Abstract. In the semantic web environment it is important to be able to specify access control requirements about subjects accessing the information and about resources to be accessed in terms of the rich ontologybased metadata describing them. In this paper, we outline how current standard policy languages such as XACML can be extended to address this issue. Then, we describe a reference architecture for enforcing our semantics-aware policies.

EDI is a general purpose, template-driven metadata editor for creating XML-based descriptions. Originally aimed at defining rich and standard metadata for geospatial resources, It can be easily customised in order to comply with a broad range of schemata and domains. EDI creates HTML5 [9] metadata forms with advanced assisted editing capabilities and compiles them into XML files. The examples included in the distribution implement profiles of the ISO 19139 standard for geographic information [14], such as core INSPIRE metadata [10], as well as the OGC [8] standard for sensor description, SensorML [11]. Templates (the blueprints for a specific metadata format) drive form behaviour by element data types and provide advanced features like codelists 1 underlying combo boxes or autocompletion functionalities. Virtually, the editing of any metadata format can be supported by creating a specific template.

The implementation of the INSPIRE Directive in Europe and similar efforts around the globe to develop spatial data infrastructures and global systems of systems have been largely focusing on the adoption of agreed technologies, standards, and specifications to address the interoperability challenge. However, addressing the key scientific challenges of humanity in the 21st century requires a more comprehensive integrative research effort, which in turn may pose more complex requirements on the systems to be integrated, and increase the number of arrangements required to support them. This paper analyses the main challenges related to integrative interoperability, such as mutual understanding of requirements and methods, theoretical underpinning, and tacit knowledge. To illustrate our contribution to the integrative research, the paper proposes the flexible approach to interoperability, based on mediation and brokering, that has been implemented by the EuroGEOSS research project. It also demonstrates that this approach allows scientific and non-scientific stakeholders to overcome the increased complexity of the integration effort mentioned above and charts the trajectory for the evolution of current spatial data infrastructures.Index Terms-Geographic information systems, geoscience and remote sensing, integrative research, research initiatives.

No abstract

Abstract:Metadata management is an essential enabling factor for geospatial assets because discovery, retrieval, and actual usage of the latter are tightly bound to the quality of these descriptions. Unfortunately, the multi-faceted landscape of metadata formats, requirements, and conventions makes it difficult to identify editing tools that can be easily tailored to the specificities of a given project, workgroup, and Community of Practice. Our solution is a template-driven metadata editing tool that can be customised to any XML-based schema. Its output is constituted by standards-compliant metadata records that also have a semantics-aware counterpart eliciting novel exploitation techniques. Moreover, external data sources can easily be plugged in to provide autocompletion functionalities on the basis of the data structures made available on the Web of Data. Beside presenting the essentials on customisation of the editor by means of two use cases, we extend the methodology to the whole life cycle of geospatial metadata. We demonstrate the novel capabilities enabled by RDF-based metadata representation with respect to traditional metadata management in the geospatial domain.