Erkki Heino

WarSampo Knowledge Graph includes harmonized data of different kinds concerning the Second World War in Finland, separated in different subgraphs representing events, actors, places, photographs, and other aspects and documentation of the war. The data covers the Winter War 1939-1940 against the Soviet attack, the Continuation War 1941-1944 where the occupied areas of the Winter War were temporarily regained, and the Lapland War 1944-1945, where the Finns pushed the German troops away from Lapland.

One of the great promises of Linked Data and the Semantic Web standards is to provide a shared data infrastructure into which more and more data can be imported and aligned, forming a sustainable, ever growing knowledge graph or linked data cloud, Web of Data. This paper studies and evaluates this idea in the context of the WarSampo Linked Data cloud, providing an infrastructure for data related to the Second World War in Finland. As a case study, a new database of prisoners of war with related contents is transformed into linked data and integrated into WarSampo. Lessons learned are discussed in relation to using traditional data publishing approaches.

War history of the Second World War (WW2), humankind’s largest disaster, is of great interest to both laymen and researchers. Most of us have ancestors and relatives who participated in the war, and in the worst case got killed. Researchers are eager to find out what actually happened then, and even more importantly why, so that future wars could perhaps be prevented. The darkest data of war history are casualty records—from such data we could perhaps learn most about the war. This paper presents a model and system for representing death records as linked data, so that 1) citizens could find out more easily what happened to their relatives during WW2 and 2) digital humanities (DH) researchers could (re)use the data easily for research.

This paper describes the ontology model and published datasets of a digitized biographical person register. The applied ontology model is designed to represent people via their enduring roles and perduring lifetime events. The model is designed to support 1) prosopographical Digital Humanities research, 2) linking to resources in semantic Cultural Heritage portals, and 3) semantic data validation and enrichment by using SPARQL queries. The linked data approach enables to enrich a person s biography by interlinking it with space and time related biographical events, persons relating by social contacts or family relations, historical events, and personal achievements.

This paper presents a model for representing historical military personnel and army units, based on large datasets about World War II in Finland. The model is in use in WarSampo data service and semantic portal, which has had tens of thousands of distinct visitors. A key challenge is how to represent ontological changes, since the ranks and units of military personnel, as well as the names and structures of army units change rapidly in wars. This leads to serious problems in both search as well as data linking due to ambiguity and homonymy of names. In our solution, actors are represented in terms of the events they participated in, which facilitates disambiguation of personnel and units in different spatio-temporal contexts. The linked data in the WarSampo Linked Open Data cloud and service has ca. 9 million triples, including actor datasets of ca. 100 000 soldiers and ca. 16 100 army units. To test the model in practice, an application for semantic search and recommending based on data linking was created, where the spatio-temporal life stories of individual soldiers can be reassembled dynamically by linking data from different datasets. An evaluation is presented showing promising results in terms of linking precision.

This paper presents an application for studying the death records of WW2 casualties from a prosopograhical perspective, provided by the various local military cemeteries where the dead were buried. The idea is to provide the end user with a global visual map view on the places in which the casualties were buried as well as with a local historical perspective on what happened to the casualties that lay within a particular cemetery of a village or town. Plenty of data exists about the Second World War (WW2), but the data is typically archived in unconnected, isolated silos in different organizations. This makes it difficult to track down, visualize, and study information that is contained within multiple distinct datasets. In our work, this problem is solved using aggregated Linked Open Data provided by the WarSampo Data Service and SPARQL endpoint.

The article overviews the system WarSampo – Finnish World War 2 on the Semantic Web, the winner of the LODLAM Challenge 2017 Open Data Prize on June 29 in Venice, Italy.

This paper discusses the challenges of applying named entity linking in a rich, complex domain – specifically, the linking of 1) military units, 2) places and 3) people in the context of rich Second World War data. Multiple sub-scenarios are discussed in detail through concrete evaluations, analyzing the problems faced, and the solutions developed. A key contribution of this work is to highlight the heterogeneity of problems and approaches needed even inside a single domain, depending on both the source data as well as the target authority.

