We use the distance decay function to break down count data published for one fixed set of irregular areal units into a fine grid which can then be reaggregated to other sets of areas and thus used in conjunction with information .

This study,based on the distance decay of information transmission theory and information flow diffusion theory,designs for the study system of distance decay effect in network information flows in China.

As a classic quantitative model the distance decay model has been widely used in various branches of research.

Although there are case studies on such issues as mathematical modeling of distance decay of tourists from a tourist site, its market potential and actual market structure, many questions remain.

The attenuation function or magnetic induction function is used as field function,which reflects clustering effect around the corridor.

The Exponent Function Model(EFM) is used to approximately handle the attenuation function of the random time-dependent structure resistance,and evaluate separately the risk probabilities in the course of resistance attenuation during the design datum duration T.

According to the state equation of dynamic system,the paper puts forward the calculating method of attenuation function of vibration mode by making use of system matrix.