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3,426 results on '"Université Toulouse 1 Capitole - UT1 (FRANCE)"'

1. Identification and Assessment of Obsolescence in the Early Stages of System Design

Author

Marc Zolghadri, Sophia Salas Cordero, Claude Baron, Rob A. Vingerhoeds, Laboratoire QUARTZ (QUARTZ ), Université Paris 8 Vincennes-Saint-Denis (UP8)-Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-ISAE-Supméca Institut Supérieur de Mécanique de Paris (ISAE-Supméca), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), ISAE-Supméca Institut Supérieur de Mécanique de Paris (ISAE-Supméca), Équipe Ingénierie Système et Intégration (LAAS-ISI), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and ISAE-Supméca – Institut supérieur de mécanique de Paris (FRANCE)

Subjects
Obsolescence criticality index, Identification, ComputingMilieux_THECOMPUTINGPROFESSION, Computer science, General Engineering, Assessment, Systems engineering, House of obsolescence, [SPI]Engineering Sciences [physics], Identification (information), Autre, Obsolescence, Obsolescence management process, Systems design
Abstract

International audience; Obsolescence is the fact that an entity (physical or logical) is becoming outdated or no longer possesses the required level of performance. The objectives of this article are twofold. First, it is intended to contribute to the understanding of obsolescence propagation. Secondly, two supporting approaches for the Identification and Assessment phases are proposed: the House of Obsolescence and the System Obsolescence Criticality Analysis. The former allows the mapping of obsolescence propagation via dependencies, whether imposed changes are desired or imposed, by external actors to the system architecture. Whereas, the objective of the latter is to assign an obsolescence criticality index to the identified risks in order to prioritize them for solution or mitigation determination during the analysis phase. The tools make extensive use of the modeled system knowledge through the application of Systems Engineering. The application of these approaches is presented through an illustrative study.

Published
2022

2. Satellite Image Compression and Denoising With Neural Networks

Author

Vinicius Alves de Oliveira, Marie Chabert, Thomas Oberlin, Charly Poulliat, Mickael Bruno, Christophe Latry, Mikael Carlavan, Simon Henrot, Frederic Falzon, Roberto Camarero, Centre National d'Études Spatiales - CNES (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Thales (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), ESA - ESTEC (NETHERLANDS), Artificial and Natural Intelligence Toulouse Institute - ANITI (FRANCE), Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (FRANCE), and Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (Toulouse, France)

Subjects
Image compression, Image denoising, Neurosciences, Electrical and Electronic Engineering, Geotechnical Engineering and Engineering Geology, Neural networks
Abstract

Earth observation through satellite images is crucial to help economic activities as well as to monitor the impact of human activities on ecosystems. Current satellite systems are subjected to strong computational complexity constraints. Thus, image compression is perfomed onboard with specifically tailored algorithms while image denoising is performed on the ground. In this letter, we intend to address satellite image compression and denoising with neural networks. The first proposed approach uses a single neural architecture for joint onboard compression and denoising. The second proposed approach sequentially uses a first neural architecture for onboard compression and a second one for on ground denoising. For both approaches, the onboard architectures are lightened as much as possible, following the procedure proposed in [1]. The two approaches are shown to outperform the current satellite imaging system and their respective pros and cons are discussed.

Published
2022

3. A marginalised particle filter with variational inference for non‐linear state‐space models with Gaussian mixture noise

Author

Xiaodong Lu, Cheng Cheng, Jean-Yves Tourneret, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Northwestern Polytechnical University (CHINA), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France)

Subjects
Non‐Gaussian noise, Computer science, Gaussian, Posterior probability, non‐linear state‐space models, State vector, Context (language use), Non‐linear state‐space models, TK5101-6720, Bayesian inference, Gaussian mixture noise, Noise, symbols.namesake, marginalised particle filter, Marginalised particle filter, Telecommunication, symbols, Traitement du signal et de l'image, State space, Applied mathematics, Electrical and Electronic Engineering, Variational inference, Particle filter, non‐Gaussian noise, variational inference
Abstract

This work proposes a marginalised particle filter with variational inference for non‐linear state‐space models (SSMs) with Gaussian mixture noise. A latent variable indicating the component of the Gaussian mixture considered at each time instant is introduced to specify the measurement mode of the SSM. The resulting joint posterior distribution of the state vector, the mode variable and the parameters of the Gaussian mixture noise is marginalised with respect to the noise variables. The marginalised posterior distribution of the state and mode is then approximated by using an appropriate marginalised particle filter. The noise parameters conditionally on each particle system of the state and mode variable are finally updated by using variational Bayesian inference. A simulation study is conducted to compare the proposed method with state‐of‐the‐art approaches in the context of positioning in urban canyons using global navigation satellite systems.

Published
2021

4. Formal Monotony Analysis of Neural Networks with Mixed Inputs: An asset for certification

Author

Guillaume Vidot, Mélanie Ducoffe, Christophe Gabreau, Ileana Ober, Iulian Ober, Airbus (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), and Université Toulouse 1 Capitole - UT1 (FRANCE)

Subjects
Certification, Autre, Monotony, Neural network verification, Formal Methods
Abstract

The use of ML technology to design safety-critical systems requires a complete understanding of the neural network's properties. Among the relevant properties in an industrial context, the verification of partial monotony may become mandatory. This paper proposes a method to evaluate the monotony property using a Mixed Integer Linear Programming (MILP) solver. Contrary to the existing literature, this monotony analysis provides a lower and upper bound of the space volume where the property does not hold, that we denote ``Non-Monotonic Space Coverage''. This work has several advantages: (i) our formulation of the monotony property works on discrete inputs, (ii) the iterative nature of our algorithm allows for refining the analysis as needed, and (iii) from an industrial point of view, the results of this evaluation are valuable to the aeronautical domain where it can support the certification demonstration. We applied this method to an avionic case study (braking distance estimation using a neural network) where the verification of the monotony property is of paramount interest from a safety perspective.

Published
2022

5. Regarding the COVID-19 crisis from a systems engineering perspective

Author

Pantano-Calderón, Santiago, Baron, Claude, Chaudemar, Jean-Charles, Vareilles, Élise, Vingerhoeds, Rob, Équipe Méthodes et Algorithmes en Commande (LAAS-MAC), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Équipe Ingénierie Système et Intégration (LAAS-ISI), Département d'Ingénierie des Systèmes Complexes (DISC), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT), ISCRAM, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and Pantano-Calderón, Santiago

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, [SHS.STAT]Humanities and Social Sciences/Methods and statistics, Autre, [SHS.STAT] Humanities and Social Sciences/Methods and statistics, Modeling, [SHS.GESTION]Humanities and Social Sciences/Business administration, COVID-19, [SHS.GESTION] Humanities and Social Sciences/Business administration, Simulation, Crisis, Holistic approach
Abstract

International audience; In the beginning of 2022, the world is still fighting the crisis caused by the COVID-19 outbreak. The scientific community is still dedicating significant efforts to identify which are the better strategies to mitigate the pandemic and establish how and when to apply them. Modeling and simulation are a common method to replicate and foresee the behavior of the epidemic curve, but traditional analytical models are not capable to explain and reproduce the real evolution of the number of infections and deaths as they only concentrate in the epidemiological aspects of the virus. The COVID-19 crisis has an impact in all fundamental levels of society, and this is the reason why its modeling requires a global perspective and a holistic approach. Though the engineering scope is not common in the study of public health crises, this paper concludes that some engineering tools such as systems analysis and control theory may be the answer to build a high-fidelity model to support the decision-making facing the emergency.

Published
2022

6. Improving the Estimation of the Wavenumber Spectra From Altimeter Observations

Author

Amandine Guillot, Olivier Besson, Sophie Le Gac, Corinne Mailhes, Centre National d'Études Spatiales - CNES (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (FRANCE), and Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (Toulouse, France)

Subjects
Scale (ratio), Anomaly (natural sciences), Spectral density, Estimator, Autoregressive (AR) model, Spectral analysis, Autoregressive model, Temporal resolution, Spectral slope, General Earth and Planetary Sciences, Traitement du signal et de l'image, Electrical and Electronic Engineering, Frequency warping, Sea-level anomaly (SLA), Slope estimation, Mathematics, Parametric statistics, Remote sensing
Abstract

Satellite altimeters provide sea-level measurements along satellite track. A mean profile based on the measurements averaged over a time period is then subtracted to estimate the sea-level anomaly (SLA). In the spectral domain, SLA is characterized by a power spectral density (PSD) whose slope in a log–log scale is a parameter of great interest for ocean monitoring. Estimation of this spectral slope is usually done through a cumulated periodogram using a large number of signal samples. The location and dates of the data induce the spatial and temporal resolution of the slope estimates. To improve this resolution, this article studies a new parametric method based on an autoregressive model combined with a warping of the frequency scale (denoted as ARWARP). This ARWARP model provides a PSD estimate, with a lower variance than the classical Fourier-based ones and is reliable in the case of a small sample number. To give a reference in the performance of the SLA slope estimation, the corresponding Cramér–Rao bound is derived. Then, rather than performing linear regression on the spectral estimates, a new estimator of the slope is suggested, based on a model fitting of the PSD. A statistical validation is proposed on simulated SLA signals, showing the performance of slope estimation using this ARWARP spectral estimator, compared to classical Fourier-based methods. Application to Sentinel-3 real data highlights the main advantage of the ARWARP model, making possible SLA slope estimation on a short signal segment, i.e., with a high spatial and/or temporal resolution.

Published
2022

7. Towards Automating Cryptographic Hardware Implementations: a Case Study of HQC

Author

Aguilar-Melchor, Carlos, Deneuville, Jean-Christophe, Dion, Arnaud, Howe, James, Malmain, Romain, Migliore, Vincent, Nawan, Mamuri, Nawaz, Kashif, Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole Nationale de l'Aviation Civile - ENAC (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Institut Eurécom (FRANCE), SandboxAQ (USA), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Technology Innovation Institute - TII (United Arab Emirates), Département d'Ingénierie des Systèmes Complexes - DISC (Toulouse, France), Laboratoire d'Analyse et d'Architecture des Systèmes - LAAS (Toulouse, France), SandboxAQ, Ecole Nationale de l'Aviation Civile (ENAC), Département d'Ingénierie des Systèmes Complexes (DISC), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Eurecom [Sophia Antipolis], Équipe Tolérance aux fautes et Sûreté de Fonctionnement informatique (LAAS-TSF), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), and Technology Innovation Institute (TII)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, HLS, Autre, HQC, Cryptography, FPGA
Abstract

International audience; While hardware implementations allow the production of highly efficient and performance oriented designs, exploiting features such as parallelization, their longer time to code and implement often bottlenecks rapid prototyping. On the other hand, high-level synthesis (HLS) tools allow for faster experimentation of software code to a hard- ware platform while demonstrating a reasonable extrapolation of the expected hardware behavior. In this work, we attempt to show a rapid, fast prototyping of the well known HQC algorithm, using HLS, and show how with a modification of certain parameters, varying degrees of comparable results can be obtained. These results, in turn, could be used as a guide for HDL-RTL developers to enhance their designs and better prototyping time in the future. Additionally, we also demonstrate that it is possible to benefit from HQC’s versatility; by achieving a low hardware footprint whilst also maintaining good performances, even on low-cost FPGA devices, which we demonstrate on the well known Artix-7 xc7a100t-ftg256-1.

