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In an Ocean or a River:Bilinear Auto-Backlund Transformations and Similarity Reductions on an Extended Time-Dependent(3+1)-Dimensional Shallow Water Wave Equation 被引量:1
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第1期160-165,共6页
With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic... With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic computation,we find out,on one hand,a set of bilinear auto-Backlund transformations,which could connect certain solutions of that equation with other solutions of that equation itself,and on the other hand,a set of similarity reductions,which could go from that equation to a known ordinary differential equation.The results in this paper depend on all the oceanic variable coefficients in that equation. 展开更多
关键词 OCEAN RIVER extended time-dependent(3+1)-dimensional shallow water wave equation bilinear auto-Bäcklund transformation similarity reduction symbolic computation
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THE FINITE DIFFERENCE STREAMLINE DIFFUSION METHODS FOR TIME-DEPENDENT CONVECTION-DIFFUSION EQUATIONS 被引量:6
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作者 孙澈 沈慧 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1998年第1期72-85,共14页
In this paper, two finite difference streamline diffusion (FDSD) schemes for solving two-dimensional time-dependent convection-diffusion equations are constructed. Stability and optimal order error estimati-ions for c... In this paper, two finite difference streamline diffusion (FDSD) schemes for solving two-dimensional time-dependent convection-diffusion equations are constructed. Stability and optimal order error estimati-ions for considered schemes are derived in the norm stronger than L^2-norm. 展开更多
关键词 time-dependent CONVECTION-DIFFUSION equations STREAMLINE diffusion methods Euler-FDSD SCHEME Crank-Nicolson-FDSD scheme.
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MULTIPLICITY AND CONCENTRATION BEHAVIOUR OF POSITIVE SOLUTIONS FOR SCHRDINGER-KIRCHHOFF TYPE EQUATIONS INVOLVING THE p-LAPLACIAN IN R^N 被引量:4
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作者 贾慧芳 李工宝 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期391-418,共28页
In this article, we study the multiplicity and concentration behavior of positive solutions for the p-Laplacian equation of SchrSdinger-Kirchhoff type -εpM(εp-N∫RN|△u|p)△pu+v(x|u|p-2u=f(u)in RN, where ... In this article, we study the multiplicity and concentration behavior of positive solutions for the p-Laplacian equation of SchrSdinger-Kirchhoff type -εpM(εp-N∫RN|△u|p)△pu+v(x|u|p-2u=f(u)in RN, where △p is the p-Laplacian operator, 1 〈 p 〈 N, M : R+ → R+ and V : RN →R+ are continuous functions, ε is a positive parameter, and f is a continuous function with subcritical growth. We assume that V satisfies the local condition introduced by M. del Pino and P. Felmer. By the variational methods, penalization techniques, and Lyusternik- Schnirelmann theory, we prove the existence, multiplicity, and concentration of solutions for the above equation. 展开更多
关键词 SchrSdinger-Kirchhoff type equation variational methods multiple positive solutions concentrating solution penalization method
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Approximate solution to the time-dependent Kratzer plus screened Coulomb potential in the Feinberg–Horodecki equation 被引量:2
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作者 Mahmoud Farout Ramazan Sever Sameer MIkhdair 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期90-97,共8页
We obtain the quantized momentum eigenvalues Pn together with space-like coherent eigenstates for the space-like counterpart of the Schr¨odinger equation,the Feinberg–Horodecki equation,with a combined Kratzer p... We obtain the quantized momentum eigenvalues Pn together with space-like coherent eigenstates for the space-like counterpart of the Schr¨odinger equation,the Feinberg–Horodecki equation,with a combined Kratzer potential plus screened coulomb potential which is constructed by temporal counterpart of the spatial form of these potentials.The present work is illustrated with two special cases of the general form:the time-dependent modified Kratzer potential and the time-dependent screened Coulomb potential. 展开更多
关键词 quantized momentum states Feinberg-Horodecki equation the time-dependent screened Coulomb potential and time-dependent modified Kratzer potential
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Comparative study of photoionization of atomic hydrogen by solving the one-and three-dimensional time-dependent Schrödinger equations 被引量:2
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作者 Shun Wang Shahab Ullah Khan +2 位作者 Xiao-Qing Tian Hui-Bin Sun Wei-Chao Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期327-336,共10页
