Wided Oueslati

MAVIE: A mobile agents view synchronization system

Data warehouse view definitions are constructed thanks to information sources schemas. When these latter evolve, view definitions may become undefined. In this paper, we propose a system based on mobile agents destined to achieve view definitions repairing or synchronization following schema changes happened at distributed, heterogeneous and autonomous information sources. The proposed solution decreases the synchronization time thanks to parallelism permitted by agents, avoids network saturation by enhancing local processing and increase local intelligence.

Detection of Opinion Leaders in Social Networks: A Survey

With the development of new media such as social networking sites, content sharing sites, blogs and micro blogs a profound transformation in terms of communication between consumers and companies has been created. In fact, this great revolution of the web has allowed different users to interact, express their opinion on a product or a service and post comments. Then, internet users have gone from passive to active actors who are able to produce information and make data available on the web as a rich opinions source. Therefore companies must deal with this reality, to know what others may say about their products of competing brands because the only and the best way to sell their products in good condition is to produce what consumers want. Along with this phenomenon, recent years have seen the birth of a generation of Internet users elected by the company to help it to manage its on-line reputation. Those users are called opinion leaders or influencers; they have a high capacity to influence those around them because they are considered to be more experienced, objective and able of provoking the emotions of someone else. Therefore the necessity of identifying opinion leaders has been proved more and more crucial. The goal of this paper is to present different research works that aimed to detect opinions leaders in social network.

A Mobile Agent view Synchronization System to Uphold a Trajectory data Warehouse

Abstract The trajectory data warehouse (TDW) view definitions are constructed from heterogeneous mobile information sources schema that are more and more independent. In fact, they frequently change their content due to perpetual transactions (data changes) and may change their structure due to continual users’ requirements evolving. Managing appropriately the view definition synchronization is a necessity since, the TDW is considered as the core component of the modern decision support systems. The aim of this paper is to propose a mobile agent view synchronization system to uphold a trajectory data warehouse under schema changes.

An Immersive System for 3D Floods Visualization and Analysis

Climate change has serious implications on our environment. Examples of such natural risks are massive rainfalls and the rise of ocean levels. Millions of people are exposed to the risk of extreme floods and storms. It is therefore crucial to develop analytical tools that allow us to evaluate the threats of floods and to investigate the influence of mitigation and adaptation measures, such as stronger dikes, adaptive spatial planning, and flood disaster plans. The objective of our work is to present a flood management system that aims to model and visualize floods. It provides realistic images to help users in understanding and interpreting these disaster scenarios. In order to investigate the applicability in practice, we illustrated the use of our system for real-world data in a case study for the city of Paris, France.

Maintaining a Trajectory Data Warehouse Under Schema Changes with the Mobile Agent View Adaptation Technique

With the development of pervasive systems and positioning technology, the analysis of data resulting from moving objects trajectories has attracted a particular interest. Those data are called trajectory data and are stored in a suitable repository called trajectory data warehouse (TDW). TDW view definitions are constructed from heterogeneous mobile information sources schema. Those latter are more and more autonomous and they often evolve by changing their contents and/or their schema then the TDW view definition may become undefined and consequently the analysis process may be affected. For this reason, it is important to achieve view definitions restoring or synchronization following schema changes occurred at the heterogeneous mobile information sources. The goal of this paper is to propose a TDW view definition maintenance based on mobile agent view adaptation system.

A framework for the trajectory data warehouse conceptual modeling support: a mobile hospital trajectory case study

Thanks to the new positioning and information capture technologies; trajectory data which handle information related to moving objects can be captured and treated. This gave birth to a new data warehouse type called trajectory data warehouse that is essential to model and to implement to analyze and understand the nature and the behavior of movements of objects in various contexts. However, it is still difficult to find references models, since classical conceptual modeling does not incorporate the specificity of trajectory data due to the complexity of their components that are spatial, temporal and thematic (semantic). Motivated by this luck, we propose in this paper a new modeling framework based on an UML profile to support the conceptual modeling or design of data resulting from moving objects.

Extending UML for trajectory data warehouses conceptual modelling

The new positioning and information capture technologies are able to treat data related to moving objects taking place in targeted phenomena. This gave birth to a new data source type called trajectory data (TD) which handle information related to moving objects. Trajectory Data must be integrated in a new data warehouse type called trajectory data warehouse (TDW) that is essential to model and to implement in order to analyze and understand the nature and the behavior of movements of objects in various contexts. However, classical conceptual modeling does not incorporate the specificity of trajectory data due to the complexity of their components that are spatial, temporal and thematic (semantic). For this reason, we focus in this paper on presenting the conceptual modeling of the trajectory data warehouse by defining a new profile using the StarUML extensibility mechanism. Keywords—Trajectory data; trajectory data warehouse; UML extension; trajectory UML profile.

Facial nerve stream modeling for facial paralysis patients states evolution

The objective of this work is to supervise the states evolution of patients affected by facial paralysis leading to recovery. Modeling facial nerve stream trajectory data seems to be an essential step leading to perform our purpose. In fact, it permits representation unification and facilitates data querying in order to ensure recovery surveillance and the disease understanding. Moreover a visualization algorithm is proposed to track facial nerve stream in order to observe recovery progress and to identify the occurrence of conduction problem preventing it.

Pre-learning from mobile professionals' Trajectory

With the advent of pervasive systems and positioning technologies, a huge trajectory data related to moving objects is generated but not efficiently exploited by decision makers. Trajectory data warehouse seems to be a right repository for this kind of data. The aim of this work is to design a Trajectory data warehouse to gather trajectory data collected partially by mobile professionals for analysis and decision purpose.