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Gold deposition in structurally controlled deposits is triggered by changes in the mineralizing fluid conditions. Recent research has demonstrated that in deposits with a well-established paragenesis, the processes that control the ore-forming fluid conditions, and thus the gold timing and deposition, can be inferred from the study of both textural and chemical characteristics of ore-bearing minerals such as sulfides, which are ubiquitous in almost every gold deposit type. In this contribution, we carried out a coupled investigation of (1) microscopic-scale expression of regional deformation, (2) textures of mineralized veins and pyrite generations, and (3) laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) trace element concentrations in pyrite from the Neoproterozoic Central Zone gold deposit, located in the poorly studied Gabgaba gold district, central Keraf suture, Sudanese Nubian shield. The Central Zone gold mineralization is associated with late-collisional Keraf strike-slip shearing. It is expressed by visible gold-bearing quartz-ankerite-(albite) conjugate veins hosted by metagranitoids surrounded by metasediments. Some structurally lattice-bound gold occurs in proximal As-Au-Ni–enriched pyrite associated with sericite-albite-ankerite alteration. Vein textures and proximal pyrite oscillatory zoning and geochemical signatures indicate that vein infilling occurred as a response to sudden pressure drops and boiling of the mineralizing fluid. We therefore interpret the Central Zone deposit as a typical orogenic gold deposit, with microtextural evidence and geochemical data supporting the existence of earthquake-induced fault-valve processes.

Integrating structural control on mineralization and geochemical ore-forming processes is crucial when studying deformed ore deposits. Yet structural and geochemical data are rarely acquired at the same scale: structural control on mineralization is typically investigated from the district to the deposit and macroscopic scales whereas geochemical ore processes are described at the microscopic scale. The deciphering of a deformation–mineralization history valid at every scale thus remains challenging. This study proposes a multiscale approach that enables the reconciliation of structural and geochemical information collected at every scale, applied to the example of the Galat Sufar South gold deposit, Nubian shield, NE Sudan. It gathers field and laboratory information by coupling a classical petrological–structural study with high-resolution X-ray computed tomography, electron back-scattered diffraction and laser ablation inductively coupled plasma mass spectrometry on mineralized sulfide mineral assemblages. This approach demonstrates that there is a linear control on mineralization expressed from the district to microscopic scales at the Galat Sufar South gold deposit. We highlight the relationships between Atmur–Delgo suturing tectonics, microdeformation of sulfide minerals, syn-pyrite recrystallization metal remobilization, gold liberation and ore upgrading. Our contribution therefore represents another step forward in a holistic field-to-laboratory approach for the study of any other sulfide-bearing, structurally controlled ore deposit type.

International audience; Maps have been a unique source of knowledge for centuries. Such historical documents provide invaluable information for analyzing the complex spatial transformation of landscapes over important time frames. This is particularly true for urban areas that encompass multiple interleaved research domains (social sciences, economy, etc.). The large amount and significant diversity of map sources call for automatic image processing techniques in order to extract the relevant objects under a vectorial shape. The complexity of maps (text, noise, digiti-zation artifacts, etc.) has hindered the capacity of proposing a versatile and efficient raster-to-vector approaches for decades. We propose alearnable, reproducible, and reusable solution for the automatic transformation of raster maps into vector objects (building blocks, streets,rivers). It is built upon the complementary strength of mathematical morphology and convolutional neural networks through efficient edge filtering. Even more, we modify ConnNet and combine with deep edgefiltering architecture to make use of pixel connectivity information and built an end-to-end system without requiring any post-processing techniques. In this paper, we focus on the comprehensive benchmark on various architectures on multiple datasets coupled with a novel vectorization step. Our experimental results on a new public dataset using COCO Panoptic metric exhibit very encouraging results confirmedby a qualitative analysis of the success and failure cases of our approach. Code, dataset, results and extra illustrations are freely available at https://github.com/soduco/ICDAR-2021-Vectorization

