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Geospatial analysis of land-use change processes in a densely populated coastal city: the case of Port Harcourt, south-east Nigeria / Glory O. Enaruvbe in Geocarto international, vol 30 n° 3 - 4 (March - April 2015)
[article]
Titre : Geospatial analysis of land-use change processes in a densely populated coastal city: the case of Port Harcourt, south-east Nigeria Type de document : Article/Communication Auteurs : Glory O. Enaruvbe, Auteur ; Olusola Ige-Olumide, Auteur Année de publication : 2015 Article en page(s) : pp 441 - 456 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse diachronique
[Termes IGN] changement d'occupation du sol
[Termes IGN] détection de changement
[Termes IGN] écosystème
[Termes IGN] image Landsat
[Termes IGN] littoral
[Termes IGN] mangrove
[Termes IGN] Nigéria
[Termes IGN] occupation du sol
[Termes IGN] utilisation du solRésumé : (Auteur) This study examines the pattern and processes of land-use change in a densely populated coastal city in the oil-rich Niger Delta region of Nigeria for 27 years using remote sensing and Geographic Information Systems. The results indicate that between 1986 and 2013, settlement/bare surface, mangrove forest/wetland and water body increased at 0.84% per year, 0.05% per year and 0.10% per year, respectively, while arable land/secondary vegetation and natural forest loss at 0.47% per year and 0.52% per year, respectively. This implies that intensity of change varies temporally. The implications of these changes include loss of valuable environmental goods and services, alteration of the food chain and increased impacts of climate change–related disasters. It is recommended that steps be taken to slow down the rate of land-use change in the study area to reduce its impact on the environment and social well-being. Numéro de notice : A2015-305 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2014.883435 Date de publication en ligne : 14/02/2014 En ligne : https://doi.org/10.1080/10106049.2014.883435 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76523
in Geocarto international > vol 30 n° 3 - 4 (March - April 2015) . - pp 441 - 456[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 059-2015021 RAB Revue Centre de documentation En réserve L003 Disponible Pour une représentation dynamique des formations à silex . Partie 2 : Analyse et représentation de la diffusion des silex / Denis Dalphinet in Géomatique expert, n° 103 (mars - avril 2015)
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Titre : Pour une représentation dynamique des formations à silex . Partie 2 : Analyse et représentation de la diffusion des silex Type de document : Article/Communication Auteurs : Denis Dalphinet, Auteur Année de publication : 2015 Article en page(s) : pp 24 - 38 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] BD Carthage
[Termes IGN] carte thématique
[Termes IGN] réseau hydrographique
[Termes IGN] Rhône, delta du
[Termes IGN] système d'information géographique
[Termes IGN] Vaucluse (84)
[Termes IGN] Ventoux, MontRésumé : (Auteur) [Introduction] L'enjeu de ce travail est de cartographier la diffusion théorique des silex de leur lieux de formation aux différentes zones secondaires où ils se déposent par l'action de phénomènes de transport. Le principal vecteur de ce déplacement est le réseau hydrographique. Les silex sont trasportés sur des kilomètres depuis les lieux de formation à travers les cours d'eau, parfois jusqu'aux exutoires finaux (dans ce cas d'étude, principalement le delta du Rhône). Ce projet sera axé sur le réseau hydrographique des cinq départements où les zones de formation à silex ont été numérisées : Alpes-de-Haute-provence (04), Bouches-du-Rhône (13), Drôme (26), Var (83) et Vaucluse (84). Numéro de notice : A2015-127 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75784
in Géomatique expert > n° 103 (mars - avril 2015) . - pp 24 - 38[article]ContenuExemplaires(2)
Code-barres Cote Support Localisation Section Disponibilité 265-2015021 RAB Revue Centre de documentation En réserve L003 Disponible IFN-001-P001689 GEO Revue Nogent-sur-Vernisson Salle périodiques Disponible Density-based clustering for data containing two types of points / Tao Pei in International journal of geographical information science IJGIS, vol 29 n° 2 (February 2015)
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Titre : Density-based clustering for data containing two types of points Type de document : Article/Communication Auteurs : Tao Pei, Auteur ; Weiyi Wang, Auteur ; Hengcai Zhang, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 175 - 193 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse en composantes indépendantes
