%0 Journal Article %T Efficient operation of the tractor in the unit with machine a variable mass %A Shulyak, M.. %K tractor, workflow, the fuel consumption, variable mas. %J Actual directions of scientific researches of the XXI century: theory and practice %D 2015 %N 3 %P 3 %I FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov