1 / 15

Consistency Checking of RM-ODP Specifications

Consistency Checking of RM-ODP Specifications. Kenneth Baclawski Mieczyslaw Kokar Jeffrey Smith Jerzy Letkowski. Themes. Consistency Checking Fundamental requirement Techniques for checking consistency Demonstration of ConsVISor Category Theory Component framework for logical theories

kawena
Télécharger la présentation

Consistency Checking of RM-ODP Specifications

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Consistency Checking of RM-ODP Specifications Kenneth Baclawski Mieczyslaw Kokar Jeffrey Smith Jerzy Letkowski

  2. Themes • Consistency Checking • Fundamental requirement • Techniques for checking consistency • Demonstration of ConsVISor • Category Theory • Component framework for logical theories • Component composition • Refinement for code generation

  3. Logical Consistency • A fundamental requirement of any rigorous formalization • Definition: there exists a non-trivial model of the theory. • If a theory is inconsistent then every logical statement is true. • Inconsistency is dangerous for autonomous agents!

  4. owns type type type Wendy Wanda owns Logical Reasoning Fish Person Type constraint violation: The range of owns is Fish. Mermaid? OR There is no inconsistency: Wanda is a fish!

  5. major (0,1) type type type major Chemistry George equivalentTo Computer Science major Department Student Cardinality constraint violation: George can’t have two majors OR There is no inconsistency: Computer Science = Chemistry

  6. Checking Consistency • Consistency checking is very hard. • Church showed that first-order logic is only semi-decidable. • ConsVISor uses two concurrent strategies: • Warn about possible inconsistencies. This part is in Prolog and Java. If none, then consistent. • Use the SNARK theorem prover to find true inconsistencies. This need not terminate.

  7. Inconsistencies • Manual consistency checking is difficult. • It is very hard to determine the consequences of a set of axioms just by looking at them. • Multiple viewpoints increase the difficulty. • Translation may introduce inconsistency. • Inconsistent languages: • Resource Description Framework (RDF) • DARPA Agent Markup Language (DAML) • Knowledge Interchange Format (KIF)

  8. Category Theory: Specware • Category theory furnishes a formal component framework for logical theories. • Specification morphisms are more powerful than the include mechanism. • Specifications are intensional. • Specifications can be refined to be progressively more detailed.

  9. Category of Specifications • A category consists of objects and morphisms. • An object is a formal specification (spec) consisting of sorts, operations, axioms and theorems. Each spec is a logical theory. • A morphism is a mapping of specs: • Sorts are mapped to sorts • Operations are mapped to operations. • Axioms and theorems map to theorems.

  10. One-Sort Spec One-Sort Spec Water Vehicle Water Craft Land Vehicle Land Vehicle Composed Spec Component Composition • Components can be composed by using the colimit mechanism. Vehicle Spec Amphibian Spec

  11. Template instantiation Vehicle Spec Linked List of Vehicles One-Sort Spec Linked List Spec Importing and Templates Import specification Vehicle Spec Linked List and Vehicle Linked List Spec

  12. Web Links • This presentation is available online at <Baclawski.com/woodpecker.ppt> • Versatile Information Systems (VIS) Web site <vis.home.mindspring.com> • Inconsistent languages (on VIS Web site): • RDF <www.w3.org/rdf> • DAML <www.daml.org> • KIF <logic.stanford.edu/kif>

  13. More Web links • Ontology-based computing talk <Baclawski.com/gbctalk.ppt> • Specware and Slang <www.kestrel.edu> • SNARK automated theorem prover <www.ai.sri.com/~stickel/snark.html>

More Related