We develop a numerical scheme for solving the one-dimensional(1D)time-dependent Schrödinger equation(TDSE),and use it to study the strong-field photoionization of the atomic hydrogen.The photoelectron energy spec... We develop a numerical scheme for solving the one-dimensional(1D)time-dependent Schrödinger equation(TDSE),and use it to study the strong-field photoionization of the atomic hydrogen.The photoelectron energy spectra obtained for pulses ranging from XUV to near infrared are compared in detail to the spectra calculated with our well-developed code for accurately solving the three-dimensional(3D)TDSE.For XUV pulses,our discussions cover intensities at which the ionization is in the perturbative and nonperturbative regimes.For pulses of 400 nm or longer wavelengths,we distinguish the multiphoton and tunneling regimes.Similarities and discrepancies between the 1D and 3D calculations in each regime are discussed.The observed discrepancies mainly originate from the differences in the transition matrix elements and the energy level structures created in the 1D and 3D calculations. 展开更多
关键词 time-dependent Schrodinger equation(TDSE) strong-field ionization photoelectron spectra dynamic interference
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ON THE CONCENTRATION PROPERTIES FOR THE NONLINEAR SCHRDINGER EQUATION WITH A STARK POTENTIAL 被引量:1
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作者 朱世辉 张健 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1923-1938,共16页
In this paper, we study blow-up solutions of the Cauchy problem to the L2 critical nonlinear Schrdinger equation with a Stark potential. Using the variational characterization of the ground state for nonlinear Schrdin... In this paper, we study blow-up solutions of the Cauchy problem to the L2 critical nonlinear Schrdinger equation with a Stark potential. Using the variational characterization of the ground state for nonlinear Schrdinger equation without any potential, we obtain some concentration properties of blow-up solutions, including that the origin is the blow-up point of the radial blow-up solutions, the phenomenon of L2-concentration and rate of L2-concentration of blow-up solutions. 展开更多
关键词 nonlinear Schrdinger equation blow-up solution blow-up point L2-concentration concentration compact principle
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A Finite-Difference Approach to the Time-Dependent Mild-Slope Equation 被引量:1
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作者 张洪生 赵红军 时钟 《China Ocean Engineering》 SCIE EI 2007年第1期65-76,共12页
A finite-difference approach is used to develop a time-dependent mild-slope equation incorporating the effects of bottom dissipation and nonlinearity. The Enler predietor-corrector method and the three-point finite-di... A finite-difference approach is used to develop a time-dependent mild-slope equation incorporating the effects of bottom dissipation and nonlinearity. The Enler predietor-corrector method and the three-point finite-difference method with varying spatial steps are adopted to discretize the time derivatives and the two-dimensional horizontal ones, respectively, thus leading both the time and spatial derivatives to the second-order accuracy. The boundary conditions for the present model are treated on the basis of the general conditions for open and fixed boundaries with an arbitrary reflection coefficient and phase shift. Both the linear and nonlinear versions of the numerical model are applied to the wave propagation and transformation over an elliptic shoal on a sloping beach, respectively, and the linear version is applied to the simulation of wave propagation in a fully open rectangular harbor. From comparison of numerical results with theoretical or experimental ones, it is found that they are in reasonable agreement. 展开更多
关键词 time-dependent mild-slope equation finite-difference approach varying steps NONLINEARITY
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Parametric Equation of Stress Concentration Factor for Circular X-Joints Under Axial Loads 被引量:1
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作者 曲淑英 张国栋 +1 位作者 张宝峰 王心健 《China Ocean Engineering》 SCIE EI 2007年第1期51-64,共14页
In engineering practice, tubular X-joints have been widely used in offshore structures. The fatigue failure of tubular X-joints in offshore engineering is mainly caused by axial tensile stress. In this study, the stre... In engineering practice, tubular X-joints have been widely used in offshore structures. The fatigue failure of tubular X-joints in offshore engineering is mainly caused by axial tensile stress. In this study, the stress concentration factor distribution along the weld toe in the hot spot stress region for tubular X-joints subject to axial loads have been analyzed by use of finite element method. Through numerical analysis, it has been found that the peak stress concentration factor is located at the saddle position. Thereafter, 80 models have been analyzed, and the effect of the geometric parameters of a tubular X-joint on the stress concentration factor has been investigated. Based on the experimental values of the numerical stress concentration factor, a parametric equation to calculate the stress concentration factor of tubular X-joints has been proposed. The accuracy of this equation has been verified against the requirement of the Fatigue Guidance Review Panel, and the proposed equation is found capable of producing reasonably accurate stress concentration factor values for tubular X-joints subject to axial loads. 展开更多
