On Mon, Jun 3, 2013 at 11:40 AM, Sawhney, Tarandeep Singh <[email protected]> wrote: > Hi > > I am new to stanbol and trying to understand its offerings. > > i have few questions, may i request to please provide your valuable inputs > so i understand things better and faster :-) Below questions are > very beginner level, so please bear. > > (1) When user edits marked up data and defines/disambiguates entities and > then saves it say from VIE type editor, what happens in the background ? > does RDF is stored in entityhub? text is stored in contenthub, then how > semantic indexes gets created and on what ? on text or on RDF metadata ? In > what scenarios we would need custom semantic indexes and not default > semantic indexes and how would they be created by the system ?
By default nothing of those. If you want to store Entities acknowledged by users in you will need to call the RESTful API of the Entityhub (typically a ManagedSite created for that reason). If you send documents to the contenthub (instead of the enhancer) the text and all enhancements will be stored and semantic indexed. In this case you can also get the RDF enhancement results via a RESTful service and display it in a VIE type editor. Documents sent to the Enhancer will not be included in the contenthub. > > (2) Is RDF stored in entityhub ? then what is stanbol fact-store and what > it stores ? OR entityhub uses fact-store ? The Entityhub does not store RDF. It stores Entities - in RDF language an entity is defined as an URI and all outgoing relation (similar to the definition of Linked Data). When loading RDF data to the Entityhub one need to consider that the Entityhub does not support bNodes. > > (3) What is stanbol SPARQL editor and does it run on top of entityhub ? It runs on top of Apache Clerezza. In case users do use a Clerezza TripleStore (ClerezzaYard) as backend for an Entityhub Site, you can also access those data via SPARQL. However typically the Apache Solr based implementation (SolrYard) is used by the Entityhub. In this case you can not perform SPARQL queries over the data in the Entityhub. The contenthub also stores the enhancement results in a Clerezza TripleStore. So you can perform SPARQL queries over the data in the Contenthub. > > (4) If i were to integrate something line Relfinder with stanbol, and > relfinder operates on RDF data, where it will get RDF data from ? Is it > from Entityhub ? As I stated above, you could use the ClerezzaYard to store the data of the Entityhub. However this would badly affect the performance of the Stanbol Enhancer when linking against those data (because Solr is much better with label based queries). An other option would be to use the Entityhub FieldQuery instead of SPARQL to obtain required information from the Entityhub. The FieldQuery interface works regardless of the storage backend. > > (5) What is semantic search ? if it is searching entities and relationships > (which are stored in entityhub in the form of linkeddata cloud) then what > is the role of semantic index and why it is said that content hub enables > semantic search ? What are the type of queries we can fire using semantic > search ? Relfinder tries to "find" relations between Entities. In that way it provides search / navigation support in the knowledge base. Semantic Search in Stanbol is defined as searches over the document space. So with the Contenthub you will be able to perform queries for all Documents that do mention a Person and a Place. > > (6) Can i pass pdf/word document to enhancer to generate metadata ? Yes. Just make sure to include the Apache Tika Engine [1] in your Enhancement Chain. [1] http://stanbol.apache.org/docs/trunk/components/enhancer/engines/tikaengine > > (7) how can i make enhancer extract my domain entities, what steps are > needed at high level ? [2] gives an good overview about that. Typically you can start by configuring a ManagedSite [3] and uploading your RDF data via the RESTful interface. Next you will need to configure an EntityhubLinkingEngine [4] for this ManagedSite. Finally you need to configure an Enhancement Chain (preferable a Weighted Chain) that includes tika, langdetect, opennlp-sentence, opennlp-token, opennlp-pos, opennlp-chunker and {your-entityhub-linking-engine}. After that your Enahncement Chain will be available in the RESTful Endpoint of the Stanbol Enhancer (enhancer/chain/{name-of-you-chain}). If you want to link against several vocabularies you can configure multiple ManagedSites and EntityhubLinkingEngine. If you want to have a single Enhancement Chain that links against all of those, just add all your EntityhubLinkingEngines to a single chain. best Rupert [2] http://stanbol.apache.org/docs/trunk/customvocabulary.html [3] http://stanbol.apache.org/docs/trunk/components/entityhub/managedsite.html [4] http://stanbol.apache.org/docs/trunk/components/enhancer/engines/entityhublinking > > thanks in advance > taran > > -- > > "This e-mail and any attachments transmitted with it are for the sole use > of the intended recipient(s) and may contain confidential , proprietary or > privileged information. If you are not the intended recipient, please > contact the sender by reply e-mail and destroy all copies of the original > message. Any unauthorized review, use, disclosure, dissemination, > forwarding, printing or copying of this e-mail or any action taken in > reliance on this e-mail is strictly prohibited and may be unlawful." -- | Rupert Westenthaler [email protected] | Bodenlehenstraße 11 ++43-699-11108907 | A-5500 Bischofshofen
