E.Ya.Khruslov. On the occasion of his 70th birthday

On January 7, 2007 Evgueni Yakovlevich Khruslov, a prominent mathematician, Academician of the National Academy of Science of Ukraine, celebrated his 70th birthday. Evgueni Khruslov was born in Kharkov, Ukraine. In 1954 he graduated from a high school at a city’s suburb. When studying at the school, he preferred exact sciences, like physics and mathematics. However, at the time of graduation, he could not imagine mathematics to be his future professional occupation, and thus he chose a technical college, the Kharkov Polytechnic Institute, to continue the education. After graduating from the Polytechnic Institute in 1959, he started to work as an electrical engineer at an automation research institute. At that time, Gleb Klyagin, a man of an extraordinary destiny, was working there. Before the World War II, Klyagin itself was very interested in mathematics, but as soon as the war began, he joined the regular army and after a while he was sent by plane to help guerrilla groups in Yugoslavia and Slovakia. After the war, Klyagin graduated from the Kharkov Polytechnic Institute and worked at that institute where Khruslov was directed. Being a man of observation, Klyagin could not miss mathematical abilities of a new employee. He saw that his colleagues continuously addressed Evgueni Khruslov with difficult mathematical problems. So, Klyagin decided to interfere in Khruslov’s destiny and to tell about the young man to his old classmate, professor of mathematics Vladimir Marchenko. They agreed that Khruslov and Marchenko would speak, and then they would see. Thus Evgueni Khruslov met Vladimir Marchenko for the first time, and that meeting was the beginning of a long collaboration and friendship. At that time, experts from the Kharkov Turbine Plant asked Marchenko to help in solving an applied problem concerning the determination of an optimal profile of turbine buckets. Taking into account the engineer specialization of Khruslov, Marchenko proposed to him to think about this problem. Notice that Khruslov did