WSMO revisited

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WSMO - revisited

• SWSL phone conference, 17-06-2004
• Dieter Fensel
• Digital Enterprise Research Institute
• dieter.fensel_at_deri.org

2
Outline

• The new structure and main deliverables
• WSMO Working Group
• WSML Working Group
• WSMX Working Group
• Links to SWSL
• Rule language
• Choreography/Orchestration language

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Working Groups general overview

WSMO WG
A Conceptual Model for SWS
WSMX WG
WSML WG
A Formal Language for WSMO
An Execution Environment for WSMO
A Rule-based Language for SW
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WSMO WG

• Web site at http//www.wsmo.org/
• Chairs Christoph Bussler and Dieter Fensel.
• Mailing list for group members
• deri-wsmo_at_informatik.uibk.ac.at
• Mailing list for technical discussionsderi-wsmo-
  discussion_at_informatik.uibk.ac.at
• Contact dumitru.roman_at_deri.ie
• Activity sheet http//www.wsmo.org/2004/d6/d6.1/v
  1/Around 14 deliverables with defined editors
  and deadlines.
• Members http//www.wsmo.org/people.htmlCurrently
  58 members.
• Presentations http//www.wsmo.org/presentations.h
  tmlCurrently more than 45 presentations on
  related aspects.
• Current working drafts http//www.wsmo.org/2004/

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WSMO main deliverables

• Conceptual model for Semantic Web Services
• WSMO Standard (D2)
• WSMO Lite (D11)
• WSMO Full (D12)
• Choreography (D14) and Orchestration (D15)
• Not yet clearly defined.
• Intention use ASMs.
• Showcasing WSMO Primer (D3.1) and Case Studies
  (D3.2)
• Conceptual Comparison WSMO/OWL-S (D4.1)
• WSMO Tutorial (D17)
• WSMO in DIP(D19.1), KW(D19.2) and SEKT(D19.3)

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WSML WG

• Web site at http//www.wsmo.org/wsml
• Chair Dieter Fensel.
• Mailing list for group members
• deri-wsml_at_informatik.uibk.ac.at
• Mailing list for technical discussionsderi-wsmo-
  discussion_at_informatik.uibk.ac.at
• Contact dumitru.roman_at_deri.ie
• Activity sheet http//www.wsmo.org/2004/d6/d6.2/v
  1/Around 18 deliverables with defined editors
  and deadlines.
• Members http//www.wsmo.org/people.htmlCurrently
  16 members.
• Presentations http//www.wsmo.org/presentations.h
  tmlCurrently 13 presentations on related aspects
• Current working drafts http//www.wsmo.org/2004/

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WSML main deliverables

• WSML language
• WSML User language (D16.1)
• WSML/XML (An XML Syntax for WSML) (D16.3)
• F-logic/XML (An XML Syntax for F-logic) (D16.2)
• WSML OWL Syntax (D16.5) not yet defined
• Inferencing with WSML
• Inferencing support for SWS Proof Obligations
  (D5.1)
• Inferencing Support for Semantic Web Services
  Tools for Semantic Support (D5.2)
• Language Evaluation and Comparison (D8)
• Mapping to OWL-S (D4.3) not yet defined.
• Ontology Language API (D18)
• OWL-Lite (D20)

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WSMX WG

• Web site at http//www.wsmx.org/
• Chair Christoph Bussler.
• Mailing list for group members
• deri-wsmx_at_informatik.uibk.ac.at
• Mailing list for technical discussionsderi-wsmo-
  discussion_at_informatik.uibk.ac.at
• Contact michal.zaremba_at_deri.ie
• Activity sheet http//www.wsmo.org/2004/d6/d6.3/v
  1/Around 12 deliverables with defined editors
  and deadlines.
• Members http//www.wsmo.org/people.htmlCurrently
  33 members.
• Current working drafts http//www.wsmo.org/2004/

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WSMX main deliverables

• WSMO Editor (D9)
• WSMO Registry (D10)
• Overview and Scope of WSMX (D13.0)
• WSMX Conceptual Model (D13.1)
• WSMX Execution Semantics (D13.2)
• WSMX Mediation (D13.3)
• WSMX Architecture (D13.4)
• WSMX Implementation (D13.5) first version
  expected end of June, 2004.

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Links to SWSL

• Rule language effort
• Choreography and orchestration language

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Rule language effort

• Six points I want to make
• DL is an interesting subset of 1st order logic
• HL is an interesting subset of 1st order logic
• Full 1st order logic is an interesting language
• Pure logics are cumbersome tools for modeling
• SWRL is crap
• A useful rule language for the semantic web must
  follow a DL-minimalistic approach

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(1) DL is interesting

• because of its decidability/tractability
  properties
• spoken for the man on the street it is the
  fragment of logic that can be computationally
  explored around the existential quantifier.
• it is therefore worth to become standardized in
  OWL
• besides the fact that I do not like at all
  OWL-Lite which is an overkill,
• a smooth extension of RDFS would have been much
  more appropriate.
• Therefore we develope OWL-Flight (restricting
  OWL-Lite to DLP and extend it by RDF
  features).     

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(2) HL is interesting

• because of its decidability/tractability
  properties
• Spoken for the man on the street it is the
  fragment of logic that can be computationally
  explored around the all quantifier
• without function symbols it is decidable and
• with minimal-model semantics function symbols,
  non-monotinicity of negation, and even transitive
  closure (an extension of first order logic) can
  be expressed.
• It is therefore worth to become standardized by
  W3C, however, not in a way that destroy all
  features of rule languages by mixing it up too
  much with DL type of expressions.
• Therefore we develope OWL-Flight (restricting
  OWL-Lite to DLP and extend it by rule
  features).     
•       

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(3) First order logic is interesting

• In oposition to DLs and HLs it provides
  significant more flexibility in writing down
  required axioms.
• This language is not fully mechanizable in terms
  ofreasoning support, however,
• many interesting theorems can be proven and the
  theorem prover community has made significant
  progress over the last years.
• First order language could define the common
  umbrella, where DLs and HLs are sublanguages and
  unified.
• Therefore, we will redefine OWL-Full.

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(4) Pure logic is cumbersom

• Pure logics is a cumbersome tool for modeling
• Therefore, extensions like Flogic that allow
  quantification over classes and attributes are
  that helpful.
• W3C recommendations should care for this if they
  want to make their languages widely adopted.
• OWL-Flight provide these features.

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(5) I strongly dislike SWRL

• since it spoils the nice properties of rule
  languages for the price of defining the rule
  language as an extension of DLs.
• SWRL is meaningless since it defines a
  syntactical restriction of 1st order logic
  without any computational justification.
• SWRL is as undecidable and untractable as first
  order logic.
• Therefore, it is meaningless to syntactically
  restrict first order logic in that way.

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(6) A useful rule language for the semantic web
must follow a different approach

• It should emply the full power of the HL fragment
  and include DL features only in case they do not
  harm this language type.
• Therefore, a HL language should be defined as an
  extension of RDFS and/or OWL-Lite (where OWL Lite
  is reduced to an actual lite subset of DL).
• That is the rationale underlying OWL-Flight.

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Choreography and orchestration

• Choreography is about communication
• Orchestration is about task decomposition
• Both elements require the specification of
  dynamics
• We are using Abstract State Machines as a point
  of departure to formalize the basic principles
  for these languages.
• And we are very eager to learn from you!

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lt/ WSMO gt

• ltQAgt