We consider the following query answering problem: Given a Boolean conjunctive query and a theory in the Horn loosely guarded fragment, the aim is to determine whether the query is entailed by the theory. In this paper, we present a resolution decision procedure for the loosely guarded fragment, and use such a procedure to answer Boolean conjunctive queries against the Horn loosely guarded fragment. The Horn loosely guarded fragment subsumes classes of rules that are prevalent in ontology-based query answering, such as Horn ALCHOI and guarded existential rules. Additionally, we identify star queries and cloud queries, which using our procedure, can be answered against the loosely guarded fragment.

中文翻译：

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确定松散保护的片段并使用分辨率查询其角片段

我们考虑以下查询回答问题：给定一个布尔连接查询和 Horn 松散保护片段中的一个理论，目的是确定该查询是否包含在该理论中。在本文中，我们提出了松散保护片段的解析决策过程，并使用这样的过程来回答针对 Horn 松散保护片段的布尔连接查询。Horn 松散保护的片段包含在基于本体的查询回答中普遍存在的规则类别，例如 Horn ALCHOI 和受保护的存在规则。此外，我们确定了明星查询和云查询，使用我们的程序，可以针对松散保护的片段回答这些查询。