The features of RacerPro Version 1.9:
Among others the RacerPro system offers the following features:
- Expressive query language nRQL allows for powerful queries that are efficiently processed (many users of older description logic systems have missed server-based conjunctive queries in previous versions of Racer).
- RacerPro 1.9 provides for means of resource bounded computation, i.e., maximum query answering times can be specified.
- RacerPro 1.9 allows for resource-aware computation, i.e., query answering can be done in such a way that applications are instructed that retrieving additional tuples results in much more resources to be allocated. In other words: RacerPro takes care that “easy” answers are computed first and with minimum resources, however, RacerPro is a complete reasoner that informs the user application about a possible increase in computational resources (time and space).
- Extended support for OWL DL: RacerPro 1.9 supports OWL DL almost completely. In particular, compared to the previous version of Racer, datatype properties and annotation properties are now handled appropriately, and RacerPro's expressive query language nRQL handle both types of roles efficiently. There are still two limitations, however. First, individuals in class expressions (so-called nominals) are only approximated (for details and consequences see Chapter 5.1 of the User Guide). Note that individuals may adequately be processed in RacerPro using so-called ABoxes. Second, currently, RacerPro cannot process user-defined datatype types given as external XML Schema specifications (although all required datatypes of OWL DL are properly supported).
- RacerPro 1.9 does not employ the unique name assumption (see below) as required by OWL DL. UNA can be enabled globally, however, if efficiency is of utmost importance.
- The nRQL system also support a rule engine which provides for efficient and application-controlled ABox augmentation based on rules.
- A model-checking facility is integrated with nRQL as well. In this context, for instance, reasoning with qualitative spatial relations (e.g., RCC8) can be exploited as part of the query language.
- New graphical interface are available for RacerPro 1.9.
- Last but not least: RacerPro 1.9 provides many performance improvements and now offer support for some features not available in 1.7 (e.g., equivalence of roles, synonyms for individuals, datatype property roles, annotation property roles, etc.).
Structure of available Services
- Supported description logic: ALCQHIR+ also known as SHIQ
- OWL-DL without so called “nominals”
- access to OWL resources via integrated http client functionality
- processing of rules in a SWRL-based syntax by translating them into nRQL rules
- queries in OWL-QL are translated to nRQL (see RacerManager)
- DIG protocol via http/XML for client software such as Protégé
- native access from your application in Java or Lisp via IP sockets
- file I/O
- upcoming feature: complete OWL-DL implementation
- upcoming feature: SPARQL
Deployment options
- Back-end network server application
- File processor launched from command line interface
- User interaction via certain tools
- Part of user application when loaded as object code