

    Rajasekar, Shanmuganathan

    2016-01-01

    This introductory text presents the basic aspects and most important features of various types of resonances and anti-resonances in dynamical systems. In particular, for each resonance, it covers the theoretical concepts, illustrates them with case studies, and reviews the available information on mechanisms, characterization, numerical simulations, experimental realizations, possible quantum analogues, applications and significant advances made over the years. Resonances are one of the most fundamental phenomena exhibited by nonlinear systems and refer to specific realizations of maximum response of a system due to the ability of that system to store and transfer energy received from an external forcing source. Resonances are of particular importance in physical, engineering and biological systems - they can prove to be advantageous in many applications, while leading to instability and even disasters in others. The book is self-contained, providing the details of mathematical derivations and techniques invo...

  9. Nonlinear Dynamics

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    3.1 A Unified Nonlinear Feedback Functional Method for Study Both Control and Synchronization of Spatiotemporal Chaos Fang Jinqing Ali M. K. (Department of Physics, The University of Lethbridge,Lethbridge, Alberta T1K 3M4,Canada) Two fundamental questions dominate future chaos control theories.The first is the problem of controlling hyperchaos in higher dimensional systems.The second question has yet to be addressed:the problem of controlling spatiotemporal chaos in a spatiotemporal system.In recent years, control and synchronization of spatiotemporal chaos and hyperchaos have became a much more important and challenging subject. The reason for this is the control and synchronism of such behaviours have extensive and great potential of interdisciplinary applications, such as security communication, information processing, medicine and so on. However, this subject is not much known and remains an outstanding open.

  10. Nonlinear photon-assisted tunneling transport in optical gap antennas.

    Science.gov (United States)

    Stolz, Arnaud; Berthelot, Johann; Mennemanteuil, Marie-Maxime; Colas des Francs, Gérard; Markey, Laurent; Meunier, Vincent; Bouhelier, Alexandre

    2014-05-14

    We introduce strongly coupled optical gap antennas to interface optical radiation with current-carrying electrons at the nanoscale. The transducer relies on the nonlinear optical and electrical properties of an optical gap antenna operating in the tunneling regime. We discuss the underlying physical mechanisms controlling the conversion involving d-band electrons and demonstrate that a simple two-wire optical antenna can provide advanced optoelectronic functionalities beyond tailoring the electromagnetic response of a single emitter. Interfacing an electronic command layer with a nanoscale optical device may thus be facilitated by the optical rectennas discussed here.

  11. Nonlinear Materials Characterization Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Nonlinear Materials Characterization Facility conducts photophysical research and development of nonlinear materials operating in the visible spectrum to protect...

  12. Nonlinear singular vectors and nonlinear singular values

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A novel concept of nonlinear singular vector and nonlinear singular value is introduced, which is a natural generalization of the classical linear singular vector and linear singular value to the nonlinear category. The optimization problem related to the determination of nonlinear singular vectors and singular values is formulated. The general idea of this approach is demonstrated by a simple two-dimensional quasigeostrophic model in the atmospheric and oceanic sciences. The advantage and its applications of the new method to the predictability, ensemble forecast and finite-time nonlinear instability are discussed. This paper makes a necessary preparation for further theoretical and numerical investigations.

  13. Nonlinear fitness landscape of a molecular pathway.

    Directory of Open Access Journals (Sweden)

    Lilia Perfeito

    2011-07-01

    Full Text Available Genes are regulated because their expression involves a fitness cost to the organism. The production of proteins by transcription and translation is a well-known cost factor, but the enzymatic activity of the proteins produced can also reduce fitness, depending on the internal state and the environment of the cell. Here, we map the fitness costs of a key metabolic network, the lactose utilization pathway in Escherichia coli. We measure the growth of several regulatory lac operon mutants in different environments inducing expression of the lac genes. We find a strikingly nonlinear fitness landscape, which depends on the production rate and on the activity rate of the lac proteins. A simple fitness model of the lac pathway, based on elementary biophysical processes, predicts the growth rate of all observed strains. The nonlinearity of fitness is explained by a feedback loop: production and activity of the lac proteins reduce growth, but growth also affects the density of these molecules. This nonlinearity has important consequences for molecular function and evolution. It generates a cliff in the fitness landscape, beyond which populations cannot maintain growth. In viable populations, there is an expression barrier of the lac genes, which cannot be exceeded in any stationary growth process. Furthermore, the nonlinearity determines how the fitness of operon mutants depends on the inducer environment. We argue that fitness nonlinearities, expression barriers, and gene-environment interactions are generic features of fitness landscapes for metabolic pathways, and we discuss their implications for the evolution of regulation.

  14. Elementary functions algorithms and implementation

    CERN Document Server

    Muller, Jean-Michel

    2016-01-01

    This textbook presents the concepts and tools necessary to understand, build, and implement algorithms for computing elementary functions (e.g., logarithms, exponentials, and the trigonometric functions). Both hardware- and software-oriented algorithms are included, along with issues related to accurate floating-point implementation. This third edition has been updated and expanded to incorporate the most recent advances in the field, new elementary function algorithms, and function software. After a preliminary chapter that briefly introduces some fundamental concepts of computer arithmetic, such as floating-point arithmetic and redundant number systems, the text is divided into three main parts. Part I considers the computation of elementary functions using algorithms based on polynomial or rational approximations and using table-based methods; the final chapter in this section deals with basic principles of multiple-precision arithmetic. Part II is devoted to a presentation of “shift-and-add” algorithm...

  15. Acoustics in the elementary classroom

    Science.gov (United States)

    Hansen, Uwe J.

    2005-04-01

    The need for increased science exposure at all educational levels continues to be acute. Science is almost universally perceived as difficult, and its ability to raise the quality of life in the presence of apparently insurmountable social problems is increasingly suspect. Over the past 15 years we have conducted teacher workshops, visited classrooms, have organized hands-on demonstration sessions, judged science fairs, and mentored high school students in research efforts, all in an attempt to raise the level of enthusiasm for science. A look ahead suggests that the need continues. Elementary school teachers all too often limit their own science skills to plants and animals, and thus physics concepts do not get the exposure needed to generate the necessary excitement for the physical sciences. Workshops for Elementary grade teachers will be described, which are aimed at preparing teachers to use music as a vehicle to introduce basic physics concepts in the upper elementary grades.

  16. Elementary processes in gas discharges

    CERN Document Server

    Bronold, Franz X

    2008-01-01

    This chapter presents, from a quantum-mechanical point of view, a tutorial discussion of elementary collision processes in the bulk of a gas discharge. Instead of merely listing kitchen-made cross section formulae and unrelated cross section data, emphasis has been given on an unified description of elementary processes based on general principles of quantum-mechanical multi-channel scattering theory. By necessity, the presentation is rather dense. Technical details left out, as well as cross section data, can be found, respectively, in the quoted original papers and the review articles, monographs, and web-sites mentioned in the introductory remarks to this chapter.

  17. Matter and Elementary Particles : Interactions and Qualities

    OpenAIRE

    Bezares Roder, Nils Manuel

    2005-01-01

    The elementary interactions of nature are discussed, based on the structure of the atom. Elementary particles are categorized by their qualities, especially their spin and statistics, but as well charge and compound forms among others. The connection to CP-behaviour and the different elementary interactions are discussed, as well as some open questions and ideas in modern elementary particle physics.The modern physical understanding of matter is reviewed, parting from Quantum Mechanics and Ge...

  18. 2-bit Flip Mutation Elementary Fitness Landscapes

    OpenAIRE

    Langdon, William

    2010-01-01

    Genetic Programming parity is not elementary. GP parity cannot be represented as the sum of a small number of elementary landscapes. Statistics, including fitness distance correlation, of Parity's fitness landscape are calculated. Using Walsh analysis the eigen values and eigenvectors of the Laplacian of the two bit flip fitness landscape are given and a ruggedness measure for elementary landscapes is proposed. An elementary needle in a haystack (NIH) landscape is g...

  19. Nonlinear low-frequency electrostatic wave dynamics in a two-dimensional quantum plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Samiran, E-mail: sran_g@yahoo.com [Department of Applied Mathematics, University of Calcutta, 92, Acharya Prafulla Chandra Road, Kolkata-700 009 (India); Chakrabarti, Nikhil, E-mail: nikhil.chakrabarti@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata-700064 (India)

    2016-08-15

    The problem of two-dimensional arbitrary amplitude low-frequency electrostatic oscillation in a quasi-neutral quantum plasma is solved exactly by elementary means. In such quantum plasmas we have treated electrons quantum mechanically and ions classically. The exact analytical solution of the nonlinear system exhibits the formation of dark and black solitons. Numerical simulation also predicts the possible periodic solution of the nonlinear system. Nonlinear analysis reveals that the system does have a bifurcation at a critical Mach number that depends on the angle of propagation of the wave. The small-amplitude limit leads to the formation of weakly nonlinear Kadomstev–Petviashvili solitons.

  20. Revisiting the Montessori Elementary Biology Sequence.

    Science.gov (United States)

    Scott, Judy; Lanaro, Pamela

    1994-01-01

    Suggests a revised Montessori elementary biology sequence based on the new five-kingdom model. In keeping with Montessori principles that move the learner from the whole to the parts and from the simple to the complex, offers a proposed outline of instruction for the lower elementary (6-9) level and for the upper elementary (9-12) level. (TJQ)

  1. Languages in Elementary Schools. International Education Series.

    Science.gov (United States)

    Muller, Kurt E., Ed.

    Ten essays address aspects of second language instruction at the elementary school level: "Elementary School Foreign Languages: Perspectives, Practices, and Promises" (Carol Ann Pesola, Helena Anderson Curtain); "The Integrated Curriculum: Rethinking the Elementary School Foreign Language Program for the '90s" (Virginia…

  2. NONLINEAR EXPECTATIONS AND NONLINEAR MARKOV CHAINS

    Institute of Scientific and Technical Information of China (English)

    PENG SHIGE

    2005-01-01

    This paper deals with nonlinear expectations. The author obtains a nonlinear generalization of the well-known Kolmogorov's consistent theorem and then use it to construct filtration-consistent nonlinear expectations via nonlinear Markov chains. Compared to the author's previous results, i.e., the theory of g-expectations introduced via BSDE on a probability space, the present framework is not based on a given probability measure. Many fully nonlinear and singular situations are covered. The induced topology is a natural generalization of Lp-norms and L∞-norm in linear situations.The author also obtains the existence and uniqueness result of BSDE under this new framework and develops a nonlinear type of von Neumann-Morgenstern representation theorem to utilities and present dynamic risk measures.

  3. Elementary evolutions in Banach algebra

    OpenAIRE

    Lindsay, J. Martin; Das, Bata Krishna

    2013-01-01

    An elementary class of evolutions in unital Banach algebras is obtained by integrating product functions over Guichardet's symmetric measure space on the half-line. These evolutions, along with a useful subclass, are characterised and a Lie-Trotter product formula is proved. The class is rich enough to form the basis for a recent approach to quantum stochastic evolutions.

  4. Cooperative Learning in Elementary Schools

    Science.gov (United States)

    Slavin, Robert E.

    2015-01-01

    Cooperative learning refers to instructional methods in which students work in small groups to help each other learn. Although cooperative learning methods are used for different age groups, they are particularly popular in elementary (primary) schools. This article discusses methods and theoretical perspectives on cooperative learning for the…

  5. Multicultural Mini-Units. Elementary.

    Science.gov (United States)

    Flora, Sherrill B.

    The teaching mini-units in this teacher's guide are designed for use with elementary level students. Thematic study units are given for each of the following countries or continents: Africa, Australia, Brazil, Canada, China, England, France, Germany, Greece, India, Israel, Italy, Japan, Mexico, Netherlands, Russia, Spain, Sweden, Thailand, and the…

  6. Elementary School Teachers' Manipulative Use

    Science.gov (United States)

    Uribe-Florez, Lida J.; Wilkins, Jesse L. M.

    2010-01-01

    Using data from 503 inservice elementary teachers, this study investigated the relationship between teachers' background characteristics, teachers' beliefs about manipulatives, and the frequency with which teachers use manipulatives as part of their mathematics instruction. Findings from the study show that teachers' grade level and beliefs about…

  7. Elementary Algebra Connections to Precalculus

    Science.gov (United States)

    Lopez-Boada, Roberto; Daire, Sandra Arguelles

    2013-01-01

    This article examines the attitudes of some precalculus students to solve trigonometric and logarithmic equations and systems using the concepts of elementary algebra. With the goal of enticing the students to search for and use connections among mathematical topics, they are asked to solve equations or systems specifically designed to allow…

  8. Assessment in Elementary Dance Education

    Science.gov (United States)

    Englebright, Krissa; Mahoney, Meg Robson

    2012-01-01

    In this article, two public school elementary dance educators share their experiences developing and implementing dance performance assessments. The assessments were developed for the State of Washington Office of the Superintendent of Public Instruction to assess student learning in dance education and bring dance assessment to an equal platform…

  9. Elementary Students' Metaphors for Democracy

    Science.gov (United States)

    Dundar, Hakan

    2012-01-01

    The purpose of the research was to reveal elementary 8th grade students' opinions concerning democracy with the aid of metaphors. The students were asked to produce metaphors about the concept of democracy. 140 students from 3 public schools in Ankara (Turkey) participated in the research. 55% of the students were females and 45% were males. The…

  10. Multicultural Mini-Units. Elementary.

    Science.gov (United States)

    Flora, Sherrill B.

    The teaching mini-units in this teacher's guide are designed for use with elementary level students. Thematic study units are given for each of the following countries or continents: Africa, Australia, Brazil, Canada, China, England, France, Germany, Greece, India, Israel, Italy, Japan, Mexico, Netherlands, Russia, Spain, Sweden, Thailand, and the…

  11. Thomas Edison Accelerated Elementary School.

    Science.gov (United States)

    Levin, Henry M.; Chasin, Gene

    This paper describes early outcomes of a Sacramento, California, elementary school that participated in the Accelerated Schools Project. The school, which serves many minority and poor students, began training for the project in 1992. Accelerated Schools were designed to advance the learning rate of students through a gifted and talented approach,…

  12. Teaching Elementary Students about Japan

    Science.gov (United States)

    Fitzhugh, William P.

    This paper presents a study unit on Japan for elementary students which can be adapted for any level. Lessons include: (1) "Video Traveling Activities To Accompany Students on Their Journey to Japan"; (2) "Travel Brochure"; (3) "Discovering Culture by Using a Realia Kit"; (4) "Comparative Geography Using the Five Fundamental Themes of Geography";…

  13. Electrical elementary diagrams and operators

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, B.K. [Human Factors Practical Inc., Dipper Harbour, New Brunswick (Canada)]. E-mail: HumanFactors@netscape.ca

    2005-07-01

    After 40 years of reading and interrupting electrical elementary logic drawings, I have concluded that we need to make a change. We need to write and express our nuclear power plant logic in some other language than relay ladder logic, solid state logic or computer mnemonics. The language should be English, or your native language, and the format should be Descriptive Block Diagrams. (author)

  14. Digital Photography for Elementary Students

    Science.gov (United States)

    Neckers, Matt

    2009-01-01

    Most elementary students approach photography in an open-minded, experimental way. As a result, their images are often more playful than those taken by adults. Students discover more through their own explorations than they would learn through overly structured lessons. In this article, the author describes how he introduces his elementary…

  15. Digital Photography for Elementary Students

    Science.gov (United States)

    Neckers, Matt

    2009-01-01

    Most elementary students approach photography in an open-minded, experimental way. As a result, their images are often more playful than those taken by adults. Students discover more through their own explorations than they would learn through overly structured lessons. In this article, the author describes how he introduces his elementary…

  16. Franklin Elementary PTA's "Sweet Success"

    Science.gov (United States)

    Freemon, Jennifer

    2012-01-01

    Just a few short years ago, Franklin Elementary in Glendale, California, was in danger of closing its doors because enrollment was so low. The school district decided to put into place a series of language immersion programs at the site. It currently houses Spanish, Italian, and German immersion programs. These programs have boosted Franklin's…

  17. Elementary Students' Metaphors for Democracy

    Science.gov (United States)

    Dundar, Hakan

    2012-01-01

    The purpose of the research was to reveal elementary 8th grade students' opinions concerning democracy with the aid of metaphors. The students were asked to produce metaphors about the concept of democracy. 140 students from 3 public schools in Ankara (Turkey) participated in the research. 55% of the students were females and 45% were males. The…

  18. Elementary Algebra Connections to Precalculus

    Science.gov (United States)

    Lopez-Boada, Roberto; Daire, Sandra Arguelles

    2013-01-01

    This article examines the attitudes of some precalculus students to solve trigonometric and logarithmic equations and systems using the concepts of elementary algebra. With the goal of enticing the students to search for and use connections among mathematical topics, they are asked to solve equations or systems specifically designed to allow…

  19. Assessment in Elementary Dance Education

    Science.gov (United States)

    Englebright, Krissa; Mahoney, Meg Robson

    2012-01-01

    In this article, two public school elementary dance educators share their experiences developing and implementing dance performance assessments. The assessments were developed for the State of Washington Office of the Superintendent of Public Instruction to assess student learning in dance education and bring dance assessment to an equal platform…

  20. Complex dynamics and morphogenesis an introduction to nonlinear science

    CERN Document Server

    Misbah, Chaouqi

    2017-01-01

    This book offers an introduction to the physics of nonlinear phenomena through two complementary approaches: bifurcation theory and catastrophe theory. Readers will be gradually introduced to the language and formalisms of nonlinear sciences, which constitute the framework to describe complex systems. The difficulty with complex systems is that their evolution cannot be fully predicted because of the interdependence and interactions between their different components. Starting with simple examples and working toward an increasing level of universalization, the work explores diverse scenarios of bifurcations and elementary catastrophes which characterize the qualitative behavior of nonlinear systems. The study of temporal evolution is undertaken using the equations that characterize stationary or oscillatory solutions, while spatial analysis introduces the fascinating problem of morphogenesis. Accessible to undergraduate university students in any discipline concerned with nonlinear phenomena (physics, mathema...

  1. Analytical Approximate Solutions for the Cubic-Quintic Duffing Oscillator in Terms of Elementary Functions

    Directory of Open Access Journals (Sweden)

    A. Beléndez

    2012-01-01

    Full Text Available Accurate approximate closed-form solutions for the cubic-quintic Duffing oscillator are obtained in terms of elementary functions. To do this, we use the previous results obtained using a cubication method in which the restoring force is expanded in Chebyshev polynomials and the original nonlinear differential equation is approximated by a cubic Duffing equation. Explicit approximate solutions are then expressed as a function of the complete elliptic integral of the first kind and the Jacobi elliptic function cn. Then we obtain other approximate expressions for these solutions, which are expressed in terms of elementary functions. To do this, the relationship between the complete elliptic integral of the first kind and the arithmetic-geometric mean is used and the rational harmonic balance method is applied to obtain the periodic solution of the original nonlinear oscillator.

  2. Analytical Approximate Solutions for the Cubic-Quintic Duffing Oscillator in Terms of Elementary Functions

    OpenAIRE

    A. Beléndez; ALVAREZ, M. L.; Francés, J.; S. Bleda; Beléndez, T.; Nájera, A.; Arribas, E.

    2012-01-01

    Accurate approximate closed-form solutions for the cubic-quintic Duffing oscillator are obtained in terms of elementary functions. To do this, we use the previous results obtained using a cubication method in which the restoring force is expanded in Chebyshev polynomials and the original nonlinear differential equation is approximated by a cubic Duffing equation. Explicit approximate solutions are then expressed as a function of the complete elliptic integral of the first kind and the Jacobi ...

  3. NEW BIFURCATION PATTERNS IN ELEMENTARY BIFURCATION PROBLEMS WITH SINGLE-SIDE CONSTRAINT

    Institute of Scientific and Technical Information of China (English)

    吴志强; 陈予恕

    2001-01-01

    Bifurcations with constraints are open problems appeared in research on periodic bifurcations of nonlinear dynamical systems, but the present singularity theory doesn't contain any analytical methods and results about it. As the complement to singularity theory and the first step to study on constrained bifurcations, here are given the transition sets and persistent perturbed bifurcation diagrams of 10 elementary bifurcation of codimension no more than three.

  4. Efficent Estimation of the Non-linear Volatility and Growth Model

    OpenAIRE

    2009-01-01

    Ramey and Ramey (1995) introduced a non-linear model relating volatility to growth. The solution of this model by generalised computer algorithms for non-linear maximum likelihood estimation encounters the usual difficulties and is, at best, tedious. We propose an algebraic solution for the model that provides fully efficient estimators and is elementary to implement as a standard ordinary least squares procedure. This eliminates issues such as the ‘guesstimation’ of initial values and mul...

  5. Advances in nonlinear optics

    CERN Document Server

    Chen, Xianfeng; Zeng, Heping; Guo, Qi; She, Weilong

    2015-01-01

    This book presents an overview of the state of the art of nonlinear optics from weak light nonlinear optics, ultrafast nonlinear optics to electro-optical theory and applications. Topics range from the fundamental studies of the interaction between matter and radiation to the development of devices, components, and systems of tremendous commercial interest for widespread applications in optical telecommunications, medicine, and biotechnology.

  6. Distributed nonlinear optical response

    DEFF Research Database (Denmark)

    Nikolov, Nikola Ivanov

    2005-01-01

    The purpose of the research presented here is to investigate basic physical properties in nonlinear optical materials with delayed or nonlocal nonlinearity. Soliton propagation, spectral broadening and the influence of the nonlocality or delay of the nonlinearity are the main focusses in the work...

  7. Noncommutative Nonlinear Supersymmetry

    CERN Document Server

    Nishino, H; Nishino, Hitoshi; Rajpoot, Subhash

    2002-01-01

    We present noncommutative nonlinear supersymmetric theories. The first example is a non-polynomial Akulov-Volkov-type lagrangian with noncommutative nonlinear global supersymmetry in arbitrary space-time dimensions. The second example is the generalization of this lagrangian to Dirac-Born-Infeld lagrangian with nonlinear supersymmetry realized in dimensions D=2,3,4 and 6 (mod 8).

  8. Fiber Nonlinearities: A Tutorial

    Institute of Scientific and Technical Information of China (English)

    Govind P. Agrawal

    2003-01-01

    Fiber nonlinearities have long been regarded as being mostly harmful for fiber-optic communication systems. Over the last few years, however, the nonlinear effects are increasingly being used for practical telecommunications applications,the Raman amplification being only one of the recent examples. In this tutorial I review the vario us nonlinear effects occurring in optical fibers from both standpoints..

  9. Fiber Nonlinearities: A Tutorial

    Institute of Scientific and Technical Information of China (English)

    Govind; P.; Agrawal

    2003-01-01

    Fiber nonlinearities have long been regarded as being mostly harmful for fiber-optic communication systems. Over the last few years, however, the nonlinear effects are increasingly being used for practical telecommunications applications, the Raman amplification being only one of the recent examples. In this tutorial I review the various nonlinear effects occurring in optical fibers from both standpoints..

  10. Elementary Particles A New Approach

    Directory of Open Access Journals (Sweden)

    FranciscoMartnezFlores.

    2015-07-01

    Full Text Available ABSTRACT It is shown the inexistence of neutrinos to define precisely the concept of relativistics mass under this scheme to elementarys particles as electron and interactions particles like photons correspond an electromagnetic and virtual mass. Nucleons protons and neutrons have real or inertial mass for being composite particles since inertia needs structure it is provided by an interactive network originated by strong and weak forces. This mass is building up atoms and all the material world under Classical Physics and Chemistrys laws.These actual masses may be considered as electromagnetic and virtual one thanks to its charge in order to establish the high energies level needed to obtain all particles physics elementary or not which are governed by the laws of Quantum Physics. With all this one may set up amore reasonable and understandable new Standard Model which being projected into Cosmological Model can get rid of some inconsistencies and concepts difficult to be admitted.

  11. PBH tests for nonlinear systems

    NARCIS (Netherlands)

    Kawano, Yu; Ohtsuka, Toshiyuki

    2017-01-01

    Recently, concepts of nonlinear eigenvalues and eigenvectors are introduced. In this paper, we establish connections between the nonlinear eigenvalues and nonlinear accessibility/observability. In particular, we provide a generalization of Popov- Belevitch-Hautus (PBH) test to nonlinear accessibilit

  12. Supersymmetry in Elementary Particle Physics

    OpenAIRE

    Peskin, Michael E.

    2008-01-01

    These lectures, presented at the 2006 TASI summer school, give a general introduction to supersymmetry, emphasizing its application to models of elementary particle physics at the 100 GeV energy scale. I discuss the following topics: the construction of supersymmetric Lagrangians with scalars, fermions, and gauge bosons, the structure and mass spectrum of the Minimal Supersymmetric Standard Model (MSSM), the measurement of the parameters of the MSSM at high-energy colliders, and the solutions...

  13. Supersymmetry in Elementary Particle Physics

    Energy Technology Data Exchange (ETDEWEB)

    Peskin, Michael E.; /SLAC

    2008-02-05

    These lectures give a general introduction to supersymmetry, emphasizing its application to models of elementary particle physics at the 100 GeV energy scale. I discuss the following topics: the construction of supersymmetric Lagrangians with scalars, fermions, and gauge bosons, the structure and mass spectrum of the Minimal Supersymmetric Standard Model (MSSM), the measurement of the parameters of the MSSM at high-energy colliders, and the solutions that the MSSM gives to the problems of electroweak symmetry breaking and dark matter.

  14. Are Black Holes Elementary Particles?

    CERN Document Server

    Ha, Yuan K

    2009-01-01

    Quantum black holes are the smallest and heaviest conceivable elementary particles. They have a microscopic size but a macroscopic mass. Several fundamental types have been constructed with some remarkable properties. Quantum black holes in the neighborhood of the Galaxy could resolve the paradox of ultra-high energy cosmic rays detected in Earth's atmosphere. They may also play a role as dark matter in cosmology.

  15. Nonlinear dynamics and complexity

    CERN Document Server

    Luo, Albert; Fu, Xilin

    2014-01-01

    This important collection presents recent advances in nonlinear dynamics including analytical solutions, chaos in Hamiltonian systems, time-delay, uncertainty, and bio-network dynamics. Nonlinear Dynamics and Complexity equips readers to appreciate this increasingly main-stream approach to understanding complex phenomena in nonlinear systems as they are examined in a broad array of disciplines. The book facilitates a better understanding of the mechanisms and phenomena in nonlinear dynamics and develops the corresponding mathematical theory to apply nonlinear design to practical engineering.

  16. Experimental Investigation on Ice-Coating and Ice-Melting of Large-Section Current Carrying Conductors for UHVDC Transmission Project%特高压直流输电大截面导线带电覆冰与融冰特性试验研究

    Institute of Scientific and Technical Information of China (English)

    陆佳政; 胡建平; 方针

    2013-01-01

      现有小截面导线覆冰和融冰规律不能直接线性换算至大截面导线,为此在人工气候实验室开展 LGJ-720/50和JL/G3A-900/40这2种特高压直流输电大截面导线的带电覆冰与融冰试验,分析覆冰厚度增长与电流和气象参数的变化规律,得到大截面导线融冰时间与融冰电流、环境温度和风速、覆冰厚度的特性曲线。研究结果表明运行电流通过产生焦耳热降低水滴在大截面导线上的冻结系数能抑制覆冰增长;风速增大、降雨量增加可以增大水滴的碰撞系数和收集系数,温度降低可增大冻结系数,从而加快导线覆冰增长速度;环境温度还决定着导线覆冰类型。大截面导线融冰时间主要取决于导线表面需要融化的冰层厚度,并随着融冰电流的增大逐渐减小;环境温度越低,风速越大,融冰时间越长;融冰时间随覆冰厚度增加呈线性规律增长。研究结果能够为特高压直流输电线路阻冰和融冰提供理论指导。%  Existing law of ice-coating and ice-melting rules for small-sectional conductors cannot be directly applied to large-sectional conductors by linear conversion, consequently the ice-coating and ice-melting experiments for two kinds of large-sectional current-carrying conductors of UHVDC transmission project, namely LGJ-720/50 and JL/G3A-900/40, were carried out in artificial climate laboratory to analyze the rule among the growth of thickness of ice-coating, current-carrying capacity of the conductors and meteorological parameters, and characteristic curves between ice-melting time of large-sectional conductor and ice-melting current, ambient temperature, wind speed and thickness of ice-coating were obtained. Investigation results show that the increase of ice-coating thickness can be restrained through decreasing freezing coefficient of water droplets on large-sectional conductor by Joule heat arising from running current

  17. Nonlinear Elliptic Differential Equations with Multivalued Nonlinearities

    Indian Academy of Sciences (India)

    Antonella Fiacca; Nikolaos Matzakos; Nikolaos S Papageorgiou; Raffaella Servadei

    2001-11-01

    In this paper we study nonlinear elliptic boundary value problems with monotone and nonmonotone multivalued nonlinearities. First we consider the case of monotone nonlinearities. In the first result we assume that the multivalued nonlinearity is defined on all $\\mathbb{R}$. Assuming the existence of an upper and of a lower solution, we prove the existence of a solution between them. Also for a special version of the problem, we prove the existence of extremal solutions in the order interval formed by the upper and lower solutions. Then we drop the requirement that the monotone nonlinearity is defined on all of $\\mathbb{R}$. This case is important because it covers variational inequalities. Using the theory of operators of monotone type we show that the problem has a solution. Finally in the last part we consider an eigenvalue problem with a nonmonotone multivalued nonlinearity. Using the critical point theory for nonsmooth locally Lipschitz functionals we prove the existence of at least two nontrivial solutions (multiplicity theorem).

  18. Elementary Continuum Mechanics for Everyone

    DEFF Research Database (Denmark)

    Byskov, Esben

    •The principle of virtual work is used to establish consistent theories of kinematic nonlinearity and linearity for other kinds of bodies, such as beams and plates •An in-depth treatment of structural instability as many structures fail due to this phenomenon •An introduction to the most versatile...... numerical method, the finite element method, including means of mending inherent problems •An informal, yet precise exposition that emphasizes not just how a topic is treated, but discusses why a particular choice is made The book opens with a derivation of kinematically nonlinear 3-D continuum mechanics...... for solids. Then the principle of virtual work is utilized to derive the simpler, kinematically linear 3-D theory and to provide the foundation for developing consistent theories of kinematic nonlinearity and linearity for specialized continua, such as beams and plates, and finite element methods...

  19. Scalar spin of elementary fermions

    Energy Technology Data Exchange (ETDEWEB)

    Jourjine, A., E-mail: jourjine@pks.mpg.de

    2014-01-20

    We show that, using the experimentally observed values of CKM and PMNS mixing matrices, all known elementary fermions can be assigned a new quantum number, the scalar spin, in a unique way. This is achieved without introduction of new degrees of freedom. The assignment implies that tau-neutrino should be an anti-Dirac spinor, while mu–tau leptons and charm–top, strange–bottom quarks form Dirac–anti-Dirac scalar spin doublets. The electron and its neutrino remain as originally described by Dirac.