[Termes IGN] classification par seuillage sur la limite la plus proche
[Termes IGN] densité d'information
[Termes IGN] échelle d'intensité
[Termes IGN] groupe
[Termes IGN] taxi
[Termes IGN] transport routierRésumé : (Auteur) When only one type of point is distributed in a region, clustered points can be seen as an anomaly. When two different types of points coexist in a region, they overlap at different places with various densities. In such cases, the meaning of a cluster of one type of point may be altered if points of the other type show different densities within the same cluster. If we consider the origins and destinations (OD) of taxicab trips, the clustering of both in the morning may indicate a transportation hub, whereas clustered origins and sparse destinations (a hot spot where taxis are in short supply) could suggest a densely populated residential area. This cannot be identified by previous clustering methods, so it is worthwhile studying a clustering method for two types of points. The concept of two-component clustering is first defined in this paper as a group containing two types of points, at least one of which exhibits clustering. We then propose a density-based method for identifying two-component clusters. The method is divided into four steps. The first estimates the clustering scale of the point data. The second transforms the point data into the 2D density domain, where the x and y axes represent the local density of each type of point around each point, respectively. The third determines the thresholds for extracting the clusters, and the fourth generates two-component clusters using a density-connectivity mechanism. The method is applied to taxicab trip data in Beijing. Three types of two-component clusters are identified: high-density origins and destinations, high-density origins and low-density destinations, and low-density origins and high-density destinations. The clustering results are verified by the spatial relationship between the cluster locations and their land-use types over different periods of the day. Numéro de notice : A2015-577 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2014.955027 En ligne : http://www.tandfonline.com/doi/full/10.1080/13658816.2014.955027 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77839
in International journal of geographical information science IJGIS > vol 29 n° 2 (February 2015) . - pp 175 - 193[article]Geo-located community detection in Twitter with enhanced fast-greedy optimization of modularity: the case study of typhoon Haiyan / Mohamed Bakillah in International journal of geographical information science IJGIS, vol 29 n° 2 (February 2015)
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Titre : Geo-located community detection in Twitter with enhanced fast-greedy optimization of modularity: the case study of typhoon Haiyan Type de document : Article/Communication Auteurs : Mohamed Bakillah, Auteur ; Ren-Yu Li, Auteur ; Steve H.L. Liang, Auteur Année de publication : 2015 Article en page(s) : pp 258 - 279 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] communauté virtuelle
[Termes IGN] données issues des réseaux sociaux
[Termes IGN] exploration de données géographiques
[Termes IGN] géopositionnement
[Termes IGN] risque naturel
[Termes IGN] TwitterRésumé : (Auteur) As they increase in popularity, social media are regarded as important sources of information on geographical phenomena. Studies have also shown that people rely on social media to communicate during disasters and emergency situation, and that the exchanged messages can be used to get an insight into the situation. Spatial data mining techniques are one way to extract relevant information from social media. In this article, our aim is to contribute to this field by investigating how graph clustering can be applied to support the detection of geo-located communities in Twitter in disaster situations. For this purpose, we have enhanced the fast-greedy optimization of modularity (FGM) clustering algorithm with semantic similarity so that it can deal with the complex social graphs extracted from Twitter. Then, we have coupled the enhanced FGM with the varied density-based spatial clustering of applications with noise spatial clustering algorithm to obtain spatial clusters at different temporal snapshots. The method was experimented with a case study on typhoon Haiyan in the Philippines, and Twitter’s different interaction modes were compared to create the graph of users and to detect communities. The experiments show that communities that are relevant to identify areas where disaster-related incidents were reported can be extracted, and that the enhanced algorithm outperforms the generic one in this task. Numéro de notice : A2015-579 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2014.964247 En ligne : http://www.tandfonline.com/doi/full/10.1080/13658816.2014.964247 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77841
