due to increasing importance of desertification challenges and its consequences the necessity of sustainabledevelopment achievement in arid and semi-arid regions is essential in order to avoid limited sources asting, increase the efficiency of controlling, reclamation and restoration projects of natural areas. based on the iterature review, it has been recognized that combating desertification ...

existence of heavy minerals in waters in some regions causes serious environmental pollution and affects the soil and water resources quality. soil and waters sensitive to pollutants were investigated in this research, based on the degree of sensitivity of their parameters. the samples obtained from industrial and agricultural areas for identifying water tables at higher risk and display region...

control of sedimentation in dam reservoirs is considered to be one of the most important issues in exploitation of dams and increasing the their useful life. reservoirs act as traps for sediments and prevent transport of sediment to the river. the deposited sediment decreases the capacity of reservoirs so that they can not be in use any more. various methods dealing with removing part of the de...

in the present study a quasi 2-d numerical model is developed for calculating air concentration distribution in rapid flows. the model solves air continuity equation (convection diffusion equation) in the whole flow domain. this solution is then coupled with calculations of the free surface in which air content in the flow is also considered. to verify the model, its results are compared with a...

open-channel junctions have a broad application in civil and environmental engineering. formation of a low-pressure zone with recirculating flow (high sedimentation) accompanied by a high-velocity zone (high erosion) is the most characteristic feature of flow in junctions. a large number of researches have been performed to study the complexity of the flow in junctions in open-channel flows. in...

in this paper we investigate a nonlinear evolution model described by the rosenau-kdv equation. we propose a three-level average implicit finite difference scheme for its numerical solutions and prove that this scheme is stable and convergent in the order of o(τ2 + h2). furthermore we show the existence and uniqueness of numerical solutions. comparing the numerical results with other methods in...

breaking waves have ability to transport large quantities of sediment and significant impact on coastal structures morphology. hence, modeling of wave breaking is an important subject in coastal and marine engineering. in this research, the periodic wave breaking process on a plane slope is studied experimentally and numerically. laboratory experiments were conducted to record water surface ele...

due to increasing importance of desertification challenges and its consequences the necessity of sustainabledevelopment achievement in arid and semi-arid regions is essential in order to avoid limited sources asting, increase the efficiency of controlling, reclamation and restoration projects of natural areas. based on the iterature review, it has been recognized that combating desertification ...

the performance of water flooding can be investigated by using either detail numerical modeling or simulation, or simply through the analytical buckley-leverett (bl) model. the buckley-leverett analytical technique can be applied to one-dimensional homogeneous systems. in this paper, the impact of heterogeneity on water flooding performance and fractional flow curve is investigated. first, a ba...

the pile-raft foundation is a combination of a raft foundation with piles. pile-raft foundation has been widely designed, assuming all structure loads to be transferred to piles without considering contribution of the load taken by contact surface between raft and soil. methods of analysis currently used in practice are based upon relatively conservative assumptions of soil behavior or on the l...