1,571 research outputs found

    Ontology-Based Quality Evaluation of Value Generalization Hierarchies for Data Anonymization

    Full text link
    In privacy-preserving data publishing, approaches using Value Generalization Hierarchies (VGHs) form an important class of anonymization algorithms. VGHs play a key role in the utility of published datasets as they dictate how the anonymization of the data occurs. For categorical attributes, it is imperative to preserve the semantics of the original data in order to achieve a higher utility. Despite this, semantics have not being formally considered in the specification of VGHs. Moreover, there are no methods that allow the users to assess the quality of their VGH. In this paper, we propose a measurement scheme, based on ontologies, to quantitatively evaluate the quality of VGHs, in terms of semantic consistency and taxonomic organization, with the aim of producing higher-quality anonymizations. We demonstrate, through a case study, how our evaluation scheme can be used to compare the quality of multiple VGHs and can help to identify faulty VGHs.Comment: 18 pages, 7 figures, presented in the Privacy in Statistical Databases Conference 2014 (Ibiza, Spain

    Improved Generalization for Secure Data Publishing

    Get PDF
    In data publishing, privacy and utility are essential for data owners and users respectively, which cannot coexist well. This incompatibility puts the data privacy researchers under an obligation to find newer and reliable privacy preserving tradeoff-techniques. Data providers like many public and private organizations (e.g. hospitals and banks) publish microdata of individuals for various research purposes. Publishing microdata may compromise the privacy of individuals. To prevent the privacy of individuals, data must be published after removing personal identifiers like name and social security numbers. Removal of the personal identifiers appears as not enough to protect the privacy of individuals. K-anonymity model is used to publish microdata by preserving the individual's privacy through generalization. There exist many state-of-the-arts generalization-based techniques, which deal with pre-defined attacks like background knowledge attack, similarity attack, probability attack and so on. However, existing generalization-based techniques compromise the data utility while ensuring privacy. It is an open question to find an efficient technique that is able to set a trade-off between privacy and utility. In this paper, we discussed existing generalization hierarchies and their limitations in detail. We have also proposed three new generalization techniques including conventional generalization hierarchies, divisors based generalization hierarchies and cardinality-based generalization hierarchies. Extensive experiments on the real-world dataset acknowledge that our technique outperforms among the existing techniques in terms of better utility

    Hierarchical testing designs for pattern recognition

    Full text link
    We explore the theoretical foundations of a ``twenty questions'' approach to pattern recognition. The object of the analysis is the computational process itself rather than probability distributions (Bayesian inference) or decision boundaries (statistical learning). Our formulation is motivated by applications to scene interpretation in which there are a great many possible explanations for the data, one (``background'') is statistically dominant, and it is imperative to restrict intensive computation to genuinely ambiguous regions. The focus here is then on pattern filtering: Given a large set Y of possible patterns or explanations, narrow down the true one Y to a small (random) subset \hat Y\subsetY of ``detected'' patterns to be subjected to further, more intense, processing. To this end, we consider a family of hypothesis tests for Y\in A versus the nonspecific alternatives Y\in A^c. Each test has null type I error and the candidate sets A\subsetY are arranged in a hierarchy of nested partitions. These tests are then characterized by scope (|A|), power (or type II error) and algorithmic cost. We consider sequential testing strategies in which decisions are made iteratively, based on past outcomes, about which test to perform next and when to stop testing. The set \hat Y is then taken to be the set of patterns that have not been ruled out by the tests performed. The total cost of a strategy is the sum of the ``testing cost'' and the ``postprocessing cost'' (proportional to |\hat Y|) and the corresponding optimization problem is analyzed.Comment: Published at http://dx.doi.org/10.1214/009053605000000174 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

    An extensible framework for provenance in human terrain visual analytics

    Get PDF
    We describe and demonstrate an extensible framework that supports data exploration and provenance in the context of Human Terrain Analysis (HTA). Working closely with defence analysts we extract requirements and a list of features that characterise data analysed at the end of the HTA chain. From these, we select an appropriate non-classified data source with analogous features, and model it as a set of facets. We develop ProveML, an XML-based extension of the Open Provenance Model, using these facets and augment it with the structures necessary to record the provenance of data, analytical process and interpretations. Through an iterative process, we develop and refine a prototype system for Human Terrain Visual Analytics (HTVA), and demonstrate means of storing, browsing and recalling analytical provenance and process through analytic bookmarks in ProveML. We show how these bookmarks can be combined to form narratives that link back to the live data. Throughout the process, we demonstrate that through structured workshops, rapid prototyping and structured communication with intelligence analysts we are able to establish requirements, and design schema, techniques and tools that meet the requirements of the intelligence community. We use the needs and reactions of defence analysts in defining and steering the methods to validate the framework

