6 research outputs found

    A multi-agent system for on-the-fly web map generation and spatial conflict resolution

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    Résumé Internet est devenu un moyen de diffusion de l’information géographique par excellence. Il offre de plus en plus de services cartographiques accessibles par des milliers d’internautes à travers le monde. Cependant, la qualité de ces services doit être améliorée, principalement en matière de personnalisation. A cette fin, il est important que la carte générée corresponde autant que possible aux besoins, aux préférences et au contexte de l’utilisateur. Ce but peut être atteint en appliquant les transformations appropriées, en temps réel, aux objets de l’espace à chaque cycle de génération de la carte. L’un des défis majeurs de la génération d’une carte à la volée est la résolution des conflits spatiaux qui apparaissent entre les objets, essentiellement à cause de l’espace réduit des écrans d’affichage. Dans cette thèse, nous proposons une nouvelle approche basée sur la mise en œuvre d’un système multiagent pour la génération à la volée des cartes et la résolution des conflits spatiaux. Cette approche est basée sur l’utilisation de la représentation multiple et la généralisation cartographique. Elle résout les conflits spatiaux et génère les cartes demandées selon une stratégie innovatrice : la génération progressive des cartes par couches d’intérêt. Chaque couche d’intérêt contient tous les objets ayant le même degré d’importance pour l’utilisateur. Ce contenu est déterminé à la volée au début du processus de génération de la carte demandée. Notre approche multiagent génère et transfère cette carte suivant un mode parallèle. En effet, une fois une couche d’intérêt générée, elle est transmise à l’utilisateur. Dans le but de résoudre les conflits spatiaux, et par la même occasion générer la carte demandée, nous affectons un agent logiciel à chaque objet de l’espace. Les agents entrent ensuite en compétition pour l’occupation de l’espace disponible. Cette compétition est basée sur un ensemble de priorités qui correspondent aux différents degrés d’importance des objets pour l’utilisateur. Durant la résolution des conflits, les agents prennent en considération les besoins et les préférences de l’utilisateur afin d’améliorer la personnalisation de la carte. Ils améliorent la lisibilité des objets importants et utilisent des symboles qui pourraient aider l’utilisateur à mieux comprendre l’espace géographique. Le processus de génération de la carte peut être interrompu en tout temps par l’utilisateur lorsque les données déjà transmises répondent à ses besoins. Dans ce cas, son temps d’attente est réduit, étant donné qu’il n’a pas à attendre la génération du reste de la carte. Afin d’illustrer notre approche, nous l’appliquons au contexte de la cartographie sur le web ainsi qu’au contexte de la cartographie mobile. Dans ces deux contextes, nous catégorisons nos données, qui concernent la ville de Québec, en quatre couches d’intérêt contenant les objets explicitement demandés par l’utilisateur, les objets repères, le réseau routier et les objets ordinaires qui n’ont aucune importance particulière pour l’utilisateur. Notre système multiagent vise à résoudre certains problèmes liés à la génération à la volée des cartes web. Ces problèmes sont les suivants : 1. Comment adapter le contenu des cartes, à la volée, aux besoins des utilisateurs ? 2. Comment résoudre les conflits spatiaux de manière à améliorer la lisibilité de la carte tout en prenant en considération les besoins de l’utilisateur ? 3. Comment accélérer la génération et le transfert des données aux utilisateurs ? Les principales contributions de cette thèse sont : 1. La résolution des conflits spatiaux en utilisant les systèmes multiagent, la généralisation cartographique et la représentation multiple. 2. La génération des cartes dans un contexte web et dans un contexte mobile, à la volée, en utilisant les systèmes multiagent, la généralisation cartographique et la représentation multiple. 