Leveraging tacit knowledge for shipyard facility layout selection using fuzzy set theory

Abstract

A shipyard's layout contributes significantly to manufacturing performance. The practitioners based on experience can provide feasible alternative layouts by considering qualitative factors. However, no study in the shipyard layout context has leveraged their valuable subjective knowledge.This study addresses the above research gap. It proposes a two-stage approach using the Fuzzy similarity index (FSI) and the Fuzzy goal programming model (FGPM). The first stage elicits alternative layouts and relationship (REL) charts from practitioners. REL's fuzzy proximity ratings are assigned by subjective assessment of shipbuilding process flow, inter-shop material flow, distance, cost per unit distance, sharing of material handling equipment. Thereafter, the FSI of each alternative layout with respect to the ideal layout is evaluated. However, implementing the alternative layout with the highest FSI may not be feasible due to practical constraints. Therefore, in the second stage, FGPM is formulated incorporating practical constraints related to site factors, harmful gases emission, environmental, and safety to yield an optimal selection of layout.