This study presents systematic chemical (U, Pb, Ca, Si, Fe) mapping coupled with in situ analyses of major, minor and trace elements, U/Pb, 207Pb/206Pb, and O isotopic compositions of natural uraninites (UO2) from two samples of the high-grade uranium ore from the Cigar Lake unconformity-related uranium deposit (Athabasca Basin, Saskatchewan, Canada). The studied uraninites are characterized by major chemical and isotopic heterogeneities expressed at small scale (µm to tens of µm), from almost pristine zones to strongly altered material. The 206Pb/238U and 207Pb/235U ratios of the different areas are widely spread and depict two similar and well-defined Discordia, providing an upper intercept age of crystallization at ca. 1300 Ma (1299 ± 4 and 1308 ± 14 Ma, respectively) and lower intercepts at 38 ± 13 and 72 ± 22 Ma, respectively. The freshest areas are characterized by sub-concordant 206Pb/238U and 207Pb/235U ratios, identical chemical compositions and similar very low δ18O values (−39.3 to −31.4‰). These data indicate that the two uraninites both crystallized at ca. 1300 Ma, from the same fluid and under identical physico-chemical conditions. Alteration is characterized by (i) the progressive incorporation of Ca, Si, and Fe, reaching several wt.%, which substitute to the radiogenic Pb and cause a progressive decrease in the Pb/U isotopic ratios. The radiogenic Pb is also substituted by water during the alteration, (ii) concomitant variations in trace element contents (As, Mn, V, LREEs, Sr, Th, B, Ba, Nb, for example) and (iii) heavier δ18O signatures (−22.5 to −8.91‰), typical of meteoric waters, in the altered zones. This combined approach demonstrates that fluid-driven post-crystallization exchanges affected each uraninite during recent fluid flow events (ca. 40 Ma and 70 Ma respectively). The relatively high dispersion of the Pb/U ratios in relation to the Discordia for both samples is considered as linked to a local (nm to µm-scale) differential mobility between lead and uranium within the uranium oxides. The chemical changes affecting elements previously considered as immobile in uraninite, such as REEs, indicate that these elements are not preserved during the post-crystallization alteration process studied here. Alteration processes may therefore have a major impact on the classical geochemical tracers, such as REE patterns or LREE/HREE ratios, currently used in nuclear forensic studies. The isotopic and chemical tracers currently used to track back the origin, age and history of natural uraninites should therefore be considered with a high degree of caution to avoid misleading and erroneous conclusions. Moreover, the comparison of calculated U-Th-Pb chemical, 207Pb/206Pb, and Pb/U isotopic ages shows that the use of age clustering for determining U-Th-Pb chemical ages and 206Pb/207Pb ages is not appropriate for constraining crystallization stage(s) of altered uraninites and for deciphering the different fluid events that potentially altered or recrystallized the uraninites over time. This study also indicates that estimation of the crystallization age of uraninite from substitution trends of Pb to Ca is not applicable to unconformity-related U deposits and results in overestimated ages because of an initial integration of calcium in the uraninite lattice at the time of crystallization.

Supplementary material (code, extra figures) available at https://github.com/soduco/paper-dgmm2021/; International audience; The digitization of historical maps enables the study of ancient, fragile, unique, and hardly accessible information sources. Main map features can be retrieved and tracked through the time for subsequent thematic analysis. The goal of this work is the vectorization step, i.e., the extraction of vector shapes of the objects of interest from raster images of maps. We are particularly interested in closed shape detection such as buildings, building blocks, gardens, rivers, etc. in order to monitor their temporal evolution. Historical map images present significant pattern recognition challenges. The extraction of closed shapes by using traditional Mathematical Morphology (MM) is highly challenging due to the overlapping of multiple map features and texts. Moreover, state-of-the-art Convolutional Neural Networks (CNN) are perfectly designed for content image filtering but provide no guarantee about closed shape detection. Also, the lack of textural and color information of historical maps makes it hard for CNN to detect shapes that are represented by only their boundaries. Our contribution is a pipeline that combines the strengths of CNN (efficient edge detection and filtering) and MM (guaranteed extraction of closed shapes) in order to achieve such a task. The evaluation of our approach on a public dataset shows its effectiveness for extracting the closed boundaries of objects in historical maps.