Published
2022

8. Séquences pilotes optimales pour la synchronisation de récepteurs FTN en présence de contamination par les données

Author

Mounsif, Leila, Roque, Damien, Poulliat, Charly, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), and Université Toulouse 1 Capitole - UT1 (FRANCE)

Subjects
Faster-than-Nyquist, Autre, Séquences pilotes, Contamination des pilotes, Borne de Cramér-Rao
Abstract

Dans cette étude, nous construisons des séquences pilotes pour la synchronisation en délai et en phase de récepteurs monoporteuses Faster-than-Nyquist (FTN). Nous obtenons des solutions analytiques basées sur la minimisation de la borne de Cramér-Rao des paramètres d'intérêt, en discutant notamment de l'impact de la densité de transmission. Nous évaluons ensuite le problème de la contamination des pilotes par les données, y compris en présence d'une synchronisation en fréquence grossière non-aidée par les données.

Published
2022

9. Cacol: A zero overhead and non-intrusive double caching mitigation system

Author

Grégoire Todeschi, Alain Tchana, Boris Teabe, Daniel Hagimont, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National de la Recherche en Informatique et en Automatique - INRIA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Université Côte d'Azur (FRANCE), Système d’exploitation, systèmes répartis, de l’intergiciel à l’architecture (IRIT-SEPIA), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Laboratoire d'Informatique, Signaux, et Systèmes de Sophia Antipolis (I3S), Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Software_OPERATINGSYSTEMS, Computer Networks and Communications, Computer science, Double caching, Système d'exploitation, Réseaux et télécommunications, 02 engineering and technology, computer.software_genre, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], Architectures Matérielles, Virtualization, Server, 0202 electrical engineering, electronic engineering, information engineering, Overhead (computing), Page cache, Hardware_MEMORYSTRUCTURES, 020206 networking & telecommunications, Hypervisor, Resource (Windows), Systèmes embarqués, Zero (linguistics), Hardware and Architecture, Operating system, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, 020201 artificial intelligence & image processing, [INFO.INFO-OS]Computer Science [cs]/Operating Systems [cs.OS], computer, Software
Abstract

International audience; In a virtualized server, a page cache (which caches I/O data) is managed in both the hypervisor and the guest Operating System (OS). This leads to a well-known issue called double caching. Double caching is the presence of the same data in both the hypervisor page cache and guest OS page caches. Some experiments we performed show that almost 64% of the hypervisor page cache content is also present in guest page caches.Therefore, double caching is a huge source of memory waste in virtualized servers, particularly when I/O disk-intensive workloads are executed (which is common in today’s data centers). Knowing that memory is the limiting resource for workload consolidation, double caching is a critical issue.This paper presents a novel solution (called Cacol) to avoid double caching. Unlike existing solutions, Cacol is not intrusive as it does not require guest OS modification and induces very little performance overhead for user applications. We implemented Cacol in KVM hypervisor, a very popular virtualization system. We evaluated Cacol and compared it with Linux default solutions. The results confirm the advantages (no guest modification and no overhead) of Cacol against existing solutions.

Published
2020

10. Derivation of Heard-of Predicates from Elementary Behavioral Patterns

Author

Aurélie Hurault, Philippe Quéinnec, Adam Shimi, Assistance à la Certification d’Applications DIstribuées et Embarquées (IRIT-ACADIE), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), ANR-16-CE25-0006,PARDI,Vérification de systèmes distribués paramétrés(2016), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), and Université Toulouse 1 Capitole - UT1 (FRANCE)

Subjects
FOS: Computer and information sciences, [INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Theoretical computer science, Computer science, Failures, 0102 computer and information sciences, 02 engineering and technology, [INFO.INFO-SE]Computer Science [cs]/Software Engineering [cs.SE], Fault (power engineering), Interface homme-machine, 01 natural sciences, Field (computer science), Article, Message-passing, [INFO.INFO-CR]Computer Science [cs]/Cryptography and Security [cs.CR], Architectures Matérielles, Simple (abstract algebra), 0202 electrical engineering, electronic engineering, information engineering, Asynchronous rounds, Génie logiciel, [INFO.INFO-HC]Computer Science [cs]/Human-Computer Interaction [cs.HC], Repetition (rhetorical device), Message passing, Behavioral pattern, Modélisation et simulation, 16. Peace & justice, Systèmes embarqués, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Heard-of model, Computer Science - Distributed, Parallel, and Cluster Computing, 010201 computation theory & mathematics, Cryptographie et sécurité, 020201 artificial intelligence & image processing, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, Distributed, Parallel, and Cluster Computing (cs.DC)
Abstract

There are many models of distributed computing, and no unifying mathematical framework for considering them all. One way to sidestep this issue is to start with simple communication and fault models, and use them as building blocks to derive the complex models studied in the field. We thus define operations like union, succession or repetition, which makes it easier to build complex models from simple ones while retaining expressivity. To formalize this approach, we abstract away the complex models and operations in the Heard-Of model. This model relies on (possibly asynchronous) rounds; sequence of digraphs, one for each round, capture which messages sent at a given round are received before the receiver goes to the next round. A set of sequences, called a heard-of predicate,defines the legal communication behaviors -- that is to say, a model of communication. Because the proposed operations behave well with this transformation of operational models into heard-of predicates, we can derive bounds, characterizations, and implementations of the heard-of predicates for the constructions., Full version of a paper accepted to FORTE 2020

Published
2020

11. Elderly monitoring system in a smart city environment using LoRa and MQTT

Author

Abdennaceur Kachouri, Thierry Val, Abdelfatteh Lachtar, Laboratoire d'électronique et des technologies de l'Information [Sfax] (LETI), École Nationale d'Ingénieurs de Sfax | National School of Engineers of Sfax (ENIS), Réseaux, Mobiles, Embarqués, Sans fil, Satellites (IRIT-RMESS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse - Jean Jaurès (UT2J), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), École Nationale d'Ingénieurs de Sfax - ENIS (TUNISIA), and Université de Sfax (TUNISIA)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Walking stick, Computer science, Internet of Things, Interoperability, Système d'exploitation, Réseaux et télécommunications, Context (language use), 02 engineering and technology, 01 natural sciences, Industrial and Manufacturing Engineering, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], Architectures Matérielles, Smart city, 11. Sustainability, 0202 electrical engineering, electronic engineering, information engineering, Telemetry, Open systems, Middleware, Patient monitoring, MQTT, business.industry, Node (networking), 010401 analytical chemistry, 020206 networking & telecommunications, Systèmes embarqués, 0104 chemical sciences, Machine to machine, Queueing theory, Geriatrics, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, [INFO.INFO-OS]Computer Science [cs]/Operating Systems [cs.OS], business, Message queue, Protocols, Smart cities, Computer network
Abstract

International audience; With the rapid surge of M-Health and smart city systems, the need to accommodate sensors and actuators to achieve effective automation turns out to be imposed, for an efficient machine-to-machine communication to be maintained. In this regard, the key elements necessary for a successful M-Health system to take place are discovered to be the power consumption and interoperability maintaining factors. In this context, the present study is conducted to devise a special elderly tracking and monitoring system, closely connected to a walking stick device. The proposed design involves a cane cased transmitter node, enabling to send data related to the position and the state of the elderly to a base station, through implementation of the LoRa technology. The latter would then apply the message queuing telemetry transport (MQTT) protocol to interact with the environment once a fall proves to take place. For the purpose of evaluating the advanced design associated coverage range and power consumption rate, as enhanced via LoRa network, several experimental tests have been administered. The achieved results appear to reveal that the suggested architecture recorded average covered area turns out to be of the rate of 6 km2.

Published
2020

12. An algorithm for the minimization of nonsmooth nonconvex functions using inexact evaluations and its worst-case complexity

Author

Ehouarn Simon, Philippe L. Toint, Serge Gratton, Algorithmes Parallèles et Optimisation (IRIT-APO), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Namur Center for Complex Systems [Namur] (NaXys), Université de Namur [Namur] (UNamur), ANR-19-P3IA-0004,ANITI,Artificial and Natural Intelligence Toulouse Institute(2019), ANR-11-IDEX-0002,UNITI,Université Fédérale de Toulouse(2011), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and Université de Namur - UNamur (BELGIQUE)

Subjects
Evaluation complexity, Hessian matrix, evaluation complexity, nonconvex optimization, General Mathematics, MathematicsofComputing_NUMERICALANALYSIS, Mathematics::Optimization and Control, 0211 other engineering and technologies, 010103 numerical & computational mathematics, 02 engineering and technology, 01 natural sciences, Regularization (mathematics), inexact evaluations, Statistics::Machine Learning, symbols.namesake, Inexact evaluations, TheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITY, Worst-case complexity, 0101 mathematics, Mathematics, 021103 operations research, Numerical analysis, nonsmooth problems, Intelligence artificielle, composite functions, Stationary point, Nonconvex optimization, symbols, Adaptive regularization, Minification, Algorithm, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA], Software
Abstract

An adaptive regularization algorithm using inexact function and derivatives evaluations is proposed for the solution of composite nonsmooth nonconvex optimization. It is shown that this algorithm needs at most $$O(|\log (\epsilon )|\,\epsilon ^{-2})$$ evaluations of the problem’s functions and their derivatives for finding an $$\epsilon $$ -approximate first-order stationary point. This complexity bound therefore generalizes that provided by Bellavia et al. (Theoretical study of an adaptive cubic regularization method with dynamic inexact Hessian information. arXiv:1808.06239 , 2018) for inexact methods for smooth nonconvex problems, and is within a factor $$|\log (\epsilon )|$$ of the optimal bound known for smooth and nonsmooth nonconvex minimization with exact evaluations. A practically more restrictive variant of the algorithm with worst-case complexity $$O(|\log (\epsilon )|+\epsilon ^{-2})$$ is also presented.

Published
2020

13. Performances Analysis of a System of Localization by Angle of Arrival UWB Radio

Author

Salick Diagne, Abdou Karim Farota, Thierry Val, Ognadon Assogba, Bouya Diop, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Université Gaston Berger de Saint-Louis - UGB (SENEGAL), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), Université Gaston Berger de Saint-Louis Sénégal (UGB), Réseaux, Mobiles, Embarqués, Sans fil, Satellites (IRIT-RMESS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, and Université Toulouse - Jean Jaurès (UT2J)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Computer science, Real-time computing, Système d'exploitation, 0211 other engineering and technologies, Réseaux et télécommunications, Context (language use), 02 engineering and technology, Signal, Set (abstract data type), [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], UWB, Architectures Matérielles, Angle of arrival, 0202 electrical engineering, electronic engineering, information engineering, PDoA, 021103 operations research, Observational error, Bandwidth (signal processing), 020206 networking & telecommunications, Systèmes embarqués, Angle of Arrival (AoA), Localization, Temporal resolution, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, [INFO.INFO-OS]Computer Science [cs]/Operating Systems [cs.OS], Actuator
Abstract

International audience; The increasingly widespread use of sensor and actuator networks and in general of the Internet of Things (IoT) in several areas of precision, imposes upon localization systems that can often equip them with a robust and more precise localization. It is in this sense that UWB technology has proved to be one of the most powerful communication technologies for these localization systems; thanks, in particular to the bandwidth occupied instantaneously by the signal allowing a very fine temporal resolution. Constructors have set up localization kits based on various technologies. These kits facilitate in a way the work of localization of users. In this paper, we present results on the performance study of the Decawave PDoA Kit. This Kit uses the PDoA (Phase Difference of Arrival) to determine the Angle of Arrival (AoA) parameter with UWB technology. This study is in context of localization by AoA for an application to protect agricultural crops against grain-eating birds. The results of the study show overall AoA measurement errors around 10 degrees in an ideal environment.

