Modelling and Reasoning in Metamodelling Enabled Ontologies

Ontologies are expected to play an important role in many application domains, as well as in software engineering in general. One problem with using ontologies within software engineering is that while UML, a widely used standard for specifying and constructing the models for a software-intensive system, has a four-layer metamodelling architecture, the standard Web Ontology Language (OWL) does not support reasoning over layered metamodels. OWL 2 provides simple metamodelling by using a punning approach, however, the interpretation function is different based on the context, which leads to non-intuitive results. The OWL FA Language has a well defined metamodelling architecture. However, there is no study and tool for supporting reasoning over OWL FA. In this paper, we discuss some reasoning tasks in OWL FA. We also introduce the OWL FA Tool kit, a simple tool kit for manipulating and reasoning with OWL FA.     

基于UML的本体建模研究

详细对比分析了OWL（Web Ontology Language）特性元素和UML特性元素及本体开发,在讨论OWL本体通过UML类图向面向对象语言转换方法的基础上,通过具体的示例进一步提出了一般多值域OWL属性本体建模的方法,并且说明使用该方法能够直观、清晰地进行本体建模,为下一步研究开发较成熟的软件产品奠定了良好的基础。     

SUPPORTING THE CAD STRUCTURAL DESIGN PROCESS WITH KNOWLEDGE-BASED TOOLS

We present in this article an architecture with its correspondent system implementation for the exploitation of semantic aspects in the computer assisted design of Steel Detailing Structures (Structural Design). Our architecture is based in a domain specific standardization effort called CIS/2 that was modeled from a knowledge point of view using an OWL (Ontology Web Language) compliant ontology.

As test case we present a collection of applications based in the proposed schema that were developed within the frame of an R&D project in which an actual structural engineering company participated as test user.     

Expressing inter-link constraints in OWL knowledge bases

Abstract: In this paper the Web Ontology Language (OWL) is examined to instantiate expert system knowledge bases intended for semantic Web applications. In particular, OWL is analyzed for expressing Unified Modeling Language (UML) representations that have been augmented with propositional logic asserted as inter‐link constraints. The motivation is ultimately to provide declarative propositional logic constraints that can be represented in UML and declaratively implemented using OWL and other constructs to realize semantic Web knowledge base repositories and databases to facilitate expert system applications. The results of this paper show that OWL is sufficient for capturing most inter‐link constraints asserted on generalization/specialization instances; however, OWL alone is inadequate for representing some inter‐link constraints asserted on associations. We propose enhancements to OWL via RDF extensions for the reification of associations into classes. These extensions mitigate all concerns that were identified in OWL as part of this study. The result is increased support of declarative constraint representations, which can be expressed in knowledge bases in the context of the semantic Web.     

Ontology-assisted automatic precise information extractor for visually impaired inhabitants

As the internet grows rapidly, millions of web pages are being added on a daily basis. The extraction of precise information is becoming more and more difficult as the volume of data on the internet increases. Several search engines and information fetching tools are available on the internet, all of which claim to provide the best crawling facilities. For the most part, these search engines are keyword based. This poses a problem for visually impaired people who want to get the full use from online resources available to other users. Visually impaired users require special aid to get?along with any given computer system. Interface and content management are no exception, and special tools are required to facilitate the extraction of relevant information from the internet for visually impaired users. The HOIEV (Heavyweight Ontology Based Information Extraction for Visually impaired User) architecture provides a mechanism for highly precise information extraction using heavyweight ontology and built-in vocal command system for visually impaired internet users. Our prototype intelligent system not only integrates and communicates among different tools, such as voice command parsers, domain ontology extractors and short message engines, but also introduces an autonomous mechanism of information extraction (IE) using heavyweight ontology. In this research we designed domain specific heavyweight ontology using OWL 2 (Web Ontology Language 2) and for axiom writing we used PAL (Protégé Axiom Language). We introduced a novel autonomous mechanism for IE by developing prototype software. A series of experiments were designed for the testing and analysis of the performance of heavyweight ontology in general, and our information extraction prototype specifically.     

