427 research outputs found

    Knowledge Discovery in Smart City Digital Twins

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    Despite the abundance of available urban data and the potential for reaching enhanced capabilities in the decision-making and management of city infrastructure, current data-driven approaches to knowledge discovery from city data often lack the capacity for collective data exploitation. Loosely defined data interpretation components, or disciplinary isolated interpretations of specific datasets make it easy to overlook necessary domain expertise, often resulting in speculative decision-making. Smart City Digital Twins are designed to overcome this barrier by integrating a more holistic analytics and visualization approach into the real-time knowledge discovery process from heterogeneous city data. Here, we present a spatiotemporal knowledge discovery framework for the collective exploitation of city data in smart city digital twins that incorporates both social and sensor data, and enables insights from human cognition. This is an initial step towards leveraging heterogeneous city data for digital twin-based decision-making

    Acesso multimodal a vídeos georreferenciados através da forma, velocidade e tempo em dispositivos móveis

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    Tese de mestrado, Informática, Universidade de Lisboa, Faculdade de Ciências, 2014Um volume crescente de vídeo digital é acedido, capturado e publicado diariamente na Web, a partir de diferentes plataformas e dispositivos, que cada vez mais podem georreferenciar a informação que capturam e acedem, permitindo enriquecer a sua contextualização. No entanto, a procura de vídeo tem sido limitada a palavras-chave ou a conjuntos de parâmetros, dando um suporte limitado às dimensões espacial e temporal. Os dispositivos móveis são atualmente usados de forma generalizada e estão cada vez mais a incorporar um amplo conjunto de sensores e actuadores com o potencial de capturar e apresentar vídeo em 360º e os seus metadados, tendo a capacidade de suportar experiências de utilizador mais poderosas e imersivas com vídeo. Propomos formas inovadoras de procurar, navegar e visualizar vídeo, tirando partido do potencial dos sensores e interfaces móveis nas dimensões espacial e temporal. Este trabalho foi desenvolvido no contexto do projeto de investigação ImTV, e explora modalidades inovadoras para procurar e aceder a vídeos georeferenciados, onde as dimensões espacio-temporais são de importância central, especialmente através da forma e velocidade das trajectórias dos vídeos, e do tempo, usando interfaces multimodais interativas em dispositivos móveis, envolvendo gestos e movimento, com o potencial de criar interacções mais naturais, um maior envolvimento, sensação de presença e imersão. A avaliação baseou-se em protótipos de baixa e alta fidelidade e teve resultados positivos. Os utilizadores consideraram a maioria das funcionalidades úteis, satisfatórias, por vezes divertidas, e fáceis de usar. As diferentes opções e modalidades foram consideradas interessantes e adequadas para diferentes cenários de uso que foram identificados e sugeridos. Alguns receios e desafios foram identificados e poderão ser levados em conta em futuros desenvolvimentos, em direcção a formas interativas de acesso a conteúdo mais flexíveis e eficazes, através de interacções mais naturais com dispositivos móveis, por si só ou como segundos ecrãs relativamente a ecrãs maiores numa TV ou em grandes superfícies em espaços públicos.An increasing amount of digital video is accessed, captured, and uploaded to the Web everyday, from different platforms and devices, that increasingly can georeferenced the information they capture and access, allowing to enrich their contextualization. But video search has been limited to keywords, or a set of parameters, providing limited support for temporal and spatial dimensions. Mobile devices are commonly used and increasingly incorporating a wide range of sensors and actuators with the potential to capture and display 360º video and metadata, with the power to support more powerful and immersive video user experiences. We propose novel ways to search, navigate and visualize video leveraging the potential of mobile sensors and interfaces in temporal and spatial dimensions. This work was carried out in the context of the ImTV research project, and proposes novel ways to search and access georeferenced videos, where these dimensions are of central importance, especially by video trajectories shape and speed, and by time, using a multimodal interactive mobile interface, involving gestures and movement, with the potential for more natural interactions, increased engagement, sense of presence and immersion. The evaluation based on low and high-fidelity prototypes had positive results. Users found most features useful, satisfactory, sometimes fun, and easy to use. Different options and modalities were found interesting and adequate for different use scenarios that could be identified and suggested, and some concerns and challenges were identified to be taken into account in future developments, towards more flexible and effective interactive content access, through more natural interaction with mobile devices on their own or as second screens to a larger screen on TV or public displays

    Multimodal and multidimensional geodata interaction and visualization

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    This PhD proposes the development of a Science Data Visualization System, SdVS, that analyzes and presents different kinds of visualizing and interacting techniques with Geo-data, in order to deal with knowledge about Geo-data using GoogleEarth. After that, we apply the archaeological data as a case study, and, as a result, we develop the Archaeological Visualization System, ArVS, using new visualization paradigms and Human-Computer-Interaction techniques based on SdVS. Furthermore, SdVS provides guidelines for developing any other visualization and interacting applications in the future, and how the users can use SdVS system to enhance the understanding and dissemination of knowledge

    Ubiquitous computing and natural interfaces for environmental information

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    Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do Grau de Mestre em Engenharia do Ambiente, perfil Gestão e Sistemas AmbientaisThe next computing revolution‘s objective is to embed every street, building, room and object with computational power. Ubiquitous computing (ubicomp) will allow every object to receive and transmit information, sense its surroundings and act accordingly, be located from anywhere in the world, connect every person. Everyone will have the possibility to access information, despite their age, computer knowledge, literacy or physical impairment. It will impact the world in a profound way, empowering mankind, improving the environment, but will also create new challenges that our society, economy, health and global environment will have to overcome. Negative impacts have to be identified and dealt with in advance. Despite these concerns, environmental studies have been mostly absent from discussions on the new paradigm. This thesis seeks to examine ubiquitous computing, its technological emergence, raise awareness towards future impacts and explore the design of new interfaces and rich interaction modes. Environmental information is approached as an area which may greatly benefit from ubicomp as a way to gather, treat and disseminate it, simultaneously complying with the Aarhus convention. In an educational context, new media are poised to revolutionize the way we perceive, learn and interact with environmental information. cUbiq is presented as a natural interface to access that information

