螃哈哈一只

这里是Protege教程中一些比较重要的片段，完整教程在http://www.crabone.com/index.php/protege-introduction#more-6

当我们再次回顾创建类的6种方法时，我们可曾反过来想想，如果让我们来设计OWL语言，我们会设计出几类创建类的方法？

我们会发现，上面的这些类的定义方法， 阅读全文 »

其实就是一个属性的类型和范围，比如 int i；3<i<10 那么int就是i的domain，range就是3-10。

用英文来形象的表达就是：Properties link individuals from the domain to individuals from the range.

在我们这个Organization的例子中，我们拿hasInterest这个Property来说，它的domain就是Organization，它的Range就是Interest。

注意！Properties的domain，range和Properties的6大特性不一样，6大特性那是一种推理机制要用到的约束——Constraint，而domain，range是一种公理——axiom。什么意思？约束是用来限制的，可以用推理机制来验证，如果限制出了问题就会推理出错。而公理总是对的，推理要基于它们来推理。举个例子，hasTopping的domain我们定义为Pizza，如果在本体上，发现hasTopping连接到了icecream，那么是不会报错的，OWL会认为，icecream为Pizza的子类，这在W3C的文档上有详细的语义推理定义，见下面的公式。除非……你在构建本体的时候强行定义了，icecream和Pizza是相互Disjoint的，见3.5节。

这里是Protege教程中一些比较重要的片段，完整教程在http://www.crabone.com/index.php/protege-introduction#more-6

OWL Properties代表了一种关系 relationship，在OWL里，有2种类型的Properties。一种叫Object Properties，代表了individual到individual之间的一种关系。还有一种叫Datatype Properties，代表了individual和基本数据类型的关系，有点像类的属性，比如年龄、身高等。还有一种叫Annotation properties，是属于元数据，数据的数据，可以用来解释Classes、Individual、Object/Datatype Properties。下图以这3种类型，举个例子：

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这里是Protege教程中一些比较重要的片段，完整教程在http://www.crabone.com/index.php/protege-introduction#more-6

DisjointClasses、SubClassOf、EquivalentClasses是类的三大公理，见下图：

SubClassOf已经在上一节讲过了， 阅读全文 »

这里是Protege教程中一些比较重要的片段，完整教程在http://www.crabone.com/index.php/protege-introduction#more-6

创建类，有6种方式，在我的OWL入门教程中，有非常详细的阐述，想了解的朋友去看看。
6种创建类的方法
在创建本体的时候，用的最多的当然是第一种方法————Named Class。这种Class也被称为Plain Class，意思就是没有任何语义的类，仅仅是一个标示。好了，我们开始！

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URL

http://pellet.owldl.com/ontology-browser/

是一个用OWL API+EXT做的简便本体浏览器，可以关注下

用Protege做本体开发，一定要搞清楚Protege的版本，这点很重要。

初学者常犯的错误就是用protege-owl API来编辑4.0的OWL2.0文件，OWL2.0要用OWL API来编辑。

The NeOn project is investigating the entire life cycle of networked ontologies that enable complex, semantic applications. As the amount of semantic information available online grows, semantic applications are becoming increasingly ubiquitous, Web-centric and complex. The NeOn Toolkit and the NeOn methodology lie at the core of the NeOn vision, defining the standard reference infrastructure and the standard development process for creating and maintaining large-scale semantic applications. The first version of the NeOn Toolkit for ontology engineering has just been released in open source by the Neon Consortium.

NeOn is a 14.7 million euro project involving fourteen European partners. It started in March 2006 and will have a duration of four years. NeOn addresses the complete R&D cycle of the emerging generation of semantically enriched applications, which exist and operate in an open environment of highly contextualized, evolving and networked ontologies. It aims to achieve and facilitate the move from feasibility in principle, to concrete cost-effective solutions that can support the design, development and maintenance of large-scale, semantic-based applications. In particular, the project is investigating methods and tools for managing the evolution of networked ontologies, for supporting the collaborative development of ontologies, and for the contextual adaptation of semantic resources.

NeOn has developed an open service-centred reference architecture for managing the complete life cycle of networked ontologies and metadata. This architecture is realized through the NeOn Toolkit and complemented by the NeOn methodology for system development using networked ontologies.

NeOn Toolkit Launched
The NeOn Toolkit provides a next-generation ontology engineering environment for semantic applications. It is designed around an open and modular architecture, which includes infrastructure services such as registry and repository, and supports distributed components for ontology management, reasoning and collaboration in networked ontologies. Building on the Eclipse platform, the Toolkit provides an open framework for plug-in developers. The NeOn Toolkit is freely available in open source as the reference implementation of the NeOn architecture. The first open-source release of the Toolkit was just recently launched at the latest NeOn Glowfest at ISWC07 – the International Semantic Web Conference – in Busan, Korea on the 13th November. NeOn Glowfest is a series of seminars and discussions intended to gather together the members – both users and developers – of the NeOn community.

RACER stands for Renamed ABox and Concept Expression Reasoner.
RacerPro is the commercial name of the software.

The origins of RacerPro are within the area of description logics. Since description logics provide the foundation of international approaches to standardize ontology languages in the context of the so-called semantic web, RacerPro can also be used as a system for managing semantic web ontologies based on OWL (e.g., it can be used as a reasoning engine for ontology editors such as Protégé). Futhermore, RacerPro can also be seen as a semantic web information repository with optimized retrieval engine because it can handle large sets of data descriptions (e.g., defined using RDF). Last but not least, the system can also be used for modal logics such as Km.

有了第四章的基础，我们来写一个自己的Model 阅读全文 »