I am reviewing a journal paper whose whole content is the same as a conference paper that the same authors published 2 years ago. If you publish a paper in a conference, can you publish it in a journal without a remarkable change?
I think the more pertinent question is why you would publish a conference paper without changing it. Bearing in mind that a public presentation is a test of the credibility of your ideas, I can't imagine why anyone would ignore valuable feedback.
This depends on several factors. 1. Was the publication after the conference a peer-reviewed one? Then I think you should ask the publishers of that conference proceedings volume whether it is ok. Have you signed away your copyright, then you most probably cannot. But check in any case. 2. If the publication at the conference was a serious one, then I believe that you should not try to publish exactly the same one elsewhere. It would seem unfair to the publishers and it is also unnecessary if one of the publications can be found by others - duplicating your research in order to boost ones CV is a no-no ... 2. On the other hand, if you have added a substantial part of the paper in your second "edition" of the paper, then it would be fair, I think. But then you need to change the name of the publication, and erase proofs, for example, from the previous one, and if there are any experiments made they would have to be new, both with respect to purpose and data.
I think the more pertinent question is why you would publish a conference paper without changing it. Bearing in mind that a public presentation is a test of the credibility of your ideas, I can't imagine why anyone would ignore valuable feedback.
I am reviewing a journal paper whose whole content is the same as a conference paper that the same authors published 2 years ago. I contacted them and the editor in chief to know how copy right works on this matter.
I think content may be same but there must be some difference in representation or it involve more data.Otherwise what remains the difference between a conference and a Journal Publication.