in International journal of geographical information science IJGIS > vol 29 n° 2 (February 2015) . - pp 258 - 279[article]Analysis of spatial variability of near-surface soil moisture to increase rainfall-runoff modelling accuracy in SW Hungary / P. Hegedüs in Open geosciences, vol 7 n° 1 (January 2015)
[article]
Titre : Analysis of spatial variability of near-surface soil moisture to increase rainfall-runoff modelling accuracy in SW Hungary Type de document : Article/Communication Auteurs : P. Hegedüs, Auteur ; S. Czigány, Auteur ; E. Pirkhoffer, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 126 - 139 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] données localisées
[Termes IGN] Hongrie
[Termes IGN] humidité du sol
[Termes IGN] interpolation spatiale
[Termes IGN] modèle numérique
[Termes IGN] ruissellement
[Termes IGN] série temporelle
[Termes IGN] valléeRésumé : (auteur) Between September 5, 2008 and September 5, 2009, near-surface soil moisture time series were collected in the northern part of a 1.7 km2 watershed in SWHungary at 14 monitoring locations using a portable TDR-300 soil moisture sensor. The objectives of this study are to increase the accuracy of soil moisture measurement at watershed scale, to improve flood forecasting accuracy, and to optimize soil moisture sensor density.
According to our results, in 10 of 13 cases, a strong correlation exists between the measured soil moisture data of Station 5 and all other monitoring stations; Station 5 is considered representative for the entire watershed. Logically, the selection of the location of the representative measurement point(s) is essential for obtaining representative and accurate soil moisture values for the given watershed. This could be done by (i) employing monitoring stations of higher number at the exploratory phase of the monitoring, (ii) mapping soil physical properties at watershed scale, and (iii) running cross-relational statistical analyses on the obtained data.
Our findings indicate that increasing the number of soil moisture data points available for interpolation increases the accuracy of watershed-scale soil moisture estimation. The data set used for interpolation (and estimation of mean antecedent soil moisture values) could be improved (thus, having a higher number of data points) by selecting points of similar properties to the measurement points from the DEM and soil databases. By using a higher number of data points for interpolation, both interpolation accuracy and spatial resolution have increased for the measured soil moisture values for the Pósa Valley.Numéro de notice : A2015-438 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1515/geo-2015-0017 En ligne : https://doi.org/10.1515/geo-2015-0017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77038
in Open geosciences > vol 7 n° 1 (January 2015) . - pp 126 - 139[article]Bayesian belief networks as a versatile method for assessing uncertainty in land-change modeling / Carsten Krüger in International journal of geographical information science IJGIS, vol 29 n° 1 (January 2015)PermalinkÉvaluation des conséquences d’aménagements d’infrastructures sur les déplacements d’animaux : Définition et expérimentation d’un modèle de simulation agent / Laurence Jolivet in Cybergeo, European journal of geography, n° 2015 ([01/01/2015])PermalinkGeo-spatial modelling with unbalanced data: modelling the spatial pattern of human activity during the Stone Age / Jaroslav Jasiewicz in Open geosciences, vol 7 n° 1 (January 2015)PermalinkInvestigating the mobile phone data to estimate the origin destination flow and analysis, a case study: Paris region / Anahid Nabavi-Larijani in Transportation Research Procedia, vol 6 (2015)PermalinkPermalinkPermalinkA novel approach for generating routable road maps from vehicle GPS traces / Jing Wang in International journal of geographical information science IJGIS, vol 29 n° 1 (January 2015)PermalinkDetecting and analyzing mobility hotspots using surface networks / Y. Hu in Transactions in GIS, vol 18 n° 6 (December 2014)PermalinkModeling use of space from social media data using a biased random walker / Steven D. Prager in Transactions in GIS, vol 18 n° 6 (December 2014)PermalinkA new framework for solving the spatial network problems based on line graphs / Javad Saberian in Transactions in GIS, vol 18 n° 5 (October 2014)Permalink