abstract one of the losses decrease's ways in fields, is the proper irrigation management, which its base is the accurate estimation of crop water requirement. equations which are used to calculate the reference evapotranspiration (eto), do not use the same climatic parameters and due to their empirical base, are not match to all climatic situations. so it is needed to clarify proper methods fo...

estimating and determining of rice water requirement, being the main cultivate of rasht region, is crucial for devoting water to this region. equations which are used to calculate the reference evapotranspiration (et0) are not match to all climatic conditions, due to their empirical bases. so, it is necessary to clarify proper methods for each region. crop coefficient (kc) is also the main para...

In this paper, the Kadomtsev-Petviashvili equation is solved by using the Adomian’s decomposition method , modified Adomian’s decomposition method , variational iteration method , modified variational iteration method, homotopy perturbation method, modified homotopy perturbation method and homotopy analysis method. The existence and uniqueness of the solution and convergence of the proposed...

The modified generalized Van der Pol-Mathieu equation is generalization of the equation that is investigated by authors Momeni et al. (2007), Veerman and Verhulst (2009) and Kadeřábek (2012). In this article the Bautin bifurcation of the autonomous system associated with the modified generalized Van der Pol-Mathieu equation has been proved. The existence of limit cycles is studied and the Lyapu...

High-temperature tensile testing of AH36 material in a wide range of temperatures (1173-1573 K) and strain rates (10-4-10-2 s-1) has been obtained by using a Gleeble system. These experimental stress-strain data have been adopted to develop the constitutive equation. The constitutive equation of AH36 material was suggested based on the modified Arrhenius-type equation and the modified Rossard e...

In this paper, the modified simplest equation method is successfully implemented to find travelling wave solutions of the generalized forms $B(n,1)$ and $B(-n,1)$ of Burgers equation. This method is direct, effective and easy to calculate, and it is a powerful mathematical tool for obtaining exact travelling wave solutions of the generalized forms $B(n,1)$ and $B(-n,1)$ of Burgers equation and ...

This study uses two forms of the Palmer Drought Severity Index (PDSI), namely PDSI_TH (potential evapotranspiration estimated-by Thornthwaite equation) and PDSI_PM estimated by FAO Penman-Monteith equation), to characterize meteorological drought trends during 1960–2016 in Loess Plateau (LP) its four subregions. By designing a series numerical experiments, we mainly investigated various climati...