Horizontal directional drilling (HDD) is widely used in soil and rock engineering. In a variety of conditions, it is necessary to estimate the torque required for performing the reaming operation. Nevertheless, there is not presently a convenient method to accomplish this task. In this paper, to overcome this difficulty based on the basic concepts of rock engineering systems (RES), a model for ...

In this work, quantitative structure-property relationship (QSPR) approaches were used to predict the redox potential of 42 phenolic antioxidants. The structures of all compounds optimized by the AM1 semi-empirical method and then a large number of molecular descriptors were calculated for each compound in the data set. Subsequently, stepwise multilinear regression was applied to select the mos...

in this work some quantitative structure activity relationship models were developed for prediction of three bioenvironmental parameters of 28 volatile organic compounds, which are used in assessing the behavior of pollutants in soil. these parameters are; half-life, non dimensional effective degradation rate constant and effective péclet number in two type of soil. the most effective descripto...

in this work, quantitative structure-property relationship (qspr) approaches were used to predict the redox potential of 42 phenolic antioxidants. the structures of all compounds optimized by the am1 semi-empirical method and then a large number of molecular descriptors were calculated for each compound in the data set. subsequently, stepwise multilinear regression was applied to select the mos...

in this study, response surface methodology was used to determine the optimum raw sugar beet juice purification process conditions using bentonite to produce inverted liquid sugar. for this purpose, impact of factors on the purification process such as bentonite concentration (1-5 gr/li), ph (3.5-6) and temperature (35-95 ˚c) was investigated. for each response, a second-order polynomial model ...