Published
2020

14. On Iterative Solution of the Extended Normal Equations

Author

Xavier Vasseur, Henri Calandra, Serge Gratton, Elisa Riccietti, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Total (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), TOTAL-Scientific and Technical Center Jean Féger (CSTJF), TOTAL FINA ELF, Algorithmes Parallèles et Optimisation (IRIT-APO), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Département d'Ingénierie des Systèmes Complexes (DISC), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), and ANR-19-P3IA-0004,ANITI,Artificial and Natural Intelligence Toulouse Institute(2019)

Subjects
Linear system, Linear systems, 010103 numerical & computational mathematics, Conjugate gradient method, Special class, Mathématiques générales, 01 natural sciences, 010101 applied mathematics, Combinatorics, Matrix (mathematics), [MATH.MATH-GM]Mathematics [math]/General Mathematics [math.GM], Forward error, Least squares problems, 0101 mathematics, Analysis, Mathematics
Abstract

International audience; Given a full-rank matrix $A \in \mathbb{R}^{m\times n}$ ($m\geq n$), we consider a special class of linear systems $A^T\! Ax=A^T\! b+c$ with $x, c \in \mathbb{R}^{n}$ and $b \in \mathbb{R}^{m}$, which we refer to as the extended normal equations. The occurrence of $c$ gives rise to a problem with a different conditioning from the standard normal equations and prevents direct application of standard methods for least squares. Hence, we seek more insights on theoretical and practical aspects of the solution of such problems. We propose an explicit formula for the structured condition number, which allows us to compute a more accurate estimate of the forward error than the standard one used for generic linear systems, which does not take into account the structure of the perturbations. The relevance of our estimate is shown on a set of synthetic test problems. Then, we propose a new iterative solution method that, as in the case of normal equations, takes advantage of the structure of the system to avoid unstable computations such as forming $A^T\! A$ explicitly. Numerical experiments highlight the increased robustness and accuracy of the proposed method compared to standard iterative methods. It is also found that the new method can compare to standard direct methods in terms of solution accuracy.

Published
2020

15. Estimation of linear operators from scattered impulse responses

Author

Paul Escande, Jérémie Bigot, Pierre Weiss, Institut de Mathématiques de Bordeaux (IMB), Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS), Département d'Ingénierie des Systèmes Complexes (DISC), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Institut des Technologies Avancées en sciences du Vivant (ITAV), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut de Mathématiques de Toulouse UMR5219 (IMT), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), MODIM PRES ToulouseOPTIMUS RITC Toulouse, Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Bordeaux INP - BINP (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université de Bordeaux 1 (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Université de Bordeaux 2 - Victor Segalen (FRANCE), Université de Bordeaux (FRANCE), PRIMO (ITAV), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut des Technologies Avancées en sciences du Vivant (ITAV), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut des Technologies Avancées en sciences du Vivant (ITAV)

Subjects
FOS: Computer and information sciences, 47A58, 41A15, 41A25, 68W25, 62H12, 65T60, 94A20, 010103 numerical & computational mathematics, Impulse (physics), Estimator, 01 natural sciences, estimator, Radial basis functions, convergence rate, Operator (computer programming), Autre, [MATH.MATH-ST]Mathematics [math]/Statistics [math.ST], Scattered approximation, Radial basis function, Minimax, 41A25, ComputingMilieux_MISCELLANEOUS, Mathematics, AMS classifications: 47A58, Applied Mathematics, radial basis functions, Numerical Analysis (math.NA), Rate of convergence, [INFO.INFO-IT]Computer Science [cs]/Information Theory [cs.IT], symbols, 62H12, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA], Smoothing, minimax, Computer Science - Information Theory, 65T60, Mathematics - Statistics Theory, Statistics Theory (math.ST), symbols.namesake, numerical, FOS: Mathematics, Applied mathematics, Mathematics - Numerical Analysis, 0101 mathematics, Numerical complexity, Reproducing Kernel Hilbert Spaces, Information Theory (cs.IT), 010102 general mathematics, Integral operator, Hilbert space, [MATH.MATH-IT]Mathematics [math]/Information Theory [math.IT], scattered approximation, 68W25, 94A20, Convergence rate, complexity, 41A15
Abstract

International audience; We provide a new estimator of integral operators with smooth kernels, obtained from a set of scattered and noisy impulse responses. The proposed approach relies on the formalism of smoothing in reproducing kernel Hilbert spaces and on the choice of an appropriate regularization term that takes the smoothness of the operator into account. It is numerically tractable in very large dimensions. We study the estimator's robustness to noise and analyze its approximation properties with respect to the size and the geometry of the dataset. In addition, we show minimax optimality of the proposed estimator.

Published
2019

16. Effects of oral and oropharyngeal cancer on speech intelligibility using acoustic analysis: Systematic review

Author

Julien Pinquier, Renée Speyer, Timothy Pommée, Mathieu Balaguer, Virginie Woisard, Jérôme Farinas, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Centre Hospitalier Universitaire de Toulouse - CHU Toulouse (FRANCE), University of Oslo (NORWAY), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), Centre Hospitalier Universitaire de Toulouse (CHU Toulouse), Équipe Structuration, Analyse et MOdélisation de documents Vidéo et Audio (IRIT-SAMoVA), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Toulouse Mind & Brain Institut (TMBI), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Unité de Recherche Interdisciplinaire Octogone-Lordat (Octogone-Lordat), Université de Toulouse (UT)-Université de Toulouse (UT), Faculty of Educational Sciences [Oslo], University of Oslo (UiO), Agence Nationale de la Recherche, Grant/Award Number: ANR‐18‐CE45‐0008, Hospitals of Toulouse, PNRIA, ANR-18-CE45-0008,RUGBI,Recherche d'unités linguistiques pertinentes pour améliorer la mesure de l'intelligibilité de la parole altérée par des troubles de production pathologique(2018), European Project: 766287, CHU Toulouse [Toulouse], Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
media_common.quotation_subject, Speech recognition, [SDV.CAN]Life Sciences [q-bio]/Cancer, Functional impact, Intelligibility (communication), behavioral disciplines and activities, Speech Acoustics, Machine Learning, 03 medical and health sciences, 0302 clinical medicine, Speech Production Measurement, Vowel, Perception, otorhinolaryngologic diseases, medicine, Humans, Speech, Head and neck cancer, speech, intelligibility, acoustics, head and neck cancer, oncology, Cancer, media_common, [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], Spectral moments, business.industry, Speech Intelligibility, Informatique et langage, Acoustics, 030206 dentistry, 3. Good health, Oropharyngeal Neoplasms, Systematic review, Oncology, Otorhinolaryngology, 030220 oncology & carcinogenesis, Speech disorder, medicine.symptom, Nasalance, business, Intelligibility, psychological phenomena and processes
Abstract

Background The development of automatic tools based on acoustic analysis allows to overcome the limitations of perceptual assessment for patients with head and neck cancer. The aim of this study is to provide a systematic review of literature describing the effects of oral and oropharyngeal cancer on speech intelligibility using acoustic analysis. Methods Two databases (PubMed and Embase) were surveyed. The selection process, according to the preferred reporting items for systematic reviews and meta‐analyses (PRISMA) statement, led to a final set of 22 articles. Results Nasalance is studied mainly in oropharyngeal patients. The vowels are mostly studied using formant analysis and vowel space area, the consonants by means of spectral moments with specific parameters according to their phonetic characteristic. Machine learning methods allow classifying “intelligible” or “unintelligible” speech for T3 or T4 tumors. Conclusions The development of comprehensive models combining different acoustic measures would allow a better consideration of the functional impact of the speech disorder.

Published
2019

17. Optimal Pilot Sequences for Phase and Timing Synchronization in FTN Systems

Author

Mounsif, Leila, Roque, Damien, Poulliat, Charly, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), and Université Toulouse 1 Capitole - UT1 (FRANCE)

Subjects
pilot sequences, timing estimation, phase estimation, Cramér Rao bound (CRB), Autre, Synchronization, Faster-than-Nyquist (FTN)
Abstract

In this paper, we study the joint phase and timing estimation problem in Faster-than-Nyquist (FTN) systems. We use the Cramér-Rao lower bound (CRB) as a cost function to design optimal pilot sequences subject to an energy constraint. We rely on harmonic approximations of the bound to establish closed-form relations between the ultimate synchronization performance and the transmitted waveform characteristics (i.e., pulse shaping filter and signaling density). We show that increasing the symbol rate at fixed bandwidth is beneficial to phase estimation and detrimental to timing synchronization. Therefore, we propose a joint timing/phase pilot design to accommodate this trade-off. Lastly, we illustrate the strengths of the proposed pilots with respect to traditional Zadoff-Chu sequences in presence of a residual carrier frequency offset.

Published
2021

18. How to introduce expert feedback in one-class support vector machines for anomaly detection?

Author

Marc Spigai, Julien Lesouple, Jean-Yves Tourneret, Cedric Baudoin, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Thales (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (FRANCE), Télécommunications Spatiales et Aéronautiques - Telecommunications for Space ant Aeronautics (TéSA), Laboratoire de recherche coopératif dans les télécommunications spatiales et aéronautiques (TESA), Thales Alenia Space (TAS), THALES, CoMputational imagINg anD viSion (IRIT-MINDS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Computer science, 02 engineering and technology, Semi-supervised learning, Anomaly detection, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Machine learning, 0202 electrical engineering, electronic engineering, information engineering, Traitement du signal et de l'image, Electrical and Electronic Engineering, Hyperparameter, Support vector machines, business.industry, Detector, 020206 networking & telecommunications, Pattern recognition, Class (biology), Support vector machine, ComputingMethodologies_PATTERNRECOGNITION, Control and Systems Engineering, Signal Processing, Benchmark (computing), 020201 artificial intelligence & image processing, Computer Vision and Pattern Recognition, Artificial intelligence, Anomaly (physics), business, Software
Abstract

International audience; Anomaly detection consists of detecting elements of a database that are different from the majority of normal data. The majority of anomaly detection algorithms considers unlabeled datasets. However, in some applications, labels associated with a subset of the database (coming for instance from expert feed- back) are available providing useful information to design the anomaly detector. This paper studies a semi-supervised anomaly detector based on support vector machines, which takes the best of existing supervised and unsupervised support vector machines algorithms. The proposed algorithm allows the maximum proportion of vectors detected as anomalies and the maximum proportion of errors in the supervised data to be controlled, through two hyperparameters defining these proportions. Simulations conducted on various benchmark datasets show the interest of the proposed semi-supervised anomaly detection method.

Published
2021

19. A variational marginalized particle filter for jump Markov nonlinear systems with unknown transition probabilities

Author

Jean-Yves Tourneret, Cheng Cheng, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Northwestern Polytechnical University (CHINA), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), Northwestern Polytechnical University [Xi'an] (NPU), CoMputational imagINg anD viSion (IRIT-MINDS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Posterior probability, Markov process, 02 engineering and technology, Bayesian inference, Conjugate prior, Jump Markov nonlinear systems, symbols.namesake, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, 0202 electrical engineering, electronic engineering, information engineering, Applied mathematics, Traitement du signal et de l'image, Electrical and Electronic Engineering, Mathematics, Markov chain, State vector, 020206 networking & telecommunications, Extended factorized approximation, Nonlinear system, Control and Systems Engineering, Signal Processing, symbols, Marginalized particle filter, 020201 artificial intelligence & image processing, Computer Vision and Pattern Recognition, Particle filter, Variational inference, Software
Abstract

International audience; This paper studies a new variational marginalized particle filter for jointly estimating the state and the system mode parameters of jump Markov nonlinear systems. Contrary to the Markovian assumption usu- ally considered to model the evolution of the system modes, we introduce conjugate prior distributions for the system mode parameters. The joint posterior distribution of the state and system mode parame- ters is then marginalized with respect to the mode variables. The remaining state vector is sampled us- ing a sequential Monte Carlo algorithm, and the mode parameters are sampled using variational Bayesian inference. In order to obtain analytical solutions for the different variational distributions, we use an extended factorized approximation simplifying the variational distributions. A comprehensive simulation study is conducted to compare the performance of the proposed approach with the state-of-the-art for a modified nonlinear benchmark model and maneuvering target tracking scenarios.

