The Combined Optimization of Log Bucking and Sawing Strategies
Keywords:Sawmill planning, linear programming, decomposition, process control
AbstractDetermination of optimal bucking and sawing policies is linked in a common model. The core of this model is a linear program (LP) that selects stem bucking and log sawing policies to maximize profits given an input distribution of raw material. Product output is controlled by price-volume relationships that simulate product demand curves. The model uses a three stage solution process performed iteratively until identical solution bases are obtained. A variation of the Dantzig-Wolfe decomposition principle is used, linking the three models through the use of the Lagrange multipliers from the LP. The procedure is demonstrated for a sample sawmill. The revenue gain from using the policies suggested by the integrated model over those found by the bucking and sawing programs working separately was found to be 26%-36%.
Briggs, D. G. 1980. A dynamic programming approach to optimizing stem conversion. Ph.D. dissertation, University of Washington, Seattle, WA.nDantzig, G. B., and P. Wolfe. 1960. Decomposition principle for linear programs. Operations Research 8:101-111.nEng, G., H. G. Dallenbach, and A. G. D. Whyte. 1986. Bucking tree-length stems optimally. Canadian J. Forest Res. 16:1030-1035.nFaaland, B., and D. G. Briggs. 1984. Log bucking and lumber manufacturing using dynamic programming. Management Sci. 30(2):245-257.nGluck, P., and W. Koch. 1973. Die optimale rohholzausformung. Centralblatt fur des Gesampte Forstwesen 90(4):1193-1228.nJackson, N. D., and G. W. Smith. 1961. Linear programming in lumber production. Forest Prod. J. 11:272-274.nManess, T. C. 1989. A technique for the combined optimization of log sawing and bucking strategies. Ph.D. dissertation, University of Washington, Seattle, WA.nMcPhalen, J. C. 1978. A method of evaluating bucking and sawing strategies for sawlogs. M.S. thesis, University of British Columbia, Vancouver, B.C., Canada.nMendoza, G. A. 1980. Integrating stem conversion and log allocation models for wood utilization planning. Ph.D. dissertation, University of Washington, Seattle, WA.nPearse, P. H., and G. Sydneysmith. 1966. Method for allocating logs among several utilization processes. Forest Prod. J. 16(9):87-98.nPnevmaticos, S. M., and S. H. Mann. 1972. Dynamic programming in tree bucking. Forest Prod. J. 22(2):26-30.nRow, C., C. A. Fasick, and S. Guttenberg. 1965. Improving sawmill profits through operations research. USDA Forest Service Research Paper SO-20, Southern Forest Experiment Station. 26 pp.nSampson, G. R., and C. A. Fasick. 1970. Operations research application in lumber production. Forest Prod. J. 20(5):12-16.n
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