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Geographic Information Systems in Geospatial Intelligence, ch. 5. Spectral optimization of airborne multispectral camera for land cover classification: automatic feature selection and spectral band clustering / Arnaud Le Bris (2019)
Titre de série : Geographic Information Systems in Geospatial Intelligence, ch. 5 Titre : Spectral optimization of airborne multispectral camera for land cover classification: automatic feature selection and spectral band clustering Type de document : Chapitre/Contribution Auteurs : Arnaud Le Bris , Auteur ; Nesrine Chehata , Auteur ; Xavier Briottet , Auteur ; Nicolas Paparoditis , Auteur Editeur : London [UK] : IntechOpen Année de publication : 2019 Projets : 1-Pas de projet / Importance : 4 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] bande spectrale
[Termes IGN] carte d'occupation du sol
[Termes IGN] classification multibande
[Termes IGN] image hyperspectrale
[Termes IGN] optimisation (mathématiques)Résumé : (auteur) Hyperspectral imagery consists of hundreds of contiguous spectral bands. However, most of them are redundant. Thus a subset of well-chosen bands is generally sufficient for a specific problem, enabling to design adapted superspectral sensors dedicated to specific land cover classification. Related both to feature selection and extraction, spectral optimization identifies the most relevant band subset for specific applications, involving a band subset relevance score as well as a method to optimize it. This study first focuses on the choice of such relevance score. Several criteria are compared through both quantitative and qualitative analyses. To have a fair comparison, all tested criteria are compared to classic hyperspectral data sets using the same optimization heuristics: an incremental one to assess the impact of the number of selected bands and a stochastic one to obtain several possible good band subsets and to derive band importance measures out of intermediate good band subsets. Last, a specific approach is proposed to cope with the optimization of bandwidth. It consists in building a hierarchy of groups of adjacent bands, according to a score to decide which adjacent bands must be merged, before band selection is performed at the different levels of this hierarchy. Numéro de notice : H2019-008 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Chapître / contribution nature-HAL : ChOuvrScient DOI : 10.5772/intechopen.88507 Date de publication en ligne : 20/12/2019 En ligne : http://dx.doi.org/10.5772/intechopen.88507 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95734 Hyperparameter optimization of neural network-driven spatial models accelerated using cyber-enabled high-performance computing / Minrui Zheng in International journal of geographical information science IJGIS, Vol 33 n° 1-2 (January - February 2019)
[article]
Titre : Hyperparameter optimization of neural network-driven spatial models accelerated using cyber-enabled high-performance computing Type de document : Article/Communication Auteurs : Minrui Zheng, Auteur ; Wenwu Tang, Auteur ; Xiang Zhao, Auteur Année de publication : 2019 Article en page(s) : pp 314 - 345 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Intelligence artificielle
[Termes IGN] algorithme d'apprentissage
[Termes IGN] analyse spatiale
[Termes IGN] apprentissage profond
[Termes IGN] Caroline du Nord (Etats-Unis)
[Termes IGN] données spatiotemporelles
[Termes IGN] géostatistique
[Termes IGN] méthode des moindres carrés
[Termes IGN] modèle empirique
[Termes IGN] modèle numérique de surface
[Termes IGN] modélisation spatiale
[Termes IGN] optimisation (mathématiques)
[Termes IGN] régression linéaire
[Termes IGN] réseau neuronal artificiel
[Termes IGN] système d'information foncièreRésumé : (auteur) Artificial neural networks (ANNs) have been extensively used for the spatially explicit modeling of complex geographic phenomena. However, because of the complexity of the computational process, there has been an inadequate investigation on the parameter configuration of neural networks. Most studies in the literature from GIScience rely on a trial-and-error approach to select the parameter setting for ANN-driven spatial models. Hyperparameter optimization provides support for selecting the optimal architectures of ANNs. Thus, in this study, we develop an automated hyperparameter selection approach to identify optimal neural networks for spatial modeling. Further, the use of hyperparameter optimization is challenging because hyperparameter space is often large and the associated computational demand is heavy. Therefore, we utilize high-performance computing to accelerate the model selection process. Furthermore, we involve spatial statistics approaches to improve the efficiency of hyperparameter optimization. The spatial model used in our case study is a land price evaluation model in Mecklenburg County, North Carolina, USA. Our results demonstrate that the automated selection approach improves the model-level performance compared with linear regression, and the high-performance computing and spatial statistics approaches are of great help for accelerating and enhancing the selection of optimal neural networks for spatial modeling. Numéro de notice : A2019-022 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2018.1530355 Date de publication en ligne : 12/10/2018 En ligne : https://doi.org/10.1080/13658816.2018.1530355 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91689
