rails fracture by the growth of fatigue crack or critical crack is one of the prevalent defects in railway. the rail fracture, failure and stress analysis should be studied in order to prevention of rail fracture. in this paper, new formulation of contact stress for two rolling bodies is presented, where the results are closed to the hertz stress formulation. moreover, stress analysis is done b...

understanding the relationship between root yield and other traits in sugar beet may be a crucial step towards successful breeding of this important crop. path analysis provides a useful method in analyzing the genetic and phenotypic coefficients of correlations. this method is able to effectively unveil direct and indirect effects among traits of interest. in this research, root yield, yield c...

It is well known that disability rates among the American elderly have declined over the past decades. The cause of this decline is less well established. In this paper, we test one important possible explanation--that the decline in disability occurred because of chronic disease prevention efforts among the elderly. For this purpose we analyze data from the National Long Term Care Survey and f...

Introduction: Unit risk management is a critical component of gas refining management, as risks that are not well-managed may lead to trip production failures. The present study aimed to provide a structural model for investigating the role and effect of different variables on stopping the gas production process in the gas refinery. Material and Methods: This study was a retrospective cross-se...

abstract     in order to study the relationships among seed yield and its components in nigella sativa, path coefficient and factor analysis was done using some agro- morphological traits of 21 different genotypes. genotypes were evaluated using a completely randomized design with four replications in ardestan university research farms. there was a high and positive correlation between seed yie...