Solving optimization problems when designing power supply circuits O. V. Shemelova, E. V. Yakovleva, T. G. Makuseva, I. I. Eremina and O. N. Makusev E3S Web Conf., 124 (2019) 04011 Published online: 25 October 2019 DOI: 10.1051/e3sconf/201912404011