Web user interface adaptation by means of ontologies and rules

Abstract

The Web has evolved in recent years and became an integral part of everyday life. Many people have improved their quality of life, especially people with disabilities and old people. The evolution towards concepts such as Web accessibility is likely to bring about new opportunities, but, at the same time, new challenges for access to web-based products and services by people with disabilities, which can not be addressed through ad hoc assistive technology solutions. A possible solution is the exploration of the se- mantic knowledge about users and their context of use. These information items are not very usable if the semantic relationships of these information items with each other and with other meaningful information components are not established.<br />The investigation of semantic relationship between the entities in an information system, and their formal representation creates important new possibilities to automation purposes. We are able to explore and use this knowledge to derive the most suitable user interface characteristics according to each user and many other contributing factors. Thus, the information presentation could be adapted and could serve people with disabilities and older people much more efficiently than traditional technologies. In fact, our approach benefits also mobile device users and other individuals, since the needs and preferences that are essential to a user are a consequence of having a disability and/or it may be that the circumstances, devices, or other factors have led to a mismatch between them and the resources they wish to use.<br />To achieve the above mentioned goal, there is a need to appropriately model and interconnect the knowledge components related to the user interaction process, while also considering the user's profile and contextual information as essential components. The recently emerging Semantic Web Technology provides us with the tools and techniques to model and interconnect the heterogeneous information resources. The connection of multiple distributed ontologies using Distributed Description Logic, is applied to explore the domain of discourse.<br />Distributed Description Logics allow for inter-ontology subsumption, a notion that combines well with the vision of the Semantic Web.<br />Based on Answer Set Programming, we can encode our problem as a set of rules and the solution is found by the stable models or answer sets of these rules. The answer sets give us suggestions for relevant abstract user interface elements according to the used knowledge. Our proposed logical framework enables ontology-based interoperability and their integration using Answer Set Programming as an expressive nonmonotonic formalism.<br />The crucial element in our approach is the rule-based layer which generates abstract user interface elements. It is also exploitable for fulfilling more abstract scenar- ios in Web interfaces. A semantic mapping based on Distributed Description Logic, to connect the user's profile, impairment profile and contextual data is presented to show the validity of our approach.<br />The major contributions of this thesis are first, the development of OWL-DL ontologies in the context of enhancing Web interaction for all.<br />Second, the formally connected ontologies have been combined with a declarative nonmonotonic reasoning formalism like Answer Set programming and finally the generation of abstract user interface elements.<br />The future directions include the deployment of answer sets computed by the solver to gain a significant amount of details about users, which can be easily compared, analysed and used by the Interface Designer as well as by Data Transformation processes for further exploitation. The automatic population of the ontologies, and the automatic transformation of the answer sets could be helpful so that the information presentations are not chosen in advance, but could be available upon the prevalent information semantics during user interaction.