关键词 stress concentration factor SCF S-N curves hot spot stress range HSSR tubular X-joints axialloads parametric equation
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Influence of Auxiliary Equation on Wave Functions for Time-Dependent Pauli Equation in Presence of Aharonov-Bohm Effect 被引量:1
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作者 M.Maamache C.Lahoulou Y.Saadi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期803-810,共8页
Invariant operator method for discrete or continuous spectrum eigenvalue and unitary transformation approach are employed to study the two-dimensional time-dependent Pauli equation in presence of the Aharonov-Bohm eff... Invariant operator method for discrete or continuous spectrum eigenvalue and unitary transformation approach are employed to study the two-dimensional time-dependent Pauli equation in presence of the Aharonov-Bohm effect (AB) and external scalar potential. For the spin particles the problem with the magnetic field is that it introduces a singularity into wave equation at the origin. A physical motivation is to replace the zero radius flux tube by one of radius R, with the additional condition that the magnetic field be confined to the surface of the tube, and then taking the limit R → 0 at the end of the computations. We point that the invariant operator must contain the step function θ(r - R). Consequently, the problem becomes more complicated. In order to avoid this dimculty, we replace the radius R by ρ(t)R, where ρ(t) is a positive time-dependent function. Then at the end of calculations we take the limit R →0. The qualitative properties for the invariant operator spectrum are described separately for the different values of the parameter C appearing in the nonlinear auxiliary equation satisfied by p(t), i.e., C 〉 0, C = 0, and C 〈0. Following the C's values the spectrum of quantum states is discrete (C 〉 0) or continuous (C ≤ 0). 展开更多
关键词 time-dependent systems invariant theory Aharonov-Bohm effect Pauli equation
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Two Dimensional Cahn-Hilliard Equation with Concentration Dependent Mobility and Gradient Dependent Potential 被引量:1
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作者 HUANG RUI YIN JING-XUE WANG LIANG-WEI 《Communications in Mathematical Research》 CSCD 2011年第2期156-168,共13页
In this paper we consider the initial boundary value problem of Cahn-Hilliard equation with concentration dependent mobility and gradient dependent potential. By the L^P type estimates and the theory of Morrey spaces,... In this paper we consider the initial boundary value problem of Cahn-Hilliard equation with concentration dependent mobility and gradient dependent potential. By the L^P type estimates and the theory of Morrey spaces,we prove the Holder continuity of the solutions.Then we obtain the existence of global classical solutions.The present work can be viewed as an extension to the previous work on the Cahn-Hilliard equation with concentration dependent mobility and potential. 展开更多
关键词 Cahn-Hilliard equation concentration dependent mobility gradient de- pendent potential
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A streamline diffusion nonconforming finite element method for the time-dependent linearized Navier-Stokes equations 被引量:1
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作者 陈豫眉 谢小平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第7期861-874,共14页
A nonconforming finite element method of finite difference streamline diffusion type is proposed to solve the time-dependent linearized Navier-Stokes equations. The backward Euler scheme is used for time discretizatio... A nonconforming finite element method of finite difference streamline diffusion type is proposed to solve the time-dependent linearized Navier-Stokes equations. The backward Euler scheme is used for time discretization. Crouzeix-Raviart nonconforming finite element approximation, namely, nonconforming (P1)2 - P0 element, is used for the velocity and pressure fields with the streamline diffusion technique to cope with usual instabilities caused by the convection and time terms. Stability and error estimates are derived with suitable norms. 展开更多
关键词 streamline diffusion method finite difference method nonconforming finite element method time-dependent linearized Navier-Stokes equations error estimate
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Momentum Eigensolutions of Feinberg-Horodecki Equation with Time-Dependent Screened Kratzer-Hellmann Potential 被引量:1
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作者 Mahmoud Farout Sameer M. Ikhdair 《Journal of Applied Mathematics and Physics》 2020年第7期1207-1221,共15页