in International journal of geographical information science IJGIS > Vol 33 n° 1-2 (January - February 2019) . - pp 314 - 345[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2019011 RAB Revue Centre de documentation En réserve L003 Disponible Optimisation of GNSS networks, considering baseline correlations / M. Amin Alizadeh-Khameneh in Survey review, vol 51 n° 364 (January 2019)
[article]
Titre : Optimisation of GNSS networks, considering baseline correlations Type de document : Article/Communication Auteurs : M. Amin Alizadeh-Khameneh, Auteur ; Lars E. Sjöberg, Auteur ; Anna B. O. Jensen, Auteur Année de publication : 2019 Article en page(s) : pp 35 - 42 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] corrélation
[Termes IGN] données GNSS
[Termes IGN] double différence
[Termes IGN] ligne de base
[Termes IGN] optimisation (mathématiques)
[Termes IGN] réseau géodésique local
[Termes IGN] SuèdeRésumé : (Auteur) By considering global navigation satellite system (GNSS) observations, one can perform optimisation according to some pre-defined criteria and come up with the best location of receivers and optimum number of baselines. In practice, it is quite common to neglect the effect of correlations between baselines, and instead assume single-baseline-adjusted data in the optimisation procedure. However, in each session of observation, usually more than two receivers are simultaneously taking data from a number of common GNSS satellites, implying that the single- or double-difference observations are correlated. Our study designs an optimal observation plan for a GPS network in Skåne in southern Sweden, with the aim of determining possible displacements. Assuming three receivers in each session of observations leads to correlation between the GPS baselines, and consequently a fully populated weight matrix for each session of observation. A bi-objective optimisation model of precision and reliability is chosen to optimise the variance factor of each session, and eventually, design an observation plan. It is shown in this study that observing six out of ten possible sessions is sufficient to enable the network to detect a 5 mm displacement at each station. Assuming that the double-difference phase observations are uncorrelated changes the observation plan by retaining two more sessions. However, defining the weight matrix based on the double-difference observations requires the correlations to be taken into account, and neglecting them leads to incorrect results. Numéro de notice : A2019-187 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Numéro de périodique nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2017.1342896 Date de publication en ligne : 26/06/2017 En ligne : https://doi.org/10.1080/00396265.2017.1342896 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92618
in Survey review > vol 51 n° 364 (January 2019) . - pp 35 - 42[article]
Titre : Optimization in control applications Type de document : Monographie Auteurs : Guillermo Valencia-Palomo, Éditeur scientifique ; Francisco Ronay Lopez-Estrada, Éditeur scientifique Editeur : Bâle [Suisse] : Multidisciplinary Digital Publishing Institute MDPI Année de publication : 2019 Importance : 256 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-3-03897-448-2 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Mathématique
[Termes IGN] modèle mathématique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] programmation stochastiqueRésumé : (auteur) Mathematical optimization is the selection of the best element in a set with respect to a given criterion. Optimization has become one of the most-used tools in modern control theory for computing the control law, adjusting the controller parameters (tuning), model fitting, and finding suitable conditions in order to fulfill a given closed-loop property, among others. In the simplest case, optimization consists of maximizing or minimizing a function by systematically choosing input values from a valid input set and computing the function value. Nevertheless, real-world control systems need to comply with several conditions and constraints that have to be taken into account in the problem formulation—these represent challenges in the application of the optimization algorithms.The aim of this Special Issue is to offer the state-of-the-art of the most advanced optimization techniques (online and offline) and their applications in control engineering.] Note de contenu : 1- Rapid solution of optimal control problems by a functional spreadsheet paradigm: A practical method for the non-programme
2- Novel spreadsheet direct method for optimal control problems
3- Time needed to control an epidemic with restricted resources in SIR model with short-term controlled population: A fixed point method for a free isoperimetric optimal control problem
4- Optimal strategies for psoriasis treatment
5- Optimal control analysis of a mathematical model for breast cancer
6- Cost-effective analysis of control strategies to reduce the prevalence of cutaneous
leishmaniasis, based on a mathematical model
7- Optimal control and computational method for the resolution of isoperimetric problem in a discrete-time SIRS system