This paper presents the final results of the ICDAR 2021 Competition on Historical Map Segmentation (MapSeg), encouraging research on a series of historical atlases of Paris, France, drawn at 1/5000 scale between 1894 and 1937. The competition featured three tasks, awarded separately. Task~1 consists in detecting building blocks and was won by the L3IRIS team using a DenseNet-121 network trained in a weakly supervised fashion. This task is evaluated on 3 large images containing hundreds of shapes to detect. Task~2 consists in segmenting map content from the larger map sheet, and was won by the UWB team using a U-Net-like FCN combined with a binarization method to increase detection edge accuracy. Task~3 consists in locating intersection points of geo-referencing lines, and was also won by the UWB team who used a dedicated pipeline combining binarization, line detection with Hough transform, candidate filtering, and template matching for intersection refinement. Tasks~2 and~3 are evaluated on 95 map sheets with complex content. Dataset, evaluation tools and results are available under permissive licensing at \url{https://icdar21-mapseg.github.io/}., Selected as one of the official competitions for the 16th International Conference on Document Analysis and Recognition (ICDAR 2021), September 5-10, 2021, Lausanne, Switzerland (https://icdar2021.org/). Extra material available at https://icdar21-mapseg.github.io/

The Galat Sufar South (GSS) gold deposit (Block 14, NE Sudan) is located within a complexly deformed zone at the junction between the Keraf Shear Zone and the Atmur-Delgo Suture, within the western portion of the Arabian-Nubian Shield (ANS). The combination of a petrographic and structural study of the gold mineralization at the GSS deposit, carried out at the μm-to tens of km-scale, allows the deciphering of the deformation history of this poorly documented area and provides insights on the geodynamic context favorable for gold mineralization in the northwesternmost Nubian Shield. Our study highlights that the GSS gold deposit recorded a polyphase deformation history dominated by an early, ductile-dominated, progressive deformation episode associated with the economic gold mineralization at GSS. It displays an atypical structural control by subvertical simple shearing evidenced by subvertical linear features (stretching lineation and potential sheath folding). The proposed multi-scale approach helps to correlate this subvertical, linear, progressive deformation event and the coeval economic gold mineralization with the early N-trending compressive tectonics related to the Atmur-Delgo suturing.

Systematically assessing the influence of new urban plans is an important challenge for designing them efficiently. In this paper, we propose a method to assess the influence of local ‘Right to Build’ regulations on constructibility. Our method is based on an optimization algorithm that generates building configurations. This method requires a geographic model that supports the formalization of the Right to Build regulation in order to check if a building respects it. The proposed approach relies on the trans-dimensional simulated annealing optimization method, which produces building configurations composed of a set of parametric objects (boxes in our implementation). Our proposition is released as the SimPLU3D Open-Source project ( http://ignf.github.io/simplu3D/ ). In this paper, we present some tests and results based on this implementation and a use related to the assistance to ‘Right to Build’ designers.

International audience; The central Keraf suture recorded complex lithospheric-scale deformation associated with the formation of the Neoproterozoic Arabian-Nubian shield and hosts the WG03, Central Zone and UTM gold deposits, Gabgaba district, northeastern Sudan. This study aims at (i) unravelling the tectonic history recorded by the central Keraf suture and (ii) interpreting the spatial and genetic relationships between structural setting and gold mineralization. To this end, we coupled field petrographic observations and structural measurements made along a 50 km-long geological cross-section through the Gabgaba district with macroscopic and microscopic description of mineralized structures. The structural setting of the central Keraf suture is dominated by progressive deformation, from ductile D1a Keraf thrusting to ductile-brittle D1b sinistral shearing in a prolonged northwest-orientated convergence regime. A first mineralization event, leading to a minor gold endowment, relates to magmatic accretion pre-dating D1a Keraf suturing. The second gold episode is characterized by ore veining as a response to progressive late collisional D1b Keraf strike-slip shearing and may be classified as orogenic gold. Most of the gold budget of the Gabgaba district formed at this stage. In summary, the central Keraf suture exemplifies that the Arabian-Nubian shield contains significant polyphase gold mineralization along lithospheric-scale structures. These structures may record a complex tectonic evolution from magmatic accretion to collision, with a strong structural control on gold endowment.

In addition to more traditional geographical data such as images (rasters) and vectors, point cloud data are becoming increasingly available. Such data are appreciated for their precision and true three-Dimensional (3D) nature. However, managing point clouds can be difficult due to scaling problems and specificities of this data type. Several methods exist but are usually fairly specialised and solve only one aspect of the management problem. In this work, we propose a comprehensive and efficient point cloud management system based on a database server that works on groups of points (patches) rather than individual points. This system is specifically designed to cover the basic needs of point cloud users: fast loading, compressed storage, powerful patch and point filtering, easy data access and exporting, and integrated processing. Moreover, the proposed system fully integrates metadata (like sensor position) and can conjointly use point clouds with other geospatial data, such as images, vectors, topology and other point clouds. Point cloud (parallel) processing can be done in-base with fast prototyping capabilities. Lastly, the system is built on open source technologies; therefore it can be easily extended and customised. We test the proposed system with several billion points obtained from Lidar (aerial and terrestrial) and stereo-vision. We demonstrate loading speeds in the ∼ 50 million pts/h per process range, transparent-for-user and greater than 2 to 4:1 compression ratio, patch filtering in the 0.1 to 1 s range, and output in the 0.1 million pts/s per process range, along with classical processing methods, such as object detection.

