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Évaluation et spatialisation du potentiel offert par les moyens d'alerte centrés sur la localisation des individus / Esteban Bopp (2021)
Titre : Évaluation et spatialisation du potentiel offert par les moyens d'alerte centrés sur la localisation des individus : expérimentations à différentes échelles en France Type de document : Thèse/HDR Auteurs : Esteban Bopp, Auteur ; Johnny Douvinet, Directeur de thèse Editeur : Avignon : Université d'Avignon Année de publication : 2021 Importance : 342 p. Format : 21 x 30 cm Note générale : Bibliographie
Thèse en vue d'obtenir le grade de Docteur de Avignon Université, Spécialité GéographieLangues : Français (fre) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] analyse spatiale
[Termes IGN] commune
[Termes IGN] échelle géographique
[Termes IGN] France (administrative)
[Termes IGN] géolocalisation
[Termes IGN] message d'alerte
[Termes IGN] téléphone intelligent
[Termes IGN] test de performance
[Termes IGN] utilisateur nomadeIndex. décimale : THESE Thèses et HDR Résumé : (Auteur) Le 24 septembre 2020, le ministère de l’Intérieur a annoncé la mise en place, au plus tard en 2022, de deux moyens d’alerte centrés sur la localisation des individus en temps réel : le Cell Broadcast (CB) et le SMS géolocalisé (LB-SMS). Ces deux LBAS (Location-Based Alerting System) permettent la diffusion d’alertes plus massives, plus rapides, et spatialisées (Aloudat, 2010). Cette thèse, qui a devancé un tel choix politique, propose d’estimer le potentiel de ces LBAS et d’analyser la manière dont ces moyens peuvent améliorer l’alerte à la population en France. À l’aide de protocoles méthodologiques variés et reposants sur les méthodes issues de l’analyse spatiale, nous démontrons le haut potentiel de performance du CB et du LB-SMS à l’échelle nationale. Les taux d’individus alertables par ces solutions sont très hauts et le niveau d’alertabilité des communes est très homogène. Ces outils sont aussi bien acceptés par la population. Autrement dit, ces deux solutions offrent de nouvelles opportunités pour venir pallier les faiblesses des moyens traditionnels. Il est toutefois nécessaire d’adapter ces solutions aux contextes sociaux et territoriaux. Leur intégration dans la future plateforme FR-Alert et notamment les motifs d’utilisation doivent être réfléchis, en évitant tout fétichisme technologique et en adaptant les organisations à ces mutations, ce qui peut parfois prendre (beaucoup) de temps. Note de contenu : Introduction générale
PREMIÈRE PARTIE - Diffuser une alerte à la population en France : constats, limites et opportunités
Chapitre 1 - L’alerte : une notion multidimensionnelle à appréhender à différentes échelles en France
Chapitre 2 - Les disparités spatiales de l’alerte par sirènes
Chapitre 3 - Apports et limites de l’alerte centrée sur la localisation des individus
DEUXIÈME PARTIE - Évaluer le potentiel des LBAS en France : développements méthodologiques
Chapitre 4 - Évaluation du potentiel offert par les applications mobiles d’alerte en France
Chapitre 5 - Évaluation du potentiel de performance spatiale des LBAS en France métropolitaine
Chapitre 6 - Évaluation de l’acceptabilité des LBAS
TROISIÈME PARTIE - Contributions à la géographie de l’alerte : enjeux et perspectives
Chapitre 7 - Comment adapter l’offre aux territoires ? Investigations à l’échelle communale
Chapitre 8 - Quel regard géographique porter face à la mise en œuvre de la plateforme nationale FR-Alert ?
Chapitre 9 - Quelles perspectives d’évolution pour les systèmes d’alerte nationaux ?
