Rim worked as a researcher at the Global Environment Information Institute under the State Academy of Sciences.

After graduating from Kim Il Sung University, he became a geographer, determined to contribute to building a prosperous country with science and technology.

As a member of the group for exploring Lake Chon on Mt. Paektu, he devoted his wisdom and energy to the survey of this sacred mountain of the Korean revolution.

During the days of the survey, he deciphered and confirmed on a scientific and technological basis the age of eruptions on the mountain, the area and boundary of the Paektu lava plateau and the quality of water on Lake Samji.

He verified the frequency of Paektu volcano eruption and its scale and drew up a document on its history, providing basic data for volcano and earthquake forecast.

He also completed a Mt. Paektu geological chart early in the 1980s.

Besides, he successfully made surveys of the sea surface change of Korea and Mts. Kumgang and Chilbo.

In over 55 years, Rim authored more than 60 books as valuable as national treasure, including "Encyclopedia of Mt. Paektu" (topography), and about 70 papers and trained tens of persons to be winners of academic degrees or titles.

The government awarded titles of candidate academician, professorship and doctorate to him in recognition of his merits.