Small vegetated drainage ditches play an important role in water and nutrient removal, but may cause water blocking problems. The aim of this study was to investigate vegetated drainage ditches’ hydraulic and wetland hydraulic characters. Field experiment were carried out, small drainage ditches with Juncus, Zizania latifolia, and Acorus calamus were selected under different water flows, and a ...

We compare measured profiles of upper layer shear and rates of kinetic energy dissipation with the predictions of a one-dimensional turbulence model proposed by Craig and Banner (1994). Their formulation contains an unknown parameter, the "roughness length" z0, which we determine by fitting computed and observed dissipation rates. The resulting model, without further adjustment, is then used to...

Development of rural areas in rivers margins and flood plains, without understanding and attention to the dynamical and hydrological conditions and upstream areas of the rivers will cause to increase flood risk and loss of life and financial. Flood zoning has many applications, in floodplain management. For management of the three major branches of the Halilrood River, Rabor, Roodar and Javaran...

d image in the discrete cosine transform (DCT) omain can generate blocky artifacts in the outs a put image. It is possible to reduce these artifact nd RMS error by adjusting measures of block g t edginess and image roughness, while restrictin he DCT coefficient values to values that would d i have been quantized to those of the compresse mage. We also introduce a DCT coefficient . amplitude adj...

We study the numerical recovery of Manning’s roughness coefficient for the diffusive wave approximation of the shallow water equation. We describe a conjugate gradient method for the numerical inversion. Numerical results for one-dimensional model are presented to illustrate the feasibility of the approach. Also we provide a proof of the differentiability of the weak form with respect to the co...