A New Model of Urban Population Density Indicating Latent Fractal Structure

摘要

Fractal structure of a system suggests the optimal way in which partsarranged or put together to form a whole. The ideas from fractals have apotential application to the researches on urban sustainable development. Tocharacterize fractal cities, we need the measure of fractional dimension.However, if the fractal organization is concealed in the complex spatialdistributions of geographical phenomena, the common methods of evaluatingfractal parameter will be disabled. In this article, a new model is proposed todescribe urban density and estimate fractal dimension of urban form. If urbandensity takes on quasi-fractal pattern or the self-similar pattern is hidden inthe negative exponential distribution, the generalized gamma function may beemployed to model the urban landscape and estimate its latent fractaldimension. As a case study, the method is applied to the city of Hangzhou,China. The results show that urban form evolves from simple to complexstructure with time.