I also checked 検出の原理 (kenshutsu no genri) in Google Translate before looking at the comments.

The kanji that gave me the hardest time to type was the 出. It’s not 出 listed as a 5-stroke radical in my computer, and my other radical guess, 山, doesn’t have it in the +2 strokes list (and I’m baka gaijin enough to not know the reading of a first grade kanji without looking it up).