A semantic reasoner, reasoning engine, rules engine, or simply a reasoner, is a piece of software able to infer logical consequences from a set of asserted facts or axioms. The notion of a semantic reasoner generalizes that of an inference engine, by providing a richer set of mechanisms to work with. The inference rules are commonly specified by means of an ontology language, and often a description language. Many reasoners use first-order predicate logic to perform reasoning; inference commonly proceeds by forward chaining and backward chaining. There are also examples of probabilistic reasoners, including Pei Wang's non-axiomatic reasoning system, Novamente's probabilistic logic network, which tip their hat to reasoning Bayesian networks, and Pronto - probabilistic description logic reasoner.

[edit] Semantic reasoners, etc.

Existing semantic reasoners and related software:

• Bossam (software), an RETE-based rule engine with native supports for reasoning over OWL ontologies, SWRL ontologies, and RuleML rules.
• DLog, Resolution based Description Logic ABox reasoner that translates to Prolog.
• FaCT, a description logic (DL) classifier.
• FaCT++, the new generation of FaCT OWL-DL reasoner.
• Hoolet, reasons over OWL-DL ontologies by translating them to full first-order logic and then applying a first-order theorem prover.
• Jena (framework), an open source semantic web framework for Java which includes a number of different semantic reasoning modules.
• KAON2 is an infrastructure for managing OWL-DL, SWRL, and F-Logic ontologies.
• OWLIM, a high-performance semantic repository developed in Java and available in two versions: free SwiftOWLIM and commercial BigOWLIM. Supports a subset of OWL-Lite semantics, which can be configured through rule-set definition and selection.^[1]
• Pellet, an open-source Java OWL DL reasoner.
• RacerPro, a semantic web reasoning system and information repository
• SHER, a scalable Pellet-backed OWL DL reasoner.
• SweetRules, an integrated set of tools for Semantic web rules and ontologies.

[edit] Reasoner comparison

[edit] See also

• Business rules engine
• Expert systems

[edit] External links

• SPARQL Query Language for RDF
• DIG description logic reasoner interface
• Introduction to Description Logics DL course by Enrico Franconi, Faculty of Computer Science, Free University of Bolzano, Italy

[edit] References