8- Solution of optimal harvesting problem by finite difference approximations of
size-structured population model
9- Solution of fuzzy differential equations using fuzzy Sumudu transforms
10- A simple spectral observer
11- Differential evolution algorithm for multilevel assignment problem: A case study in chicken transportation
12- Modeling and simulation of a hydraulic network for leak diagnosisNuméro de notice : 28503 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Monographie DOI : 10.3390/books978-3-03897-448-2 En ligne : https://doi.org/10.3390/books978-3-03897-448-2 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97002 Optimization of optical clock network for the geopotential determination / Guillaume Lion (2019)
Titre : Optimization of optical clock network for the geopotential determination Type de document : Article/Communication Auteurs : Guillaume Lion , Auteur ; Isabelle Panet , Auteur ; David Coulot , Auteur ; Pacôme Delva, Auteur Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2019 Conférence : AGU 2019 Fall Meeting 09/12/2019 13/12/2019 San Francisco Californie - Etats-Unis programme sans actes Projets : ChronoG2o / Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] chronométrie
[Termes IGN] décalage d'horloge
[Termes IGN] horloge optique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] potentiel de pesanteur terrestreRésumé : (auteur) Clock comparisons with an uncertainty at the 10−18 in terms of relative frequency can provide a new kind of measurement to improve our knowledge of Earth’s gravity field and geoid. Instead of using state-of-the-art Earth’s gravitational field models to predict frequency shifts between distant clocks, they could permit determining geopotential differences at a centimeter-level accuracy, and question the possibility of studying geodynamic processes leading to very small vertical deformations or improve the unification of height systems. In our previous work dealing with the geopotential determination at high spatial resolution in mountainous regions, we have pointed out that clock-based geodetic observable can provide useful information at spatial scales beyond what is available from satellites and they could be used to fill areas not covered by the gravity data on the ground. Our synthetic simulations have shown that adding few clock-based potential data to a gravimetric data set can significantly improve the reconstruction of the geopotential. Therefore, it turns out there is a large variety of possible clock distribution allowing to reduce the reconstruction residuals, with different locations and number of clocks. In this work, we investigate ways to optimize clock network from a gravimetric data set in the Massif Central region in order to know where to put them to minimize the residuals and improve further the determination of the geopotential. To do that, we have used a multi-objective genetic algorithm (GA). Starting from a random initial population with different clock distributions, the algorithm selects clock locations with good chances of reproduction and reproduces the new generation of clock locations using genetic operators. The process depends on some objectives we want to reach in order to solve the optimization problem, and it is repeated several times for a given number of generations or until a solution considered as optimum is found. We show how GA can help to provide optimal solutions for a problem with a fixed and variable number of clock locations. We discuss the effect of different parameters, such as the way to define the objectives and the constrains of the problem, the quality of the clock network and the data. Numéro de notice : C2019-057 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Poster nature-HAL : Poster-avec-CL DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96833 PermalinkPermalinkQuery rewriting for semantic query optimization in spatial databases / Eduardo Mella in Geoinformatica, vol 23 n° 1 (January 2019)PermalinkRetour d'expérience de l'école OpenMOLE "ExModelo", organisée en partenariat avec le méso-centre du CRIANN / Mathieu Leclaire (2019)PermalinkVariational learning of mixture wishart model for PolSAR image classification / Qian Wu in IEEE Transactions on geoscience and remote sensing, vol 57 n° 1 (January 2019)PermalinkUn algorithme pour battre le record du SwissTrainChallenge : poser le pied dans chacun des 26 cantons le plus rapidement possible en utilisant uniquement des transports publics / Emmanuel Clédat in XYZ, n° 157 (décembre 2018 - février 2019)PermalinkEtude de faisabilité et choix optimal d'une station RIMS d'EGNOS en Algérie / Tabti Lahouaria in XYZ, n° 157 (décembre 2018 - février 2019)Permalink3D WebGIS : from visualization to analysis. An efficient browser-based 3D line-of-sight analysis / Michael Auer in ISPRS International journal of geo-information, vol 7 n° 7 (July 2018)PermalinkA context-based geoprocessing framework for optimizing meetup location of multiple moving objects along road networks / Shaohua Wang in International journal of geographical information science IJGIS, vol 32 n° 7-8 (July - August 2018)PermalinkHuman mobility semantics analysis : a probabilistic and scalable approach / Xiaohui Guo in Geoinformatica, vol 22 n° 3 (July 2018)Permalink