Published
2021

20. Oxygen supply management to intensify wastewater treatment by a microbial electrochemical snorkel

Author

Alain Bergel, Morgane Hoareau, Benjamin Erable, Luc Etcheverry, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Laboratoire de Génie Chimique (LGC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
electroactive biofilm, microbial electrochemical system, microbial fuel cell -bioelectrochemical system, [SDV.BIO]Life Sciences [q-bio]/Biotechnology, Microbial fuel cell, General Chemical Engineering, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, Cathodic protection, microbial fuel cell, [CHIM.GENI]Chemical Sciences/Chemical engineering, Electrochemistry, Bioreactor, Génie chimique, Organic matter, Génie des procédés, 0105 earth and related environmental sciences, chemistry.chemical_classification, [SDE.IE]Environmental Sciences/Environmental Engineering, bioelectrochemical system, 021001 nanoscience & nanotechnology, Pulp and paper industry, Anoxic waters, 6. Clean water, Anode, chemistry, Sewage treatment, Aeration, 0210 nano-technology, Bioremediation
Abstract

International audience; The microbial electrochemical snorkel (MES) is a low-cost, low-maintenance technology that could considerably reduce wastewater treatment costs by reducing the need for aeration. An MES is a single electrode. The lower part, in the anoxic zone of the bioreactor, oxidizes organic matter by transferring electrons to the electrode. The upper part, in the oxic zone, releases the electrons by reducing dissolved oxygen. This study gives new insights into the correlation between the MES potential, the concentration of dissolved oxygen and COD abatement, thus enabling practical rules to be extracted for running the MES in optimal conditions, particularly for adjusting the aeration zone and frequency. Here, aeration promoted the cathodic reaction and increased the MES potential to a maximum (0.0 to 0.1 V/SCE). After aeration stopped, the potential dropped to a minimum (< -0.4 V/SCE). With 26 cm high MESs, sequential aeration at the top was not sufficient to support an effective cathodic zone, while aeration at the bottom was detrimental to the formation of the microbial anode. With MESs 48 cm high and aeration set up in the highest quarter, 30 minutes of aeration every 4.5 hours gave potential variations that were stable for weeks. The MESs continued to oxidize organic matter 30 minutes after the aeration had stopped. In this period, the MESs removed 3 to 6.3 times more COD than the control reactors. Increasing the electrode capacitance is therefore suggested as an effective way to further decrease the aeration cost by decreasing the aeration frequency.

Published
2021

21. Formal verification of space systems designed with TASTE

Author

Dragomir, I, Bozga, M, Ober, Iulian, Silveira, D, Jorge, T, Alaña, E, Perrotin, M, GMV Space (GMV), GMV, VERIMAG (VERIMAG - IMAG), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), GMVIS Skysoft SA (PORTUGAL), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Grenoble Alpes - UGA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), ESA - ESTEC (NETHERLANDS), and GMV Aerospace and Defence S.A. (SPAIN)

Subjects
Software Engineering (cs.SE), FOS: Computer and information sciences, Computer Science - Software Engineering, MBSE, TASTE, model checking, Autre, [INFO.INFO-SE]Computer Science [cs]/Software Engineering [cs.SE]
Abstract

International audience; Model-Based Systems Engineering (MBSE) is a development approach aiming to build correct-by-construction systems, provided the use of clear, unambiguous and complete models to describe them along the design process. The approach is supported by several engineering tools that automate the development steps, for example the production of code, documentation, test cases and more. TASTE [1] is pragmatic MBSE toolset supported by ESA that encapsulates several technologies to design a system (data modelling, architecture modelling, behaviour modelling/implementation), to automatically generate the binary application(s), and to validate it. One topic left open in TASTE is the formal verification of a system design with respect to specified properties. In this paper we describe our approach based on the IF model-checker [4] to enable the formal verification of properties on TASTE designs. The approach is currently under development in the ESA MoC4Space project.

Published
2021

22. Regularization via Deep Generative Models: an Analysis Point of View

Author

Thomas Oberlin, Mathieu Verm, Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Signal et Communications (IRIT-SC), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, IEEE Signal Processing Society, ANR-19-P3IA-0004,ANITI,Artificial and Natural Intelligence Toulouse Institute(2019), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), and Université Toulouse 1 Capitole - UT1 (FRANCE)

Subjects
FOS: Computer and information sciences, Inverse problems, Deblurring, Computer Science - Machine Learning, Computer science, Computer Vision and Pattern Recognition (cs.CV), [INFO.INFO-OH]Computer Science [cs]/Other [cs.OH], Inpainting, Computer Science - Computer Vision and Pattern Recognition, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Initialization, 02 engineering and technology, Data-driven priors, Regularization (mathematics), Image (mathematics), Machine Learning (cs.LG), Autre, Regularization, 0202 electrical engineering, electronic engineering, information engineering, FOS: Electrical engineering, electronic engineering, information engineering, Artificial neural network, Image and Video Processing (eess.IV), Generative models, 020207 software engineering, Inverse problem, Electrical Engineering and Systems Science - Image and Video Processing, Generative model, Deep regularization, Computer Science::Computer Vision and Pattern Recognition, 020201 artificial intelligence & image processing, Algorithm, Estimation
Abstract

International audience; This paper proposes a new way of regularizing an inverse problem in imaging (e.g., deblurring or inpainting) by means of a deep generative neural network. Compared to end-to-end models, such approaches seem particularly interesting since the same network can be used for many different problems and experimental conditions, as soon as the generative model is suited to the data. Previous works proposed to use a synthesis framework, where the estimation is performed on the latent vector, the solution being obtained afterwards via the decoder. Instead, we propose an analysis formulation where we directly optimize the image itself and penalize the latent vector. We illustrate the interest of such a formulation by running experiments of inpainting, deblurring and super-resolution. In many cases our technique achieves a clear improvement of the performance and seems to be more robust, in particular with respect to initialization.

Published
2021

23. Phase recovery with Bregman divergences for audio source separation

Author

Pierre-Hugo Vial, Cédric Févotte, Paul Magron, Thomas Oberlin, Signal et Communications (IRIT-SC), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Toulouse Mind & Brain Institut (TMBI), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Centre National de la Recherche Scientifique (CNRS), ANR-19-P3IA-0004,ANITI,Artificial and Natural Intelligence Toulouse Institute(2019), European Project: CoG-6681839,ERC FACTORY, Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), and Université Toulouse 1 Capitole - UT1 (FRANCE)

Subjects
FOS: Computer and information sciences, Sound (cs.SD), Computer science, Audio source separation, Speech enhancement, projected gradient descent, Computer Science - Sound, Phase recovery, symbols.namesake, Quadratic equation, [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Audio and Speech Processing (eess.AS), FOS: Electrical engineering, electronic engineering, information engineering, Source separation, Projected gradient descent, Short-time Fourier transform, audio source separation, Informatique et langage, Bregman divergences, Time–frequency analysis, Fourier transform, Computer Science::Sound, [INFO.INFO-SD]Computer Science [cs]/Sound [cs.SD], symbols, Spectrogram, speech enhancement, Gradient descent, Algorithm, Electrical Engineering and Systems Science - Audio and Speech Processing
Abstract

International audience; Time-frequency audio source separation is usually achieved by estimating the short-time Fourier transform (STFT) magnitude of each source, and then applying a phase recovery algorithm to retrieve time-domain signals. In particular, the multiple input spectrogram inversion (MISI) algorithm has shown good performance in several recent works. This algorithm minimizes a quadratic reconstruction error between magnitude spectrograms. However, this loss does not properly account for some perceptual properties of audio, and alternative discrepancy measures such as beta-divergences have been preferred in many settings. In this paper, we propose to reformulate phase recovery in audio source separation as a minimization problem involving Bregman divergences. To optimize the resulting objective, we derive a projected gradient descent algorithm. Experiments conducted on a speech enhancement task show that this approach outperforms MISI for several alternative losses, which highlights their relevance for audio source separation applications.

Published
2021

24. The efficiency of organizational withdrawal vs commitment

Author

Sibertin-Blanc, Christophe, Terán, Oswaldo, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Universidad de Los Andes (VENEZUELA), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)

Subjects
Autre, Social simulation, Organizational commitment, Computational social science, Organizational withdrawal, Organizational withdrawal - Actors, Actors
Abstract

Actors within an organization usually do not behave as expected at design-time. There are diverse reasons for this, notably the actors' motivation and organizational commitment. In this paper, we explore the efficiency of a concrete public organization in the context of the Latin-American culture, to the light of the organizational commitment of its members. In order to evaluate how much each member of the organization is committed, we associate to each one a parameter that quantifies its commitment and we evaluate by simulation the impact of this parameter on its behavior an the organization performance. With a model of the organization as it was intended to operate at its foundation, we proceed to a number of simulations to find the parameter values that yield the actual observed working of the organization. By the way, we found that withdrawn behaviors have much more impact than committed ones.

Published
2021

25. Induced idleness leads to deterministic heavy traffic limits for queue-based random-access algorithms

Author

Florian Simatos, Laurent Miclo, Sem Borst, Eyal Castiel, Philip Whiting, Stochastic Operations Research, Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole des Hautes Etudes en Sciences Sociales - EHESS (FRANCE), Institut national de recherche pour l'agriculture, l'alimentation et l'environnement - INRAE (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Macquarie University (AUSTRALIA), Université Toulouse 1 Capitole - UT1 (FRANCE), Eindhoven University of Technology - TU/e (NETHERLANDS), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Department of mathematics and computing science [Eindhoven], Eindhoven University of Technology [Eindhoven] (TU/e), Institut de Mathématiques de Toulouse UMR5219 (IMT), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Macquarie University, Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Département d'Ingénierie des Systèmes Complexes (DISC), Toulouse School of Economics (TSE), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), and ANR-17-EURE-0010,CHESS,Toulouse Graduate School défis en économie et sciences sociales quantitatives(2017)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, Statistics and Probability, Interference graph, 0211 other engineering and technologies, 02 engineering and technology, Heavy traffic, 01 natural sciences, State space collapse, 010104 statistics & probability, CSMA algorithms, Autre, FOS: Mathematics, Limit (mathematics), 0101 mathematics, B- ECONOMIE ET FINANCE, Stochastic averaging principle, Queue, Scaling, Central limit theorem, Mathematics, 021103 operations research, 60K25 (primary), 60K35 (secondary), Probability (math.PR), 16. Peace & justice, [MATH.MATH-PR]Mathematics [math]/Probability [math.PR], Fully coupled, Statistics, Probability and Uncertainty, Algorithm, Mathematics - Probability, Random access
Abstract

