摘要:

Moments and probability distribution of time series generated by a stochastic differential equation with two random coefficients are investigated by discrete time-dependent model of the noise and a computer simulation. Influence of initial condition, amplitude of fluctuation, and time correlation of frequency noise upon time dependence of the moment is pointed out theoretically and actual calculation is done by a computer simulation. It is found from the simulation, for example, that time correlated frequency model introduced in this paper suppresses divergence of second moment. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291576

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291577

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291578

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

The relaxation process of the vicinal surface is analyzed by the Ginzburg-Landau-Langevin (GLL) equation and the Monte-Carlo simulation. By the GLL equation, the three quantities characterizing the surface fluctuation are calculated. The three quantities are expressed in terms of the two universal scaling functions and the five system specific quantities. Two universal relations among the five quantities are also derived. These were verified by the Monte-Carlo simulation. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291579

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291580

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

We make statistical mechanical calculations of surface step quantities by imaginary path-weight method and product wave-function renormalization group method. We apply our results to Si(001) and Si(111) surfaces, and show that our results are in good agreement with recent experiments. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291581

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

An efficient scheme is introduced to calculate the Green function on the basis of polynomials expansion. The scheme has the following advantages: (i) it is possible to calculate both the diagonal and off-diagonal elements of the Green function, (ii) applicable to the system with discrete spectrum, (iii) integrated density of states can also be obtained by the same algorithm. Applications are made to model systems with discrete spectrum. Results of a preliminaryab initiocalculations for a bulk system are also demonstrated. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291582

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

The optimized expansion is applied to the quantum mechanical evolution amplitude, providing approximations to the density matrix and to the particle density. For the anharmonic oscillator and for the electron in the hydrogen atom the first order approximations to particle density agree well with the exact results. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291583

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

Applying the C*-algebraic method to a 1-d conductor placed between two reservoirs, the approach to nonequilibrium stationary states with nonvanishing currents is shown exactly. Further characterization of the stationary state obtained from the forward time evolution is given and is compared with other approaches. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291584

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

An integration of a deterministic Langevin type equation, driven by a chaotic force, is discussed:x˙(t)=x(t)−x(t)2+x(t)fc(t).The chaotic forcefc(t)defined byfc(t)=(K/&tgr;)y⁁k(y0)fork&tgr;<t⩽(k+1)&tgr;,(k=0,1,2,&ellip;),whereykis a chaotic sequence of a mapF(yk):yk+1=F(yk).The deviationy⁁kisyk−⟨y0⟩,where ⟨&ellip;⟩ means the average over the invariant density&rgr;(y0)ofF(y).In the small &tgr; limit the result is compared with the result in the stochastic differential equation. The similar results as in the stochastic case are obtained due to the factor1/&tgr;of the chaotic forcefc(t).©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1291585

出版商:AIP    

年代:1900

数据来源: AIP