We study an extension of the precedence constrained knapsack problem where the knapsack can be filled in multiple periods. This problem is known in the mining industry as the open-pit mine production scheduling problem. We present a new algorithm for solving the LP relaxation of this problem and an LP-based heuristic to obtain feasible solutions. Computational experiments show that we can solve real mining instances with millions of items in minutes, obtaining solutions within 6% of optimality.
- Integer Programming
- Open-pit Mining
- Precedence Constrained Knapsack Problem