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Auflistung nach Autor:in "Baumann, Peter"

1 - 4 von 4
  • Konferenzbeitrag
    Improving Efficiency of Grid Representation in GML
    (Proceedings of the 27th Conference on Environmental Informatics - Informatics for Environmental Protection, Sustainable Development and Risk Management, 2013) Campalani, Piero; Beccati, Alan; Baumann, Peter
    Earth observation and remote sensing today are a primary resource for a miscellanea of geoservices providing massive timeseries of raster-based datasets. This leads to more complex grid structures than before for example, in a 3-D x/y/t timeseries data cube, regular lat/long axes of some orthoimagery may be combined with irregular time axis. The OGC unified coverage model allows to describe such generalized grid structures through its concept of a Referenceable Grid Coverage. This standard, utilizing GML, is extended by GML 3.3 with new types of geometries that can handle irregular and warped gridded topologies. A shortcoming is, however, that they are efficient only in the special cases described initially. Hybrid situations like the one above can become inconveniently verbose. In this paper, we document first considerations to improve flexibility and modularity of the GML grid models as part of our work to fully unleash all grid types for OGC type Web services. Indeed, in case of hybrid rectilinear and curvilinear grid models there is room for optimization in the existing GML types, presented by means of formal structure definitions and practically motivated examples.
  • Zeitschriftenartikel
    Konzeptuelle Modellierung von Geodiensten
    (Informatik-Spektrum: Vol. 31, No. 5, 2008) Baumann, Peter
    Navigationssysteme, ortsbezogene Suchdienste wie Google Maps, interaktive Augmented-Reality-Spiele, Handy-basierte FindMe-Dienste – diese wenige Beispiele zeigen bereits, wie direkt oder indirekt raumbezogene Dienste unser Alltagsleben immer mehr durchdringen. Wir beobachten, wie sich die Nutzung von Geodaten schrittweise vom persönlichen Desktop-Geoinformationssystem (GIS) über hausinternen Zugriff auf die Geodatenbank bis zum Webzugriff durch Clients und Servern unterschiedlicher Provenienz ausweitet (,,Web-GIS“). Klassische Aufgaben wie Kartenproduktion und Beauskunftung treten dabei gegenüber komplexen, situationsbezogenen Verknüpfungen von Geo- mit anderen Daten eher in den Hintergrund. Damit geht offensichtlich ein Paradigmenwechsel von der einfachen, passiven Geodatenbereitstellung via WWW zu funktional komplexeren Geodiensten einher.Sollen solche Mehrwertdienste offen und flexibel orchestrierbar sein, so müssen Geodaten systemübergreifend ad hoc abgefragt werden können. Unabdingbar sind dafür offene Standards, nicht nur auf der Ebene von Datenaustauschformaten, sondern auch bei den Zugriffsdiensten; diese Geoservice-Standardisierung leistet das Open GeoSpatial Consortium (OGC).Im vorliegenden Beitrag geben wir einen Überblick über die Modellierung von Web-basierten Geodiensten auf Basis ausgewählter OGC-Standards. Modellierung bedeutet in diesem Kontext die Gestaltung von Funktionalität und Schnittstellen eines potenziell komplexen Dienstes auf Basis offener Standards und ihrer Basisdienste und -operationen. Diskutiert werden Standards für den Meta-, Vektor- und Rasterdatenzugriff sowie ein anwendungsorientierter Standard für Sensordaten.
  • Konferenzbeitrag
    Status and Prospects in Geo Raster Service Standardization
    (Environmental Informatics and Systems Research, 2007) Baumann, Peter
    Increasingly raster data are becoming integral component of geo services, since today’s hardware and software technology is powerful enough to allow online access even to objects of Terabyte to Petabyte size. The logical next step from standalone geo Web services are interoperable, community-sharable archive networks, and this raises the question of standardised access interfaces. The Open GeoSpatial Consortium (OGC) develops and promotes geo raster services as part of their geo service standards. Recently version 1.1 of the Web Coverage Service (WCS) has been released, and the Web Coverage Processing Service (WCPS) as a dynamic value-adding raster processing service is under preparation. Both WCS and WCPS are presented in this contribution. The author ist active member of the OGC WCS Revision Working Group, Chair of the WCPS Working Group, and Co-Chair of the Coverages Working Group.
  • Zeitschriftenartikel
    Towards Large-Scale Meteorological Data Services: A Case Study
    (Datenbank-Spektrum: Vol. 12, No. 3, 2012) Misev, Dimitar; Baumann, Peter; Seib, Jürgen
    Meteorological data contribute significantly to “Big Data”, handling multi-dimensional raster data cubes up to 5-D and with single cubes up to multi-Petabyte sizes. Due to the lack of support for raster data, traditionally file-based implementations have been used for serving such data to the community, rather than databases. Array databases overcome this by providing storage and query support.In this paper, we present a case study conducted by Deutscher Wetterdienst (DWD) where extraction and processing of gridded meteorological data sets has been investigated hands-on. Following a brief introduction of the rasdaman DBMS used, we present the database schema used and a series of array queries, selected according to their practical importance in weather forecast services. We discuss several issues that have come up, such as null values and time modeling, and how they have been addressed. To the best of our knowledge, this is the first non-academic deployment of an array database for up to 5-D data sets.