    Multiscale visualization approaches for Volunteered Geographic Information and Location-based Social Media

    Get PDF
    Today, “zoomable” maps are a state-of-the-art way to explore the world, available to anyone with Internet access. However, the process of creating this visualization has been rather loosely investigated and documented. Nevertheless, with an increasing amount of available data, interactive maps have become a more integral approach to visualizing and exploring big datasets and user-generated data. OpenStreetMap and online platforms such as Twitter and Flickr offer application programming interfaces (APIs) with geographic information. They are well-known examples of this visualization challenge and are often used as examples. In addition, an increasing number of public administrations collect open data and publish their data sets, which makes the task of visualization even more relevant. This dissertation deals with the visualization of user-generated geodata as a multiscale map. The basics of today’s multiscale maps—their history, technologies, and possibilities—are explored and abstracted. This work introduces two new multiscale-focused visualization approaches for point data from volunteered geographic information (VGI) and location-based social media (LBSM). One contribution of this effort is a visualization methodology for spatially referenced information in the form of point geometries, using nominally scaled data from social media such as Twitter or Flickr. Typical for this data is a high number of social media posts in different categories—a post on social media corresponds to a point in a specific category. Due to the sheer quantity and similar characteristics, the posts appear generic rather than unique. This type of dataset can be explored using the new method of micro diagrams to visualize the dataset on multiple scales and resolutions. The data is aggregated into small grid cells, and the numerical proportion is shown with small diagrams, which can visually merge into heterogenous areas through colors depicting a specific category. The diagram sizes allow the user to estimate the overall number of aggregated points in a grid cell. A different visualization approach is proposed for more unique points, considered points of interest (POI), based on the selection method. The goal is to identify more locally relevant points from the data set, considered more important compared to other points in the neighborhood, which are then compared by numerical attribute. The method, derived from topographic isolation and called discrete isolation, is the distance from one point to the next with a higher attribute value. By using this measure, the most essential points can be easily selected by choosing a minimum distance and producing a homogenous spatial of the selected points within the chosen dataset. The two newly developed approaches are applied to multiscale mapping by constructing example workflows that produce multiscale maps. The publicly available multiscale mapping workflows OpenMapTiles and OpenStreetMap Carto, using OpenStreetMap data, are systematically explored and analyzed. The result is a general workflow for multiscale map production and a short overview of the toolchain software. In particular, the generalization approaches in the example projects are discussed and these are classified into cartographic theories on the basis of literature. The workflow is demonstrated by building a raster tile service for the micro diagrams and a vector tile service for the discrete isolation, able to be used with just a web browser. In conclusion, these new approaches for point data using VGI and LBSM allow better qualitative visualization of geodata. While analyzing vast global datasets is challenging, exploring and analyzing hidden data patterns is fruitful. Creating this degree of visualization and producing maps on multiple scales is a complicated task. The workflows and tools provided in this thesis will make map production on a worldwide scale easier.:1 Introduction 1 1.1 Motivation .................................................................................................. 3 1.2 Visualization of crowdsourced geodata on multiple scales ............ 5 1.2.1 Research objective 1: Visualization of point collections ......... 6 1.2.2 Research objective 2: Visualization of points of interest ......... 7 1.2.3 Research objective 3: Production of multiscale maps ............. 7 1.3 Reader’s guide ......................................................................................... 9 1.3.1 Structure ........................................................................................... 9 1.3.2 Related Publications ....................................................................... 9 1.3.3 Formatting and layout ................................................................. 10 1.3.4 Online examples ........................................................................... 10 2 Foundations of crowdsourced mapping on multiple scales 11 2.1 Types and properties of crowdsourced data .................................. 11 2.2 Currents trends in cartography ......................................................... 11 2.3 Definitions .............................................................................................. 12 2.3.1 VGI .................................................................................................. 