Zheng, X.; Sun, X.; Li, D.; Xu, Y. - In: Journal of Global Optimization 54 (2012) 2, pp. 325-339
We investigate in this paper the duality gap between quadratic knapsack problem and its Lagrangian dual or semidefinite programming relaxation. We characterize the duality gap by a distance measure from set {0, 1}<Superscript> n </Superscript> to certain polyhedral set and demonstrate that the duality gap can be reduced...</superscript>