This paper explored numerical techniques to simulate the movement of an applied tracer plume in a laboratory beach subjected to tide. The MARUN model (Boufadel et al., 1999) was used. The movement of the tracer plume in the beach and the development of a transient seepage on the beach surface were modeled. By calibrating the results of the numerical model against the observed data, the laborato...

Despite improved endotracheal tube designs, aspiration remains a cause of pulmonary complications. This in vitro study evaluates the efficacy of positive end-expiratory pressure (PEEP) in reducing the incidence of seepage around endotracheal tubes during mechanical (MV) and spontaneous ventilation (SV). Two transparent plastic "tracheas" with cuffed and uncuffed endotracheal tubes simulated adu...

The classical formulation of the coupled hydroelectrical flow in porous media is based on a linear formulation of two coupled constitutive equations for the electrical current density and the seepage velocity of the water phase and obeying Onsager’s reciprocity. This formulation shows that the streaming current density is controlled by the gradient of the fluid pressure of the water phase and a...

A novel discrete singular convolution (DSC)  formulation  is  presented for the seepage analysis in irregular geometric porous media. The DSC is a new promising numerical approach which has been recently applied to solve several engineering problems. For a medium with regular geometry, realizing of the DSC for the seepage analysis is straight forward. But DSC implementation for a medium with ir...

In the last three decades the design of stepped spillways regained some interest because of their suitability with new construction methods including gabion placement. In this study, the hydraulic performances of gabion stepped weirs were investigated experimentally in terms of the air-water flow properties and energy dissipation rate. A physical study was performed in a relatively large size f...

Multi-objective optimization was used to calibrate a regional surface water-groundwater model of the Yaqui Valley, a 6800 km2 irrigated agricultural region located along the Sea of Cortez in Sonora, Mexico. The model simulates three-dimensional groundwater flow coupled to onedimensional surface water flow in the irrigation canals. It accounts for the spatial distribution of annual recharge from...

[1] We present a method for determining streambed seepage rates using time series thermal data. The new method is based on quantifying changes in phase and amplitude of temperature variations between pairs of subsurface sensors. For a reasonable range of streambed thermal properties and sensor spacings the time series method should allow reliable estimation of seepage rates for a range of at le...

The re-emergence of groundwater at the surface shapes the Earth’s topography through a process known as seepage erosion1–5. In combination with flow over land6, seepage erosion contributes to the initiation and growth of channel networks1–5. Seepage processes have also been invoked in the formation of enigmatic amphitheatre-headed channel networks on both Earth7–11 and Mars12–14. However, the r...

Alkanes are major constituents of crude oil and are released to the marine environment by natural seepage and from anthropogenic sources. Due to their chemical inertness, their removal from anoxic marine sediments is primarily controlled by the activity of anaerobic alkane-degrading microorganisms. To facilitate comprehensive cultivation-independent surveys of the diversity and distribution of ...