If, for example, you present a paper at a conference in Sydney, then, it seems to me, it shouldn't be the same paper you presented last year in Melbourne (albeit with a different title). Similarly, your Office of Research would probably be disappointed to learn that those two presentation entries in your research profile are really about one paper (presented twice). And, your Head of School/Department might also be disappointed to hear that those two round-trip airfares were both used to present one paper (twice).
(Such "recycling" can be academic dishonesty, but it's a nonsense to suggest that it's "self-plagiarism." There isn't such a thing. If it's wholey your own work, then it's not plagiarism.)
If there's a definitive guide on this subject, I'm unaware of it. Usually where academic dishonesty is addressed it's directed to student behaviour (the Northwestern Univeristy guide is an example.)
If you have a mentor who can lead you through the issues you're lucky. Offices of Research and Heads of School can be helpful in providing advice that will keep you away from trouble (but may vary in helping you to maximise the effect of you work). ▪
Only God can make a tree,
but only Mayor Daley can make a park.
—Chicago aphorism