  20. Elementary linear programming with applications

    CERN Document Server

    Kolman, Bernard

    1995-01-01

    Linear programming finds the least expensive way to meet given needs with available resources. Its results are used in every area of engineering and commerce: agriculture, oil refining, banking, and air transport. Authors Kolman and Beck present the basic notions of linear programming and illustrate how they are used to solve important common problems. The software on the included disk leads students step-by-step through the calculations. The Second Edition is completely revised and provides additional review material on linear algebra as well as complete coverage of elementary linear program

  1. The most elementary Bell inequalities

    CERN Document Server

    Sadiq, Muhamad; Bourennane, Mohamed; Cabello, Adan

    2011-01-01

    Every nontrivial Bell inequality can be associated to a graph with some special properties. The simplest of these graphs is the pentagon. In this sense, any Bell inequality associated to a pentagon can be regarded as elementary. We show that there are three of them: one is a primitive Bell inequality inside the Clauser-Horne-Shimony-Holt inequality and, surprisingly, it is not maximally violated by maximally entangled states. The other two are maximally violated by maximally entangled states and are related to the Clauser-Horne inequality and the I3322 inequality, respectively. We report experimental violations of the three inequalities with pairs of photons entangled in polarization.

  2. Nonlinear Dirac Equations

    Directory of Open Access Journals (Sweden)

    Wei Khim Ng

    2009-02-01

    Full Text Available We construct nonlinear extensions of Dirac's relativistic electron equation that preserve its other desirable properties such as locality, separability, conservation of probability and Poincaré invariance. We determine the constraints that the nonlinear term must obey and classify the resultant non-polynomial nonlinearities in a double expansion in the degree of nonlinearity and number of derivatives. We give explicit examples of such nonlinear equations, studying their discrete symmetries and other properties. Motivated by some previously suggested applications we then consider nonlinear terms that simultaneously violate Lorentz covariance and again study various explicit examples. We contrast our equations and construction procedure with others in the literature and also show that our equations are not gauge equivalent to the linear Dirac equation. Finally we outline various physical applications for these equations.

  3. Nonlinear Cross Gramians

    Science.gov (United States)

    Ionescu, Tudor C.; Scherpen, Jacquelien M. A.

    We study the notion of cross Gramians for nonlinear gradient systems, using the characterization in terms of prolongation and gradient extension associated to the system. The cross Gramian is given for the variational system associated to the original nonlinear gradient system. We obtain linearization results that correspond to the notion of a cross Gramian for symmetric linear systems. Furthermore, first steps towards relations with the singular value functions of the nonlinear Hankel operator are studied and yield promising results.

  4. Nonlinear functional analysis

    Directory of Open Access Journals (Sweden)

    W. L. Fouché

    1983-03-01

    Full Text Available In this article we discuss some aspects of nonlinear functional analysis. It included reviews of Banach’s contraction theorem, Schauder’s fixed point theorem, globalising techniques and applications of homotopy theory to nonlinear functional analysis. The author emphasises that fundamentally new ideas are required in order to achieve a better understanding of phenomena which contain both nonlinear and definite infinite dimensional features.

  5. Nonlinear Electrodynamics and QED

    OpenAIRE

    2003-01-01

    The limits of linear electrodynamics are reviewed, and possible directions of nonlinear extension are explored. The central theme is that the qualitative character of the empirical successes of quantum electrodynamics must be used as a guide for understanding the nature of the nonlinearity of electrodynamics at the subatomic level. Some established theories of nonlinear electrodynamics, namely, those of Mie, Born, and Infeld are presented in the language of the modern geometrical and topologi...

  6. Elementary particle physics at the University of Florida

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-01

    This report discusses research in the following areas: theoretical elementary particle physics; experimental elementary particle physics; axion project; SSC detector development; and computer acquisition. (LSP).

  7. Nonlinear Physics of Plasmas

    CERN Document Server

    Kono, Mitsuo

    2010-01-01

    A nonlinearity is one of the most important notions in modern physics. A plasma is rich in nonlinearities and provides a variety of behaviors inherent to instabilities, coherent wave structures and turbulence. The book covers the basic concepts and mathematical methods, necessary to comprehend nonlinear problems widely encountered in contemporary plasmas, but also in other fields of physics and current research on self-organized structures and magnetized plasma turbulence. The analyses make use of strongly nonlinear models solved by analytical techniques backed by extensive simulations and available experiments. The text is written for senior undergraduates, graduate students, lecturers and researchers in laboratory, space and fusion plasmas.

  8. Nonlinear magnetic metamaterials.

    Science.gov (United States)

    Shadrivov, Ilya V; Kozyrev, Alexander B; van der Weide, Daniel W; Kivshar, Yuri S

    2008-12-08

    We study experimentally nonlinear tunable magnetic metamaterials operating at microwave frequencies. We fabricate the nonlinear metamaterial composed of double split-ring resonators where a varactor diode is introduced into each resonator so that the magnetic resonance can be tuned dynamically by varying the input power. We demonstrate that at higher powers the transmission of the metamaterial becomes power-dependent and, as a result, such metamaterial can demonstrate various nonlinear properties. In particular, we study experimentally the power-dependent shift of the transmission band and demonstrate nonlinearity-induced enhancement (or suppression) of wave transmission. (c) 2008 Optical Society of America

  9. Organic nonlinear optical materials

    Science.gov (United States)

    Umegaki, S.

    1987-01-01

    Recently, it became clear that organic compounds with delocalized pi electrons show a great nonlinear optical response. Especially, secondary nonlinear optical constants of more than 2 digits were often seen in the molecular level compared to the existing inorganic crystals such as LiNbO3. The crystallization was continuously tried. Organic nonlinear optical crystals have a new future as materials for use in the applied physics such as photomodulation, optical frequency transformation, opto-bistabilization, and phase conjugation optics. Organic nonlinear optical materials, e.g., urea, O2NC6H4NH2, I, II, are reviewed with 50 references.

  10. Nonlinearity-reduced interferometer

    Science.gov (United States)

    Wu, Chien-ming

    2007-12-01

    Periodic nonlinearity is a systematic error limiting the accuracy of displacement measurements at the nanometer level. It results from many causes such as the frequency mixing, polarization mixing, polarization-frequency mixing, and the ghost reflections. An interferometer having accuracy in displacement measurement of less than one-nanometer is necessary in nanometrology. To meet the requirement, the periodic nonlinearity should be less than deep sub-nanometer. In this paper, a nonlinearity-reduced interferometry has been proposed. Both the linear- and straightness-interferometer were tested. The developed interferometer demonstrated of a residual nonlinearity less than 25 pm.

  11. Reading Disability and the Elementary School Counselor.

    Science.gov (United States)

    Martinez, David H.; Phelps, R. Neal

    1980-01-01

    Provides the elementary school counselor with a knowledge base in the reading and reading disability areas. The discussion on reading highlights four major areas with which the elementary school counselor should be familiar: definition of reading, proliferation of terms, reading skills assessment, and reading disability. (Author)

  12. Assessment, Autonomy, and Elementary Social Studies Time

    Science.gov (United States)

    Fitchett, Paul G.; Heafner, Tina L.; Lambert, Richard

    2014-01-01

    Background/context: In an era of accountability and standardization, elementary social studies is consistently losing its curricular foothold to English/language arts, math, and science instruction. Purpose: This article examines the relationship between elementary teachers' perceptions of instructional autonomy, teaching context, state testing…

  13. Career Paths of Female Elementary Assistant Principals

    Science.gov (United States)

    Baier, Hope C.

    2013-01-01

    The purpose of this research was to explore the worklife experiences and personal issues of female elementary assistant principals and examine the influence of these factors on their intent to remain in their position or leave. The worklife experiences and perceptions of female elementary assistant principals were categorized as institutional or…

  14. Applying Disciplinary Literacy in Elementary Geography

    Science.gov (United States)

    Britt, Judy; Ming, Kavin

    2017-01-01

    In this article, a social studies teacher and a literacy teacher describe a vision for social studies that highlights reading practices that foster disciplinary literacy in elementary geography. Their purpose is to share a practical approach for enriching elementary social studies lessons and activities with a geographic lens. During the…

  15. Preservice Elementary Teachers' Images of Inventors

    Science.gov (United States)

    Rule, Audrey C.; Bisbo, Erica Lyn; Waloven, Valerie

    2008-01-01

    Technology and invention are an integral part of the elementary school science curriculum, addressed by national standards. Student drawings of scientists have been studied extensively, but little is known of student mental conceptions and drawings of inventors. To uncover student's images of inventors, ninety preservice elementary teachers at a…

  16. Techniques for Vocabulary Teaching in Elementary English

    Institute of Scientific and Technical Information of China (English)

    刘丽华

    2004-01-01

    All teachers know very well how important vocabulary is in learning language, but, for many years, vocabulary has all been neglected in language teaching. In this essay will try to introduce some practical and effective methods in presenting, practising,and consolidating vocabulary in elementary level in which, I wish, the elementary teachers may get some inspiration for their vocabulary teaching.

  17. Self-Efficacy, Taiwan Elementary Teachers Perspective

    Science.gov (United States)

    Jack, Brady M.; Liu, Chia-Ju; Chiu, Hoan-Lin

    2005-01-01

    This paper presents the results of a case study involving Taiwanese elementary teachers who teach science at the elementary grade school level. It advocates the position that a teacher's personal science efficacy belief influences his or her science teaching outcome expectations. It promotes the position that the success Taiwan has experienced in…

  18. Student Leadership Education in Elementary Classrooms

    Science.gov (United States)

    Hess, Lindsay

    2010-01-01

    As I began my career as a teacher, I assumed leadership education would naturally be integrated into the elementary classroom curriculum because I was intrigued by this topic. However, as I spent more time in the classroom I quickly realized leadership skills were not part of regular classroom learning or practice for elementary age students. I…

  19. Introducing Technology Education at the Elementary Level

    Science.gov (United States)

    McKnight, Sean

    2012-01-01

    Many school districts are seeing a need to introduce technology education to students at the elementary level. Pennsylvania's Penn Manor School District is one of them. Pennsylvania has updated science and technology standards for grades 3-8, and after several conversations the author had with elementary principals and the assistant superintendent…

  20. Elementary Principals' Role in Science Instruction

    Science.gov (United States)

    Casey, Patricia; Dunlap, Karen; Brown, Kristen; Davison, Michele

    2012-01-01

    This study explores the role elementary school principals play in science education. Specifically, the study employed an online survey of 16 elementary school principals at high-performing campuses in North Texas to explore their perceptions of how they influenced science education on their campuses. The survey used a combination of Likert-type…

  1. Vacuum alignment with and without elementary scalars

    DEFF Research Database (Denmark)

    Alanne, Tommi; Gertov, Helene; Meroni, Aurora

    2016-01-01

    We systematically elucidate differences and similarities of the vacuum alignment issue in composite and renormalizable elementary extensions of the Standard Model featuring a pseudo-Goldstone Higgs. We also provide general conditions for the stability of the vacuum in the elementary framework......, thereby extending previous studies of the vacuum alignment....

  2. Vacuum alignment with and without elementary scalars

    DEFF Research Database (Denmark)

    Alanne, Tommi; Gertov, Helene; Meroni, Aurora;

    2016-01-01

    We systematically elucidate differences and similarities of the vacuum alignment issue in composite and renormalizable elementary extensions of the Standard Model featuring a pseudo-Goldstone Higgs. We also provide general conditions for the stability of the vacuum in the elementary framework......, thereby extending previous studies of the vacuum alignment....

  3. Vacuum alignment with(out) elementary scalars

    CERN Document Server

    Alanne, Tommi; Meroni, Aurora; Sannino, Francesco

    2016-01-01

    We systematically elucidate differences and similarities of the vacuum alignment issue in composite and renormalizable elementary extensions of the Standard Model featuring a pseudo-Goldstone Higgs. We also provide general conditions for the stability of the vacuum in the elementary framework, thereby extending previous studies of the vacuum alignment.

  4. Elementary lesions in dermatological semiology: literature review.

    Science.gov (United States)

    Cardili, Renata Nahas; Roselino, Ana Maria

    2016-01-01

    Discrepancies in the terminology of elementary lesions persist when texts from Dermatology and Semiology books are compared, which can cause some confusion in both the teaching of undergraduate medical students and the learning acquired by professionals in the field. This review aims to compare and clarify the differences in the description of elementary lesions by many authors, used as references for specialists in dermatology.

  5. Preventing Substance Abuse: An Elementary School Guide.

    Science.gov (United States)

    Alsup, Ben; Boundy, Donna; Brown, Jordan; Reisman, David; Rothbart, Betty

    This booklet is designed to be used by teachers in elementary schools with the Public Broadcasting Systems series "Moyers on Addiction: Close to Home." The series explores the science, treatment, prevention, and politics of addiction. This booklet discusses strategies for preventing substance abuse in elementary school. Also examined are…

  6. Elementary Reading Guide, Level 1-6.

    Science.gov (United States)

    Caverna Independent School District, Horse Cave, KY.

    This elementary reading curriculum guide is designed to provide a well-rounded program of reading instruction and includes the following components: a philosophy of elementary education, behavioral objectives, and characteristics of children of age 5 through age 15. The bulk of the document consists of plans which describe appropriate activities…

  7. Explorations in Elementary Mathematical Modeling

    Directory of Open Access Journals (Sweden)

    Mazen Shahin

    2010-06-01

    Full Text Available In this paper we will present the methodology and pedagogy of Elementary Mathematical Modeling as a one-semester course in the liberal arts core. We will focus on the elementary models in finance and business. The main mathematical tools in this course are the difference equations and matrix algebra. We also integrate computer technology and cooperative learning into this inquiry-based learning course where students work in small groups on carefully designed activities and utilize available software to support problem solving and understanding of real life situations. We emphasize the use of graphical and numerical techniques, rather than theoretical techniques, to investigate and analyze the behavior of the solutions of the difference equations.As an illustration of our approach, we will show a nontraditional and efficient way of introducing models from finance and economics. We will also present an interesting model of supply and demand with a lag time, which is called the cobweb theorem in economics. We introduce a sample of a research project on a technique of removing chaotic behavior from a chaotic system.

  8. Lasers for nonlinear microscopy.

    Science.gov (United States)

    Wise, Frank

    2013-03-01

    Various versions of nonlinear microscopy are revolutionizing the life sciences, almost all of which are made possible because of the development of ultrafast lasers. In this article, the main properties and technical features of short-pulse lasers used in nonlinear microscopy are summarized. Recent research results on fiber lasers that will impact future instruments are also discussed.

  9. Nonlinear optical materials.

    Science.gov (United States)

    Eaton, D F

    1991-07-19

    The current state of materials development in nonlinear optics is summarized, and the promise of these materials is critically evaluated. Properties and important materials constants of current commercial materials and of new, promising, inorganic and organic molecular and polymeric materials with potential in second- and third-order nonlinear optical applications are presented.

  10. Estimating nonlinear models

    Science.gov (United States)

    Billings, S. A.

    1988-03-01

    Time and frequency domain identification methods for nonlinear systems are reviewed. Parametric methods, prediction error methods, structure detection, model validation, and experiment design are discussed. Identification of a liquid level system, a heat exchanger, and a turbocharge automotive diesel engine are illustrated. Rational models are introduced. Spectral analysis for nonlinear systems is treated. Recursive estimation is mentioned.

  11. Nonlinear Cross Gramians

    NARCIS (Netherlands)

    Ionescu, T. C.; Scherpen, J. M. A.; Korytowski, A; Malanowski, K; Mitkowski, W; Szymkat, M

    2009-01-01

    We study the notion of cross Gramians for nonlinear gradient systems, using the characterization in terms of prolongation and gradient extension associated to the system. The cross Gramian is given for the variational system associated to the original nonlinear gradient system. We obtain

  12. Engineered nonlinear lattices

    DEFF Research Database (Denmark)

    Clausen, Carl A. Balslev; Christiansen, Peter Leth; Torner, L.

    1999-01-01

    We show that with the quasi-phase-matching technique it is possible to fabricate stripes of nonlinearity that trap and guide light like waveguides. We investigate an array of such stripes and find that when the stripes are sufficiently narrow, the beam dynamics is governed by a quadratic nonlinear...

  13. Controllability in nonlinear systems

    Science.gov (United States)

    Hirschorn, R. M.

    1975-01-01

    An explicit expression for the reachable set is obtained for a class of nonlinear systems. This class is described by a chain condition on the Lie algebra of vector fields associated with each nonlinear system. These ideas are used to obtain a generalization of a controllability result for linear systems in the case where multiplicative controls are present.

  14. Nonlinear Maneuver Autopilot

    Science.gov (United States)

    Menon, P. K. A.; Badgett, M. E.; Walker, R. A.

    1992-01-01

    Trajectory-control laws based on singular-perturbation theory and nonlinear dynamical modeling. Nonlinear maneuver autopilot commands flight-test trajectories of F-15 airplane. Underlying theory of controller enables separation of variables processed in fast and slow control loops, reducing amount of computation required.

  15. Nonlinear Deep Kernel Learning for Image Annotation.

    Science.gov (United States)

    Jiu, Mingyuan; Sahbi, Hichem

    2017-02-08

    Multiple kernel learning (MKL) is a widely used technique for kernel design. Its principle consists in learning, for a given support vector classifier, the most suitable convex (or sparse) linear combination of standard elementary kernels. However, these combinations are shallow and often powerless to capture the actual similarity between highly semantic data, especially for challenging classification tasks such as image annotation. In this paper, we redefine multiple kernels using deep multi-layer networks. In this new contribution, a deep multiple kernel is recursively defined as a multi-layered combination of nonlinear activation functions, each one involves a combination of several elementary or intermediate kernels, and results into a positive semi-definite deep kernel. We propose four different frameworks in order to learn the weights of these networks: supervised, unsupervised, kernel-based semisupervised and Laplacian-based semi-supervised. When plugged into support vector machines (SVMs), the resulting deep kernel networks show clear gain, compared to several shallow kernels for the task of image annotation. Extensive experiments and analysis on the challenging ImageCLEF photo annotation benchmark, the COREL5k database and the Banana dataset validate the effectiveness of the proposed method.

  16. Nonlinear optics and photonics

    CERN Document Server

    He, Guang S

    2015-01-01

    This book provides a comprehensive presentation on most of the major topics in nonlinear optics and photonics, with equal emphasis on principles, experiments, techniques, and applications. It covers many major new topics including optical solitons, multi-photon effects, nonlinear photoelectric effects, fast and slow light , and Terahertz photonics. Chapters 1-10 present the fundamentals of modern nonlinear optics, and could be used as a textbook with problems provided at the end of each chapter. Chapters 11-17 cover the more advanced topics of techniques and applications of nonlinear optics and photonics, serving as a highly informative reference for researchers and experts working in related areas. There are also 16 pages of color photographs to illustrate the visual appearances of some typical nonlinear optical effects and phenomena. The book could be adopted as a textbook for both undergraduates and graduate students, and serve as a useful reference work for researchers and experts in the fields of physics...

  17. Nonlinear optical systems

    CERN Document Server

    Lugiato, Luigi; Brambilla, Massimo

    2015-01-01

    Guiding graduate students and researchers through the complex world of laser physics and nonlinear optics, this book provides an in-depth exploration of the dynamics of lasers and other relevant optical systems, under the umbrella of a unitary spatio-temporal vision. Adopting a balanced approach, the book covers traditional as well as special topics in laser physics, quantum electronics and nonlinear optics, treating them from the viewpoint of nonlinear dynamical systems. These include laser emission, frequency generation, solitons, optically bistable systems, pulsations and chaos and optical pattern formation. It also provides a coherent and up-to-date treatment of the hierarchy of nonlinear optical models and of the rich variety of phenomena they describe, helping readers to understand the limits of validity of each model and the connections among the phenomena. It is ideal for graduate students and researchers in nonlinear optics, quantum electronics, laser physics and photonics.

  18. Some Elementary Aspects of Means

    Directory of Open Access Journals (Sweden)

    Mowaffaq Hajja

    2013-01-01

    Full Text Available We raise several elementary questions pertaining to various aspects of means. These questions refer to both known and newly introduced families of means, and include questions of characterizations of certain families, relations among certain families, comparability among the members of certain families, and concordance of certain sequences of means. They also include questions about internality tests for certain mean-looking functions and about certain triangle centers viewed as means of the vertices. The questions are accessible to people with no background in means, and it is also expected that these people can seriously investigate, and contribute to the solutions of, these problems. The solutions are expected to require no more than simple tools from analysis, algebra, functional equations, and geometry.

  19. An excursion through elementary mathematics

    CERN Document Server

    Caminha Muniz Neto, Antonio

    2017-01-01

    This book provides a comprehensive, in-depth overview of elementary mathematics as explored in Mathematical Olympiads around the world. It expands on topics usually encountered in high school and could even be used as preparation for a first-semester undergraduate course. This first volume covers Real Numbers, Functions, Real Analysis, Systems of Equations, Limits and Derivatives, and much more. As part of a collection, the book differs from other publications in this field by not being a mere selection of questions or a set of tips and tricks that applies to specific problems. It starts from the most basic theoretical principles, without being either too general or too axiomatic. Examples and problems are discussed only if they are helpful as applications of the theory. Propositions are proved in detail and subsequently applied to Olympic problems or to other problems at the Olympic level. The book also explores some of the hardest problems presented at National and International Mathematics Olympiads, as we...

  20. Light in elementary biological reactions

    Science.gov (United States)

    Sundström, Villy

    2000-09-01

    Light plays an important role in biology. In this review we discuss several processes and systems where light triggers a biological response, i.e. photosynthesis, vision, photoreceptors. For these functions Nature has chosen simple elementary chemical reactions, which occur in highly specialized and organized structures. The high efficiency and specificity of these reactions make them interesting for applications in light energy conversion and opto-electronics. In order to emphasize the synergism in studies of natural and synthetic systems we will discuss a few of each kind, with similar functions. In all cases light triggers a rapid sequence of events, which makes ultrafast spectroscopy an ideal tool to disentangle reaction mechanisms and dynamics.

  1. On the invertibility of elementary operators

    OpenAIRE

    Boudi, Nadia; Bračič, Janko

    2013-01-01

    Let $\\mathscr{X}$ be a complex Banach space and $\\mathcal{L}(\\mathscr{X})$ be the algebra of all bounded linear operators on $\\mathscr{X}$. For a given elementary operator $\\Phi$ of length $2$ on $\\mathcal{L}(\\mathscr{X})$, we determine necessary and sufficient conditions for the existence of a solution of the equation ${\\rm X} \\Phi=0$ in the algebra of all elementary operators on $\\mathcal{L}(\\mathscr{X})$. Our approach allows us to characterize some invertible elementary operators of length...

  2. Nonlinear cochlear mechanics.

    Science.gov (United States)

    Zweig, George

    2016-05-01

    An earlier paper characterizing the linear mechanical response of the organ of Corti [J. Acoust. Soc. Am. 138, 1102-1121 (2015)] is extended to the nonlinear domain. Assuming the existence of nonlinear oscillators nonlocally coupled through the pressure they help create, the oscillator equations are derived and examined when the stimuli are modulated tones and clicks. The nonlinearities are constrained by the requirements of oscillator stability and the invariance of zero crossings in the click response to changes in click amplitude. The nonlinear oscillator equations for tones are solved in terms of the fluid pressure that drives them, and its time derivative, presumably a proxy for forces created by outer hair cells. The pressure equation is reduced to quadrature, the integrand depending on the oscillators' responses. The resulting nonlocally coupled nonlinear equations for the pressure, and oscillator amplitudes and phases, are solved numerically in terms of the fluid pressure at the stapes. Methods for determining the nonlinear damping directly from measurements are described. Once the oscillators have been characterized from their tone and click responses, the mechanical response of the cochlea to natural sounds may be computed numerically. Signal processing inspired by cochlear mechanics opens up a new area of nonlocal nonlinear time-frequency analysis.

  3. Integrable discretisations for a class of nonlinear Schrödinger equations on Grassmann algebras

    Science.gov (United States)

    Grahovski, Georgi G.; Mikhailov, Alexander V.

    2013-12-01

    Integrable discretisations for a class of coupled (super) nonlinear Schrödinger (NLS) type of equations are presented. The class corresponds to a Lax operator with entries in a Grassmann algebra. Elementary Darboux transformations are constructed. As a result, Grassmann generalisations of the Toda lattice and the NLS dressing chain are obtained. The compatibility (Bianchi commutativity) of these Darboux transformations leads to integrable Grassmann generalisations of the difference Toda and NLS equations. The resulting systems will have discrete Lax representations provided by the set of two consistent elementary Darboux transformations. For the two discrete systems obtained, initial value and initial-boundary problems are formulated.

  4. Nonlinear vortex-phonon interactions in a Bose-Einstein condensate

    Science.gov (United States)

    Mendonça, J. T.; Haas, F.; Gammal, A.

    2016-07-01

    We consider the nonlinear coupling between an exact vortex solution in a Bose-Einstein condensate and a spectrum of elementary excitations in the medium. These excitations, or Bogoliubov-de Gennes modes, are indeed a special kind of phonons. We treat the spectrum of elementary excitations in the medium as a gas of quantum particles, sometimes also called bogolons. An exact kinetic equation for the bogolon gas is derived, and an approximate form of this equation, valid in the quasi-classical limit, is also obtained. We study the energy transfer between the vortex and the bogolon gas, and establish conditions for vortex instability and damping.

  5. Nonlinear fiber optics

    CERN Document Server

    Agrawal, Govind P

    2001-01-01

    The Optical Society of America (OSA) and SPIE - The International Society for Optical Engineering have awarded Govind Agrawal with an honorable mention for the Joseph W. Goodman Book Writing Award for his work on Nonlinear Fiber Optics, 3rd edition.Nonlinear Fiber Optics, 3rd Edition, provides a comprehensive and up-to-date account of the nonlinear phenomena occurring inside optical fibers. It retains most of the material that appeared in the first edition, with the exception of Chapter 6, which is now devoted to the polarization effects relevant for light propagation in optical

  6. Will Nonlinear Backcalculation Help?

    DEFF Research Database (Denmark)

    Ullidtz, Per

    2000-01-01

    demonstrates, that treating the subgrade as a nonlinear elastic material, can result in more realistic moduli and a much better agreement between measured and calculated stresses and strains.The response of nonlinear elastic materials can be calculated using the Finite Element Method (FEM). A much simpler...... approach is to use the Method of Equivalent Thicknesses (MET), modified for a nonlinear subgrade. The paper includes an example where moduli backcalculated using FEM, linear elastic theory and MET are compared. Stresses and strains predicted by the three methods are also compared to measured values...

  7. Nonlinear graphene metamaterial

    CERN Document Server

    Nikolaenko, Andrey E; Atmatzakis, Evangelos; Luo, Zhiqiang; Shen, Ze Xiang; De Angelis, Francesco; Boden, Stuart A; Di Fabrizio, Enzo; Zheludev, Nikolay I

    2012-01-01

    We demonstrate that the broadband nonlinear optical response of graphene can be resonantly enhanced by more than an order of magnitude through hybridization with a plasmonic metamaterial,while retaining an ultrafast nonlinear response time of ~1 ps. Transmission modulation close to ~1% is seen at a pump uence of ~0.03 mJ/cm^2 at the wavelength of ~1600 nm. This approach allows to engineer and enhance graphene's nonlinearity within a broad wavelength range enabling applications in optical switching, mode-locking and pulse shaping.

  8. A research Program in Elementary Particle Physics

    Energy Technology Data Exchange (ETDEWEB)

    Sobel, Henry; Molzon, William; Lankford, Andrew; Taffard, Anyes; Whiteson, Daniel; Kirkby, David

    2013-07-25

    Work is reported in: Neutrino Physics, Cosmic Rays and Elementary Particles; Particle Physics and Charged Lepton Flavor Violation; Research in Collider Physics; Dark Energy Studies with BOSS and LSST.

  9. Teaching Elementary Probability Through its History.

    Science.gov (United States)

    Kunoff, Sharon; Pines, Sylvia

    1986-01-01

    Historical problems are presented which can readily be solved by students once some elementary probability concepts are developed. The Duke of Tuscany's Problem; the problem of points; and the question of proportions, divination, and Bertrand's Paradox are included. (MNS)

  10. Elementary process theory axiomatic introduction and applications

    CERN Document Server

    Cabbolet, Marcoen J T F

    2011-01-01

    Modern physics lacks a unitary theory that applies to all four fundamental interactions. This PhD thesis is a proposal for a single, complete, and coherent scheme of mathematically formulated elementary laws of nature. While the first chapter presents the general background, the second chapter addresses the method by which the main result has been developed. The next three chapters rigorously introduce the Elementary Process Theory, its mathematical foundations, and its applications to physics, cosmology and philosophy of mind. The final two chapters discuss the results and present the conclusions. Summarizing, the Elementary Process Theory is a scheme of seven well-formed closed expressions, written in the mathematical language of set matrix theory – a generalization of Zermelo-Fraenkel set theory. In the physical world, these seven expressions can be interpreted as elementary principles governing the universe at supersmall scale. The author critically confronts the theory with Quantum Mechanics and Genera...

  11. A Perspective on Teaching Elementary Statistics.

    Science.gov (United States)

    Wainwright, Barbara A.; Austin, Homer W.

    1997-01-01

    Shares the perspectives of two instructors of elementary statistics at the college level. Describes a course developed to increase statistics learning and student motivation to learn statistics by introducing writing into the course content. (DDR)

  12. Notices about using elementary statistics in psychology

    OpenAIRE

    松田, 文子; 三宅, 幹子; 橋本, 優花里; 山崎, 理央; 森田, 愛子; 小嶋, 佳子

    2003-01-01

    Improper uses of elementary statistics that were often observed in beginners' manuscripts and papers were collected and better ways were suggested. This paper consists of three parts: About descriptive statistics, multivariate analyses, and statistical tests.

  13. Scripted collaborative drawing in elementary science education

    NARCIS (Netherlands)

    van Dijk, Alieke Mattia; Gijlers, Aaltje H.; Weinberger, Armin

    2014-01-01

    Creating graphical representations can foster knowledge gains on science topics in elementary school students by promoting active integration and translation of new information. Collaborating on joint representations may encourage children to discuss and elaborate their knowledge. To foster producti

  14. BOOK REVIEW: Nonlinear Magnetohydrodynamics

    Science.gov (United States)

    Shafranov, V.

    1998-08-01

    's theory, to satisfy the above mentioned alignment of the vectors j and B. The details of this remarkable process are described. The final chapter is devoted to solar flares, which are as the author says `probably, the most spectacular eruptive events in cosmic plasmas'. This chapter describes in detail the structure of the solar convection zone and the solar atmosphere, considers the formation of the rope-like structure of the magnetic field and the thick flux tubes displayed as sunspots, as well as the buoyancy of the flux tubes and different models of the MHD processes leading to solar flares. In summary, the reviewed book is rich in content, reflecting the important issues of striking phenomena such as solar flares, the, quite dangerous for plasma confinement, major disruptions in tokamaks and the, conversely quite favourable for plasma confinement, non-linear process of L-H transition in tokamaks and continuous turbulent generation and maintenance of stabilizing toroidal magnetic fields in reversed field pinches, as well as other interesting MHD processes. The analysis of these very complicated phenomena is based on non-elementary mathematics. This could make it difficult for non-theoreticians to read some parts of the book. However, as for an explanation of the physics of the phenomena, the author achieves this in a rather simple manner: briefly, and with the minimal number of necessary formulas. This is done strictly without oversimplifications. This makes the book useful to both theoreticians and experimenters who wish to learn about non-linear processes such as disruptions and plasma self-organization.

