Simultaneous comparison of the effects of shaft load and shaft positions on tractor OEE in two soil conditions (cultivated and uncultivated) Journal title: International Journal of Farming and Allied Sciences Authors: Amin Samiei Far, Navab kazemi, Majid Rahnama and Mahmood Ghasemi nejad Subject(s): Agricultural Science, Biochemistry, Plant Sciences, Soil Sciences, Zoology and Animal Science, Agricultural Economics