Linked Data

Linked Data is an idea which assumes that all objects of human knowledge can be described using simple clauses – an enormously ambitious task, but according to the founders doable. Such simple clauses consist of only three words, subject, predicate and object. Resource Description Framework (RDF) is the standard that defines how to form such three-part sentences. The most important principles of Linked Data are the use of links called unique identifiers (URI) instead of text and usage of simple affirmative sentence syntax: subject – predicate – object. All the remaining rules of RDF are simple only an extension and/ or their detailed interpretation of these three basic principles. The RDF model is only the core of the Linked Data syntax. RDF is quite versatile, it allows for example the use of well-known and popular metadata standard such as Dublin Core or Friend-of-a-Friend (FOAF). It already has built-in extension, RDF Schema (RDFS), the definition of classes for building ontologies. There are complete ontology languages such as OWL or SKOS, database query language (SPARQL) and a rich set of other tools.

We use linked data model along with database query language SPARQL to store, process and present geographic data. Example is the Polish - Norwegian collaboration project InCoNaDa (Enhancing the user uptake of Land Cover / Land Use information derived from the integration of Copernicus services and national databases). The main goal of the InCoNaDa project is to improve the user uptake of land cover and land use information derived from the integration of Copernicus Land Monitoring Services (CLMS) and national databases.
You can find more information about the project on the website www.inconada.eu.

Linked data turned out to be very helpful during other scientific project called EO4GEO, in which innovative and interactive database of resource describing ontology for the EO/GI fields has been created using this model. More information about this database available on the website: www.eo4geo.eu/bok/