12 2.3.2 LBSM .............................................................................................. 13 2.3.3 Space, place, and location......................................................... 13 2.4 Visualization approaches for crowdsourced geodata ................... 14 2.4.1 Review of publications and visualization approaches ........... 14 2.4.2 Conclusions from the review ...................................................... 15 2.4.3 Challenges mapping crowdsourced data ................................ 17 2.5 Technologies for serving multiscale maps ...................................... 17 2.5.1 Research about multiscale maps .............................................. 17 2.5.2 Web Mercator projection ............................................................ 18 2.5.3 Tiles and zoom levels .................................................................. 19 2.5.4 Raster tiles ..................................................................................... 21 2.5.5 Vector tiles .................................................................................... 23 2.5.6 Tiling as a principle ..................................................................... 25 3 Point collection visualization with categorized attributes 26 3.1 Target users and possible tasks ....................................................... 26 3.2 Example data ......................................................................................... 27 3.3 Visualization approaches .................................................................... 28 3.3.1 Common techniques .................................................................... 28 3.3.2 The micro diagram approach .................................................... 30 3.4 The micro diagram and its parameters ............................................ 33 3.4.1 Aggregating points into a regular structure ............................ 33 3.4.2 Visualizing the number of data points ...................................... 35 3.4.3 Grid and micro diagrams ............................................................ 36 3.4.4 Visualizing numerical proportions with diagrams .................. 37 3.4.5 Influence of color and color brightness ................................... 38 3.4.6 Interaction options with micro diagrams .................................. 39 3.5 Application and user-based evaluation ............................................ 39 3.5.1 Micro diagrams in a multiscale environment ........................... 39 3.5.2 The micro diagram user study ................................................... 41 3.5.3 Point collection visualization discussion .................................. 47 4 Selection of POIs for visualization 50 4.1 Approaches for point selection .......................................................... 50 4.2 Methods for point selection ................................................................ 51 4.2.1 Label grid approach .................................................................... 52 4.2.2 Functional importance approach .............................................. 53 4.2.3 Discrete isolation approach ....................................................... 54 4.3 Functional evaluation of selection methods .................................... 56 4.3.1 Runtime comparison .................................................................... 56 4.3.2 Use cases for discrete isolation ................................................ 57 4.4 Discussion of the selection approaches .......................................... 61 4.4.1 A critical view of the use cases ................................................. 61 4.4.2 Comparing the approaches ........................................................ 62 4.4.3 Conclusion ..................................................................................... 64 5 Creating multiscale maps 65 5.1 Examples of multiscale map production .......................................... 65 5.1.1 OpenStreetMap Infrastructure ................................................... 66 5.1.2 OpenStreetMap Carto ................................................................. 67 5.1.3 OpenMapTiles ............................................................................... 73 5.2 Methods of multiscale map production ............................................ 80 5.2.1 OpenStreetMap tools ................................................................... 80 5.2.2 Geoprocessing .............................................................................. 80 5.2.3 Database ........................................................................................ 80 5.2.4 Creating tiles ................................................................................. 82 5.2.5 Caching .......................................................................................... 82 5.2.6 Styling tiles .................................................................................... 82 5.2.7 Viewing tiles ................................................................................... 83 5.2.8 The stackless approach to tile creation ................................... 83 5.3 Example workflows for creating multiscale maps ........................... 84 5.3.1 Raster tiles: OGC services and micro diagrams .................... 84 5.3.2 Vector tiles: Slippy map and vector tiles ................................. 87 5.4 Discussion of approaches and workflows ....................................... 