W3C PROV to describe provenance at the dataset, feature and attribute levels in a distributed environment

Provenance, a metadata component referring to the origin and the processes undertaken to obtain a specific geographic digital feature or product, is crucial to evaluate the quality of spatial information and help in reproducing and replicating geospatial processes. However, the heterogeneity and complexity of the geospatial processes, which can potentially modify part or the complete content of datasets, make evident the necessity for describing geospatial provenance at dataset, feature and attribute levels. This paper presents the application of W3C PROV, which is a generic specification to express provenance records, for representing geospatial data provenance at these different levels. In particular, W3C PROV is applied to feature models, where geospatial phenomena are represented as individual features described with spatial (point, lines, polygons, etc.) and non-spatial (names, measures, etc.) attributes. This paper first analyses the potential for representing geospatial provenance in a distributed environment at the three levels of granularity using ISO 19115 and W3C PROV models. Next, an approach for applying the generic W3C PROV provenance model to the geospatial environment is presented. As a proof of concept, we provide an application of W3C PROV to describe geospatial provenance at the feature and attribute levels. The use case presented consists of a conflation of the U.S. Geological Survey dataset with the National Geospatial-Intelligence Agency dataset. Finally, an example of how to capture the provenance resulting from workflows and chain executions with PROV is also presented. The application uses a web processing service, which enables geospatial processing in a distributed system and allows to capture the provenance information based on the W3C PROV ontology at the feature and attribute levels

iPiccer: Automatically retrieving and inferring tagged location information from web repositories

We present iPiccer, a system that allows mobile camera phones users to interact with meta-tagged image material available from web repositories, such as flickr in two novel ways. Users of the system are able to infer photo tags from their location and orientation, but are also able to infer their location and orientation from their spatial photo tags. An implementation of iPiccerTaker is outlined, and the potential of this new form of interaction with web repository data is discussed. 1

Simulating extreme multi-hazard events with decentralized Web-processing services: Towards a better understanding of cascading impact

The RIESGOS Project (Multi-Risk Analysis And Information System Components for the Andes Region) funded by the German Ministry of Science and education (BMBF) has, as one of its main goals, the design and development of distributed software components for multi-hazard and risk analysis in particular by simulating hypothetical future high-impact events and their consequences. Implemented as an open library of interacting Web-services, these components will cover a full range of multi-hazard and risk related data acquisition and simulation services. These services include, for example: query of a seismic catalog, simulation of a shake map, simulation of a tsunami inundation scenario and assessment of expected damage and loss under consideration of cascading effects to critical infrastructure. Individual Web-services can be flexibly combined to produce multi-hazard scenarios with the ultimate goal to assist local authorities and decision makers to explore factors influencing the risk in their specific multi-hazard environments, thus improving disaster risk reduction and disaster management activities. To facilitate the development of a project which encompasses diverse hazard and risk components of various nature, our research is organized along a set of pre-described ‘event stories’ representing realistic, complex multi-hazard events with cascading effects in selected pilot regions of Chile, Peru and Ecuador. For each story, a storyboard is developed, which provides a narrative description of a hypothetical crisis evolution, defines the specific hazards involved, the related exposed assets and the expected consequences. In particular, these event stories target the following topics: - earthquake and tsunami (Chile and Peru); - heavy rain and river flooding (Peru); - volcano instability, lahar event and subsequent flooding via temporary river blockage (Ecuador). Each story can then be analysed in a more quantitative way by estimating different scenarios through numerical analysis and simulation of the different risk components. Remarkably, the consideration of vulnerability in a multi-hazard risk assessment framework is significantly more challenging with respect to the single hazard case, especially when interaction may occur at the vulnerability level due to physical damage accumulation. Furthermore, the project also aims at considering cascading effects to critical infrastructure such as power grids, roads and bridges. In order to ease up the visual exploration of such a complex multi-risk framework, a Web-based demonstrator platform integrating decentralized OGC Web Processing Service instances into multi-hazard and risk scenarios is being developed. To better meet the requirements of end-users, a thorough analysis of users’ needs and continued user participation during the whole development process is assured