EFFICIENCY EVALUATION OF IMPLEMENTATION OF OPTIMIZATION METHODS OF OPERATION MODES OF THE "PLAST - GAS PIPELINE" SYSTEM BY THE METHODS OF MATHEMATICAL MODELING Journal title: EUREKA: Physics and Engineering Authors: Oleksandr Filipchuk, Victor Marushchenko, Mikhailo Bratakh, Myroslav Savchuk, Safaa Tarwat Subject(s): Astronomy/Astrophysics/Space Science, Computer and Information Science, Electrical and Electronic Engineering, Engineering, Physics, Chemical Engineering, Energy, Mechanical Engineering