Phi-Functions for 2D Objects Formed by Line Segments and Circular Arcs

• Main Authors: N. Chernov, Yu. Stoyan, T. Romanova, A. Pankratov
• Format: Article
• Language: English
• Published: Hindawi Limited 2012-01-01
• Series: Advances in Operations Research
• Online Access: http://dx.doi.org/10.1155/2012/346358

We study the cutting and packing (C&P) problems in two dimensions by using phi-functions. Our phi-functions describe the layout of given objects; they allow us to construct a mathematical model in which C&P problems become constrained optimization problems. Here we define (for the first time) a complete class of basic phi-functions which allow us to derive phi-functions for all 2D objects that are formed by linear segments and circular arcs. Our phi-functions support translations and rotations of objects. In order to deal with restrictions on minimal or maximal distances between objects, we also propose adjusted phi-functions. Our phi-functions are expressed by simple linear and quadratic formulas without radicals. The use of radical-free phi-functions allows us to increase efficiency of optimization algorithms. We include several model examples.