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# Solving QBF with Heuristic Small W orld

In this paper, we use gaifman graph to describe the topological structure of the Quantified Boolean Formulae
(QBF), we mainly study the formula family with the Small World (SW) network topology. We analyze the t raditional Davis,
Putnam, Logemann and Loveland (DPLL) solving algori thm for QBF, then we improve the DPLL algorithm and propose the
solving algorithm framework based on Small World Op timization Search (SWOS) algorithm, we apply this SWOS algorithm to
determine the order of the DPLL branch variable. Ou r result proves that SWOS algorithm has a certain degree of effectiveness
to improve the solving efficiency. It is valuable a s an incomplete solution algorithm for search1based solver.

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[29] Yin M., Zhou J., Sun J., and Gu W., Heuristic Survey Propagation Algorithm for Solving QBF Problem, Ruanjian Xuebao/Journal of Software , vol. 22, no. 7, pp. 153821550, 2011. Tao Li is a scientific researcher and project manager in Modern Education and Technology Center, South China Agricultural University and holds an IEEE membership. He completed his PhD degree in School of Computer Science and Engineering, South China University of Technology. His research interests include intelligent computin g and data mining. Nanfeng Xiao is currently a Professor and PhD tutor of computer science in School of Computer Science and Engineering, South China University of Technology. His research interests are in the areas of intelligent computing, intelligent robots and data mining.