in this paper the use of farm machinery in sugar beet farms in farsprovince was studied. the necessary data, with two-stage cluster sampling method in fasa, eghlid and darab cities on 2004- 2005 were collected. from 203 farmers selected for the study. 113 of them were in high level mechanization group and 90 of them were in low level mechanization group. in this study, the effect of farm machin...

Discussions of technological change have offered sharply contrasting perspectives of technological change as gradual or incremental and the image of technological change as being rapid, even discontinuous. These alternative perspectives are bridged using the punctuated equilibrium framework of evolutionary biology. Using this framework, it is argued that the critical event is not a transformati...