The W3C Web Ontology Language (OWL) is a powerful knowledge representation formalism at the basis of many semantic-centric applications. Since its unrestricted usage makes reasoning undecidable already in case of very simple tasks, expressive yet decidable fragments have been identified. Among them, we focus on OWL 2 RL, which offers a rich variety of semantic constructors, apart from supporting all RDFS datatypes. Although popular Web resources - such as DBpedia - fall in OWL 2 RL, only a few systems have been designed and implemented for this fragment. None of them, however, fully satisfy all the following desiderata: (i) being freely available and regularly maintained; (ii) supporting query answering and SPARQL queries; (iii) properly applying the sameAs property without adopting the unique name assumption; (iv) dealing with concrete datatypes. To fill the gap, we present DaRLing, a freely available Datalog rewriter for OWL 2 RL ontological reasoning under SPARQL queries. In particular, we describe its architecture, the rewriting strategies it implements, and the result of an experimental evaluation that demonstrates its practical applicability.

中文翻译：

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DaRLing：SPARQL 查询下 OWL 2 RL 本体推理的 Datalog 重写器

W3C Web Ontology Language (OWL) 是一种强大的知识表示形式，它是许多以语义为中心的应用程序的基础。由于其不受限制的使用使得推理在非常简单的任务中已经无法确定，因此已经确定了表达性但可确定的片段。其中，我们专注于 OWL 2 RL，它除了支持所有 RDFS 数据类型外，还提供了丰富的语义构造函数。尽管流行的 Web 资源（例如 DBpedia）属于 OWL 2 RL，但只有少数系统为此片段设计和实现。然而，它们都不能完全满足以下所有要求：（一世）可免费使用并定期维护；(二)支持查询回答和 SPARQL 查询；㈢正确应用与...一样不采用唯一名称假设的属性；(四)处理具体的数据类型。为了填补空白，我们提出宠儿，一个免费提供的 Datalog 重写器，用于 SPARQL 查询下的 OWL 2 RL 本体推理。特别是，我们描述了它的架构、它实现的重写策略，以及展示其实际适用性的实验评估结果。