Hierarchical partition of nonstructured concurrent systems

In this paper, the concepts of structured and nonstructured concurrency are introduced to classify concurrent systems, and a hierarchical partition method is used to handle the complexity of nonstructured concurrent systems. A concurrent system with structured and nonstructured concurrency is modeled by a precedence graph. The language of the precedence graph is defined, and a representation method of the language is developed. By decomposing the language hierarchically, hierarchical partitions of the concurrent system can be obtained. From the partitions, a concurrent system can be reduced hierarchically.