90 5.4.1 Map production as a rendering pipeline .................................. 90 5.4.2 Comparison of OpenStreetMap Carto and OpenMapTiles .. 92 5.4.3 Discussion of the implementations ........................................... 93 5.4.4 Generalization in map production workflows .......................... 95 5.4.5 Conclusions ................................................................................. 101 6 Discussion 103 6.1 Development for web mapping ........................................................ 103 6.1.1 The role of standards in map production .............................. 103 6.1.2 Technological development ..................................................... 103 6.2 New data, new mapping techniques? ............................................. 104 7 Conclusion 106 7.1 Visualization of point collections ..................................................... 106 7.2 Visualization of points of interest ................................................... 107 7.3 Production of multiscale maps ........................................................ 107 7.4 Synthesis of the research questions .............................................. 108 7.5 Contributions ....................................................................................... 109 7.6 Limitations ............................................................................................ 110 7.7 Outlook ................................................................................................. 111 8 References 113 9 Appendix 130 9.1 Zoom levels and Scale ...................................................................... 130 9.3 Full information about selected UGC papers ................................ 131 9.4 Timeline of mapping technologies .................................................. 133 9.5 Timeline of map providers ................................................................ 133 9.6 Code snippets from own map production workflows .................. 134 9.6.1 Vector tiles workflow ................................................................. 134 9.6.2 Raster tiles workflow.................................................................. 137Heute sind zoombare Karten Alltag fĂŒr jeden Internetznutzer. Die Erstellung interaktiv zoombarer Karten ist allerdings wenig erforscht, was einen deutlichen Gegensatz zu ihrer aktuellen Bedeutung und NutzungshĂ€ufigkeit darstellt. Die Forschung in diesem Bereich ist also umso notwendiger. Steigende Datenmengen und grĂ¶ĂŸere Regionen, die von Karten abgedeckt werden sollen, unterstreichen den Forschungsbedarf umso mehr. Beispiele fĂŒr stetig wachsende Datenmengen sind Geodatenquellen wie OpenStreetMap aber auch freie amtliche GeodatensĂ€tze (OpenData), aber auch die zunehmende Zahl georeferenzierter Inhalte auf Internetplatformen wie Twitter oder Flickr zu nennen. Das Thema dieser Arbeit ist die Visualisierung eben dieser nutzergenerierten Geodaten mittels zoombarer Karten. DafĂŒr wird die Entwicklung der zugrundeliegenden Technologien ĂŒber die letzten zwei Jahr-zehnte und die damit verbundene Möglichkeiten vorgestellt. Weitere BeitrĂ€ge sind zwei neue Visualisierungsmethoden, die sich besonders fĂŒr die Darstellung von Punktdaten aus raumbezogenen nutzergenerierten Daten und georeferenzierte Daten aus Sozialen Netzwerken eignen. Ein Beitrag dieser Arbeit ist eine neue Visualisierungsmethode fĂŒr raumbezogene Informationen in Form von Punktgeometrien mit nominal skalierten Daten aus Sozialen Medien, wie beispielsweise Twitter oder Flickr. Typisch fĂŒr diese Daten ist eine hohe Anzahl von BeitrĂ€gen mit unterschiedlichen Kategorien. Wobei die BeitrĂ€ge, bedingt durch ihre schiere Menge und Ă€hnlicher Ei-genschaften, eher generisch als einzigartig sind. Ein Beitrag in den So-zia len Medien entspricht dabei einem Punkt mit einer bestimmten Katego-rie. Ein solcher Datensatz kann mit der neuen Methode der „micro diagrams“ in verschiedenen MaßstĂ€ben und Auflösungen visualisiert und analysiert werden. Dazu werden die Daten in kleine Gitterzellen aggregiert. Die Menge und Verteilung der ĂŒber die Kategorien aggregierten Punkte wird durch kleine Diagramme dargestellt, wobei die Farben die verschiedenen Kategorien visualisieren. Durch die geringere GrĂ¶ĂŸe der einzelnen Diagramme verschmelzen die kleinen Diagramme visuell, je nach der Verteilung der Farben fĂŒr die Kategorien. Bei genauerem Hinsehen ist die SchĂ€tzung der Menge der aggregierten Punkte ĂŒber die GrĂ¶ĂŸe der Diagramme die Menge und die Verteilung ĂŒber die Kategorien möglich. FĂŒr einzigartigere Punkte, die als Points of Interest (POI) angesehen werden, wird ein anderer Visualisierungsansatz vorgeschlagen, der auf einer Auswahlmethode basiert. Ziel ist es dabei lokal relevantere Punkte aus dem Datensatz zu identifizieren, die im Vergleich zu anderen Punkten in der Nachbarschaft des Punktes verglichen nach einem numerischen Attribut wichtiger sind. Die Methode ist von dem geographischen Prinzip der Dominanz von Bergen abgeleitet und wird „discrete isolation“ genannt. Es handelt sich dabei um die Distanz von einem Punkt zum nĂ€chsten mit einem höheren Attributwert. Durch die Verwendung dieses Maßes können lokal bedeutende Punkte leicht ausgewĂ€hlt werden, indem ein minimaler Abstand gewĂ€hlt und so rĂ€umlich gleichmĂ€ĂŸig verteilte Punkte aus dem Datensatz ausgewĂ€hlt werden. Die beiden neu vorgestellten Methoden werden in den Kontext der zoombaren Karten gestellt, indem exemplarische ArbeitsablĂ€ufe erstellt