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A new algebraic solution for transforming Cartesian to geodetic coordinates / Jia-Chun Guo in Survey review, vol 55 n° 389 (March 2023)
[article]
Titre : A new algebraic solution for transforming Cartesian to geodetic coordinates Type de document : Article/Communication Auteurs : Jia-Chun Guo, Auteur ; Wenbin Shen, Auteur Année de publication : 2023 Article en page(s) : pp 169 - 177 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] calcul algébrique
[Termes IGN] coordonnées cartésiennes
[Termes IGN] coordonnées géodésiques
[Termes IGN] système de coordonnées
[Termes IGN] transformation de coordonnéesRésumé : (auteur) An exact and stable algebraic solution based on solving a quartic equation with respect to the cosine function of the reduced latitude is proposed to transform Cartesian into geodetic coordinates. The unique proper root of the equation appropriate to the transformation is chosen from all possible roots by rigorous analyses and the singular region of the transformation that in which there at least one component of the geodetic coordinates is indeterminate or non-single-valued characteristics are determined strictly. The new algorithm does not need any approximation and the instability problems incurred in other algebraic solutions are overcome. For practical applications, the algorithm performs comparably to that of [Vermeille, H., 2011. An analytical method to transform geocentric into geodetic coordinates. Journal of geodesy, 85 (2), 105–117.] and shows a certain superiority in the singular disc over Vermeille's algorithm. Numéro de notice : A2023-135 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2022.2071055 Date de publication en ligne : 24/05/2022 En ligne : https://doi.org/10.1080/00396265.2022.2071055 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102686
in Survey review > vol 55 n° 389 (March 2023) . - pp 169 - 177[article]Effect of climate on cork-ring width and density of Quercus suber L. in Southern Portugal / Augusta Costa in Trees, vol 36 n° 6 (December 2022)
[article]
Titre : Effect of climate on cork-ring width and density of Quercus suber L. in Southern Portugal Type de document : Article/Communication Auteurs : Augusta Costa, Auteur ; José Graça, Auteur ; Inês Barbosa, Auteur Année de publication : 2022 Article en page(s) : pp 1711 - 1720 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse diachronique
[Termes IGN] anneau
[Termes IGN] climat méditerranéen
[Termes IGN] croissance des arbres
[Termes IGN] dendroécologie
[Termes IGN] Portugal
[Termes IGN] Quercus suber
[Termes IGN] volume en bois
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Cork rings have been extensively used in dendroecological studies of the Mediterranean evergreen cork oak (Quercus suber L.). Through measurements of cork-ring width only, strong relationships have been found between cork-ring widths and climate parameters. To our knowledge, cork-ring density, which is an important cork quality attribute, has never been used in any dendroecological study to explore physiological responses of the cork oak to climate change. In this study, we measured cork-ring width and density over 50 years (1962–2013), corresponding to five consecutive cork harvests, and analyzed their inter-annual fluctuations in eight trees from two different sites, a wetter peneplain area (Benavente) and a drier mountainous area (Grândola). Our results revealed a statistically significant correlation between cork-ring width and density (p Numéro de notice : A2022-915 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s00468-022-02321-0 Date de publication en ligne : 29/06/2022 En ligne : https://doi.org/10.1007/s00468-022-02321-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102351
in Trees > vol 36 n° 6 (December 2022) . - pp 1711 - 1720[article]Detection of suitable sites for rainwater harvesting planning in an arid region using geographic information system / Hadeel Qays Hashim in Applied geomatics, vol 13 n° 2 (June 2021)
[article]
Titre : Detection of suitable sites for rainwater harvesting planning in an arid region using geographic information system Type de document : Article/Communication Auteurs : Hadeel Qays Hashim, Auteur ; Khamis Naba Sayl, Auteur Année de publication : 2021 Article en page(s) : pp 235 - 248 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] algèbre de Boole
[Termes IGN] analyse multicritère
[Termes IGN] barrage
[Termes IGN] combinaison linéaire ponderée
[Termes IGN] eau pluviale
[Termes IGN] Iraq
[Termes IGN] MNS ASTER
[Termes IGN] occupation du sol
[Termes IGN] utilisation du sol
[Termes IGN] zone arideRésumé : (auteur) Water is a key natural resource on earth, especially in arid and semi-arid regions with limited rainfall amounts. The impact of drought could be alleviated via constructing dams to ensure water storage and supply. The aim of the present study is to detect proper sites for planning rainwater harvesting (RWH) in the western desert of Iraq using both the Boolean overlay and the weighted linear combination (WLC) in the geographic information system (GIS). Potential sites of rainwater harvesting were identified using multi-criteria evaluation. Several criteria were used, including physical characteristics and climatological and socio-economic conditions to determine the proper location for RWH. Seven WLC parameters were used in the site selection process: runoff, slope, soil texture, land use/land cover (LULC), distance from irrigated lands, distance from residential areas, and distance from roads, while the Boolean overlay method used the stream order and distance from faults parameters. The results indicated that the final map can be classified into three classes of suitability, i.e., (i) highly suitable with 6% coverage (117 km2), (ii) moderately suitable with 4% coverage (78 km2), and (iii) least suitable with 90% coverage (1758 km2) of the basin area. It was indicated that only three earthen dams could be executed along streams. This low data-intensive and cost-effective methodology offered can be adopted in arid regions to embrace RWH as an efficient strategy to handle growing water scarcity. The proposed method could be adopted in many countries that have identical environmental and physical conditions to the western desert of Iraq, which is the case in most arid regions. Numéro de notice : A2021-411 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s12518-020-00342-3 Date de publication en ligne : 10/10/2020 En ligne : https://doi.org/10.1007/s12518-020-00342-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97736
