Q: Will my article be considered duplicate submission?
I intend to submit my research (in Japanese), that was previously presented at a conference, to the conference proceedings. I also intend to publish a journal article in English that summarizes the contents of my master’s thesis, to a miscellany issued by a laboratory. These two papers have some duplicate content. Will this be regarded as a duplicate submission?
From your question, it seems that you wish to publish your work at conference proceedings and the summary of your master’s thesis in a journal paper. You have also mentioned that these two articles have some overlapping content.
Typically, conference proceedings publish the scientific contributions presented by researchers at a conference. They are published either in print or in an online version.
The work that has been published as conference proceedings can be published as a journal article and this will not be considered a duplicate publication. You must ensure that you mention in the cover letter during your journal submission that this work has been previously published in conference proceedings and if possible provide a link to it. Also, ensure that the journal article has at least 30% new content and that its title is slightly different from that published in the conference proceedings.