We examine a queue-based random-access algorithm where activation and deactivation rates are adapted as functions of queue lengths. We establish its heavy traffic behavior on a complete interference graph, which turns out to be highly nonstandard in two respects: (1) the scaling depends on some parameter of the algorithm and is not the $N/N^2$ scaling usually found in functional central limit theorems; (2) the heavy traffic limit is deterministic. We discuss how this nonstandard behavior arises from the idleness induced by the distributed nature of the algorithm. In order to prove our main result, we developed a new method for obtaining a fully coupled stochastic averaging principle., Comment: 40 pages

Published
2021

26. Complexity analysis for recent ALOHA random access techniques in satellite communications

Author

Marie-Laure Boucheret, Mathieu Gineste, Jérôme Lacan, Selma Zamoum, Jean-Baptiste Dupe, Centre National de la Recherche Scientifique - CNRS (FRANCE), Ecole Nationale de l'Aviation Civile - ENAC (FRANCE), Laboratoire de recherche textile - GEMTEX (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Direction Générale de l’Aviation Civile - DGAC (FRANCE), Télécommunications Spatiales et Aéronautiques - Telecommunications for Space ant Aeronautics (TéSA), Laboratoire de recherche coopératif dans les télécommunications spatiales et aéronautiques (TESA), Département d'Ingénierie des Systèmes Complexes (DISC), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Signal et Communications (IRIT-SC), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Centre National d'Études Spatiales [Toulouse] (CNES), Thales Alenia Space (TAS), and THALES

Subjects
Computer science, Throughput, 02 engineering and technology, 0203 mechanical engineering, 0202 electrical engineering, electronic engineering, information engineering, Media Technology, Overhead (computing), Traitement du signal et de l'image, [INFO]Computer Science [cs], Electrical and Electronic Engineering, Receiver’s complexity, 020301 aerospace & aeronautics, Network packet, business.industry, Frame (networking), ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS, 020206 networking & telecommunications, Random access, Packet localization, Single antenna interference cancellation, Aloha, Slotted ALOHA protocols, business, Satellite communication, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, Decoding methods, Computer network
Abstract

International audience; In this paper we study the the complexity of packet localization at reception, for recent synchronous Random Access (RA) techniques based on the protocol ALOHA for satellite communications. The promising CRDSA (Contention Resolution Diversity Slotted ALOHA) offers better throughput, in comparison to the traditional slotted ALOHA protocols, thanks to the use of Successive Interference Cancellation (SIC) along with multireplica transmission. MARSALA (Multi-replicA decoding using corRelation baSed locALizAtion) is one of the many variants and enhancement schemes of CRDSA that have been proposed in the literature. It is applied to CRDSA each time a decoding deadlock situation is reached (when no packets can be retrieved by CRDSA). MARSALA first localizes the replicas of collided packets on a chosen reference time slot using correlations. Then it performs coherent signal combination of packet replicas prior to decoding. However, despite the good performance offered by MARSALA, its localization process adds a significant complexity to the receiver in terms of correlation operations. R-SPOTiT (Random Shared POsition Technique for Interfered random Transmissions) mitigates this complexity by introducing a shared information between the receiver and each of the transmitters, about all potential packets' locations on the frame, without any additional signaling overhead. We focus in this paper on the analysis of the total number of correlations which are needed to localize packets' replicas for both MARSALA and R-SPOTiT, with a single or with multiple Gold preambles. This should include preamble detection operations that are performed at CRDSA with a coarse and fine tracking. The results show that the most suitable system to use is the multi-preamble R-SPOTiT with two preambles.

Published
2021

27. Preventing the propagation of a new kind of illegitimate apps

Author

Alain Tchana, Giang Son Tran, Lavoisier Wapet, Daniel Hagimont, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université des Sciences et des Technologies de Hanoi - USTH (VIETNAM), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Système d’exploitation, systèmes répartis, de l’intergiciel à l’architecture (IRIT-SEPIA), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Hanoi University of Science and Technology (HUST), and Institut National Polytechnique (Toulouse) (Toulouse INP)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Focus (computing), Computer Networks and Communications, Computer science, Système d'exploitation, Mobile apps, Réseaux et télécommunications, 020206 networking & telecommunications, 02 engineering and technology, Computer security, computer.software_genre, Systèmes embarqués, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], Detection, Architectures Matérielles, Fake apps, Hardware and Architecture, 0202 electrical engineering, electronic engineering, information engineering, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, 020201 artificial intelligence & image processing, [INFO.INFO-OS]Computer Science [cs]/Operating Systems [cs.OS], computer, Software
Abstract

International audience; A significant amount of apps submitted to mobile market places (MMP) are illegitimate, resulting in a negative publicity for these MMPs. To our knowledge, all scanning solutions in this domain only focus on the detection of illegitimate apps which mimic existing ones. However, recent attack analysis reveal the appearance of a new category of victims: enterprises which did not yet publish their app on the MMP. Thereby, an attacker may be one step ahead and publish a malicious app using the graphic identity of a trusted enterprise. Famous enterprises such as Blackberry, Netflix, and Niantic (Pokemon Go) have been subject of such attacks. We designed and implemented a security check system called IMAD (IllegitimateMobile App Detector) which is able to limit aforementioned attacks. The evaluation results show that IMAD can protect companies from such attacks with an acceptable error rate and at a low cost for MMPs.

Published
2019

28. Multiple description coding technique to improve the robustness of ACELP based coders AMR-WB

Author

Hocine Chaouch, Philippe Marthon, Fatiha Merazka, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université des Sciences et de la Technologie Houari Boumediene - USTHB (ALGERIA), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), and Institut National Polytechnique de Toulouse - INPT (FRANCE)

Subjects
Linguistics and Language, Computer science, Mean opinion score, Speech recognition, Linear prediction, 02 engineering and technology, MUSHRA, 01 natural sciences, Language and Linguistics, ITU-T G.722.2, Packet loss, Robustness (computer science), 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Traitement du signal et de l'image, 010301 acoustics, WB-PESQ, Communication, Multiple description coding, 020206 networking & telecommunications, Algebraic code-excited linear prediction, Markov model, Computer Science Applications, Packet loss concealment, VoIP, Modeling and Simulation, Computer Vision and Pattern Recognition, Software
Abstract

In this paper, a concealment method based on multiple-description coding (MDC) is presented, to improve speech quality deterioration caused by packet loss for algebraic code-excited linear prediction (ACELP) based coders. We apply to the ITU-T G.722.2 coder, a packet loss concealment (PLC) technique, which uses packetization schemes based on MDC. This latter is used with two new designed modes, which are modes 5 and 6 (18,25 and 19,85 kbps, respectively). We introduce our new second-order Markov chain model with four states in order to simulate network losses for different loss rates. The performance measures, with objective and subjective tests under various packet loss conditions, show a significant improvement of speech quality for ACELP based coders. The wideband perceptual evaluation of speech quality (WB-PESQ), enhanced modified bark spectral distortion (EMBSD), mean opinion score (MOS) tests and MUltiple Stimuli with Hidden Reference and Anchor (MUSHRA) for speech extracted from TIMIT database confirm the efficiency of our proposed approach and show a considerable enhancement in speech quality compared to the embedded algorithm in the standard ITU-T G.722.2.

Published
2019

29. Multipath Mitigation for GNSS Positioning in an Urban Environment Using Sparse Estimation

Author

Julien Lesouple, Mohamed Sahmoudi, Jean-Yves Tourneret, Thierry Robert, Willy Vigneau, Télécommunications Spatiales et Aéronautiques - Telecommunications for Space ant Aeronautics (TéSA), Laboratoire de recherche coopératif dans les télécommunications spatiales et aéronautiques (TESA), Centre National d'Etudes Spatiales - Direction Des Lanceurs. (CNES), Département Electronique, Optronique et Signal (DEOS), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), CoMputational imagINg anD viSion (IRIT-MINDS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), M3 Systems (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Direction Générale de l’Aviation Civile - DGAC (FRANCE), Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (FRANCE), and Département d'Electronique, Optronique et Signal - DEOS (Toulouse, France)

Subjects
050210 logistics & transportation, Multipath mitigation, GNSS, Estimation theory, Computer science, Mechanical Engineering, 05 social sciences, Clock drift, LASSO, Regularization (mathematics), Reweighted-l1 algorithm, Computer Science Applications, Overdetermined system, GNSS applications, Position (vector), 11. Sustainability, 0502 economics and business, Automotive Engineering, Traitement du signal et de l'image, Sparse, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, Algorithm, Multipath propagation
Abstract

Multipath (MP) remains the main source of error when using global navigation satellite systems (GNSS) in a constrained environment, leading to biased measurements and thus to inaccurate estimated positions. This paper formulates the GNSS navigation problem as the resolution of an overdetermined system whose unknowns are the receiver position and speed, clock bias and clock drift, and the potential biases affecting GNSS measurements. We assume that only a part of the satellites are affected by MP, i.e., that the unknown bias vector has several zero components, which allows sparse estimation theory to be exploited. The natural way of enforcing this sparsity is to introduce an $\ell _{1}$ regularization associated with the bias vector. This leads to a least absolute shrinkage and selection operator problem that is solved using a reweighted- $\ell _{1}$ algorithm. The weighting matrix of this algorithm is designed carefully as functions of the satellite carrier-to-noise density ratio ( $C/N_{0}$ ) and the satellite elevations. Experimental validation conducted with real GPS data show the effectiveness of the proposed method as long as the sparsity assumption is respected.

Published
2019

30. Design and evaluation of braced touch for touchscreen input stabilisation

Author

Catherine Trask, Christine Gris, Damien Masson, Marcus Yung, Alix Goguey, Carl Gutwin, Philippe Palanque, Andy Cockburn, Airbus (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), University of Canterbury - UC (NEW ZEALAND), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), University of Saskatchewan (CANADA), and Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France)

Subjects
Computer science, Target selection, Human Factors and Ergonomics, Interface homme-machine, Vibration, Education, law.invention, Touchscreen, Architectures Matérielles, law, Génie logiciel, Selection (genetic algorithm), Simulation, General Engineering, Vehicles, Modélisation et simulation, Systèmes embarqués, Bracing, Cockpit, Turbulence, Human-Computer Interaction, Hardware and Architecture, Cryptographie et sécurité, Touch interaction, Aviation, Software
Abstract

Incorporating touchscreen interaction into cockpit flight systems offers several potential advantages to aircraft manufacturers, airlines, and pilots. However, vibration and turbulence are challenges to reliable interaction. We examine the design space for braced touch interaction, which allows users to mechanically stabilise selections by bracing multiple fingers on the touchscreen before completing selection. Our goal is to enable fast and accurate target selection during high levels of vibration, without impeding interaction performance when vibration is absent. Three variant methods of braced touch are evaluated, using doubletap, dwell, or a force threshold in combination with heuristic selection criteria to discriminate intentional selection from concurrent braced contacts. We carried out an experiment to test the performance of these methods in both abstract selection tasks and more realistic flight tasks. The study results confirm that bracing improves performance during vibration, and show that doubletap was the best of the tested methods.