werden, die als Er-gebnis eine zoombare Karte liefern. Dazu werden die frei verfĂŒgbaren Beispiele zur Herstellung von weltweiten zoombaren Karten mit nutzergenerierten Geo-daten von OpenStreetMap, anhand der Kartenprojekte OpenMapTiles und O-penStreetMap Carto analysiert und in Arbeitsschritte gegliedert. Das Ergebnis ist ein wiederverwendbarer Arbeitsablauf zur Herstellung zoombarer Karten, ergĂ€nzt durch eine Auswahl von passender Software fĂŒr die einzelnen Arbeits-schritte. Dabei wird insbesondere auf die GeneralisierungsansĂ€tze in den Beispielprojekten eingegangen und diese anhand von Literatur in die kartographische Theorie eingeordnet. Zur Demonstration des Workflows wird je ein Raster Tiles Dienst fĂŒr die „micro diagrams“ und ein Vektor Tiles Dienst fĂŒr die „discrete isolation“ erstellt. Beide Dienste lassen sich mit einem aktuellen Webbrowser nutzen. Zusammenfassend ermöglichen diese neuen VisualisierungsansĂ€tze fĂŒr Punkt-daten aus VGI und LBSM eine bessere qualitative Visualisierung der neuen Geodaten. Die Analyse riesiger globaler DatensĂ€tze ist immer noch eine Herausforderung, aber die Erforschung und Analyse verborgener Muster in den Daten ist lohnend. Die Erstellung solcher Visualisierungen und die Produktion von Karten in verschiedenen MaßstĂ€ben ist eine komplexe Aufgabe. Die in dieser Arbeit vorgestellten ArbeitsablĂ€ufe und Werkzeuge erleichtern die Erstellung von Karten in globalem Maßstab.:1 Introduction 1 1.1 Motivation .................................................................................................. 3 1.2 Visualization of crowdsourced geodata on multiple scales ............ 5 1.2.1 Research objective 1: Visualization of point collections ......... 6 1.2.2 Research objective 2: Visualization of points of interest ......... 7 1.2.3 Research objective 3: Production of multiscale maps ............. 7 1.3 Reader’s guide ......................................................................................... 9 1.3.1 Structure ........................................................................................... 9 1.3.2 Related Publications ....................................................................... 9 1.3.3 Formatting and layout ................................................................. 10 1.3.4 Online examples ........................................................................... 10 2 Foundations of crowdsourced mapping on multiple scales 11 2.1 Types and properties of crowdsourced data .................................. 11 2.2 Currents trends in cartography ......................................................... 11 2.3 Definitions .............................................................................................. 12 2.3.1 VGI .................................................................................................. 12 2.3.2 LBSM .............................................................................................. 13 2.3.3 Space, place, and location......................................................... 13 2.4 Visualization approaches for crowdsourced geodata ................... 14 2.4.1 Review of publications and visualization approaches ........... 14 2.4.2 Conclusions from the review ...................................................... 15 2.4.3 Challenges mapping crowdsourced data ................................ 17 2.5 Technologies for serving multiscale maps ...................................... 17 2.5.1 Research about multiscale maps .............................................. 17 2.5.2 Web Mercator projection ............................................................ 18 2.5.3 Tiles and zoom levels .................................................................. 19 2.5.4 Raster tiles ..................................................................................... 21 2.5.5 Vector tiles .................................................................................... 23 2.5.6 Tiling as a principle ..................................................................... 25 3 Point collection visualization with categorized attributes 26 3.1 Target users and possible tasks ....................................................... 26 3.2 Example data ......................................................................................... 27 3.3 Visualization approaches .................................................................... 28 3.3.1 Common techniques .................................................................... 28 3.3.2 The micro diagram approach .................................................... 30 3.4 The micro diagram and its parameters ............................................ 33 3.4.1 Aggregating points into a regular structure ............................ 33 3.4.2 Visualizing the number of data points ...................................... 35 3.4.3 Grid and micro diagrams ............................................................ 36 3.4.4 Visualizing numerical proportions with diagrams .................. 37 3.4.5 Influence of color and color brightness ................................... 38 3.4.6 Interaction options with micro diagrams .................................. 39 3.5 Application and user-based evaluation ............................................ 39 3.5.1 Micro diagrams in a multiscale environment ........................... 39 3.5.2 The micro diagram user study ................................................... 41 3.5.3 Point collection vis