We obtain an approximate value of the quantized momentum eigenvalues, <em>P<sub>n</sub></em>, together with the space-like coherent eigenvectors for the space-like counterpart of the Schr<sp... We obtain an approximate value of the quantized momentum eigenvalues, <em>P<sub>n</sub></em>, together with the space-like coherent eigenvectors for the space-like counterpart of the Schr<span style="white-space:nowrap;">&#246;</span>dinger equation, the Feinberg-Horodecki equation, with a screened Kratzer-Hellmann potential which is constructed by the temporal counterpart of the spatial form of this potential. In addition, we got exact eigenvalues of the momentum and the eigenstates by solving Feinberg-Horodecki equation with Kratzer potential. The present work is illustrated with three special cases of the screened Kratzer-Hellman potential: the time-dependent screened Kratzer potential, time-dependent Hellmann potential and, the time-dependent screened Coulomb potential. 展开更多
关键词 Coherent States Feinberg-Horodecki equation time-dependent Screened Kratzer-Hellmann Potential time-dependent Kratzer Potential time-dependent Yukawa Potential time-dependent Hellmann Potential time-dependent Coulomb Potential
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Solving the time-dependent Schrödinger equation by combining smooth exterior complex scaling and Arnoldi propagator 被引量:1
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作者 Shun Wang Wei-Chao Jiang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期227-234,共8页
Abstract We develop a highly efficient scheme for numerically solving the three-dimensional time-dependent Schrödinger equation of the single-active-electron atom in the field of laser pulses by combining smooth ... Abstract We develop a highly efficient scheme for numerically solving the three-dimensional time-dependent Schrödinger equation of the single-active-electron atom in the field of laser pulses by combining smooth exterior complex scaling(SECS)absorbing method and Arnoldi propagation method.Such combination has not been reported in the literature.The proposed scheme is particularly useful in the applications involving long-time wave propagation.The SECS is a wonderful absorber,but its application results in a non-Hermitian Hamiltonian,invalidating propagators utilizing the Hermitian symmetry of the Hamiltonian.We demonstrate that the routine Arnoldi propagator can be modified to treat the non-Hermitian Hamiltonian.The efficiency of the proposed scheme is checked by tracking the time-dependent electron wave packet in the case of both weak extreme ultraviolet(XUV)and strong infrared(IR)laser pulses.Both perfect absorption and stable propagation are observed. 展开更多
关键词 time-dependent Schrödinger equation(TDSE) smooth exterior complex scaling(SECS)absorb-ing method Arnoldi propagator
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Lie symmetries and conserved quantities for a two-dimentional nonlinear diffusion equation of concentration
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作者 赵丽 傅景礼 陈本永 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期30-34,共5页
The Lie symmetries and conserved quantities of a two-dimensional nonlinear diffusion equation ot concentration are considered. Based on the invariance of the two-dimensional nonlinear diffusion equation of concentrati... The Lie symmetries and conserved quantities of a two-dimensional nonlinear diffusion equation ot concentration are considered. Based on the invariance of the two-dimensional nonlinear diffusion equation of concentration under the infinitesimal transformation with respect to the generalized coordinates and time, the determining equations of Lie symmetries are presented. The Lie groups of transformation and infinitesimal generators of this equation are obtained. The conserved quantities associated with the nonlinear diffusion equation of concentration are derived by integrating the characteristic equations. Also, the solutions of the two-dimensional nonlinear diffusion equation of concentration can be obtained. 展开更多
关键词 Lie symmetry conserved quantity NONLINEAR diffusion equation of concentration
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KINETIC EQUATIONS WITH VARIATION OF LIQUID REACTANT CONCENTRATION
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作者 YIN Qunsheng ZHAO Tiancong ZHONG Tingke LIN Ruoya Central South University of Technology,Changsha,China YIN Qunsheng Lecturer Dept.of Metallurgy,Central South University of Technology Changsha 410083,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1990年第10期258-264,共7页
For two common types of liquid-solid heterogeneous reactions,the kinetic equations have been established which involved both the variation of liquid reactant concentration and the va- riation of solid reactant geornet... For two common types of liquid-solid heterogeneous reactions,the kinetic equations have been established which involved both the variation of liquid reactant concentration and the va- riation of solid reactant geornetry with the reaction time.The experimental results show that the kinetic equations are more accurate and reasonable than those appeared in previous litera- tures.Moreover,they are also suitable for gas-solid heterogeneous reactions in principle. 展开更多
关键词 kinetic equation heterogeneous reaction reactant concentration
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Variable Coefficient KdV Equation for Amplitude of Nonlinear Solitary Rossby Waves in a Sort of Time-Dependent Zonal Flow
