SpaceSemantics: an architecture for modeling environments

The notion of modeling location is fundamental to location awareness in ubiquitous computing environments. The investigation of models and the integration with the myriad of location sensing technologies makes for a challenging discipline. Despite notable development of location models, we believe that many challenges remain unresolved. Complexity and scalability, diverse environments coupled with various sensors and managing the privacy and security of sensitive information are open issues. In this paper we discuss our previous experience combining location sensing with mobile agents and how the lessons learnt have lead to the conception of SpaceSemantics, an open architecture for modeling environments

Working Document on Gloss Ontology

This document describes the Gloss Ontology. The ontology and associated class model are organised into several packages. Section 2 describes each package in detail, while Section 3 contains a summary of the whole ontology

A flexible location-context representation

Ubiquitous computing and the development of context-aware applications have been limited by the lack of open and generic solutions. In this paper we propose a flexible location-context representation which supports data acquired through multiple sensors represented in different space models.Fundação para a Ciência e a Tecnologia (FCT) - (SFRH/BD/8279/2002)

Interrogation des données spatio-temporelles de géolocalisation indoor à partir des trajectoires hybrides

Le GPS (Global Positioning System) basé sur la visibilité directe entre le satellite et le récepteur, s’est imposé pour la localisation outdoor. En l’absence de signal GPS, la localisation d’une cible dans les environnements indoor peut se faire avec un réseau de capteurs. Ces réseaux déployés dans les bâtiments sont de plus en plus nombreux et servent à plusieurs applications basées sur la localisation : surveillance, détection, navigation, etc. Ces capteurs de localisation indoor génèrent une quantité importante d’informations de tracking. Le contexte d’application de ce travail est celui des systèmes de localisation indoor basés sur les cellules Wifi, sur les capteurs ICCARD et sur les caméras de vidéosurveillance. Dans un tel contexte, il n’existe aucun système global de référence similaire au GPS : les informations de localisation sont hétérogènes (positions géométriques et symboliques / multitude de systèmes de référence). Cet article présente un ensemble de démarches qui ont permis de concevoir et implémenter un framework utilisant les informations générées par les réseaux de capteurs de localisation déployés dans un environnement indoor, illustré dans le cadre du forensic

A Novel Hybrid Authentication Model for Geo Location Oriented Routing in Dynamic Wireless Mesh Networks

Authentication is an essential part of any network and plays a pivotal role in ensuring the security of a network by preventing unauthorised devices/users access to the network. As dynamic wireless mesh networks are evolving and being accepted in various fields, there is a strong need to improve the security of the network. It’s features like self-organizing and self-healing make it great but get undermined when rigid authentication schemes are used. We propose a hybrid authentication scheme for such dynamic mesh networks under three specified scenarios; full authentication, quick authentication and new node authentication. The proposed schemes are applied on our previous works on dynamic mesh routing protocol, Geo location Oriented Routing Protocol (GLOR Simulation results show our proposed scheme is efficient in terms of resource utilization as well as defending against security threats

Video spatio-temporal filtering based on cameras and target objects trajectories - Videosurveillance forensic framework

International audienceThis paper presents our work about assisting video-surveillance agents in the search for particular video scenes of interest in transit network. This work has been developed based on requirements defined within different projects with the French National Police in a forensic goal. The video-surveillance agent inputs a query in the form of a hybrid trajectory (date, time, locations expressed with regards to different reference systems) and potentially some visual descriptions of the scene. The query processing starts with the interpretation of the hybrid trajectory and continues with a selection of a set of cameras likely to have filmed the spatial trajectory. The main contributions of this paper are: (1) a definition of the hybrid trajectory query concept, trajectory that is constituted of geometrical and symbolic segments represented with regards to different reference systems (e.g., Geodesic system, road network), (2) a spatio-temporal filtering framework based on a spatio-temporal modeling of the transit network and associated cameras

Evaluation of a Location Linked Notes System

We present a location-aware messaging system that lets users read and post notes tied to a particular location. We developed multiple clients (desktop, PDA and cell phone) so that users could choose the most contextually-appropriate device to interact with the system. We allowed remote access and authoring to avoid imposing artificial restrictions on users. We report on our initial evaluation of the system. The goal of the evaluation was to explore novel potential uses of the system and to identify users' preferences regarding the different system features. In our evaluation, we found that users were receptive of this system for leaving and receiving location-targeted reminders. They also overwhelmingly approved of the remote access and authoring capability, and suggested scenarios where these features would be crucial. We discuss our experiences building the system and our findings from the initial evaluation

Providing other people's trails for navigation assistance in physical environments

Asking other people the way has always been a widespread social wayfinding technique. In recent years wayfinding in unknown spatial environments has increasingly been supported by electronic navigation assistants. However, the social aspects of wayfinding, such as using other peoples’ experiences, have widely been ignored in the context of electronic navigation systems. In electronic environments such as the WWW the availability of community knowledge - also driven by Web 2.0 paradigms - becomes more and more valuable to users. Other people’s experiences, including recorded browsing paths and activities - so called user trails - are used for recommendation and navigation support and allow users to navigate vast information spaces more easily. In this paper we propose an approach for trail-based navigation in physical environments. An analysis and comparison of the concept of trails in both application areas establishes the basis for a trail model and the implementation of a trail-based navigation system prototype for mobile phones. Practical experiences with a prototype application and potential applications of trail-based navigation assistants are discussed in the context of a tourist scenario in the old town of Salzburg