Complex sentence: It stands for "Машина для Инженерных Расчётов" (Computer for Enngineering Applications) and was designed as a relatively small-scale (for that time) computer for use in engineering and scientific applications.
Split into simpler sentences: It stands for "Машина для Инженерных Расчётов" (Computer for Engineering Applications). It was designed as a relatively small-scale computer for use in engineering and scientific applications.