IRIT Laboratory

Toulouse, France

IRIT Laboratory

Toulouse, France
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Amroune M.,University of Tébessa | Zarour N.,University of Mentouri Constantine | Charrel P.J.,University of Toulouse II – Le Mirail | Inglebert J.M.,IRIT Laboratory
Proceedings of the 2012 IEEE 2nd International Workshop on Advanced Information Systems for Enterprises, IWAISE 2012 | Year: 2012

In systems engineering, reuse is defined as the utilization of previously developed systems engineering products or artifacts such as architectures and requirements. Previously, we proposed an approach named AspeCiS to develop a Cooperative IS (CIS) from existing ISs by using their artifacts such as requirements, and design. This approach can be justified by the fact that it is frequently not easy for a sole Information System (IS) to achieve a new emerging complex task. One solution is to make existing ISs collaborate to realize this task. So, AspeCiS is structured in three phases, which are: (i) discovery and analysis of Cooperative Requirements, (ii) development of Cooperative Requirements models, and (iii) preparation of the implementation phase. The main issue of AspeCIS is the definition of Cooperative Requirements using the Existing and Additional Requirements, which should be composed with the Aspectual Requirements. We earlier studied how to elicit the Cooperative Requirements in AspeCiS. In the present work, we propose to combine Model-driven engineering (MDE) approach with the Aspect paradigm to define Cooperative Requirements Models. For this, we propose an UML profile which allows designer to model AspeCiS's aspects to produce cooperative requirements models. This profile is a response to the following question: How to model Aspects in AspeCiS? © 2012 IEEE.

Djabri M.R.,University of Tébessa | Amroune M.,University of Tébessa | Amroune M.,LIRE Laboratory | Amroune M.,IRIT Laboratory
2012 International Conference on Information Technology and e-Services, ICITeS 2012 | Year: 2012

The success of any new software development paradigm heavily relies on providing solid support of tools, methods, and languages. Over the last few years, the aspect oriented paradigm has matured and gained widespread industrial support at the programming phase, while aspect oriented modeling (AOM) is still a fertile field of research. Due to its substantial and crucial importance, the application of aspect orientation at the design stage in software development process has interested many researchers. Recently, numerous works have attempted to provide aspect oriented support at the model level, in various forms that many of which were based on UML, however, there exists no generic AOM language that is capable of supporting all the concepts introduced by the different aspect oriented languages, such as AspectC++. Due to the substantial importance, and to the large use of AspectC++ at the programming level, in software development process, we propose, in this paper, a UML profile for AspectC++ language, which aim to provide AspectC++ specific modeling facility, allowing the modelers to produce aspect oriented models which conform to this language. © 2012 IEEE.

Escrig B.,IRIT Laboratory | Fares F.,IRIT Laboratory | Boucheret M.-L.,IRIT Laboratory | Calmettes T.,Thales Alenia | Guillon H.,French National Center for Space Studies
International Journal of Satellite Communications and Networking | Year: 2015

In this paper, we evaluate several multiuser detection (MUD) architectures for the reception of asynchronous beacon signals in the ARGOS satellite system. The case of synchronous signals is studied first. Though impractical, this case provides useful guidance on the second part of the study, that is, the design of MUD receivers for asynchronous users. This paper focuses more particularly on successive interference cancellation (SIC) receivers because they have been shown to achieve a good performance complexity trade-off. Several Eb/N0 degradation curves are obtained as a function of channel parameters. With these curves, a performance analysis is presented in order to determine in which conditions it is possible to successfully decode none, one, or more beacon signals. We show that SIC receivers can improve the percentage of served beacons from 50% to more than 67% for a population of 37,600 beacons. Copyright © 2014 John Wiley & Sons, Ltd.

Ali-Yahiya T.,University Pierre and Marie Curie | Beylot A.-L.,IRIT Laboratory | Pujolle G.,University Pierre and Marie Curie
Telecommunication Systems | Year: 2010

This article addresses downlink resource allocation strategies in Mobile WiMAX based on IEEE802.16e standard, using Orthogonal Frequency Division Access (OFDMA). We consider Mobile WiMAX resource allocation strategies for allocating higher layer data to the basic resource allocation units (slots) of OFDMA frames. Then, we introduce two simple allocation methods: Adaptive Slot Allocation (ASA) and Reservation-Based Slot Allocation (RSA). Both approaches consider a fair resource allocation among different types of service flows (SFs) by considering their QoS characteristics and their channel qualities. The ultimate objective of the proposed approaches is to maximize the capacity of the system subject to the quality of service (QoS) constraints for each type of (SFs) in terms of data rate and Bit Error Rate (BER). © 2009 Springer Science+Business Media, LLC.