Ontology-driven analysis of UML-based collaborative processes using OWL-DL and CPN

A key ingredient in system and organization modeling is modeling business processes that involve the collaborative participation of different teams within and outside the organization. Recently, the use of the Unified Modeling Language (UML) for collaborative business modeling has been increasing, thanks to its human-friendly visual representation of a rich set of structural and behavioral views, albeit its unclear semantics. In the meantime, the use of the Web Ontology Language (OWL) has also been emerging, thanks to its clearly-defined semantics, hence being amenable to automatic analysis and reasoning, although it is less human friendly than, and also perhaps not as rich as, the UML notation — especially concerning processes, or activities. In this paper, we view the UML and the OWL as being complementary to each other, and exploit their relative strengths. We provide a mapping between the two, through a set of mapping rules, which allow for the capture of UML activity diagrams in an OWL-ontology. This mapping, which results in a formalization of collaborative processes, also sets a basis for subsequent construction of executable models using the Colored Petri Nets (CPN) formalism. For this purpose, we also provide appropriate mappings from OWL-based ontological elements into CPN elements. A case study of a mortgage granting system is described, along with the potential benefits and limitations of our proposal.     

A parallel computing architecture for high-performance OWL reasoning

The Web Ontology Language (OWL) is a widely used knowledge representation language for describing knowledge in application domains by using classes, properties, and individuals. Ontology classification is an important and widely used service that computes a taxonomy of all classes occurring in an ontology. It can require significant amounts of runtime, but most OWL reasoners do not support any kind of parallel processing. We present a novel thread-level parallel architecture for ontology classification, which is ideally suited for shared-memory SMP servers, but does not rely on locking techniques and thus avoids possible race conditions. We evaluated our prototype implementation with a set of real-world ontologies. Our experiments demonstrate a very good scalability resulting in a speedup that is linear to the number of available cores.     

基于概念代数的本体演化

针对本体模型的维护和演化问题,将代数格与概念格相结合,定义概念代数,提出基于概念代数的奉体演化3层结构,包括原子概念层、原子概念关系层、应用层。分析概念代数与本体表示语言OWL之间的对应关系。在应用层中,利用概念代数根据应用的需要在原本体模型基础上构建面向应用的概念,并维护原有本体模型。实例证明了该方法的有效性。     

基于本体的公差规范的自动生成

针对目前公差规范依靠人工指定带来不确定性的问题,在基于本体的公差类型自动生成方法的基础上,研究基于本体的公差规范的自动生成。通过分析公差规范领域知识,提取其中涉及的概念和关系,以此构建公差规范本体,并采用Web本体语言（Web Ontology Language,OWL）编码实现该本体。在所实现本体的基础上,采用语义Web规则语言（Semantic Web Rule Language,SWRL）定义公差规范的生成规则,进而设计公差规范的自动生成算法。应用所设计算法,说明减速器中间传动轴的公差规范自动生成的过程。将为CAD系统中公差规范自动生成的研究提供有效的思路和方法。     

Extending the Unified Modeling Language for ontology development

There is rapidly growing momentum for web enabled agents that reason about and dynamically integrate the appropriate knowledge and services at run-time. The dynamic integration of knowledge and services depends on the existence of explicit declarative semantic models (ontologies). We have been building tools for ontology development based on the Unified Modeling Language (UML). This allows the many mature UML tools, models and expertise to be applied to knowledge representation systems, not only for visualizing complex ontologies but also for managing the ontology development process. UML has many features, such as profiles, global modularity and extension mechanisms that are not generally available in most ontology languages. However, ontology languages have some features that UML does not support. Our paper identifies the similarities and differences (with examples) between UML and the ontology languages RDF and DAML+OIL. To reconcile these differences, we propose a modification to the UML metamodel to address some of the most problematic differences. One of these is the ontological concept variously called a property, relation or predicate. This notion corresponds to the UML concepts of association and attribute. In ontology languages properties are first-class modeling elements, but UML associations and attributes are not first-class. Our proposal is backward-compatible with existing UML models while enhancing its viability for ontology modeling. While we have focused on RDF and DAML+OIL in our research and development activities, the same issues apply to many of the knowledge representation languages. This is especially the case for semantic network and concept graph approaches to knowledge representations. Initial sbmission: 16 February 2002 / Revised submission: 15 October 2002 Published online: 2 December 2002     

权限扩展RBAC模型的本体表示和实现

针对基于角色的访问控制(RBAC)模型对权限实体的刻画能力不足,提出了带权限层次扩展的RBAC模型。为结合本体在知识表示和推理方面的优势,提出了该模型的本体表示和实现方法。该方法使用Web本体语言(OWL)表示该扩展模型,借助语义Web规则语言(SWRL)定义模型中应用逻辑规则,隐式授权知识经规则推理获得。在此基础上,通过SPARQL协议和RDF查询语言(SPARQL)查询命令生成显式和隐式授权视图,实现系统安全状态分析。最后,给出了具体应用示例,表明该方法的可行性。     

