Introduction to. Ontological Engineering

Transcription

1 Introduction to Asunción Gómez-Pérez Credits to: Mari Carmen Suárez -Figueroa Boris Villazón-Terrazas Elena Montiel Guadalupe Aguado Mauricio Espinoza Work distributed under the license Creative Commons Attribution-Noncommercial-Share Alike 3.0 1

2 Index Introduction NeOn Methodology Scenarios in Ontology Building Guidelines for Ontology Specification Quick Search of Existing Knowledge Resources Ontology development project Planning Non-Ontological Resource Reuse and Re-engineering Ontology Reuse Creating the Ontology Model Localizing the Ontology Conclusions

3 Motivation Non-Ontological Resource Reuse Merging Ontological Resources Ontological Resource Reuse Localizing Ontological Resources Reusing Ontology Design Patterns Ontological Resource Re -engineering.. Restructuring Ontological Resources Non-Ontological Resource Re -engineering 3

4 Motivation In our team, we want to build an OWL ontology in the pharmaceutical domain, but we want to use several pharmaceutical standards in XML and classification schemes in our own format. Classical Non Ontological Resource Reuse Non Ontological Resource Reengineering

5 Motivation In our team, we want to build an ontology about the human resources management domain. The ontology should include information about occupations and activity sectors, data must be kept in the original DBs, and we want to have the ontology in several natural languages. Classical Ontology Mappings Ontology-DB mapping Ontological Resource Reuse Re-engineering Non-ontological resources Localizing Ontological Resources 5

6 Building ontologies in the 90s Methodologies for building single ontologies Uschold and King s method Grüninger and Fox s methodology KACTUS approach METHONTOLOGY SENSUS method On-To-Knowledge DILIGENT Ontology learning approaches for building ontologies from structured, semi-structured and non-structured data Are not integrated with current methodologies Mainly from non-structured data using NLP techniques

7 Current situation Reuse of knowledge-aware resources Ontologies are built collaboratively Ontologies are connected in ontology networks Multilingual features Ontology Development Process 7

8 Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri Knowledge Resources O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 5 NeOn Scenarios Ontological Resource Reuse Non Ontological Resource Reuse Non Ontological Resource Reengineering Ontology Design Pattern Reuse 7 3 Ontological Resource Reengineering 5 O. Aligning O. Merging 5 Alignments 1 O. Specification Scheduling O. Conceptualization O. Formalization O. Implementation 9 O. Localization 8 Ontology Restructuring (Pruning, Extension, Specialization, Modularization) RDF(S) OWL Flogic 8 1,,3,,5,,7,8, 9 Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Ontological Configuration Engineering Management; Evaluation 8 (V&V); A. Gómez Assessment Pérez, M.C. Suarez de Figueroa, B. Villazón, E.Montiel, G. Aguado, M. Espinoza

9 NeOn Methodology Process and activities covered: Ontology Specification Scheduling Non-Ontological Resource Reuse Non-Ontological Resource Re-engineering Reuse General Ontologies Reuse Domain Ontologies Reuse Ontology Statements Reuse Ontology Design Patterns All processes and activities are described with: A filling card A workflow Examples 9

10 Looking for an European Employment r ES q ES p ES EURES o ES ES (Int) n ES m ES Catalonia l ES ES (Es) Lombard ES (It) i ES a ES h ES LEGENDA ES Employment Service b ES Job Seeker s Candidacy Employer Job Vacancy c ES 10 d ES Wallonia e ES ES (Be) f ES Private g ES ES (Int)

11 Helping Job Seekers on their way r ES q ES p ES EURES o ES ES (Int) Local Matching algorithm n ES m ES Catalonia l ES ES (Es) Local Matching algorithm Lombard ES (It) i ES LEGENDA Requester ES Responding ES ES not involved a ES b ES Job Seeker s Candidacy Employer Job Vacancy c ES 11 d ES Wallonia e ES ES (Be) Local Matching algorithm f ES h ES Private g ES ES (Int) Local Matching algorithm

12 Key issues Reuse of proprietary knowledge-aware resources Heterogeneity Terms are in different languages Different conceptualization (different ways of organizing job categories) Different DB schemas Data must be kept in the original sources and in their own language. 1

13 Key aspects of Ontologies Single versus network of ontologies? Are ontologies built from scratch or reusing knowledge-aware resources? Are mappings used for solving conceptual mistmaches? Instances Where are the data/instances? Instances are in the ontology Instances are in RDF files independently of the ontology Data are kept in the original sources Are instances distributed or centralized? Have instances a very high rate of changes? Heterogeneous provenance of instances Degrees of data quality Permissions 13