  15. Multipolar nonlinear nanophotonics

    CERN Document Server

    Smirnova, Daria

    2016-01-01

    Nonlinear nanophotonics is a rapidly developing field with many useful applications for a design of nonlinear nanoantennas, light sources, nanolasers, sensors, and ultrafast miniature metadevices. A tight confinement of the local electromagnetic fields in resonant photonic nanostructures can boost nonlinear optical effects, thus offering versatile opportunities for subwavelength control of light. To achieve the desired functionalities, it is essential to gain flexible control over the near- and far-field properties of nanostructures. Thus, both modal and multipolar analyses are widely exploited for engineering nonlinear scattering from resonant nanoscale elements, in particular for enhancing the near-field interaction, tailoring the far-field multipolar interference, and optimization of the radiation directionality. Here, we review the recent advances in this recently emerged research field ranging from metallic structures exhibiting localized plasmonic resonances to hybrid metal-dielectric and all-dielectric...

  16. Solitons in nonlinear lattices

    CERN Document Server

    Kartashov, Yaroslav V; Torner, Lluis

    2010-01-01

    This article offers a comprehensive survey of results obtained for solitons and complex nonlinear wave patterns supported by purely nonlinear lattices (NLs), which represent a spatially periodic modulation of the local strength and sign of the nonlinearity, and their combinations with linear lattices. A majority of the results obtained, thus far, in this field and reviewed in this article are theoretical. Nevertheless, relevant experimental settings are surveyed too, with emphasis on perspectives for implementation of the theoretical predictions in the experiment. Physical systems discussed in the review belong to the realms of nonlinear optics (including artificial optical media, such as photonic crystals, and plasmonics) and Bose-Einstein condensation (BEC). The solitons are considered in one, two, and three dimensions (1D, 2D, and 3D). Basic properties of the solitons presented in the review are their existence, stability, and mobility. Although the field is still far from completion, general conclusions c...

  17. Nonlinear plasmonic antennas

    Directory of Open Access Journals (Sweden)

    Shakeeb Bin Hasan

    2014-12-01

    Full Text Available Contrary to traditional optical elements, plasmonic antennas made from nanostructured metals permit the localization of electromagnetic fields on length scales much smaller than the wavelength of light. This results in huge amplitudes for the electromagnetic field close to the antenna being conducive for the observation of nonlinear effects already at moderate pump powers. Thus, these antennas exhibit a promising potential to achieve optical frequency conversion and all-optical control of light at the nano-scale. This opens unprecedented opportunities for ultrafast nonlinear spectroscopy, sensing devices, on-chip optical frequency conversion, nonlinear optical metamaterials, and novel photon sources. Here, we review some of the recent advances in exploiting the potential of plasmonic antennas to realize robust nonlinear applications.

  18. Ultrafast nonlinear optics

    CERN Document Server

    Leburn, Christopher; Reid, Derryck

    2013-01-01

    The field of ultrafast nonlinear optics is broad and multidisciplinary, and encompasses areas concerned with both the generation and measurement of ultrashort pulses of light, as well as those concerned with the applications of such pulses. Ultrashort pulses are extreme events – both in terms of their durations, and also the high peak powers which their short durations can facilitate. These extreme properties make them powerful experiment tools. On one hand, their ultrashort durations facilitate the probing and manipulation of matter on incredibly short timescales. On the other, their ultrashort durations can facilitate high peak powers which can drive highly nonlinear light-matter interaction processes. Ultrafast Nonlinear Optics covers a complete range of topics, both applied and fundamental in nature, within the area of ultrafast nonlinear optics. Chapters 1 to 4 are concerned with the generation and measurement of ultrashort pulses. Chapters 5 to 7 are concerned with fundamental applications of ultrasho...

  19. Nonlinear Source Emulator

    DEFF Research Database (Denmark)

    Nguyen-Duy, Khiem

    and remains the prime source of energy in non-terrestrial applications such as those in sky-explorers. However, a renewable energy source is expensive, bulky, and its performance is weather dependent, which make testing of downstream converters very difficult. As a result, a nonlinear source emulator (NSE......) is a good solution to solve the problems associated with the use of real nonlinear sources in testing phases. However, a recent technical survey conducted during this work shows that most existing NSEs have only been concerned with simulating nonlinear systems in terrestrial applications. Furthermore......, their dynamic performance were not fast enough in order to imitate how a real nonlinear energy source would react under extreme conditions and operation modes. Particularly, a system in the sky can experience a step change of sunlight irradiation. Moreover, operation modes may include load step between nominal...

  20. Introduction to nonlinear science

    CERN Document Server

    Nicolis, G

    1995-01-01

    One of the most unexpected results in science in recent years is that quite ordinary systems obeying simple laws can give rise to complex, nonlinear or chaotic, behavior. In this book, the author presents a unified treatment of the concepts and tools needed to analyze nonlinear phenomena and to outline some representative applications drawn from the physical, engineering, and biological sciences. Some of the interesting topics covered include: dynamical systems with a finite number of degrees of freedom, linear stability analysis of fixed points, nonlinear behavior of fixed points, bifurcation analysis, spatially distributed systems, broken symmetries, pattern formation, and chaotic dynamics. The author makes a special effort to provide a logical connection between ordinary dynamical systems and spatially extended systems, and to balance the emphasis on chaotic behavior and more classical nonlinear behavior. He also develops a statistical approach to complex systems and compares it to traditional deterministi...

  1. Nonlinear magnetoinductive transmission lines

    CERN Document Server

    Lazarides, Nikos; Tsironis, G P

    2011-01-01

    Power transmission in one-dimensional nonlinear magnetic metamaterials driven at one end is investigated numerically and analytically in a wide frequency range. The nonlinear magnetic metamaterials are composed of varactor-loaded split-ring resonators which are coupled magnetically through their mutual inductances, forming thus a magnetoiductive transmission line. In the linear limit, significant power transmission along the array only appears for frequencies inside the linear magnetoinductive wave band. We present analytical, closed form solutions for the magnetoinductive waves transmitting the power in this regime, and their discrete frequency dispersion. When nonlinearity is important, more frequency bands with significant power transmission along the array may appear. In the equivalent circuit picture, the nonlinear magnetoiductive transmission line driven at one end by a relatively weak electromotive force, can be modeled by coupled resistive-inductive-capacitive (RLC) circuits with voltage-dependent cap...

  2. Optimization under Nonlinear Constraints

    OpenAIRE

    1982-01-01

    In this paper a timesaving method is proposed for maximizing likelihood functions when the parameter space is subject to nonlinear constraints, expressible as second order polynomials. The suggested approach is especially attractive when dealing with systems with many parameters.

  3. Nonlinearity in nanomechanical cantilevers

    DEFF Research Database (Denmark)

    Villanueva Torrijo, Luis Guillermo; Karabalin, R. B.; Matheny, M. H.

    2013-01-01

    Euler-Bernoulli beam theory is widely used to successfully predict the linear dynamics of micro-and nanocantilever beams. However, its capacity to characterize the nonlinear dynamics of these devices has not yet been rigorously assessed, despite its use in nanoelectromechanical systems development....... These findings underscore the delicate balance between inertial and geometric nonlinear effects in the fundamental mode, and strongly motivate further work to develop theories beyond the Euler-Bernoulli approximation. DOI: 10.1103/PhysRevB.87.024304....... In this article, we report the first highly controlled measurements of the nonlinear response of nanomechanical cantilevers using an ultralinear detection system. This is performed for an extensive range of devices to probe the validity of Euler-Bernoulli theory in the nonlinear regime. We find that its...

  4. Nonlinear Stokes Mueller Polarimetry

    CERN Document Server

    Samim, Masood; Barzda, Virginijus

    2015-01-01

    The Stokes Mueller polarimetry is generalized to include nonlinear optical processes such as second- and third-harmonic generation, sum- and difference-frequency generations. The overall algebraic form of the polarimetry is preserved, where the incoming and outgoing radiations are represented by column vectors and the intervening medium is represented by a matrix. Expressions for the generalized nonlinear Stokes vector and the Mueller matrix are provided in terms of coherency and correlation matrices, expanded by higher-dimensional analogues of Pauli matrices. In all cases, the outgoing radiation is represented by the conventional $4\\times 1$ Stokes vector, while dimensions of the incoming radiation Stokes vector and Mueller matrix depend on the order of the process being examined. In addition, relation between nonlinear susceptibilities and the measured Mueller matrices are explicitly provided. Finally, the approach of combining linear and nonlinear optical elements is discussed within the context of polarim...

  5. Foreign Language Activities in Hibizaki Elementary School

    OpenAIRE

    小野, 章

    2011-01-01

    Foreign language activities were introduced in Japanese elementary schools in April 2011. Hibizaki Municipal Elementary School in Onomichi City had been experimentally involved in the activities for six years between 2005 and 2010, and I witnessed them as an advisor. This paper aims to point out some characteristic features of the foreign language activities conducted in Hibizaki. First, the school has a clear vision of what the pupils should achieve through foreign language activities, and t...

  6. Elementary Components of the Quadratic Assignment Problem

    CERN Document Server

    Chicano, Francisco; Alba, Enrique

    2011-01-01

    The Quadratic Assignment Problem (QAP) is a well-known NP-hard combinatorial optimization problem that is at the core of many real-world optimization problems. We prove that QAP can be written as the sum of three elementary landscapes when the swap neighborhood is used. We present a closed formula for each of the three elementary components and we compute bounds for the autocorrelation coefficient.

  7. Elementary lesions in dermatological semiology: literature review*

    Science.gov (United States)

    Cardili, Renata Nahas; Roselino, Ana Maria

    2016-01-01

    Discrepancies in the terminology of elementary lesions persist when texts from Dermatology and Semiology books are compared, which can cause some confusion in both the teaching of undergraduate medical students and the learning acquired by professionals in the field. This review aims to compare and clarify the differences in the description of elementary lesions by many authors, used as references for specialists in dermatology. PMID:27828637

  8. Adaptive and Nonlinear Control

    Science.gov (United States)

    1992-02-29

    in [22], we also applied the concept of zero dynamics to the problem of exact linearization of a nonlinear control system by dynamic feedback. Exact ...nonlinear systems, although it was well-known that the conditions for exact linearization are very stringent and consequently do not apply to a broad...29th IEEE Conference n Decision and Control, Invited Paper delivered by Dr. Gilliam. Exact Linearization of Zero Dynamics, 29th IEEE Conference on

  9. Nonlinear Optics and Turbulence

    Science.gov (United States)

    1992-10-01

    currently at Queen Mary College, London Patrick Dunne, (Ph.D., 1987, M.I.T., Hydrodynamic Stability, Nonlinear Waves), 1987-1988. Alecsander Dyachenko...U I I I U I I 3 9 3 V. BIOGRAPHIES A. FACULTY BRUCE BAYLY, 31, Ph.D. 1986, Princeton University. Postdoctoral visiting member 1986-88 at Courant...Caputo, A. C. Newell, and M. Shelley , "Nonlinear Wave Propagation Through a Random Medium and Soliton Tunneling", Integrable Systems and

  10. Nonlinearly Coupled Superconducting Lumped Element Resonators

    Science.gov (United States)

    Collodo, Michele C.; Potočnik, Anton; Rubio Abadal, Antonio; Mondal, Mintu; Oppliger, Markus; Wallraff, Andreas

    We study SQUID-mediated tunable coupling between two superconducting on-chip resonators in the microwave frequency range. In this circuit QED implementation, we employ lumped-element type resonators, which consist of Nb thin film structured into interdigitated finger shunt capacitors and meander inductors. A SQUID, functioning as flux dependent and intrinsically nonlinear inductor, is placed as a coupling element together with an interdigitated capacitor between the two resonators (cf. A. Baust et al., Phys Rev. B 91 014515 (2015)). We perform a spectroscopic measurement in a dilution refrigerator and find the linear photon hopping rate between the resonators to be widely tunable as well as suppressible for an appropriate choice of parameters, which is made possible due to the interplay of inductively and capacitively mediated coupling. Vanishing linear coupling promotes nonlinear effects ranging from onsite- to cross-Kerr interaction. A dominating cross-Kerr interaction related to this configuration is notable, as it induces a unique quantum state. In the course of analog quantum simulations, such elementary building blocks can serve as a precursor for more complex geometries and thus pave the way to a number of novel quantum phases of light

  11. Robust Nonlinear Neural Codes

    Science.gov (United States)

    Yang, Qianli; Pitkow, Xaq

    2015-03-01

    Most interesting natural sensory stimuli are encoded in the brain in a form that can only be decoded nonlinearly. But despite being a core function of the brain, nonlinear population codes are rarely studied and poorly understood. Interestingly, the few existing models of nonlinear codes are inconsistent with known architectural features of the brain. In particular, these codes have information content that scales with the size of the cortical population, even if that violates the data processing inequality by exceeding the amount of information entering the sensory system. Here we provide a valid theory of nonlinear population codes by generalizing recent work on information-limiting correlations in linear population codes. Although these generalized, nonlinear information-limiting correlations bound the performance of any decoder, they also make decoding more robust to suboptimal computation, allowing many suboptimal decoders to achieve nearly the same efficiency as an optimal decoder. Although these correlations are extremely difficult to measure directly, particularly for nonlinear codes, we provide a simple, practical test by which one can use choice-related activity in small populations of neurons to determine whether decoding is suboptimal or optimal and limited by correlated noise. We conclude by describing an example computation in the vestibular system where this theory applies. QY and XP was supported by a grant from the McNair foundation.

  12. Nonlinear Multiantenna Detection Methods

    Directory of Open Access Journals (Sweden)

    Chen Sheng

    2004-01-01

    Full Text Available A nonlinear detection technique designed for multiple-antenna assisted receivers employed in space-division multiple-access systems is investigated. We derive the optimal solution of the nonlinear spatial-processing assisted receiver for binary phase shift keying signalling, which we refer to as the Bayesian detector. It is shown that this optimal Bayesian receiver significantly outperforms the standard linear beamforming assisted receiver in terms of a reduced bit error rate, at the expense of an increased complexity, while the achievable system capacity is substantially enhanced with the advent of employing nonlinear detection. Specifically, when the spatial separation expressed in terms of the angle of arrival between the desired and interfering signals is below a certain threshold, a linear beamformer would fail to separate them, while a nonlinear detection assisted receiver is still capable of performing adequately. The adaptive implementation of the optimal Bayesian detector can be realized using a radial basis function network. Two techniques are presented for constructing block-data-based adaptive nonlinear multiple-antenna assisted receivers. One of them is based on the relevance vector machine invoked for classification, while the other on the orthogonal forward selection procedure combined with the Fisher ratio class-separability measure. A recursive sample-by-sample adaptation procedure is also proposed for training nonlinear detectors based on an amalgam of enhanced -means clustering techniques and the recursive least squares algorithm.

  13. Nonlinear systems in medicine.

    Science.gov (United States)

    Higgins, John P

    2002-01-01

    Many achievements in medicine have come from applying linear theory to problems. Most current methods of data analysis use linear models, which are based on proportionality between two variables and/or relationships described by linear differential equations. However, nonlinear behavior commonly occurs within human systems due to their complex dynamic nature; this cannot be described adequately by linear models. Nonlinear thinking has grown among physiologists and physicians over the past century, and non-linear system theories are beginning to be applied to assist in interpreting, explaining, and predicting biological phenomena. Chaos theory describes elements manifesting behavior that is extremely sensitive to initial conditions, does not repeat itself and yet is deterministic. Complexity theory goes one step beyond chaos and is attempting to explain complex behavior that emerges within dynamic nonlinear systems. Nonlinear modeling still has not been able to explain all of the complexity present in human systems, and further models still need to be refined and developed. However, nonlinear modeling is helping to explain some system behaviors that linear systems cannot and thus will augment our understanding of the nature of complex dynamic systems within the human body in health and in disease states.

  14. Handbook of nonlinear optical crystals

    CERN Document Server

    Dmitriev, Valentin G; Nikogosyan, David N

    1991-01-01

    This Handbook of Nonlinear Optical Crystals provides a complete description of the properties and applications of nonlinear crystals In addition, it presents the most important equations for calculating the main parameters of nonlinear frequency converters This comprehensive reference work will be of great value to all scientists and engineers working in nonlinear optics, quantum electronics and laser physics

  15. Nonlinear Approaches in Engineering Applications

    CERN Document Server

    Jazar, Reza

    2012-01-01

    Nonlinear Approaches in Engineering Applications focuses on nonlinear phenomena that are common in the engineering field. The nonlinear approaches described in this book provide a sound theoretical base and practical tools to design and analyze engineering systems with high efficiency and accuracy and with less energy and downtime. Presented here are nonlinear approaches in areas such as dynamic systems, optimal control and approaches in nonlinear dynamics and acoustics. Coverage encompasses a wide range of applications and fields including mathematical modeling and nonlinear behavior as applied to microresonators, nanotechnologies, nonlinear behavior in soil erosion,nonlinear population dynamics, and optimization in reducing vibration and noise as well as vibration in triple-walled carbon nanotubes. This book also: Provides a complete introduction to nonlinear behavior of systems and the advantages of nonlinearity as a tool for solving engineering problems Includes applications and examples drawn from the el...

  16. Harmonic Oscillators and Elementary Particles

    CERN Document Server

    Sobouti, Y

    2016-01-01

    Two dynamical systems with same symmetry should have features in common, and as far as their shared symmetry is concerned, one may represent the other. The three light quark constituents of the hadrons, a) have an approximate flavor SU(3) symmetry, b) have an exact color SU(3) symmetry, and c) as spin 1/2 particles, have a Lorentz SO(3,1) symmetry. So does a 3D harmonic oscillator. a) Its Hamiltonian has the SU(3) symmetry, breakable if the 3 fundamental modes of oscillation are not identical. b) The 3 directions of oscillation have the permutation symmetry. This enables one to create three copies of unbreakable SU(3) symmetry for each mode of the oscillation, and mimic the color of the elementary particles. And c) The Lagrangian of the 3D oscillator has the SO(3,1) symmetry. This can be employed to accommodate the spin of the particles. In this paper we draw up a one-to-one correspondence between the eigen modes of the Poisson bracket operator of the 3D oscillator and the flavor multiplets of the particles, ...

  17. Preservice Elementary Teachers' Adaptation of Science Curriculum Materials for Inquiry-Based Elementary Science

    Science.gov (United States)

    Forbes, Cory T.

    2011-01-01

    Curriculum materials are important resources with which teachers make pedagogical decisions about the design of science learning environments. To become well-started beginning elementary teachers capable of engaging their students in inquiry-based science, preservice elementary teachers need to learn to use science curriculum materials…

  18. Higher-order modulation instability in nonlinear fiber optics.

    Science.gov (United States)

    Erkintalo, Miro; Hammani, Kamal; Kibler, Bertrand; Finot, Christophe; Akhmediev, Nail; Dudley, John M; Genty, Goëry

    2011-12-16

    We report theoretical, numerical, and experimental studies of higher-order modulation instability in the focusing nonlinear Schrödinger equation. This higher-order instability arises from the nonlinear superposition of elementary instabilities, associated with initial single breather evolution followed by a regime of complex, yet deterministic, pulse splitting. We analytically describe the process using the Darboux transformation and compare with experiments in optical fiber. We show how a suitably low frequency modulation on a continuous wave field induces higher-order modulation instability splitting with the pulse characteristics at different phases of evolution related by a simple scaling relationship. We anticipate that similar processes are likely to be observed in many other systems including plasmas, Bose-Einstein condensates, and deep water waves.

  19. Lectures on nonlinear evolution equations initial value problems

    CERN Document Server

    Racke, Reinhard

    2015-01-01

    This book mainly serves as an elementary, self-contained introduction to several important aspects of the theory of global solutions to initial value problems for nonlinear evolution equations. The book employs the classical method of continuation of local solutions with the help of a priori estimates obtained for small data. The existence and uniqueness of small, smooth solutions that are defined for all values of the time parameter are investigated. Moreover, the asymptotic behavior of the solutions is described as time tends to infinity. The methods for nonlinear wave equations are discussed in detail. Other examples include the equations of elasticity, heat equations, the equations of thermoelasticity, Schrödinger equations, Klein-Gordon equations, Maxwell equations and plate equations. To emphasize the importance of studying the conditions under which small data problems offer global solutions, some blow-up results are briefly described. Moreover, the prospects for corresponding initial-boundary value p...

  20. Nonlinear pulsation masses

    Energy Technology Data Exchange (ETDEWEB)

    Davis, C.G.

    1990-01-01

    The advent of nonlinear pulsation theory really coincides with the development of the large computers after the second world war. Christy and Stobbie were the first to make use of finite difference techniques on computers to model the bumps'' observed in the classical Cepheid light and velocity curves, the so-called Hertzsprung'' sequence. Following this work a more sophisticated analysis of the light and velocity curves from the models was made by Simon and Davis using Fourier techniques. Recently a simpler amplitude equation formalism has been developed that helps explain this resonance mechanism. The determination of Population I Cepheid masses by nonlinear methods will be discussed. For the lower mass objects, such as RR Lyrae and BL Her. stars, we find general agreement using evolutionary masses and nonlinear pulsation theory. An apparent difficulty of nonlinear pulsation theory occurs in the understanding of double'' mode pulsation, which will also be discussed. Recent studies in nonlinear pulsation theory have dealt with the question of mode selection, period doubling and the trends towards chaotic behavior such as is observed in the transition from W Virginis to RV Tauri-like stars. 10 refs., 1 fig., 2 tabs.

  1. Exact travelling solutions for some nonlinear physical models by (′/)-expansion method

    Indian Academy of Sciences (India)

    B Salim Bahrami; H Abdollahzadeh; I M Berijani; D D Ganji; M Abdollahzadeh

    2011-08-01

    In this paper, we establish exact solutions for some special nonlinear partial differential equations. The (′/)-expansion method is used to construct travelling wave solutions of the twodimensional sine-Gordon equation, Dodd–Bullough–Mikhailov and Schrödinger–KdV equations, which appear in many fields such as, solid-state physics, nonlinear optics, fluid dynamics, fluid flow, quantum field theory, electromagnetic waves and so on. In this method we take the advantage of general solutions of second-order linear ordinary differential equation (LODE) to solve many nonlinear evolution equations effectively. The (′/)-expansion method is direct, concise and elementary and can be used with a wider applicability for handling many nonlinear wave equations.

  2. Elementary quadratic chaotic flows with a single non-hyperbolic equilibrium

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Zhouchao, E-mail: weizhouchao@163.com [School of Mathematics and Physics, China University of Geosciences, Wuhan, 430074 (China); College of Mechanical Engineering, Beijing University of Technology, Beijing, 100124 (China); Mathematical Institute, University of Oxford, Oxford (United Kingdom); Sprott, J.C., E-mail: sprott@physics.wisc.edu [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Chen, Huai [Faculty of Earth Sciences, China University of Geosciences, Wuhan, 430074 (China)

    2015-10-02

    Highlights: • A kind of jerk equations are proposed. • Chaos can occur with all types of a non-hyperbolic equilibrium. • The mechanism of generating chaos is discussed. • Feigenbaum's constant explains the identified chaotic flows. - Abstract: This paper describes a class of third-order explicit autonomous differential equations, called jerk equations, with quadratic nonlinearities that can generate a catalog of nine elementary dissipative chaotic flows with the unusual feature of having a single non-hyperbolic equilibrium. They represent an interesting sub-class of dynamical systems that can exhibit many major features of regular and chaotic motion. The proposed systems are investigated through numerical simulations and theoretical analysis. For these jerk dynamical systems, a certain amount of nonlinearity is sufficient to produce chaos through a sequence of period-doubling bifurcations.

  3. Nonlinear elastic waves in materials

    CERN Document Server

    Rushchitsky, Jeremiah J

    2014-01-01

    The main goal of the book is a coherent treatment of the theory of propagation in materials of nonlinearly elastic waves of displacements, which corresponds to one modern line of development of the nonlinear theory of elastic waves. The book is divided on five basic parts: the necessary information on waves and materials; the necessary information on nonlinear theory of elasticity and elastic materials; analysis of one-dimensional nonlinear elastic waves of displacement – longitudinal, vertically and horizontally polarized transverse plane nonlinear elastic waves of displacement; analysis of one-dimensional nonlinear elastic waves of displacement – cylindrical and torsional nonlinear elastic waves of displacement; analysis of two-dimensional nonlinear elastic waves of displacement – Rayleigh and Love nonlinear elastic surface waves. The book is addressed first of all to people working in solid mechanics – from the students at an advanced undergraduate and graduate level to the scientists, professional...

  4. Nonlinear Dynamic Force Spectroscopy

    CERN Document Server

    Björnham, Oscar

    2016-01-01

    Dynamic force spectroscopy (DFS) is an experimental technique that is commonly used to assess information of the strength, energy landscape, and lifetime of noncovalent bio-molecular interactions. DFS traditionally requires an applied force that increases linearly with time so that the bio-complex under investigation is exposed to a constant loading rate. However, tethers or polymers can modulate the applied force in a nonlinear regime. For example, bacterial adhesion pili and polymers with worm-like chain properties are examples of structures that show nonlinear force responses. In these situations, the theory for traditional DFS cannot be readily applied. In this work we expand the theory for DFS to also include nonlinear external forces while still maintaining compatibility with the linear DFS theory. To validate the theory we modeled a bio-complex expressed on a stiff, an elastic and a worm-like chain polymer, using Monte Carlo methods, and assessed the corresponding rupture force spectra. It was found th...

  5. Nonlinear optomechanical paddle nanocavities

    CERN Document Server

    Kaviani, Hamidreza; Wu, Marcelo; Ghobadi, Roohollah; Barclay, Paul E

    2014-01-01

    A photonic crystal optomechanical system combining strong nonlinear optomechanical coupling, low effective mass and large optical mode spacing is introduced. This nanoscale "paddle nanocavity" device supports mechanical resonances with effective mass of 300--600 fg which couple nonlinearly to co-localized optical modes with a quadratic optomechanical coupling coefficient $g^{(2)} > 2\\pi\\times400$ MHz/nm$^2$, and a two phonon to single photon optomechanical coupling rate $\\Delta \\omega_0 > 2\\pi\\times 16$ Hz. This coupling relies on strong phonon-photon interactions in a structure whose optical mode spectrum is highly non--degenerate. Simulations indicate that nonlinear optomechanical readout of thermally driven motion in these devices should be observable for T $> 50 $ mK, and that measurement of phonon shot noise is achievable.

  6. Nonlinear dynamics of structures

    CERN Document Server

    Oller, Sergio

    2014-01-01

    This book lays the foundation of knowledge that will allow a better understanding of nonlinear phenomena that occur in structural dynamics.   This work is intended for graduate engineering students who want to expand their knowledge on the dynamic behavior of structures, specifically in the nonlinear field, by presenting the basis of dynamic balance in non‐linear behavior structures due to the material and kinematics mechanical effects.   Particularly, this publication shows the solution of the equation of dynamic equilibrium for structure with nonlinear time‐independent materials (plasticity, damage and frequencies evolution), as well as those time dependent non‐linear behavior materials (viscoelasticity and viscoplasticity). The convergence conditions for the non‐linear dynamic structure solution  are studied, and the theoretical concepts and its programming algorithms are presented.  

  7. Nonlinear Photonic Crystal Fibers

    DEFF Research Database (Denmark)

    Hansen, Kim Per

    2004-01-01

    , leading to reduced mode confinement and dispersion flexibility. In this thesis, we treat the nonlinear photonic crystal fiber – a special sub-class of photonic crystal fibers, the core of which has a diameter comparable to the wavelength of the light guided in the fiber. The small core results in a large...... nonlinear coefficient and in various applications, it is therefore possible to reduce the required fiber lengths quite dramatically, leading to increased stability and efficiency. Furthermore, it is possible to design these fibers with zero-dispersion at previously unreachable wavelengths, paving the way...... for completely new applications, especially in and near the visible wavelength region. One such application is supercontinuum generation. Supercontinuum generation is extreme broadening of pulses in a nonlinear medium (in this case a small-core fiber), and depending on the dispersion of the fiber, it is possible...

  8. Linearizing nonlinear optics

    CERN Document Server

    Schmidt, Bruno E; Ernotte, Guilmot; Clerici, Matteo; Morandotti, Roberto; Ibrahim, Heide; Legare, Francois

    2016-01-01

    In the framework of linear optics, light fields do not interact with each other in a medium. Yet, when their field amplitude becomes comparable to the electron binding energies of matter, the nonlinear motion of these electrons emits new dipole radiation whose amplitude, frequency and phase differ from the incoming fields. Such high fields are typically achieved with ultra-short, femtosecond (1fs = 10-15 sec.) laser pulses containing very broad frequency spectra. Here, the matter not only couples incoming and outgoing fields but also causes different spectral components to interact and mix through a convolution process. In this contribution, we describe how frequency domain nonlinear optics overcomes the shortcomings arising from this convolution in conventional time domain nonlinear optics1. We generate light fields with previously inaccessible properties because the uncontrolled coupling of amplitudes and phases is turned off. For example, arbitrary phase functions are transferred linearly to the second har...

  9. Nonlinear optomechanics with graphene

    Science.gov (United States)

    Shaffer, Airlia; Patil, Yogesh Sharad; Cheung, Hil F. H.; Wang, Ke; Vengalattore, Mukund

    2016-05-01

    To date, studies of cavity optomechanics have been limited to exploiting the linear interactions between the light and mechanics. However, investigations of quantum signal transduction, quantum enhanced metrology and manybody physics with optomechanics each require strong, nonlinear interactions. Graphene nanomembranes are an exciting prospect for realizing such studies due to their inherently nonlinear nature and low mass. We fabricate large graphene nanomembranes and study their mechanical and optical properties. By using dark ground imaging techniques, we correlate their eigenmode shapes with the measured dissipation. We study their hysteretic response present even at low driving amplitudes, and their nonlinear dissipation. Finally, we discuss ongoing efforts to use these resonators for studies of quantum optomechanics and force sensing. This work is supported by the DARPA QuASAR program through a Grant from the ARO.

  10. Nonlinear Analysis of Buckling

    Directory of Open Access Journals (Sweden)

    Psotný Martin

    2014-06-01

    Full Text Available The stability analysis of slender web loaded in compression was presented. To solve this problem, a specialized computer program based on FEM was created. The nonlinear finite element method equations were derived from the variational principle of minimum of potential energy. To obtain the nonlinear equilibrium paths, the Newton-Raphson iteration algorithm was used. Corresponding levels of the total potential energy were defined. The peculiarities of the effects of the initial imperfections were investigated. Special attention was focused on the influence of imperfections on the post-critical buckling mode. The stable and unstable paths of the nonlinear solution were separated. Obtained results were compared with those gained using ANSYS system.

  11. Nonlinear Metamaterials for Holography

    CERN Document Server

    Almeida, Euclides; Prior, Yehiam

    2015-01-01

    A hologram is an optical element storing phase and possibly amplitude information enabling the reconstruction of a three dimensional image of an object by illumination and scattering of a coherent beam of light, and the image is generated at the same wavelength as the input laser beam. In recent years it was shown that information can be stored in nanometric antennas giving rise to ultrathin components. Here we demonstrate nonlinear multi-layer metamaterial holograms where by the nonlinear process of Third Harmonic Generation, a background free image is formed at a new frequency which is the third harmonic of the illuminating beam. Using e-beam lithography of multilayer plasmonic nanoantennas, we fabricate polarization-sensitive nonlinear elements such as blazed gratings, lenses and other computer-generated holograms. These holograms are analyzed and prospects for future device applications are discussed.