Automatic extraction of OWL ontologies from UML class diagrams: a semantics-preserving approach

Full implementation of the Semantic Web requires widespread availability of OWL ontologies. Manual ontology development using current OWL editors remains a tedious and cumbersome task that requires significant understanding of the new ontology language and can easily result in a knowledge acquisition bottleneck. On the other hand, abundant domain knowledge has been specified by existing database schemata such as UML class diagrams. Thus developing an automatic tool for extracting OWL ontologies from existing UML class diagrams is helpful to Web ontology development. In this paper we propose an automatic, semantics-preserving approach for extracting OWL ontologies from existing UML class diagrams. This approach establishes a precise conceptual correspondence between UML and OWL through a semantics-preserving schema translation algorithm. The experiments with our implemented prototype tool, UML2OWL, show that the proposed approach is effective and a fully automatic ontology extraction is achievable. The proposed approach and tool will facilitate the development of Web ontologies and the realization of semantic interoperations between existing Web database applications and the Semantic Web.     

DAML+OIL: an ontology language for the Semantic Web

By all measures, the Web is enormous and growing at a staggering rate, which has made it increasingly difficult-and important-for both people and programs to have quick and accurate access to Web information and services. The Semantic Web offers a solution, capturing and exploiting the meaning of terms to transform the Web from a platform that focuses on presenting information, to a platform that focuses on understanding and reasoning with information. To support Semantic Web development, the US Defense Advanced Research Projects Agency launched the DARPA Agent Markup Language (DAML) initiative to fund research in languages, tools, infrastructure, and applications that make Web content more accessible and understandable. Although the US government funds DAML, several organizations-including US and European businesses and universities, and international consortia such as the World Wide Web Consortium-have contributed to work on issues related to DAML's development and deployment. We focus on DAML's current markup language, DAML+OIL, which is a proposed starting point for the W3C's Semantic Web Activity's Ontology Web Language (OWL). We introduce DAML+OIL syntax and usage through a set of examples, drawn from a wine knowledge base used to teach novices how to build ontologies.     

Reasoning of fuzzy relational databases with fuzzy ontologies

A significant interest developed regarding the problem of describing databases with expressive knowledge representation techniques in recent years, so that database reasoning may be handled intelligently. Therefore, it is possible and meaningful to investigate how to reason on fuzzy relational databases (FRDBs) with fuzzy ontologies. In this paper, we first propose a formal approach and an automated tool for constructing fuzzy ontologies from FRDBs, and then we study how to reason on FRDBs with constructed fuzzy ontologies. First, we give their respective formal definitions of FRDBs and fuzzy Web Ontology Language (OWL) ontologies. On the basis of this, we propose a formal approach that can directly transform an FRDB (including its schema and data information) into a fuzzy OWL ontology (consisting of the fuzzy ontology structure and instance). Furthermore, following the proposed approach, we implement a prototype construction tool called FRDB2FOnto. Finally, based on the constructed fuzzy OWL ontologies, we investigate how to reason on FRDBs (e.g., consistency, satisfiability, subsumption, and redundancy) through the reasoning mechanism of fuzzy OWL ontologies, so that the reasoning of FRDBs may be done automatically by means of the existing fuzzy ontology reasoner.© 2012 Wiley Periodicals, Inc.     

基于OWL的多媒体本体构建探索

文章首先分析了以XMLSchema语言为基础的MPEG-7标准在多媒体内容描述上存在的局限性和多媒体内容在计算机自动处理上的更多语义需求;然后结合MPEG-7标准,探索多媒体的OWL(OntologyWebLanguage)本体构建,具体包括低层次视频和音频描述符的OWL表示、高层次多媒体实体的OWL表示、多媒体片断分解的OWL表示。     

Integrity validation in semantic engineering design environment

A collaborative engineering design environment has been devised based on semantic Web technologies. The Semantic Engineering Design Environment (SEDE) consists of Engineering Ontology, Design Rules, Design Database, and Design Data Web Service. The Design Data Web Service provides users APIs (Application Programming Interface) so that distributed Design Participants interface each other. The domain knowledge of design objects can be logically expressed by OWL (Web Ontology Language). Design rules regarding change management are encoded in XQuery and stored as database triggers. Once design data changes, associated design rules will be validated by database systems. In this paper we introduce the overall architecture of the collaborative engineering design environment and present working scenarios with examples.