The paper mentioned in the title proposed a new definition of increasing repetitive input sequences for synchronized Petri nets and stated that it can be used to construct a finite modified coverability graph for any unbounded SynPN. In this note, we discuss the notion of unboundedness for SynPNs and show via an example that actually the modified coverability graph may be infinite due the presence of increasing sequences that are not repetitive.

中文翻译：

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更正“使用同步 Petri 网在一类无界系统上同步序列”

标题中提到的论文为同步 Petri 网提出了增加重复输入序列的新定义，并指出它可用于为任何无界 SynPN 构建有限的修改覆盖图。在这篇笔记中，我们讨论了 SynPN 的无界概念，并通过一个例子表明，由于不重复的递增序列的存在，实际上修改后的覆盖图可能是无限的。