Abstract
Under the great development of application about supply chain management and produce strategy, Service-Added Manufacturing is more impotant.Thersfore, Brand owner in technology industry may outsource their after-sales service to Service Company in order to lower total supply chain cost. In this way, they can focus on their own core business and on the other hand they can gain customer loyalty though that. Service Company covers various levels of the service process chain and provides total solutions to Brand owner. The service includes full repair capability, reverse logistics, warehouse management, global service center, product life cycle plan and comprehensive IT solutions. During the service period, when product is phased-out, but Service Company still needs to supply enough demands to customers till the service ends. At this moment, Service Company must do Last Time Buy (LTB) for the future demands based on past usage and forecast. However, shortage or excess problems may occur due to high uncertainty of future demands. This research builds up the LTB decision structure based on uncertainty and risk structure. It uses decision tree and sequential tree to help decision makers do systematic LTB decision with LTB decision model. Finally, it takes the real case of W Company for studies and the result shows practical viability of LTB decision structure approach for troubleshooting.