“…In this research, the OCC model proposed by [36] is adopted to assess the inherent complexity of assembly systems. OCC is a widely used information-theoretic complexity quantification model for mixed-model manual assembly systems [2], [19], [20], [28], [29], [31], [36]- [42] relating complexity to the varietyinduced operational uncertainty associated with assembly choices that are made by assembly operators. In such a sense, OCC is only able to measure variety-induced complexity in manual assembly systems.…”