Use Case Europeana

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Name

Europeana (Metadata aggregation for accessing digitized objects)

Owner

Antoine Isaac

Background and Current Practice

Where this use case takes place in a specific domain, and so requires some prior information to understand, this section is used to describe that domain. As far as possible, please put explanation of the domain in here, to keep the scenario as short as possible. If this scenario is best illustrated by showing how applying technology could replace current existing practice, then this section can be used to describe the current practice. Often, the key to why a use case is important also lies in what problem would occur if it was not achieved, or what problem means it is hard to achieve.

Europeana provides a service to link archives, libraries, museums and audio-visual material from across Europe. It aggregates metadata from various cultural heritage providers. It allows to search in a unified way various object collections using that metadata through a web portal or an API. It aims at easing further re-use and reference to the digitized objects it refers to.

This practice is similar to what is being carried out in a number of aggregator or union catalog projects, such as WorldCat [1], CultureGrid [2]...

Currently the practice is hindered by the wide variety of metadata formats used: it is possible to require providers to submit metadata using one unified model, but usually this results in losing useful information. It is also difficult to harvest (or create), maintain and exploit links that connect objects to contextual information, both within the collections of objects aggregated by the project and between these objects and external resources (e.g., wikipedia). While these links may be present, e.g., through the use of knowledge organization systems that make reference to similar concepts or identical persons. Re-use of objects and their accompanying data is also hampered by the rigidity of the means to access them (Portal and APIs).

Goal

Two short statements stating (1) what is achieved in the scenario without reference to linked data, and (2) how we use linked data technology to achieve this goal.

(1) Three sub-goals can be identified:

  • harvesting object metadata and links to digitized objects
  • contextualizing objects
  • provide access to objects

(2) Linked data can help to:

  • harvest object metadata that connects to resources that are not maintained by providers
  • enhance semantic interoperability between various metadata models, allowing several levels of genericity to co-exist within one same knowledge base
  • enrich existing metadata by providing resources to link them to
  • enhance search processes by allowing to exploit richer and more varied data
  • provide low-level, easy access to metadata to third-parties for them to re-use and access digital objects

Use Case Scenario

The use case scenario itself, described as a story in which actors interact with systems. This section should focus on the user needs in this scenario. Do not mention technical aspects and/or the use of linked data.

The providers contribute object metadata as precise as possible, mapping it to a core vocabulary that ensures minimal interoperability. They can include pointers to other (linked data) resources which can be harvested by Europeana. They can also provide contextual data in the form of knowledge organization systems or authority files.

European enriches metadata, by connecting object descriptions to knowledge organization systems and connecting together knowledge organization systems.

Object description and contextual data are exploited in appropriate search mechanisms (cf. semantic search use case) which enables users to retrieve objects that match better their information need, or explore the object space in a more entertaining/serendipitous way.

Metadata is provided next to the objects to enable appropriate re-use and reference to them in other systems (depending on providers' agreement)

Target audience

  • general public
  • scholars and students
  • providers (museums, libraries, (audio-visual) archives)
  • third-party service providers willing to provide access to digitized culture objects

Application of linked data for the given use case

This section describes how linked data technology could be used to support the use case above. Try to focus on linked data on an abstract level, without mentioning concrete applications and/or vocabularies. Hint: Nothing library domain specific.

Linked data and other semantic web techniques can be used in the following way:

  • harvest better contextualized object metadata, by ingesting links between objects and other contextual linked data resources when data providers have these
  • allow several levels of genericity to co-exist within one same knowledge base, using RDF/OWL axioms (e.g. sub-property or sub-class links)
  • enrich existing metadata, making it easier to represent and maintain links within the different resources of interest to Europeana which are not yet connected by its providers
  • enhance search processes by exploiting the links between objects and their contextual resources, which are described in a richer way (e.g. multilingual labelling of concepts, semantic relations between concepts)
  • provide a direct access to metadata over HTTP to allow third-parties to re-use them

Existing Work (optional)

This section is used to refer to existing technologies or approaches which achieve the use case. Hint: Specific approaches in the library domain.

  • Experimenting with semantic search using RDF for collections and (aligned) KOSs: Europeana semantic search Thought Lab [3], CultureSampo [7]
  • Data aggregators exploring linked data: SOCH [4], CultureGrid [5]

Related Vocabularies (optional)

Here you can list and clarify the use of vocabularies (element sets and value vocabularies) which can be helpful and applied within this context.

Reference models (re-used or adapted in the Europeana Data Model [6]) - dcterms, SKOS, OAI-ORE, CIDOC-CRM, FRBR

Reference value vocabularies - VIAF, Geonames, ULAN, TGN, AAT, DDC, UDC, Iconclass, dbPedia

Any value vocabulary maintained by one provider (that submits objects described using this vocabulary) can be relevant.

Problems and Limitations

This section lists reasons why this scenario is or may be difficult to achieve, including pre-requisites which may not be met, technological obstacles etc. Please explicitly list here the technical challenges made apparent by this use case. This will aid in creating a roadmap to overcome those challenges.

  • Variety of data (metadata schemas + KOS) requires metadata schema mapping and semantic alignment of KOS.
  • Amount of data raises scalability issues.
  • Lack of rich semantics for original data (e.g., no relation to KOSs in object metadata) require semantic enrichment.
  • Moving to a semantic web or linked data environment creates technical hurdles for providers.

Related Use Cases and Unanticipated Uses (optional)

The scenario above describes a particular case of using linked data. However, by allowing this scenario to take place, the likely solution allows for other use cases. This section captures unanticipated uses of the same system apparent in the use case scenario.

  • Publishing 20th Century Press Archive case explores how a provider may publish linked data valuable for ingestion by a provider such as Europeana. Open Library Data case aims at publishing rich data that could be used as a reference set of FRBR and FRAD entities for the library domain.
  • Authority Data Enrichment case can be likened to the semantic alignment necessary to cope with heterogeneity of KOSs and authority files. Europeana may also provide material for this case, by making accessible a large numbers of local KOSs and authority resources.
  • Authority Data Enrichment case can be likened to the semantic alignment necessary to cope with heterogeneity of KOSs and authority files. Europeana may also provide material for this case, by making accessible a large numbers of local KOSs and authority resources.
  • Language Technology case features named entity recognition, a key tool to relate objects that are poorly described to richer resources, or to cross language barriers.
  • Bibliographic Network case enhances search results by using an enriched semantic layer of objects, Subject Search case does it using a single existing KOS.

Library Linked Data Dimensions / Topics

The dimensions and topics are used to organize the use cases. At the same time, they might help you to identify additional aspects currently not covered. If appropriate topics and/or dimensions are missing, please specify them here and annotate them by a “*”.

Dimensions:

  • Users needs > Browse / explore / select
  • Users needs > Retrieve / find
  • Users needs > Access / obtain
  • Users needs > Integrate / contextualize
  • Context > Communication > Online access
  • Systems> library and non-library system connections
  • Information assets > Books, Journal articles, Thesauri and controlled vocabularies, Multimedia materials, Archival materials
  • Information lifecycle: pretty much everything.

Topics: probably too many of them to be relevant

References (optional)

[1] http://www.worldcat.org

[2] http://www.culturegrid.org.uk/

[3] http://www.europeana.eu/portal/thoughtlab_semanticsearching.html

[4] http://www.ksamsok.se/in-english/

[5] http://www.collectionstrust.org.uk/digital/linkeddata

[6] See EDM Definition and EDM Primer at http://group.europeana.eu/web/europeana-project/technicaldocuments/

[7] http://www.archimuse.com/mw2009/papers/hyvonen/hyvonen.html