Crosslingual%20Retrieval%20in%20an%20eLearning%20Environment

1
Crosslingual Retrieval in an eLearning Environment

• Cristina Vertan, Kiril Simov, Petya Osenova,
  Lothar Lemnitzer, Alex Killing, Diane Evans,
  Paola Monachesi
• http//www.lt4el.eu/
• Artificial Intelligence and Human-Oriented
  Computing
• (September 10-13, 2007 - Roma, Italy)

2
Framework

• EU-Project LT4eL Language Technology for
  eLearning (www.lt4el.eu) 12 Partners
• Learning objects in 9 Languages
• eLearning Test-System open source platform
  ILIAS (www.ilias.de/)
• Domain Computer Science for non CS specialists
• Services Keyword Extraction, Definition
  Detection, Semantic Search

3
Architecture (2)
User Profile
Place of multilinguality - real situation
Documents SCORM
Pseudo-Struct.
Basic XML
CONVERTOR 2
Documents SCORM
Pseudo-Struct
Documents HTML
Glossary
CONVERTOR 1
Metadata (Keywords) Ling. Annot XML
BG
EN
Documents User (PDF, DOC, HTML, SCORM,XML)
REPOSITORY
4
The Creation of LT4eL Ontology

• Processing of the keywords in LOs
• Formalization of the meanings definitions from
  Internet
• Linking to an upper ontology (DOLCE)
• Addition of new concepts
• Addition of relations
• Documentation
• Lexicons in 9 languages

5
Connection with other Ontologies
DOLCE (Guarinoal.)
WordNet
LT4EL
6
Ontology Example

• ltowlClass rdfabout"http//www.lt4el.eu/CSnCSWe
  bPage"gt
• ltrdfscommentgtA document (file) connected to the
• World Wide Web and viewable by anyone
  connected to
• the internet who has a web browser.lt/rdfscomm
  entgt
• ltrdfscommentgtHyper CSnCS
• http//www.lt4el.eu/CSnCSTextFilelt/rdfs
  commentgt
• ltrdfscommentgtEqual WN20 ENG20-05964213-nlt/rdf
  scommentgt
• ltrdfscommentgtID id1757lt/rdfscommentgt
• ltrdfssubClassOfgt
• ltowlClass rdfabout"http//www.lt4el.eu/CSn
  CSTextFile"/gt
• lt/rdfssubClassOfgt
• lt/owlClassgt

7
Lexicon Entry

• ltentry id"id60"gt
• ltowlClass rdfabout"http//www.lt4el.eu/CSnCS
  BarWithButtons"gt
• ltrdfssubClassOfgt
• ltowlClass rdfabout"http//www.lt4el.eu/C
  SnCSWindow"/gt
• lt/rdfssubClassOfgt
• lt/owlClassgt
• ltdefgtA horizontal or vertical bar as a part of
  a window,
• that contains buttons, icons.lt/defgt
• lttermg lang"nl"gt
• ltterm shead"1"gtwerkbalklt/termgt
• lttermgtbalklt/termgt
• ltterm type"nonlex"gtbalk met knoppenlt/termgt
• lttermgtmenubalklt/termgt
• lt/termggt
• lt/entrygt

8
Ontology and Multilingual Data
Ontology
Lexicons
Documents
DT
DT
DE
DE
EN
EN
9
Multilingual, Semantic Document Retrieval

• Starting points
• A multilingual document collection
• An ontology including a domain ontology on the
  domain of the documents
• Concept lexicalisations in various languages
• Annotation of concepts in the documents

10
Goals of the Approach

• Improved access to documents
• Find docs that would not be found by simple text
  search
• Multilinguality
• One implementation for multiple languages
• Crosslinguality
• Retrieve documents in languages other than
  language of the query or ontology presentation

11
Outline of Search Procedure

• The User
• Submits a free text query
• Sees document list
• A list of documents is displayed with some meta
  information, for example
• title length original language
• keywords and concepts that are common to both the
  query and the document
• other keywords and concepts that are related to
  the document but not to the query
• Sees concepts for refining search
• Concepts related to the search query ? starting
  point for browsing
• No related concepts from search query ? root of
  ontology starting point

12
Outline of Search Procedure

• Views documents
• User looks into the documents from the list and
  estimates their relevance
• Browses ontology
• Entry point depends on the initial query
• Selects concepts
• Concepts are used for query refinement
• Selects search option
• The search option is about how to use the
  ontology fragments for search

13
Outline of Search Procedure

• Sees new document list
• A new list of documents is displayed, based only
  on ontological search
• Sees updated concept browsing units
• Concepts that are common to the found
  documentsExample Concept Report ? Some
  documents about academic writing ? Concept
  Publication
• Repeats steps from step 5 (Browse ontology)
• User selects another set of related concepts and
  submits it as the search key, etc

14
Integration in ILIAS
15
Conclusion and Future Work

• We are ready to
• Compare different searches over LOs
• Tune parameters of the searches
• Validate the user added value of the provides
  services
• Add relations and extend the search
• Provide context of the result from the search