The aim of a decision support system (DSS) is to enhance the course of
decision-making by furnishing a decision episode and support during the
decision-making and enforcing procedure. Inspired by management information
systems, the DSS assists policy makers to reach a decision by man-machine
interaction through data, models and knowledge. Knowledge fusion is an
effective means of enhancing the efficiency of a DSS. Thus, this paper presents
a three-layer, six-step knowledge fusion pattern from the perspective of
interaction and the three procedures used to arrive at a decision. For
better understanding, an evaluation of the knowledge state with knowledge
objects in the fusion pattern is also presented. Furthermore, we briefly
examine a case study of a Fire Rescue DSS(FRDSS).