Published
2019

31. Lexicographic R* Criterion For Decision Making Under Uncertainty in Reverse Logistics

Author

Zoé Krug, Olga Battaïa, Romain Guillaume, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), and Université Toulouse 1 Capitole - UT1 (FRANCE)

Subjects
0209 industrial biotechnology, Operations research, Computer science, Supply chain, 020208 electrical & electronic engineering, Uncertainty, Context (language use), 02 engineering and technology, Reverse logistics, Raw material, Lexicographical order, Facility location problem, 020901 industrial engineering & automation, Control and Systems Engineering, Order (business), 0202 electrical engineering, electronic engineering, information engineering, Decision-making, Recherche opérationnelle
Abstract

Reverse supply chains (RSC) deal with End-Of-Life products (EOL). They provide the benefits of reducing solid waste, creating new jobs, and generating income from the sales of re-manufactured products and savings in raw materials. At the same time, their design is more challenging in comparison with forward supply chains because of hardly predictable reverse flows of EOL products. Conventional approaches to address the uncertainty are usually risk-oriented and do not consider eventual opportunities. In order to overcome this drawback, we propose to use the R* criterion in the decision making process in a context of complete ignorance with a discrete set of equally possible scenarios. This criterion integrated in a new lexicographic algorithm is used in order to take the Decision-Maker’s (DM) behavior into account in different ways regarding if the uncertainty is considered as a risk or as an opportunity. Its performances are evaluated on the case study of facility location problem in reverse logistics.

Published
2019

32. Rationalizing the need of architecture-driven testing of interactive systems

Author

Canny, Alexandre, Bouzekri, Elodie, Martinie, Célia, Palanque, Philippe, Lárusdóttir, Marta Kristín, Winckler, Marco, Kuusinen, Kati, Bogdan, Cristian, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Eindhoven University of Technology - TU/e (NETHERLANDS), Interactive Critical Systems (IRIT-ICS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Eindhoven University of Technology [Eindhoven] (TU/e), Cristian Bogdan, Kati Kuusinen, Marta Kristín Lárusdóttir, Philippe Palanque, Marco Winckler, TC 13, WG 13.2, Systemic Change, and Institut National Polytechnique de Toulouse - INPT (FRANCE)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Computer science, System testing, 02 engineering and technology, [INFO.INFO-SE]Computer Science [cs]/Software Engineering [cs.SE], User input, Interface homme-machine, Field (computer science), Task (project management), [INFO.INFO-CR]Computer Science [cs]/Cryptography and Security [cs.CR], Software, Architectures Matérielles, Architecture-driven testing, 0202 electrical engineering, electronic engineering, information engineering, Génie logiciel, 0501 psychology and cognitive sciences, [INFO]Computer Science [cs], [INFO.INFO-HC]Computer Science [cs]/Human-Computer Interaction [cs.HC], Architecture, 050107 human factors, Interactive systems engineering, business.industry, Interactive system testing, 05 social sciences, 020207 software engineering, Modélisation et simulation, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Systèmes embarqués, Test (assessment), Cryptographie et sécurité, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, Software engineering, business
Abstract

Part 3: Task Modelling and Task-Based Approaches; International audience; Testing interactive systems is known to be a complex task that cannot be exhaustive. Indeed, the infinite number of combination of user input and the complexity of information presentation exceed the practical limits of exhaustive and analytical approach to testing [31]. Most interactive software testing techniques are produced by applying and tuning techniques from the field of software testing to try to address the specificities of interactive applications. When some elements cannot be taken into account by the software testing technique, they are usually ignored. In this paper we propose to follow an opposite approach, starting from a generic architecture for interactive systems (including both software and hardware elements) for identifying in a systematic way, testing problems and testing needs. This architecture-driven approach makes it possible to identify how software testing knowledge and techniques can support interactive systems testing but also where the interactive systems engineering community should invest in order to test their idiosyncrasies too.

Published
2019

33. Toward classroom experiences inclusive of students with disabilities

Author

Marcos Serrano, Christophe Jouffrais, Anja Thieme, Emeline Brulé, Oussama Metatla, Cynthia L. Bennett, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Telecom ParisTech (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), University of Bristol (UNITED KINGDOM), Microsoft (USA), University of Washington (USA), Institut Interdisciplinaire de l'Innovation - i3 (Palaiseau, France), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Télécom Paris (FRANCE), University of Bristol [Bristol], Microsoft Corporation [Redmond, Wash.], Institut interdisciplinaire de l’innovation (I3, une unité mixte de recherche CNRS (UMR 9217)), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Télécom ParisTech-MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), University of Washington [Seattle], Etude de L’Interaction Personne SystèmE (IRIT-ELIPSE), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Image & Pervasive Access Lab (IPAL), National University of Singapore (NUS)-MATHEMATIQUES, SCIENCES ET TECHNOLOGIES DE L'INFORMATION ET DE LA COMMUNICATION (UJF)-Agency for science, technology and research [Singapore] (A*STAR)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institute for Infocomm Research - I²R [Singapore], and Centre National de la Recherche Scientifique (CNRS)

Subjects
Digital content, Computer programming, 02 engineering and technology, Learning environments, [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], Assistive technology, ComputingMilieux_COMPUTERSANDEDUCATION, 0202 electrical engineering, electronic engineering, information engineering, Mathematics education, Educational content, 0501 psychology and cognitive sciences, 050107 human factors, business.industry, 4. Education, 05 social sciences, 020207 software engineering, Teaching assistant, Braille, Apprentissage, Human-Computer Interaction, Students with disabilities, Spatial learning, Psychology, business, Meaning (linguistics)
Abstract

International audience; More than ever, digital content and tools are being introduced and accepted in diverse educational contexts, offering opportunities for innovation and for making learning processes more encompassing, engaging, and collaborative. Multimodal tools fostering tactile, auditory, and spatial learning promise increased access for students with vision impairments (VI). Yet many existing popular classroom technologies, such as Scratch for learning computer programming, rely heavily on visual content and interactions. In practice, this means that students with VI continue to rely on screen readers, magnifiers, and braille displays to access and engage with educational materials, while also leveraging frequent support from a teaching assistant or the use of specialized tools. Although these are all important mechanisms to make educational content more accessible, they are inherently designed to be used by VI learners alone, often leaving the person isolated and excluded from learning activities with other students; meaning that accessible and assistive technology (AT) cannot alone foster connection among students with various abilities [1].In this article, we outline three areas of research and debate that we identified during the CHI 2018 workshop on the design of inclusive educational classroom technology for people with VI [2].

Published
2018

34. Remarks about the unification type of several non-symmetric non-transitive modal logics

Author

Philippe Balbiani, Institut National Polytechnique de Toulouse - INPT (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Logique, Interaction, Langue et Calcul (IRIT-LILaC), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, and Centre National de la Recherche Scientifique (CNRS)

Subjects
Pure mathematics, Types of modal logics, Unification, Logic, Normal modal logic, Existential quantification, Unification problem, 02 engineering and technology, Type (model theory), 01 natural sciences, Set (abstract data type), Normal modal logics, Non-symmetric modal logics, Computer Science::Logic in Computer Science, 0202 electrical engineering, electronic engineering, information engineering, 0101 mathematics, Mathematics, Logique en informatique, Transitive relation, 010102 general mathematics, Substitution (logic), [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], 16. Peace & justice, Non-transitive modal logics, TheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGES, Modal, 020201 artificial intelligence & image processing
Abstract

The problem of unification in a normal modal logic $L$ can be defined as follows: given a formula $\varphi$, determine whether there exists a substitution $\sigma$ such that $\sigma (\varphi )$ is in $L$. In this paper, we prove that for several non-symmetric non-transitive modal logics, there exists unifiable formulas that possess no minimal complete set of unifiers.

Published
2018

35. A scalable model based approach for data model evolution: Application to space missions data models

Author

Lynda Ait Oubelli, Béatrice Larzul, Judicaël Bedouet, Benoît Chausserie-Laprée, Romain Kervarc, Yamine Ait Ameur, Centre National d'Études Spatiales - CNES (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Office National d'Etudes et Recherches Aérospatiales - ONERA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), ONERA / DTIS, Université de Toulouse [Toulouse], ONERA-PRES Université de Toulouse, Assistance à la Certification d’Applications DIstribuées et Embarquées (IRIT-ACADIE), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Centre National d'Études Spatiales [Toulouse] (CNES), and Institut National Polytechnique de Toulouse - INPT (FRANCE)

Subjects
Computer Networks and Communications, Computer science, Data model evolution, Complex system, DATA MODEL COMPARISON, Context (language use), 02 engineering and technology, COMPOSITE EVOLUTION OPERATORS, Field (computer science), Data modeling, Data conservation, 020204 information systems, 0202 electrical engineering, electronic engineering, information engineering, Data model comparison, DATA MIGRATION, [INFO.INFO-DB]Computer Science [cs]/Databases [cs.DB], DATA MODEL EVOLUTION, 020207 software engineering, Modélisation et simulation, Data migration, Data science, Model driven engineering (MDE), MODEL DRIVEN ENGENEERING, Data model, Scalability, Composite evolution operators, Engineering design process, Software, DATA CONSERVATION
Abstract

International audience; During the development of a complex system, data models are the key to a successful engineering process, as they contain and organize all the information manipulated by the different functions involved in the design of the system. Moreover, these data models evolve throughout the design, as the development raises issues that have to be solved through a restructuration of data organization. But any such data model evolution has a deep impact on the functions that have already being defined.Recent research tries to deal with this issue by studying how complex industrial data models evolve from one version to another and how their data instances co-evolve. Complexity and scalability issues make this problem a major scientific challenge, leading to huge gains in development efficiency. This problem is of particular interest in the field of aeronautics and space systems. Indeed, the development of these systems produces many complex data models associated to the designed systems and/or to the systems under design, hence on the one hand data models are available. On the other hand, it is well known that these systems are developed in the context of collaborative projects that may last for decades. In such projects, specifications together with the associated data models are bound to evolve and engineering processes shall take into account this evolution.Our work addresses the problem of data model evolution in a model-driven engineering setting. We focus on minimizing the impact of model evolution on the system development processes in the specific context on the space engineering area, where data models may involve thousands of concepts and relationships, and we investigate the performance of the model-based development (MBD) approach we propose for data model evolution over two space missions, namely PHARAO and MICROSCOPE.

Published
2018

36. Passive mitigation for magnetic coupling between HV power line and aerial pipeline using PSO algorithms optimization

Author

Rabah Djekidel, Pierre Spiteri, Sid Ahmed Bessedik, Djillali Mahi, Université Amar Telidji - Laghouat, Traitement et Compréhension d’Images (IRIT-TCI), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Université Amar Telidji - Laghouat (ALGERIA), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)

Subjects
Particle Swarm Optimization (PSO), 020209 energy, Pipeline (computing), Energy Engineering and Power Technology, Faraday's law, 02 engineering and technology, Aerial pipelines, 7. Clean energy, Traitement des images, 0202 electrical engineering, electronic engineering, information engineering, Electrical and Electronic Engineering, Carson's formula, Physics, 020208 electrical & electronic engineering, Overhead power line, Particle swarm optimization, High voltage, Induced voltage, Inductive coupling, Electromagnetic induction, Power (physics), HV power line, [INFO.INFO-TI]Computer Science [cs]/Image Processing [eess.IV], Electromagnetic shielding, Algorithm
Abstract

International audience; This paper proposes a methodology based on Faraday's electromagnetic induction law (EMF) for evaluating the induced voltage produced by high voltage power line on an aerial metallic pipeline located parallel in its immediate vicinity under normal operating condition. It also describes the procedure of the induced voltage mitigation using the passive loop technique combined with the particle swarm optimization algorithm (PSO). The presence of a pipeline in the vicinity of an overhead power line strongly disturbs the mapping of the magnetic induction produced by this power line. The mitigation efficiency is significantly improved by optimizing the position of the loop conductors, by increasing the number of loops and the use of a shielding magnetic material of high relative permeability. The obtained simulation result is compared with that obtained by the Carson's formulas. A good agreement was obtained.

