因为许多离散生产过程都可以用离散事件系统描述，所以离散事件动态系统有很强的实用背景，例如柔性制造系统，因此，受到国内外的广泛注意和重视，进行深入研究，已获得一些很重要的理论结果．本文试图用图论的观点和方法，对离散事件动态系统的某些重要结果予以注释和新的证明，并探讨图论在该领域研究中的进一步应用．

Since many discrete production processes can be described by using discretevent systems, discrete event dynamic systems have a very strong background of applications,for instance, application to flexible manufacturing systems. So great attention has been paid to discrete-event dynamic systems both domestically and internationally, deep studies were made,and a number of meaningful results were obtained. In this paper we try to give explanatory notes and new proofs for some important results by using the graph theory viewpoint and methods,and attempt to go further into the application of graph theory to the study of discrete-event dynamic systems.