  12. Multidimensional nonlinear descriptive analysis

    CERN Document Server

    Nishisato, Shizuhiko

    2006-01-01

    Quantification of categorical, or non-numerical, data is a problem that scientists face across a wide range of disciplines. Exploring data analysis in various areas of research, such as the social sciences and biology, Multidimensional Nonlinear Descriptive Analysis presents methods for analyzing categorical data that are not necessarily sampled randomly from a normal population and often involve nonlinear relations. This reference not only provides an overview of multidimensional nonlinear descriptive analysis (MUNDA) of discrete data, it also offers new results in a variety of fields. The first part of the book covers conceptual and technical preliminaries needed to understand the data analysis in subsequent chapters. The next two parts contain applications of MUNDA to diverse data types, with each chapter devoted to one type of categorical data, a brief historical comment, and basic skills peculiar to the data types. The final part examines several problems and then concludes with suggestions for futu...

  13. Nonlinear airship aeroelasticity

    Science.gov (United States)

    Bessert, N.; Frederich, O.

    2005-12-01

    The aeroelastic derivatives for today's aircraft are calculated in the concept phase using a standard procedure. This scheme has to be extended for large airships, due to various nonlinearities in structural and aerodynamic behaviour. In general, the structural model of an airship is physically as well as geometrically nonlinear. The main sources of nonlinearity are large deformations and the nonlinear material behaviour of membranes. The aerodynamic solution is also included in the nonlinear problem, because the deformed airship influences the surrounding flow. Due to these nonlinearities, the aeroelastic problem for airships can only be solved by an iterative procedure. As one possibility, the coupled aerodynamic and structural dynamic problem was handled using linked standard solvers. On the structural side, the Finite-Element program package ABAQUS was extended with an interface to the aerodynamic solver VSAERO. VSAERO is based on the aerodynamic panel method using potential flow theory. The equilibrium of the internal structural and the external aerodynamic forces leads to the structural response and a trimmed flight state for the specified flight conditions (e.g. speed, altitude). The application of small perturbations around a trimmed state produces reaction forces and moments. These constraint forces are then transferred into translational and rotational acceleration fields by performing an inertia relief analysis of the disturbed structural model. The change between the trimmed flight state and the disturbed one yields the respective aeroelastic derivatives. By including the calculated derivatives in the linearised equation of motion system, it is possible to judge the stability and controllability of the investigated airship.

  14. A Fabry-Perot interferometer with quantum mirrors: nonlinear light transport and rectification

    CERN Document Server

    Fratini, F; Safari, L; Poizat, J-Ph; Valente, D; Auffèves, A; Gerace, D; Santos, M F

    2014-01-01

    Optical transport represents a natural route towards fast communications, and it is currently used in large scale data transfer. The progressive miniaturization of devices for information processing calls for the microscopic tailoring of light transport and confinement at length scales appropriate for the upcoming technologies. With this goal in mind, we present a theoretical analysis of a one-dimensional Fabry-Perot interferometer built with two highly saturable nonlinear mirrors: a pair of two-level systems. Our approach captures non-linear and non-reciprocal effects of light transport that were not reported previously. Remarkably, we show that such an elementary device can operate as a microscopic integrated optical rectifier.

  15. Nonlinear fiber optics

    CERN Document Server

    Agrawal, Govind

    2012-01-01

    Since the 4e appeared, a fast evolution of the field has occurred. The 5e of this classic work provides an up-to-date account of the nonlinear phenomena occurring inside optical fibers, the basis of all our telecommunications infastructure as well as being used in the medical field. Reflecting the big developments in research, this new edition includes major new content: slow light effects, which offers a reduction in noise and power consumption and more ordered network traffic-stimulated Brillouin scattering; vectorial treatment of highly nonlinear fibers; and a brand new chapter o

  16. Limits to Nonlinear Inversion

    DEFF Research Database (Denmark)

    Mosegaard, Klaus

    2012-01-01

    For non-linear inverse problems, the mathematical structure of the mapping from model parameters to data is usually unknown or partly unknown. Absence of information about the mathematical structure of this function prevents us from presenting an analytical solution, so our solution depends on our......-heuristics are inefficient for large-scale, non-linear inverse problems, and that the 'no-free-lunch' theorem holds. We discuss typical objections to the relevance of this theorem. A consequence of the no-free-lunch theorem is that algorithms adapted to the mathematical structure of the problem perform more efficiently than...

  17. Fundamentals of nonlinear optics

    CERN Document Server

    Powers, Peter E

    2011-01-01

    Peter Powers's rigorous but simple description of a difficult field keeps the reader's attention throughout. … All chapters contain a list of references and large numbers of practice examples to be worked through. … By carefully working through the proposed problems, students will develop a sound understanding of the fundamental principles and applications. … the book serves perfectly for an introductory-level course for second- and third-order nonlinear optical phenomena. The author's writing style is refreshing and original. I expect that Fundamentals of Nonlinear Optics will fast become pop

  18. Tunable nonlinear graphene metasurfaces

    CERN Document Server

    Smirnova, Daria A; Kivshar, Yuri S; Khanikaev, Alexander B

    2015-01-01

    We introduce the concept of nonlinear graphene metasurfaces employing the controllable interaction between a graphene layer and a planar metamaterial. Such hybrid metasurfaces support two types of subradiant resonant modes, asymmetric modes of structured metamaterial elements ("metamolecules") and graphene plasmons exhibiting strong mutual coupling and avoided dispersion crossing. High tunability of graphene plasmons facilitates strong interaction between the subradiant modes, modifying the spectral position and lifetime of the associated Fano resonances. We demonstrate that strong resonant interaction, combined with the subwavelength localization of plasmons, leads to the enhanced nonlinear response and high efficiency of the second-harmonic generation.

  19. Nonlinear effects in optical fibers

    CERN Document Server

    Ferreira, Mario F

    2011-01-01

    Cutting-edge coverage of nonlinear phenomena occurring inside optical fibers Nonlinear fiber optics is a specialized part of fiber optics dealing with optical nonlinearities and their applications. As fiber-optic communication systems have become more advanced and complex, the nonlinear effects in optical fibers have increased in importance, as they adversely affect system performance. Paradoxically, the same nonlinear phenomena also offer the promise of addressing the bandwidth bottleneck for signal processing for future ultra-high speed optical networks. Nonlinear Effects in Optical Fiber

  20. Fractional quantum Hall edge: Effect of nonlinear dispersion and edge roton

    OpenAIRE

    Jolad, Shivakumar; Sen, Diptiman; Jain, Jainendra K.

    2010-01-01

    According to Wen's theory, a universal behavior of the fractional quantum Hall edge is expected at sufficiently low energies, where the dispersion of the elementary edge excitation is linear. A microscopic calculation shows that the actual dispersion is indeed linear at low energies, but deviates from linearity beyond certain energy, and also exhibits an "edge roton minimum." We determine the edge exponent from a microscopic approach, and find that the nonlinearity of the dispersion makes a s...

  1. Stability of planar diffusion wave for nonlinear evolution equation

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    It is known that the one-dimensional nonlinear heat equation ut = f(u)x1x1,f'(u) 0,u(±∞,t) = u±,u+ = u_ has a unique self-similar solution u(x1/1+t).In multi-dimensional space,u(x1/1+t) is called a planar diffusion wave.In the first part of the present paper,it is shown that under some smallness conditions,such a planar diffusion wave is nonlinearly stable for the nonlinear heat equation:ut-△f(u) = 0,x ∈ Rn.The optimal time decay rate is obtained.In the second part of this paper,it is further shown that this planar diffusion wave is still nonlinearly stable for the quasilinear wave equation with damping:utt + utt+ △f(u) = 0,x ∈ Rn.The time decay rate is also obtained.The proofs are given by an elementary energy method.

  2. Norms of certain Jordan elementary operators

    Science.gov (United States)

    Zhang, Xiaoli; Ji, Guoxing

    2008-10-01

    Let be a complex Hilbert space and let denote the algebra of all bounded linear operators on . For , the Jordan elementary operator UA,B is defined by UA,B(X)=AXB+BXA, . In this short note, we discuss the norm of UA,B. We show that if and ||UA,B||=||A||||B||, then either AB* or B*A is 0. We give some examples of Jordan elementary operators UA,B such that ||UA,B||=||A||||B|| but AB*[not equal to]0 and B*A[not equal to]0, which answer negatively a question posed by M. Boumazgour in [M. Boumazgour, Norm inequalities for sums of two basic elementary operators, J. Math. Anal. Appl. 342 (2008) 386-393].

  3. Do elementary particles survive composite systems?

    CERN Document Server

    Nagahiro, Hideko

    2014-01-01

    The "compositeness" or "elementarity" is investigated for s-wave composite states dynamically generated by energy-dependent and independent interactions. The bare mass of the corresponding fictitious elementary particle in an equivalent Yukawa model is shown to be infinite, indicating that the wave function renormalization constant Z is equal to zero. The idea can be equally applied to both resonant and bound states. In a special case of zero-energy bound states, the condition Z = 0 does not necessarily mean that the elementary particle has the infinite bare mass. We also emphasize arbitrariness in the "elementarity" leading to multiple interpretations of a physical state, which can be either a pure composite state with Z = 0 or an elementary particle with Z \

  4. Elementary particle physics in early physics education

    CERN Document Server

    Wiener, Gerfried

    2017-01-01

    Current physics education research is faced with the important question of how best to introduce elementary particle physics in the classroom early on. Therefore, a learning unit on the subatomic structure of matter was developed, which aims to introduce 12-year-olds to elementary particles and fundamental interactions. This unit was iteratively evaluated and developed by means of a design-based research project with grade-6 students. In addition, dedicated professional development programmes were set up to instruct high school teachers about the learning unit and enable them to investigate its didactical feasibility. Overall, the doctoral research project led to successful results and showed the topic of elementary particle physics to be a viable candidate for introducing modern physics in the classroom. Furthermore, thanks to the design-based research methodology, the respective findings have implications for both physics education and physics education research, which will be presented during the PhD defen...

  5. The Elementary Private School Recognition Program: Mike Mulligan's View.

    Science.gov (United States)

    Lodish, Richard

    1986-01-01

    Describes the goals, the selection criteria, and the selection process of the Elementary Private School Recognition Program. Includes a listing, by states, of the 60 private elementary schools selected for 1985-86 recognition. (IW)

  6. Schools K-12 - MDC_ElementaryAttendanceBoundary

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Polygon feature class of Miami-Dade County, Public Schools attendance zones for Elementary schools (PK-5) and K-8 Centers (PK-8) schools. K-8 Centers are elementary...

  7. Nonlinear elliptic systems with exponential nonlinearities

    Directory of Open Access Journals (Sweden)

    Said El Manouni

    2002-12-01

    Full Text Available In this paper we investigate the existence of solutions for {gather*} -mathop{m div}( a(| abla u | ^N| abla u |^{N-2}u = f(x,u,v quad mbox{in } Omega -mathop{m div}(a(| abla v| ^N| abla v |^{N-2}v = g(x,u,v quad mbox{in } Omega u(x = v(x = 0 quad mbox{on }partial Omega. end{gather*} Where $Omega$ is a bounded domain in ${mathbb{R}}^N$, $Ngeq 2$, $f$ and $g$ are nonlinearities having an exponential growth on $Omega$ and $a$ is a continuous function satisfying some conditions which ensure the existence of solutions.

  8. Nonlinearity and disorder: Classification and stability of nonlinear impurity modes

    DEFF Research Database (Denmark)

    Sukhorukov, Andrey A.; Kivshar, Yuri S.; Bang, Ole

    2001-01-01

    We study the effects produced by competition of two physical mechanisms of energy localization in inhomogeneous nonlinear systems. As an example, we analyze spatially localized modes supported by a nonlinear impurity in the generalized nonlinear Schrödinger equation and describe three types of no...

  9. Kinetic studies of elementary chemical reactions

    Energy Technology Data Exchange (ETDEWEB)

    Durant, J.L. Jr. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    This program concerning kinetic studies of elementary chemical reactions is presently focussed on understanding reactions of NH{sub x} species. To reach this goal, the author is pursuing experimental studies of reaction rate coefficients and product branching fractions as well as using electronic structure calculations to calculate transition state properties and reaction rate calculations to relate these properties to predicted kinetic behavior. The synergy existing between the experimental and theoretical studies allow one to gain a deeper insight into more complex elementary reactions.

  10. Observations on English education in elementary schools

    OpenAIRE

    藤澤, 良行; カドゥアー, ドナルド; フジサワ, ヨシユキ; Donald, KADUHR; Yoshiyuki, FUJISAWA

    2009-01-01

    This paper examines English-language teaching in the People's Republic of China through visitations to some elementary school grades in two large urban centres, Beijing and Dalian, in March 2008. Observations of English classes in China for students in grades 1 to 6, provide the basis of what we feel needs to be addressed for the implementation of English-language teaching in lower levels of Japanese elementary schools (grade 5 and above) from 2011. After giving a brief overview of the develo...

  11. Beam Line: 100 years of elementary particles

    Science.gov (United States)

    Pais, A.; Weinberg, S.; Quigg, C.; Riordan, M.; Panofsky, W. K. H.

    1997-04-01

    This issue of Beam Line commemorates the 100th anniversary of the April 30, 1897 report of the discovery of the electron by J.J. Thomson and the ensuing discovery of other subatomic particles. In the first three articles, theorists Abraham Pais, Steven Weinberg, and Chris Quigg provide their perspectives on the discoveries of elementary particles as well as the implications and future directions resulting from these discoveries. In the following three articles, Michael Riordan, Wolfgang Panofsky, and Virginia Trimble apply our knowledge about elementary particles to high-energy research, electronics technology, and understanding the origin and evolution of our Universe.

  12. Elementary school teachers and successful science fairs

    Science.gov (United States)

    Cook, Helen Mounce

    The purpose of this research was to examine the knowledge, skills and attitudes of elementary school teachers who have led their students to successful experiences in science fairs. Six research questions guided the study: (1) What knowledge, skills and attitudes do the five selected elementary school teachers draw upon to enable their students to have a successful science fair experience? (2) How do the five selected elementary school teachers enable their students to have a successful science fair experience? (3) Why are the five selected elementary school teachers capable of enabling their students to have a successful science fair experience? (4) How do the knowledge, skills and attitudes of the five selected elementary school teachers compare to the knowledge, skills and attitudes that the National Science Education Standards (National Research Council, 1996) recommend for science teachers? (5) What are the commonalities in the knowledge, skills and attitudes among the five selected elementary school teachers who enable their students to have a successful science fair experience? (6) What are the differences in the knowledge, skills and attitudes among the five selected elementary school teachers who enable their students to have a successful science fair experience? A qualitative multiple-case research design was used to focus on five elementary school teachers who have a history of leading their students to successful experiences in science fairs. Data sources included classroom observations, formal and informal interviews, focus groups, science fair visitations and perusal of documents related to the teachers' science fair preparation of their students. In addition, questionnaires were given to the teachers and their students assessing their views about science and science fairs. A cross-case analysis revealed that the teachers had become knowledgeable about science fairs and science by non-traditional means including attending staff development workshops

  13. Generalized Nonlinear Yule Models

    Science.gov (United States)

    Lansky, Petr; Polito, Federico; Sacerdote, Laura

    2016-10-01

    With the aim of considering models related to random graphs growth exhibiting persistent memory, we propose a fractional nonlinear modification of the classical Yule model often studied in the context of macroevolution. Here the model is analyzed and interpreted in the framework of the development of networks such as the World Wide Web. Nonlinearity is introduced by replacing the linear birth process governing the growth of the in-links of each specific webpage with a fractional nonlinear birth process with completely general birth rates. Among the main results we derive the explicit distribution of the number of in-links of a webpage chosen uniformly at random recognizing the contribution to the asymptotics and the finite time correction. The mean value of the latter distribution is also calculated explicitly in the most general case. Furthermore, in order to show the usefulness of our results, we particularize them in the case of specific birth rates giving rise to a saturating behaviour, a property that is often observed in nature. The further specialization to the non-fractional case allows us to extend the Yule model accounting for a nonlinear growth.

  14. Nonlinear Regression with R

    CERN Document Server

    Ritz, Christian; Parmigiani, Giovanni

    2009-01-01

    R is a rapidly evolving lingua franca of graphical display and statistical analysis of experiments from the applied sciences. This book provides a coherent treatment of nonlinear regression with R by means of examples from a diversity of applied sciences such as biology, chemistry, engineering, medicine and toxicology.

  15. Methods of nonlinear kinetics

    OpenAIRE

    Gorban, A. N.; Karlin, I.V.

    2003-01-01

    Nonlinear kinetic equations are reviewed for a wide audience of specialists and postgraduate students in physics, mathematical physics, material science, chemical engineering and interdisciplinary research. Contents: The Boltzmann equation, Phenomenology and Quasi-chemical representation of the Boltzmann equation, Kinetic models, Discrete velocity models, Direct simulation, Lattice Gas and Lattice Boltzmann models, Minimal Boltzmann models for flows at low Knudsen number, Other kinetic equati...

  16. Intramolecular and nonlinear dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Davis, M.J. [Argonne National Laboratory, IL (United States)

    1993-12-01

    Research in this program focuses on three interconnected areas. The first involves the study of intramolecular dynamics, particularly of highly excited systems. The second area involves the use of nonlinear dynamics as a tool for the study of molecular dynamics and complex kinetics. The third area is the study of the classical/quantum correspondence for highly excited systems, particularly systems exhibiting classical chaos.

  17. Nonlinear Hamiltonian systems

    DEFF Research Database (Denmark)

    Jørgensen, Michael Finn

    1995-01-01

    It is generally very difficult to solve nonlinear systems, and such systems often possess chaotic solutions. In the rare event that a system is completely solvable, it is said to integrable. Such systems never have chaotic solutions. Using the Inverse Scattering Transform Method (ISTM) two...

  18. Nonlinear phased array imaging

    Science.gov (United States)

    Croxford, Anthony J.; Cheng, Jingwei; Potter, Jack N.

    2016-04-01

    A technique is presented for imaging acoustic nonlinearity within a specimen using ultrasonic phased arrays. Acoustic nonlinearity is measured by evaluating the difference in energy of the transmission bandwidth within the diffuse field produced through different focusing modes. The two different modes being classical beam forming, where delays are applied to different element of a phased array to physically focus the energy at a single location (parallel firing) and focusing in post processing, whereby one element at a time is fired and a focused image produced in post processing (sequential firing). Although these two approaches are linearly equivalent the difference in physical displacement within the specimen leads to differences in nonlinear effects. These differences are localized to the areas where the amplitude is different, essentially confining the differences to the focal point. Direct measurement at the focal point are however difficult to make. In order to measure this the diffuse field is used. It is a statistical property of the diffuse field that it represents the total energy in the system. If the energy in the diffuse field for both the sequential and parallel firing case is measured then the difference between these, within the input signal bandwidth, is largely due to differences at the focal spot. This difference therefore gives a localized measurement of where energy is moving out of the transmission bandwidth due to nonlinear effects. This technique is used to image fatigue cracks and other damage types undetectable with conventional linear ultrasonic measurements.

  19. Generalized Nonlinear Yule Models

    Science.gov (United States)

    Lansky, Petr; Polito, Federico; Sacerdote, Laura

    2016-11-01

    With the aim of considering models related to random graphs growth exhibiting persistent memory, we propose a fractional nonlinear modification of the classical Yule model often studied in the context of macroevolution. Here the model is analyzed and interpreted in the framework of the development of networks such as the World Wide Web. Nonlinearity is introduced by replacing the linear birth process governing the growth of the in-links of each specific webpage with a fractional nonlinear birth process with completely general birth rates. Among the main results we derive the explicit distribution of the number of in-links of a webpage chosen uniformly at random recognizing the contribution to the asymptotics and the finite time correction. The mean value of the latter distribution is also calculated explicitly in the most general case. Furthermore, in order to show the usefulness of our results, we particularize them in the case of specific birth rates giving rise to a saturating behaviour, a property that is often observed in nature. The further specialization to the non-fractional case allows us to extend the Yule model accounting for a nonlinear growth.

  20. Trirefringence in nonlinear metamaterials

    CERN Document Server

    De Lorenci, Vitorio A

    2012-01-01

    We study the propagation of electromagnetic waves in the limit of geometrical optics for a class of nearly transparent nonlinear uniaxial metamaterials for which their permittivity tensors present a negative principal component. Their permeability are assumed positive and dependent on the electric field. We show that light waves experience triple refraction -- trirefringence. Additionally to the ordinary wave, two extraordinary waves propagate in such media.

  1. Nonlinear silicon photonics

    Science.gov (United States)

    Borghi, M.; Castellan, C.; Signorini, S.; Trenti, A.; Pavesi, L.

    2017-09-01

    Silicon photonics is a technology based on fabricating integrated optical circuits by using the same paradigms as the dominant electronics industry. After twenty years of fervid development, silicon photonics is entering the market with low cost, high performance and mass-manufacturable optical devices. Until now, most silicon photonic devices have been based on linear optical effects, despite the many phenomenologies associated with nonlinear optics in both bulk materials and integrated waveguides. Silicon and silicon-based materials have strong optical nonlinearities which are enhanced in integrated devices by the small cross-section of the high-index contrast silicon waveguides or photonic crystals. Here the photons are made to strongly interact with the medium where they propagate. This is the central argument of nonlinear silicon photonics. It is the aim of this review to describe the state-of-the-art in the field. Starting from the basic nonlinearities in a silicon waveguide or in optical resonator geometries, many phenomena and applications are described—including frequency generation, frequency conversion, frequency-comb generation, supercontinuum generation, soliton formation, temporal imaging and time lensing, Raman lasing, and comb spectroscopy. Emerging quantum photonics applications, such as entangled photon sources, heralded single-photon sources and integrated quantum photonic circuits are also addressed at the end of this review.

  2. Nonlinear fibre optics overview

    DEFF Research Database (Denmark)

    Travers, J. C.; Frosz, Michael Henoch; Dudley, J. M.

    2010-01-01

    , provides a background to the associated nonlinear optical processes, treats the generation mechanisms from continuous wave to femtosecond pulse pump regimes and highlights the diverse applications. A full discussion of numerical methods and comprehensive computer code are also provided, enabling readers...

  3. Nonlinear silicon photonics

    Science.gov (United States)

    Tsia, Kevin K.; Jalali, Bahram

    2010-05-01

    An intriguing optical property of silicon is that it exhibits a large third-order optical nonlinearity, with orders-ofmagnitude larger than that of silica glass in the telecommunication band. This allows efficient nonlinear optical interaction at relatively low power levels in a small footprint. Indeed, we have witnessed a stunning progress in harnessing the Raman and Kerr effects in silicon as the mechanisms for enabling chip-scale optical amplification, lasing, and wavelength conversion - functions that until recently were perceived to be beyond the reach of silicon. With all the continuous efforts developing novel techniques, nonlinear silicon photonics is expected to be able to reach even beyond the prior achievements. Instead of providing a comprehensive overview of this field, this manuscript highlights a number of new branches of nonlinear silicon photonics, which have not been fully recognized in the past. In particular, they are two-photon photovoltaic effect, mid-wave infrared (MWIR) silicon photonics, broadband Raman effects, inverse Raman scattering, and periodically-poled silicon (PePSi). These novel effects and techniques could create a new paradigm for silicon photonics and extend its utility beyond the traditionally anticipated applications.

  4. Is this scaling nonlinear?

    CERN Document Server

    Leitao, J C; Gerlach, M; Altmann, E G

    2016-01-01

    One of the most celebrated findings in complex systems in the last decade is that different indexes y (e.g., patents) scale nonlinearly with the population~x of the cities in which they appear, i.e., $y\\sim x^\\beta, \\beta \

  5. Nonlinear Gravitational Lagrangians revisited

    CERN Document Server

    Magnano, Guido

    2016-01-01

    The Legendre transformation method, applied in 1987 to deal with purely metric gravitational Lagrangians with nonlinear dependence on the Ricci tensor, is extended to metric-affine models and is shown to provide a concise and insightful comparison of the dynamical content of the two variational frameworks.

  6. Nonlinearities in Microwave Superconductivity

    OpenAIRE

    Ledenyov, Dimitri O.; Ledenyov, Viktor O.

    2012-01-01

    The research is focused on the modeling of nonlinear properties of High Temperature Superconducting (HTS) thin films, using Bardeen, Cooper, Schrieffer and Lumped Element Circuit theories, with purpose to enhance microwave power handling capabilities of microwave filters and optimize design of microwave circuits in micro- and nano- electronics.

  7. Nonlinear tsunami generation mechanism

    Directory of Open Access Journals (Sweden)

    M. A. Nosov

    2001-01-01

    Full Text Available The nonlinear mechanism of long gravitational surface water wave generation by high-frequency bottom oscillations in a water layer of constant depth is investigated analytically. The connection between the surface wave amplitude and the parameters of bottom oscillations and source length is investigated.

  8. Topics in Nonlinear Dynamics

    DEFF Research Database (Denmark)

    Mosekilde, Erik

    Through a significant number of detailed and realistic examples this book illustrates how the insights gained over the past couple of decades in the fields of nonlinear dynamics and chaos theory can be applied in practice. Aomng the topics considered are microbiological reaction systems, ecological...

  9. Terahertz semiconductor nonlinear optics

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias

    2013-01-01

    nonlinearity in doped semiconductors originates from the near-instantaneous heating of free electrons in the ponderomotive potential created by electric field of the THz pulse, leading to ultrafast increase of electron effective mass by intervalley scattering. Modification of effective mass in turn leads...

  10. Nonlinear Optical Terahertz Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Our approach is based on high-Q optical WGM resonators made with a nonlinear crystal. Such resonators have been demonstrated to dramatically enhance nonlinear...

  11. Phase retrieval using nonlinear diversity.

    Science.gov (United States)

    Lu, Chien-Hung; Barsi, Christopher; Williams, Matthew O; Kutz, J Nathan; Fleischer, Jason W

    2013-04-01

    We extend the Gerchberg-Saxton algorithm to phase retrieval in a nonlinear system. Using a tunable photorefractive crystal, we experimentally demonstrate the noninterferometric technique by reconstructing an unknown phase object from optical intensity measurements taken at different nonlinear strengths.

  12. Strong nonlinear oscillators analytical solutions

    CERN Document Server

    Cveticanin, Livija

    2017-01-01

    This book outlines an analytical solution procedure of the pure nonlinear oscillator system, offering a solution for free and forced vibrations of the one-degree-of-freedom strong nonlinear system with constant and time variable parameter. Includes exercises.

  13. Trends, Issues, and Gaps in Technology for Elementary Social Studies.

    Science.gov (United States)

    Nickell, Pat; Field, Sherry L.; Roach, Pamela S.

    2001-01-01

    Addresses the status of technology in elementary social studies. Reviews research on technology and elementary social studies, explores various examples of practice, discusses how preservice social studies methods textbooks treat the issue of using technology, and identifies beliefs held by elementary social studies teachers. (CMK)

  14. Preservice Elementary Teachers and the Fundamentals of Probability

    Science.gov (United States)

    Dollard, Clark

    2011-01-01

    This study examined how preservice elementary teachers think about situations involving probability. Twenty-four preservice elementary teachers who had not yet studied probability as part of their preservice elementary mathematics coursework were interviewed using a task-based interview. The participants' responses showed a wide variety of…

  15. Outliers: Elementary Teachers Who Actually Teach Social Studies

    Science.gov (United States)

    Anderson, Derek

    2014-01-01

    This mixed methods study identified six elementary teachers, who, despite the widespread marginalization of elementary social studies, spent considerable time on the subject. These six outliers from a sample of forty-six Michigan elementary teachers were interviewed, and their teaching was observed to better understand how and why they deviate…

  16. Architectural Survey of Pershing Elementary School, Fort Leonard Wood, Missouri

    Science.gov (United States)

    2013-08-01

    classroom needs flexibility.14 Lincoln Elementary School , located at Fort Campbell, Kentucky, was the first school ...resources management ; Pershing Elementary School ; historic buildings 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES...ER D C/ CE RL T R- 13 -1 1 Architectural Survey of Pershing Elementary School , Fort Leonard Wood, Missouri Co ns tr uc tio n En gi

  17. Elementary School Organization: Self-Contained and Departmentalized Classroom Structures.

    Science.gov (United States)

    Des Moines Public Schools, IA.

    Surveys were conducted to investigate contemporary thought regarding organizational practices at the elementary level, with particular attention to identifying the extent to which departmentalization was supported by research and actually employed in 24 elementary schools in the Midwest and in 41 Des Moines elementary schools. Four committees…

  18. Preservice Elementary Teachers and the Fundamentals of Probability

    Science.gov (United States)

    Dollard, Clark

    2011-01-01

    This study examined how preservice elementary teachers think about situations involving probability. Twenty-four preservice elementary teachers who had not yet studied probability as part of their preservice elementary mathematics coursework were interviewed using a task-based interview. The participants' responses showed a wide variety of…

  19. 43 CFR 17.220 - Preschool, elementary, and secondary education.

    Science.gov (United States)

    2010-10-01

    ... Handicap § 17.220 Preschool, elementary, and secondary education. This section applies to preschool, elementary, secondary, and adult education programs or activities that receive Federal financial assistance... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Preschool, elementary, and...

  20. Defect-controlled vortex generation in current-carrying narrow superconducting strips

    Science.gov (United States)

    Vodolazov, D. Yu; Ilin, K.; Merker, M.; Siegel, M.

    2016-02-01

    We experimentally study the effect of a single circular hole on the critical current I c of narrow superconducting strip with width W much smaller than Pearl penetration depth Λ. We found non-monotonous dependence of I c on the location of a hole across the strip and a weak dependence of I c on the radius of a hole in the case of a hole with ξ \\ll R\\ll W (ξ is a superconducting coherence length) which is placed in the center of strip. The observed effects are caused by competition of two mechanisms of destruction of superconductivity—the entrance of vortex via the edge of the strip and the nucleation of the vortex-antivortex pair near the hole. The mechanisms are clearly distinguishable by a difference in dependence of I c on weak magnetic field.

  1. A Study on the Thermal Effect of the Current-Carrying Capacity of Embedded Underground Cable

    Directory of Open Access Journals (Sweden)

    LI Dewen

    2012-10-01

    Full Text Available The current paper aims to study embedded underground cable and the effect of temperature that surrounds it. Determining the carrying capacity of the cable is important to predict the temperature changesin the embedded pipe. Simulating the temperature field and the laying environment according to the IEC standard enables the calculation of the carrying capacity of the buried region. According to the theoryof heat transfer, the embedded pipe tube model temperature field should be coupled with a numerical model. The domain and boundary conditions of the temperature field should also be determined using the 8.7/15kV YJV 400 cable. In conducting numerical calculation and analysis using the temperature field model, the two-dimensional temperature distribution of the emission control area should be determined. The experimental results show that the simulation isconsistent with the IEC standard. Furthermore, in identifying the cable ampacity, the different seasons and different cable rows should be taken into account using the finite element method. Finally, theappropriate choice of root and circuit numbers of the cable will improve the cable’s the carrying capacity.

  2. On the Behaviour of Current-Carrying Wire-Conductors and Bucking of a Column

    DEFF Research Database (Denmark)

    Ganji, S. S.; Barari, Amin; Fereidoon, A.