Moulahi B.,IRIT Laboratory | Tamine L.,IRIT Laboratory | Ben Yahia S.,LIPAH
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

A large body of work in the information retrieval area has highlighted that relevance is a complex and a challenging concept. The underlying complexity appears mainly from the fact that relevance is estimated by considering multiple dimensions and that most of them are subjective since they are user-dependent. While the most used dimension is topicality, recent works risen particularly from personalized information retrieval have shown that personal preferences and contextual factors such as interests, location and task peculiarities have to be jointly considered in order to enhance the computation of document relevance. To answer this challenge, the commonly used approaches are based on linear combination schemes that rely basically on the non-realistic independency property of the relevance dimensions. In this paper, we propose a novel fuzzy-based document relevance aggregation operator able to capture the user’s importance of relevance dimensions as well as information about their interaction. Our approach is empirically evaluated and relies on the standard TREC1 contextual suggestion dataset involving 635 users and 50 contexts. The results highlight that accounting jointly for individual differences toward relevance dimension importance as well as their interaction introduces a significant improvement in the retrieval performance. © Springer International Publishing Switzerland 2014.

Escrig B.,IRIT Laboratory
IEEE Transactions on Wireless Communications | Year: 2011

\boldmath We design a cooperative protocol in the context of wireless mesh networks in order to increase the reliability of wireless links. Destination terminals ask for cooperation when they fail in decoding data frames transmitted by source terminals. In that case, each destination terminal D calls a specific relay terminal B with a signaling frame to help its transmission with source terminal S. To select appropriate relays, destination terminals maintain tables of relay terminals, one for each possible source address. These tables are constituted by passively overhearing ongoing transmissions. Hence, when cooperation is needed between S and D, and when a relay B is found by terminal D in the relay table associated with terminal S, the destination terminal sends a negative acknowledgment frame that contains the address of B. When the best relay B has successfully decoded the source message, it sends a copy of the data frame to D using a selective decode-and-forward transmission scheme. The on-demand approach allows maximization of the spatial multiplexing gain and the cooperation of the best relay allows maximization of the spatial diversity order. Hence, the proposed protocol achieves optimal diversity-multiplexing trade-off performance. Moreover, this performance is achieved through a collision-free selection process. © 2011 IEEE.

Soulier L.,IRIT Laboratory | Tamine L.,IRIT Laboratory | Bahsoun W.,IRIT Laboratory
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

This paper presents a novel collaborative document ranking model which aims at solving a complex information retrieval task involving a multi-faceted information need. For this purpose, we consider a group of users, viewed as experts, who collaborate by addressing the different query facets. We propose a two-step algorithm based on a relevance feedback process which first performs a document scoring towards each expert and then allocates documents to the most suitable experts using the Expectation-Maximisation learning-method. The performance improvement is demonstrated through experiments using TREC interactive benchmark. © 2013 Springer-Verlag.

Musat C.-C.,Ecole Polytechnique Federale de Lausanne | Faltings B.,Ecole Polytechnique Federale de Lausanne | Roussille P.,IRIT Laboratory
Proceedings - SocialCom/PASSAT/BigData/EconCom/BioMedCom 2013 | Year: 2013

In this paper we investigate the impact of antagonism in online discussions. We define antagonism as a new class of textual opinions - direct sentiment towards the authors of previous comments. We detect the negative sentiment using aspect-based opinion mining techniques. We create a model of human behavior in online communities, based on the network topology and on the communication content. The model contains seven hypotheses, which validate two intuitions. The first intuition is that the content of the messages exchanged in an online community can separate good and insightful contributions from the rest. The second intuition is that there is a delay until the network stabilizes and until standard measures, such as betweenness centrality, can be used accurately. Taken together, these intuitions are a solid case for using the content of the communication along with network measures. We show that the sentiment within the messages, especially antagonism, can significantly alter the community perception. We use real world data, taken from the Slashdot 1 discussion forum to validate our model. All the findings are accompanied by extremely significant t-test p-values. © 2013 IEEE.

El Hamlaoui M.,IRIT Laboratory | El Hamlaoui M.,Mohammed V University | Trojahn C.,IRIT Laboratory | Ebersold S.,IRIT Laboratory | Coulette B.,IRIT Laboratory
CEUR Workshop Proceedings | Year: 2014

The overall goal of our approach is to relate models - of a given domain - that are designed by different actors in different Domain Specific Languages, and thus are heterogeneous. Instead of building a single global model, we propose to organize the different source models as a network of models, which provides a global view of the system through a correspondence model. This latter, conform to a correspondence meta-model is built via a manual matching process. In this paper we explore the possibility of representing models as ontologies and take advantage of an automated process to match order to enhance the automation of the matching process.

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