    Hierarchical graphs for rule-based modeling of biochemical systems

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>In rule-based modeling, graphs are used to represent molecules: a colored vertex represents a component of a molecule, a vertex attribute represents the internal state of a component, and an edge represents a bond between components. Components of a molecule share the same color. Furthermore, graph-rewriting rules are used to represent molecular interactions. A rule that specifies addition (removal) of an edge represents a class of association (dissociation) reactions, and a rule that specifies a change of a vertex attribute represents a class of reactions that affect the internal state of a molecular component. A set of rules comprises an executable model that can be used to determine, through various means, the system-level dynamics of molecular interactions in a biochemical system.</p> <p>Results</p> <p>For purposes of model annotation, we propose the use of hierarchical graphs to represent structural relationships among components and subcomponents of molecules. We illustrate how hierarchical graphs can be used to naturally document the structural organization of the functional components and subcomponents of two proteins: the protein tyrosine kinase Lck and the T cell receptor (TCR) complex. We also show that computational methods developed for regular graphs can be applied to hierarchical graphs. In particular, we describe a generalization of Nauty, a graph isomorphism and canonical labeling algorithm. The generalized version of the Nauty procedure, which we call HNauty, can be used to assign canonical labels to hierarchical graphs or more generally to graphs with multiple edge types. The difference between the Nauty and HNauty procedures is minor, but for completeness, we provide an explanation of the entire HNauty algorithm.</p> <p>Conclusions</p> <p>Hierarchical graphs provide more intuitive formal representations of proteins and other structured molecules with multiple functional components than do the regular graphs of current languages for specifying rule-based models, such as the BioNetGen language (BNGL). Thus, the proposed use of hierarchical graphs should promote clarity and better understanding of rule-based models.</p

    World Modeling for Intelligent Autonomous Systems

    Get PDF
    The functioning of intelligent autonomous systems requires constant situation awareness and cognition analysis. Thus, it needs a memory structure that contains a description of the surrounding environment (world model) and serves as a central information hub. This book presents a row of theoretical and experimental results in the field of world modeling. This includes areas of dynamic and prior knowledge modeling, information fusion, management and qualitative/quantitative information analysis

    A Survey of Privacy Preserving Data Publishing using Generalization and Suppression

    Full text link

    Developing a model and a language to identify and specify the integrity constraints in spatial datacubes

    Get PDF
    La qualité des données dans les cubes de données spatiales est importante étant donné que ces données sont utilisées comme base pour la prise de décision dans les grandes organisations. En effet, une mauvaise qualité de données dans ces cubes pourrait nous conduire à une mauvaise prise de décision. Les contraintes d'intégrité jouent un rÎle clé pour améliorer la cohérence logique de toute base de données, l'un des principaux éléments de la qualité des données. Différents modÚles de cubes de données spatiales ont été proposés ces derniÚres années mais aucun n'inclut explicitement les contraintes d'intégrité. En conséquence, les contraintes d'intégrité de cubes de données spatiales sont traitées de façon non-systématique, pragmatique, ce qui rend inefficace le processus de vérification de la cohérence des données dans les cubes de données spatiales. Cette thÚse fournit un cadre théorique pour identifier les contraintes d'intégrité dans les cubes de données spatiales ainsi qu'un langage formel pour les spécifier. Pour ce faire, nous avons d'abord proposé un modÚle formel pour les cubes de données spatiales qui en décrit les différentes composantes. En nous basant sur ce modÚle, nous avons ensuite identifié et catégorisé les différents types de contraintes d'intégrité dans les cubes de données spatiales. En outre, puisque les cubes de données spatiales contiennent typiquement à la fois des données spatiales et temporelles, nous avons proposé une classification des contraintes d'intégrité des bases de données traitant de l'espace et du temps. Ensuite, nous avons présenté un langage formel pour spécifier les contraintes d'intégrité des cubes de données spatiales. Ce langage est basé sur un langage naturel contrÎlé et hybride avec des pictogrammes. Plusieurs exemples de contraintes d'intégrité des cubes de données spatiales sont définis en utilisant ce langage. Les designers de cubes de données spatiales (analystes) peuvent utiliser le cadre proposé pour identifier les contraintes d'intégrité et les spécifier au stade de la conception des cubes de données spatiales. D'autre part, le langage formel proposé pour spécifier des contraintes d'intégrité est proche de la façon dont les utilisateurs finaux expriment leurs contraintes d'intégrité. Par conséquent, en utilisant ce langage, les utilisateurs finaux peuvent vérifier et valider les contraintes d'intégrité définies par l'analyste au stade de la conception

    World Modeling for Intelligent Autonomous Systems

    Get PDF
    The functioning of intelligent autonomous systems requires constant situation awareness and cognition analysis. Thus, it needs a memory structure that contains a description of the surrounding environment (world model) and serves as a central information hub. This book presents a row of theoretical and experimental results in the field of world modeling. This includes areas of dynamic and prior knowledge modeling, information fusion, management and qualitative/quantitative information analysis
    • 

    corecore