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Classifying physiographic regimes on terrain and hydrologic factors for adaptive generalization of stream networks / Lauwrence V. Stanislawski in International journal of cartography, Vol 6 n° 1 (March 2020)
[article]
Titre : Classifying physiographic regimes on terrain and hydrologic factors for adaptive generalization of stream networks Type de document : Article/Communication Auteurs : Lauwrence V. Stanislawski, Auteur ; Michael P. Finn, Auteur ; Barbara P. Buttenfield, Auteur Année de publication : 2020 Article en page(s) : pp 4 - 21 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] algorithme de généralisation
[Termes IGN] altitude
[Termes IGN] base de données hydrographiques
[Termes IGN] cartographie des flux
[Termes IGN] classification dirigée
[Termes IGN] classification par maximum de vraisemblance
[Termes IGN] cours d'eau
[Termes IGN] drainage
[Termes IGN] Etats-Unis
[Termes IGN] pente
[Termes IGN] perméabilité du sol
[Termes IGN] représentation multiple
[Termes IGN] réseau hydrographique
[Termes IGN] ruissellement
[Termes IGN] segmentation
[Termes IGN] traitement automatique de données
[Vedettes matières IGN] GénéralisationRésumé : (auteur) Automated generalization software must accommodate multi-scale representations of hydrographic networks across a variety of geographic landscapes, because scale-related hydrography differences are known to vary in different physical conditions. While generalization algorithms have been tailored to specific regions and landscape conditions by several researchers in recent years, the selection and characterization of regional conditions have not been formally defined nor statistically validated. This paper undertakes a systematic classification of landscape types in the conterminous United States to spatially subset the country into workable units, in preparation for systematic tailoring of generalization workflows that preserve hydrographic characteristics. The classification is based upon elevation, standard deviation of elevation, slope, runoff, drainage and bedrock density, soil and bedrock permeability, area of inland surface water, infiltration-excess of overland flow, and a base flow index. A seven class solution shows low misclassification rates except in areas of high landscape diversity such as the Appalachians, Rocky Mountains, and Western coastal regions. Numéro de notice : A2020-070 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/23729333.2018.1443759 Date de publication en ligne : 20/03/2018 En ligne : https://doi.org/10.1080/23729333.2018.1443759 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94632
in International journal of cartography > Vol 6 n° 1 (March 2020) . - pp 4 - 21[article]Les États-Unis remplacent le NAD83 par le NATRF2022 : ce que cela signifie pour le Canada / Caroline Erickson in Geomatica, vol 74 n° 1 (Mars 2020)
[article]
Titre : Les États-Unis remplacent le NAD83 par le NATRF2022 : ce que cela signifie pour le Canada Type de document : Article/Communication Auteurs : Caroline Erickson, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 1 - 8 Note générale : bibliographie Langues : Anglais (eng) Français (fre) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] Canada
[Termes IGN] Etats-Unis
[Termes IGN] North American Datum 1983
[Termes IGN] North American Terrestrial Reference Frame 2022Résumé : (auteur) En 2022, les États-Unis, dans le cadre de la modernisation de leur système de référence, remplaceront le Système de référence géodésique nord-américain de 1983 (NAD83) par un nouveau cadre de référence terrestre nord-américain (NATRF2022), ce qui entraînera des différences de coordonnées horizontales de 1,3 à 1,5 mètre à la frontière canado-américaine par rapport au NAD83 (SCRS) canadien. Jamais auparavant des différences aussi importantes n’avaient existé entre les cadres de référence de nos deux pays. Le présent document examine les raisons pour lesquelles les États-Unis apportent ce changement et examine ensuite la situation du Canada en ce qui concerne les cadres de référence. Il y a des raisons impérieuses pour que le Canada emboîte le pas et passe au NATRF2022 d’ici une décennie, mais cela représente aussi des défis majeurs. Que le Canada suive ou non la même voie, il y a beaucoup de travail à accomplir pour préparer le Canada à l’adoption du NATRF2022 par les États-Unis. Le présent document se veut une première étape pour informer la communauté géospatiale canadienne de la décision des États-Unis d’adopter le NATRF2022 et de ce que cela signifie pour le Canada. Numéro de notice : A2020-841 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1139/geomat-2020-0008 En ligne : https://doi.org/10.1139/geomat-2020-0008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98318
in Geomatica > vol 74 n° 1 (Mars 2020) . - pp 1 - 8[article]Improving operational radar rainfall estimates using profiler observations over complex terrain in Northern California / Haonan Chen in IEEE Transactions on geoscience and remote sensing, vol 58 n° 3 (March 2020)
