Do you mean some organizers allow authors to republish previous article without the permit from the publisher(s)/conference organizer(s)?

There is a reply (www.5gh.org.cn/WuGH/2025/00...) from the authors. The 5GH Team appreciates the clarification by Dr. Payne.

I have two questions: (1) What criteria should I look for to determine whether a publisher/journal is predatory? (2) What actions can be taken if it is a predatory publisher?

You can also find the extracted data in the Excel file at: www.5gh.org.cn/WuGH/2025/00...

(2/2) The data extracted is shown in lower-left panel, the reproduced Tauc plot is shown in the lower-right panel, while the original Tauc plot is shown in the upper-right panel.

(2/2) If you have any information or leads regarding hijacked Chinese journals, please feel free to @ me, send me a direct message, or email me at wu[at]5gh.org.cn. Thank you very much!