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ontologies for Knowledge modeling in construction planning • vito getuli
In this regard, there are several implications. For example, a system-application may already use another ontology, developed in a language other than that which the developers have chosen for building a new ontology. Many studies demonstrate that merging different ontologies, developed by using different ontological languages can require a lot of effort - two languages coming from different branches of the ontology-language research communities may not be compatible, and may require a strong manual adaptation in order to provide a satisfying interoperability. However, developers may be constrained by the fact that development tools may support only a few languages. The situation is even worse for new applications where for design considerations is chosen a more appropriate language different from the one used by previous applications which though need to be consulted as well. On the other hand, an appropriate ontology representation language may facilitate the integration of an ontology into a new application. Moreover, a newer ontological representation language may just be more expressive than the other languages of choice, and translators to and from those other languages may already exist as well. We should note that the ontology community has already developed a number of such translators, although many of them suffer from partial loss of knowledge in the translation process. 1.3 Ontology development environments Building ontologies is a complex and time-consuming activity, especially when developers have to implement them in an ontological language, without any supports in terms of software applications. To ease this activity, in the mid-1990s the first ontology building environments were created. They provided an interface to support developers in the main activities of the ontology development process, such as conceptualization, implementation, consistency checking, and documentation. In the last few years, a number of ontology tools have been created with different purposes. In (Gomez-Pèrez 2002) a list of the main groups of those tools distinguished by function is presented: • Ontology development tools. This group includes tools and integrated suites that can be used to build a new ontology from scratch. In addition to the common editing and browsing functions, these tools usually support ontology documentation, ontology export and import to/from different formats and ontology languages, ontology graphical editing, ontology library management, etc. • Ontology evaluation tools. They are used to evaluate the content of ontologies and their related technologies. Ontology content evaluation addresses the issues related to the
