An optimization model for monthly timber flow planning

The problem we consider is monthly timber flow planning from the perspective of Russian forest companies. The main decisions deal with which areas to harvest during an annual period so that the wood-processing facilities receive the required amount of assortments. Each area has a different size and composition of assortments, and the choice of harvesting areas affects the production level of different assortments. We need to decide how to allocate sites among existing logging crews, while taking into account that each crew has different characteristics. We need create optimal schedule for each crew. Also storage volumes should be minimized. In addition, we need to solve timber flow problem, considering transportation restrictions, weather conditions, accessibility and maximum turnover of elements of road network. In this paper, we develop a mixed integer programming model for the problem. Model created in modeling system AIMMS and solved directly by using commercial solver CPLEX v12.6.3. Computational results from a major Leningrad Region logging company are presented.