Linkitetty data mahdollistaa erillisten aineistojen yhdistämisen, mistä syntyvä kokonaisuus mahdollistaa aineistojen tietojen paremman ymmärtämisen. Aineistojen välisten linkkien avulla voidaan päätellä uutta tietoa helpommin kuin tarkastelemalla aineistoja erikseen. Tutkielmassa käsitellään sotahistoriallisten aineistojen mallintamista ja julkaisua linkitettynä avoimena datana sekä aineistojen automaattista rikastamista muiden aineistojen avulla. Työn tavoitteena oli selvittää miten tällaisia aineistoja kannattaa mallintaa linkitettynä datana, miten niitä kannattaa yhdistää muihin aineistoihin, mitä lisäarvoa tästä saadaan ja miten aineistot kannattaa visualisoida. Aineistoina käytettiin tietokirjoista digitoituja tapahtumia sekä Sotamuseon SA-kuvapalvelun valokuvien metatietoja. Aineistot mallinnettiin käyttäen CIDOC CRM -standardia ja niitä rikastettiin linkittämällä niiden sisältämiä resursseja automaattisesti henkilö-, joukko-osasto- ja paikkaontologioiden avulla. CIDOC CRM:n määrittämä tapahtumakeskeinen mallinnustapa mahdollistaa aineistojen yhteentoimivuuden paitsi toistensa myös muiden historiallisten aineistojen kanssa. Automaattiseen rikastamiseen liittyi monia haasteita, sillä viittaukset toisiin aineistoihin oli poimittava suurelta osin tekstimuotoisista kuvauksista, jolloin ongelmaksi nousee nimettyjen entiteettien kuten henkilöiden ja paikkojen tunnistaminen ja yksilöinti tekstistä. Työssä käsitellään kyseisiä haasteita, esitellään käytetyt ratkaisut ja arvioidaan näiden toimivuutta. Aineistoja visualisoimaan toteutettiin myös JavaScript-sovellukset. Aineistot ja sovellukset on julkaistu osana Sotasampo-portaalia, joka muodostaa yhteenlinkitetyn kokonaisuuden erilaisista aineistoista liittyen toiseen maailmansotaan Suomessa. Portaali palvelee paitsi Suomen historiasta ja sodissa taistelleiden omaistensa liikkeistä kiinnostuneita kansalaisia, myös historian tutkijoita tarjoamalla aineistot vapaasti kyseltävässä rakenteisessa muodossa.

This paper presents an automatic annotation tool AATOS for providing documents with semantic annotations. The tool links entities found from the texts to ontologies defined by the user. The application is highly configurable and can be used with different natural language Finnish texts. The application was developed as a part of WarSampo and Semantic Finlex projects and tested using Kansa Taisteli magazine articles and consolidated Finnish legislation of Semantic Finlex. The quality of the automatic annotation was evaluated by measuring precision and recall against existing manual annotations. The results showed that the quality of the input text, as well as the selection and configuration of the ontologies impacted the results.

This paper presents the idea to enrich printed biographical person registers with linked data related to events that took place after the register was published. By transforming printed historical documents into structured data, semantic search to written texts can be provided for the reader. Even more importantly, life stories of historical persons can be extended based on data linking by extracting semantic structures from printed texts, and by combining this data with external datasets and data services. Such linking provides an enriched context for prosopographical research on people in the register, as well as an enhanced reading experience for anyone interested in reading the biographies. As a concrete case study, a register 1867–1992 of over 10 000 alumni of the prominent Finnish high school “Norssi” was transformed into RDF, was enriched by data linking, was published as a linked data service, and is provided to end users via a faceted search engine and browser for studying lives of historical persons and for prosopographical research.

Data about wars is typically heterogeneous, distributed in the data silos of the fighting parties, multilingual, and often controversial depending on the political point of view. It is therefore hard for the historians to get a global picture of what has actually happened, to whom, where, when, and how. We argue that Semantic Web and Linked Data technologies are a very promising approach for modeling, harmonizing, and aggregating data about war history. Our goal is to make it possible, for both historians and laymen, to study history in a contextualized way where linked datasets enrich each other. The paper presents the in-use WarSampo 1 system, where massive collections of heterogeneous data about the (Finnish) history of the Second World War are harmonized using an event-based approach, and provided as a Linked Open Data service for applications to use. As a use case, a semantic portal WarSampo providing six different perspectives to the war based on events is presented.

This paper presents the WarSampo system for publishing collections of heterogeneous, distributed data about the Second World War on the Semantic Web. WarSampo is based on harmonizing massive datasets using event-based modeling, which makes it possible to enrich datasets semantically with each others’ contents. WarSampo has two components: First, a Linked Open Data (LOD) service WarSampo Data for Digital Humanities (DH) research and for creating applications related to war history. Second, a semanticWarSampo Portal has been created to test and demonstrate the usability of the data service. The WarSampo Portal allows both historians and laymen to study war history and destinies of their family members in the war from different interlinked perspectives. Published in November 2015, theWarSampo Portal had some 20,000 distinct visitors during the first three days, showing that the public has a great interest in this kind of applications.

The faceted search paradigm is widely used in web applications, and there are various tools available for implementing it on the server side. In contrast, this paper presents an HTML based component tool on the client side that can be plugged on virtually any public SPARQL endpoint on the web, using only SPARQL API for data retrieval. To test and demonstrate the idea and the tool, application of the tool in a large in-use semantic portal is presented.

War history of the Second World War (WW2), humankind s largest disaster, is of great interest to both laymen and researchers. Most of us have ancestors and relatives who participated in the war, and in the worst case got killed. Researchers are eager to find out what actually happened then, and even more importantly why, so that future wars could perhaps be prevented. The darkest data of war history are casualty records---from such data we could perhaps learn most about the war. This paper presents a model and system for representing death records as linked data, so that 1) citizens could find out more easily what happened to their relatives during WW2 and 2) digital humanities (DH) researchers could (re)use the data easily for research.

This paper initiates and fosters work on publishing Linked Open Data about the Second World War. It is argued that the heterogeneous, distributed data about the international world war history makes a promising use case for semantic technologies. We hope that by making war data openly available we can learn from the past and promote peace.