41,820 research outputs found

    Stability and asymptotic behavior of periodic traveling wave solutions of viscous conservation laws in several dimensions

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    Under natural spectral stability assumptions motivated by previous investigations of the associated spectral stability problem, we determine sharp LpL^p estimates on the linearized solution operator about a multidimensional planar periodic wave of a system of conservation laws with viscosity, yielding linearized L1LpLpL^1\cap L^p\to L^p stability for all p2p \ge 2 and dimensions d1d \ge 1 and nonlinear L1HsLpHsL^1\cap H^s\to L^p\cap H^s stability and L2L^2-asymptotic behavior for p2p\ge 2 and d3d\ge 3. The behavior can in general be rather complicated, involving both convective (i.e., wave-like) and diffusive effects

    Influence of external disturbances and compressibility on free turbulent mixing

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    It is shown that disturbances in external flow can significantly affect, by as much as an order of magnitude, the turbulent mixing rate in free shear layers and that the length scale of the external flow disturbances is as important as the amplitude. The difference between the effect of wide-band and narrow-band disturbances is stressed. The model for pressure fluctuation term in the kinetic energy equation is included in a two-equation model. The reduced spreading rate in high Mach number, high Reynolds number, adiabatic, free turbulent shear layers is predicted

    Symplectic Reduction and Symmetry Algebra in Boundary Chern-Simons theory

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    We derive the Kac-Moody algebra and Virasoro algebra in Chern-Simons theory with boundary by using the symplectic reduction method and the Noether procedures.Comment: References are adde

    Is perception of destination image stable or does it fluctuate? A measurement of three points in time

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    This study aimed to identify variations of three types of perceived image including affective, cognitive, and overall image over three points in time and to test the efficacy of image in explaining satisfaction, knowledge, and attachment with a destination. Although previous studies used results collected through a cross-sectional survey, this study surveyed the same samples at three different times, that is before, during and after travel, to enrich our understanding of how image develops through the three key stages of a trip. The findings indicate there is significant variation in perceived image domains, extracted as a result of factor analysis, and overall image across time. To predict satisfaction, attachment, and knowledge, “vividness” of the affective image domains and “diverse tourism attraction” of the cognitive image domains showed significance on regression models. Interestingly, “developed tourism industry” was not reported being significant predictor in any model. The results suggest that future studies need to measure destination image over time in line with traveller’s movement

    Greenberger-Horne-Zeilinger paradoxes from qudit graph states

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    One fascinating way of revealing the quantum nonlocality is the all-versus-nothing test due to Greenberger, Horne, and Zeilinger (GHZ) known as GHZ paradox. So far genuine multipartite and multilevel GHZ paradoxes are known to exist only in systems containing an odd number of particles. Here we shall construct GHZ paradoxes for an arbitrary number (greater than 3) of particles with the help of qudit graph states on a special kind of graphs, called as GHZ graphs. Based on the GHZ paradox arising from a GHZ graph, we derive a Bell inequality with two dd-outcome observables for each observer, whose maximal violation attained by the corresponding graph state, and a Kochen-Specker inequality testing the quantum contextuality in a state-independent fashion

    Testing tripartite Mermin inequalities by spectral joint-measurements of qubits

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    It is well known that Bell inequality supporting the local realism can be violated in quantum mechanics. Numerous tests of such a violation have been demonstrated with bipartite entanglements. Using spectral jointmeasurements of the qubits, we here propose a scheme to test the tripartite Mermin inequality (a three-qubit Bell-type inequality) with three qubits dispersively-coupled to a driven cavity. First, we show how to generate a three-qubit Greenberger-Horne-Zeilinger (GHZ) state by only one-step quantum operation. Then, spectral joint-measurements are introduced to directly confirm such a tripartite entanglement. Assisted by a series of single-qubit operations, these measurements are further utilized to test the Mermin inequality. The feasibility of the proposal is robustly demonstrated by the present numerical experiments.Comment: 7pages,3figure

    Quantum cryptography based on qutrit Bell inequalities

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    We present a cryptographic protocol based upon entangled qutrit pairs. We analyze the scheme under a symmetric incoherent attack and plot the region for which the protocol is secure and compare this with the region of violations of certain Bell inequalities
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