    2013-01-01

    -conductors and bucking of a column as well as their comparisons with the exact solutions are presented. Different specific parameters and initial values comprising the mass and stiffness are studied within the current research and excellent accuracy which is the most significant feature of the proposed solutions...

  3. Random phase approximation with second-order screened exchange for current-carrying atomic states

    Science.gov (United States)

    Zhu, Wuming; Zhang, Liang; Trickey, S. B.

    2016-12-01

    The direct random phase approximation (RPA) and RPA with second-order screened exchange (SOSEX) have been implemented with complex orbitals as a basis for treating open-shell atoms. Both RPA and RPA+SOSEX are natural implicit current density functionals because the paramagnetic current density implicitly is included through the use of complex orbitals. We confirm that inclusion of the SOSEX correction improves the total energy accuracy substantially compared to RPA, especially for smaller-Z atoms. Computational complexity makes post self-consistent-field (post-SCF) evaluation of RPA-type expressions commonplace, so orbital basis origins and properties become important. Sizable differences are found in correlation energies, total atomic energies, and ionization energies for RPA-type functionals evaluated in the post-SCF fashion with orbital sets obtained from different schemes. Reference orbitals from Kohn-Sham calculations with semi-local functionals are more suitable for RPA+SOSEX to generate accurate total energies, but reference orbitals from exact exchange (non-local) yield essentially energetically degenerate open-shell atom ground states. RPA+SOSEX correlation combined with exact exchange calculated from a hybrid reference orbital set (half the exchange calculated from exact-exchange orbitals, the other half of the exchange from orbitals optimized for the Perdew-Burke-Ernzerhof (PBE) exchange functional) gives the best overall performance. Numerical results show that the RPA-like functional with SOSEX correction can be used as a practical implicit current density functional when current effects should be included.

  4. Eddy current quality control of soldered current-carrying busbar splices of superconducting magnets

    CERN Document Server

    Kogan, L; Savary, F; Principe, R; Datskov, V; Rozenfel'd, E; Khudjakov, B

    2015-01-01

    The eddy current technique associated with a U-shaped transducer is studied for the quality control of soldered joints between superconducting busbars ('splices'). Two other quality control techniques, based on X-rays and direct measurement of the electrical resistance, are also studied for comparison. A comparative analysis of the advantages and disadvantages of these three methods in relation to the quality control of soldered superconducting busbar cables enclosed in copper shells is used for benchmarking. The results of inspections with the U-shaped eddy current transducer carried out on several sample joints presenting different types of soldering defects show the potential of this type of nondestructive (ND) quality control technique.

  5. Magnetic signature of current carrying edge localized modes filaments on the Joint European Torus tokamak

    DEFF Research Database (Denmark)

    Migliucci, P.; Naulin, Volker

    2010-01-01

    Fast magnetic pickup coils are used in forward modeling to match parameters in a simple edge localized mode (ELM) filament model. This novel method allows us to determine key parameters for the evolution of the ELM filaments, as effective mode number, radial and toroidal velocities, and average...

  6. Modelling and simulation of the ice melting process on a current-carrying conductor

    Energy Technology Data Exchange (ETDEWEB)

    Peter, Z.

    2006-07-01

    Mathematical models were developed to determine the current and energy requirements for thermal de-icing and ice prevention on overhead power transmission lines. The models were based on the Joule effect under various meteorological and current transmission conditions. The minimum current intensity required to inhibit ice formation on a single power line conductor was determined. Correction factors were then introduced for 3 specific aluminum conductors with steel reinforcement (ACSRs). Water runback on the conductor surface was considered as well as deviation of the water layer from the thermal equilibrium state. Model results were in good agreement with measurements taken in an icing research wind tunnel. The overall heat transfer coefficient (HTC) for stranded conductors was then assessed to complete the model. A computational model using finite differences was also developed to calculate the current and energy requirements for de-icing partially ice covered conductors. Joule heating by AC current and impulse current were the 2 heating techniques analyzed. Thermal conductivity of the ACSR conductor was also estimated. Experimentally validated analytical approaches were proposed to determine the shedding time and corresponding energy required to de-ice a completely ice covered conductor by heating with increased nominal AC current. It was concluded that ice accretion on a single power line can be prevented using the experimentally validated mathematical models that calculate the current and energy requirements of de-icing conductors.

  7. Electron heat transport in current carrying and currentless thermonuclear plasmas. Tokamaks and stellarators compared

    Energy Technology Data Exchange (ETDEWEB)

    Peters, M.

    1996-01-16

    In the first experiment the plasma current in the RTP tokamak is varied. Here the underlying idea was to check whether at a low plasma current, transport in the tokamak resembles transport in stellarators more than at higher currents. Secondly, experiments have been done to study the relation of the diffusivity {chi} to the temperature and its gradient in both W7-AS and RTP. In this case the underlying idea was to find the explanation for the phenomenon observed in both tokamaks and stellarators that the quality of the confinement degrades when more heating is applied. A possible explanation is that the diffusivity increases with the temperature or its gradient. Whereas in standard tokamak and stellarator experiments the temperature and its gradient are strongly correlated, a special capability of the plasma heating system of W7-AS and RTP can force them to decouple. (orig.).

  8. The Navier-Stokes equations an elementary functional analytic approach

    CERN Document Server

    Sohr, Hermann

    2001-01-01

    The primary objective of this monograph is to develop an elementary and self­ contained approach to the mathematical theory of a viscous incompressible fluid in a domain 0 of the Euclidean space ]Rn, described by the equations of Navier­ Stokes. The book is mainly directed to students familiar with basic functional analytic tools in Hilbert and Banach spaces. However, for readers' convenience, in the first two chapters we collect without proof some fundamental properties of Sobolev spaces, distributions, operators, etc. Another important objective is to formulate the theory for a completely general domain O. In particular, the theory applies to arbitrary unbounded, non-smooth domains. For this reason, in the nonlinear case, we have to restrict ourselves to space dimensions n = 2,3 that are also most significant from the physical point of view. For mathematical generality, we will develop the lin­ earized theory for all n 2 2. Although the functional-analytic approach developed here is, in principle, known ...

  9. Cubication of Conservative Nonlinear Oscillators

    Science.gov (United States)

    Belendez, Augusto; Alvarez, Mariela L.; Fernandez, Elena; Pascual, Immaculada

    2009-01-01

    A cubication procedure of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force, and this allows us to approximate the original nonlinear differential equation by a Duffing equation in which the coefficients for the linear…

  10. Terahertz Nonlinear Optics in Semiconductors

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias C.

    2013-01-01

    We demonstrate the nonlinear optical effects – selfphase modulation and saturable absorption of a single-cycle THz pulse in a semiconductor. Resulting from THz-induced modulation of Drude plasma, these nonlinear optical effects, in particular, lead to self-shortening and nonlinear spectral...

  11. Fault Detection for Nonlinear Systems

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.H.

    1998-01-01

    The paper describes a general method for designing fault detection and isolation (FDI) systems for nonlinear processes. For a rich class of nonlinear systems, a nonlinear FDI system can be designed using convex optimization procedures. The proposed method is a natural extension of methods based...

  12. Nonlinear electrostatic drift Kelvin-Helmholtz instability

    Science.gov (United States)

    Sharma, Avadhesh C.; Srivastava, Krishna M.

    1993-01-01

    Nonlinear analysis of electrostatic drift Kelvin-Helmholtz instability is performed. It is shown that the analysis leads to the propagation of the weakly nonlinear dispersive waves, and the nonlinear behavior is governed by the nonlinear Burger's equation.

  13. Elementary Teachers Negotiating Discourses in Writing Instruction

    Science.gov (United States)

    McCarthey, Sarah J.; Woodard, Rebecca; Kang, Grace

    2014-01-01

    Using Ivanic's (2004) framework, the study of 20 elementary teachers examines the relationships among teachers' beliefs about writing, their instructional practices, and contextual factors. While the district-adopted curriculum reflected specific discourses, teachers' beliefs and practices reflected a combination of discourses. The nature of the…

  14. Comprehending Elementary School Teachers' Classroom Management Approaches

    Science.gov (United States)

    Sahin, Ali E.

    2015-01-01

    This study intends to determine elementary school teachers' degree of classroom control, which constitutes the consistency in their classroom management and discipline-related behaviour. The major research question was as follows: Is the control approach adopted by teachers related to certain variables (gender, age, subject area, experience)? The…

  15. Preservice Elementary Teachers' Beliefs about Science Teaching

    Science.gov (United States)

    Yilmaz-Tuzun, Ozgul

    2008-01-01

    In this study, a Beliefs About Teaching (BAT) scale was created to examine preservice elementary science teachers' self-reported comfort level with both traditional and reform-based teaching methods, assessment techniques, classroom management techniques, and science content. Participants included 166 preservice teachers from three different US…

  16. Elementary Teacher Use of Formative Assessment

    Science.gov (United States)

    Cotton, Donna McLamb

    2013-01-01

    This dissertation was designed to examine elementary teacher use of formative assessment and the impact formative assessment may have on student achievement as measured by benchmark assessments. The study was conducted in a school district in northwestern North Carolina. The teachers in this study have had NCFALCON training in the use of formative…

  17. Freedom of Expression in Elementary School.

    Science.gov (United States)

    Zirkel, Perry A.

    2003-01-01

    Uses question and answer format to discuss scope of elementary students' First Amendment freedom of expression rights. For example, does the First Amendment prevent the disciplining of a sixth grader for writing a sexually inappropriate remark in another student's notebook? Answer: No. (Contains 13 references.) (PKP)

  18. Martha Lake Elementary School Post Occupancy Evaluation.

    Science.gov (United States)

    Washington Univ., Seattle. Center for Environment, Education and Design Studies.

    This post-occupancy evaluation of Martha Lake Elementary School in the Edmonds School District, Washington, was designed to answer questions in two areas: (1) "What aspects of the facility are effectively supporting learning and the current educational program? Conversely, which aspects, elements, or components of the facility appear to be…

  19. Transformational Leadership Behaviors in Elementary School Principals

    Science.gov (United States)

    Ergle, Barbara

    2012-01-01

    School leaders face high expectations from society for leadership effectiveness. While it is commonly accepted that leadership practices contribute to school excellence, specific behaviors of effective elementary principals in the local context were not well understood. The purpose of this mixed methods study was to investigate self-reported…

  20. Computer Assisted Assessment in Elementary Algebra

    OpenAIRE

    Bouhineau, Denis; Bronner, Alain; Chaachoua, Hamid; Mezerette, Sophie; Nicaud, Jean-François

    2005-01-01

    reviewed article for online journal available : http://mathstore.ac.uk/articles/maths-caa-series/nov2005/; Experiences and points of view from the APLUSIX project about Computer Assisted Assessment in Elementary Algebra (http://mathstore.ac.uk/articles/maths-caa-series/nov2005/)

  1. Suicide among Elementary School-Aged Children.

    Science.gov (United States)

    Nelson, Richard E; Crawford, Beth

    1990-01-01

    Questionnaires completed by approximately 125 counselors revealed contact with 187 students considering suicide during 1 academic year, 26 of whom had attempted suicide, and 1 of whom committed suicide. Critical concerns of elementary students identified by counselors included parent divorce, appearance/self-esteem, peer pressure, remarriage,…

  2. Cooperative Learning and Elementary Social Studies.

    Science.gov (United States)

    Guyton, Edith

    1991-01-01

    Argues that cooperative learning is useful in elementary social studies instruction. Identifies positive interdependence, student interaction, individual accountability for mastering material, and appropriate interpersonal and small group skills as essential elements of cooperative learning. Suggests that cooperative learning can help teach social…

  3. Chaos and fractals an elementary introduction

    CERN Document Server

    Feldman, David P

    2012-01-01

    For students with a background in elementary algebra, this text provides a vivid introduction to the key phenomena and ideas of chaos and fractals, including the butterfly effect, strange attractors, fractal dimensions, Julia sets and the Mandelbrot set, power laws, and cellular automata.

  4. Minority (Ethnic) Studies in the Elementary Grades.

    Science.gov (United States)

    Schwartz, Lita Linzer

    The paper offers recommendations for an ethnic studies curriculum at the elementary school level which would be interdisciplinary in nature and integrate the basic skills of reading, writing, and critical thinking. In the social studies, for example, concepts of cultural diversity and universality can be presented in simple form in the early…

  5. Elementary Character Education: Local Perspectives, Echoed Voices.

    Science.gov (United States)

    Nickell, Pat; Field, Sherry L.

    2001-01-01

    Presents information based on a yearlong study of character education in an elementary school that was implementing "Kids with Character." Offers an analysis of the responses by students, teachers, and parents about character, development of character, and the program. Indicates that contemporary character education programs are similar to…

  6. Programed Instruction in Elementary Algebra: An Experiment

    Science.gov (United States)

    Lial, Margaret L.

    1970-01-01

    Report of an experiment which investigated the use of a programed elementary algebra text as a teaching method. The method was evaluated on the basis of student evaluation of the course and the percentage of students achieving a grade of C or better. Results indicated that the use of programed texts was superior to the traditional approach using…

  7. Fair Partitions of Polygons: An Elementary Introduction

    Indian Academy of Sciences (India)

    R Nandakumar; N Ramana Rao

    2012-08-01

    We introduce the question: Given a positive integer , can any 2D convex polygonal region be partitioned into convex pieces such that all pieces have the same area and the same perimeter? The answer to this question is easily `yes’ for =2. We give an elementary proof that the answer is `yes’ for =4 and generalize it to higher powers of 2.

  8. Geotechnical Engineering in US Elementary Schools

    Science.gov (United States)

    Suescun-Florez, Eduardo; Iskander, Magued; Kapila, Vikram; Cain, Ryan

    2013-01-01

    This paper reports on the results of several geotechnical engineering-related science activities conducted with elementary-school students. Activities presented include soil permeability, contact stress, soil stratigraphy, shallow and deep foundations, and erosion in rivers. The permeability activity employed the LEGO NXT platform for data…

  9. Variables Affecting Change at Laguna Elementary School.

    Science.gov (United States)

    Lockart, Barbetta L.

    After nearly 14 years of non-Indian administration, Laguna Elementary School (LES) has acquired a principal and a teacher supervisor who are not merely Indian, but of the Laguna Tribe itself, making LES the only school in the Southern Pueblos Agency with Tribal members as administrators. At first glance the situation is ideal, but there are…

  10. Programed Instruction in Elementary Algebra: An Experiment

    Science.gov (United States)

    Lial, Margaret L.

    1970-01-01

    Report of an experiment which investigated the use of a programed elementary algebra text as a teaching method. The method was evaluated on the basis of student evaluation of the course and the percentage of students achieving a grade of C or better. Results indicated that the use of programed texts was superior to the traditional approach using…

  11. Fifth Grade Elementary Students' Conceptions of Earthquakes

    Science.gov (United States)

    Savasci, Funda; Uluduz, Hatice

    2013-01-01

    This study intends to investigate the fifth grade students' conceptions of earthquakes. Twenty two grade 5 students (11-12 years old) from five different elementary schools in Istanbul voluntarily participated in the study. Data were collected from semi-structured interviews with each participant. Six interview questions were designed by…

  12. Elementary Teachers' Tolerance of Problem Behaviors.

    Science.gov (United States)

    Safran, Stephen P.; Safran, Joan S.

    1984-01-01

    A total of 46 teachers rated observable mild-to-moderate school-related problem behaviors in order to identify aspects of teacher tolerance specific to the elementary classroom. Findings indicated that behaviors least tolerated are other-directed or disruptive; self- or teacher-directed behaviors elicited less negative ratings. (RH)

  13. Geotechnical Engineering in US Elementary Schools

    Science.gov (United States)

    Suescun-Florez, Eduardo; Iskander, Magued; Kapila, Vikram; Cain, Ryan

    2013-01-01

    This paper reports on the results of several geotechnical engineering-related science activities conducted with elementary-school students. Activities presented include soil permeability, contact stress, soil stratigraphy, shallow and deep foundations, and erosion in rivers. The permeability activity employed the LEGO NXT platform for data…

  14. Tlingit Moon & Tide Teaching Resource: Elementary Level.

    Science.gov (United States)

    Garza, Dolly

    This book brings Alaskan Native understanding of science and ecology to the elementary classroom by showing teachers how to present local and ecosystem knowledge held by long-time inhabitants of southeast Alaska. The goal is to increase the self-esteem of Native students who traditionally perform low in science and to introduce non-Native students…

  15. Indigenous Languages and Mathematics in Elementary Schools

    Science.gov (United States)

    Edmonds-Wathen, Cris; Owens, Kay; Sakopa, Priscilla; Bino, Vagi

    2014-01-01

    Indigenous languages are used for instruction in elementary schools in Papua New Guinea, but teachers have generally received their own education in English. The challenges of identifying terminology to use in mathematics include many-to-one correspondences between English and the vernacular languages, and different grammatical structures.…

  16. Elementary Functions, Student's Text, Unit 21.

    Science.gov (United States)

    Allen, Frank B.; And Others

    Unit 21 in the SMSG secondary school mathematics series is a student text covering the following topics in elementary functions: functions, polynomial functions, tangents to graphs of polynomial functions, exponential and logarithmic functions, and circular functions. Appendices discuss set notation, mathematical induction, significance of…

  17. Ten Basic Materials for the Elementary Classroom.

    Science.gov (United States)

    Thomas, Marcine

    1982-01-01

    A resource specialist discusses materials that are useful with hearing impaired elementary students. Materials considered include attribute blocks, globes, pictures showing facial expressions, sequence cards, cuisenaire rods, and interesting books. Names and addresses of 13 publishers and distributors are provided. (CL)

  18. Grace and Courtesy in the Elementary Community

    Science.gov (United States)

    Huneke-Stone, Elise

    2015-01-01

    Don't be fooled by Elise Huneke-Stone's disarming beginning where she implies that grace and courtesy is not normally associated with the elementary. She goes on to elaborate that grace and courtesy is indeed everywhere: in project-based learning, understanding of moral precepts, social and intellectual independence, in the utilization of empathy,…

  19. Elementary Magnet School Students' Interracial Interaction Choices.

    Science.gov (United States)

    Dickinson, Gerald B.; Holifield, Mitchell L.; Holifield, Glenda; Creer, Donna Grady

    2000-01-01

    Investigated elementary students' interracial interaction preferences in four desegregated, urban magnet schools. Data from a sociogram of students' working, playing, and sitting choices indicated that black students were less willing than white students to interact. Racial considerations were more pronounced among girls. There was no trend toward…

  20. Theoretical Studies in Elementary Particle Physics

    Energy Technology Data Exchange (ETDEWEB)

    Collins, John C.; Roiban, Radu S

    2013-04-01

    This final report summarizes work at Penn State University from June 1, 1990 to April 30, 2012. The work was in theoretical elementary particle physics. Many new results in perturbative QCD, in string theory, and in related areas were obtained, with a substantial impact on the experimental program.

  1. Learning Leadership Skills in Elementary School

    Science.gov (United States)

    Bowman, Richard F.

    2014-01-01

    Leadership is everyone's responsibility-even first graders. The most important contribution that any educator can make in an era of unrelenting change is identifying and developing aspiring leaders. Elementary school teachers can embed leadership development opportunities into the classroom to foster leadership dispositions and skills…

  2. Conferenza internazionale di Siena sulle particelle elementari

    CERN Multimedia

    1964-01-01

    Last year the editor of CERN Courier was privileged to be able to attend the Sienna international conference on elementary particles, held in the historic Italian city at the beginning of October. The following article is a personal recollection of the conference activities, both formal and informal, and of the physics that was discussed there.

  3. Native Americans: An Elementary Art Unit.

    Science.gov (United States)

    Brown, Pat

    This elementary art unit, which exposes students to the art and culture of American Indian tribes, is divided into four sections. Each section deals with a geographical area and a tribe or tribes within that area. Background information precedes instructions for art projects related to specific tribes. The influence of the environment on culture…

  4. Bullying in Elementary School: An American Perspective

    Science.gov (United States)

    Conn, Kathleen

    2013-01-01

    Bullying in elementary schools is a recognized and widespread occurrence that threatens to rob children of their childhood. Part I of this commentary describes existing scientifically-based research on the nature, extent and effects of the phenomenon on children in United States schools. Part II analyzes the effectiveness of bullying prevention…

  5. Helping Elementary Teachers Understand Children and Divorce.

    Science.gov (United States)

    Hrymak, Marilyn J.; Smart, Laura S.

    1984-01-01

    Describes a workshop designed to help elementary teachers understand the recent literature on the effects of divorce on children and help the children through the crisis. Indicates that secondary home economics teachers may have to deal with students who have not adjusted to divorce. (JOW)

  6. Transforming Elementary Statistics To Enhance Student Learning.

    Science.gov (United States)

    Lane, Jill L.; Aleksic, Maja

    Undergraduate students often leave statistics courses not fully understanding how to apply statistical concepts (M. Bonsangue, 1994). In order to enhance student learning and improve the understanding and application of statistical concepts, an elementary statistics course was transformed from a lecture-based course into one that integrates…

  7. Safety in the Elementary Science Classroom.

    Science.gov (United States)

    National Science Teachers Association, Arlington, VA.

    This guide gives elementary school teachers suggestions for providing a safe environment for their students and covers general safety concerns in the science classroom. Information is printed in a flip chart format for easy reference. Safety areas covered include: (1) In Case of Accident; (2) Eye Protection; (3) Plants in the Classroom; (4) First…

  8. Sports profile in public elementary school

    DEFF Research Database (Denmark)

    Warren Pedersen, Lise; Trangbæk, Else

    2012-01-01

    In 2005, Copenhagen municipality decided to develop and implement a sport and movement profile at a local elementary school. The overall development is discussed as are specific results and consequences of the decision. The role of physical education and teachers in relation to a health discourse...

  9. Supporting reflective web searching in elementary schools

    NARCIS (Netherlands)

    Vries, de Bregje; Meij, van der Hans; Lazonder, Ard W.

    2008-01-01

    In this contribution, two design experiments are presented in which reflective web searching is implemented in six elementary classrooms. Reflective web searching is viewed to comprise three steps: (1) develop ownership over search questions, (2) interpret and personalize web content, and (3) adapt

  10. Northrop Frye in the Elementary Classroom

    Science.gov (United States)

    Sloan, Glenna

    2009-01-01

    Northrop Frye (1912-1991) was one of the leading literary theorists of his day, and this article shows the ways in which his theories continue to be relevant for both the field of literary criticism and elementary classroom education today. The author, an eminent scholar in the field of children's literature in her own right and a student of…

  11. Ripples: A Big Sweep Elementary Activity Guide.

    Science.gov (United States)

    Burgess, Carla B., Ed.

    Littering is a careless act indicating lack of respect for the environment, other people, and wildlife. Through education people can learn the consequences of littering and how to stop doing it. This book, designed for elementary children, presents a collection of 16 activities, ideas and resources concerning litter in the aquatic and marine…

  12. Elementary Health Education Guide to Better Health.

    Science.gov (United States)

    Washington Office of the State Superintendent of Public Instruction, Olympia.

    This curriculum guide for the elementary school portion of a K-12 health education program contains notes on eleven areas: Alcohol, Anatomy and Physiology, Community Health, Consumer Health, Dental Health, Disease Control, Family Health, Heredity and Environment, Mental Health, Nutrition, and Safety Education. The notes on each area contain a…

  13. Teaching Elementary Particle Physics: Part I

    Science.gov (United States)

    Hobson, Art

    2011-01-01

    I'll outline suggestions for teaching elementary particle physics, often called "high energy physics," in high school or introductory college courses for non-scientists or scientists. Some presentations of this topic simply list the various particles along with their properties, with little overarching structure. Such a laundry list approach is a…

  14. What Do Elementary Students Know about Insects?

    Science.gov (United States)

    Barrow, Lloyd H.

    2002-01-01

    Presents an interview-based study of (n=56) elementary school students. Determines students' understanding about insect characteristics, life cycles, environmental conditions, and impact on humans. Suggests building units of instruction based on students' personal questions about insects. (Contains 16 references.) (Author/YDS)

  15. Critical Literacy in Elementary Education in Cambodia

    Science.gov (United States)

    In, Vichea

    2012-01-01

    This study focuses on a quest for insights into the introduction and negotiation of critical literacy in elementary education in Cambodia, whose recent past was scarred by devastating conflicts and wars. In this study, critical education is seen as a key to avoiding the reproduction of an unwanted past and minimizing social injustice in Cambodia.…

  16. Tips for Teaching Math to Elementary Students

    Science.gov (United States)

    Scarpello, Gary

    2010-01-01

    Since most elementary school teachers do not hold a degree in mathematics, teaching math may be a daunting task for some. Following are a few techniques to help make teaching and learning math easier and less stressful. First, know that math is a difficult subject to teach--even for math teachers. The subject matter itself is challenging. Second,…

  17. Preservice Elementary Teachers' Understanding of Logical Inference

    Science.gov (United States)

    Hauk, Shandy; Judd, April Brown; Tsay, Jenq Jong; Barzilai, Harel; Austin, Homer

    2009-01-01

    This article reports on the logical reasoning efforts of five prospective elementary school teachers as they responded to interview prompts involving nonsense, natural, and mathematical representations of conditional statements. The interview participants evinced various levels of reliance on personal relevance, linguistic contextualization, and…

  18. Social Studies in the Japanese Elementary School.

    Science.gov (United States)

    Thomas, Paul F.

    1985-01-01

    The most striking feature of the Japanese social studies curriculum at the elementary level is its role as the instructor of Japanese national values and attitudes. The social studies curriculum has gone through four major revisions since World War II. In the most recent revision, in the early 1980's, the focus has been on instituting new teaching…

  19. Elementary Mathematics, Grades 1-6.

    Science.gov (United States)

    Nederland Independent School District, TX.

    GRADES OR AGES: Grades 1-6. SUBJECT MATTER: Elementary math. ORGANIZATION AND PHYSICAL APPEARANCE: Introductory material focuses on the philosophy and objectives of instructional material. The guide is divided into six units covering grades 1-6. Each unit presents the general goals, materials needed, minimum program, skills to be developed,…

  20. Nepal: Vocational Educator's Role in Elementary Education

    Science.gov (United States)

    Stitt, Thomas R.

    1974-01-01

    The innovative vocational education program of the elementary grades in the developing country of Nepal focuses on "self-help" within the "practical arts" (agriculture, trade and industrial, and home science fields) and emphasizes application of subject matter to students' daily lives, integration of skills into the curriculum, and occupational…

  1. Art Teaching: Elementary through Middle School

    Science.gov (United States)

    Szekely, George; Bucknam, Julie Alsip

    2011-01-01

    "Art Teaching" speaks to a new generation of art teachers in a changing society and fresh art world. Comprehensive and up-to-date, it presents fundamental theories, principles, creative approaches, and resources for art teaching in elementary through middle-school. Key sections focus on how children make art, why they make art, the unique…

  2. Solution techniques for elementary partial differential equations

    CERN Document Server

    Constanda, Christian

    2012-01-01

    Incorporating a number of enhancements, Solution Techniques for Elementary Partial Differential Equations, Second Edition presents some of the most important and widely used methods for solving partial differential equations (PDEs). The techniques covered include separation of variables, method of characteristics, eigenfunction expansion, Fourier and Laplace transformations, Green’s functions, perturbation methods, and asymptotic analysis.

  3. Fifth Grade Elementary Students' Conceptions of Earthquakes

    Science.gov (United States)

    Savasci, Funda; Uluduz, Hatice

    2013-01-01

    This study intends to investigate the fifth grade students' conceptions of earthquakes. Twenty two grade 5 students (11-12 years old) from five different elementary schools in Istanbul voluntarily participated in the study. Data were collected from semi-structured interviews with each participant. Six interview questions were designed by…

  4. Improvisational Practices in Elementary General Music Classrooms

    Science.gov (United States)

    Gruenhagen, Lisa M.; Whitcomb, Rachel

    2014-01-01

    Despite historic and ongoing support for the inclusion of improvisation in the elementary general music curriculum, music educators consistently report challenges with implementation of improvisational activities in their classes. This study was designed to examine (a) the extent to which improvisational activities were occurring in the…

  5. Cooperative Learning and Elementary Social Studies.

    Science.gov (United States)

    Guyton, Edith

    1991-01-01

    Argues that cooperative learning is useful in elementary social studies instruction. Identifies positive interdependence, student interaction, individual accountability for mastering material, and appropriate interpersonal and small group skills as essential elements of cooperative learning. Suggests that cooperative learning can help teach social…

  6. Elementary Mathematics Teachers' Knowledge of Equity Pedagogy

    Science.gov (United States)

    Jackson, Christa

    2013-01-01

    Currently, mathematics instruction in U.S. classrooms is far from achieving equity for African American students. This qualitative study reports the results of eight successful elementary mathematics teachers' knowledge of equity pedagogy, specifically their knowledge of culturally relevant pedagogy, cultural competence, and critical…

  7. Contested Spaces of a "Failing" Elementary School

    Science.gov (United States)

    Kawai, Roi; Serriere, Stephanie; Mitra, Dana

    2014-01-01

    Amid the recent proliferation of teacher-led movements resisting high-stakes testing across the United States, the authors identify how a "failing" elementary school reclaimed local discourse by taking political action against top-down measures. Framed as competing modes of school reform, the authors offer the sociocultural framework of…

  8. Public Montessori Elementary Schools: A Delicate Balance

    Science.gov (United States)

    Murray, Angela; Peyton, Vicki

    2008-01-01

    Public Montessori elementary schools have two challenges: They strive to achieve a child-centered Montessori environment and must also address the demands of state and federal requirements developed for more traditional educational settings. This study analyzes how schools were operating on both fronts. On the one hand, the study measured the…

  9. Scripted Collaborative Drawing in Elementary Science Education

    Science.gov (United States)

    van Dijk, Alieke M.; Gijlers, Hannie; Weinberger, Armin

    2014-01-01

    Creating graphical representations can foster knowledge gains on science topics in elementary school students by promoting active integration and translation of new information. Collaborating on joint representations may encourage children to discuss and elaborate their knowledge. To foster productive interactions, children may greatly benefit…

  10. Elementary Mathematics Teachers' Knowledge of Equity Pedagogy

    Science.gov (United States)

    Jackson, Christa

    2013-01-01

    Currently, mathematics instruction in U.S. classrooms is far from achieving equity for African American students. This qualitative study reports the results of eight successful elementary mathematics teachers' knowledge of equity pedagogy, specifically their knowledge of culturally relevant pedagogy, cultural competence, and critical…

  11. Ready, Set, Respect! GLSEN's Elementary School Toolkit

    Science.gov (United States)

    Gay, Lesbian and Straight Education Network (GLSEN), 2012

    2012-01-01

    "Ready, Set, Respect!" provides a set of tools to help elementary school educators ensure that all students feel safe and respected and develop respectful attitudes and behaviors. It is not a program to be followed but instead is designed to help educators prepare themselves for teaching about and modeling respect. The toolkit responds to…

  12. Nathaniel Hawthorne Elementary School: San Antonio, Texas.

    Science.gov (United States)

    American Educator, 1997

    1997-01-01

    Discusses the successful use of Core Knowledge Curriculum in one inner-city elementary school in San Antonio (Texas) that had previously reflected low student achievement, inconsistent attendance, and student behavioral problems. Improvements in these conditions as revealed through teacher observations are highlighted. (GR)

  13. Teaching about Japan in the Elementary School.

    Science.gov (United States)

    Cogan, John J.

