grade control structures are hydraulic structures used to stabilize a river bed. scour downstream of this structure is the main cause of its failure. studies have developed numerous empirical relations for scour depth prediction that designers must choose between to decide the most effective equation for a specific application. this study tested the condition of submerged jets over beds of sedi...

we apply the two-sector production function developed by ram (1986) to estimate the threshold regression model for iran, concerning the effect of government size on economic growth. three government size indicators are used to find out the different threshold points. the results show a non-linear relationship of the armey curve in iran, in which the threshold effects corresponding to total gove...

In the present study, the possibility of concentrating tungsten-copper vein ore in South Chah-Palang was examined using gravity separators including Jig Machine (-2360+600 μm), shaking table (-600+120 μm), and multi-gravity separator (MGS) (-120 μm). The representative sample contains 1.5% WO3 and 5.95% CuO. The main tungsten minerals were ferberite and wolframite and their appropriate liberati...

The important technological and economic advantages have expanded the use of shoe press technology to the dewatering of all paper products from pulp to tissue. Whereas the development of NipcoFlex technology began in packaging paper machines 20 years ago, this technology can today be found in virtually all applications for the mechanical dewatering of the paper web in new and modernized product...

In this study based on image analysis, an ore grade estimation model was developed. The study was performed at a limestone mine in central Iran. The samples were collected from different parts of the mine and crushed in size from 2.58 cm down to 15 cm. The images of the samples were taken in appropriate environment and processed. A total of 76 features were extracted from the identified rock sa...

background: prognostic models have clinical appeal to aid therapeutic decision making. two main practical challenges in development of such models are assessment of validity of models and imputation of missing data. in this study, importance of imputation of missing data and application of bootstrap technique in development, simplification, and assessment of internal validity of a prognostic mo...