This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condit...This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condition is given and proven for the existence of a feasible priority-based controller based on the notions of liveness and transition invariants. Next, a cyclic behavior graph is constructed, which shows the reachable markings that guarantee the maximum liveness of the system within a given bound vector. Finally, an on-line control strategy is proposed to enforce boundedness and liveness to the given system by appending priority relations to transitions. The dynamic priority relation changes flexibly according to the current state of the system and enforces the system evolving in a bounded and live manner. In addition, numerical examples are studied to verify the validity of the proposed approach that remains the structure of the plant net and is efficient for on-line control.展开更多
In this paper, the Extended Strong Asymmetric Choice Nets Ⅱ (ESACN Ⅱ), a subclass of Asymmetric Choice Nets (ACN) including Extended Free Choice Nets (EFCN) and Strong Asymmetric Choke Nets Ⅱ (SACN Ⅱ, is presented...In this paper, the Extended Strong Asymmetric Choice Nets Ⅱ (ESACN Ⅱ), a subclass of Asymmetric Choice Nets (ACN) including Extended Free Choice Nets (EFCN) and Strong Asymmetric Choke Nets Ⅱ (SACN Ⅱ, is presented. A necessary and sufficient condition for liveness of ESACN Ⅱ is proposed. Moreover, a criterion is introduced, which is necessary and sufficient for judgement of liveness and boundedness of ESACN Ⅱ. Meanwhile a polynomial time algorithm is given to decide liveness and boundedness for ESACN Ⅱ.展开更多
针对嵌入式系统建模问题,提出了一种经由扩展Petri网共享子网得到组合网的解决方案。将面向对象技术与嵌入式系统的Petri网表示模型(PRES网)融合,得到一种面向对象的PRES网—OOPRES(object-oriented petri net based representation for...针对嵌入式系统建模问题,提出了一种经由扩展Petri网共享子网得到组合网的解决方案。将面向对象技术与嵌入式系统的Petri网表示模型(PRES网)融合,得到一种面向对象的PRES网—OOPRES(object-oriented petri net based representation for embedded system)网。提出了一种OOPRES网共享子网组合操作方法,并对其组合网系统的活性和有界性的保持问题进行了研究。以智能交通系统的建模分析为例验证了该组合方法的有效性。结果可为Petri网系统组合性质的考察提供有效途径,为大规模复杂嵌入式系统建模提供有利手段,具有宽广的应用前景。展开更多
针对柔性制造系统的设计和分析,提出了经由 Petri 网共享子网构成合成网的解决方案;研究了 Petri 网共享子网合成的动态性质保持问题,给出了合成网保持活性、有界性的一组充分条件;对一个柔性制造系统进行了设计和分析。本文的结果可为 ...针对柔性制造系统的设计和分析,提出了经由 Petri 网共享子网构成合成网的解决方案;研究了 Petri 网共享子网合成的动态性质保持问题,给出了合成网保持活性、有界性的一组充分条件;对一个柔性制造系统进行了设计和分析。本文的结果可为 Petri 网系统静态和动态性质的考察提供有效途径,为 Petri 网复杂大系统的分析提供重要手段,并特别适合于柔性制造系统的设计,具有一定的实用价值。展开更多
针对工厂用车间中的若干台机器加工某些部件等这一类业务处理问题,提出了用 Petri 网精细化操作解决问题的方案。定义了一种 PP-型子网,用这种子网分别对 Petri 网系统中的某些库所进行细化,得到更细致、更精确的Petri 网系统。研究了 P...针对工厂用车间中的若干台机器加工某些部件等这一类业务处理问题,提出了用 Petri 网精细化操作解决问题的方案。定义了一种 PP-型子网,用这种子网分别对 Petri 网系统中的某些库所进行细化,得到更细致、更精确的Petri 网系统。研究了 Petri 网精细化操作的动态性质保持问题,给出这种精细化操作保持活性、有界性、可回复性和公平性的充要条件;本文的结果可为 Petri 网系统静态和动态性质的考察提供有效途径,为 Petri 网复杂大系统的分析提供重要手段,并特别适合于一类业务系统的描述和处理,具有一定的实用价值。展开更多
基金the Project of Industrial Internet and Integration of Industrialization and Industrialization of Guangxi,China under Grant No.Guigong2021-37.
文摘This paper deals with the supervisory control problem of discrete event systems modeled by labeled Petri nets. The system is originally unbounded. First, the solvability of the problem is confirmed. A necessary condition is given and proven for the existence of a feasible priority-based controller based on the notions of liveness and transition invariants. Next, a cyclic behavior graph is constructed, which shows the reachable markings that guarantee the maximum liveness of the system within a given bound vector. Finally, an on-line control strategy is proposed to enforce boundedness and liveness to the given system by appending priority relations to transitions. The dynamic priority relation changes flexibly according to the current state of the system and enforces the system evolving in a bounded and live manner. In addition, numerical examples are studied to verify the validity of the proposed approach that remains the structure of the plant net and is efficient for on-line control.
基金the National Natural Science Foundation of China (No.60073013) and the NKBRSF of China (No.G1998030416).
文摘In this paper, the Extended Strong Asymmetric Choice Nets Ⅱ (ESACN Ⅱ), a subclass of Asymmetric Choice Nets (ACN) including Extended Free Choice Nets (EFCN) and Strong Asymmetric Choke Nets Ⅱ (SACN Ⅱ, is presented. A necessary and sufficient condition for liveness of ESACN Ⅱ is proposed. Moreover, a criterion is introduced, which is necessary and sufficient for judgement of liveness and boundedness of ESACN Ⅱ. Meanwhile a polynomial time algorithm is given to decide liveness and boundedness for ESACN Ⅱ.
文摘针对嵌入式系统建模问题,提出了一种经由扩展Petri网共享子网得到组合网的解决方案。将面向对象技术与嵌入式系统的Petri网表示模型(PRES网)融合,得到一种面向对象的PRES网—OOPRES(object-oriented petri net based representation for embedded system)网。提出了一种OOPRES网共享子网组合操作方法,并对其组合网系统的活性和有界性的保持问题进行了研究。以智能交通系统的建模分析为例验证了该组合方法的有效性。结果可为Petri网系统组合性质的考察提供有效途径,为大规模复杂嵌入式系统建模提供有利手段,具有宽广的应用前景。
文摘针对柔性制造系统的设计和分析,提出了经由 Petri 网共享子网构成合成网的解决方案;研究了 Petri 网共享子网合成的动态性质保持问题,给出了合成网保持活性、有界性的一组充分条件;对一个柔性制造系统进行了设计和分析。本文的结果可为 Petri 网系统静态和动态性质的考察提供有效途径,为 Petri 网复杂大系统的分析提供重要手段,并特别适合于柔性制造系统的设计,具有一定的实用价值。
文摘针对工厂用车间中的若干台机器加工某些部件等这一类业务处理问题,提出了用 Petri 网精细化操作解决问题的方案。定义了一种 PP-型子网,用这种子网分别对 Petri 网系统中的某些库所进行细化,得到更细致、更精确的Petri 网系统。研究了 Petri 网精细化操作的动态性质保持问题,给出这种精细化操作保持活性、有界性、可回复性和公平性的充要条件;本文的结果可为 Petri 网系统静态和动态性质的考察提供有效途径,为 Petri 网复杂大系统的分析提供重要手段,并特别适合于一类业务系统的描述和处理,具有一定的实用价值。