in Applied geomatics > vol 13 n° 2 (June 2021) . - pp 235 - 248[article]Algebraic method to speed up robust algorithms: example of laser-scanned point clouds / B. Palancz in Survey review, vol 49 n° 357 (December 2017)
[article]
Titre : Algebraic method to speed up robust algorithms: example of laser-scanned point clouds Type de document : Article/Communication Auteurs : B. Palancz, Auteur ; Joseph L. Awange, Auteur ; T. Lovas, Auteur ; R. Lewis, Auteur ; B. Molnar, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 408 - 418 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] bases de Gröbner
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] méthode du maximum de vraisemblance (estimation)
[Termes IGN] Ransac (algorithme)
[Termes IGN] reconstruction d'objet
[Termes IGN] semis de points
[Termes IGN] valeur aberranteRésumé : (auteur) Surface reconstruction from point clouds generated by laser scanning technology has become a fundamental task in many fields of geosciences, such as robotics, computer vision, digital photogrammetry, computational geometry, digital building modelling, forest planning and operational activities. Point clouds produced by laser scanning, however, are limited due to the occurrence of occlusions, multiple reflectance and noise, and off-surface points (outliers), thus necessitating the need for robust fitting techniques. In this contribution, a fast, non-iterative and data invariant algebraic algorithm with constant O(1) complexity that fits planes to point clouds in the total least squares sense using Gaussian-type error distribution is proposed. The maximum likelihood estimator method is used, resulting in a multivariate polynomial system that is solved in an algebraic way. It is shown that for plane fitting when datasets are affected heavily by outliers, the proposed algebraic method can be embedded into the framework of robust methods like the Danish or the RANdom SAmple Consensus methods and computed in parallel to provide rigorous algebraic fitting with significantly reduced running times. Compared to the embedded traditional singular value decomposition and principal component analysis approaches, the performance of the proposed algebraic algorithm demonstrated its efficiency on both synthetic data and real laser-scanned measurements. The evaluation of a symbolic algebraic formula is practically independent of the values of its coefficients; however, the computation of the coefficients depends on the complexity of the data. Since the main advantage of the symbolic solution is its non-requirement of numerical iteration, the data complexity will have weak influence on the speed-up. The novelty of the proposed method is the use of algebraic technique in a robust plane fitting algorithm that could be applied to remote sensing data analysis/delineation/classification. In general, the method could be applied to most plane fitting problems in the geoscience field. Numéro de notice : A2017-755 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/00396265.2016.1183939 En ligne : https://doi.org/10.1080/00396265.2016.1183939 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89109
in Survey review > vol 49 n° 357 (December 2017) . - pp 408 - 418[article]An algebra for spatiotemporal data: From observations to events / Karine Reis Ferreira in Transactions in GIS, vol 18 n° 2 (April 2014)
[article]
Titre : An algebra for spatiotemporal data: From observations to events Type de document : Article/Communication Auteurs : Karine Reis Ferreira, Auteur ; Gilberto Camara, Auteur ; Antônio Miguel V. Monteiro, Auteur Année de publication : 2014 Article en page(s) : pp 253 - 269 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] algèbre
[Termes IGN] analyse spatio-temporelle
[Termes IGN] base de données d'objets mobiles
[Termes IGN] couverture (données géographiques)
[Termes IGN] données spatiotemporelles
[Termes IGN] modélisation
[Termes IGN] risque naturel
[Termes IGN] santé
[Termes IGN] série temporelle
[Termes IGN] service fondé sur la position
[Termes IGN] surveillance écologiqueRésumé : (Auteur) Recent technological advances in geospatial data gathering have created massive data sets with better spatial and temporal resolution than ever before. These large spatiotemporal data sets have motivated a challenge for Geoinformatics: how to model changes and design good quality software. Many existing spatiotemporal data models represent how objects and fields evolve over time. However, to properly capture changes, it is also necessary to describe events. As a contribution to this research, this article presents an algebra for spatiotemporal data. Algebras give formal specifications at a high-level abstraction, independently of programming languages. This helps to develop reliable and expressive applications. Our algebra specifies three data types as generic abstractions built on real-world observations: time series, trajectory and coverage. Based on these abstractions, it defines object and event types. The proposed data types and functions can model and capture changes in a large range of applications, including location-based services, environmental monitoring, public health, and natural disasters. Numéro de notice : A2014-166 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12030 Date de publication en ligne : 22/05/2022 En ligne : https://doi.org/10.1111/tgis.12030 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33071
in Transactions in GIS > vol 18 n° 2 (April 2014) . - pp 253 - 269[article]Toutes les mathématiques, nouveau programme / Luc Verschueren (2014)PermalinkMathématiques Tle [terminale] ES-L / Eric Sigward (2012)PermalinkConnectivity in the regular polytope representation / R. Thompson in Geoinformatica, vol 15 n° 2 (April 2011)PermalinkOrientation relative à partir de 3 points homologues et de la direction verticale : Une approche directe / Mahzad Kalantari in Traitement du signal, vol 27 n° 3 (2010-3)PermalinkPermalinkThe five points pose problem: A new and accurate solution adapted to any geometric configuration / Mahzad Kalantari (2009)PermalinkL'analyse spatiale contre algèbre de cartes : des exemples en sciences de l'homme et de la société / F. Pirot in Géomatique expert, n° 48 (01/01/2006)PermalinkA generalized cross-tabulation matrix to compare soft-classified maps at multiple resolutions / Robert Gilmore Pontius in International journal of geographical information science IJGIS, vol 20 n° 1 (january 2006)PermalinkSolving algebraic computational problems in geodesy and geoinformatics / Joseph L. Awange (2005)PermalinkLes progrès des méthodes géodésiques : instruments ou moyens de calcul ? / Michel Kasser in XYZ, n° 101 (décembre 2004 - février 2005)Permalink