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Impact of beam diameter and scanning approach on point cloud quality of terrestrial laser scanning in forests / Meinrad Abegg in IEEE Transactions on geoscience and remote sensing, vol 59 n° 10 (October 2021)
[article]
Titre : Impact of beam diameter and scanning approach on point cloud quality of terrestrial laser scanning in forests Type de document : Article/Communication Auteurs : Meinrad Abegg, Auteur ; Ruedi Boesch, Auteur ; Michael E. Schaepman, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 8153 - 8167 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] densité du peuplement
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] faisceau laser
[Termes IGN] forêt
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] modélisation de la forêt
[Termes IGN] qualité des données
[Termes IGN] semis de points
[Termes IGN] signal lidar
[Termes IGN] Suisse
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) In recent years, portable laser scanning devices and their applications in the context of forest mensuration have undergone rapid methodological and technological developments. Devices have become smaller, lighter, and more affordable, whereas new data-driven methods and software packages have facilitated the derivation of information from point clouds. Thus, terrestrial laser scanning (TLS) is now well established, and laser–object interactions have been studied using theoretical, modeling, and experimental approaches. The representation of scanned objects in terms of accuracy and completeness is a key factor for successful feature extraction. Still, little is known about the influence of TLS and survey properties on point clouds in complex scattering environments, such as forests. In this study, we investigate the influence of laser beam diameter and signal triggering on the quality of point clouds in forested environments. Based on the Swiss National Forest Inventory data, we simulate the TLS measurements in 684 virtual forest stands using a 3-D content creation suite. We show that small objects lack sufficient representation in the point cloud and they are further negatively influenced by large laser beam diameters, dense stands, and large distances from the scanning device. We provide simulations that make it possible to derive a rationale for decisions regarding the appropriate choice of TLS device and survey configuration for forest inventories. Numéro de notice : A2021-709 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1109/TGRS.2020.3037763 Date de publication en ligne : 08/12/2020 En ligne : https://doi.org/10.1109/TGRS.2020.3037763 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98608
in IEEE Transactions on geoscience and remote sensing > vol 59 n° 10 (October 2021) . - pp 8153 - 8167[article]Impact of travel time uncertainties on modeling of spatial accessibility: a comparison of street data sources / Yan Lin in Cartography and Geographic Information Science, vol 48 n° 6 (October 2021)
[article]
Titre : Impact of travel time uncertainties on modeling of spatial accessibility: a comparison of street data sources Type de document : Article/Communication Auteurs : Yan Lin, Auteur ; Christopher Lippitt, Auteur ; Daniel Beene, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 471 - 490 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] accessibilité
[Termes IGN] analyse de sensibilité
[Termes IGN] ArcMap
[Termes IGN] données localisées des bénévoles
[Termes IGN] durée de trajet
[Termes IGN] Google Maps
[Termes IGN] incertitude des données
[Termes IGN] indexation spatiale
[Termes IGN] navigation automobile
[Termes IGN] Nouveau-Mexique (Etats-Unis)
[Termes IGN] OpenStreetMap
[Termes IGN] plan de déplacement urbain
[Termes IGN] réseau routier
[Termes IGN] système d'information géographique
[Termes IGN] transport publicRésumé : (auteur) GIS-based spatial access measures have been used extensively to monitor social equity and to help develop policy. However, inherent uncertainties in the road datasets used in spatial access estimates remain largely underreported. These uncertainties might result in unrecognized biases within visualization products and decision-making outcomes that strive to improve social equity based on seemingly egalitarian accessibility metrics. To better understand and address these uncertainties, we evaluated variations in travel impedance for car and bus transportation using proprietary, volunteer-information-based, and free (non-volunteer-information-based) street networks. We then interpreted the measured variations through the lens of street data uncertainty and its propagation in a common E2SFCA model of spatial accessibility. Results indicated that travel impedance disagreement propagates through the modeling process to effect agreement of spatial access index (SPAI) estimates among different street sources, with larger uncertainties observed for bus travel than car travel. Higher impedance coefficients (β), a model parameter, reduced the impact of street-source variations on estimates. Less urbanized regions were found to experience higher street-source variations when compared with