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Titre : Improving operational radar rainfall estimates using profiler observations over complex terrain in Northern California Type de document : Article/Communication Auteurs : Haonan Chen, Auteur ; Robert Cifelli, Auteur ; Allen White, Auteur Année de publication : 2020 Article en page(s) : pp 1821 - 1832 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] Californie (Etats-Unis)
[Termes IGN] correction d'image
[Termes IGN] données radar
[Termes IGN] erreur d'approximation
[Termes IGN] faisceau
[Termes IGN] montagne
[Termes IGN] orographie
[Termes IGN] précipitation
[Termes IGN] prévision météorologique
[Termes IGN] télédétection en hyperfréquence
[Termes IGN] télédétection réflective
[Termes IGN] visée verticaleRésumé : (Auteur) Quantitative precipitation estimation (QPE) using operational weather radars in the western United States is still a challenging issue due to the beam blockage in the mountainous areas and complex rainfall microphysics induced by the orographic enhancement. This article aims to improve operational radar rainfall estimates in complex terrain by incorporating auxiliary remote sensing observations. An innovative vertical profile of reflectivity (VPR) correction scheme is developed for operational radar using observations from multiple vertically pointing profilers to represent the vertical structure of precipitation at various locations. A demonstration study in the Russian River basin in Northern California is detailed. Results show that the QPE performance is significantly improved after VPR correction, and this new VPR correction approach is superior to the conventional approach currently applied in the operational radar rainfall system. The normalized standard error of hourly rainfall estimates for the two precipitation events presented in this article is improved by ~20% after applying the proposed VPR correction scheme. Numéro de notice : A2020-090 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2019.2949214 Date de publication en ligne : 12/11/2019 En ligne : https://doi.org/10.1109/TGRS.2019.2949214 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94664
in IEEE Transactions on geoscience and remote sensing > vol 58 n° 3 (March 2020) . - pp 1821 - 1832[article]Road network structure and ride-sharing accessibility: A network science perspective / Mingshu Wang in Computers, Environment and Urban Systems, vol 80 (March 2020)
[article]
Titre : Road network structure and ride-sharing accessibility: A network science perspective Type de document : Article/Communication Auteurs : Mingshu Wang, Auteur ; Zheyan Chen, Auteur ; Lan Mu, Auteur ; et al., Auteur Année de publication : 2020 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] Atlanta (Géorgie)
[Termes IGN] autopartage
[Termes IGN] densité de population
[Termes IGN] gestion urbaine
[Termes IGN] migration pendulaire
[Termes IGN] modèle conceptuel de données localisées
[Termes IGN] OpenStreetMap
[Termes IGN] réseau routier
[Termes IGN] système d'information géographiqueRésumé : (auteur) The prosperity of ride-sharing services has rippled in the communities of GIScience, transportation, and urban planning. Meanwhile, road network structure has been analyzed from a network science perspective that focuses on nodes and relational links and aims to predictive models. However, limited empirical studies have explored the relationship between road network structure and ride-sharing accessibility through such perspective. This paper utilizes the spatial Durbin model to understand the relationship between road network structure and ride-sharing accessibility, proxied by Uber accessibility, through classical network measures of degree, closeness, and betweenness centrality. Taking the city of Atlanta as a case study, we have found in addition to population density and road network density, larger values of degree centrality and smaller values of closeness centrality of the road network are associated with better accessibility of Uber services. However, the effects of betweenness centrality are not significant. Furthermore, we have revealed heterogeneous effects of degree centrality and closeness centrality on the accessibility of Uber services, as the magnitudes of their effects vary by different time windows (i.e., weekday vs. weekend, rush hour in the morning vs. evening). Network science provides us both conceptual and methodological measures to understand the association between road network structure and ride-sharing accessibility. In this study, we constructed road network structure measures with OpenStreetMap, which is reproducible, replicable, and scalable because of its global coverage and public availability. The study resonates with the notion of cities as the set of interactions across networks, as we have observed time-sensitive heterogeneous effects of road network structure on ride-sharing accessibility. Numéro de notice : A2020-190 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1016/j.compenvurbsys.2019.101430 Date de publication en ligne : 12/11/2019 En ligne : https://doi.org/10.1016/j.compenvurbsys.2019.101430 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94852
