Search results for "Distributed element model"
showing 10 items of 11 documents
Exploring calibration strategies of the SEDD model in two olive orchard catchments
2017
To optimize soil conservation strategies in catchments, it is required an accurate diagnosis of the areas contributing to soil erosion by using models such as SEDD (Sediment Delivery Distributed model). In this study, different calibration strategies of the SEDD model were explored to adapt its use in two olive catchments with different environmental features and managements. A data series of rainfall–runoff–sediment load, collected in the catchments for 6 years was used: i) to evaluate calibration strategies for different management and flow conditions through the analysis of the C and R factors, and ii) to describe the temporal patterns of sediment delivery ratio (SDR) at the event and an…
New distributed model for synthesis of classical dual mode filters
2010
Up to now, distributed models for classical dual mode filters have not been developed. In this paper, the whole procedure to derive such distributed models is shown step by step. The resulting formulas are very similar to those standard ones used for in-line filters since the 1960s. Model limitations, very similar to those related to classical formulas, in terms of precision and bandwidth, are pointed out. Finally, two practical examples of distributed models of dual mode filters for satellite transponders with different orders have been extracted.
Monitoring and predicting sediment yield in a small Sicilian basin
2001
Identifying areas of a basin that are most sensitive to erosion have stimulated the study of within–basin variability of the sediment–delivery processes and the use of spatially distributed models. To verify the reliability of a sediment–delivery distributed model applicable at the morphological unit scale (i.e., the area of clearly defined aspect, length, and steepness), experiments were carried out at mean annual and event scales in a small Sicilian basin. A Geographical Information System is briefly presented into which the measurements carried out at the basin outlet (runoff, sediment yield, etc.) and other point and areal information (soil erodibility, digital terrain model, etc.) were…
Exploiting the topographic information in a PDM-based conceptual hydrological model
2014
In this work, a conceptual lumped model was developed to simulate runoff and analyze hydrological processes with the goal of incorporating the morphological information into a probability-distributed model (PDM). PDMs usually describe the process of runoff generation as the result of soil saturation excess caused by precipitation with soil storage capacity represented by a spatially distributed quantity and described by a probability distribution. The proposed model, called topography-based probability distributed model (TOPDM), based on a simple water balance whose components are basin soil moisture storage, precipitation, drainage to groundwater, evapotranspiration, and Dunnian and Horton…
Surge instability in a distributed parameter radial compression system
1995
Turbocompressor surge in a line with a long suction duct and plenum chamber is analysed using a distributed parameter propagation model which accounts for dynamic damping. The results, though obtained with simplifying assumptions, show very good agreement with experimental data.
Testing Sediment Connectivity at the Experimental SPA2 Basin, Sicily (Italy)
2017
The concept of sediment delivery can be used as a measure of sediment connectivity, and it can be linked to the structural connectivity (morphological unit, slope length, slope steepness, travel time) of a basin and to the hydrological connectivity (rainfall–runoff processes at morphological unit scale). In this paper, the sediment connectivity concept was tested at basin scale applying SEdiment Delivery Distributed model, which takes into account the hillslope sediment transport, and using sediment yield measurements carried out at SPA2 experimental basin (Sicily, Italy). For the SPA2 basin discretized into morphological units, the SEdiment Delivery Distributed model was first calibrated a…
Length Slope Factors for applying the Revised Universal Soil Loss Equation at Basin Scale in Southern Italy
2000
In this paper, for a basin divided into morphological units, a distributed model based on the Revised Universal Soil Loss Equation (RUSLE), with different expressions for the topographic factors, and on the sediment delivery ratio of each morphological unit is used. At first, the caesium-137 data available from a Sicilian basin are calibrated with two different models [the Proportional Method (PM), the Simplified Mass Balance (SMB) model] to provide net soil loss data for each morphological unit. Then, for a selected expression of the topographic factor, the slope length exponent is calculated for each morphological unit, equating the calculated sediment yield with the net soil loss. The an…
Linking sediment yield and caesium-137 spatial distribution at basin scale
1999
Abstract Identifying areas of the landscape that are most sensitive or susceptible to erosion stimulated the study of within-basin variability of the sediment delivery processes and the use of spatially distributed models coupled with Geographic Information Systems. The progress of sediment delivery distributed modelling is also dependent on the availability of measurements able to establish the link between eroded soil leaving an area and the patterns of erosion and deposition occurring along the hydraulic path from the considered area to the nearest stream reach. In this paper, the tracer technique using the radionuclide137Cs and its employment in sediment yield studies at basin scale are…
Derivation of a Distributed Unit Hydrograph Integrating GIS and Remote Sensing
2007
The paper describes the results of a study based on the integration of remote sensing and geographical information system techniques to evaluate a distributed unit hydrograph model linked to an excess rainfall model for estimating the streamflow response at the outlet of a watershed. Travel time computation, based on the definition of a distributed unit hydrograph, has been performed, implementing a procedure using (1) a cell-to-cell flow path through the landscape determined from a digital elevation model (DEM); and (2) roughness parameters obtained from remote sensing data. This procedure allows the taking into account of the differences, in terms of velocity, between the hillslopes and t…
Evaluation of the SEDD model for predicting sediment yield at the Sicilian experimental SPA2 basin
2007
In this paper a spatially distributed model of the hillslope sediment delivery processes, named the sediment delivery distributed (SEDD) model, is initially reviewed; the model takes into account the sediment delivery processes due to both the hillslope sediment transport and the effects of slope curvature. Then the rainfall and sediment yield events measured at the experimental SPA2 basin, in Sicily, are used both to calibrate the SEDD model and to verify the predictive capability of the distributed sediment delivery approach at event scale. For the SPA2 basin discretized into morphological units and stream tubes, the SEDD model is calibrated at event scale using the measurements carried o…