International audience; OpenMOLE (Reuillon et al., 2013) est une plateforme d’exploration automatique de modèles numériques. Elle permet d’étudier des programmes développés dans une très large gamme de langages. OpenMOLE permet aussi de distribuer la charge de calcul sur la plupart des environnements de calcul (serveur, clusters, grille de calcul, cloud). La description de ces expériences sont décrits à l’aide DSL à destination d’utilisateurs non-informaticiens et non-spécialistes des environnements HPC. Alors que cette plateforme fête sa 10ème release salué par une communauté d’utilisateur en forte croissance, un nouveau pas vient d’être franchi avec l’organisation en 2019 d’une première école d’été dédiée à “l’exploration de modèles”. Durant la formation, la plateforme et l’écosystème de méthodes d’exploration qui l’accompagne sont utilisés de manière intensive. Les travaux pratiques mettent en oeuvre l’exploration d’un modèle “jouet” de dynamiques complexes développé pour l’occasion. Il s’agit d’un modèle multi-agent spatialisé de type proie/prédateur sur la thématique des zombies. Les apprenants pourront découvrir l’usage et la spécificité de chacune des méthodes d’explorations intégrés dans la plateforme de façon interactive : analyses de sensibilité (Saltelli, Morris), calibrage et optimisation (Profiles, NSGA2, ABC), diversité (PSE). Lors des deux derniers jours, les participants sont invités à formuler des questions sur le modèle de Zombies et à en proposer une étude en utilisant les outils découverts les jours précédents. La mise en oeuvre rapide de ces méthodes n’étant possible qu’avec l’appui d’un environnement HPC, un partenariat avec l’UMR IDEES et le méso-centre Normand du CRIANN a été mis en place pour assurer un accès rapide aux ressources de calcul nécessaires (1000 coeurs / 25 participants) pour les explorations menées pendant les 5 jours d’école. Développé avant tout pour accéder à des ressources de type grille, OpenMOLE s’est constamment adapté pour offrir des connecteurs capable de suivre l’offre croissante et très diversifiée en environnements de calcul. Il s’agit d’ajouter à la fois des nouveaux connecteurs (PBS, SLURM, etc.) mais aussi de nouveaux moyens d’encapsulation et de déploiement des programmes utilisateurs (Kubernetes, UDocker, PRoot, etc.). La collaboration entre les deux équipes du CRIANN et d’OpenMOLE s’inscrit dans ce cadre. Bénéfique pour les deux parties, elle a permis de soulever et résoudre des points de blocages représentatifs des diversités de pratiques qui peuvent exister sur le plan matériel et logiciels (Fortran/C vs Java/R/Python) entre les deux communautés (Grille / Cluster). Dans cette présentation nous proposons de faire une synthèse des résultats obtenus par les groupes sur le modèle jouet, ainsi qu’un retour sur cette collaboration originale entre les deux équipes techniques d’OpenMOLE et du CRIANN.Reuillon, R., Leclaire, M., and Rey-Coyrehourcq, S. (2013). Openmole, a workflow engine specifically tailored for the distributed exploration of simulation models. Future Generation Computer Systems, 29(8):1981–1990.

