Q: Can an article presented at a conference and one submitted to a journal have the same title?

It is a common practice to present the same study at a conference and later publish it in a journal. Generally, a preliminary analysis is presented at the conference. Once you receive feedback on your study at the conference, you might want to incorporate some of them in the manuscript that you prepare for journal submission. Thus, the paper that you will submit to the journal will be an improved and a more detailed version of the one you presented at the conference. 

It is advisable to change the title of the paper before you submit it to a journal. This is because the conference abstract may be published in the conference proceedings and having a different title would ensure that readers don't confuse between the published conference abstract and journal article. 

Additionally, most journals require at least 30 per cent new content from the version presented at the conference, therefore, some amount of revisions are required.  There is usually no time limit within which you need to publish the journal paper, but once you have presented the findings at a conference, you wouldn't want to delay it too long. Also, please go through the submission policy for previously published conference papers that are usually provided under author guidelines of your target journal and make sure your paper follows all the guidelines.

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