Conclusion généraleNuméro de notice : 26562 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse française Note de thèse : Thèse de Doctorat : Spécialité Géographie : Avignon : 2021 Organisme de stage : UMR Étude des Structures, des Processus d’Adaptation et des Changements de l’Espace ESPACE nature-HAL : Thèse DOI : sans Date de publication en ligne : 24/06/2021 En ligne : https://theses.hal.science/tel-03637612/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98252
Titre : GNSS/5G Hybridization for Urban Navigation Type de document : Thèse/HDR Auteurs : Anne-Marie Tobie, Auteur ; Axel Javier Garcia Pena, Directeur de thèse ; Paul Thevenon, Directeur de thèse Editeur : Toulouse : Université Fédérale Toulouse Midi-Pyrénées Année de publication : 2021 Importance : 287 p. Format : 21 x 30 cm Note générale : Bibliographie
Thèse pour obtenir le doctorat de l'Université de Toulouse, Spécialité Informatique et TélécommunicationsLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] 4G
[Termes IGN] 5G
[Termes IGN] bruit blanc
[Termes IGN] GNSS assisté pour la navigation
[Termes IGN] milieu urbain
[Termes IGN] modèle mathématique
[Termes IGN] positionnement en intérieur
[Termes IGN] positionnement par GNSS
[Termes IGN] signal Galileo
[Termes IGN] signal GPS
[Termes IGN] simulation de signal
[Termes IGN] temps de propagation
[Termes IGN] trajet multipleIndex. décimale : THESE Thèses et HDR Résumé : (Auteur) Over the past few years, the need for positioning, and thus the number of positioning services in general, has been in constant growth. This need for positioning has been increasingly focused on constrained environments, such as urban or indoor environments, where GNSS (Global Navigation Satellite System) is known to have significant limitations: multipath as well as the lack of Line-of-Sight (LOS) satellite visibility degrades the GNSS positioning solution and makes it unsuitable for some urban or indoor applications. In order to improve the GNSS positioning performance in constrained environments, many solutions are already available: hybridization with additional sensors, [1], [2] or the use of signals of opportunity (SoO) for example, [3], [4], [5], [6], [7], [8]. Concerning SoO, mobile communication signals, such as the 4G Long Term Evolution (LTE) or 5G, are naturally envisioned for positioning, [3], [9], [10]. Indeed, a significant number of users are expected to be “connected-users” and 5G systems offers promising opportunities. 5G technology is being standardized at 3GPP [11]; the first complete release of 5G specifications, Release-15, was provided to the community in March 2018. 5G is an emerging technology and its positioning performance, as well as a potential generic receiver scheme to conduct positioning operations, is still under analysis. In order to study the potential capabilities provided by 5G systems and to develop a 5G-based generic positioning module scheme, the first fundamental step is to develop mathematical models of the processed 5G signals at each stage of the receiver for realistic propagation channel models: the mathematical expression of the useful received 5G signal as well as the AWG (Additive White Gaussian) noise statistics. In the Ph.D., the focus is given to the correlation operation which is the basic function implemented by typical ranging modules for 4G LTE signals [12], DVB signals [7], [8], and GNSS [13]. In fact, the knowledge of the correlation output mathematical model could allow for the development of optimal 5G signal processing techniques for ranging positioning. Previous efforts were made to provide mathematical models of received signals at the different receiver signal processing stages for signals with similar structures to 5G signals – Orthogonal Frequency Division Multiplexing (OFDM) signals as defined in 3GPP standard, [14]. OFDM signal-type correlator output mathematical model and acquisition techniques were derived in [7], [15]. Moreover, in [8], [15], tracking techniques were proposed, analyzed and tested based on the correlator output mathematical model of [7]. However, these models were derived by assuming a constant propagation channel over the duration of the correlation. Unfortunately, when the Channel Impulse Response (CIR) provided by a realistic propagation channel is not considered to be constant over the duration of the correlation, the correlator output mathematical models are slightly different from the mathematical models proposed in [7], [8]. Therefore, the first main point considered in the Ph.D. consists in the development of mathematical models and statistics of processed 5G signals for positioning. In order to derive accurate mathematical models, the time evolution impact of the 5G standard compliant propagation channel is of the utmost importance. Note that, in the Ph.D., the continuous CIR will be approximated by a discretized CIR, and the continuous time-evolution will be replaced by the propagation channel generation sampling rate notion. This approximation makes sense since, in a real transmission/reception chain, the received time-continuous signal is, at the output of the Radio-Frequency (RF) front-end, sampled. Therefore, a preliminary step, prior to derive accurate mathematical models of processed 5G signals, consists in determining the most suitable CIR-generation sampling interval for a selected 5G standard compliant propagation channel, QuaDRiGa: trade-off between having a realistic characterization and its complexity. Complexity is especially important for 5G compliant channels with multiple emitter and receiver antennas, and high number of multipath. Then, the