Documents disponibles écrits par cet auteur

Multifractal characterization of water-worked gravel surfaces / Qin, Jie in Journal of hydraulic research, Vol. 49 N° 3 (Mai/Juin 2011) 

Public ISBD [article]  in Journal of hydraulic research > Vol. 49 N° 3 (Mai/Juin 2011) . - pp.345-351 Titre : Multifractal characterization of water-worked gravel surfaces Type de document : texte imprimé Auteurs : Qin, Jie, Auteur ; Sai Leung Ng, Auteur Année de publication : 2011 Article en page(s) : pp.345-351 Note générale : Hydraulique Langues : Anglais (eng) Mots-clés : Armouring  process  Digital  elevation  model  Gravel  surface  Multifractal  analysis  Roughness Index. décimale : 627 Ingénierie des cours d'eau naturels, des ports, des rades et des cotes. Installations de navigation, de dragage, de récupération et de sauvetage. Barrages et centrales électriques hydrauliques Résumé : This study investigates the roughness of water-worked gravel surfaces using stable gravel-beds armoured in flume and field experiments. As an alternative to traditional approaches, multifractal analysis is employed to investigate the roughness of these surfaces. Power spectra analysis is used to study scale-invariant regimes, defined by the ranges of scales where the spectra follow power laws. Then, multifractal spectra are calculated and analysed. The strength of multifractality reflecting heterogeneity of elevations is related to the development of a stable armour layer. The development of armouring processes of the gravel surfaces formed in the flume experiments is investigated using the effective grain size approach based on Gessler's model. For surfaces in the field, the two-dimensional second-order structure function is used to study the static armour surfaces due to the absence of historical hydrological data. The results of these analyses confirm the results of multifractal analyses. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.567762 [article] Multifractal characterization of water-worked gravel surfaces [texte imprimé] / Qin, Jie, Auteur ; Sai Leung Ng, Auteur . - 2011 . - pp.345-351. Hydraulique Langues : Anglais (eng) in Journal of hydraulic research > Vol. 49 N° 3 (Mai/Juin 2011) . - pp.345-351 Mots-clés : Armouring  process  Digital  elevation  model  Gravel  surface  Multifractal  analysis  Roughness Index. décimale : 627 Ingénierie des cours d'eau naturels, des ports, des rades et des cotes. Installations de navigation, de dragage, de récupération et de sauvetage. Barrages et centrales électriques hydrauliques Résumé : This study investigates the roughness of water-worked gravel surfaces using stable gravel-beds armoured in flume and field experiments. As an alternative to traditional approaches, multifractal analysis is employed to investigate the roughness of these surfaces. Power spectra analysis is used to study scale-invariant regimes, defined by the ranges of scales where the spectra follow power laws. Then, multifractal spectra are calculated and analysed. The strength of multifractality reflecting heterogeneity of elevations is related to the development of a stable armour layer. The development of armouring processes of the gravel surfaces formed in the flume experiments is investigated using the effective grain size approach based on Gessler's model. For surfaces in the field, the two-dimensional second-order structure function is used to study the static armour surfaces due to the absence of historical hydrological data. The results of these analyses confirm the results of multifractal analyses. DEWEY : 627 ISSN : 0022-1686 En ligne : http://www.tandfonline.com/doi/abs/10.1080/00221686.2011.567762