In this paper,we study the initial-boundary value problem of one class of nonlinear Schr(o)dinger equations described in molecular ***,the existence of the global solution is obtained by means of interpolation inequal...
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In this paper,we study the initial-boundary value problem of one class of nonlinear Schr(o)dinger equations described in molecular ***,the existence of the global solution is obtained by means of interpolation inequality and a priori estimation.
It is known that ion channel can effectively limit the radial expansion of an artificial electron beam during its longrange propagation in the space plasma *** prior studies discussed the focusing characteristics of t...
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It is known that ion channel can effectively limit the radial expansion of an artificial electron beam during its longrange propagation in the space plasma *** prior studies discussed the focusing characteristics of the beam in the ion channel,but the establishment process and transient properties of the ion channel itself,which also plays a crucial role during the propagation of the relativistic electron beam in the plasma environment,were commonly *** this study,a series of two-dimensional(2D)particle-in-cell simulations is performed and an analytical model of ion channel oscillation is constructed according to the single-particle *** results showed that when the beam density is higher than the density of plasma environment,ion channel can be established and always continues to oscillate periodically over the entire *** factors,including the beam electron density,initial beam radius,and the plasma density can affect the oscillation properties of ion *** velocity of the beam oscillates synchronously with the ion channel and this phenomenon will finally develop into a two-stream instability which can seriously affect the effective transport for relativistic electron *** appropriate beam parameters based on various plasma environments may contribute to the improvement of the stability of ion ***,radial expansion of the beam can be limited by ion channel and a stable long-range propagation in terrestrial atmosphere may be achieved.
In this paper, we consider the three-dimensional isentropic compressible fluid models of Korteweg type, called the compressible Navier-Stokes-Korteweg system. We mainly present the vanishing capillarity limit of the s...
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It is known that ion-focused regime(IFR)can effectively suppress expansion of a relativistic electron beam(REB).Using the particle-in-cell Monte Carlo collision(PIC-MCC)method,we numerically investigate the propagatio...
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It is known that ion-focused regime(IFR)can effectively suppress expansion of a relativistic electron beam(REB).Using the particle-in-cell Monte Carlo collision(PIC-MCC)method,we numerically investigate the propagation of an REB in neutral *** results demonstrate that the beam body is charge neutralization and a stable IFR can be *** a result,the beam transverse dimensions and longitudinal velocities keep close to the initial *** also calculate the charge and current neutralization factors of the *** with envelope equations,we obtain the variations of beam envelopes,which agree well with the PIC ***,both the energy loss and instabilities of the REB may lead to a low transport efficiency during long-range *** is proved that decreasing the initial pulse length of the REB can avoid the influence of electron *** parts of REB pulses to build a long-distance IFR in advance can improve the beam quality of subsequent ***,a long-distance IFR may contribute to the implementation of long-range propagation of the REB in space environment.
We present two time integration algorithms with second-order accuracy for nonlinear elastodynamics. The first algorithm is a two-parameter family blending the second-order and third-order backward differentiation form...
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Existing schemes for demonstrating quantum computational advantage are subject to various practical restrictions, including the hardness of verification and challenges in experimental implementation. Meanwhile, analog...
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Existing schemes for demonstrating quantum computational advantage are subject to various practical restrictions, including the hardness of verification and challenges in experimental implementation. Meanwhile, analog quantum simulators have been realized in many experiments to study novel physics. In this work, we propose a quantum advantage protocol based on single-step Feynman-Kitaev verification of an analog quantum simulation, in which the verifier need only run an O(λ2)-time classical computation, and the prover need only prepare O(1) samples of a history state and perform O(λ2) single-qubit measurements, for a security parameter λ. We also propose a near-term feasible strategy for honest provers and discuss potential experimental realizations.
We describe a new family of discrete spaces suitable for use with mixed methods on certain quadrilateral and hexahedral meshes. The new spaces are natural in the sense of differential geometry, so all the usual mixed ...
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We present several observations on spiral turbulence based on three-dimensional direct numerical simulations of a Taylor-Couette system at three Reynolds numbers. The flow is characteristized by patterns of alternatin...
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ISBN:
(纸本)9781600867392
We present several observations on spiral turbulence based on three-dimensional direct numerical simulations of a Taylor-Couette system at three Reynolds numbers. The flow is characteristized by patterns of alternating helical bands, with possibly different helicities at different Reynolds numbers, of laminar and turbulent fluids that propagate between the cylinders. The region that the turbulent spiral sweeps through is observed to be radially closer to the outer cylinder than to the inner one.
A weakly nonlinear model is proposed for the Kelvin-Helmholtz instability in two-dimensional incompressible fluids by expanding the perturbation velocity potential to third order. The third-order harmonic generation e...
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A weakly nonlinear model is proposed for the Kelvin-Helmholtz instability in two-dimensional incompressible fluids by expanding the perturbation velocity potential to third order. The third-order harmonic generation effects of single-mode perturbation are analyzed, as well as the nonlinear correction to the exponential growth of the fundamental modulation. The weakly nonlinear results are supported by numerical simulations. Density and resonance effects exist in the development of mode coupling.
A discussion of the cross-spectral properties of eddies in the lowest 40 m of the nocturnal boundary layer is presented. The study involves the analysis of meteorological data collected by the British Antarctic Survey...
A discussion of the cross-spectral properties of eddies in the lowest 40 m of the nocturnal boundary layer is presented. The study involves the analysis of meteorological data collected by the British Antarctic Survey at Halley Station, Antarctica, during the austral winter of 1986. Cross-spectral analysis is used to determine whether the nature of the observed eddies is primarily turbulent or whether their structure is characteristic of coherent internal gravity waves. It is found that the cross-spectral phases indicate the presence of turbulent eddies only when the local gradient Richardson number (Ri) is less than the critical value of 1/4. Trapped modes were only observed when an offshore wind prevailed, indicating that topographic effects are responsible for their generation. The relative phases of velocity and temperature were often observed to change with height. This can be explained by examining the underlying meteorological conditions. On several occasions, regions of counter-gradient fluxes were detected. A physical explanation of this phenomenon is proposed.
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