impact of a time-evolving propagation channel inside an OFDM symbol duration is studied. A method to select the most appropriate CIR sampling interval for accurate modelling of symbol demodulation, correlator outputs and delay tracking will also be proposed. Based on the correlator output mathematical models developed for realistic multipath environments for both GNSS and 5G systems, ranging modules are then developed. These ranging modules outputs the pseudo ranging measurements required to develop navigation solution. In order to improve the positioning availability and GNSS positioning performance in urban environment through the exploitation of 5G signals, both systems, GNSS and 5G communication systems, must be optimally combined. In fact, in order to achieve this optimal combination, both types of signals must be optimally processed, and the mathematical model of their generated pseudo range measurements must be accurately characterized. The second main objective of the Ph.D. aims thus at realistically characterizing GNSS and 5G pseudo range measurement mathematical models and at developing hybrid navigation modules exploiting/adapted to the derived pseudo range measurements mathematical models. In order to validate, the mathematical models developed in the Ph.D., a simulator is designed. The pseudo range measurements mathematical models are derived from a realistic simulator which integrates a typical GNSS receiver processing module and a typical 5G signal processing module proposition; moreover, in order to achieve a realistic characterization, the simulator implements highly realistic propagation channels for GNSS, SCHUN [16], and for 5G, QuaDRiGa [17] is developed. The hybrid navigation modules to be implemented and compared in this work are an Extended Kalman Filter (EKF) and an Unscented Kalman Filter (UKF). The performances of these hybrid navigation modules are then studied to quantify the improvements bringing by 5G TOA measurements. Note de contenu : 1- Introduction
2- GNSS signals, measurement model and positioning
3- 5G systems
4- Mathematical models and statistics of processed 5G signals for ranging based positioning for a realistic propagation channel
5- Synchronization module of a 5G signal
6- Characterization of pseudo range measurement errors due to propagation channels
7- Positioning in urban environment using 5G and GNSS measurements
8- ConclusionNuméro de notice : 26526 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT/URBANISME Nature : Thèse française Note de thèse : Thèse de Doctorat : Informatique et Télécommunications : Toulouse : 2021 Organisme de stage : Laboratoire de recherche ENAC nature-HAL : Thèse Date de publication en ligne : 09/04/2021 En ligne : https://hal.science/tel-03189527/ Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97534 Improving smartphone-based GNSS positioning using state space augmentation techniques / Francesco Darugna (2021)
Titre : Improving smartphone-based GNSS positioning using state space augmentation techniques Type de document : Thèse/HDR Auteurs : Francesco Darugna, Auteur ; Steffen Schön, Directeur de thèse Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 2021 Collection : DGK - C, ISSN 0065-5325 num. 864 Importance : 189 p. Note générale : bibliographie
Diese Arbeit ist gleichzeitig veröffentlicht in:Wissenschaftliche Arbeiten der Fachrichtung Geodäsie und Geoinformatik der Universität Hannover - ISSN 0174-1454, Nr. 368, Hannover 2021Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Navigation et positionnement
[Termes IGN] antenne GNSS
[Termes IGN] étalonnage d'instrument
[Termes IGN] positionnement par GNSS
[Termes IGN] retard troposphérique zénithal
[Termes IGN] téléphone intelligentRésumé : (auteur) Low-cost receivers providing Global Navigation Satellite System (GNSS) pseudorange and carrier phase raw measurements for multiple frequencies and multiple GNSS constellations have become available on the market in the last years. This significantly has increased the number of devices equipped with the necessary sensors to perform precise GNSS positioning. GNSS pseudorange and carrier phase are used to compute user positions. While both observations are affected by different error sources, e.g. the passage through the atmosphere, only the carrier-phase has an ambiguous nature. The resolution of this ambiguity is a crucial factor to reach fast and highly precise GNSS-based positioning. Currently, several smartphones are equipped with a dual-frequency, multi-constellation receiver. The access to Android-based GNSS raw measurements has become a strong motivation to investigate the feasibility of smartphone-based high-accuracy positioning. The quality of smartphone GNSS measurements has been analyzed, suggesting that they often suffer from low signal-to-noise, inhomogeneous antenna gain and high levels of multipath. This workshows how to tackle several of the currently present obstacles and demonstrates centimeter-level positioning with a low-cost GNSS antenna and a low-cost GNSS receiver built into an off-the-shelf smartphone. Since the beginning of the research in smartphone-based positioning, the device’s GNSS antenna has been recognized as one of the main limitations. Besides Multipath (MP), the antenna radiation pattern is the main site-dependent error source of GNSS observations. An absolute antenna calibration has been performed for the dual-frequency smartphone HuaweiMate20X. Antenna Phase Center Offset (PCO), and Variations (PCV ) have been estimated to correct for the antenna impact on the L1 and L5 phase observations. Accordingly, the relevance