Antique maps are full of engraved geohistorical features. They provide representations of past states of the geographical space and are favored by historians and social scientists for their uniqueness and coherence. Working on a GIS dedicated to the history of the French territory, we extracted spatial information from the Cassini Carte de France (full name Carte Générale & Particulière de la France) as vector data. Based on the first geodetic survey of France [1, 4], this well-known and monumental map has been drawn on 182 paper sheets of size 610 × 955 mm at the scale of 1:86,400 or 1 line for 100~toises (1 inch to 1.36 miles). It depicts the French territory with fine-grained information about populated and named places, settlements, landscape features, hydrographic, ecclesiastical and road networks [3, 5, 6, 7]. As a case study, the sheet numbered 52 provided more than 6 800 spatial footprints that we have stored as a geographic database. Following the distinction made by Cassini himself between “geometric” and “topographic” entities, our geographical database is composed of two families of data, namely Triangulated Geographical Entities (“geometric” entities in Cassini’s own terms) whose geodetic properties are partly documented and Relative Geographical Entities (“topographic” in Cassini’s terms) which are dependent on and located relative to the former (Fig. 1). Those entities are analytically distinct but come together from a single artifact: the primary source they are engraved in during the mapmaking process. Because this process of embeddedness is not fully documented, retrieving both classes of entities called for a cautious cartographic visualisation with similar semiological rules and aesthetics as the original historical map (Fig. 2). This “Cassini map style” preserves the cartographic properties of the geohistorical data extracted from this primary source: generalisation, scale, spatial granularity and the overall intentions of the mapmakers [2]. Often neglected, such properties are constitutive components and dimensions of the mapping style which forms the context and gives crucial information on the accuracy and the relationships between geo-historical data enclosed in. Our poster provides a renewed cartographic visualisation of the sheet 52nd sheet of the Carte de France, centred on the french cities of Clermont, Riom and Thiers. It reveals unnoticed cartographic entities that were hardly legible in the original map. The historiography of cartography has been largely, and for a long time, based on critical edition of old maps published as non-georeferenced facsimile . We propose to renew this approach by producing digital maps from vector geographic databases that combine the aesthetics and semiology of old map styles with the modelling capabilities of modern GIS.

National audience; Dans cette présentation, nous décrivons les motivations et les résultats liés à la construction d'un modèle multi-agents pour étudier les effets de la ségrégation sur la dynamique des inégalités sociales dans les comportements alimentaires. Ce travail est issu d'un effort de groupe au sein d'un réseau interdisciplinaire de jeunes chercheurs sur les systèmes urbains complexes (EIGHTIES). Nous partons du constat que l'espace urbain (et francilien en particulier) est ségrégé socialement lorsqu’on l’observe à partir des lieux de résidence (Préteceille, 2006) mais aussi à partir des lieux du quotidien (Le Roux et al., 2017). La mobilité quotidienne des uns et l'immobilité des autres impliquent que tous les mécanismes expliquant les inégalités sociales de santé et d'alimentation par des processus locaux - ainsi que les politiques publiques qui visent à les réduire (Vallée, 2017) - doivent être envisagés dans le temps et dans l'espace.Nous présentons un modèle multi-agents initialisé sur une population synthétique de 8 millions d'agents de plus de 16 ans avec une structure démographique (sexe et âge) et sociale (niveau d’éducation) correspondant à celle de l'Ile-de-France. Ces agents sont localisés dans l’espace francilien (divisé en 8540 cellules d’1km de côté) et dans le temps (divisé en trois plages horaire – nuit, journée, soirée) à partir du recensement de 2012 et de l’Enquête Globale Transport (EGT 2010). Chaque agent est initialement doté d’une opinion (l’importance accordée au fait de consommer "5 fruits et légumes par jour") et d’un comportement (le fait de consommer ou non au moins 5 fruits et légumes par jour) sur la base de leur groupe sociodémographique à partir des données du Baromètre Santé Nutrition de 2002 (Santé Publique France). Le cœur du modèle se compose de deux mécanismes concurrents et complémentaires de changement d'opinion lié (i) à l’écart d’opinion entre deux individus en coprésence et (ii) à l'observation des comportements alimentaires des voisins de la même cellule. Le passage entre l’opinion et le changement de comportement est médié par un mécanisme d'inertie et par des contraintes (liées à l'argent, au temps et aux habitudes alimentaires de la famille). Nous modélisons aussi le fait qu'un changement dans le sens préconisé par les agences de santé a un effet gratifiant pour l'individu (e.g. une opinion positive renforcée à l'égard de ce régime alimentaire). A partir des changements de comportement observés entre les Baromètres Santé Nutrition de 2002 et de 2008, ce modèle est calibré, évalué et exploré en utilisant du calcul distribué via la plateforme OpenMole (Reuillon et al., 2013).Indifféremment des paramètres généraux du modèle, nous montrons que les inégalités sociales de comportements alimentaires sont accrues lorsque la ségrégation sociale est forte à la fois la nuit et le jour, puisque certains individus non mobiles ne sont pas mis en coprésence avec des individus présentant d'autres opinions et comportements. De même, on observe que la ségrégation diurne renforce l'effet de la ségrégation nocturne, puisque le brassage des populations n'est pas aléatoire mais est socialement différencié.--Le Roux G., Vallée J., Commenges H. (2017). Social segregation around the clock in the Paris region (France). Journal of Transport Geography, 59, 134-145.Préteceille E. (2006). La ségrégation sociale a-t-elle augmenté? Sociétés contemporaines, (2), 69-93.Reuillon R., Leclaire M., Rey-Coyrehourcq S. (2013). OpenMOLE, a workflow engine specifically tailored for the distributed exploration of simulation models. Future Generation Computer Systems, 29(8), 1981-1990.Vallée J. (2017). Challenges in targeting areas for public action. Target areas at the right place and at the right time. Journal of Epidemiology and Community Health. Vol 71 No 10, 945-946.

