After the war she returned to Ukraine and in 1950, under the direction of Boris Gnedenko, she obtained a Ph.D. from the Institute of Mathematics of the Ukrainian Academy of Sciences.

For a period of seven years, Yushchenko held the position of Senior Researcher of the Kiev Institute of Mathematics of the Ukrainian SSR Academy of Sciences (1950–57).

During her forty years service to the institute, Yushchenko created an internationally notable scientific school of theoretical programming.

In the process of working with MESM, it became clear that the more complex tasks were difficult to solve by writing simple machine programs.

Kaluzhnin, a professor at Kyiv University, who taught a course on mathematical logic in the 1950–1970s, made a significant advancement in the understanding of this problem and formalized a scheme of interfacing with the program.

Part of these works have two to-three editions, and have been translated to more than 5 languages internationally, including German, Czech, Hungarian, French, Danish and so on.