Thomas C. Maness

Multiple Period Combined Optimization Approach to Forest Production Planning

Recent efforts on the development of production planning systems for sawmills have focused on combined optimization type solutions in a steady-state market environment. This paper describes a linear programming-based multiple period production planning system which responds to expected changes in product value or market demand by changing policies with regard to sawing patterns and log consumption. Log and lumber inventories tie production periods together. The model was tested on a large log mill in British Columbia producing export products. It is shown that the model responds to market changes using sawing pattern selection and altered log consumption.

A relational database approach to a linear programming-based decision support system for production planning in secondary wood product manufacturing

Secondary manufacturers in the forest products industry face a complex production planning process. Linear programming (LP)-based applications have addressed this production planning issue. However, most models have been developed for a specific plant configuration and cannot readily be applied to others. A relational database approach was used to create an integrated linear programming-based decision support system that can be used to analyze production planning issues in a wide variety of secondary wood product manufacturers. The flexibility of the resultant system indicated the potential to analyze production strategies in the highly dynamic environment characteristic of secondary manufacturers.

Applying Real-Time Statistical Process Control to Manufacturing Processes Exhibiting Between and Within Part Size Variability in the Wood Products Industry

In this paper, we develop a control charting procedure to monitor average part size, as well as between and within part size variation for sawn lumber in an automated lumbermill. We present a review of the sawing process followed by a discussion of sampling methods for a real-time noncontact laser measuring device. A statistical model based on the components of variation analysis of variance model is proposed both for the analysis of the data and the construction of control charts that can be used to monitor the process. The details of the resulting statistical process control system are developed and an example from the lumber industry is provided and compared to other possible approaches. The resulting techniques may have applicability in many other industries where within and between variation in processes occurs.