  The area-perimeter allometric scaling is a basic and important approach for
researching fractal cities and has been studied for a long time. However, the
boundary dimension of a city is always numerically overestimated by the
traditional formula. An adjusting formula has been derived to revise the
overestimated boundary dimension and estimate the form dimension, but the
association between the global and local fractal parameters is not clear. This
paper is devoted to describing the urban evolution by using the improved
fractal parameters based on the area-perimeter measure relation. A system of 68
cities and towns in Yangtze River Delta, China, is taken as an example to make
a case study. A discovery is that the average values of the local fractal
parameters are approximately equal to the corresponding global fractal
parameters of cities. This suggests that the local parameters are the
decomposition of the global parameters. The novelty of this empirical study is
as follows: first, the form dimension and boundary dimension are integrated to
characterize the urban structure and texture; second, the global and local
parameters are combined to characterize an urban system and individual cities.
By illustrating how to carry out the area-perimeter scaling analysis in the
case of remote sensing images with low resolution, this work suggests a
possible new approach to researching fractal systems of cities.
