Feature Weighting is one of the most difficult tasks when developing Case Based Reasoning applications. This complexity grows when dealing with ill-defined wide domains with a sparse case base. Moreover, most widely-used feature selection and feature weighting methods assume that features are either relevant in the whole instance space or irrelevant through-out. However, it is often the case th...

User location service for context-aware applications in wireless network is of great academia and industry interest, many research efforts were spent on obtaining location information within wireless network. This paper presents a different approach of determining location information. The location information is obtained over an ad-hoc wireless network, using IEEE 802.11 protocol. A triangulat...

This paper discusses inference strategies of context-free bi-grammars for example based machine translation (EBMT). The EBMT system EDGAR is discussed in detail. The notion of invertible context-free feature bi-grammar is introduced in order to provide a means to decide upon the degree of ambiguity of the inferred bi-grammar. It is claimed that a maximally invertible bi-grammar can enhance the ...

A high adaptable middleware has been an essential platform to provide more flexible services for multimedia, mobile, and ubiquitous applications in ubiquitous computing environments. In addition, the persistent services of these application systems and their middleware in ubiquitous computing are required so that they can be aware of the frequent and unpredictable changes in users’ requirements...

Location and other spatio-temporal attributes are important in mobile and context aware computing. We propose a new model for location and new abstractions in support of location and context awareness. We present a unified model of raw location, and introduce the concepts of spatial realms and spatial states, which support higher level concepts of location. We show how key application requireme...

Intelligent agents have to be able to merge (possibly conflicting) pieces of information obtained from different sources to produce a coherent picture of the world. In this paper we propose a multi-agent model of context-sensitive merging. We show that the success of the model depends, to a large extent, on the availability of suitable merging operations on epistemic states. As a result, we inv...

This paper presents an agent-based system for building and operating agent-based context-aware services in public spaces, including museums. The system provides users with agents and detects the locations of users and deploys location-aware user-assistant agents at computers near the their current locations by using active RFID-tags. When a visitor moves between exhibits in a museum, this dynam...

Location-based context-aware services for mobile users need to collaborate in disparate networks. Services come and go as the user moves and no central repository is available. The user’s personal information and service usage statistics need to be protected. To support service collaboration we propose a service infrastructure that relies on an event-based serviceoriented architecture. We imple...

New sensing technologies, as RFID readers, are being incorporated into mobile devices to provide users with new interaction experiences. And, the combinations of these new technologies open up new challenging application scenarios. One of the areas that could exploit this potential is the design of interactive solutions for context-aware applications applied to learning environments. This artic...

In recent years there has been a growing interest in developing Ambient Intelligence based systems in order to create smart environments for user and environmental monitoring. In fact, higher-level monitoring systems with vital information about the user and the environment around him/her represents an improvement of the quality of care provided. In this paper, we propose an architecture that i...