    1981-01-01

    Focuses on ideas for teaching about Japan which elementary school classroom teachers can use to supplement a textbook unit on Japan. Suggestions are intended to allow for reflection by students on their own culture, as well as the culture of Japan. Topics are children's perceptions of Japan and the Japanese, developing a geographical perspective,…

  14. Integrating Children's Literature in Elementary Mathematics

    Science.gov (United States)

    Thomas, Lynsey; Feng, Jay

    2015-01-01

    The purpose of this professional development project was to train teachers in using children's literature for math instruction and to also examine its effect on student math learning at an elementary school. Teachers were taught how to use children's literature to instruct and enhance their math curriculum through the use of literature pieces,…

  15. Preparing Elementary Mathematics-Science Teaching Specialists.

    Science.gov (United States)

    Miller, L. Diane

    1992-01-01

    Describes a professional development program to train math/science specialists for the upper elementary school grades. Using results from an interest survey, 30 teachers were chosen to participate in a 3-year program to become math/science specialists. Presents the teaching model used and the advantages for teachers and students in having subject…

  16. Enhancing science education in the elementary schools

    CERN Document Server

    Cole, M W; Cole, Milton W.; Zembal-Saul, Carla

    2002-01-01

    This article describes some collaborative activities of the authors, aimed at improving science education in elementary schools. These include curriculum enhancement, development of new apparatus (a wind tunnel), science-education web site contributions and production of a film about the physics of flight. The output of these projects is intended to be generally accessible or reproducible.

  17. Bringing the Science of Climate Change to Elementary Students with new Classroom Activities from Elementary GLOBE

    Science.gov (United States)

    Gardiner, L. S.; Hatheway, B.; Taylor, J.; Chambers, L. H.; Stanitski, D.

    2016-12-01

    To address the dearth of climate education resources at the elementary level, we have developed a new module of Elementary GLOBE to showcase the science of climate change for young learners. Elementary GLOBE builds K-4 student understanding of the science concepts and the practices of science research. At the heart of each Elementary GLOBE module is a fiction storybook, describing how three kids investigate a science question. Accompanying classroom activities allow students to explore the science concepts in the book in more depth and in a context appropriate for young learners. The book for the Elementary GLOBE climate module, "What in the World Is Happening to Our Climate?," is the account of an adventure to explore climate change, how it is affecting melting glacial ice and sea level rise, and how climate change is a problem that can be solved. Three hands-on activities, which will be presented at this session, allow students to explore the topics in greater depth including differences between weather and climate, how sea level rise affects coastal areas, and how they can shrink their carbon footprint to help address recent climate change. Each activity includes instructions for teachers, background information, and activity sheets for students, and is aligned to the Next Generation Science Standards and Common Core Math and Language Arts Standards. The storybook and activities were field tested in classrooms and reviewed by climate and Earth system scientists as well as elementary education and climate education specialists and educators to ensure scientific accuracy and clear explanations, and that the resources are age appropriate and reflect the needs of the climate education community. Other Elementary GLOBE modules include the science of seasonal change, water, soil, clouds, aerosols, and Earth as a system. All Elementary GLOBE educational resources are freely available online (www.globe.gov/elementaryglobe).

  18. Optothermal nonlinearity of silica aerogel

    CERN Document Server

    Braidotti, Maria Chiara; Fleming, Adam; Samuels, Michiel C; Di Falco, Andrea; Conti, Claudio

    2016-01-01

    We report on the characterization of silica aerogel thermal optical nonlinearity, obtained by z-scan technique. The results show that typical silica aerogels have nonlinear optical coefficient similar to that of glass $(\\simeq 10^{-12} $m$^2/$W), with negligible optical nonlinear absorption. The non\\-li\\-near coefficient can be increased to values in the range of $10^{-10} $m$^2/$W by embedding an absorbing dye in the aerogel. This value is one order of magnitude higher than that observed in the pure dye and in typical highly nonlinear materials like liquid crystals.

  19. Essentials of nonlinear optics

    CERN Document Server

    Murti, Y V G S

    2014-01-01

    Current literature on Nonlinear Optics varies widely in terms of content, style, and coverage of specific topics, relative emphasis of areas and the depth of treatment. While most of these books are excellent resources for the researchers, there is a strong need for books appropriate for presenting the subject at the undergraduate or postgraduate levels in Universities. The need for such a book to serve as a textbook at the level of the bachelors and masters courses was felt by the authors while teaching courses on nonlinear optics to students of both science and engineering during the past two decades. This book has emerged from an attempt to address the requirement of presenting the subject at college level. A one-semester course covering the essentials can effectively be designed based on this.

  20. Nonlinear metamaterials for holography

    Science.gov (United States)

    Almeida, Euclides; Bitton, Ora; Prior, Yehiam

    2016-08-01

    A hologram is an optical element storing phase and possibly amplitude information enabling the reconstruction of a three-dimensional image of an object by illumination and scattering of a coherent beam of light, and the image is generated at the same wavelength as the input laser beam. In recent years, it was shown that information can be stored in nanometric antennas giving rise to ultrathin components. Here we demonstrate nonlinear multilayer metamaterial holograms. A background free image is formed at a new frequency--the third harmonic of the illuminating beam. Using e-beam lithography of multilayer plasmonic nanoantennas, we fabricate polarization-sensitive nonlinear elements such as blazed gratings, lenses and other computer-generated holograms. These holograms are analysed and prospects for future device applications are discussed.

  1. Nonlinear metamaterials for holography

    Science.gov (United States)

    Almeida, Euclides; Bitton, Ora

    2016-01-01

    A hologram is an optical element storing phase and possibly amplitude information enabling the reconstruction of a three-dimensional image of an object by illumination and scattering of a coherent beam of light, and the image is generated at the same wavelength as the input laser beam. In recent years, it was shown that information can be stored in nanometric antennas giving rise to ultrathin components. Here we demonstrate nonlinear multilayer metamaterial holograms. A background free image is formed at a new frequency—the third harmonic of the illuminating beam. Using e-beam lithography of multilayer plasmonic nanoantennas, we fabricate polarization-sensitive nonlinear elements such as blazed gratings, lenses and other computer-generated holograms. These holograms are analysed and prospects for future device applications are discussed. PMID:27545581

  2. Nonlinear data assimilation

    CERN Document Server

    Van Leeuwen, Peter Jan; Reich, Sebastian

    2015-01-01

    This book contains two review articles on nonlinear data assimilation that deal with closely related topics but were written and can be read independently. Both contributions focus on so-called particle filters. The first contribution by Jan van Leeuwen focuses on the potential of proposal densities. It discusses the issues with present-day particle filters and explorers new ideas for proposal densities to solve them, converging to particle filters that work well in systems of any dimension, closing the contribution with a high-dimensional example. The second contribution by Cheng and Reich discusses a unified framework for ensemble-transform particle filters. This allows one to bridge successful ensemble Kalman filters with fully nonlinear particle filters, and allows a proper introduction of localization in particle filters, which has been lacking up to now.

  3. Nonlinearity without Superluminality

    CERN Document Server

    Kent, A

    2002-01-01

    Quantum theory is compatible with special relativity. In particular, though measurements on entangled systems are correlated in a way that cannot be reproduced by local hidden variables, they cannot be used for superluminal signalling. As Gisin and Polchinski first pointed out, this is not true for general nonlinear modifications of the Schroedinger equation. Excluding superluminal signalling has thus been taken to rule out most nonlinear versions of quantum theory. The no superluminal signalling constraint has also been used for alternative derivations of the optimal fidelities attainable for imperfect quantum cloning and other operations. These results apply to theories satisfying the rule that their predictions for widely separated and slowly moving entangled systems can be approximated by non-relativistic equations of motion with respect to a preferred time coordinate. This paper describes a natural way in which this rule might fail to hold. In particular, it is shown that quantum readout devices which di...

  4. Monte Carlo and nonlinearities

    CERN Document Server

    Dauchet, Jérémi; Blanco, Stéphane; Caliot, Cyril; Charon, Julien; Coustet, Christophe; Hafi, Mouna El; Eymet, Vincent; Farges, Olivier; Forest, Vincent; Fournier, Richard; Galtier, Mathieu; Gautrais, Jacques; Khuong, Anaïs; Pelissier, Lionel; Piaud, Benjamin; Roger, Maxime; Terrée, Guillaume; Weitz, Sebastian

    2016-01-01

    The Monte Carlo method is widely used to numerically predict systems behaviour. However, its powerful incremental design assumes a strong premise which has severely limited application so far: the estimation process must combine linearly over dimensions. Here we show that this premise can be alleviated by projecting nonlinearities on a polynomial basis and increasing the configuration-space dimension. Considering phytoplankton growth in light-limited environments, radiative transfer in planetary atmospheres, electromagnetic scattering by particles and concentrated-solar-power-plant productions, we prove the real world usability of this advance on four test-cases that were so far regarded as impracticable by Monte Carlo approaches. We also illustrate an outstanding feature of our method when applied to sharp problems with interacting particles: handling rare events is now straightforward. Overall, our extension preserves the features that made the method popular: addressing nonlinearities does not compromise o...

  5. Nonlinear Photonics 2014: introduction.

    Science.gov (United States)

    Akhmediev, N; Kartashov, Yaroslav

    2015-01-12

    International Conference "Nonlinear Photonics-2014" took place in Barcelona, Spain on July 27-31, 2014. It was a part of the "Advanced Photonics Congress" which is becoming a traditional notable event in the world of photonics. The current focus issue of Optics Express contains contributions from the participants of the Conference and the Congress. The articles in this focus issue by no means represent the total number of the congress contributions (around 400). However, it demonstrates wide range of topics covered at the event. The next conference of this series is to be held in 2016 in Australia, which is the home of many researchers working in the field of photonics in general and nonlinear photonics in particular.

  6. Nonlinear fractional relaxation

    Indian Academy of Sciences (India)

    A Tofighi

    2012-04-01

    We define a nonlinear model for fractional relaxation phenomena. We use -expansion method to analyse this model. By studying the fundamental solutions of this model we find that when → 0 the model exhibits a fast decay rate and when → ∞ the model exhibits a power-law decay. By analysing the frequency response we find a logarithmic enhancement for the relative ratio of susceptibility.

  7. -Deformed nonlinear maps

    Indian Academy of Sciences (India)

    Ramaswamy Jaganathan; Sudeshna Sinha

    2005-03-01

    Motivated by studies on -deformed physical systems related to quantum group structures, and by the elements of Tsallis statistical mechanics, the concept of -deformed nonlinear maps is introduced. As a specific example, a -deformation procedure is applied to the logistic map. Compared to the canonical logistic map, the resulting family of -logistic maps is shown to have a wider spectrum of interesting behaviours, including the co-existence of attractors – a phenomenon rare in one-dimensional maps.

  8. Controllability of nonlinear systems.

    Science.gov (United States)

    Sussmann, H. J.; Jurdjevic, V.

    1972-01-01

    Discussion of the controllability of nonlinear systems described by the equation dx/dt - F(x,u). Concepts formulated by Chow (1939) and Lobry (1970) are applied to establish criteria for F and its derivatives to obtain qualitative information on sets which can be obtained from x which denotes a variable of state in an arbitrary, real, analytical manifold. It is shown that controllability implies strong accessibility for a large class of manifolds including Euclidean spaces.-

  9. Stochastic Nonlinear Aeroelasticity

    Science.gov (United States)

    2009-01-01

    STOCHASTIC NONLINEAR AEROELASTICITY 5a. CONTRACT NUMBER In- house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 0601102 6. AUTHOR(S) Philip S...ABSTRACT This report documents the culmination of in- house work in the area of uncertainty quantification and probabilistic techniques for... coff U∞ cs ea lw cw Figure 6: Wing and store geometry (left), wing box structural model (middle), flutter distribution (right

  10. Nonlinear Control Systems

    Science.gov (United States)

    2007-03-01

    IEEE Transactions on Automatic Control , AC- 48, pp. 1712-1723, (2003). [14] C.I. Byrnes, A. Isidori...Nonlinear internal models for output regulation,” IEEE Transactions on Automatic Control , AC-49, pp. 2244-2247, (2004). [15] C.I. Byrnes, F. Celani, A...approach,” IEEE Transactions on Automatic Control , 48 (Dec. 2003), 2172–2190. 2. C. I. Byrnes, “Differential Forms and Dynamical Systems,” to appear

  11. Filamentation with nonlinear Bessel vortices.

    Science.gov (United States)

    Jukna, V; Milián, C; Xie, C; Itina, T; Dudley, J; Courvoisier, F; Couairon, A

    2014-10-20

    We present a new type of ring-shaped filaments featured by stationary nonlinear high-order Bessel solutions to the laser beam propagation equation. Two different regimes are identified by direct numerical simulations of the nonlinear propagation of axicon focused Gaussian beams carrying helicity in a Kerr medium with multiphoton absorption: the stable nonlinear propagation regime corresponds to a slow beam reshaping into one of the stationary nonlinear high-order Bessel solutions, called nonlinear Bessel vortices. The region of existence of nonlinear Bessel vortices is found semi-analytically. The influence of the Kerr nonlinearity and nonlinear losses on the beam shape is presented. Direct numerical simulations highlight the role of attractors played by nonlinear Bessel vortices in the stable propagation regime. Large input powers or small cone angles lead to the unstable propagation regime where nonlinear Bessel vortices break up into an helical multiple filament pattern or a more irregular structure. Nonlinear Bessel vortices are shown to be sufficiently intense to generate a ring-shaped filamentary ionized channel in the medium which is foreseen as opening the way to novel applications in laser material processing of transparent dielectrics.

  12. Strongly nonlinear oscillators analytical solutions

    CERN Document Server

    Cveticanin, Livija

    2014-01-01

    This book provides the presentation of the motion of pure nonlinear oscillatory systems and various solution procedures which give the approximate solutions of the strong nonlinear oscillator equations. The book presents the original author’s method for the analytical solution procedure of the pure nonlinear oscillator system. After an introduction, the physical explanation of the pure nonlinearity and of the pure nonlinear oscillator is given. The analytical solution for free and forced vibrations of the one-degree-of-freedom strong nonlinear system with constant and time variable parameter is considered. Special attention is given to the one and two mass oscillatory systems with two-degrees-of-freedom. The criteria for the deterministic chaos in ideal and non-ideal pure nonlinear oscillators are derived analytically. The method for suppressing chaos is developed. Important problems are discussed in didactic exercises. The book is self-consistent and suitable as a textbook for students and also for profess...

  13. Quantum well nonlinear microcavities

    Science.gov (United States)

    Oudar, J. L.; Kuszelewicz, R.; Sfez, B.; Pellat, D.; Azoulay, R.

    We report on recent progress in reducing the power threshold of all-optical bistable quantum well vertical microcavities. Significant improvements are achieved through an increase of the cavity finesse, together with a reduction of the device active layer thickness. A critical intensity of 5 μW/μm 2 has been observed on a microcavity of finesse 250, with a nonlinear medium of only 18 GaAs quantum wells of 10 nm thickness. Further improvements of the Bragg mirror quality resulted in a finesse of 700 and a power-lifetime product of 15 fJ/μm 2. Microresonator pixellation allows to obtain 2-dimensional arrays. A thermally-induced alloy-mixing technique is described, which produced a 110 meV carrier confinement energy, together with a refractive index change of -.012, averaged over the 2.6 μm nonlinear medium thickness. The resulting electrical and optical confinement is shown to improve the nonlinear characteristics, by limiting lateral carrier diffusion and light diffraction.

  14. Examples of Systems of Functions Being Riesz Bases in L_{2}(0,1). Application to a Nonlinear Boundary Value Problem

    CERN Document Server

    Zhidkov, P E

    2001-01-01

    We establish examples of systems of functions being Riesz bases in L_{2}(0,1). We then apply this result to improve a theorem presented in [9] showing that an arbitrary "standard" system of solutions of a nonlinear boundary value problem, normalized to 1 in the same space, is a Riesz basis in this space. The proofs in this work are quite elementary.

  15. Elementary GLOBE: Inquiring About the Earth System Through Elementary Student Investigations

    Science.gov (United States)

    Henderson, S.; Hatheway, B.; Gardiner, L.; Gallagher, S.

    2006-12-01

    Elementary GLOBE was designed to introduce K-4 students to the study of Earth System Science (ESS). Elementary GLOBE forms an instructional unit comprised of five modules that address ESS and interrelated subjects including weather, hydrology, seasons, and soils. Each Elementary GLOBE module contains a science based storybook, classroom learning activities that complement the science content covered in each book, and teacher's notes. The storybooks explore a component of the Earth system and the associated classroom learning activities provide students with a meaningful introduction to technology, a basic understanding of the methods of inquiry, and connection to math and literacy skills. The science content in the books and activities serves as a springboard to GLOBE's scientific protocols. All Elementary GLOBE materials are freely downloadable (www.globe.gov/elementaryglobe) The use of science storybooks with elementary students has proven to be an effective practice in exposing students to science content while providing opportunities for students to improve their reading, writing, and oral communication skills. The Elementary GLOBE storybooks portray kids asking questions about the natural world, doing science investigations, and exploring the world around them. Through the storybook characters, scientific inquiry is modeled for young learners. The associated learning activities provide opportunities for students to practice science inquiry and investigation skills, including observation, recording, measuring, etc. Students also gain exposure and increase their comfort with different tools that scientists use. The learning activities give students experiences with asking questions, conducting scientific investigations, and scientific journaling. Elementary GLOBE fills an important niche in K-4 instruction. The international GLOBE Program brings together students, teachers, and scientists with the basic goals of increasing scientific understanding of the Earth

  16. Nonlinear robust hierarchical control for nonlinear uncertain systems

    Directory of Open Access Journals (Sweden)

    Leonessa Alexander

    1999-01-01

    Full Text Available A nonlinear robust control-system design framework predicated on a hierarchical switching controller architecture parameterized over a set of moving nominal system equilibria is developed. Specifically, using equilibria-dependent Lyapunov functions, a hierarchical nonlinear robust control strategy is developed that robustly stabilizes a given nonlinear system over a prescribed range of system uncertainty by robustly stabilizing a collection of nonlinear controlled uncertain subsystems. The robust switching nonlinear controller architecture is designed based on a generalized (lower semicontinuous Lyapunov function obtained by minimizing a potential function over a given switching set induced by the parameterized nominal system equilibria. The proposed framework robustly stabilizes a compact positively invariant set of a given nonlinear uncertain dynamical system with structured parametric uncertainty. Finally, the efficacy of the proposed approach is demonstrated on a jet engine propulsion control problem with uncertain pressure-flow map data.

  17. Nonlinear scattering in plasmonic nanostructures

    Science.gov (United States)

    Chu, Shi-Wei

    2016-09-01

    Nonlinear phenomena provide novel light manipulation capabilities and innovative applications. Recently, we discovered nonlinear saturation on single-particle scattering of gold nanospheres by continuous-wave laser excitation and innovatively applied to improve microscopic resolution down to λ/8. However, the nonlinearity was limited to the green-orange plasmonic band of gold nanosphere, and the underlying mechanism has not yet been fully understood. In this work, we demonstrated that nonlinear scattering exists for various material/geometry combinations, thus expanding the applicable wavelength range. For near-infrared, gold nanorod is used, while for blue-violet, silver nanospheres are adopted. In terms of mechanism, the nonlinearity may originate from interband/intraband absorption, hot electron, or hot lattice, which are spectrally mixed in the case of gold nanosphere. For gold nanorod and silver nanosphere, nonlinear scattering occurs at plasmonic resonances, which are spectrally far from interband/intraband absorptions, so they are excluded. We found that the nonlinear index is much larger than possible contributions from hot electrons in literature. Therefore, we conclude that hot lattice is the major mechanism. In addition, we propose that similar to z-scan, which is the standard method to characterize nonlinearity of a thin sample, laser scanning microscopy should be adopted as the standard method to characterize nonlinearity from a nanostructure. Our work not only provides the physical mechanism of the nonlinear scattering, but also paves the way toward multi-color superresolution imaging based on non-bleaching plasmonic scattering.

  18. Discrete nonlinear Schrodinger equations with arbitrarily high-order nonlinearities

    DEFF Research Database (Denmark)

    Khare, A.; Rasmussen, Kim Ø; Salerno, M.

    2006-01-01

    A class of discrete nonlinear Schrodinger equations with arbitrarily high-order nonlinearities is introduced. These equations are derived from the same Hamiltonian using different Poisson brackets and include as particular cases the saturable discrete nonlinear Schrodinger equation and the Ablowi......-Ladik equation. As a common property, these equations possess three kinds of exact analytical stationary solutions for which the Peierls-Nabarro barrier is zero. Several properties of these solutions, including stability, discrete breathers, and moving solutions, are investigated....

  19. Dichromatic nonlinear eigenmodes in slab waveguide with chi(2) nonlinearity.

    Science.gov (United States)

    Darmanyan, S A; Nevière, M

    2001-03-01

    The existence of purely nonlinear eigenmodes in a waveguiding structure composed of a slab with quadratic nonlinearity surrounded by (non)linear claddings is reported. Modes having bright and dark solitonlike shapes and consisting of two mutually locked harmonics are identified. Asymmetrical modes are shown to exist in symmetrical environments. Constraints for the existence of the modes are derived in terms of parameters of guiding structure materials.

  20. Nonlinear Schrodinger equation with chaotic, random, and nonperiodic nonlinearity

    CERN Document Server

    Cardoso, W B; Avelar, A T; Bazeia, D; Hussein, M S

    2009-01-01

    In this paper we deal with a nonlinear Schr\\"{o}dinger equation with chaotic, random, and nonperiodic cubic nonlinearity. Our goal is to study the soliton evolution, with the strength of the nonlinearity perturbed in the space and time coordinates and to check its robustness under these conditions. Comparing with a real system, the perturbation can be related to, e.g., impurities in crystalline structures, or coupling to a thermal reservoir which, on the average, enhances the nonlinearity. We also discuss the relevance of such random perturbations to the dynamics of Bose-Einstein Condensates and their collective excitations and transport.

  1. Some current topics on nonlinear conservation laws lectures at the morningside center of mathematics, 1

    CERN Document Server

    Hsiao, Ling

    2000-01-01

    This volume resulted from a year-long program at the Morningside Center of Mathematics at the Academia Sinica in Beijing. It presents an overview of nonlinear conversation laws and introduces developments in this expanding field. Xin's introductory overview of the subject is followed by lecture notes of leading experts who have made fundamental contributions to this field of research. A. Bressan's theory of L^1-well-posedness for entropy weak solutions to systems of nonlinear hyperbolic conversation laws in the class of viscosity solutions is one of the most important results in the past two decades; G. Chen discusses weak convergence methods and various applications to many problems; P. Degond details mathematical modelling of semi-conductor devices; B. Perthame describes the theory of asymptotic equivalence between conservation laws and singular kinetic equations; Z. Xin outlines the recent development of the vanishing viscosity problem and nonlinear stability of elementary wave-a major focus of research in...

  2. Particular solutions to multidimensional PDEs with KdV-type nonlinearity

    Energy Technology Data Exchange (ETDEWEB)

    Zenchuk, A.I., E-mail: zenchuk@itp.ac.ru

    2014-03-01

    We consider a class of particular solutions to the (2+1)-dimensional nonlinear partial differential equation (PDE) u{sub t}+∂{sub x{sub 2}{sup n}}u{sub x{sub 1}}−u{sub x{sub 1}}u=0 (here n is any integer) reducing it to the ordinary differential equation (ODE). In a simplest case, n=1, the ODE is solvable in terms of elementary functions. Next choice, n=2, yields the cnoidal waves for the special case of Zakharov–Kuznetsov equation. The proposed method is based on the deformation of the characteristic of the equation u{sub t}−uu{sub x{sub 1}}=0 and might also be useful in study of the higher-dimensional PDEs with arbitrary linear part and KdV-type nonlinearity (i.e. the nonlinear term is u{sub x{sub 1}}u).

  3. Open Source Energy Simulation for Elementary School

    CERN Document Server

    Lye, Sze Yee

    2012-01-01

    With the interactivity and multiple representation features, computer simulations lend itself to the guided inquiry learning. However, these simulations are usually designed for post-elementary students. Thus, the aim of this study is to investigate how the use of guided inquiry approach with customized energy simulation can improve students' understanding of this topic. In this ongoing research, the case study is adopted. In the first phase of the study, we have modified open source energy simulation based on principles for reducing extraneous processing, existing energy simulation and guided inquiry approach. The modified simulation is sent to teachers for evaluation and the feedback is encouraging. In the next phase of the study, the guided inquiry lesson package involving the energy simulation would be designed and deployed in an elementary classroom. Multiple data sources would be collected to seek a deeper understanding on how this learning package can possibly impact students' understanding of the phys...

  4. Assessing Elementary Lesions in Gout by Ultrasound

    DEFF Research Database (Denmark)

    Terslev, Lene; Gutierrez, Marwin; Christensen, Robin

    2015-01-01

    OBJECTIVE: To test the reliability of the consensus-based ultrasound (US) definitions of elementary gout lesions in patients. METHODS: Eight patients with microscopically proven gout were evaluated by 16 sonographers for signs of double contour (DC), aggregates, erosions, and tophi in the first...... metatarsophalangeal joint and the knee bilaterally. The patients were examined twice using B-mode US to test agreement and inter- and intraobserver reliability of the elementary components. RESULTS: The prevalence of the lesions were DC 52.8%, tophus 61.1%, aggregates 29.8%, and erosions 32.4%. The intraobserver...... reliability was good for all lesions except DC, where it was moderate. The best reliability per lesion was seen for tophus (κ 0.73, 95% CI 0.61-0.85) and lowest for DC (κ 0.53, 95% CI 0.38-0.67). The interobserver reliability was good for tophus and erosions, but fair to moderate for aggregates and DC...

  5. Bubbles, shocks and elementary technical trading strategies

    Science.gov (United States)

    Fry, John

    2014-01-01

    In this paper we provide a unifying framework for a set of seemingly disparate models for bubbles, shocks and elementary technical trading strategies in financial markets. Markets operate by balancing intrinsic levels of risk and return. This seemingly simple observation is commonly over-looked by academics and practitioners alike. Our model shares its origins in statistical physics with others. However, under our approach, changes in market regime can be explicitly shown to represent a phase transition from random to deterministic behaviour in prices. This structure leads to an improved physical and econometric model. We develop models for bubbles, shocks and elementary technical trading strategies. The list of empirical applications is both interesting and topical and includes real-estate bubbles and the on-going Eurozone crisis. We close by comparing the results of our model with purely qualitative findings from the finance literature.

  6. On the Origin of Elementary Particle Masses

    CERN Document Server

    Hansson, Johan

    2012-01-01

    The oldest enigma in fundamental particle physics is: Where do the observed masses of elementary particles come from? Inspired by observation of the empirical particle mass spectrum we propose that the masses of elementary particles arise solely due to the self-interaction of the fields associated with a particle. We thus assume that the mass is proportional to the strength of the interaction of the field with itself. A simple application of this idea to the fermions is seen to yield a mass for the neutrino in line with constraints from direct experimental upper limits and correct order of magnitude predictions of mass separations between neutrinos, charged leptons and quarks. The neutrino interacts only through the weak force, hence becomes light. The electron interacts also via electromagnetism and accordingly becomes heavier. The quarks also have strong interactions and become heavy. The photon is the only fundamental particle to remain massless, as it is chargeless. Gluons gain mass comparable to quarks, ...

  7. Effecting change in elementary school science education

    Energy Technology Data Exchange (ETDEWEB)

    Parravano, C.

    1994-12-31

    The mission of the Merck Institute for Science Education is to improve the quality of science education during the formative years of kindergarten through eighth grade. To accomplish this mission, the Institute has three primary goals: Transform the teaching of science to communicate the excitement and relevance of science; Reform the education of teachers to instill in tomorrow`s teachers an understanding and appreciation of science; and Create a consensus on the importance of elementary science education among leaders in education, business, and science. Merck has made a minimum ten year commitment of funding and resources to the Institute. The Institute will work very closely with faculty, administration, and community leaders in target school districts to enhance science education in the elementary grades of their schools. Once the Institute`s goals have been achieved in these initial partner districts, the Institute will replicate its programs in other districts.

  8. Introducing Ergonomics in Two US Elementary Schools

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, C L; Tien, D

    2003-06-25

    The increasing presence of computers and other forms of information and communications technology (ICT) in schools has raised concerns in the United States (US) and elsewhere. Children are using computers more than any other age group in the US. It is not known whether early intensive use of ICT predisposes children to future injury. Ergonomics is not included in state curriculum standards or requirements but can be supported by some of the existing standards. Some who believe that children are better off being educated early about ergonomics are taking action to bring ergonomics into elementary and secondary schools. This paper describes the process used to introduce ergonomics into two elementary schools in two different states by initiators with two different roles.

  9. Nonlinear surface electromagnetic phenomena

    CERN Document Server

    Ponath, H-E

    1991-01-01

    In recent years the physics of electromagnetic surface phenomena has developed rapidly, evolving into technologies for communications and industry, such as fiber and integrated optics. The variety of phenomena based on electromagnetism at surfaces is rich and this book was written with the aim of summarizing the available knowledge in selected areas of the field. The book contains reviews written by solid state and optical physicists on the nonlinear interaction of electromagnetic waves at and with surfaces and films. Both the physical phenomena and some potential applications are

  10. Nonlinear electrodynamics with birefringence

    CERN Document Server

    Kruglov, S I

    2015-01-01

    A new model of nonlinear electrodynamics with three parameters is suggested. The phenomena of vacuum birefringence takes place when there is the external constant magnetic field. We calculate the indices of refraction for two polarizations of electromagnetic waves, parallel and perpendicular to the magnetic induction field. From the Bir\\'{e}fringence Magn\\'{e}tique du Vide (BMV) experiment one of the coefficients, $\\gamma\\approx 10^{-20}$ T$^{-2}$, was estimated. The canonical, symmetrical Belinfante energy-momentum tensors and dilatation current were obtained. The dilatation symmetry and the dual symmetry are broken in the model considered.

  11. Nonlinear diffusion equations

    CERN Document Server

    Wu Zhuo Qun; Li Hui Lai; Zhao Jun Ning

    2001-01-01

    Nonlinear diffusion equations, an important class of parabolic equations, come from a variety of diffusion phenomena which appear widely in nature. They are suggested as mathematical models of physical problems in many fields, such as filtration, phase transition, biochemistry and dynamics of biological groups. In many cases, the equations possess degeneracy or singularity. The appearance of degeneracy or singularity makes the study more involved and challenging. Many new ideas and methods have been developed to overcome the special difficulties caused by the degeneracy and singularity, which

  12. Nonlinear dynamics in psychology

    Directory of Open Access Journals (Sweden)

    Stephen J. Guastello

    2001-01-01

    Full Text Available This article provides a survey of the applications of nonlinear dynamical systems theory to substantive problems encountered in the full scope of psychological science. Applications are organized into three topical areas – cognitive science, social and organizational psychology, and personality and clinical psychology. Both theoretical and empirical studies are considered with an emphasis on works that capture the broadest scope of issues that are of substantive interest to psychological theory. A budding literature on the implications of NDS principles in professional practice is reported also.