of considering the individual PCO and PCV for the two frequencies is shown. The PCV patterns indicate absolute values up to 2 cm and 4 cm for L1 and L5, respectively. The impactof antenna corrections has been assessed in different multipath environments using a high-accuracy positioning algorithm employing an uncombined observation model and applying Ambiguity Resolution (AR). Experiments both in zero-baseline and short-baseline configurations have been performed. Instantaneous AR in the zero-baseline setup has been demonstrated, showing the potential for cm-level positioning with low-cost sensors available inside smartphones. In short-baselines configurations, no reliable AR is achieved without antenna corrections. However, after correcting for PCV, successful AR is demonstrated for a smartphone placed in a low multipath environment on the ground of a soccer field. For a rooftop open-skytest case with large multipath, AR was successful in 19 out of 35 data-sets. Overall, the antenna calibration is demonstrated being an asset for smartphone-based positioning with AR,showing cm-level 2D Root Mean Square Error (RMSE). In GNSS-based positioning, a user within a region covered by a network of reference stations can take advantage of the network-estimated augmentation parameters. Among the GNSS error sources, atmospheric delays have a strong impact on the positioning performance and the ability to resolve ambiguities. State Space Representation (SSR) atmospheric corrections, i.e. tropospheric and ionospheric delays, are commonly estimated for the approximate user position by interpolation from values calculated for the reference stations. Widely used interpolation techniques are Inverse Distance Weighted (IDW), Ordinary Kriging (OK)and Weighted Least Squares (WLS). The interpolation quality of such techniques during severe weather events and Traveling Ionospheric Disturbances (TIDs) is analyzed. To improve the interpolation performance during such events, modified WLS methods taking advantage of the physical atmospheric behavior are proposed. To support this interpolation approach, external information from Numerical Weather Models (NWM) for tropospheric interpolation and from TID modeling for ionospheric interpolation is introduced to the algorithms. The interpolation is assessed using simulated data (considering artificial and real network geometries), and real SSR parameters generated by network computation of GNSS measurements. As examples, two severe weather events in northern Europe in 2017 and one TID eventover Japan in 2019 have been analyzed. The interpolation of SSR Zenith Tropospheric Delay(ZTD) and ionospheric parameters is evaluated. Considering the reference station positions as rover locations, the modified WLS approach marks a lower RMSE in up to 80% of the cases during sharp weather fluctuations. Also, the average error can be decreased in 64% of the cases during the TID event investigated. Improvements up to factors larger than two are observed. Furthermore, specific cases are isolated, showing particular ZTD variations where significant errors (e.g. larger than 1 cm) can be reduced by up to 20% of the total amount. As a final product of the analysis, tropospheric and ionospheric messages are proposed. The messages contain the information needed to implement the suggested interpolation. Along with the need for accurate atmospheric models, the concept of consistency in the SSR corrections is crucial. A format that can transport all the SSR corrections estimated by a network is the Geo++ SSR format (SSRZ). Exploiting the features of the SSRZ format, the impact of an error in the transported ionospheric parameters is investigated. It is shown that the position estimation strongly depends on the ionospheric modeling and mismodeling can result in cm level errors, especially in the height component. Numéro de notice : 17182 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Note de thèse : Thesis : Geodäsie und Geoinformatik : Hanovre : 2021 En ligne : https://dgk.badw.de/fileadmin/user_upload/Files/DGK/docs/c-864.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98000 Probabilistic positioning in mobile phone network and its consequences for the privacy of mobility data / Aleksey Ogulenko in Computers, Environment and Urban Systems, vol 85 (January 2021)
[article]
Titre : Probabilistic positioning in mobile phone network and its consequences for the privacy of mobility data Type de document : Article/Communication Auteurs : Aleksey Ogulenko, Auteur ; Itzhak Benenson, Auteur ; Itzhak Omer, Auteur Année de publication : 2021 Article en page(s) : n° 101550 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] antenne
[Termes IGN] classification bayesienne
[Termes IGN] confidentialité
[Termes IGN] diagramme de Voronoï
[Termes IGN] estimation bayesienne
[Termes IGN] géolocalisation
[Termes IGN] inférence
[Termes IGN] protection de la vie privée
[Termes IGN] réseau téléphonique
[Termes IGN] téléphonie mobile