in Computers, Environment and Urban Systems > vol 80 (March 2020)[article]Uber movement data: a proxy for average one-way commuting times by car / Yeran Sun in ISPRS International journal of geo-information, vol 9 n° 3 (March 2020)
[article]
Titre : Uber movement data: a proxy for average one-way commuting times by car Type de document : Article/Communication Auteurs : Yeran Sun, Auteur ; Yinming Ren, Auteur ; Xuan Sun, Auteur Année de publication : 2020 Article en page(s) : 16 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] Boston (Massachusetts)
[Termes IGN] distribution spatiale
[Termes IGN] durée de trajet
[Termes IGN] flux
[Termes IGN] migration pendulaire
[Termes IGN] objet mobile
[Termes IGN] origine - destination
[Termes IGN] planification urbaine
[Termes IGN] taxi
[Termes IGN] trace GPSRésumé : (auteur) Recently, Uber released datasets named Uber Movement to the public in support of urban planning and transportation planning. To prevent user privacy issues, Uber aggregates car GPS traces into small areas. After aggregating car GPS traces into small areas, Uber releases free data products that indicate the average travel times of Uber cars between two small areas. The average travel times of Uber cars in the morning peak time periods on weekdays could be used as a proxy for average one-way car-based commuting times. In this study, to demonstrate usefulness of Uber Movement data, we use Uber Movement data as a proxy for commuting time data by which commuters’ average one-way commuting time across Greater Boston can be figured out. We propose a new approach to estimate the average car-based commuting times through combining commuting times from Uber Movement data and commuting flows from travel survey data. To further demonstrate the applicability of the commuting times estimated by Uber movement data, this study further measures the spatial accessibility of jobs by car by aggregating place-to-place commuting times to census tracts. The empirical results further uncover that 1) commuters’ average one-way commuting time is around 20 min across Greater Boston; 2) more than 75% of car-based commuters are likely to have a one-way commuting time of less than 30 min; 3) less than 1% of car-based commuters are likely to have a one-way commuting time of more than 60 min; and 4) the areas suffering a lower level of spatial accessibility of jobs by car are likely to be evenly distributed across Greater Boston. Numéro de notice : A2020-255 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/ijgi9030184 Date de publication en ligne : 24/03/2020 En ligne : https://doi.org/10.3390/ijgi9030184 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95010
in ISPRS International journal of geo-information > vol 9 n° 3 (March 2020) . - 16 p.[article]Assessing public transit performance using real-time data: spatiotemporal patterns of bus operation delays in Columbus, Ohio, USA / Yongha Park in International journal of geographical information science IJGIS, vol 34 n° 2 (February 2020)PermalinkA LiDAR–optical data fusion approach for identifying and measuring small stream impoundments and dams / Benjamin Swan in Transactions in GIS, Vol 24 n° 1 (February 2020)PermalinkSimilarity measurement on human mobility data with spatially weighted structural similarity index (SpSSIM) / Chanwoo Jin in Transactions in GIS, Vol 24 n° 1 (February 2020)PermalinkVolcano-seismic transfer learning and uncertainty quantification with bayesian neural networks / Angel Bueno in IEEE Transactions on geoscience and remote sensing, vol 58 n° 2 (February 2020)PermalinkComparison of multi-seasonal Landsat 8, Sentinel-2 and hyperspectral images for mapping forest alliances in Northern California / Matthew L. Clark in ISPRS Journal of photogrammetry and remote sensing, vol 159 (January 2020)PermalinkDe l’image optique "multi-stéréo" à la topographie très haute résolution et la cartographie automatique des failles par apprentissage profond / Lionel Matteo (2020)PermalinkOptimizing arbovirus surveillance using risk mapping and coverage modelling / Joni A. Downs in Annals of GIS, Vol 26 n° 1 (January 2020)PermalinkRadar interferometry of unstable slopes / Theeba Raveendran (2020)PermalinkSubsidence is determined in the heart of the Central Valley using Post Processed Static and Precise Point Positioning techniques / Y. Facio in Journal of applied geodesy, vol 14 n° 1 (January 2020)PermalinkA systematic evaluation of influence of image selection process on remote sensing-based burn severity indices in North American boreal forest and tundra ecosystems / Dong Chen in ISPRS Journal of photogrammetry and remote sensing, vol 159 (January 2020)Permalink