  13. Nonlinear Control Systems

    Science.gov (United States)

    2009-11-18

    analytic semigroup T(t) ~ eAl is exponentially stable (Notice that it is also a contraction semigroup ). 3. Be 3(U, Z) and P e £(W, 2) are bounded. 4. Ce...quite often in practice, .4 is self-adjoint. We also note that, since we assume (—A) is sectorial, we work with the semigroup exp(.4f) rather than...Uniform Output Regulation of Nonlinear Sys- tems: A convergent Dynamics Approach, Birkhauser, Boston, 2006. 23 135] A. Pazy, Semigroups of Linear

  14. Nonlinear elliptic systems

    Directory of Open Access Journals (Sweden)

    DJAIRO G. DEFIGUEIREDO

    2000-12-01

    Full Text Available In this paper we treat the question of the existence of solutions of boundary value problems for systems of nonlinear elliptic equations of the form - deltau = f (x, u, v,Ñu,Ñv, - deltav = g(x, u, v, Ñu, Ñv, in omega, We discuss several classes of such systems using both variational and topological methods. The notion of criticality takes into consideration the coupling, which plays important roles in both a priori estimates for the solutions and Palais-Smale conditions for the associated functional in the variational case.

  15. Global Analysis of Nonlinear Dynamics

    CERN Document Server

    Luo, Albert

    2012-01-01

    Global Analysis of Nonlinear Dynamics collects chapters on recent developments in global analysis of non-linear dynamical systems with a particular emphasis on cell mapping methods developed by Professor C.S. Hsu of the University of California, Berkeley. This collection of contributions prepared by a diverse group of internationally recognized researchers is intended to stimulate interests in global analysis of complex and high-dimensional nonlinear dynamical systems, whose global properties are largely unexplored at this time. This book also: Presents recent developments in global analysis of non-linear dynamical systems Provides in-depth considerations and extensions of cell mapping methods Adopts an inclusive style accessible to non-specialists and graduate students Global Analysis of Nonlinear Dynamics is an ideal reference for the community of nonlinear dynamics in different disciplines including engineering, applied mathematics, meteorology, life science, computational science, and medicine.  

  16. Nonlinear evolution of drift instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, W.W.; Krommes, J.A.; Oberman, C.R.; Smith, R.A.

    1984-01-01

    The nonlinear evolution of collisionless drift instabilities in a shear-free magnetic field has been studied by means of gyrokinetic particle simulation as well as numerical integration of model mode-coupling equations. The purpose of the investigation is to identify relevant nonlinear mechanisms responsible for the steady-state drift wave fluctuations. It is found that the saturation of the instability is mainly caused by the nonlinear E x B convection of the resonant electrons and their associated velocity space nonlinearity. The latter also induces energy exchange between the competing modes, which, in turn, gives rise to enhanced diffusion. The nonlinear E x B convection of the ions, which contributes to the nonlinear frequency shift, is also an important ingredient for the saturation.

  17. Pointwise approximation by elementary complete contractions

    CERN Document Server

    Magajna, Bojan

    2009-01-01

    A complete contraction on a C*-algebra A, which preserves all closed two sided ideals J, can be approximated pointwise by elementary complete contractions if and only if the induced map on the tensor product of B with A/J is contractive for every C*-algebra B, ideal J in A and C*-tensor norm on the tensor product. A lifting obstruction for such an approximation is also obtained.

  18. Bringing Science Public Outreach to Elementary Schools

    Science.gov (United States)

    Miller, Lucas; Speck, A.; Tinnin, A.

    2012-01-01

    Many science "museums” already offer fantastic programs for the general public, and even some aimed at elementary school kids. However, these venues are usually located in large cities and are only occasionally used as tools for enriching science education in public schools. Here we present preliminary work to establish exciting educational enrichment environments for public schools that do not easily have access to such facilities. This program is aimed at motivating children's interest in science beyond what they learn in the classroom setting. In this program, we use the experience and experiments/demonstrations developed at a large science museum (in this case, The St. Louis Science Center) and take them into a local elementary school. At the same time, students from the University of Missouri are getting trained on how to present these outreach materials and work with the local elementary schools. Our pilot study has started with implementation of presentations/demonstrations at Benton Elementary School within the Columbia Public School district, Missouri. The school has recently adopted a STEM (Science, Technology, Engineering, and Mathematics) centered learning system throughout all grade levels (K-5), and is therefore receptive to this effort. We have implemented a program in which we have given a series of scientific demonstrations at each grade level's lunch hour. Further enrichment ideas and plans include: addition demonstrations, hands-on experiments, and question and answer sessions. However, the application of these events would be to compliment the curriculum for the appropriate grade level at that time. The focus of this project is to develop public communications which links science museums, college students and local public schools with an emphasis on encouraging college science majors to share their knowledge and to strengthen their ability to work in a public environment.

  19. Current experiments in elementary particle physics. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Galic, H. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Armstrong, F.E. [Lawrence Berkeley Lab., CA (United States); von Przewoski, B. [Indiana Univ. Cyclotron Facility, Bloomington, IN (United States)] [and others

    1994-08-01

    This report contains summaries of 568 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1988 are excluded. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, INS (Tokyo), ITEP (Moscow), IUCF (Bloomington), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

  20. THE RELATIONSHIPS OF THREE ELEMENTARY CELLULAR AUTOMATA

    Institute of Scientific and Technical Information of China (English)

    Zhisong JIANG

    2006-01-01

    Limit language complexity of cellular automata which is first posed by S. Wolfram has become a new branch of cellular automata. In this paper, we obtain two interesting relationships between elementary cellular automata of rules 126, 146(182) and 18, and prove that if the limit language of rule 18 is not regular, nor are the limit languages of rules 126 and 146(182).

  1. Introducing Types into Elementary Formal Systems

    OpenAIRE

    Kiwata, Kazuhiro; Arikawa, Setsuo

    1994-01-01

    The elementary formal systems (EFS's for short) work as a theoretical basis in the various fields of computer science such as formal language theory, programming semantics, machine learning and so on. In this paper, we first define proof figures which illustrate proofs of EFS and show standard proof figures for ground atoms which are distinctive in the usage of inference rules. Then we formalize typed EFS, which is a natural extension of EFS obtained by replacing variables by typed variables ...

  2. On an elementary definition of visual saliency

    DEFF Research Database (Denmark)

    Loog, Marco

    2008-01-01

    on probabilistic and information or decision theoretic considerations have been proposed. These provide experimentally successful, appealing, low-level, operational, and elementary definitions of visual saliency (see eg, Bruce, 2005 Neurocomputing 65 125 - 133). Here, I demonstrate that, in fact, all......, surprisingly, without the need to refer back to previously observed data. Furthermore, it follows that it is actually not the statistics of the visual scene that would determine what is salient but the low-level features that probe the scene....

  3. Entropy, subentropy and the elementary symmetric functions

    OpenAIRE

    Jozsa, Richard; Mitchison, Graeme

    2013-01-01

    We use complex contour integral techniques to study the entropy H and subentropy Q as functions of the elementary symmetric polynomials, revealing a series of striking properties. In particular for these variables, derivatives of -Q are equal to derivatives of H of one higher order and the first derivatives of H and Q are seen to be completely monotone functions. It then follows that exp (-H) and exp(-Q) are Laplace transforms of infinitely divisible probability distributions.

  4. Current experiments in elementary particle physics, 1989

    CERN Document Server

    Lawrence Berkeley Nat. Laboratory. Berkeley; Armstrong, F E; Trippe, T G; Yost, G P; Oyanagi, Y; Dodder, D C; Ryabov, Yu G; Slabospitsky, S R; Frosch, R; Olin, A; Lehar, F; Klumov, I A; Ivanov, I I

    1989-01-01

    Contains more than 1,800 experiments in elementary particle physics from the Experience database. Search and browse by author; title; experiment number or prefix; institution; date approved, started or completed; accelerator or detector; polarization, reaction, final state or particle; or by papers produced. Maintained at SLAC for the Particle Data Group. Supplies the information for Current Experiments in Particle Physics (LBL-91). Print version updated every second year.

  5. Z-scan theory for nonlocal nonlinear media with simultaneous nonlinear refraction and nonlinear absorption.

    Science.gov (United States)

    Rashidian Vaziri, Mohammad Reza

    2013-07-10

    In this paper, the Z-scan theory for nonlocal nonlinear media has been further developed when nonlinear absorption and nonlinear refraction appear simultaneously. To this end, the nonlinear photoinduced phase shift between the impinging and outgoing Gaussian beams from a nonlocal nonlinear sample has been generalized. It is shown that this kind of phase shift will reduce correctly to its known counterpart for the case of pure refractive nonlinearity. Using this generalized form of phase shift, the basic formulas for closed- and open-aperture beam transmittances in the far field have been provided, and a simple procedure for interpreting the Z-scan results has been proposed. In this procedure, by separately performing open- and closed-aperture Z-scan experiments and using the represented relations for the far-field transmittances, one can measure the nonlinear absorption coefficient and nonlinear index of refraction as well as the order of nonlocality. Theoretically, it is shown that when the absorptive nonlinearity is present in addition to the refractive nonlinearity, the sample nonlocal response can noticeably suppress the peak and enhance the valley of the Z-scan closed-aperture transmittance curves, which is due to the nonlocal action's ability to change the beam transverse dimensions.

  6. Topics on nonlinear generalized functions

    CERN Document Server

    Colombeau, J F

    2011-01-01

    The aim of this paper is to give the text of a recent introduction to nonlinear generalized functions exposed in my talk in the congress gf2011, which was asked by several participants. Three representative topics were presented: two recalls "Nonlinear generalized functions and their connections with distribution theory", "Examples of applications", and a recent development: "Locally convex topologies and compactness: a functional analysis of nonlinear generalized functions".

  7. Nonlinear Ultrasonic Phased Array Imaging

    Science.gov (United States)

    Potter, J. N.; Croxford, A. J.; Wilcox, P. D.

    2014-10-01

    This Letter reports a technique for the imaging of acoustic nonlinearity. By contrasting the energy of the diffuse field produced through the focusing of an ultrasonic array by delayed parallel element transmission with that produced by postprocessing of sequential transmission data, acoustic nonlinearity local to the focal point is measured. Spatially isolated wave distortion is inferred without requiring interrogation of the wave at the inspection point, thereby allowing nonlinear imaging through depth.

  8. Nonlinear ultrasonic phased array imaging

    OpenAIRE

    Potter, J N; Croxford, A.J.; Wilcox, P. D.

    2014-01-01

    This Letter reports a technique for the imaging of acoustic nonlinearity. By contrasting the energy of the diffuse field produced through the focusing of an ultrasonic array by delayed parallel element transmission with that produced by postprocessing of sequential transmission data, acoustic nonlinearity local to the focal point is measured. Spatially isolated wave distortion is inferred without requiring interrogation of the wave at the inspection point, thereby allowing nonlinear imaging t...

  9. Research on Nonlinear Dynamical Systems.

    Science.gov (United States)

    1983-01-10

    investigated fundamental aspects of functional differential equations, including qualitative questions (stability, nonlinear oscillations ), in 142,45,47,52...Bifurcation in the Duffing equation with several parameters, II. Proc. of the Royal Society of Edinburgh, Series A, 79A (1977), pp.317-326. 1I.J (with ;Ibtoas...Lecture Notes in Mathematics, Vol. 730 (1979). [54] Nonlinear oscillations in equations with delays. Proc. at A.M.S. 10th Summer Seminar on Nonlinear

  10. Nonlinear ultrasonic phased array imaging.

    Science.gov (United States)

    Potter, J N; Croxford, A J; Wilcox, P D

    2014-10-03

    This Letter reports a technique for the imaging of acoustic nonlinearity. By contrasting the energy of the diffuse field produced through the focusing of an ultrasonic array by delayed parallel element transmission with that produced by postprocessing of sequential transmission data, acoustic nonlinearity local to the focal point is measured. Spatially isolated wave distortion is inferred without requiring interrogation of the wave at the inspection point, thereby allowing nonlinear imaging through depth.

  11. Remote Atmospheric Nonlinear Optical Magnetometry

    Science.gov (United States)

    2014-04-28

    Boyd , Nonlinear Optics (Elsevier, Burlington, MA, 2008). [13] M. Scully and S. Zubairy, Quantum Optics (Cambridge U. Press, Cambridge, UK, 1997...Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/6703--14-9548 Remote Atmospheric Nonlinear Optical Magnetometry PhilliP SPrangle...b. ABSTRACT c. THIS PAGE 18. NUMBER OF PAGES 17. LIMITATION OF ABSTRACT Remote Atmospheric Nonlinear Optical Magnetometry Phillip Sprangle, Luke

  12. Applications of nonlinear fiber optics

    CERN Document Server

    Agrawal, Govind

    2008-01-01

    * The only book describing applications of nonlinear fiber optics * Two new chapters on the latest developments: highly nonlinear fibers and quantum applications* Coverage of biomedical applications* Problems provided at the end of each chapterThe development of new highly nonlinear fibers - referred to as microstructured fibers, holey fibers and photonic crystal fibers - is the next generation technology for all-optical signal processing and biomedical applications. This new edition has been thoroughly updated to incorporate these key technology developments.The bo

  13. Linearization of conservative nonlinear oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Belendez, A; Alvarez, M L [Departamento de Fisica, IngenierIa de Sistemas y TeorIa de la Senal, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain); Fernandez, E; Pascual, I [Departamento de Optica, FarmacologIa y AnatomIa, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain)], E-mail: a.belendez@ua.es

    2009-03-11

    A linearization method of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force which allows us to obtain a frequency-amplitude relation which is valid not only for small but also for large amplitudes and, sometimes, for the complete range of oscillation amplitudes. Some conservative nonlinear oscillators are analysed to illustrate the usefulness and effectiveness of the technique.

  14. Problems in nonlinear resistive MHD

    Energy Technology Data Exchange (ETDEWEB)

    Turnbull, A.D.; Strait, E.J.; La Haye, R.J.; Chu, M.S.; Miller, R.L. [General Atomics, San Diego, CA (United States)

    1998-12-31

    Two experimentally relevant problems can relatively easily be tackled by nonlinear MHD codes. Both problems require plasma rotation in addition to the nonlinear mode coupling and full geometry already incorporated into the codes, but no additional physics seems to be crucial. These problems discussed here are: (1) nonlinear coupling and interaction of multiple MHD modes near the B limit and (2) nonlinear coupling of the m/n = 1/1 sawtooth mode with higher n gongs and development of seed islands outside q = 1.

  15. Asymptotics for dissipative nonlinear equations

    CERN Document Server

    Hayashi, Nakao; Kaikina, Elena I; Shishmarev, Ilya A

    2006-01-01

    Many of problems of the natural sciences lead to nonlinear partial differential equations. However, only a few of them have succeeded in being solved explicitly. Therefore different methods of qualitative analysis such as the asymptotic methods play a very important role. This is the first book in the world literature giving a systematic development of a general asymptotic theory for nonlinear partial differential equations with dissipation. Many typical well-known equations are considered as examples, such as: nonlinear heat equation, KdVB equation, nonlinear damped wave equation, Landau-Ginzburg equation, Sobolev type equations, systems of equations of Boussinesq, Navier-Stokes and others.

  16. Focus issue introduction: nonlinear optics.

    Science.gov (United States)

    Boulanger, Benoît; Cundiff, Steven T; Gauthier, Daniel J; Karlsson, Magnus; Lu, Yan-Qing; Norwood, Robert A; Skryabin, Dmitry; Taira, Takunori

    2011-11-07

    It is now fifty years since the original observation of second harmonic generation ushered in the field of nonlinear optics, close on the heels of the invention of the laser. This feature issue celebrates this anniversary with papers that span the range from new nonlinear optical materials, through the increasingly novel methods that have been developed for phase matching, to emerging areas such as nonlinear metamaterials and plasmonic enhancement of optical properties. It is clear that the next fifty years of nonlinear optics will witness a proliferation of new applications with increasing technological impact.

  17. Nonlocal homogenization for nonlinear metamaterials

    CERN Document Server

    Gorlach, Maxim A; Lapine, Mikhail; Kivshar, Yuri S; Belov, Pavel A

    2016-01-01

    We present a consistent theoretical approach for calculating effective nonlinear susceptibilities of metamaterials taking into account both frequency and spatial dispersion. Employing the discrete dipole model, we demonstrate that effects of spatial dispersion become especially pronounced in the vicinity of effective permittivity resonance where nonlinear susceptibilities reach their maxima. In that case spatial dispersion may enable simultaneous generation of two harmonic signals with the same frequency and polarization but different wave vectors. We also prove that the derived expressions for nonlinear susceptibilities transform into the known form when spatial dispersion effects are negligible. In addition to revealing new physical phenomena, our results provide useful theoretical tools for analysing resonant nonlinear metamaterials.

  18. Nonlinear Peltier effect in semiconductors

    Science.gov (United States)

    Zebarjadi, Mona; Esfarjani, Keivan; Shakouri, Ali

    2007-09-01

    Nonlinear Peltier coefficient of a doped InGaAs semiconductor is calculated numerically using the Monte Carlo technique. The Peltier coefficient is also obtained analytically for single parabolic band semiconductors assuming a shifted Fermi-Dirac electronic distribution under an applied bias. Analytical results are in agreement with numerical simulations. Key material parameters affecting the nonlinear behavior are doping concentration, effective mass, and electron-phonon coupling. Current density thresholds at which nonlinear behavior is observable are extracted from numerical data. It is shown that the nonlinear Peltier effect can be used to enhance cooling of thin film microrefrigerator devices especially at low temperatures.

  19. Nonlinearities in Behavioral Macroeconomics.

    Science.gov (United States)

    Gomes, Orlando

    2017-07-01

    This article undertakes a journey across the literature on behavioral macroeconomics, with attention concentrated on the nonlinearities that the behavioral approach typically suggests or implies. The emphasis is placed on thinking the macro economy as a living organism, composed of many interacting parts, each one having a will of its own, which is in sharp contrast with the mechanism of the orthodox view (well represented by the neoclassical or new Keynesian dynamic stochastic general equilibrium - DSGE - model). The paper advocates that a thorough understanding of individual behavior in collective contexts is the only possible avenue to further explore macroeconomic phenomena and the often observed 'anomalies' that the benchmark DSGE macro framework is unable to explain or justify. After a reflection on the role of behavioral traits as a fundamental component of a new way of thinking the economy, the article proceeds with a debate on some of the most relevant frameworks in the literature that somehow link macro behavior and nonlinearities; covered subjects include macro models with disequilibrium rules, agent-based models that highlight interaction and complexity, evolutionary switching frameworks, and inattention based decision problems. These subjects have, as a fundamental point in common, the use of behavioral elements to transform existing interpretations of the economic reality, making it more evident how irregular fluctuations emerge and unfold on the aggregate.

  20. Improved nonlinear prediction method

    Science.gov (United States)

    Adenan, Nur Hamiza; Md Noorani, Mohd Salmi

    2014-06-01

    The analysis and prediction of time series data have been addressed by researchers. Many techniques have been developed to be applied in various areas, such as weather forecasting, financial markets and hydrological phenomena involving data that are contaminated by noise. Therefore, various techniques to improve the method have been introduced to analyze and predict time series data. In respect of the importance of analysis and the accuracy of the prediction result, a study was undertaken to test the effectiveness of the improved nonlinear prediction method for data that contain noise. The improved nonlinear prediction method involves the formation of composite serial data based on the successive differences of the time series. Then, the phase space reconstruction was performed on the composite data (one-dimensional) to reconstruct a number of space dimensions. Finally the local linear approximation method was employed to make a prediction based on the phase space. This improved method was tested with data series Logistics that contain 0%, 5%, 10%, 20% and 30% of noise. The results show that by using the improved method, the predictions were found to be in close agreement with the observed ones. The correlation coefficient was close to one when the improved method was applied on data with up to 10% noise. Thus, an improvement to analyze data with noise without involving any noise reduction method was introduced to predict the time series data.

  1. Nonlinear Response of Strong Nonlinear System Arisen in Polymer Cushion

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2013-01-01

    Full Text Available A dynamic model is proposed for a polymer foam-based nonlinear cushioning system. An accurate analytical solution for the nonlinear free vibration of the system is derived by applying He's variational iteration method, and conditions for resonance are obtained, which should be avoided in the cushioning design.

  2. Preservice elementary teachers learning of astronomy

    Science.gov (United States)

    Fidler, Chuck Gary

    The dissertation presents a new approach for the study of preservice elementary teacher astronomy education. The approach suggests that learning astronomical concepts are facilitated by greater sophistication in scale perception and spatial-aptitude. This dissertation is underscored by the national call for elementary science education reform efforts and suggests certain strategies shown more effective for the development of accurate astronomical comprehension. The present research study describes how preservice elementary teachers conceptualize and communicate ideas about Space. Instead of assuming a universal mental conception of cosmic orientations and relationships, the dissertation claims that the perception of Space related dimensions vary among preservice elementary teachers. Furthermore, the dissertation suggests individual perceptions of the scale sizes and orientations of celestial systems have direct influences on mental models used to organize and communicate astronomical information. The development of inaccurate mental models of the scaled dimensions of Space may perpetuate the teacher-student cycle of misconception and naive-theory generation among children in elementary education settings. The ability to conceptualize the vast cosmos is facilitated by the minds ability to think about vast scales and orientations of celestial objects. The Earth-based perspective of astronomy education compels the learner to think about astronomical principles within imaginary frames of reference and across unfamiliar scaled dimensions. Therefore, mental astronomical model building is underscored by the perception of scale and cosmic spatiality. This study suggests these cognitive skill sets are interconnected and facilitate the learning of accurate astronomy principles; as well as play an important role when designing an astronomy education program for preservice elementary teachers. This research study is comprised of three separate standalone articles designed and

  3. Interaction of elementary waves for equations of potential flow

    Institute of Scientific and Technical Information of China (English)

    陈恕行; 王辉

    1997-01-01

    Interaction of elementary waves for equations of unsteady potential flow in gas dynamics is considered . Under the assumptions on weakness of strength of the elementary waves the structure of solutions has been given in various cases of interaction of simple wave with shock, or interaction between simple waves or shocks. Hence the complete results on interaction of weak elementary waves for second-order equation of potential flow are obtained.

  4. Obesity status trajectory groups among elementary school children

    OpenAIRE

    Chen, Tzu-An; Baranowski, Tom; Jennette P. Moreno; O’Connor, Teresia M; Hughes, Sheryl O; Baranowski, Janice; Woehler, Deborah; Kimbro, Rachel T.; Johnston, Craig A.

    2016-01-01

    Background Little is known about patterns in the transition from healthy weight to overweight or obesity during the elementary school years. This study examined whether there were distinct body mass index (BMI) trajectory groups among elementary school children, and predictors of trajectory group membership. Methods This is a secondary analysis of 1651 elementary school children with complete biannual longitudinal data from kindergarten to the beginning of 5th grade. Heights and weights were ...

  5. Preservice Elementary Teachers' Reflection on Narrative Images of Inquiry

    Science.gov (United States)

    Dietz, Christine M.; Davis, Elizabeth A.

    2009-06-01

    Preservice elementary teachers face challenges in learning to teach science. Educative curriculum materials, designed to promote teacher learning, can provide support for overcoming these challenges. The educative curriculum materials used in this study provide narrative vignettes describing a teacher’s decision making with regard to lesson plans. As part of an elementary science methods course, 40 preservice teachers were asked to reflect on and respond to the narratives. Results suggest that descriptions of teaching situated in lesson plans can promote productive reflection for preservice teachers. This study informs the design of educative curriculum materials and elementary science teacher education experiences and helps improve the pedagogical content knowledge of elementary science teacher educators.

  6. Expansion Nets and Expansion Processes of Elementary Net Systems

    Institute of Scientific and Technical Information of China (English)

    曹存根

    1995-01-01

    Occurrence nets are insufficient to precisely describe executions of elementary net systems with contacts.Traditionally,S-complementation is used for removal of contacts from the systems.Although the main behavior and properties of the original elementary net systems are preserved during S-complementation,their topologies may be changed greatly.This paper introduces a new kind of nets-expansion nets-for representing behavior of elementary net systems.As shown in the paper,expansion nets are natural as well as sufficient for describing the precise behavior of elementary net systems with or without contactks.

  7. Nonlinear Evolution of Ferroelectric Domains

    Institute of Scientific and Technical Information of China (English)

    WeiLU; Dai-NingFANG; 等

    1997-01-01

    The nonlinear evolution of ferroelectric domains is investigated in the paper and amodel is proposed which can be applied to numerical computation.Numerical results show that the model can accurately predict some nonlinear behavior and consist with those experimental results.

  8. Nonlinear Electrodynamics and black holes

    CERN Document Server

    Breton, N; Breton, Nora; Garcia-Salcedo, Ricardo

    2007-01-01

    It is addressed the issue of black holes with nonlinear electromagnetic field, focussing mainly in the Born-Infeld case. The main features of these systems are described, for instance, geodesics, energy conditions, thermodynamics and isolated horizon aspects. Also are revised some black hole solutions of alternative nonlinear electrodynamics and its inconveniences.

  9. Space curves, anholonomy and nonlinearity

    Indian Academy of Sciences (India)

    Radha Balakrishnan

    2005-04-01

    Using classical differential geometry, we discuss the phenomenon of anholonomy that gets associated with a static and a moving curve. We obtain the expressions for the respective geometric phases in the two cases and interpret them. We show that there is a close connection between anholonomy and nonlinearity in a wide class of nonlinear systems.

  10. Balancing for unstable nonlinear systems

    NARCIS (Netherlands)

    Scherpen, J.M.A.

    1993-01-01

    A previously obtained method of balancing for stable nonlinear systems is extended to unstable nonlinear systems. The similarity invariants obtained by the concept of LQG balancing for an unstable linear system can also be obtained by considering a past and future energy function of the system. By c

  11. Nonlinear diffusion and superconducting hysteresis

    Energy Technology Data Exchange (ETDEWEB)

    Mayergoyz, I.D. [Univ. of Maryland, College Park, MD (United States)

    1996-12-31

    Nonlinear diffusion of electromagnetic fields in superconductors with ideal and gradual resistive transitions is studied. Analytical results obtained for linear and nonlinear polarizations of electromagnetic fields are reported. These results lead to various extensions of the critical state model for superconducting hysteresis.

  12. Nonlinear energy harvesting

    Energy Technology Data Exchange (ETDEWEB)

    Lallart, Mickael; Guyomar, Daniel, E-mail: mickael.lallart@insa-lyon.fr [LGEF, INSA-Lyon, Universite de Lyon, 8 rue de la Physique, F-69621 (France)

    2011-10-29

    The proliferation of wearable and left-behind devices has raised the issue of powering such systems. While primary batteries have been widely used in order to address this issue, recent trends have focused on energy harvesting products that feature high reliability and low maintenance issues. Among all the ambient sources available for energy harvesting, vibrations and heat have been of significant interest among the research community for small-scale devices. However, the conversion abilities of materials are still limited when dealing with systems featuring small dimensions. The purpose of this paper is to presents an up-to-date view of nonlinear approaches for increasing the efficiency of electromechanical and electrocaloric conversion mechanisms. From the modeling of the operation principles of the different architectures, a comparative analysis will be exposed, emphasizing the advantages and drawbacks of the presented concepts, in terms of maximal output power (under constant vibration magnitude or taking into account the damping effect), load independence, and implementation easiness.

  13. Nonlinear organic plasmonics

    CERN Document Server

    Fainberg, B D

    2015-01-01

    Purely organic materials with negative and near-zero dielectric permittivity can be easily fabricated. Here we develop a theory of nonlinear non-steady-state organic plasmonics with strong laser pulses. The bistability response of the electron-vibrational model of organic materials in the condensed phase has been demonstrated. Non-steady-state organic plasmonics enable us to obtain near-zero dielectric permittivity during a short time. We have proposed to use non-steady-state organic plasmonics for the enhancement of intersite dipolar energy-transfer interaction in the quantum dot wire that influences on electron transport through nanojunctions. Such interactions can compensate Coulomb repulsions for particular conditions. We propose the exciton control of Coulomb blocking in the quantum dot wire based on the non-steady-state near-zero dielectric permittivity of the organic host medium.

  14. Nonlinear Water Waves

    CERN Document Server

    2016-01-01

    This volume brings together four lecture courses on modern aspects of water waves. The intention, through the lectures, is to present quite a range of mathematical ideas, primarily to show what is possible and what, currently, is of particular interest. Water waves of large amplitude can only be fully understood in terms of nonlinear effects, linear theory being not adequate for their description. Taking advantage of insights from physical observation, experimental evidence and numerical simulations, classical and modern mathematical approaches can be used to gain insight into their dynamics. The book presents several avenues and offers a wide range of material of current interest. Due to the interdisciplinary nature of the subject, the book should be of interest to mathematicians (pure and applied), physicists and engineers. The lectures provide a useful source for those who want to begin to investigate how mathematics can be used to improve our understanding of water wave phenomena. In addition, some of the...

  15. Nonlinear estimation and classification

    CERN Document Server

    Hansen, Mark; Holmes, Christopher; Mallick, Bani; Yu, Bin

    2003-01-01

    Researchers in many disciplines face the formidable task of analyzing massive amounts of high-dimensional and highly-structured data This is due in part to recent advances in data collection and computing technologies As a result, fundamental statistical research is being undertaken in a variety of different fields Driven by the complexity of these new problems, and fueled by the explosion of available computer power, highly adaptive, non-linear procedures are now essential components of modern "data analysis," a term that we liberally interpret to include speech and pattern recognition, classification, data compression and signal processing The development of new, flexible methods combines advances from many sources, including approximation theory, numerical analysis, machine learning, signal processing and statistics The proposed workshop intends to bring together eminent experts from these fields in order to exchange ideas and forge directions for the future

  16. Nonlinear transmission sputtering

    Science.gov (United States)

    Bitensky, I. S.; Sigmund, P.

    1996-05-01

    General expressions have been derived for the nonlinear yield of transmission sputtering for an incident polyatomic ion under the assumption that the molecule breaks up on entering the target and that sputter yields are enhanced due to proximity of atomic trajectories. Special attention is given to the case of negligible Coulomb explosion where projectile atoms penetrate independently. For weakly overlapping trajectories, the yield enhancement factor of a polyatomic molecule can be expressed by that of a diatom, amended with a correction for triple correlations if necessary. This expression is in good agreement with recent experimental findings on phenylalanine targets. Pertinent results on multiple scattering of atomic ions are reviewed and applied to independently-moving fragment atoms. The merits of measurements at variable layer thickness in addition to variable projectile energy are mentioned.

  17. Perspectives on Nonlinear Filtering

    KAUST Repository

    Law, Kody

    2015-01-07

    The solution to the problem of nonlinear filtering may be given either as an estimate of the signal (and ideally some measure of concentration), or as a full posterior distribution. Similarly, one may evaluate the fidelity of the filter either by its ability to track the signal or its proximity to the posterior filtering distribution. Hence, the field enjoys a lively symbiosis between probability and control theory, and there are plenty of applications which benefit from algorithmic advances, from signal processing, to econometrics, to large-scale ocean, atmosphere, and climate modeling. This talk will survey some recent theoretical results involving accurate signal tracking with noise-free (degenerate) dynamics in high-dimensions (infinite, in principle, but say d between 103 and 108 , depending on the size of your application and your computer), and high-fidelity approximations of the filtering distribution in low dimensions (say d between 1 and several 10s).

  18. Nonlinear rotordynamics analysis

    Science.gov (United States)

    Day, W. B.; Zalik, R. A.