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作者 DA Chao-jiu SUN Shu-peng +1 位作者 SONG Jian YANG Lian-gui 《高原气象》 CSCD 北大核心 2011年第2期349-354,共6页
On the basis of the quasi-geostrophic vorticity equation,theoretical research has been down upon the evolution of the amplitude of solitary Rossby waves employing the perturbation method,and come to the conclusion tha... On the basis of the quasi-geostrophic vorticity equation,theoretical research has been down upon the evolution of the amplitude of solitary Rossby waves employing the perturbation method,and come to the conclusion that the evolution of the amplitude satisfies the variable coefficient Korteweg-de Vries(KdV) equation. 展开更多
关键词 NONLINEAR ROSSBY Waves Variable coefficient KDV equation time-dependent zonal flow Perturbation method
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Form-Preserving Transformations of Time-Dependent Schrodinger Equation withTime- and Position-Dependent Mass
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作者 AxelSchulze-Halberg 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期657-665,共9页
We study space-time transformations of the time-dependent Schrodingerequation (TDSE) with time- and position-dependent (effective) mass. We obtain the most generalspace-time transformation that maps such a TDSE onto a... We study space-time transformations of the time-dependent Schrodingerequation (TDSE) with time- and position-dependent (effective) mass. We obtain the most generalspace-time transformation that maps such a TDSE onto another one of its kind. The transformedpotential is given in explicit form. 展开更多
关键词 time-dependent schrodinger equation space-time transformation time- andposition-dependent mass exact solutions
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Wave Functions for Time-Dependent Dirac Equation under GUP
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作者 Meng-Yao Zhang Chao-Yun Long Zheng-Wen Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第4期383-386,共4页
In this work, the time-dependent Dirac equation is investigated under generalized uncertainty principle(GUP) framework. It is possible to construct the exact solutions of Dirac equation when the time-dependent potenti... In this work, the time-dependent Dirac equation is investigated under generalized uncertainty principle(GUP) framework. It is possible to construct the exact solutions of Dirac equation when the time-dependent potentials satisfied the proper conditions. In(1+1) dimensions, the analytical wave functions of the Dirac equation under GUP have been obtained for the two kinds time-dependent potentials. 展开更多
关键词 time-dependent Dirac equation generalized uncertainty principle exact solutions
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Efficient solver for time-dependent Schrodinger equation with interaction between atoms and strong laser field
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作者 Sheng-Peng Zhou Ai-Hua Liu +2 位作者 Fang Liu Chun-Cheng Wang Da-Jun Ding 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第8期66-72,共7页
We present a parallel numerical method of simulating the interaction of atoms with a strong laser field by solving the time-depending Schr?dinger equation(TDSE) in spherical coordinates. This method is realized by com... We present a parallel numerical method of simulating the interaction of atoms with a strong laser field by solving the time-depending Schr?dinger equation(TDSE) in spherical coordinates. This method is realized by combining constructing block diagonal matrices through using the real space product formula(RSPF) with splitting out diagonal sub-matrices for short iterative Lanczos(SIL) propagator. The numerical implementation of the solver guarantees efficient parallel computing for the simulation of real physical problems such as high harmonic generation(HHG) in these interaction systems. 展开更多
关键词 time-dependent Schrodinger equation Strong laser fields Parallel numerical solver
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Time-dependent Ginzburg-Landau equation for lattice hydrodynamic model describing pedestrian flow
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作者 葛红霞 程荣军 卢兆明 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期104-108,共5页
A thermodynamic theory is formulated to describe the phase transition and critical phenomena in pedestrian flow. Based on the extended lattice hydrodynamic pedestrian model taking the interaction of the next-nearest-n... A thermodynamic theory is formulated to describe the phase transition and critical phenomena in pedestrian flow. Based on the extended lattice hydrodynamic pedestrian model taking the interaction of the next-nearest-neighbor persons into account, the time-dependent Ginzburg-Landau (TDGL) equation is derived to describe the pedestrian flow near the critical point through the nonlinear analysis method. The corresponding two solutions, the uniform and the kink solutions, are given. The coexisting curve, spinodal line, and critical point are obtained by the first and second derivatives of the thermodynamic potential. 展开更多
关键词 pedestrian flow lattice hydrodynamic model time-dependent Ginzburg–Landau equation
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