Optimization and Systems Theory Seminar
April 25, 1997, 11.00-12.00

Mikael Rönnqvist
Division of Optimization
Department of Mathematics
Linköping University

Production systems in forestry using operations research techniques

As the forestry industry has become more competitive, the use of Operations Research (OR) technologies has increased. In this seminar I will discuss the development of two production systems for a major forestry company in New Zealand where mathematical modeling and optimization have a significant role. The first concerns the despatching of logging trucks, i.e., to organise "good" trips for trucks in a continuous process. These trucks transport logs from harvesting locations to customers such as saw-mills and pulp-mills.
There are a large number of "constraints" which must be met. At the same time there are many conflicting objectives which arise between different parties, such as forestry owners, customers and truck drivers. A difficulty is that supply of and demand for logs is continuously changing during the day so there is a need to have accurate information available at all times.
The second system is related to the cutting of full trees to products, i.e. logs of different lengths and quality, at harvesting locations. This cross-cutting is currently a manual decision process. However, due to an increasing complexity of quality requirements and an increasing number of products, there are also an increasing number of logs which are out of specification. It is therefore a need to develop systems that are capable to automate the process while at the same time take into account quality restrictions and collect necessary data in a production environment.

Calendar of seminars
Last update: March 26, 1997 by Anders Forsgren, andersf@math.kth.se.