    1986-01-01

    Three analytic consequences of the nonlinear Jeffcott equations are examined. The primary application of these analyses is directed toward understanding the excessive vibrations recorded in the Liquid Oxygen (LOX) pump of the Space Shuttle Main Engine (SSME) during hot firing ground testing. The first task is to provide bounds on the coefficients of the equations which delimit the two cases of numerical solution as a circle or an annulus. The second task examines the mathematical generalization to multiple forcing functions, which includes the special problems of mass imbalance, side force, rubbing, and combination of these forces. Finally, stability and boundedness of the steady-state solutions is discussed and related to the corresponding linear problem.

  19. Nonlinearities in vegetation functioning

    Science.gov (United States)

    Ceballos-Núñez, Verónika; Müller, Markus; Metzler, Holger; Sierra, Carlos

    2016-04-01

    Given the current drastic changes in climate and atmospheric CO2 concentrations, and the role of vegetation in the global carbon cycle, there is increasing attention to the carbon allocation component in biosphere terrestrial models. Improving the representation of C allocation in models could be the key to having better predictions of the fate of C once it enters the vegetation and is partitioned to C pools of different residence times. C allocation has often been modeled using systems of ordinary differential equations, and it has been hypothesized that most models can be generalized with a specific form of a linear dynamical system. However, several studies have highlighted discrepancies between empirical observations and model predictions, attributing these differences to problems with model structure. Although efforts have been made to compare different models, the outcome of these qualitative assessments has been a conceptual categorization of them. In this contribution, we introduce a new effort to identify the main properties of groups of models by studying their mathematical structure. For this purpose, we performed a literature research of the relevant models of carbon allocation in vegetation and developed a database with their representation in symbolic mathematics. We used the Python package SymPy for symbolic mathematics as a common language and manipulated the models to calculate their Jacobian matrix at fixed points and their eigenvalues, among other mathematical analyses. Our preliminary results show a tendency of inverse proportionality between model complexity and size of time/space scale; complex interactions between the variables controlling carbon allocation in vegetation tend to operate at shorter time/space scales, and vice-versa. Most importantly, we found that although the linear structure is common, other structures with non-linearities have been also proposed. We, therefore, propose a new General Model that can accommodate these

  20. Nonlinear field space cosmology

    Science.gov (United States)

    Mielczarek, Jakub; Trześniewski, Tomasz

    2017-08-01

    We consider the FRW cosmological model in which the matter content of the Universe (playing the role of an inflaton or quintessence) is given by a novel generalization of the massive scalar field. The latter is a scalar version of the recently introduced nonlinear field space theory, where the physical phase space of a given field is assumed to be compactified at large energies. For our analysis, we choose the simple case of a field with the spherical phase space and endow it with the generalized Hamiltonian analogous to the XXZ Heisenberg model, normally describing a system of spins in condensed matter physics. Subsequently, we study both the homogenous cosmological sector and linear perturbations of such a test field. In the homogenous sector, we find that nonlinearity of the field phase space is becoming relevant for large volumes of the Universe and can lead to a recollapse, and possibly also at very high energies, leading to the phase of a bounce. Quantization of the field is performed in the limit where the nontrivial nature of its phase space can be neglected, while there is a nonvanishing contribution from the Lorentz symmetry breaking term of the Hamiltonian. As a result, in the leading order of the XXZ anisotropy parameter, we find that the inflationary spectral index remains unmodified with respect to the standard case but the total amplitude of perturbations is subject to a correction. The Bunch-Davies vacuum state also becomes appropriately corrected. The proposed new approach is bringing cosmology and condensed matter physics closer together, which may turn out to be beneficial for both disciplines.

  1. NONLINEAR STABILITY FOR EADY'S MODEL

    Institute of Scientific and Technical Information of China (English)

    LIU Yong-ming; QIU Ling-cun

    2005-01-01

    Poincaré type integral inequality plays an important role in the study of nonlinear stability ( in the sense of Arnold's second theorem) for three-dimensional quasigeostophic flow. The nonlinear stability of Eady's model is one of the most important cases in the application of the method. But the best nonlinear stability criterion obtained so far and the linear stability criterion are not coincident. The two criteria coincide only when the period of the channel is infinite.additional conservation law of momentum and by rigorous estimate of integral inequality. So the new nonlinear stability criterion was obtained, which shows that for Eady 's model in the periodic channel, the linear stable implies the nonlinear stable.

  2. Nonlinear Waves in Complex Systems

    DEFF Research Database (Denmark)

    2007-01-01

    The study of nonlinear waves has exploded due to the combination of analysis and computations, since the discovery of the famous recurrence phenomenon on a chain of nonlinearly coupled oscillators by Fermi-Pasta-Ulam fifty years ago. More than the discovery of new integrable equations, it is the ......The study of nonlinear waves has exploded due to the combination of analysis and computations, since the discovery of the famous recurrence phenomenon on a chain of nonlinearly coupled oscillators by Fermi-Pasta-Ulam fifty years ago. More than the discovery of new integrable equations......, it is the universality and robustness of the main models with respect to perturbations that developped the field. This is true for both continuous and discrete equations. In this volume we keep this broad view and draw new perspectives for nonlinear waves in complex systems. In particular we address energy flow...

  3. Terahertz Nonlinearity in Graphene Plasmons

    CERN Document Server

    Jadidi, Mohammad M; Winnerl, Stephan; Sushkov, Andrei B; Drew, H Dennis; Murphy, Thomas E; Mittendorff, Martin

    2015-01-01

    Sub-wavelength graphene structures support localized plasmonic resonances in the terahertz and mid-infrared spectral regimes. The strong field confinement at the resonant frequency is predicted to significantly enhance the light-graphene interaction, which could enable nonlinear optics at low intensity in atomically thin, sub-wavelength devices. To date, the nonlinear response of graphene plasmons and their energy loss dynamics have not been experimentally studied. We measure and theoretically model the terahertz nonlinear response and energy relaxation dynamics of plasmons in graphene nanoribbons. We employ a THz pump-THz probe technique at the plasmon frequency and observe a strong saturation of plasmon absorption followed by a 10 ps relaxation time. The observed nonlinearity is enhanced by two orders of magnitude compared to unpatterned graphene with no plasmon resonance. We further present a thermal model for the nonlinear plasmonic absorption that supports the experimental results.

  4. Fast Numerical Nonlinear Fourier Transforms

    CERN Document Server

    Wahls, Sander

    2014-01-01

    The nonlinear Fourier transform, which is also known as the forward scattering transform, decomposes a periodic signal into nonlinearly interacting waves. In contrast to the common Fourier transform, these waves no longer have to be sinusoidal. Physically relevant waveforms are often available for the analysis instead. The details of the transform depend on the waveforms underlying the analysis, which in turn are specified through the implicit assumption that the signal is governed by a certain evolution equation. For example, water waves generated by the Korteweg-de Vries equation can be expressed in terms of cnoidal waves. Light waves in optical fiber governed by the nonlinear Schr\\"dinger equation (NSE) are another example. Nonlinear analogs of classic problems such as spectral analysis and filtering arise in many applications, with information transmission in optical fiber, as proposed by Yousefi and Kschischang, being a very recent one. The nonlinear Fourier transform is eminently suited to address them ...

  5. Properties of Nonlinear Dynamo Waves

    Science.gov (United States)

    Tobias, S. M.

    1997-01-01

    Dynamo theory offers the most promising explanation of the generation of the sun's magnetic cycle. Mean field electrodynamics has provided the platform for linear and nonlinear models of solar dynamos. However, the nonlinearities included are (necessarily) arbitrarily imposed in these models. This paper conducts a systematic survey of the role of nonlinearities in the dynamo process, by considering the behaviour of dynamo waves in the nonlinear regime. It is demonstrated that only by considering realistic nonlinearities that are non-local in space and time can modulation of the basic dynamo wave he achieved. Moreover, this modulation is greatest when there is a large separation of timescales provided by including a low magnetic Prandtl number in the equation for the velocity perturbations.

  6. Cubication of conservative nonlinear oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Belendez, Augusto; Alvarez, Mariela L [Departamento de Fisica, Ingenieria de Sistemas y Teoria de la Senal, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain); Fernandez, Elena; Pascual, Inmaculada [Departamento de Optica, FarmacologIa y Anatomia, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain)], E-mail: a.belendez@ua.es

    2009-09-15

    A cubication procedure of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force, and this allows us to approximate the original nonlinear differential equation by a Duffing equation in which the coefficients for the linear and cubic terms depend on the initial amplitude, A, while in a Taylor expansion of the restoring force these coefficients are independent of A. The replacement of the original nonlinear equation by an approximate Duffing equation allows us to obtain an approximate frequency-amplitude relation as a function of the complete elliptic integral of the first kind. Some conservative nonlinear oscillators are analysed to illustrate the usefulness and effectiveness of this scheme.

  7. Nonlinear Oscillators in Space Physics

    Science.gov (United States)

    Lester,Daniel; Thronson, Harley

    2011-01-01

    We discuss dynamical systems that produce an oscillation without an external time dependent source. Numerical results are presented for nonlinear oscillators in the Em1h's atmosphere, foremost the quasi-biennial oscillation (QBOl. These fluid dynamical oscillators, like the solar dynamo, have in common that one of the variables in a governing equation is strongly nonlinear and that the nonlinearity, to first order, has particular form. of 3rd or odd power. It is shown that this form of nonlinearity can produce the fundamental li'equency of the internal oscillation. which has a period that is favored by the dynamical condition of the fluid. The fundamental frequency maintains the oscillation, with no energy input to the system at that particular frequency. Nonlinearities of 2nd or even power could not maintain the oscillation.

  8. Asymptotic expansions in nonlinear rotordynamics

    Science.gov (United States)

    Day, William B.

    1987-01-01

    This paper is an examination of special nonlinearities of the Jeffcott equations in rotordynamics. The immediate application of this analysis is directed toward understanding the excessive vibrations recorded in the LOX pump of the SSME during hot-firing ground testing. Deadband, side force, and rubbing are three possible sources of inducing nonlinearity in the Jeffcott equations. The present analysis initially reduces these problems to the same mathematical description. A special frequency, named the nonlinear natural frequency, is defined and used to develop the solutions of the nonlinear Jeffcott equations as singular asymptotic expansions. This nonlinear natural frequency, which is the ratio of the cross-stiffness and the damping, plays a major role in determining response frequencies.

  9. Nonlinear hyperbolic waves in multidimensions

    CERN Document Server

    Prasad, Phoolan

    2001-01-01

    The propagation of curved, nonlinear wavefronts and shock fronts are very complex phenomena. Since the 1993 publication of his work Propagation of a Curved Shock and Nonlinear Ray Theory, author Phoolan Prasad and his research group have made significant advances in the underlying theory of these phenomena. This volume presents their results and provides a self-contained account and gradual development of mathematical methods for studying successive positions of these fronts.Nonlinear Hyperbolic Waves in Multidimensions includes all introductory material on nonlinear hyperbolic waves and the theory of shock waves. The author derives the ray theory for a nonlinear wavefront, discusses kink phenomena, and develops a new theory for plane and curved shock propagation. He also derives a full set of conservation laws for a front propagating in two space dimensions, and uses these laws to obtain successive positions of a front with kinks. The treatment includes examples of the theory applied to converging wavefronts...

  10. Analysis of Nonlinear Electromagnetic Metamaterials

    CERN Document Server

    Poutrina, Ekaterina; Smith, David R

    2010-01-01

    We analyze the properties of a nonlinear metamaterial formed by integrating nonlinear components or materials into the capacitive regions of metamaterial elements. A straightforward homogenization procedure leads to general expressions for the nonlinear susceptibilities of the composite metamaterial medium. The expressions are convenient, as they enable inhomogeneous system of scattering elements to be described as a continuous medium using the standard notation of nonlinear optics. We illustrate the validity and accuracy of our theoretical framework by performing measurements on a fabricated metamaterial sample composed of an array of split ring resonators (SRRs) with packaged varactors embedded in the capacitive gaps in a manner similar to that of Wang et al. [Opt. Express 16, 16058 (2008)]. Because the SRRs exhibit a predominant magnetic response to electromagnetic fields, the varactor-loaded SRR composite can be described as a magnetic material with nonlinear terms in its effective magnetic susceptibility...

  11. 75 FR 18488 - Office of Elementary and Secondary Education; Overview Information; Enhanced Assessment...

    Science.gov (United States)

    2010-04-12

    ... Office of Elementary and Secondary Education; Overview Information; Enhanced Assessment Instruments..., Enhanced Assessment Grants Program, Office of Elementary and Secondary Education, U.S. Department of... Secretary for Elementary and Secondary Education. BILLING CODE 4000-01-P...

  12. The Nonlinear Analytical Envelope Equation in quadratic nonlinear crystals

    CERN Document Server

    Bache, Morten

    2016-01-01

    We here derive the so-called Nonlinear Analytical Envelope Equation (NAEE) inspired by the work of Conforti et al. [M. Conforti, A. Marini, T. X. Tran, D. Faccio, and F. Biancalana, "Interaction between optical fields and their conjugates in nonlinear media," Opt. Express 21, 31239-31252 (2013)], whose notation we follow. We present a complete model that includes $\\chi^{(2)}$ terms [M. Conforti, F. Baronio, and C. De Angelis, "Nonlinear envelope equation for broadband optical pulses in quadratic media," Phys. Rev. A 81, 053841 (2010)], $\\chi^{(3)}$ terms, and then extend the model to delayed Raman effects in the $\\chi^{(3)}$ term. We therefore get a complete model for ultrafast pulse propagation in quadratic nonlinear crystals similar to the Nonlinear Wave Equation in Frequency domain [H. Guo, X. Zeng, B. Zhou, and M. Bache, "Nonlinear wave equation in frequency domain: accurate modeling of ultrafast interaction in anisotropic nonlinear media," J. Opt. Soc. Am. B 30, 494-504 (2013)], but where the envelope is...

  13. Breatherlike impurity modes in discrete nonlinear lattices

    DEFF Research Database (Denmark)

    Hennig, D.; Rasmussen, Kim; Tsironis, G. P.

    1995-01-01

    We investigate the properties of a disordered generalized discrete nonlinear Schrodinger equation, containing both diagonal and nondiagonal nonlinear terms. The equation models a Linear host lattice doped with nonlinear impurities. We find different types of impurity states that form itinerant...

  14. Younger elementary students waste more school lunch foods than older elementary students

    Science.gov (United States)

    Children may not receive the nutritional benefits from school lunch meals if they do not eat the foods served. This study investigated whether there were differences in school lunch foods consumed and wasted by grade level of elementary school students. In this cross-sectional study, anonymous meal ...

  15. Application of sensitivity analysis in building energy simulations: combining first and second order elementary effects Methods

    CERN Document Server

    Sanchez, David Garcia; Musy, Marjorie; Bourges, Bernard

    2012-01-01

    Sensitivity analysis plays an important role in the understanding of complex models. It helps to identify influence of input parameters in relation to the outputs. It can be also a tool to understand the behavior of the model and then can help in its development stage. This study aims to analyze and illustrate the potential usefulness of combining first and second-order sensitivity analysis, applied to a building energy model (ESP-r). Through the example of a collective building, a sensitivity analysis is performed using the method of elementary effects (also known as Morris method), including an analysis of interactions between the input parameters (second order analysis). Importance of higher-order analysis to better support the results of first order analysis, highlighted especially in such complex model. Several aspects are tackled to implement efficiently the multi-order sensitivity analysis: interval size of the variables, management of non-linearity, usefulness of various outputs.

  16. Higher accurate approximate solutions for the simple pendulum in terms of elementary functions

    Energy Technology Data Exchange (ETDEWEB)

    Belendez, Augusto; Frances, Jorge; Ortuno, Manuel; Gallego, Sergi; Guillermo Bernabeu, Jose, E-mail: a.belendez@ua.e [Departamento de Fisica, IngenierIa de Sistemas y TeorIa de la Senal, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain)

    2010-05-15

    A closed-form approximate expression for the solution of a simple pendulum in terms of elementary functions is obtained. To do this, the exact expression for the maximum tension of the string of the pendulum is first considered and a trial approximate solution depending on some parameters is used, which is substituted in the tension equation. We obtain the parameters for the approximate by means of a term-by-term comparison of the power series expansion for the approximate maximum tension with the corresponding series for the exact one. We believe that this letter may be a suitable and fruitful exercise for teaching and better understanding nonlinear oscillations of a simple pendulum in undergraduate courses on classical mechanics. (letters and comments)

  17. Spatial solitons in nonlinear photonic crystals

    DEFF Research Database (Denmark)

    Corney, Joel Frederick; Bang, Ole

    2000-01-01

    We study solitons in one-dimensional quadratic nonlinear photonic crystals with periodic linear and nonlinear susceptibilities. We show that such crystals support stable bright and dark solitons, even when the effective quadratic nonlinearity is zero.......We study solitons in one-dimensional quadratic nonlinear photonic crystals with periodic linear and nonlinear susceptibilities. We show that such crystals support stable bright and dark solitons, even when the effective quadratic nonlinearity is zero....

  18. Elementary Particles The first hundred years

    CERN Document Server

    Perkins, Donald Hill

    1997-01-01

    To mark the centenary of the discovery of that first elementary particle, the electron, some remarks and recollections from the early days of high energy physics, including the impact of early experiments and ideas on todayÕs research. Much of our progress in this field has been carefully anticipated and planned, but a surprising number of successes were the result of incredibly lucky breaks, where headway was made despite - or even because of - incorrect experimental results, crossed wires or simply asking the wrong question at the right time. We can be sure therefore that the next century - or perhaps even what remains of this one - will have unexpected surprises in store.

  19. Elementary particle physics in a nutshell

    CERN Document Server

    Tully, Christopher C

    2011-01-01

    The new experiments underway at the Large Hadron Collider at CERN in Switzerland may significantly change our understanding of elementary particle physics and, indeed, the universe. This textbook provides a cutting-edge introduction to the field, preparing first-year graduate students and advanced undergraduates to understand and work in LHC physics at the dawn of what promises to be an era of experimental and theoretical breakthroughs. Christopher Tully, an active participant in the work at the LHC, explains some of the most recent experiments in the field. But this book, which emerged fr

  20. Elementary numerical mathematics for programmers and engineers

    CERN Document Server

    Stoyan, Gisbert

    2016-01-01

    This book covers the basics of numerical methods, while avoiding the definition-theorem-proof style and instead focusing on numerical examples and simple pseudo-codes. The book is divided into ten chapters. Starting with floating number calculations and continuing up to ordinary differential equations, including "Euler backwards". The final chapter discusses practical error estimations. Exercises (including several in MATLAB) are provided at the end of each chapter. Suitable for readers with minimal mathematical knowledge, the book not only offers an elementary introduction to numerical mathematics for programmers and engineers but also provides supporting material for students and teachers of mathematics.

  1. Elementary particles and emergent phase space

    CERN Document Server

    Zenczykowski, Piotr

    2014-01-01

    The Standard Model of elementary particles, although very successful, contains various elements that are put in by hand. Understanding their origin requires going beyond the model and searching for ""new physics"". The present book elaborates on one particular proposal concerning such physics. While the original conception is 50 years old, it has not lost its appeal over time. Its basic idea is that space - an arena of events treated in the Standard Model as a classical background - is a concept which emerges from a strictly discrete quantum layer in the limit of large quantum numbers. This bo

  2. Current experiments in elementary particle physics. Revised

    Energy Technology Data Exchange (ETDEWEB)

    Galic, H. [Stanford Univ., CA (United States). Stanford Linear Accelerator Center; Wohl, C.G.; Armstrong, B. [Lawrence Berkeley Lab., CA (United States); Dodder, D.C. [Los Alamos National Lab., NM (United States); Klyukhin, V.I.; Ryabov, Yu.G. [Inst. for High Energy Physics, Serpukhov (Russian Federation); Illarionova, N.S. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation); Lehar, F. [CEN Saclay, Gif-sur-Yvette (France); Oyanagi, Y. [Univ. of Tokyo (Japan). Faculty of Sciences; Olin, A. [TRIUMF, Vancouver, BC (Canada); Frosch, R. [Paul Scherrer Inst., Villigen (Switzerland)

    1992-06-01

    This report contains summaries of 584 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1986 are excluded. Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, KEK, LAMPF, Novosibirsk, Paul Scherrer Institut (PSI), Saclay, Serpukhov, SLAC, SSCL, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

  3. Elementary polarization properties in the backscattering configuration.

    Science.gov (United States)

    Arteaga, Oriol; Garcia-Caurel, Enric; Ossikovski, Razvigor

    2014-10-15

    In the normal incidence backscattering configuration, a polarimetric measurement always preserves the reciprocal symmetry. For a reciprocal Jones matrix, the number of elementary polarization properties is reduced from six to four. In this work, the physical interpretation of these properties is examined and they are compared with the equivalent polarization properties in transmission. It is found that, with the exception of natural optical activity, a polarimetric backreflection experiment can essentially provide the same type of information about the anisotropy of a medium as a transmission analysis, although transmission and backreflection information comes in a completely different form. Experimental examples are provided to illustrate the discussion.

  4. Current experiments in elementary particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Wohl, C.G.; Armstrong, F.E.; Trippe, T.G.; Yost, G.P. (Lawrence Berkeley Lab., CA (USA)); Oyanagi, Y. (Tsukuba Univ., Ibaraki (Japan)); Dodder, D.C. (Los Alamos National Lab., NM (USA)); Ryabov, Yu.G.; Slabospitsky, S.R. (Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Serpukhov (USSR). Inst. Fiziki Vysokikh Ehnergij); Frosch, R. (Swiss Inst. for Nuclear Research, Villigen (Switzerla

    1989-09-01

    This report contains summaries of 736 current and recent experiments in elementary particle physics (experiments that finished taking data before 1982 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Tokyo Institute of Nuclear Studies, Moscow Institute of Theoretical and Experimental Physics, Joint Institute for Nuclear Research (Dubna), KEK, LAMPF, Novosibirsk, PSI/SIN, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground experiments. Also given are instructions for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

  5. Baryogenesis via Elementary Goldstone Higgs Relaxation

    CERN Document Server

    Gertov, Helene; Pearce, Lauren; Yang, Louis

    2016-01-01

    We extend the relaxation mechanism to the Elementary Goldstone Higgs frame- work. Besides studying the allowed parameter space of the theory we add the minimal ingredients needed for the framework to be phenomenologically viable. The very nature of the extended Higgs sector allows to consider very flat scalar potential directions along which the relaxation mechanism can be implemented. This fact translates into wider regions of applicability of the relaxation mechanism when compared to the Standard Model Higgs case. Our results show that, if the electroweak scale is not fundamental but radiatively generated, it is possible to generate the observed matter-antimatter asymmetry via the relaxation mechanism.

  6. Gas explosions - an elementary account; Eksplosiv fare

    Energy Technology Data Exchange (ETDEWEB)

    Seehusen, Joachim

    2002-07-01

    Although in a typical gas explosion the flame front propagates at sub-sonic speed, it still moves fast. Safety people often believe they can run away from a gas explosion. While gas explosions are well understood in the major companies, this is not true in many small ones, and people often do not realise how small the difference may be between a small puff and a dangerous explosion. Of special interest in a ''hydrogen society'' is the fact that hydrogen is dangerous and must be handled with care. The article discusses in an elementary way some of the basic concepts from the physics of gas explosions.

  7. Elementary reaction allyl radical with oxygen

    Institute of Scientific and Technical Information of China (English)

    DONG Feng; KONG Fanao

    2003-01-01

    The elementary reaction between allyl radical with oxygen molecule wasexperimentally investigated. The allyl radical was produced via laser photolysis of C3H5Br in gaseous phase. Nascent vibrational excited products HCO, CO2, CH3CHO and HCOOH were recorded by the time- resolved Fourier transform infrared spectroscopy. The product channels of C2H5+CO2, CH3CHO+HCO, and HCOOH + C2H3 have been identified. The vibrational populations of product CO2 are obtained by spectral simulation. A mechanism forming a series of three-membered ring-struc- ture intermediates is suggested.

  8. Current experiments in elementary particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Wohl, C.G.; Armstrong, F.E., Oyanagi, Y.; Dodder, D.C.; Ryabov, Yu.G.; Frosch, R.; Olin, A.; Lehar, F.; Moskalev, A.N.; Barkov, B.P.

    1987-03-01

    This report contains summaries of 720 recent and current experiments in elementary particle physics (experiments that finished taking data before 1980 are excluded). Included are experiments at Brookhaven, CERN, CESR, DESY, Fermilab, Moscow Institute of Theoretical and Experimental Physics, Tokyo Institute of Nuclear Studies, KEK, LAMPF, Leningrad Nuclear Physics Institute, Saclay, Serpukhov, SIN, SLAC, and TRIUMF, and also experiments on proton decay. Instructions are given for searching online the computer database (maintained under the SLAC/SPIRES system) that contains the summaries. Properties of the fixed-target beams at most of the laboratories are summarized.

  9. An Elementary Introduction to Statistical Learning Theory

    CERN Document Server

    Kulkarni, Sanjeev

    2011-01-01

    A thought-provoking look at statistical learning theory and its role in understanding human learning and inductive reasoning A joint endeavor from leading researchers in the fields of philosophy and electrical engineering, An Elementary Introduction to Statistical Learning Theory is a comprehensive and accessible primer on the rapidly evolving fields of statistical pattern recognition and statistical learning theory. Explaining these areas at a level and in a way that is not often found in other books on the topic, the authors present the basic theory behind contemporary machine learning and

  10. Resource Letter NO-1: Nonlinear Optics

    Science.gov (United States)

    Garmire, Elsa

    2011-03-01

    This Resource Letter provides a guide to the literature on nonlinear optics. Books, journals, and websites are introduced that cover the general subject. Journal articles and websites are cited covering the following topics: second-order nonlinearities in transparent media including second-harmonic generation and optical parametric oscillation, third-order and higher nonlinearities, nonlinear refractive index, absorptive nonlinearities such as saturable absorption and multiphoton absorption, and scattering nonlinearities such as stimulated Raman scattering and stimulated Brillouin scattering. Steady-state and transient phenomena, fiber optics, solitons, nonlinear wave mixing, optical phase conjugation, nonlinear spectroscopy, and multiphoton microscopy are all outlined.

  11. Elementary particle physics at the University of Florida. Annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-01

    This report discusses research in the following areas: theoretical elementary particle physics; experimental elementary particle physics; axion project; SSC detector development; and computer acquisition. (LSP).

  12. Nonlinear Dynamics: Integrability, Chaos and Patterns

    Energy Technology Data Exchange (ETDEWEB)

    Grammaticos, B [GMPIB, Universite Paris VII, Tour 24--14, 5e etage, Case 7021, 75251 Paris (France)

    2004-02-06

    -locking and b) devil's staircase'. I do not quite grasp the usefulness of such project-like exercises. Projects must be assigned by the person who indeed teaches the course. There are things that I really like a lot in this book. For instance, the section on 'chaos in nonlinear electronic circuits' is particularly interesting. It offers a simple and rather inexpensive way to visualize chaos in the laboratory. The closing section of the book devoted to technological applications of nonlinear dynamics is also quite useful. The fact that the treatment remains rather elementary, based on review articles and monographs rather than research articles, adds to the intelligibility of the chapter, which will certainly prove stimulating to many a student. Of course, not everything can be perfect, and a 600-page book is bound to have some weak points. I find the treatment of quantum chaos rather sketchy and that of chaotic scattering even more so. Also, while the authors are aware of the importance of complex time in integrability, they do not attempt an explanation of the fundamental puzzle: 'why, while the physical time is par excellence real, do we need a complex time in order to study the long-time behaviour of dynamical systems?'. Also the book devotes just four pages to integrable discrete systems. Given the tremendous development of this domain over the past decade, this short presentation is not doing justice to the subject. (However as the present reviewer is editing Springer Lecture Notes in Physics on precisely 'Integrable Discrete Systems', to appear in early 2004, he would be the last one to complain about the absence of more details on the matter in the present book.) To sum it up, the monograph of Lakshmanan and Rajasekar is a book written by physicists and for physicists. It will be of interest to both the experienced practitioner and to the uninitiated. Its main quality resides in its thorough, pedagogical approach to the matter

  13. Elementary Algebra + Student-Written Web Illustrations = Math Mastery.

    Science.gov (United States)

    Veteto, Bette R.

    This project focuses on the construction and use of a student-made elementary algebra tutorial World Wide Web page at the University of Memphis (Tennessee), how this helps students further explore the topics studied in elementary algebra, and how students can publish their work on the class Web page for use by other students. Practical,…

  14. Vector valued logarithmic residues and the extraction of elementary factors

    NARCIS (Netherlands)

    H. Bart (Harm); T. Ehrhardt; B. Silbermann

    2007-01-01

    textabstractAn analysis is presented of the circumstances under which, by the extraction of elementary factors, an analytic Banach algebra valued function can be transformed into one taking invertible values only. Elementary factors are generalizations of the simple scalar expressions λ – α, the bui

  15. Changing Pre-Service Elementary Teachers' Attitudes to Algebra.

    Science.gov (United States)

    McGowen, Mercedes A.; Davis, Gary E.

    This article addresses the question: "What are the implications for the preparation of prospective elementary teachers of 'early algebra' in the elementary grades curriculum?" Part of the answer involves language aspects of algebra: in particular, how a change in pre-service teachers' attitudes to algebra, from instrumental to relational, is…

  16. Roles of Teachers in Orchestrating Learning in Elementary Science Classrooms

    Science.gov (United States)

    Zhai, Junqing; Tan, Aik-Ling

    2015-01-01

    This study delves into the different roles that elementary science teachers play in the classroom to orchestrate science learning opportunities for students. Examining the classroom practices of three elementary science teachers in Singapore, we found that teachers shuttle between four key roles in enabling student learning in science. Teachers…

  17. Using Smart Boards and Manipulatives in the Elementary Science Classroom

    Science.gov (United States)

    Martin, Susan F.; Shaw, Edward L., Jr.; Daughenbaugh, Lynda

    2014-01-01

    This study summarizes the results of a survey administered to 48 elementary schools in the largest school district in a southeastern U.S. state, conducted by university faculty to evaluate the use of SMART Boards and hands-on experiences, the objectives of which were to identify preparedness of elementary classroom teachers in teaching elementary…

  18. Reconceptualizing Elementary Teacher Preparation : A case for informal science education

    NARCIS (Netherlands)

    Avraamidou, Lucy

    2015-01-01

    The purpose of this case study was to explore the ways in which 3 different informal science experiences in the context of an elementary methods course influenced a group of prospective elementary teachers' ideas about science teaching and learning as well as their understandings about the role of

  19. Prospective Elementary Teachers' Development of Fraction Number Sense

    Science.gov (United States)

    Utley, Juliana; Reeder, Stacy

    2012-01-01

    Can prospective elementary teachers "unlearn" harmful algorithms used with fractions as they are invited to develop fraction number sense? This study examined the development of prospective elementary teachers' fraction number sense during an intermediate (grades 5-8) mathematics methods course. During this course, participants' were involved in a…

  20. Reconceptualizing Elementary Teacher Preparation : A case for informal science education

    NARCIS (Netherlands)

    Avraamidou, Lucy

    2015-01-01

    The purpose of this case study was to explore the ways in which 3 different informal science experiences in the context of an elementary methods course influenced a group of prospective elementary teachers' ideas about science teaching and learning as well as their understandings about the role of i