3. L’adaptation des contenus des cartes, en temps réel, aux besoins de l’utilisateur à la source (durant la première génération de la carte). 4. Une nouvelle modélisation de l’espace géographique basée sur une architecture multi-couches du système multiagent. 5. Une approche de génération progressive des cartes basée sur les couches d’intérêt. 6. La génération et le transfert, en parallèle, des cartes aux utilisateurs, dans les contextes web et mobile.Abstract Internet is a fast growing medium to get and disseminate geospatial information. It provides more and more web mapping services accessible by thousands of users worldwide. However, the quality of these services needs to be improved, especially in term of personalization. In order to increase map flexibility, it is important that the map corresponds as much as possible to the user’s needs, preferences and context. This may be possible by applying the suitable transformations, in real-time, to spatial objects at each map generation cycle. An underlying challenge of such on-the-fly map generation is to solve spatial conflicts that may appear between objects especially due to lack of space on display screens. In this dissertation, we propose a multiagent-based approach to address the problems of on-the-fly web map generation and spatial conflict resolution. The approach is based upon the use of multiple representation and cartographic generalization. It solves conflicts and generates maps according to our innovative progressive map generation by layers of interest approach. A layer of interest contains objects that have the same importance to the user. This content, which depends on the user’s needs and the map’s context of use, is determined on-the-fly. Our multiagent-based approach generates and transfers data of the required map in parallel. As soon as a given layer of interest is generated, it is transmitted to the user. In order to generate a given map and solve spatial conflicts, we assign a software agent to every spatial object. Then, the agents compete for space occupation. This competition is driven by a set of priorities corresponding to the importance of objects for the user. During processing, agents take into account users’ needs and preferences in order to improve the personalization of the final map. They emphasize important objects by improving their legibility and using symbols in order to help the user to better understand the geographic space. Since the user can stop the map generation process whenever he finds the required information from the amount of data already transferred, his waiting delays are reduced. In order to illustrate our approach, we apply it to the context of tourist web and mobile mapping applications. In these contexts, we propose to categorize data into four layers of interest containing: explicitly required objects, landmark objects, road network and ordinary objects which do not have any specific importance for the user. In this dissertation, our multiagent system aims at solving the following problems related to on-the-fly web mapping applications: 1. How can we adapt the contents of maps to users’ needs on-the-fly? 2. How can we solve spatial conflicts in order to improve the legibility of maps while taking into account users’ needs? 3. How can we speed up data generation and transfer to users? The main contributions of this thesis are: 1. The resolution of spatial conflicts using multiagent systems, cartographic generalization and multiple representation. 2. The generation of web and mobile maps, on-the-fly, using multiagent systems, cartographic generalization and multiple representation. 3. The real-time adaptation of maps’ contents to users’ needs at the source (during the first generation of the map). 4. A new modeling of the geographic space based upon a multi-layers multiagent system architecture. 5. A progressive map generation approach by layers of interest. 6. The generation and transfer of web and mobile maps at the same time to users

