Abstract：The recent progresses in non-equilibrium statistical mechanics are summarized and an attempt is made to build a new descriptive method based on a new variational principle. By employing Maximum Flux Principle, as modified Hamilton principle for open systems, a new statistical ensemble is developed and a new potential function is defined. Then the Langevin equation and the renormalization equation are obtained, through which the fractal structure is ultimately derived. A new framework of statistical mechanics is therefore outlined. With an example of quantitative analysis of urban system, it shows advantages and potentialities in dealing with universal open complex systems.
2007, Vol. 25 
