in this study, scour of mashkid bridge pier located in mashkid river of saravan county has been studied and to measure the scour rate, the numerical model hec-ras 4.0 has been used. upon selection of mashkid river as the case study and whereas the studied zone is important with respect to the climatic conditions and showery monsoon raining and flowing the great and destructive floodwaters, ther...

Cultivating rangeland to be shifted to crop land farms commonly causes soil degradation and runoff generation. This study was conducted to evaluate the cultivation effects on runoff generation and soil quality. The experiment was performed in a rangeland and a 40-year cultivated land located at two slope positions (back slope and shoulder) of a hillside in Dorahan, Chaharmahal & Bakhtiari Provi...

there has been a gradual shift of focus from the study of rule systems, which have increasingly been regarded as impoverished, … to the study of systems of principles, which appear to occupy a much more central position in determining the character and variety of possible human languages. there is a set of absolute universals, notions and principles existing in ug which do not vary from one ...

with the increasing population and the need for more food, as well as with the development of science and technology, human approach to unnatural and often chemical inputs to increase agricultural production has been a great expansion and problems such as increased cancers, chronic diseases has created environmental pollution. implementation of organic organic is a solution to these problems . ...

 Studying climate change impact on hydrological variables such as runoff has attracted more attention over recent years mainly due to the imposed imbalance in climate system by greenhouse gas emission. Hence, initially in this research, the trend and abrupt changes of hydro – climatic variables were studied using data mining approaches in 18 stations over 40 years (1972-2011) in Aji-Chai waters...

Nowadays, organic mulches are used as protective cover for the soil surface.This study in order to investigate the effect of protective cover straw Colza on the components of start time and runoff coefficient in loam – sandy soil in laboratory scale and using a rain simulation with an intensity of 50 mm / h with a 10-minute duration has been done. For this purpose, three levels of protective co...

Cultivating rangeland to be shifted to crop land farms commonly causes soil degradation and runoff generation. This study was conducted to evaluate the cultivation effects on runoff generation and soil quality. The experiment was performed in a rangeland and a 40-year cultivated land located at two slope positions (back slope and shoulder) of a hillside in Dorahan, Chaharmahal & Bakhtiari Provi...

in civil engineering concrete is a material combined of hydraulic cement, sand, gravel and water. gravel and sand compose 60 to 70 percent of concrete. these aggregates support compression force of concrete. cement paste acts as glue to stick grain together. in bushehr factories producing aggregates do not operate according to astm standards, so that fineness modulus (fm) of the produced sands ...