The latest developments in the field of digital humanities have increasingly enabled the construction of large data sets which can be easily accessed and used. These data sets often contain indirect spatial information, such as historical addresses. Historical geocoding is the process of transforming indirect spatial information into direct locations which can be placed on a map, thus allowing for spatial analysis and cross-referencing. There are many geocoders that work efficiently for current addresses. However, these do not tackle temporal information, and usually follow a strict hierarchy (country, city, street, house number, etc.) which is difficult&mdash, if not impossible&mdash, to use with historical data. Historical data is filled with uncertainty (pertaining to temporal, textual, and positional accuracy, as well as to the reliability of historical sources) which can neither be ignored nor entirely resolved. Our open source, open data, and extensible solution for geocoding is based on extracting a large number of simple gazetteers composed of geohistorical objects, from historical maps. Geocoding a historical address becomes the process of finding one or several geohistorical objects in the gazetteers which best match the historical address searched by the user. The matching criteria are customisable, weighted, and include several dimensions (fuzzy string, fuzzy temporal, level of detail, positional accuracy). Since our goal is to facilitate historical work, we also put forward web-based user interfaces which help geocode (one address or batch mode) and display results over current or historical maps. Geocoded results can then be checked and edited collaboratively (no source is modified). The system was tested on the city of Paris, France, for the 19th and 20th centuries. It showed high response rates and worked quickly enough to be used interactively.

International audience; Evidence suggests that socioeconomic profile and social interactions with neighbours affect health behaviours. Social interactions result from the way individuals are spatially distributed in the city (i.e. the level of segregation) not only at their residences but also at their daily activities/locations. In order to evaluate the impact of social segregation " around the clock " on health behaviours, we present a data-driven agent-based model of dietary dynamics in the Paris Region. The model includes a mechanism which puts agents in interaction, a mechanism of opinion diffusion and a mechanism of behaviour change under constraint. From a synthetic representative population of 8 million agents, we combine two scenarios of agents' residential location (random location and census-based location) and two scenarios of agents' daily activities location (random location and survey-based location). With these four scenarios , we aim to compare the impact of the spatiotemporal representation of territories (and the related social interactions) on the outputs of a simulation model of dietary dynamics.; Les comportements de santé des individus dépendent étroitement de leur statut socio-économique et des interactions sociales qu'ils peuvent avoir avec leur entourage. Ces interactions résultent de la ségrégation à l’œuvre dans l'ensemble des quartiers qu'ils fréquentent au quotidien. Afin d'évaluer l'impact de la ségrégation sociale tout au long de la journée sur les comportements de santé, nous proposons un modèle multi-agents des dynamiques de comportements alimentaires en Île-de-France basé sur des données empiriques. Le modèle comprend un mécanisme de mise en interaction, de diffusion d'opinion et de changement de comportement sous contrainte. À partir d'une population synthétique de 8 millions d'agents, nous combinons deux scénarios de localisation résidentielle des agents (aléatoire et observée) et deux scénarios de localisation des lieux quotidiens d'activité (aléatoire et observée) afin de comparer l'impact des représentations spatio-temporelles des territoires (et des interactions sociales associées) sur nos modèles de simulation de la dynamique des comportements alimentaires.

