2,277 research outputs found

    Varying-coefficient modeling via regularized basis functions

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    We address the problem of constructing varying-coefficient models based on basis expansions along with the technique of regularization. A crucial point in our modeling procedure is the selection of smoothing parameters in the regularization method. In order to choose the parameters objectively, we derive model selection criteria from the viewpoints of information-theoretic and Bayesian approach. We demonstrate the effectiveness of proposed modeling strategy through Monte Carlo simulations and analyzing a real data set.Comment: 10 pages, 4 figure

    Early Ontogeny of the Japanese Common Squid Todarodes pacificus (Cephalopoda, Ommastrephidae) with Special Reference to its Characteristic Morphology and Ecological Significance

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    Early ontogeny of the Japanese Common Squid Todarodes pacificus was described for artificially inseminated and collected specimens to present new criteria for developmental stages in relation to its ecological adaptation. For the purpose, details for formation of the following organs and tissues were observed with special attention: cilia on the integument, mouth part, shell sac and stellate ganglia, visceral mass, funnel-collar complex, statocysts, eye parts, and ventral photosensitive vesicles. At the embryonic stage (i.e., pre-hatching), various types of epidermal cilia that seem to work as the embryonic rotation were detected. At the early postembryonic stage (i.e., post-hatching), the epidermal lines were characteristically arranged at the scattered condition on arms, tentacles, head, and funnel. Novel strong muscle fibers were distinct in the base of tentacles and funnel retractor muscles at the early postembryonic stage, which is clearly related to the head withdrawal behavior of the paralarvae. The lip cilia and toothed beak developed at the early postembryonic stage, but disappeared later; these apparatus were considered to be related with a change of unique feeding mode in the paralarval life. Based on such morphological features, four distinct stages, namely, paralarval stage 1, 2, 3, and juvenile stage are proposed. The present observations are discussed in relation to survival strategy at early life of T. pacificus and they are compared with those in other cephalopods

    Experimental Research on Performances of Air Turbines for a Fixed Oscillating Water Column-Type Wave Energy Converter

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    A fixed oscillating water column (OWC)-type wave energy converter is composed of an air chamber for primary conversion and an air turbine for secondary conversion. In the optimal design method of a fixed OWC-type wave energy converter, it is necessary to develop a design method which can consider the characteristics of incident wave motion, the motion of the internal free surface affected in the structure such as a partly submerged wall, the fluctuation of air pressure in an air chamber, the rotation of the air turbine. In this paper, the 2-dimensional wave tank tests in regular waves for the performance evaluation of the air turbines in a fixed OWC-type wave energy converter were conducted to obtain the data needed to make this design method. As the results, the effects of the impulse turbine specification such as the rotor inlet/outlet angle, the guide vane's number and the vane's setting angle on the primary and secondary conversion efficiencies are clarified experimentally. Furthermore, the performances of the Wells turbines with different number of blade are presented for comparison of the operating condition

    Topological nature of polarization and charge pumping in ferroelectrics

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    Electric polarization or transferred charge due to an adiabatic change of external parameters Q\vec{Q} is expressed in terms of a vector field defined in the Q\vec{Q} space. This vector field is characterized by strings, i.e., trajectories of band-crossing points. In particular, the transverse component is given by the Biot-Savart law in a nonlocal way. For a cyclic change of Q\vec{Q} along a loop C, the linking number between this string and C represents the amount of the pumped charge, which is quantized to be an integer as discussed by Thouless.Comment: 5 pages including 4 figure

    The asymptotic behavior of globally smooth solutions of bipolar non-isentropic compressible Euler-Maxwell system for plasma

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    The bipolar non-isentropic compressible Euler-Maxwell system is investigated in R3R^3 in the present paper, and the LqL^q time decay rate for the global smooth solution is established. It is shown that the total densities, total temperatures and magnetic field of two carriers converge to the equilibrium states at the same rate (1+t)3/2+3q/2(1+t)^{-3/2+3q/2} in LqL^q norm. But, both the difference of densities and the difference of temperatures of two carriers decay at the rate (1+t)21q(1+t)^{-2-\frac{1}{q}}, and the velocity and electric field decay at the rate (1+t)3/2+12q(1+t)^{-3/2+\frac{1}{2q}}. This phenomenon on the charge transport shows the essential difference between the non-isentropic unipolar Euler-Maxwell and the bipolar isentropic Euler-Maxwell system.Comment: 27page

    Strict Limit on CPT Violation from Polarization of Gamma-Ray Bursts

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    We report the strictest observational verification of CPT invariance in the photon sector, as a result of gamma-ray polarization measurement of distant gamma-ray bursts (GRBs), which are brightest stellar-size explosions in the universe. We detected the gamma-ray polarization of three GRBs with high significance, and the source distances may be constrained by a well-known luminosity indicator for GRBs. For the Lorentz- and CPT-violating dispersion relation E_{\pm}^2=p^2 \pm 2\xi p^3/M_{Pl}, where \pm denotes different circular polarization states of the photon, the parameter \xi is constrained as |\xi|<O(10^{-15}). Barring precise cancellation between quantum gravity effects and dark energy effects, the stringent limit on the CPT-violating effect leads to the expectation that quantum gravity presumably respects the CPT invariance.Comment: 4 pages; accepted for publication in Physical Review Letters; redshift estimates of GRBs changed (i.e z=0.382 was wrong for GRB 110721A) and calculations of \xi limit improved from the previous versio

    Embodied responses to musical experience detected by human bio-feedback brain features in a geminoid augmented architecture

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    This paper presents the conceptual framework for a study of musical experience and the associated architecture centred on Human-Humanoid Interaction (HHI). On the grounds of the theoretical and experimental literature on the biological foundation of music, the grammar of music perception and the perception and feeling of emotions in music hearing, we argue that music cognition is specific and that it is realized by a cognitive capacity for music that consists of conceptual and affective constituents. We discuss the relationship between such constituents that enables understanding, that is extracting meaning from music at the different levels of the organization of sounds that are felt as bearers of affects and emotions. To account for the way such cognitive mechanisms are realized in music hearing and extended to movements and gestures we bring in the construct of tensions and of music experience as a cognitive frame. Finally, we describe the principled approach to the design and the architecture of a BCI-controlled robotic system that can be employed to map and specify the constituents of the cognitive capacity for music as well as to simulate their contribution to music meaning understanding in the context of music experience by displaying it through the Geminoid robot movements

    Global classical solutions for partially dissipative hyperbolic system of balance laws

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    This work is concerned with (NN-component) hyperbolic system of balance laws in arbitrary space dimensions. Under entropy dissipative assumption and the Shizuta-Kawashima algebraic condition, a general theory on the well-posedness of classical solutions in the framework of Chemin-Lerner's spaces with critical regularity is established. To do this, we first explore the functional space theory and develop an elementary fact that indicates the relation between homogeneous and inhomogeneous Chemin-Lerner's spaces. Then this fact allows to prove the local well-posedness for general data and global well-posedness for small data by using the Fourier frequency-localization argument. Finally, we apply the new existence theory to a specific fluid model-the compressible Euler equations with damping, and obtain the corresponding results in critical spaces.Comment: 39 page

    Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase

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    Phase transitions between the quantum spin Hall and the insulator phases in three dimensions are studied. We find that in inversion-asymmetric systems there appears a gapless phase between the quantum spin Hall and insulator phases in three dimensions, which is in contrast with the two-dimensional case. Existence of this gapless phase stems from a topological nature of gapless points (diabolical points) in three dimensions, but not in two dimensions.Comment: 16 pages, 5 figure
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