Abstract
The Petri nets have been used in system analysis for describing, understanding and analyzing the structure, procedures and states of a system. Lacking the logic gates, systems such as electronic circuit system, management information system(M.I.S.) are unabled to be completely described or analyzed by Petri nets. In this thesis, the Petri nets are extended to contain logic gates. That is, logic gates are represented by Petri nets. The extended Petri nets can be used as a tool for system analysis. Chapter 1 in this thesis briefly introduces Petri nets. Chapter 2 discusses the ways to represent kinds of logic gates by Petri nets. In chapter 3, the state equation of this logic-gates-containing Petri net is studied. Chapter 4 applied this extended Petri net to vacuum pumping system. Chapter 5 is the conclusion.