In addition to the traditional Geographic Information System (GIS) data such as images and vectors, point cloud data has become more available. It is appreciated for its precision and true three-Dimensional (3D) nature. However, managing the point cloud can be difficult due to scaling problems and specificities of this data type. Several methods exist but are usually fairly specialised and solve only one aspect of the management problem. In this work, we propose a complete and efficient point cloud management system based on a database server that works on groups of points rather than individual points. This system is specifically designed to solve all the needs of point cloud users: fast loading, compressed storage, powerful filtering, easy data access and exporting, and integrated processing. Moreover, the system fully integrates metadata (like sensor position) and can conjointly use point clouds with images, vectors, and other point clouds. The system also offers in-base processing for easy prototyping and parallel processing and can scale well. Lastly, the system is built on open source technologies; therefore it can be easily extended and customised. We test the system will several billion points of point clouds from Lidar (aerial and terrestrial ) and stereo-vision. We demonstrate ~ 400 million pts/h loading speed, user-transparent greater than 2 to 4:1 compression ratio, filtering in the approximately 50 ms range, and output of about a million pts/s, along with classical processing, such as object detection.

Streets are large, diverse, and used for conflicting transport modalities as well as social and cultural activities. Proper planning is essential and requires data. Manually fabricating data that represent streets (street reconstruction) is error-prone and time consuming. Automatising street reconstruction is a challenge because of the diversity, size, and scale of the details (~ cm for cornerstone) required. The state-of-the-art focuses on roads and is strongly oriented by each application (simulation, visualisation, planning). We propose a unified framework that works on real Geographic Information System (GIS) data and uses a strong, yet simple hypothesis when possible to produce coherent street modelling at the city scale or street scale. Because it is updated only locally in subsequent computing, the result can be improved by adapting input data and the parameters of the model. We reconstruct the entire Paris streets in a few minutes and show how the results can be edited simultaneously by several concurrent users.

This paper is an output of a French national project called iSpace&Time aiming to provide a 4 dimensional platform of an urban dynamics. In order to express the urban traffic, we took an advantage of the mobile phone data to investigate the behavior of the origin destination flow within the Paris and its suburb aiming to explore the different mode of the transportation. Indeed the spatiotemporal heterogeneities of mobile phone data make the task of mode of transportation separation very challenging, sometimes even impossible. Thus, by exploring the OD matrix in order to revealing any probable continues trends or any dominant trace of the flow stating a specific mode of transportation, the commuter trains happened to be somehow detectable. Then an individual-based step-by-step approach is proposed to estimate mode of transportation from mobile phone data. Analyzing the individual trajectory, the decision is given to a segment level with respect to different measures. An early promising outcome consists of detection of the segments in which people would take the metro.

International audience; Cet article présente l'utilisation de méthodes de distribution des calculs de simulation et d'exploration de modèles de simulation de la plateforme OpenMOLE appliquées à un modèle de simulation de droits à bâtir: SimPLU3D. Cet outil simule la construction et le placement de formes bâties à l'échelle de la parcelle en respectant les règles contenues dans un Plan Local d'Urbanisme. La plateforme d'exploration de modèles OpenMOLE a été mobilisée pour deux expérimentations : la distribution du calcul des formes bâties par îlot morphologique à l'échelle de tout un département, et l'exploration de la diversité des formes bâties qu'autorise un PLU pour un îlot urbain d'une vingtaine de parcelles, au moyen de la méthode PSE (Pattern Space Exploration). La mobilisation d'infrastructures de calcul distribué et la parallélisation du calcul coordonnée par OpenMOLE a permis d'obtenir ces résultats en un temps raisonnable. Les premiers résultats présentés sont encourageants et ouvrent des perspectives d'expérimentation opérationnelle à destination d'utilisateurs (aménageurs, élus, etc.).

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National audience

Various aspects of intrinsic motivation have long been theorized as key determinants of learning achievement. The present research seeks deeper insights into these intrinsically motivating mechanisms by investigating neurophysiological correlates of cognitive absorption in the context of enactive learning, specifically simulation-based training on the use of enterprise resource planning (ERP) software. An experiment was conducted in which 36 student trainees used ERP software to make decisions while running a simulated company. Consistent with flow theory, skill, difficulty, and their interaction significantly influenced cognitive absorption (R2 = .16). Five neurophysiological measures were captured for each trainee: EEG alpha, EEG beta, electrodermal activity (EDA), heart rate, and heart rate variability. Each of the five neurophysiological measures explained significant unique variance in cognitive absorption over and above skill, difficulty, and their interaction, and collectively more than doubled the explained variance to R2 = .34. Overall, cognitive absorption was positively related to a more relaxed, less vigilant state. Cognitive absorption was significantly related to the training outcome. These findings provide new insights into the psychological states that are conducive to experiencing cognitive absorption during enactive training.

