An Application of a Heuristic Network Algorithm to Cable Logging Layout Design
Authors
Woodam Chung
University of Montana
John Sessions
Oregon State University
Hans R. Heinimann
Abstract
This paper describes a method for optimizing cable logging layouts using a heuristic network algorithm. A timber harvest unit layout is formulated as a network problem. Each grid cell containing timber volume to be harvested is identified as an individual entry node of the network. Mill locations or proposed timber exit locations are identified as destinations. Each origin will then be connected to one of the destinations through alternative links representing alternative cable corridors, harvesting equipment, landing locations, and truck road segments. A heuristic algorithm for network programming is used to solve the cost minimization network problem. A computerized model has been developed to implement the method. Logging feasibility and cost analysis modules are included in the model in order to evaluate the logging feasibility of alternative cable corridors and estimate yarding and transportation costs. The model was successfully applied to a harvest planning area to generate harvesting plans. This case study indicates that the planning method is best used for pre-planning since modeling assumptions with respect to tail spar availability and unconstrained road alignments may require modification of the plan before implementation.
