模糊描述逻辑知识库查询蕴涵的判定方法

大规模领域本体的快速发展对语义Web领域的数据访问提出了更高的要求,而基本的本体推理服务已不能满足数据密集型应用中处理复杂查询(主要是合取查询)的迫切需要.为此,大量的研究工作集中在本体和描述逻辑知识库合取查询算法的设计实现上,并开发出了很多知识库存储和查询的实用工具.近来模糊本体和模糊描述逻辑的研究,特别是它们在处理语义Web中模糊信息方面,得到了广泛关注.文中重点研究了模糊SH这一族极富表达能力的描述逻辑知识库的合取查询问题,提出了相应的基于推演表的算法,证明了算法对于f-SHOIQ的真子逻辑的可靠性、完备性和可终止性.证明了算法对于f-SHOIQ是可靠的,并分析了导致算法不可终止的原因.对于该问题的数据复杂度,证明了当查询中不存在传递角色时其严格的CONP上限.对于联合复杂度,汪明了算法关于知识库和查询大小的CO3NEXPTIME时间复杂度上限.     

Integration of complex archeology digital libraries: An ETANA-DL experience

In this paper, we formalize the digital library (DL) integration problem and propose an overall approach based on the 5S (streams, structures, spaces, scenarios, and societies) framework. We then apply that framework to integrate domain-specific (archeological) DLs, illustrating our solutions for key problems in DL integration. An integrated Archeological DL, ETANA-DL, is used as a case study to justify and evaluate our DL integration approach. More specifically, we develop a minimal metamodel for archeological DLs within the 5S theory. We implement the 5SSuite tool set to cover the process of union DL generation, including requirements gathering, conceptual modeling, rapid prototyping, and code generation. 5SSuite consists of 5SGraph, 5SGen, and SchemaMapper, each of which plays an important role in DL integration. We also propose an approach to integrated DLs based on the 5S formalism, which provides a systematic method to design and implement DL exploring services.     

The foundational model of anatomy in OWL: Experience and perspectives

We present the method developed for migrating the Foundational Model of Anatomy (FMA) from its representation with frames in Protégé to its logical representation in OWL and our experience in reasoning with it. Despite the extensive use of metaclasses in Protégé, it proved possible to convert the FMA from Protégé into OWL DL, while capturing most of its original features. The conversion relies on a set of translation and enrichment rules implemented with flexible options. Unsurprisingly, reasoning with the FMA in OWL proved to be a real challenge, due to its sheer size and complexity, and raised significant inference problems in terms of time and memory requirements. However, various smaller versions have been successfully handled by Racer. Some inconsistencies were identified and several classes reclassified. The results obtained so far show the advantage of OWL DL over frames and, more generally, the usefulness of DLs reasoners for building and maintaining the large-scale biomedical ontologies of the future Semantic Web.     

Towards a digital library theory: a formal digital library ontology

Digital libraries (DLs) have eluded definitional consensus and lack agreement on common theories and frameworks. This makes comparison of DLs extremely difficult, promotes ad-hoc development, and impedes interoperability. In this paper we propose a formal ontology for DLs that defines the fundamental concepts, relationships, and axiomatic rules that govern the DL domain, therefore providing a frame of reference for the discussion of essential concepts of DL design and construction. The ontology is an axiomatic, formal treatment of DLs, which distinguishes it from other approaches that informally define a number of architectural variants. The process of construction of the ontology was guided by 5S, a formal framework for digital libraries. To test its expressibility we have used the ontology to create a taxonomy of DL services and to reason about issues of reusability, extensibility, and composability. Some practical applications of the ontology are also described including: the definition of a digital library services taxonomy, the proposal of a modeling language for digital libraries, and the specification of quality metrics to evaluate digital libraries. We also demonstrate how to use the ontology to formally describe DL architectures and to prove some properties about them, thus helping to further validate the ontology.