14 Centralized network of ontologies where data are distributed Federated network of ontologies where data are distributed Ms Ms Ms Ms Ms Ms Ms Ms Ms Ms Ms Ms Ms Ms Ms 1. Build a reference ontology. Build mappings between the reference ontology and the data sources 1. Build a reference ontology for the domain. Build local ontologies 3. Build mappings between the core and local ontologies. Build mappings between the local ontologies and the data sources 1

15 Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri Knowledge Resources O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 NeOn Methodology 5 Ontological Resource Reuse Non Ontological Resource Reuse Non Ontological Resource Reengineering Ontology Design Pattern Reuse 7 3 Ontological Resource Reengineering 5 O. Aligning O. Merging 5 Alignments 1 O. Specification Scheduling O. Conceptualization O. Formalization O. Implementation 9 O. Localization 8 Ontology Restructuring (Pruning, Extension, Specialization, Modularization) RDF(S) OWL Flogic 15 1,,3,,5,,7,8, 9 Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Ontological Configuration Engineering Management; Evaluation 15 (V&V); A. Gómez Assessment Pérez, M.C. Suarez de Figueroa, B. Villazón, E.Montiel, G. Aguado, M. Espinoza

16 Ontology Requirement Specification Document Ontology Requirements Specification Document Template 1 P u r p o s e Software developers and ontology practitioners should include in this slot the purpose of the ontology S c o p e Software developers and ontology practitioners should include in this slot the scope of the ontology 3 L e v e l o f F o r m a l i t y Software developers and ontology practitioners should include in this slot the level of formality of the ontology I n t e n d e d U s e r s Software developers and ontology practitioners should include in this slot the intended users of the ontology 5 I n t e n d e d U s e s Software developers and ontology practitioners should include in this slot the intended uses of the ontology G r o u p s o f C o m p e t e n c y Q u e s t i o n s Software developers and ontology practitioners should include in this slot the groups of competency questions and their answers, i n c l u d i n g p r i o r i t i e s f o r e a c h g r o u p 7 P r e - G l o s s a r y o f T e r m s T e r m s Software developers and ontology practitioners should include in this slot the list of terms included in the CQs and their frequencies O b j e c t s Software developers and ontology practitioners should include in this slot a list of objects and their frequencies 1

17 Ontology Specification 1 Purpose The purpose of building the Reference Ontology is to provide a consensual knowledge model of the employment domain that could be used by public e-employment services (PES). Scope 3 The ontology has to focus just on the ICT (Information and Communication Technology) domain. The level of granularity is directly related to the competency questions and terms identified. Intended Users Level of Formality Candidate who is unemployed and searching for a job or The searching ontology another has to occupation be implemented for immediate in WSML or language future purposes. Employer who needs more human resources. 3. Public or private employment search service which offers services to gather CVs or job postings and to prepare some data 5 and statistics.. National Intended and Uses Local Governments which want to analyze the situation on the employment market in their countries and prepare documents on employment, social and educational policy. 1. Publish CV. Job seeker places his/her CV on the PES 5. European Portal. Commission and the governments of EU countries which. want Publish to analyze Job Offer. the An statistics Employer and places prepare a Job international Offer agreements the PES and Portal. documents on the employment, social and educational 3. Search policy. for Job Offers. The Employer looks for candidates for the Job Offer through PES Portal.. Search for Employment information. Job Seeker looks for of general information about employment in a given location at the PES Portal. A. Gómez 5. Provide Pérez, Job M.C. Statistics. Suarez de The Figueroa, PES Portal B. Villazón, provides E.Montiel, G. Aguado, M. Espinoza employment statistics to the Job Seeker and Employer.

18 Ontology Specification: Identify requirements using competency questions 18

19 Ontology Specification: Group requirements. 19

20 Ontology Specification. The Ontology Requirement Specification Document 0

21 Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri Knowledge Resources O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 NeOn Methodology 5 Ontological Resource Reuse Non Ontological Resource Reuse Non Ontological Resource Reengineering Ontology Design Pattern Reuse 7 3 Ontological Resource Reengineering 5 O. Aligning O. Merging 5 Alignments 1 O. Specification Scheduling O. Conceptualization O. Formalization O. Implementation 9 O. Localization 8 Ontology Restructuring (Pruning, Extension, Specialization, Modularization) RDF(S) OWL Flogic 1 1,,3,,5,,7,8, 9 Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Ontological Configuration Engineering Management; Evaluation 1 (V&V); A. Gómez Assessment Pérez, M.C. Suarez de Figueroa, B. Villazón, E.Montiel, G. Aguado, M. Espinoza

22 Searching Resources Use the terminology from the ORSD Find resources covering the terminology Knowledge Resources Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL Where: - Internet - Standardization bodies (ISO, ) - Intranet of the organization - Ontology Registries

