52,953 research outputs found

    Asymptotic Learning Curve and Renormalizable Condition in Statistical Learning Theory

    Full text link
    Bayes statistics and statistical physics have the common mathematical structure, where the log likelihood function corresponds to the random Hamiltonian. Recently, it was discovered that the asymptotic learning curves in Bayes estimation are subject to a universal law, even if the log likelihood function can not be approximated by any quadratic form. However, it is left unknown what mathematical property ensures such a universal law. In this paper, we define a renormalizable condition of the statistical estimation problem, and show that, under such a condition, the asymptotic learning curves are ensured to be subject to the universal law, even if the true distribution is unrealizable and singular for a statistical model. Also we study a nonrenormalizable case, in which the learning curves have the different asymptotic behaviors from the universal law

    Breaking Down the Codes: A Study of the Nonverbal Emblems and Regulators Used in International B-Boy Competitions

    Get PDF
    This study explored the use of nonverbal emblems and regulators in international b-boy competitions. Using semiotics, a lexicon of the emblems and regulators was recorded. Then the dimensions from a theory of semantics of dance were applied to understand how b-boy crews (dance teams) from around the world use gesture to communicate with the audience, judges, and other crews. The study analyzed how culture influences the use of emblems and regulators in the intercultural exchange that occurs during the international b-boy competitions, such as Battle of the Year (BOTY) and R16 World Series. Four videos from the 2013 and 2014 BOTY and 2015 R16 were analyzed. The study concluded that cultural dimensions such as collectivism and indulgence influences emblem selection, intensity, and frequency. These nonverbal elements exhibit an overall impact on the battle and the determination of the winner. The paper upon which this poster was based was written for the Senior Seminar course in Communication Arts. The paper was competitively selected for presentation at the Northwest Communication Association Conference in April 2016

    Adsorbent phosphates

    Get PDF
    An adsorbent which uses as its primary ingredient phosphoric acid salts of zirconium or titanium is presented. Production methods are discussed and several examples are detailed. Measurements of separating characteristics of some gases using the salts are given

    Chemical Evolution in the Large Magellanic Cloud

    Get PDF
    We present a new input parameter set of the Pagel model (Pagel & Tautvais˘\rm \breve{s}iene˙\rm \dot{e} 1998) for the Large Magellanic Cloud (LMC) in order to reproduce the observations, including the star formation rate (SFR) history. It is concluded that the probability for (3-8)M⊙M_{\odot} stars to explode as SNe Ia has to be quite high (∼0.17\sim 0.17) in the LMC. As a result, a steep initial mass function (IMF) slope and existence of the outflow are not needed in order to attain the low [O/Fe] ratio in the LMC. As for the current supernova ratio, a high ratio (∼1.3\sim 1.3) is concluded by the new parameter set, which is consistent with the recent X-ray observations.Comment: 20 pages, gzipped tar file including LaTeX text and 8 postscript figures. submitted to Publication of the Astronomical Society of Japa

    \delta N versus covariant perturbative approach to non-Gaussianity outside the horizon in multifield inflation

    Full text link
    We compute the super-Hubble evolution of non-Gaussianity of primordial curvature perturbations in two-field inflation models by employing two formalisms: delta N and covariant formalisms. Although two formalisms treat the evolution of fluctuations radically different, we show that the formulas of f_{NL} parameter agree quantitatively with each other within 1 % accuracy. We analytically find that the amplitude of f_{NL} decays no faster than a^{-3} as the inflationary trajectory reaches to the adiabatic limit for generic potentials.Comment: v4: minor changes, version accepted for PRD; v3: 10 pages, 14 figures, added two examples that produce relatively large non-Gaussianity in Appendix to support the results; v2: 8 pages, 10 figures, added reference

    Constraining the Cosmic Star Formation Rate with the MeV Background

    Get PDF
    The Cosmic Gamma-ray Background (CGB) in the MeV regime has been measured with COMPTEL and SMM. The origin of the CGB in this energy regime is believed to be dominated by gamma-rays from Type Ia supernovae. We calculate the CGB spectrum within the framework of FRW cosmology as a function of the cosmic star formation rate, SFR(z). Several estimates of the SFR(z) have been reported since the pioneering work of Madau et al. Here we discuss observational constraints on SFR(z) derived from models of the CGB. In particular, we consider the SFR obtained from Gamma-Ray Burst observations, which increases dramatically with redshift beyond z ~ 1 in contrast to most estimates which saturate or show a mild increase with redshift. Gamma-ray bursts may be the most powerful tracers of star formation in the early universe and thus provide signposts of the initial epoch of element synthesis. The star formation rate implied by GRB statistics results in a gamma-ray background that matches the observations more closely than that inferred from other tracers of star formation. This may provide some support for the GRB/SFR-paradigm, which in turn promises a powerful diagnostic of star formation, and thus cosmic chemical evolution, from the era of Population III stars to the present

    Amplification of Quantum Meson Modes in the Late Time of Chiral Phase Transition

    Full text link
    It is shown that there exists a possibility of amplification of amplitudes of quantum pion modes with low momenta in the late time of chiral phase transition by using the Gaussian wave functional approximation in the O(4) linear sigma model. It is also shown that the amplification occurs in the mechanism of the resonance by forced oscillation as well as the parametric resonance induced by the small oscillation of the chiral condensate. These mechanisms are investigated in both the case of spatially homogeneous system and the spatially expanded system described by the Bjorken coordinate.Comment: 17 pages, 16 figure

    Electronic Transport in Fullerene C20 Bridge Assisted by Molecular Vibrations

    Full text link
    The effect of molecular vibrations on electronic transport is investigated with the smallest fullerene C20 bridge, utilizing the Keldysh nonequilibrium Green's function techniques combined with the tight-binding molecular-dynamics method. Large discontinuous steps appear in the differential conductance when the applied bias-voltage matches particular vibrational energies. The magnitude of the step is found to vary considerably with the vibrational mode and to depend on the local electronic states besides the strength of electron-vibration coupling. On the basis of this finding, a novel way to control the molecular motion by adjusting the gate voltage is proposed.Comment: 9 pages, 4 figures, accepted for publication in Phys. Rev. Let
    • …
    corecore