[Termes IGN] tessellationRésumé : (auteur) The traditional approach to mobile phone positioning is based on the assumption that the geographical location of a cell tower recorded in a Call Details Record (CDR) is a proxy for a device's location. A Voronoi tessellation is then constructed based on the entire network of cell towers and this tessellation is considered as a coordinate system, with the device located in a Voronoi polygon of a cell tower that is recorded in the CDR. If Voronoi-based positioning is correct, the uniqueness of the device trajectory is very high, and the device can be identified based on 3–5 of its recorded locations. We investigate a probabilistic approach to device positioning that is based on knowledge of each antennas' parameters and number of connections, as dependent on the distance to the antenna. The critical difference between the Voronoi-based and the real world layout is in the essential overlap of the antennas' service areas: The device that is located in a cell tower's polygon can be served by a more distant antenna that is chosen by the network system to balance the network load. Combining data on the distance distribution of the number of connections available for each antenna in the network, we resolve the overlap problem by applying Bayesian inference and construct a realistic distribution of the device location. Probabilistic device positioning demands a full revision of mobile phone privacy and new full set of tools for data analysis. Numéro de notice : A2021-005 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/MATHEMATIQUE Nature : Article DOI : 10.1016/j.compenvurbsys.2020.101550 Date de publication en ligne : 14/10/2020 En ligne : https://doi.org/10.1016/j.compenvurbsys.2020.101550 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96272
in Computers, Environment and Urban Systems > vol 85 (January 2021) . - n° 101550[article]Toward green cartography & visualization: a semantically-enriched method of generating energy-aware color schemes for digital maps / Yangli Han in Cartography and Geographic Information Science, vol 48 n° 1 (January 2021)
[article]
Titre : Toward green cartography & visualization: a semantically-enriched method of generating energy-aware color schemes for digital maps Type de document : Article/Communication Auteurs : Yangli Han, Auteur ; Mingguang Wu, Auteur ; Robert Emmett Roth, Auteur Année de publication : 2021 Article en page(s) : pp 43 - 62 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] amélioration des couleurs
[Termes IGN] cartographie pour écran mobile
[Termes IGN] conception cartographique
[Termes IGN] couleur (rédaction cartographique)
[Termes IGN] économie d'énergie
[Termes IGN] enrichissement sémantique
[Termes IGN] impact sur l'environnement
[Termes IGN] optimisation (mathématiques)
[Termes IGN] relation sémantique
[Termes IGN] téléphone intelligent
[Termes IGN] visualisation cartographique
[Vedettes matières IGN] GéovisualisationRésumé : (auteur) We introduce a semantically-enriched method of generating color schemes for various types of digital maps that reduces the energy consumption of the display device while preserving the quality of the original design. Energy-aware design intersects two important trends in cartography. First, as more maps are viewed today on mobile, battery life has become a central constraint influencing design. Second, there is increasing need for green computing, which encourages the efficient use of energy to limit environmental impacts. This paper focuses on one important aspect of energy-aware cartography: color design. Existing research on energy-aware color adjustment methods apply broadly to images or websites. However, the colors used in maps have more structured semantic relationships than most documents viewed on mobile devices, and efforts to account for these relationships while reducing energy consumption are limited. To fill this gap, we mathematically formalize energy-aware map-color adjustment as a constrained optimization problem: we define energy consumption as the objective function and model the preservation of semantic relationships as the search constraints. We evaluate our proposed method against a common color dimming method using four maps with different semantic relationships. The evaluation suggests that our proposed method better preserves the original color semantics. Numéro de notice : A2021-018 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/15230406.2020.1827040 Date de publication en ligne : 05/11/2020 En ligne : https://doi.org/10.1080/15230406.2020.1827040 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96457
in Cartography and Geographic Information Science > vol 48 n° 1 (January 2021) . - pp 43 - 62[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 032-2021011 RAB Revue Centre de documentation En réserve L003 Disponible How urban places are visited by social groups? Evidence from matrix factorization on mobile phone data / Chaogui Kang in Transactions in GIS, Vol 24 n° 6 (December 2020)PermalinkUrban Wi-Fi fingerprinting along a public transport route / Guenther Retscher in Journal of applied geodesy, vol 14 n° 4 (October 2020)PermalinkFine-scale dasymetric population mapping with mobile phone and building use data based on grid Voronoi method / Zhenzhong Peng in ISPRS International journal of geo-information, vol 9 n° 6 (June 2020)PermalinkGéodésie de poche : toute la géodésie dans votre main / Gilles Canaud in XYZ, n° 163 (juin 2020)PermalinkIndoor positioning using PnP problem on mobile phone images / Hana Kubickova in ISPRS International journal of geo-information, vol 9 n° 6 (June 2020)PermalinkCrowdsource mapping of target buildings in hazard: the utilization of smartphone technologies and geographic services / Mohammad H. Vahidnia in Applied geomatics, vol 12 n° 1 (April 2020)PermalinkPermalinkEvaluation des mesures GPS effectuées par un smartphone Android Xiaomi Mi 8 / Umberto Robustelli in Géomatique expert, n° 132-133 (janvier - septembre 2020)PermalinkRevealing the Correlation between Population Density and the Spatial Distribution of Urban Public Service Facilities with Mobile Phone Data / Yi Shi in ISPRS International journal of geo-information, Vol 9 n° 1 (January 2020)PermalinkPermalink