A one-dimensional quantum hydrodynamic model （or quantum Euler-Poisson system） for semiconductors with initial boundary conditions is considered for general pressure-density function. The existence and uniqueness of...
详细信息
A one-dimensional quantum hydrodynamic model （or quantum Euler-Poisson system） for semiconductors with initial boundary conditions is considered for general pressure-density function. The existence and uniqueness of the classical solution of the corresponding steady-state quantum hydrodynamic equations is proved. Furthermore, the global existence of classical solution, when the initial datum is a perturbation of t he steadystate solution, is obtained. This solution tends to the corresponding steady-state solution exponentially fast as the time tends to infinity.
By the uniform a priori estimate of solution about parameters, we prove the existence of global solution and inviscid lim- it to a generalized Ginzburg-Landau equations in two dimensions. We also prove that the soluti...
详细信息
By the uniform a priori estimate of solution about parameters, we prove the existence of global solution and inviscid lim- it to a generalized Ginzburg-Landau equations in two dimensions. We also prove that the solution to the Ginzburg-Landau equations converges to the weak solution to the derivative nonlinear Schrodinger equations.
We prove that n-dimensional radial symmetric Landau-Lifshitz equation possesses at least two classes of global smooth solutions with suitable initial-boundary conditions.
We prove that n-dimensional radial symmetric Landau-Lifshitz equation possesses at least two classes of global smooth solutions with suitable initial-boundary conditions.
Using the gravitational torque indicator Qb, we derive the distribution of bar strengths for a sample of early-type disk galaxies. The sample is part of the Near-Infrared S0 Survey (NIRS0S), designed to examine the pr...
详细信息
Using the gravitational torque indicator Qb, we derive the distribution of bar strengths for a sample of early-type disk galaxies. The sample is part of the Near-Infrared S0 Survey (NIRS0S), designed to examine the properties of bars, bulges, and disks in galaxies classified as types S0− to Sa. Although the survey is only partly finished, we find that the distribution of bar strengths in S0 galaxies differs from that in spirals by lacking an extended tail to high values of Qb. No S0 in our current sample has Qb > 0.25, while spirals extend to Qb ≈ 0.7. Bars having Qb > 0.25 first appear among S0/a to Sa galaxies.
A description of the so called "particles with coupled oscillator dynamics" (PCOD) is presented which is used to model, analyze and synthesize collective motion. An oscillator model with spatial dynamics is ...
详细信息
A description of the so called "particles with coupled oscillator dynamics" (PCOD) is presented which is used to model, analyze and synthesize collective motion. An oscillator model with spatial dynamics is presented to help describe how to design steering control laws while it is being used to study biological collectives. Lastly, both engineering and biological analysis were described.
Using the single electron model, the acceleration of electrons in combined circularly polarized intense laser fields and the spontaneous quasistatic fields （including axial and azimuthal magnetic fields, the axial an...
详细信息
Using the single electron model, the acceleration of electrons in combined circularly polarized intense laser fields and the spontaneous quasistatic fields （including axial and azimuthal magnetic fields, the axial and transverse electric fields） produced in intense laser plasma interaction is investigated analytically and numerically by fitting the proper parameters of the quasistatic fields based on the data from the experiment and numerical calculation. A new resonant condition is given. It is found that the resonance acceleration of electron depends not only on laser field, but also on the bounce frequency oscillating in the quasistatic magnetic field and electric field. The net energy gained by electron does not increase monotonously with axial electric field, but there are some optimal axial electric fields.
We study an atomic Bose-Fermi mixture with unpolarized fermions in an optical lattice. We obtain the Mott ground states of such a system in the limit of the deep optical lattice and discuss the effect of quantum fluct...
详细信息
We study an atomic Bose-Fermi mixture with unpolarized fermions in an optical lattice. We obtain the Mott ground states of such a system in the limit of the deep optical lattice and discuss the effect of quantum fluctuations on these states. We also study the superfluid-insulator transitions of bosons and metal-insulator transition of fermions in such a mixture within a slave-rotor mean-field approximation, and obtain the corresponding phase diagram. We discuss experimental implications of our results.
In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abs...
详细信息
In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.
The effects of transverse temperature distribution on the Weibel instability in a laser produced plasma are studied analytically by using a three dimensional waterbag model. It is found that the purely transverse Weib...
详细信息
The effects of transverse temperature distribution on the Weibel instability in a laser produced plasma are studied analytically by using a three dimensional waterbag model. It is found that the purely transverse Weibel instability can be stabilized for the case in which the electron beam has a more symmetric transverse temperature distribution. This analytical expectation is supported by our two dimensional particle-in-cell simulations.
Boundary conditions for molecular dynamics simulation of crystalline solids are considered with the objective of eliminating the reflection of phonons.A variational formalism is presented to construct boundary conditi...
详细信息
Boundary conditions for molecular dynamics simulation of crystalline solids are considered with the objective of eliminating the reflection of phonons.A variational formalism is presented to construct boundary conditions that minimize total phonon *** boundary conditions that involve a few neighbors of the boundary atoms and limited number of time steps are found using the variational *** effects are studied and compared with other boundary conditions such as truncated exact boundary conditions or by appending border atoms where artificial damping forces are *** general it is found that,with the same cost or complexity,the variational boundary conditions perform much better than the truncated exact boundary conditions or by appending border atoms with empirical damping *** issues of implementation are discussed for real *** to brittle fracture dynamics is illustrated.
暂无评论