The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. http://http://dspace.unitus.it:80 2013-06-19T20:16:58Z 2013-06-19T20:16:58Z Petroselli, Andrea Nardi, Fernando Santini, Monia Grimaldi, Salvatore Ubertini, Lucio http://hdl.handle.net/2067/1528 2011-07-18T13:18:20Z 2007-12-31T23:00:00Z

Title: Confronto tra alcuni metodi per l’estrazione del reticolo idrografico da DEM affetti da aree piane Authors: Petroselli, Andrea; Nardi, Fernando; Santini, Monia; Grimaldi, Salvatore; Ubertini, Lucio Abstract: In questo lavoro si analizzano alcuni metodi per la definizione delle direzioni di deflusso e per il trattamento delle aree piane dei Digital Elevation Model (DEM). La procedura presente nei più utilizzati pacchetti software (ESRI ArcInfo e GRASS) viene confrontata con alcune tecniche recentemente proposte in letteratura, analizzando i risultati ottenuti su un sottobacino del Fiume Tevere. Il confronto viene svolto sia stimando alcuni parametri idro-geomorfologici, ma soprattutto valutando diverse grandezze di progetto delle analisi idrologiche più comuni.; In this manuscript some DEM-based flow-direction methods and flat area treatment approaches are investigated. The standard procedure of widely used GIS software packages (ESRI ArcInfo and GRASS) is compared to some new recently proposed techniques analysing results obtained on a small sub-basin of the Tiber river. Differences of the new experimental procedures as respect to the standard approach are evaluated in term of some hydrogeomorphic variables and other hydrological design parameters.

2007-12-31T23:00:00Z Nardi, Fernando Grimaldi, Salvatore Santini, Monia Petroselli, Andrea Ubertini, Lucio http://hdl.handle.net/2067/1419 2011-06-27T18:05:06Z 2007-12-31T23:00:00Z

Title: Hydrogeomorphic properties of simulated drainage patterns using digital elevation models: the flat area issue Authors: Nardi, Fernando; Grimaldi, Salvatore; Santini, Monia; Petroselli, Andrea; Ubertini, Lucio Abstract: Flat areas are a critical issue for the characterization of drainage patterns using digital elevation models (DEM). In this work, flat area removal and flow direction algorithms are implemented, and also a physically-based DEM correction model is introduced, for investigating their influence on the topological properties of the channel network, the Hortonian parameters and the hillslope width function. Differences of results, as compared to the standard procedures implemented in widely-used GIS-based hydrological packages, show the importance for hydrogeomorphic modellers to consider the use of more detailed approaches.; Les zones planes sont problématiques pour l’interprétation des modèles numériques de terrain (MNT) en termes de caractérisation des réseaux de drainage. Dans cette étude, des algorithmes de suppression des zones planes et d’analyse des directions d’écoulement sont implémentés, dont un nouveau modèle à bases physiques de correction de MNT, afin d’étudier leur influence sur les propriétés topologiques du réseau hydrographique, les paramètres de Horton et la fonction largeur de versant. Les différences de résultats, lors de la comparaison avec les procédures standard implémentées dans les modules hydrologiques courants sous SIG, montrent l’importance pour les modélisateurs hydro-géomorphologues d’envisager d’utiliser des approches plus détaillées. Description: L'articolo è disponibile sul sito dell'editore http://www.tandfonline.com/

2007-12-31T23:00:00Z