Simulation Model Using Meta Heuristic Algorithms for Achieving Optimal Arrangement of Storage Bins in a Sawmill Yard

Bin planning (arrangements) is a key factor in the timber industry. Improper planning of the storage bins may lead to inefficient transportation of resources, which threaten the overall efficiency and thereby limit the profit margins of sawmills. To address this challenge, a simulation model has been developed. However, as numerous alternatives are available for arranging bins, simulating all possibilities will take an enormous amount of time and it is computationally infeasible. A discrete-event simulation model incorporating meta-heuristic algorithms has therefore been investigated in this study. Preliminary investigations indicate that the results achieved by GA based simulation model are promising and better than the other meta-heuristic algorithm. Further, a sensitivity analysis has been done on the GA based optimal arrangement which contributes to gaining insights and knowledge about the real system that ultimately leads to improved and enhanced efficiency in sawmill yards. It is expected that the results achieved in the work will support timber industries in making optimal decisions with respect to arrangement of storage bins in a sawmill yard.

Simulation and Optimization Techniques for Sawmill Yard Operations——A Literature Review

Increasing costs and competitive business strategies are pushing sawmill enterprises to make an effort for optimization of their process management. Organizational decisions mainly concentrate on performance and reduction of operational costs in order to maintain profit margins. Although many efforts have been made, effective utilization of resources, optimal planning and maximum productivity in sawmill are still challenging to sawmill industries. Many researchers proposed the simulation models in combination with optimization techniques to address problems of integrated logistics optimization. The combination of simulation and optimization technique identifies the optimal strategy by simulating all complex behaviours of the system under consideration including objectives and constraints. During the past decade, an enormous number of studies were conducted to simulate operational inefficiencies in order to find optimal solutions. This paper gives a review on recent developments and challenges associated with simulation and optimization techniques. It was believed that the review would provide a perfect ground to the authors in pursuing further work in optimizing sawmill yard operations.

Soda pulping of umbrella palm grass (cyperus flabettiformic)

Chemical,morphological and anatomical characteristics of Cyperus flabettiformic were evaluated.It is characterized with lowα-cellulose(32.2%)and moderate lignin(24.0%)content.Fiber length of C.flabettiformic was shorter(0.94mm)but slender ratio was extremely high(166).Anatomically,this grass is constituted by homogeneous parenchyma cells and the vascular bundles(11.8%).Delignification of C.flabettiformic was carried out by conventional soda pulping under varying alkali charge,time and liquor to material ratio at the boiling temperature.Total pulp yield was 55.0%with kappa number 15.5 at the cooking conditions of 12%alkali charge,2 h of cooking and liquor to material ratio 10:1.Multivariate data analysis was used to evaluate the influence of alkali charge,cooking time and liquor ratio on pulp yield and kappa number.Alkali charge had a significant effect on pulp yield and kappa number.PLSR model showed better prediction efficiencies for pulp yield and PCR model performed better prediction for kappa number.Initial drainage resistance and papermaking properties of C.flabettiformic pulp were higher than other nonwood.