Published
2018

37. Constraints and changes: A survey of abstract argumentation dynamics

Author

Sylvie Doutre, Jean-Guy Mailly, Logique, Interaction, Langue et Calcul (IRIT-LILaC), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire d'Informatique Paris Descartes (LIPADE - EA 2517), Université Paris Descartes - Paris 5 (UPD5), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Université Paris Descartes - Paris V (FRANCE), Université Toulouse 1 Capitole (UT1)-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Institut National Polytechnique de Toulouse - INPT (FRANCE)

Subjects
Linguistics and Language, Knowledge representation and reasoning, Revision, Computer science, Semantics (computer science), Change, 0102 computer and information sciences, 02 engineering and technology, 01 natural sciences, Argumentation framework, Update, Argumentation theory, [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], Artificial Intelligence, Argument, 0202 electrical engineering, electronic engineering, information engineering, Set (psychology), Enforcement, Abstract Argumentation, 16. Peace & justice, Apprentissage, Computer Science Applications, Constraint (information theory), Computational Mathematics, 010201 computation theory & mathematics, 020201 artificial intelligence & image processing, Mathematical economics, Knowledge Representation and Reasoning
Abstract

International audience; This paper addresses the issue of the dynamic enforcement of a constraint in an argumentation system. The system consists in (1) an argumentation framework, made up, notably, of a set of arguments and of an attack relation, (2) an evaluation semantics, and (3) the evaluation result, computed from (1) and (2). An agent may want another agent to consider a new attack, or to have a given argument accepted, or even to relax the definition of the semantics. A constraint on any of the three components is thus defined, and it has to be enforced in the system. The enforcement may result in changes on components of the system. The paper surveys existing approaches for the dynamic enforcement of a constraint and its consequences, and reveals challenging enforcement cases that remain to be investigated.

Published
2018

38. On a unifying product form framework for redundancy models

Author

Ina Maria Verloop, Tejas Bodas, Urtzi Ayesta, Basque Foundation for Science ( Ikerbasque ), Institut de recherche en informatique de Toulouse ( IRIT ), Institut National Polytechnique [Toulouse] ( INP ) -Université Toulouse 1 Capitole ( UT1 ) -Université Toulouse - Jean Jaurès ( UT2J ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ), Équipe Services et Architectures pour Réseaux Avancés ( LAAS-SARA ), Laboratoire d'analyse et d'architecture des systèmes [Toulouse] ( LAAS ), Institut National Polytechnique [Toulouse] ( INP ) -Institut National des Sciences Appliquées - Toulouse ( INSA Toulouse ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut National Polytechnique [Toulouse] ( INP ) -Institut National des Sciences Appliquées - Toulouse ( INSA Toulouse ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National de la Recherche Scientifique ( CNRS ), Centre National de la Recherche Scientifique - CNRS (FRANCE), IKERBASQUE (SPAIN), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Universidad del País Vasco - Euskal Herriko Unibertsitatea - EHU (SPAIN), Laboratoire d'Analyse et d'Architecture des Systèmes - LAAS (Toulouse, France), Ikerbasque - Basque Foundation for Science, Réseaux, Mobiles, Embarqués, Sans fil, Satellites (IRIT-RMESS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Toulouse Mind & Brain Institut (TMBI), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Centre National de la Recherche Scientifique (CNRS), Équipe Services et Architectures pour Réseaux Avancés (LAAS-SARA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Basque Foundation for Science (Ikerbasque), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1)

Subjects
Exponential distribution, Redundancy-d, Computer science, Computer Networks and Communications, Generalization, Système d'exploitation, 0211 other engineering and technologies, Réseaux et télécommunications, 02 engineering and technology, 01 natural sciences, Combinatorics, 010104 statistics & probability, Redundancy (information theory), Architectures Matérielles, Server, Cancel-on-start, 0202 electrical engineering, electronic engineering, information engineering, Redundancy (engineering), 0101 mathematics, Queue, [ INFO.INFO-RO ] Computer Science [cs]/Operations Research [cs.RO], Mathematics, 020203 distributed computing, 021103 operations research, Stationary distribution, business.industry, Product-form distribution, [INFO.INFO-RO]Computer Science [cs]/Operations Research [cs.RO], Queueing system, Systèmes embarqués, [ INFO.INFO-PF ] Computer Science [cs]/Performance [cs.PF], [MATH.MATH-PR]Mathematics [math]/Probability [math.PR], [INFO.INFO-PF]Computer Science [cs]/Performance [cs.PF], Hardware and Architecture, Independence assumption, Modeling and Simulation, Product (mathematics), Closed-form expression, business, [ MATH.MATH-PR ] Mathematics [math]/Probability [math.PR], Software, Computer network
Abstract

In this paper, we present a unifying analysis for redundancy systems with cancel-on-start ( c . o . s . ) and cancel-on-complete ( c . o . c . ) with exponentially distributed service requirements. With c . o . s . ( c . o . c . ) all redundant copies are removed as soon as one of the copies starts (completes) service. As a consequence, c . o . s . does not waste any computing resources, as opposed to c . o . c . We show that the c . o . s . model is equivalent to a queueing system with multi-type jobs and servers, which was analyzed in Visschers et al., (2012), and show that c . o . c . (under the assumption of i.i.d. copies) can be analyzed by a generalization of Visschers et al., (2012) where state-dependent departure rates are permitted. This allows us to show that the stationary distribution for both the c . o . c . and c . o . s . models has a product form. We give a detailed first-time analysis for c . o . s and derive a closed form expression for important metrics like mean number of jobs in the system, and probability of waiting. We also note that the c . o . s . model is equivalent to Join-Shortest-Work queue with power of d (JSW( d )). In the latter, an incoming job is dispatched to the server with smallest workload among d randomly chosen ones. Thus, all our results apply mutatis-mutandis to JSW( d ). Comparing the performance of c . o . s . with that of c . o . c . with i.i.d. copies gives the unexpected conclusion (since c . o . s . does not waste any resources) that c . o . s . is worse in terms of mean number of jobs. As part of ancillary results, we illustrate that this is primarily due to the assumption of i.i.d. copies in case of c . o . c . (together with exponentially distributed requirements) and that such assumptions might lead to conclusions that are qualitatively different from that observed in practice.

Published
2018

39. Profile reliability to improve recommendation in social-learning context

Author

Ikram Amous, Manel Mezghanni, Corinne Amel Zayani, Leila Ghorbel, Florence Sèdes, André Péninou, Multimedia, InfoRmation systems and Advanced Computing Laboratory (MIRACL), Faculté des Sciences Economiques et de Gestion de Sfax (FSEG Sfax), Université de Sfax - University of Sfax-Université de Sfax - University of Sfax, Systèmes d’Informations Généralisées (IRIT-SIG), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse - Jean Jaurès (UT2J), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and Institut National Polytechnique de Toulouse - INPT (FRANCE)

Subjects
Computer science, media_common.quotation_subject, Context (language use), 02 engineering and technology, Library and Information Sciences, Recommender system, Semantic similarity, 020204 information systems, Conflict resolution, 0202 electrical engineering, electronic engineering, information engineering, Quality (business), Interests, K-means, Reliability (statistics), media_common, Information retrieval, Social network, business.industry, Temperature, Recherche d'information, Reliability, Social learning, Computer Science Applications, Enrichment, [INFO.INFO-IR]Computer Science [cs]/Information Retrieval [cs.IR], 020201 artificial intelligence & image processing, business, Information Systems
Abstract

Purpose Generally, the user requires customized information reflecting his/her current needs and interests that are stored in his/her profile. There are many sources which may provide beneficial information to enrich the user’s interests such as his/her social network for recommendation purposes. The proposed approach rests basically on predicting the reliability of the users’ profiles which may contain conflictual interests. The paper aims to discuss this issue. Design/methodology/approach This approach handles conflicts by detecting the reliability of neighbors’ profiles of a user. The authors consider that these profiles are dependent on one another as they may contain interests that are enriched from non-reliable profiles. The dependency relationship is determined between profiles, each of which contains interests that are structured based on k-means algorithm. This structure takes into consideration not only the evolutionary aspect of interests but also their semantic relationships. Findings The proposed approach was validated in a social-learning context as evaluations were conducted on learners who are members of Moodle e-learning system and Delicious social network. The quality of the created interest structure is assessed. Then, the result of the profile reliability is evaluated. The obtained results are satisfactory. These results could promote recommendation systems as the selection of interests that are considered of enrichment depends on the reliability of the profiles where they are stored. Research limitations/implications Some specific limitations are recorded. As the quality of the created interest structure would evolve in order to improve the profile reliability result. In addition, as Delicious is used as a main data source for the learner’s interest enrichment, it was necessary to obtain interests from other sources, such as e-recruitement systems. Originality/value This research is among the pioneer papers to combine the semantic as well as the hierarchical structure of interests and conflict resolution based on a profile reliability approach.

Published
2018

40. DV-Hop Localization With Protocol Sequence Based Access

Author

Feng Shu, Huang Xinyu, Fu Xiao, Wei Jun, Yijin Zhang, Linqing Gui, Thierry Val, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Nanjing University of Science and Technology - NUST (CHINA), Nanjing University of Posts and Telecommunications - NJUPT (CHINA), Southeast University - SEU (CHINA), National Mobile Communications Research Laboratory - NCRL (Nanjing, Chine), Institut National Polytechnique de Toulouse - INPT (FRANCE), Nanjing University of Information Science and Technology (NUIST), Nanjing University of Posts and Telecommunications, National Mobile Communications Research Laboratory [Jiangsu], Southeast University [Jiangsu], Réseaux, Mobiles, Embarqués, Sans fil, Satellites (IRIT-RMESS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, and Université Toulouse - Jean Jaurès (UT2J)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], Protocol sequence, Computer Networks and Communications, Computer science, Système d'exploitation, Time division multiple access, Réseaux et télécommunications, Aerospace Engineering, Access control, 02 engineering and technology, Broadcasting, Distance Vector Hop (DV-Hop), Hop (networking), [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], 0203 mechanical engineering, Architectures Matérielles, Computer Science::Networking and Internet Architecture, 0202 electrical engineering, electronic engineering, information engineering, Electrical and Electronic Engineering, business.industry, Network packet, ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS, 020302 automobile design & engineering, 020206 networking & telecommunications, Systèmes embarqués, Range-free, Localization, Automotive Engineering, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, [INFO.INFO-OS]Computer Science [cs]/Operating Systems [cs.OS], business, Wireless sensor network, Computer network
Abstract

International audience; Among typical range-free localization schemes for sensor networks, DV-Hop has its distinguishing advantage of the capability to localize unknown nodes, which have less than three or even no neighbor anchors. However, existing DV-Hop based localization methods have not considered the problem of packet collisions, which can frequently happen during the throughout-whole-network broadcast of numerous data packets at the first two steps of DV-Hop. In order to effectively improve the success rate of packet transmission between nodes, this paper proposes a medium access control (MAC) method based on Chinese Remainder Theorem (CRT) protocol sequence for DV-Hop localization. First, a broadcasting strategy is designed for the proposed MAC method. Then, dedicated procedures for both anchor nodes and unknown nodes are presented to implement the designed MAC method in DV-Hop localization. Through simulation and evaluation, the performance of DV-Hop localization with the proposed MAC method is thoroughly investigated. Simulation results show that when the number of protocol sequences is larger than a certain number, the proposed MAC method can provide DV-Hop with better localization accuracy than E-CSMA/CA, while keeping similar localization time.