the core-metropolitan area. We also demonstrated that a relative spatial access measure – the spatial access ratio (SPAR) – reduced uncertainties introduced by the choice of street datasets. Careful selection of reliable street sources and model parameters (e.g. higher β), as well as consideration of the potential for bias, particularly for less urbanized areas and areas reliant on public transportation, is warranted when leveraging SPAI to inform policy. When reliable/accurate road network data are not accessible or data quality information is not available, the SPAR is a suitable alternative or supplement to SPAI for visualization and analyses. Numéro de notice : A2021-712 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/15230406.2021.1960609 Date de publication en ligne : 01/09/2021 En ligne : https://doi.org/10.1080/15230406.2021.1960609 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98617
in Cartography and Geographic Information Science > vol 48 n° 6 (October 2021) . - pp 471 - 490[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 032-2021061 RAB Revue Centre de documentation En réserve L003 Disponible Loosening the grid: topology as the basis for a more inclusive GIS / L. Westerveld in International journal of geographical information science IJGIS, vol 35 n° 10 (October 2021)
[article]
Titre : Loosening the grid: topology as the basis for a more inclusive GIS Type de document : Article/Communication Auteurs : L. Westerveld, Auteur ; A.K. Knowles, Auteur Année de publication : 2021 Article en page(s) : pp 2108 - 2127 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] analyse spatiale
[Termes IGN] cartographie historique
[Termes IGN] données spatiotemporelles
[Termes IGN] Europe de l'est
[Termes IGN] graphe topologique
[Termes IGN] guerre
[Termes IGN] histoire
[Termes IGN] historique des données
[Termes IGN] relation topologiqueRésumé : (auteur) The past 25 years have seen a proliferation of interest in GIS among humanists and humanistic social scientists. Under various banners – historical GIS, qualitative and mixed methods GIS, spatial and digital history, digital humanities, spatial humanities or geohumanities – researchers have developed new ways to include qualitative data within the framework of GIS. At the same time, social and theoretical critiques of GIS as a tool wielded chiefly by and for those in power have increased awareness of its limitations, particularly for studying human perceptions, experiences, and the meanings of place. We agree with a growing chorus of geographers that the most common data structures in GIS are inadequate to capture or analyze the relational dimensions of subjectivity. As part of the solution, we propose an alternative hybrid framework that prioritizes topological relationships while retaining coordinate locations as points of connection between geographic places and experiential evidence. This article explains how the challenges posed by Holocaust survivor testimony inspired us to pursue inductive spatial analysis and non-coordinate means of mapping. We then set out a model for a topological GIS and illustrate its application with two survivor testimonies and a map of their experiences. Numéro de notice : A2021-680 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2020.1856854 Date de publication en ligne : 07/12/2020 En ligne : https://doi.org/10.1080/13658816.2020.1856854 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98399
in International journal of geographical information science IJGIS > vol 35 n° 10 (October 2021) . - pp 2108 - 2127[article]Quantifying historical landscape change with repeat photography: an accuracy assessment of geospatial data obtained through monoplotting / Ulrike Bayr in International journal of geographical information science IJGIS, vol 35 n° 10 (October 2021)
[article]
Titre : Quantifying historical landscape change with repeat photography: an accuracy assessment of geospatial data obtained through monoplotting Type de document : Article/Communication Auteurs : Ulrike Bayr, Auteur Année de publication : 2021 Article en page(s) : pp 2026 - 2046 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] analyse diachronique
[Termes IGN] analyse du paysage
[Termes IGN] angle d'incidence
[Termes IGN] détection de changement
[Termes IGN] données anciennes
[Termes IGN] données multitemporelles
[Termes IGN] image oblique
[Termes IGN] modèle numérique de terrain
[Termes IGN] monorestitution
[Termes IGN] Norvège
[Termes IGN] orthoimage géoréférencée
[Termes IGN] photographie aérienne
[Termes IGN] photographie terrestre
[Termes IGN] point d'appui