    From GeoVisualization to visual-analytics: methodologies and techniques for human-information discourse

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    2010 - 2011The objective of our research is to give support to decision makers when facing problems which require rapid solutions in spite of the complexity of scenarios under investigation. In order to achieve this goal our studies have been focused on GeoVisualization and GeoVisual Analytics research field, which play a relevant role in this scope, because they exploit results from several disciplines, such as exploratory data analysis and GIScience, to provide expert users with highly interactive tools by which they can both visually synthesize information from large datasets and perform complex analytical tasks. The research we are carrying out along this line is meant to develop software applications capable both to build an immediate overview of a scenario and to explore elements featuring it. To this aim, we are defining methodologies and techniques which embed key aspects from different disciplines, such as augmented reality and location-based services. Their integration is targeted to realize advanced tools where the geographic component role is primary and is meant to contribute to a human-information discourse... [edited by author]X n.s

    Evaluating indoor positioning systems in a shopping mall : the lessons learned from the IPIN 2018 competition

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    The Indoor Positioning and Indoor Navigation (IPIN) conference holds an annual competition in which indoor localization systems from different research groups worldwide are evaluated empirically. The objective of this competition is to establish a systematic evaluation methodology with rigorous metrics both for real-time (on-site) and post-processing (off-site) situations, in a realistic environment unfamiliar to the prototype developers. For the IPIN 2018 conference, this competition was held on September 22nd, 2018, in Atlantis, a large shopping mall in Nantes (France). Four competition tracks (two on-site and two off-site) were designed. They consisted of several 1 km routes traversing several floors of the mall. Along these paths, 180 points were topographically surveyed with a 10 cm accuracy, to serve as ground truth landmarks, combining theodolite measurements, differential global navigation satellite system (GNSS) and 3D scanner systems. 34 teams effectively competed. The accuracy score corresponds to the third quartile (75th percentile) of an error metric that combines the horizontal positioning error and the floor detection. The best results for the on-site tracks showed an accuracy score of 11.70 m (Track 1) and 5.50 m (Track 2), while the best results for the off-site tracks showed an accuracy score of 0.90 m (Track 3) and 1.30 m (Track 4). These results showed that it is possible to obtain high accuracy indoor positioning solutions in large, realistic environments using wearable light-weight sensors without deploying any beacon. This paper describes the organization work of the tracks, analyzes the methodology used to quantify the results, reviews the lessons learned from the competition and discusses its future

    Geomatics and Forensic: Progress and Challenges

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    Since graphics hold qualitative and quantitative information of complex crime scenes, it becomes a basic key to develop hypothesis in police investigations and also to prove these hypotheses in court. Forensic analysis involves tasks of scene information mining as well as its reconstruction in order to extract elements for explanatory police test or to show forensic evidence in legal proceedings. Currently, the combination of sensors and technologies allows the integration of spatial data and the generation of virtual infographic products (orthoimages, solid images, point clouds, cross‐sections, etc.) which are extremely attractive. These products, which successfully retain accurate 3D metric information, are revolutionizing dimensional reconstruction of objects and crime scenes. Thus, it can be said that the reconstruction and 3D visualization of complex scenes are one of the main challenges for the international scientific community. To overcome this challenge, techniques related with computer vision, computer graphics and geomatics work closely. This chapter reviews a set of geomatic techniques, applied to improve infographic forensic products, and its evolution. The integration of data from different sensors whose final purpose is 3D accurate modelling is also described. As we move into a highly active research area, where there are still many uncertainties to be resolved, the final section addresses these challenges and outlines future perspectives

    Collaborative geographic visualization

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    Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia do Ambiente, perfil Gestão e Sistemas AmbientaisThe present document is a revision of essential references to take into account when developing ubiquitous Geographical Information Systems (GIS) with collaborative visualization purposes. Its chapters focus, respectively, on general principles of GIS, its multimedia components and ubiquitous practices; geo-referenced information visualization and its graphical components of virtual and augmented reality; collaborative environments, its technological requirements, architectural specificities, and models for collective information management; and some final considerations about the future and challenges of collaborative visualization of GIS in ubiquitous environment

    Uses and Challenges of Collecting LiDAR Data from a Growing Autonomous Vehicle Fleet: Implications for Infrastructure Planning and Inspection Practices

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    Autonomous vehicles (AVs) that utilize LiDAR (Light Detection and Ranging) and other sensing technologies are becoming an inevitable part of transportation industry. Concurrently, transportation agencies are increasingly challenged with the management and tracking of large-scale highway asset inventory. LiDAR has become popular among transportation agencies for highway asset management given its advantage over traditional surveying methods. The affordability of LiDAR technology is increasing day by day. Given this, there will be substantial challenges and opportunities for the utilization of big data resulting from the growth of AVs with LiDAR. A proper understanding of the data size generated from this technology will help agencies in making decisions regarding storage, management, and transmission of the data. The original raw data generated from the sensor shrinks a lot after filtering and processing following the Cache county Road Manual and storing into ASPRS recommended (.las) file format. In this pilot study, it is found that while considering the road centerline as the vehicle trajectory larger portion of the data fall into the right of way section compared to the actual vehicle trajectory in Cache County, UT. And there is a positive relation between the data size and vehicle speed in terms of the travel lanes section given the nature of the selected highway environment
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