23 Catalog/ID Glossary Informal is-a Informal is-a Thesaurus Thesaurus Catalog/ID Implicit knowledge coded in numbers XX-YY-ZZ : transportation 01: road 0: 3-lines highway 3

24 ISO 17 (currencies) ISO 31 (countries) A Method for Reusing and Ontological Re-engineering Engineering Non-Ontological Resources for Building

25 Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri Knowledge Resources O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 NeOn Methodology 5 Ontological Resource Reuse Non Ontological Resource Reuse Non Ontological Resource Reengineering Ontology Design Pattern Reuse 7 3 Ontological Resource Reengineering 5 O. Aligning O. Merging 5 Alignments 1 O. Specification Scheduling O. Conceptualization O. Formalization O. Implementation 9 O. Localization 8 Ontology Restructuring (Pruning, Extension, Specialization, Modularization) RDF(S) OWL Flogic 5 1,,3,,5,,7,8, 9 Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Ontological Configuration Engineering Management; Evaluation 5 (V&V); A. Gómez Assessment Pérez, M.C. Suarez de Figueroa, B. Villazón, E.Montiel, G. Aguado, M. Espinoza

26 Selection of Ontologies Search ontologies Compare ontologies in the same domain using a set of criteria Assess if the ontologies cover the set of competency questions Select the best ontology based on Coverage of the domain Expressivity of the Implementation language

27 Searching Ontologies in Watson Ontology Requirement Specification Document The NeOn methodology includes guideliness for reusing statements 7

28 Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri Knowledge Resources O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 NeOn Methodology 5 Ontological Resource Reuse Non Ontological Resource Reuse Non Ontological Resource Reengineering Ontology Design Pattern Reuse 7 3 Ontological Resource Reengineering 5 O. Aligning O. Merging 5 Alignments 1 O. Specification Scheduling O. Conceptualization O. Formalization O. Implementation 9 O. Localization 8 Ontology Restructuring (Pruning, Extension, Specialization, Modularization) RDF(S) OWL Flogic 8 1,,3,,5,,7,8, 9 Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Ontological Configuration Engineering Management; Evaluation 8 (V&V); A. Gómez Assessment Pérez, M.C. Suarez de Figueroa, B. Villazón, E.Montiel, G. Aguado, M. Espinoza

29 Gantt chart for your project. Waterfall model 9

30 Reuse and Re-engineering + Incremental Slide 30 30

31 Motivation I want to transform my adjacency list-based classification into an ontology 31

32 Types of non-ontological resources Non-Ontological Resources are knowledge-aware resources whose semantics have not been formalized yet by means of an ontology 3

33 Types of non-ontological resources 33

34 Approaches to transform resources into ontologies ABox TBox Population 3

35 Approach for Re-engineering Non-Ontological Resources 35

36 Technological support PR-NOR library at the ODP Portal NORO: a Library for Transforming Non-Ontological Resources to Ontologies 3

37 Pattern based approach for re-engineering non ontological resources ISCO-88 (COM) International Standard Classification of Occupations (for European Union purposes) FOET Classification of fields of education and training NACE Statistical Classification of Economic Activities in the European Community Pattern for re-engineering a classification scheme modelled with a Path Enumeration Data Model ISO 31 English country names and code elements Pattern for re-engineering a classification scheme modelled with a Snowflake Data Model ISTAT Italian Geography Standard Pattern for re-engineering a classification scheme modelled with an Adjacency List Data Model 37

38 Knowledge Resource Re-engineering and Aggregation. ISO 31-1 (XML) <ISO_31-1_Entry> <ISO_31-1_Country_name>SPAIN</ISO_31-1_Country_name> <ISO_31-1_Alpha-_Code_element>ES</ ISO_31-1_Alpha-_Code_element> </ISO_31-1_Entry> Regions Table (Eures Oracle DB) Excerpt of the Geography Ontology Ontology model Location subclass-of Country has region Region 38 Spain Cataluña Canarias Ontology instances Galicia Andalucía

39 NeOn Scenarios Knowledge Resources Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 5 Ontological Resource Reuse 1 Non Ontological Resource Reuse Non Ontological Resource Reengineering O. Specification O. Conceptualization O. Formalization O. Implementation O. Localization 9 Ontology Design Pattern Reuse Ontological Resource Reengineering Ontology Restructuring (Pruning, Extension, Specialization, Modularization) Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Configuration Management; Evaluation (V&V); Assessment 39 5 RDF(S) OWL Flogic 1,,3,,5,,7,8, 9 O. Aligning O. Merging 5 Alignments

