Jérôme Gensel

Modeling and Measuring Quality of Context Information in Pervasive Environments

Pervasive Environments offer new opportunities for users to dynamically access resources and services based on information characterizing their situation (context), generally assuming that this information is correct and trustworthy. In this scenario, the Quality of Context information (QoC) plays an important role for improving context-based adaptation processes and for ensuring the correct behavior of context-aware applications and services. Some research attempts have been done for modeling and measuring the quality of raw context information sensed from the environment. However, so far no attention has been paid to the quality evaluation of derived and inferred context information. This paper describes an approach for modeling and measuring quality of raw, inferred, and derived context information based on the following points of view: privacy, security, precision, completeness, and resolution. We propose a context management framework that support QoC in their various layers, protecting and providing QoC-enriched context information of users to context-aware applications and services.

A context-aware framework for health care governance decision-making systems: A model based on the Brazilian Digital TV

This paper proposes a governance decision-making framework for public health care systems. It encompasses and integrates data about family homes in a new intelligent health care information system. In order to support end-user interactions, the framework has been built on the GINGA middleware developed for the Brazilian Digital TV, whose full access will be country-wide in 2015. Based on five governance fields, namely knowledge, normative, clinical-epidemiological, administrative, and shared management, the framework relies on an Optical-WiMAX communication infrastructure (Brazilian Digital Belt), which will reach 82% of urban population in the Ceara State. In addition, we present a case study showing how the framework could be used for improving health care governance decisions.

Progressive Access to Knowledge in Web Information Systems through Zooms

In various application areas such as e-business, geographical information systems, education, etc., the Web is widely considered as a reliable approach to support information diffusion. If most of Web sites propose visually attractive and elaborated graphical web pages, requirements in Web-based Information Systems (WIS) are beyond visual design. The data managed and services proposed by WIS are characterized by a high level of complexity. WIS development is most of the time ‘ad hoc’ [1] which leads to more or less successful results. In [2], the authors describe as a “website crisis” the situation that results from no prior planning or analysis in web application development. WIS development methods and tools are needed so that IS on the web do not only consist of a collection of data with a rough web interface layered on top. Such methodological help and tools must take into account some adaptability to users, information presentation and navigation features.

Context-Aware Adaptation in Web-Based Groupware Systems

In this chapter, we propose a context-aware filtering process for adapting content delivered to mobile users by Web-based Groupware Systems. This process is based on context-aware profiles, expressing mobile users preferences for particular situations they encounter when using these systems. These profiles, which are shared between members of a given community, are exploited by the adaptation process in order to select and organize the delivered information into several levels of detail, based on a progressive access model. By defining these profiles, we propose a filtering process that considers both the user’s current context and the user’s preferences for this context. The context notion of context is represented by an object-oriented model we propose and which takes into account consideration both the user’s physical and collaborative context, including elements related to collaborative activities performed inside the groupware system. The filtering process selects, in a first step, the context-aware profiles that match the user’s current context, and then it filters the available content according to the selected profiles and uses the progressive access model to organize the selected information.

A Context-Based Awareness Mechanism for Mobile Cooperative Users

This paper presents a context-based awareness mechanism designed for users who access web-based collaborative systems using mobile devices. The limited capabilities of such devices (reduced display size, limited battery and memory capacity...) constitute intrinsic constraints which make even more tenuous the issue of delivering relevant information to collaborative mobile users. We propose here an object-based representation of the notion of context and an awareness mechanism which filters the available information according to both the physical (user’s location and device) and organizational (knowledge relative to the collaborative process) contexts of the user.

Semantic Analysis for the Geospatial Semantic Web

Semantic analysis is a new search paradigm for the Semantic Web, which aims the automatic extraction of semantic associations existing between individuals described in RDF(S) graphs. In order to infer additional semantic associations and to increase the accuracy of the analysis, we propose here, to adapt semantic analysis for OWL-DL ontologies.We also show that by taking into account spatio-temporal information which is usually attached to resources, new and possibly interesting semantic associations can be discovered. Moreover, we propose to handle spatial and temporal contexts in order to limit the scope of the analysis to a given region of space and a given period of time, considered interesting from the user’s point of view. For reasoning with spatial and temporal information and relations we use ONTOAST, a spatio-temporal representation and querying system, which is compatible with OWL-DL.

An Object Approach for Web Presentations

In the last decade, multimedia and, more particularly, video systems have benefited from a tremendous research interest. The main reason for this is the increasing ability computers now have for supporting video data, notably thanks to unceasing improvements in data compression formats (as MPEG-2 and MPEG-4), in network transfer rates and operating systems [1], and in disk storage capacity. Unsurprisingly, new applications have risen such as video on demand, video conferencing and home video editing which directly benefit from this evolution. Following this trend, research efforts ([2], [3]) have been made to extend DataBase Management Systems (DBMS) so that they support video data types not simply through Binary Large Objects (BLOB). Indeed, DBMS seem to be well-suited systems for tackling problems posed by the video, namely storage, modeling, querying and presentation. Video data types must be physically managed apart from other conventional data types in order to fulfill their performance requirements. Video modeling must take into account the hierarchical structure of a video (shots, scenes and sequences) and allow overlapping and disjoint segment clustering [4]. The video query language must (accordingly to MPEG-7 descriptions [5]) allow one to query video content using textual annotations or computed signatures (colour, shape, texture…) and deal with the dynamic (movements) of objects in the scenes as well as with semi-structural aspects of videos and, finally, must offer the possibility of creating new videos.