This is the 736th most frequent Korean word.
의한
"Due to" or "based on."
The word '의한' is used to indicate that the decision was due to (or as a result of) the research.
그 결정은 연구에 의한 결과였다.
That decision was the result of research.
The word '의한' suggests that success is as a result of the effort.
우리는 노력에 의한 성공을 이룩했다.
We achieved success through effort.
In this context, '의한' explains that the change is caused by or due to the demands of people.