The Ganui (簡儀, simplified armillary sphere) is a representative of astronomical instruments in Joseon Dynasty of Korea, as well as Yuan Dynasty and Ming Dynasty of China. In early 15th century, Joseon's scientists and engineers uniquely developed the Soganui (小簡儀, small simplified armillary sphere) and the Ilseongjeongsiui (日星定時儀, sun-and-star time determining instrument) from the structural characteristic of Ganui. These two astronomical instruments had a new design by the miniaturization and felt convinced a similar performance of Ganui in the harmony with Korean Astronomy and Astrology Cultures. Since mid-18th century after the enforcement of shixian-li (時憲曆), the Soganui and Ilseongjeongsiui handed over the Jeokdogyeongwiui (赤道經緯儀, equatorial armilla) by a change of the observational framework such as the time and angle measures. The Jeokdogyeongwiui made by Gwansanggam (觀象監, Bureau of Astronomy in Joseon Dynasty) adopted the new observational framework. We studied the structural characteristics and scientific values of these 3 astronomical instruments with theirs observation methods.

ABSTRACT
1. 서론
2. 간의의 제작과 새로운 창제
    2.1. 간의 구조와 사용법
    2.2. 소간의와 일성정시의 창제
    2.3. 소간의와 일성정시의에 도입된 구조 변화
3. 서양식 관측기기의 응용
    3.1. 적도경위의의 제작
    3.2. 적도경위의의 구조와 사용법
4. 조선관측기기의 구조 혁신과 실용화
참고 문헌

• 김상혁(한국천문연구원) | SANG HYUK KIM (Korea Astronomy and Space Science Institute)
• 민병희(한국천문연구원, 충북대학교) | BYEONG-HEE MIHN (Korea Astronomy and Space Science Institute, Chungbuk National University)
• 이민수(충북대학교 천문대) | MIN SOO LEE (Chungbuk National University Observatory)
• 이용삼(충북대학교 천문대) | YONG SAM LEE (Chungbuk National University Observatory)