Modelling the running states of high-speed trains using triangular fuzzy number workflow nets

Abstract

In this paper, we propose the use of workflow nets to study the issues associated with deriving the running states of trains. Triangular fuzzy numbers are introduced to express the train’s activity times and to aid in the modelling using workflow nets of the running processes of high-speed trains. A workflow net links all the activities of a train’s running processes into a sequence called a train running workflow net for high-speed trains. The main job of a triangular fuzzy number workflow net is triangular fuzzy number operation. The principles of this operation are discussed in this paper. The connotations of the two modes of operation of train running workflow nets—sequential mode and alternative mode—are also analysed. In addition, methods for calculating the time duration during which a triangular fuzzy number workflow net operates, both in sequential mode and alternative mode, for high-speed trains are proposed and proved. Train activity times and running status can be forecast by executing the proposed triangular fuzzy number workflow nets.