I wonder if there is a deadline for submission to a journal? So far, I only know that submission to conferences has a deadline, but I'm not sure about journals.
I've looked at several journals of Elsevier, IEEE, and Springer, and I cannot find any information about the deadlines. I did some search on Google and understand the process as follows:
One journal may publish multiple issues per year. If at the moment I submit a paper to a journal and miss the deadline of the current issues (which I do not know of), my paper will be reviewed for the next one.
Although there is no "fixed" deadline, but if I submit a paper and it is to be revised, I will then have some amount of time to finish the revision - so that's some sort of deadline, but it's relative to each paper.
Another question is that, as a Ph.D. student in machine learning/artificial intelligence, should I focus more on conferences or journals? It's been 6 months since I started my Ph.D. and I haven't published anything. In France, a Ph.D. lasts for only 3 years and my doctorate school demands at least 4 papers published from a "successful" Ph.D. student. Should I start worrying now?
Thank you very much!