In case I upload an unpublished conference paper or technical report of mine to Academia.edu is it protected from plagiarism? I would like to know if an uploaded unpublished paper of mine it is safe from plagiarism, including just parts of it (e.g. title). 

I meant that if somebody copies part or the entire unpublished, but already online, document and publishes it, is he/she then liable of plagiarism?
Liability for plagiarism does not depend on whether the plagiarized work was published or not. 

If somebody uses your work and passes it off as their own work, it's plagiarism.