    Global Dynamics of the Offshore Wind Energy Sector Derived from Earth Observation Data - Deep Learning Based Object Detection Optimised with Synthetic Training Data for Offshore Wind Energy Infrastructure Extraction from Sentinel-1 Imagery

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    The expansion of renewable energies is being driven by the gradual phaseout of fossil fuels in order to reduce greenhouse gas emissions, the steadily increasing demand for energy and, more recently, by geopolitical events. The offshore wind energy sector is on the verge of a massive expansion in Europe, the United Kingdom, China, but also in the USA, South Korea and Vietnam. Accordingly, the largest marine infrastructure projects to date will be carried out in the upcoming decades, with thousands of offshore wind turbines being installed. In order to accompany this process globally and to provide a database for research, development and monitoring, this dissertation presents a deep learning-based approach for object detection that enables the derivation of spatiotemporal developments of offshore wind energy infrastructures from satellite-based radar data of the Sentinel-1 mission. For training the deep learning models for offshore wind energy infrastructure detection, an approach is presented that makes it possible to synthetically generate remote sensing data and the necessary annotation for the supervised deep learning process. In this synthetic data generation process, expert knowledge about image content and sensor acquisition techniques is made machine-readable. Finally, extensive and highly variable training data sets are generated from this knowledge representation, with which deep learning models can learn to detect objects in real-world satellite data. The method for the synthetic generation of training data based on expert knowledge offers great potential for deep learning in Earth observation. Applications of deep learning based methods can be developed and tested faster with this procedure. Furthermore, the synthetically generated and thus controllable training data offer the possibility to interpret the learning process of the optimised deep learning models. The method developed in this dissertation to create synthetic remote sensing training data was finally used to optimise deep learning models for the global detection of offshore wind energy infrastructure. For this purpose, images of the entire global coastline from ESA's Sentinel-1 radar mission were evaluated. The derived data set includes over 9,941 objects, which distinguish offshore wind turbines, transformer stations and offshore wind energy infrastructures under construction from each other. In addition to this spatial detection, a quarterly time series from July 2016 to June 2021 was derived for all objects. This time series reveals the start of construction, the construction phase and the time of completion with subsequent operation for each object. The derived offshore wind energy infrastructure data set provides the basis for an analysis of the development of the offshore wind energy sector from July 2016 to June 2021. For this analysis, further attributes of the detected offshore wind turbines were derived. The most important of these are the height and installed capacity of a turbine. The turbine height was calculated by a radargrammetric analysis of the previously detected Sentinel-1 signal and then used to statistically model the installed capacity. The results show that in June 2021, 8,885 offshore wind turbines with a total capacity of 40.6~GW were installed worldwide. The largest installed capacities are in the EU (15.2~GW), China (14.1~GW) and the United Kingdom (10.7~GW). From July 2016 to June 2021, China has expanded 13~GW of offshore wind energy infrastructure. The EU has installed 8~GW and the UK 5.8~GW of offshore wind energy infrastructure in the same period. This temporal analysis shows that China was the main driver of the expansion of the offshore wind energy sector in the period under investigation. The derived data set for the description of the offshore wind energy sector was made publicly available. It is thus freely accessible to all decision-makers and stakeholders involved in the development of offshore wind energy projects. Especially in the scientific context, it serves as a database that enables a wide range of investigations. Research questions regarding offshore wind turbines themselves as well as the influence of the expansion in the coming decades can be investigated. This supports the imminent and urgently needed expansion of offshore wind energy in order to promote sustainable expansion in addition to the expansion targets that have been set

    OGRS2012 Symposium Proceedings

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    Do you remember the Open Source Geospatial Research and Education Symposium (OGRS) in Nantes? "Les Machines de l’Île", the Big Elephant, the "Storm Boat" with Claramunt, Petit et al. (2009), and "le Biniou et la Bombarde"? A second edition of OGRS was promised, and that promise is now fulfilled in OGRS 2012, Yverdon-les-Bains, Switzerland, October 24-26, 2012. OGRS is a meeting dedicated to sharing knowledge, new solutions, methods, practices, ideas and trends in the field of geospatial information through the development and the use of free and open source software in both research and education. In recent years, the development of geospatial free and open source software (GFOSS) has breathed new life into the geospatial domain. GFOSS has been extensively promoted by FOSS4G events, which evolved from meetings which gathered together interested GFOSS development communities to a standard business conference. More in line with the academic side of the FOSS4G conferences, OGRS is a rather neutral forum whose goal is to assemble a community whose main concern is to find new solutions by sharing knowledge and methods free of software license limits. This is why OGRS is primarily concerned with the academic world, though it also involves public institutions, organizations and companies interested in geospatial innovation. This symposium is therefore not an exhibition for presenting existing industrial software solutions, but an event we hope will act as a catalyst for research and innovation and new collaborations between research teams, public agencies and industries. An educational aspect has recently been added to the content of the symposium. This important addition examines the knowledge triangle - research, education, and innovation - through the lens of how open source methods can improve education efficiency. Based on their experience, OGRS contributors bring to the table ideas on how open source training is likely to offer pedagogical advantages to equip students with the skills and knowledge necessary to succeed in tomorrow’s geospatial labor market. OGRS brings together a large collection of current innovative research projects from around the world, with the goal of examining how research uses and contributes to open source initiatives. By presenting their research, OGRS contributors shed light on how the open-source approach impacts research, and vice-versa. The organizers of the symposium wish to demonstrate how the use and development of open source software strengthen education, research and innovation in geospatial fields. To support this approach, the present proceedings propose thirty short papers grouped under the following thematic headings: Education, Earth Science & Landscape, Data, Remote Sensing, Spatial Analysis, Urban Simulation and Tools. These papers are preceded by the contributions of the four keynote speakers: Prof Helena Mitasova, Dr Gérard Hégron, Prof Sergio Rey and Prof Robert Weibel, who share their expertise in research and education in order to highlight the decisive advantages of openness over the limits imposed by the closed-source license system

