How to choose romanization for non-Latin script in an otherwise Latin script text? While combing through English journal articles and semi-scientific articles, I noticed how problematic it is that in some cases those papers use a romanized, Latin script display of originally Non-Latin script words and expressions. The issue: In my case (Korean), there were several revisions of the romanization system and some of the texts I work with are either (a) older or (b) the authors simply don't comply to the correct romanization standards. Thus it is very hard (at least for me) to derive the original non-latin script (which is my goal) from an incorrect romanization.

Additionally, in many cases it is beneficial or even crucial to have access to not only the Hangeul, but also the Hanja, i.e. Chinese characters. At least that is my opinion.

Because I assert that only if I mention the Non-Latin script (in this case Hangeul/Hanja) "as is", can my academic work be precise, exact and unambiguous.

What do you think about that? Are there any standard rules for such a situation, that are widely used (i.e. expected from students and academics), e.g. in the USA?

Finally: Would there be cases in which you would not use the romanized, Latin Script text version at all? (Assuming that we only talk about a few (5-10) words per page.)

Note: The academic results I produce won't be published in any (international) journal anytime soon, but I still would like to follow the highest standard possible, without sacrificing common sense and preciseness.
For things that you won't publish, you can adhere to a standard you choose, for example writing in the Korean script using LaTeX.

It's difficult to talk more specifically than that because journals have their own requirements, which can have more to do with their typesetting systems than academic rigor. 

If a journal publishes your work with ambiguous transliteration, you may be able to keep an alternate copy on ArXiV. (N.B. I'm not sure it's kosher to do this but I suspect it's fine as long as the alternate version is designated carefully.)