PROJECT GIGALOPOLIS

 

OVERVIEW

 

Developed by Dr. Keith C. Clarke, research continues at the University of California, Santa Barbara, Department of Geography. This work began through sponsorship from the United States Geological Survey's Urban Dynamics program, and continues under the NSF funded Urban Research Initiative. A related UCSB website focusing on the NSF work is located on the UC-IME project page.

The Urban Growth Model (UGM) is a C program running under UNIX that uses the standard gnu C compiler (gcc) and may be executed in parallel. It can be formatted for any other standard C compiler. Some minor changes in the code might be necessary for execution in new environments. In order to implement the model a good understanding of C programming is expected.

The land cover deltatron model (LCD) is included within the code and will be called and driven by the UGM. The LCD is tightly coupled with the urban code, but the UGM can run independently of it. Together, these coupled models are referred to as SLEUTH. The name SLEUTH was derived from the simple image input requirements of the models: Slope, Land cover, Exclusion, Urbanization, Transportation, andHillshade. For a thorough explanation and history of this work, the publications pages should be reviewed.

Tom Boutell's C language gd graphic libraries are also used and are included with the downloaded code. These libraries manipulate GIF images, and are no longer supported by the GD site which has converted to more open image formats such as PNG.

For the execution of the model, it is assumed in this documentation that all program and input files are located as they are in the downloaded directory structure. The input files must be in the proper format, and a naming convention must be followed in order for the model to read data in correctly. In order to intelligently calibrate the model a thorough understanding of the growth rules, scenario file and statistical output files is necessary and should be reviewed carefully.

We have created a hypothetical data set, Demo_city, to help illustrate the implementation of the model. The downloaded model's values will be set to accept these data and execute a test run. To gain an understanding of how the model works, and verify its function, we recommend first using Demo_city to run an entire calibration. These output can then be compared to ours for the same data. Once successful calibration and output has been achieved with Demo_city, parameter settings can be changed to accept any properly formatted data set.

 

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