Study of life cycle design focusing on resource balance throughout product life cycles

Life cycle design is a promising approach for introducing efficient resource circulation. In such design, there are difficulties in balancing demand and supply for resources throughout product life cycles. For the resource balance, it is important to design a product life cycle focusing on individual products and their parts, since they change their states diversely and flow along different circulation paths through their life cycles. This paper proposes a modelling method for the individual products and parts in addition to its design information. The design information is the nominal information of the product specified by designers. To achieve this, this paper defines three models; hierarchical structure model, life cycle flow model, and entity information model. Hierarchical structure model represents design information of a product. Life cycle flow model represents a network of processes included in product life cycles. Entity information model represents information of individual products and parts. The information indicates when each product and part flows along which circulation paths in which state. With this information, this method represents resource balance throughout product life cycles. Moreover, this study employs life cycle simulation technique to derive the entity information model from the hierarchical structure model and life cycle flow model. We demonstrate the proposed modelling method via its application to a smart phone in a case study.