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Slovakia’s successful implementation of SEMIC Core Vocabularies

During the webinar on the review of Core Vocabularies which took place in October 2023, Miroslav Liska, a member of the Slovakian Ministry of Investments, Regional Development and Informatisation, shared an inspiring success story. Their story showcases the power of knowledge graphs using SEMIC Core Vocabularies.


The Knowledge Graph

The Slovakian Ministry of Investments, Regional Development and Informatisation developed a centralised knowledge graph that incorporates a diverse range of ontologies, including both national and international standards. These ontologies are often derived from standard models like RDF and RDFS. The subsections of the knowledge graph are interconnected which improves the navigation of this intricate network. This knowledge graph provides all Slovakian governmental institutions with easy access to these common assets described in their own language. It ensures a consistent translation of these assets across Slovakia, guaranteeing that there is no language barrier keeping public authorities from adopting semantic interoperability.  

The knowledge graph is structured into three main sections. The first of which is the terminological box (TBOX), it contains ontologies and their shapes, here we can find CCCEV from the SEMIC Core Vocabularies. The categories box (CBOX) is the second main section, it is a dedicated category segment housing code lists, taxonomies and thesauri. It offers corresponding URIs for taxonomies, covering aspects like continents, countries and frequencies. These first two sections, the TBOX and CBOX, are conceptually divided into national and international assets. The national assets provide metadata that describes the semantics of Slovakian reference data. These ontologies, shapes, code lists, and taxonomies were derived from Slovakian base registries. The international assets, on the other hand, consist of ontologies and taxonomies recommended by the EU, such as the SEMIC Core Vocabularies, EU Authority Tables, and W3C ontologies. These are used to describe all other data that is not stored in base registries. To support international interoperability the TBOX also contains mappings between the national and international assets. The last section of the knowledge graph is the assertion box (ABOX) which is focused on instance data, primarily tailored for developers. This section provides guidance on incorporating linked data into their information systems, and contains examples of interoperable linked government data. 

The main advantage of this knowledge graph lies in its seamless connectivity as it enables users to easily request data in JSON-LD or RDF with the simple click of a button. These features allow the knowledge graph to be a one-stop-shop for interoperability in Slovakia, being relevant to data modellers, developers and publishers. 



In addition to the knowledge graph, the Slovakian government has developed CCCEV-AP-SK, an application profile specifically designed for evidence regulations in Slovakia. This profile follows a straightforward structure similar to CCCEV and serves as a blueprint for developers on how to integrate such evidence types into their information systems. The methodologies portal of the Slovakian government hosts a wealth of regulations related to the implementation of such evidence types. Examples of evidence types that are modelled according to the application profile can be found in the ABOX, and include but are not limited to personal evidence, evidence related to education and evidence related to healthcare.

The Slovakian Ministry of Investments, Regional Development and Informatisation, as a national interoperability coordinator, was able to successfully implement CCCEV independently. They re-used and leveraged CCCEV using the knowledge base and the available documentation provided by SEMIC.

CCCEV-AP-SK was already successfully implemented in two projects. The first is for the Education Registry where a set of APIs can return evidence types in RDF/XML format. A second is a Central Integration Platform which is an intermediate platform that reimplements sources APIs and supports JSON/LD formats of evidence types.

The Slovakian government opted to use CCCEV because it is a common EU standard that is compatible with the Once-Only Technical System (OOTS). In addition, it is a future-proofed standard for any European project because it is aligned with international standards and is adaptable to evolving requirements through its community involvement. In the context of the Slovakian knowledge graph, CCCEV was adapted to an application profile. This highlights the potential of SEMIC’s Core Vocabularies as extensible cornerstones for addressing domain-specific needs. By extending CCCEV the Slovakian government is balancing European interoperability with the need for national specific customisations. 


Future Outlook

The vision of the Slovakian Ministry of Investments, Regional Development and Informatisation extends to the implementation of several regulations, covering a wide array of evidence types, including, for example, ID cards, birth certificates and driving licences.

This Ministry actively engages with stakeholders (including developers) through collaborative working group meetings. They meticulously scrutinise existing data, identify gaps and explore the relationship between data models and evidence. All of this is done while adhering to the "once only" principle, ensuring maximum information alignment and availability.

The Slovakian success story serves as a testament to the effective power of knowledge graphs and collaborative efforts in driving data standardisation. In this effort, SEMIC specifications play a crucial role. Thanks to their reusability, extensibility and adaptability, they foster seamless exchange of public data and enable Member State’s interoperability at an international level. This paves the way for a more interconnected and data-rich future, benefitting both the government and its citizens.

More information can be found on GitHub and for collaborative work an instance of VocBench3 is used.