coriandrum sativum l. is one of the most important plants compared to the other herbs and medicinal plants as a planted covered area in kermanshah province. for a suitable irrigation management programming, the awareness of crop coefficient and water requirement in different plant stages is essential. the ratio of actual evapotranspiration to reference crop evapotranspiration is defined as crop...

Evapotranspiration (ET) is one of the major components of hydrologic cycle. Accurate estimation of this parameter is essential for studies such as water balance, irrigation system design and management, and water resources management. Generally we used climate data for calculating evapotranspiration from indirect methods. This study investigates the utility of artificial neural networks (ANNs) ...

The proposed method for calculation of potential evapotranspiration is Penman-Monteith FAO method, but there are other methods that require less meteorological data but estimates close to the FAO Penman-Monteith method in different climatic conditions.  Performance evaluation of these methods on the same basis is prerequisite for selecting an alternative approach in accordance with available da...

abstract evapotranspiration (et) is one of the most important components of the water balance, it is also one of the most difficult to measure. despite the importance of et, methods to obtain values of et are still limited. conventional methods are very local, ranging from point to field scale. estimates of the et over the entire area, especially for irrigated areas, are essential, as these can...

from the mathematical point of view, the fao penman-monteith equation shows a homographic function related to the wind speed. the homographic function has horizontal and vertical asymptotes. in this issue horizontal asymptote is applicable; because the vertical asymptote occurs for negative values of wind speed but the negative sign indicates the direction of the wind speed and only the absolut...