[Termes IGN] précision des donnéesRésumé : (auteur) Traditional landscape photographs reaching back until the second half of the nineteenth century represent a valuable image source for the study of long-term landscape change. Due to the oblique perspective and the lack of geographical reference, landscape photographs are hardly used for quantitative research. In this study, oblique landscape photographs from the Norwegian landscape monitoring program are georeferenced using the WSL Monoplotting Tool with the aim of evaluating the accuracy of point and polygon features. In addition, the study shows how the resolution of the chosen digital terrain model and other factors affect accuracy. Points mapped on the landscape photograph had a mean displacement of 1.52 m from their location on a corresponding aerial photograph, while mapped areas deviated on average 5.6% in size. The resolution of the DTM, the placement of GCPs and the angle of incidence were identified as relevant factors to achieve accurate geospatial data. An example on forest expansion at the abandoned mountain farm Flysetra in Mid-Norway demonstrates how repeat photography facilitates the georectification process in the absence of reliable ground control points (GCPs) in very old photographs. Numéro de notice : A2021-656 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2021.1871910 Date de publication en ligne : 20/01/2021 En ligne : https://doi.org/10.1080/13658816.2021.1871910 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98392
in International journal of geographical information science IJGIS > vol 35 n° 10 (October 2021) . - pp 2026 - 2046[article]Urban geomorphology of a historical city straddling the Tanaro River (Alessandria, NW Italy) / Andrea Mandarino in Journal of maps, vol 17 n° 4 (October 2021)
[article]
Titre : Urban geomorphology of a historical city straddling the Tanaro River (Alessandria, NW Italy) Type de document : Article/Communication Auteurs : Andrea Mandarino, Auteur ; Fabio Luino, Auteur ; Laura Turconi, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 29 - 41 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse diachronique
[Termes IGN] carte ancienne
[Termes IGN] carte géomorphologique
[Termes IGN] cartographie historique
[Termes IGN] étalement urbain
[Termes IGN] géomorphologie locale
[Termes IGN] historique des données
[Termes IGN] paysage urbain
[Termes IGN] Piémont (Italie)
[Termes IGN] planification urbaine
[Termes IGN] Pô (plaine)
[Termes IGN] système d'information géographiqueRésumé : (auteur) The integration of field surveys, bibliographic research and multitemporal analysis of historical maps, aerial photographs and satellite images in a GIS environment, allowed the current and past geomorphological features of the old city of Alessandria and its surrounding areas, NW Italy, to be identified and mapped. Their analysis provided an overview of the geomorphological evolution of the city that is strictly related to the historical vicissitudes occurred since the Middle Ages. Nowadays, the most representative landforms and deposits characterizing the urban landscape result from human interventions and are associated with ancient military facilities and infrastructures, a historical man-made channel network no longer recognizable, the Tanaro riverbed channelization, and the urban sprawl occurred from the second half of the nineteenth century onwards. This study represents a useful tool for urban planning and management and for raising the citizens’ awareness of the urban-landscape geomorphological features and evolution, and therefore the geo-hydrological risk. Numéro de notice : A2021-923 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/17445647.2020.1746420 Date de publication en ligne : 29/03/2020 En ligne : https://doi.org/10.1080/17445647.2020.1746420 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99280
in Journal of maps > vol 17 n° 4 (October 2021) . - pp 29 - 41[article]Aerial and UAV images for photogrammetric analysis of Belvedere Glacier evolution in the period 1977–2019 / Carlo Lapige De Gaetani in Remote sensing, vol 13 n° 18 (September-2 2021)PermalinkBenford’s law and geographical information – the example of OpenStreetMap / Franz-Benjamin Mocnik in International journal of geographical information science IJGIS, vol 35 n° 9 (September 2021)PermalinkThe willingness of volonteers to report changes on topographic maps / Mihaela Triglav Cekada in Geodetski vestnik, vol 65 n° 3 (September - November 2021)PermalinkVisualization of GNSS multipath effects and its potential application in IGS data processing / Weiming Tang in Journal of geodesy, vol 95 n° 9 (September 2021)PermalinkQuantifying coherence between TDM90, SRTM90 and ASTER90 / Umut Gunes Sefercik in Geocarto international, vol 36 n° 15 ([15/08/2021])PermalinkApplication of GIS tools in the measurement analysis of urban spatial layouts using the square grid method / Łukasz Musiaka in ISPRS International journal of geo-information, vol 10 n° 8 (August 2021)PermalinkDigital building-height preparation from satellite stereo images / P.S. Prakash in Photogrammetric Engineering & Remote Sensing, PERS, vol 87 n° 8 (August 2021)PermalinkThe potential impact of hydrodynamic leveling on the quality of the European vertical reference frame / Yosra Afrasteh in Journal of geodesy, vol 95 n° 8 (August 2021)PermalinkDeformation analysis of a reference wall towards the uncertainty investigation of terrestrial laser scanners / Berit Schmitz in Journal of applied geodesy, vol 15 n° 3 (July 2021)PermalinkA multi-layer perceptron neural network to mitigate the interference of time synchronization attacks in stationary GPS receivers / N. Orouji in GPS solutions, vol 25 n° 3 (July 2021)Permalink