Prof. Zhang Rui-Kai (1945-), vice director of Chinese Water Conservancy Academic Committee, a member of International Association of Hydrological Research (IAHR), a member of specialist group on hydrologic surveying and mapping assessment of the Degree Management Office of the State Council of the People's Republic of China, director of Navigation Committee of Chinese Waterpower Engineering Academic Committee. He led more than 40 projects funded by the state key scientific issues program, National Nature Foundation and scientific researching programs sponsored by provinces or ministries. He wrote over 60 monographs, papers and research reports. He won the second-class prize of National Science and Technology Advancement Award twice, the first-class prize of Ministry Science and Technology Advancement Award once, the second-class prize three times, and the award for major achievements in the "Eighth Five-Year" of China. He was granted the title of excellent scientific researcher of national transportation sector. The project that is led by him and funded by National Nature Foundation was assessed as the top quality. He is the first one proposing the calculation method of growth rate of initial influx during the transmission of water in ship-locks, and the method has become the standard calculation method. He research results on the correction of down-scaling effect on Ship-lock hydro-dynamic model, ship navigation condition simulator, numerical multi-tube water transmission model for ship-locks, and operation reliability analysis of ship-locks still hold the leading place at home and abroad.