Cities are complex systems shaped by dynamics operating at different scales. As an interdisciplinary researcher in geographical information sciences, I work together with transport, geography, urban planning, history, demography and physics specialists, in order to propose better tools, models and data for the multi-scale study of urban dynamics. I present my contributions by order of scale, from the largest to the smallest:the very large scale for questions relating to mobility, the large scale for those relating to urban planning and the small scale for questions about territorial evolutions. For each part, I propose a common progress: first, questions about information sources, knowledge representation and manipulation, their storage; then, data analysis, their enrichment and matching ; finally, the interaction with these data, their visualisation, their interpretation, their validation and their correction by users., La ville est un système complexe façonné par des dynamiques opérant à des échelles différentes. En tant que chercheur en sciences de l’information géographique travaillant dans l’interdisciplinarité, je travaille en collaboration avec des spécialistes du transport, des géographes, des urbanistes, des historiens, des démographes, et des physiciens, afin de proposer de meilleurs outils, modèles et données pour l’étude multi-échelle des dynamiques urbaines. Je présente mes contribution dans un ordre correspondant à l’échelle spatiale, de la plus large à la plus fine : la très grande échelle pour les questions liées à la mobilité, la grande échelle pour celles liées à l’urbanisme et la petite échelle pour les questions liées à l’évolution du territoire dans le temps long. Pour chaque partie, je propose un cheminement commun : tout d’abord la question des sources d’information, des connaissances manipulées, leur représentation, leur stockage ; ensuite, la question de l’analyse de ces données, de leur enrichissement, de leur croisement ; enfin, l’interaction avec ces données, leur visualisation, leur interprétation, leur validation, leur correction par des utilisateurs.

International audience; The design of documents impacting potential new constructions, such as Right to Build plans, is a complex issue. New tools need to be proposed in order to systematically assess the impact of regulations on the building potential of the concerned areas. Furthermore, it is often not directly the morphology of new constructions that administrations and citizens would like to regulate but their properties with regard to other phenomena (solar energy potential, etc.). In order to tackle these issues, we propose in this article to explore building configurations and regulations using a stochastic building generator and a workflow engine. The workflow we propose for such an exploration will produce important amounts of data that we intend to release as OpenData in order for administrations, urban planners and citizens to be able to freely visualize and collectively choose the regulations that best suit their territory. Such amount of 3D geographical data also suggests new issues in geovisualization.

Morphological analysis of urban fabric is a relevant step in order to perform the analysis of urban dynamics and to simulate their evolutions. In this context, the objective of this paper is to test to test two relational data mining methods (Cardinalisation and Quantiles) to label urban blocks and to produce rules on their morphology. The objective is to automate the identification of urban fabrics from vector and historical database and to extract knowledge on urban morphology. Several tests applied on the Strasbourg area on historical database, are encouraging (80% of global accuracy on historical database). From the classification results, a statistical analysis of evolutions is described. MOTS-CLES : tissu urbain, morphologie, bases de donnees vectorielles, classification, arbre de decision, evolution.

The approach presented in this paper uses a multi-agent system to model the self- organising properties of urban systems from a morphological point of view and aims at provid- ing a tool to study urban growth. The proposed multi-agent system is a hierarchy of topographic agents (e.g. buildings, roads, rivers or urban blocks) that are built, modified, merged, split, re- structured and destroyed over time. Each agent's behaviour is controlled by a set of evolution rules, constraints and associated actions. This paper deals especially with populating functions which allow the creation of new agents while respecting a certain spatial organisation and a certain construction process.

This article presents the use of 3D GIS to represent, analyze and explore the most common urban rules of constructability found in French local urban planning regulations. A model is proposed in order to allow the capture and the management of urban rules. In this article, the exploration of these rules is made in 3D GIS through three different functions: check-up of these rules on a parcel, visualization of volume generated by a set of rules and generation under constraints of a building shape regarding to this volume. Thus, this tool offers the possibility to link parameters of urban rules to their impact on morphology of buildings. MOTS-CLES : SIG 3D, regles d'urbanisme, analyse spatiale, geovisualisation