A shape-based buffering method

Distance constraint is a major concern in many spatial analyses. Buffering is one of the proximity techniques in GIS most commonly used to address this constraint. I introduce shape-based point buffering, an anisotropic and variable-distance buffer generation method conformal to the original polygons. In contrast with isotropic fixed-distance buffering, shape-based buffering is defined using a relative distance (percentage) instead of a real unit (for example, meters), and it allows all buffered boundaries to be formed at the same time. The construction and implementation of the buffering method are described below. Three emergency-response scenarios are designed to demonstrate potential applications of this buffering method, including a shape-based fixedpercentage buffer calculation and space distribution, a shape-based variable-percentage buffer region, and a reverse calculation of the task schedule from a probability surface constructed from shape-based buffers. Limitations of the method are discussed. The method has potential applications in emergency preparedness and planning to better address fairness issues when a geographic area must be zoned arbitrarily. doi:10.1068/b33046