40 Ontological Resource Reuse Process Reuse Common Ontologies Reuse Domain Ontologies Reuse ODPs by naive users Reuse Ontology Statements 0 Slide 0

41 Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri Knowledge Resources O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 NeOn Methodology 5 Ontological Resource Reuse Non Ontological Resource Reuse Non Ontological Resource Reengineering Ontology Design Pattern Reuse 7 3 Ontological Resource Reengineering 5 O. Aligning O. Merging 5 Alignments 1 O. Specification Scheduling O. Conceptualization O. Formalization O. Implementation 9 O. Localization 8 Ontology Restructuring (Pruning, Extension, Specialization, Modularization) RDF(S) OWL Flogic 1 1,,3,,5,,7,8, 9 Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Ontological Configuration Engineering Management; Evaluation 1 (V&V); A. Gómez Assessment Pérez, M.C. Suarez de Figueroa, B. Villazón, E.Montiel, G. Aguado, M. Espinoza

42 Conceptualization: Modular approach for ontology construction Reusability - Usability + Application Domain O. : Job Seeker, Job Offer Domain O.: Economic Activity, Occupation, Education, Skill, Driving License, Compensation, Labour Regulatory, Competence + General/Common Ontologies: Time, Geography, Language Representation Ontology: WSML -

43 EURES Reference Ontology CEF ISO 39 ISCO-88 COM ONET EURES LE FOREM + BLL + EURES has contract type / is associated to Skill Ontology Language Ontology Occupation Ontology EURES ISO 31 subclass-of ISO 17 Labour Regulatory Ontology Competence Ontology Compensation Ontology European Legislation has work condition / is associated to has contract type / is associated with has work condition / is associated with requires competence / is associated with subclass-of Driving License Ontology Job Offer Ontology 3 is located in / is associated with has activity sector / is associated with has salary / is associated to has activity sector / is associated with Economic Activity Ontology has activity sector / is associated with Job Seeker Ontology has location / is associated with has nationality from / is nation of resides in / is residence of Education Ontology NACE Rev. 1.1 has date of birth / is date of birth of has begin date / is begin date of Geography Ontology Time Ontology FOET ISCED97 DAML Time Ontology Ad hoc wrapper External Sources

44 Details of the ontology has mother language / is mother tongue of speaks / is spoken by has job category / is associated with has education / is education of Job Seeker Candidacy Objective ICT Objective has job category / is associated with has candidacy/ belongs to has objective / belongs to subclass-of has competence / is competence of Language has nationality from / is nation of has job category is associated with resides in / is residence of has work experience / belongs to Offered Work Experience Computing Professionals Occupation has work condition / is associated to has contract type / is associated to subclass-of has compensation / is associated with / is associated to has location Competence Work Condition Contract Type Compensation Country Location Sector has activity sector / is associated with has activity sector / is associated with has activity sector / is associated with has job category/ is associated with Education has compensation / is associated with Requested Work Experience has location / is location of is located in / is associated with is associated with / requires work experience has activity sector / is associated with has job category/ is associated with Organization has job vacancy/ belongs to Job Vacancy Vacancy ICT Vacancy has job category / is associated with requires education / is associated with requires competence / is associated with has work condition / is associated with has contract type / is associated with has vacancy/ belongs to subclass-of

45 Non Ontological Resources Glossaries Classification Schemas Dictionaries Taxonomies Lexicons Thesauri Knowledge Resources O. Design Patterns Ontological Resources O. Repositories and Registries Flogic RDF(S) OWL 3 NeOn Methodology 5 Ontological Resource Reuse Non Ontological Resource Reuse Non Ontological Resource Reengineering Ontology Design Pattern Reuse 7 3 Ontological Resource Reengineering 5 O. Aligning O. Merging 5 Alignments 1 O. Specification Scheduling O. Conceptualization O. Formalization O. Implementation 9 O. Localization 8 Ontology Restructuring (Pruning, Extension, Specialization, Modularization) RDF(S) OWL Flogic 5 1,,3,,5,,7,8, 9 Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Ontological Configuration Engineering Management; Evaluation 5 (V&V); A. Gómez Assessment Pérez, M.C. Suarez de Figueroa, B. Villazón, E.Montiel, G. Aguado, M. Espinoza

46 Ontology Localization

47 LabelTranslator NeOn plugin Slide 7 7

48 Conclusions 1. The NeOn methodology gives 1. detailed guidelines for building ontologies. facilitates the reuse and reengineering of non ontological resources into ontologies. The reuse of non-ontological resources that have been reached some degree of consensus in a community allows the development of ontologies easier and quicker 8

49 Handbook on the NeOn Methodology 9 Slide 9

50 Executive Chapter Summaries are available at the NeOn Web Site Slide Slide 50