Application of Wavelet Fractal Dimension Estimation in Dividing Flood Stages for Three Gorges Reservoir
Abstract Limit water level control improves water resources utilization efficiency without reducing flood control standard, while the premise is to divide the discharge series into a number of different flood stages. Db4 is selected as wavelet base, based on Mallat algorithm, put forward the model of wavelet dimension estimation method and calculated the fractal dimension of floods at the Yichang station, got the flood periods of Three Gorges reservoir. The results indicate that the method of wavelet dimension estimation can obtain the same result as traditional methods, and it has the merit of simplicity and stability. As a feasible and effective tool, the wavelet dimension estimation method is recommended in the applications of dividing flood periods.
A brief introduction to the fractal theory and methodology
Recently,rapid progress has been achieved in the field of coagulation.One of the frontier and dey topics is the formation,structure and property of aggregated flocs.A critical review on the potential application of fractal theory in various aspects of coagulation would be needed.This paper introduces first the basic fractal theory and methodology as well.
On the sediment volume of colloidal aggregates 1. A fractal approach to the problem
A new approach based on the fractal geometry of random aggregates is used to describe the concentration of the sediment formed by the settling of colloidal aggregates. It is predicted that the sediment concentration depends not only on the adhesion forces, but also on the size of the settling particles. Experimental results performed on iron(III) hydroxide sols qualitatively support our ideas.