    Usabilidade pedagógica: um fator determinante na adoção do e-Learning no ensino superior

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    O artigo que apresentamos neste simpósio doutoral surge no âmbito do Curso de Doutoramento em Educação, especialidade em Tecnologias de Informação e Comunicação na Educação, do Instituto de Educação da Universidade de Lisboa. O estudo tem como objetivo principal propor e testar um modelo que permita explicar a intenção comportamental dos docentes do Ensino Superior aquando da adoção e uso continuado das plataformas de e-Learning. Para o efeito procura-se compreender o contributo da usabilidade pedagógica como fator determinante no processo de adoção da tecnologia

    Multimetal smithing : An urban craft in rural settings?

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    Multimetal smithing should be defined as the use of more than one metal and/or different metalworking techniques within thesame crafts-milieu. This complex metalworking has long been linked to centrality, central places and urbanity in Scandinavia.It has been extensively argued that fine casting and smithing, as well as manufacture utilizing precious metals was exclusivelyundertaken within early urban settings or the “central places” pre-dating these. Furthermore, the presence of complex metalcraftsmanship has been used as a driving indicator of the political, social and economic superiority of certain sites, therebyenhancing their identity as “centralities”.Recent research has come to challenge the universality of this link between urbanity, centrality and complex metalworkingas sites in rural settings with evidence of multimetal smithing are being identified. This shows that the relationship between thecraft and centrality (urbanity) must be nuanced and that perhaps multimetal craftsmanship should be reconsidered as an urbanindicator.The thesis project “From Crucible and onto Anvil” started in 2015 and focuses on sites housing remains of multimetalcraftsmanship dating primarily from 500-1000 AD. Within the project a comprehensive survey of sites will be used to evaluate thepresence of multimetal craftsmanship in the landscape. Sites in selected target areas will also be subject to intra-site analysisfocusing on workshop organisation, production output, metalworking techniques and chronological variances.A key aim in the project is to elucidate the conceptual aspects of complex metalworking. The term multimetality is used toanalytically frame all the societal and economic aspects of multimetal craftsmanship. Through this inclusive perspective both thecraftsmanship and the metalworkers behind it are positioned within the overall socioeconomic framework. The metalworkers,their skills and competences as well as the products of their labour are viewed as dynamic actors in the landscape and on thearenas of political economy of the Late Iron Age.The survey has already revealed interesting aspects concerning multimetal smithing and urbanity. Although the multimetalsites do cluster against areas of early urban development there are also other patterns emerging. Multimetal craftsmanship – both as practice and concept – was well represented in both rural peripheral settings and urban crafts-milieus. This means that therole of multimetality as part of an “urban conceptual package” is crucial to investigate. Such an approach will have the dual endsof properly understanding the craft and its societal implications, but also further the knowledge of the phenomenon of urbanityas a whole. Was multimetal smithing part of an “urban package” that spread into the rural landscape? Did the multimetality differbetween urban and rural crafts-milieus? How does early urbanity relate to the chronology of multimetal craftsmanship?This paper aims to counter these questions using examples from the survey of multimetal sites conducted within the thesisproject. A comparison between selected sites will be presented. The purpose of this is to evaluate the role of multimetality withinthe “urban package” and discuss the role of complex metalworking in the establishment of urban arenas of interaction in LateIron Age Scandinavia
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