Published
2018

41. Unmixing dynamic PET images with variable specific binding kinetics

Author

Thomas Oberlin, Nicolas Dobigeon, Yanna Cruz Cavalcanti, Maria Joao Ribeiro, Simon Stute, Clovis Tauber, Commissariat à l'Energie Atomique et aux énergies alternatives - CEA (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Institut National de la Santé et de la Recherche Médicale - INSERM (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Université de Tours (FRANCE), Université Paris-Sud 11 (FRANCE), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)

Subjects
FOS: Computer and information sciences, Computer science, Computer Vision and Pattern Recognition (cs.CV), Computer Science - Computer Vision and Pattern Recognition, FOS: Physical sciences, Brain imaging, Health Informatics, 030218 nuclear medicine & medical imaging, Non-negative matrix factorization, Matrix decomposition, Methodology (stat.ME), Traitement des images, 03 medical and health sciences, Imaging, Three-Dimensional, 0302 clinical medicine, Factorization, Component (UML), Image Interpretation, Computer-Assisted, Humans, Radiology, Nuclear Medicine and imaging, NMF, Dynamic PET image, Statistics - Methodology, Brain Mapping, Radiological and Ultrasound Technology, Phantoms, Imaging, Matrix factorization, Hyperspectral imaging, Unmixing, Computer Graphics and Computer-Aided Design, Independent component analysis, Nonlinear system, Positron-Emission Tomography, Physics - Data Analysis, Statistics and Probability, Principal component analysis, Computer Vision and Pattern Recognition, Radiopharmaceuticals, Factor analysis, Factor Analysis, Statistical, Biological system, Algorithms, Data Analysis, Statistics and Probability (physics.data-an), 030217 neurology & neurosurgery
Abstract

To analyze dynamic positron emission tomography (PET) images, various generic multivariate data analysis techniques have been considered in the literature, such as principal component analysis (PCA), independent component analysis (ICA), factor analysis and nonnegative matrix factorization (NMF). Nevertheless, these conventional approaches neglect any possible nonlinear variations in the time activity curves describing the kinetic behavior of tissues with specific binding, which limits their ability to recover a reliable, understandable and interpretable description of the data. This paper proposes an alternative analysis paradigm that accounts for spatial fluctuations in the exchange rate of the tracer between a free compartment and a specifically bound ligand compartment. The method relies on the concept of linear unmixing, usually applied on the hyperspectral domain, which combines NMF with a sum-to-one constraint that ensures an exhaustive description of the mixtures. The spatial variability of the signature corresponding to the specific binding tissue is explicitly modeled through a perturbed component. The performance of the method is assessed on both synthetic and real data and is shown to compete favorably when compared to other conventional analysis methods. The proposed method improved both factor estimation and proportions extraction for specific binding. Modeling the variability of the specific binding factor has a strong potential impact for dynamic PET image analysis.

Published
2018

42. Predicting information diffusion on Twitter – Analysis of predictive features

Author

Thi Bich Ngoc Hoang, Josiane Mothe, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), University of Economics – The University of Danang (VIETNAM), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)

Subjects
Information propagation, Diffusion (acoustics), General Computer Science, Computer science, Control (management), Fact checking, Tweet propagation, 02 engineering and technology, computer.software_genre, Predicting information propagation, Theoretical Computer Science, 020204 information systems, 0202 electrical engineering, electronic engineering, information engineering, Information diffusion, H- INFORMATIQUE, Théorie de l'information, Social network, business.industry, Recherche d'information, Order (business), Modeling and Simulation, Microblogs, 020201 artificial intelligence & image processing, Data mining, State (computer science), business, computer
Abstract

Information propagation on online social network focuses much attention in various domains as varied as politics, fact checking, or marketing. Modeling information diffusion in such growing communication media is crucial in order both to understand information propagation and to better control it. Our research aims at predicting whether a post is going to be forwarded or not. Moreover, we aim at predicting how much it is going to be diffused. Our model is based on three types of features: user-based, time-based and content-based. Using three collections corresponding to a total of about 16 millions of tweets, we show that our model improves of about 5% F-measure compared to the state of the art, both when predicting if a tweet is going to be re-tweeted and when predicting how popular it will be. F-measure in our model is between 70% and 82%, depending on the collection. We also show that some features we introduced are very important to predict retweetability such as the numbers of followers and number of communities that a user belongs to. Our contribution in this paper is twofold: firstly we defined new features to represent tweets in order to predict their possible propagation; secondly we evaluate the model we built on top of both features from the literature and features we defined on three collections and show the usefulness of our features in the prediction.

Published
2018

43. Modeling, classifying and generating large-scale Google-like workload

Author

Ines de Courchelle, Georges Da Costa, Léo Grange, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Système d’exploitation, systèmes répartis, de l’intergiciel à l’architecture (IRIT-SEPIA), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse III - Paul Sabatier (UT3), Équipe Services et Architectures pour Réseaux Avancés (LAAS-SARA), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Toulouse Mind & Brain Institut (TMBI), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), and Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J)

Subjects
[INFO.INFO-AR]Computer Science [cs]/Hardware Architecture [cs.AR], General Computer Science, Computer science, Système d'exploitation, Réseaux et télécommunications, 02 engineering and technology, computer.software_genre, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], Architectures Matérielles, Schema (psychology), 0202 electrical engineering, electronic engineering, information engineering, Electrical and Electronic Engineering, Reference implementation, Workload generation, Workload analysis, Large scale, 020206 networking & telecommunications, Workload, Classification, Google dataset, Systèmes embarqués, Reproducible experiments, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, 020201 artificial intelligence & image processing, [INFO.INFO-OS]Computer Science [cs]/Operating Systems [cs.OS], Data mining, computer
Abstract

International audience; One of the key elements needed to test most large-scale scheduling algorithms is a testing infrastructure. Large scale is of upmost importance as failures and complex behaviors are common occurrences only at such scale. In order to test the reaction of a system to failures or extreme behaviors, it is necessary to be able to create large scale environments. Such an infrastructure must be reproducible so that several studies are able to compare themselves but also capable of diversity as otherwise it would risk to limit them to particular subcases. In this article, we propose a generic adaptable and reusable model of large scale workload. The original schema comes from the Google Cluster Workload Traces which is a perfect representative of large scale production workload. The methodology to produce the model can be used at different precision levels and can classify the input level without human supervision. Contrary to most model analysis of such traces, we propose along with our model a reference implementation in order for other studies using our results to produce comparable experiments.

Published
2018

44. Possibilistic preference networks

Author

Henri Prade, Didier Dubois, Héla Gouider, Nahla Ben Amor, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Université de Tunis (TUNISIA), Laboratoire de Recherche Opérationnelle de Décision et de Contrôle de Processus (LARODEC), Université de Tunis-ISG de Tunis, Argumentation, Décision, Raisonnement, Incertitude et Apprentissage (IRIT-ADRIA), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Centre National de la Recherche Scientifique (CNRS), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)

Subjects
Mathematical optimization, Information Systems and Management, Ceteris paribus, 02 engineering and technology, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], Theoretical Computer Science, Set (abstract data type), Preference modeling, Artificial Intelligence, 020204 information systems, 0202 electrical engineering, electronic engineering, information engineering, Graphical model, Preference (economics), Possibility theory, Mathematics, Intelligence artificielle, Decision problem, 16. Peace & justice, Computer Science Applications, Control and Systems Engineering, Product (mathematics), 020201 artificial intelligence & image processing, Graphical models, Partially ordered set, Software, Pareto ordering
Abstract

International audience; This paper studies the use of product-based possibilistic networks for representing preferences in multidimensional decision problems. This approach uses symbolic possibility weights and defines a partial preference order among solutions to a set of conditional preference statements on the domains of discrete decision variables. In the case of Boolean decision variables, this partial ordering is shown to be consistent with the preference ordering induced by the ceteris paribus assumption adopted in CP-nets. Namely, by completing the possibilistic net ordering with suitable constraints between products of symbolic weights, all CP-net preferences can be recovered. Computing procedures for comparing solutions are provided. The flexibility and representational power of the approach is stressed.

Published
2018

45. Using smart offices to predict occupational stress

Author

Ane Alberdi, Adrian Basarab, Asier Aztiria, Diane J. Cook, Mondragon Unibertsitatea, CoMputational imagINg anD viSion (IRIT-MINDS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Université Toulouse III - Paul Sabatier (UT3), Washington State University (WSU), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - INPT (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Mondragon Unibertsitatea (SPAIN), University of Washington (USA), Washington State University - WSU (USA), Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France), and Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, Smart office, Physiology, Computer science, Applied psychology, Human Factors and Ergonomics, 02 engineering and technology, Stress, Interface homme-machine, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], Task (project management), 020204 information systems, 0202 electrical engineering, electronic engineering, information engineering, [INFO.INFO-HC]Computer Science [cs]/Human-Computer Interaction [cs.HC], Behavior, Public Health, Environmental and Occupational Health, Behavioral pattern, Workload, Intelligence artificielle, Automatic assessment, Mental health, Turnover, 8. Economic growth, Presenteeism, Absenteeism, 020201 artificial intelligence & image processing, Occupational stress
Abstract

International audience; Occupational stress is increasingly present in our society. Usually, it is detected too late, resulting in physical and mental health problems for the worker, as well as economic losses for the companies due to the consequent absenteeism, presenteeism, reduced motivation or staff turnover. Therefore, the development of early stress detection systems that allow individuals to take timely action and prevent irreversible damage is required. To address this need, we investigate a method to analyze changes in physiological and behavioral patterns using unobtrusively and ubiquitously gathered smart office data. The goal of this paper is to build models that predict self-assessed stress and mental workload scores, as well as models that predict workload conditions based on physiological and behavior data. Regression models were built for the prediction of the self-reported stress and mental workload scores from data based on real office work settings. Similarly, classification models were employed to detect workload conditions and change in these conditions. Specific algorithms to deal with class-imbalance (SMOTEBoost and RUSBoost) were also tested. Results confirm the predictability of behavioral changes for stress and mental workload levels, as well as for change in workload conditions. Results also suggest that computer-use patterns together with body posture and movements are the best predictors for this purpose. Moreover, the importance of self-reported scores' standardization and the suitability of the NASA Task Load Index test for workload assessment is noticed. This work contributes significantly towards the development of an unobtrusive and ubiquitous early stress detection system in smart office environments, whose implementation in the industrial environment would make a great beneficial impact on workers’ health status and on the economy of companies.

Published
2018

46. Hypersphere fitting from noisy data using an EM algorithm

Author

Barbara Pilastre, Julien Lesouple, Yoann Altmann, Jean-Yves Tourneret, Télécommunications Spatiales et Aéronautiques - Telecommunications for Space ant Aeronautics (TéSA), Laboratoire de recherche coopératif dans les télécommunications spatiales et aéronautiques (TESA), Heriot-Watt University [Edinburgh] (HWU), CoMputational imagINg anD viSion (IRIT-MINDS), Institut de recherche en informatique de Toulouse (IRIT), Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut National Polytechnique (Toulouse) (Toulouse INP), Royal Academy of Engineering under the Research Fellowship scheme RF201617/16/31, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Heriot-Watt University (UNITED KINGDOM), Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (FRANCE), and Institut de Recherche en Informatique de Toulouse - IRIT (Toulouse, France)

Subjects
Noise measurement, Applied Mathematics, Hypersphere fitting, 020206 networking & telecommunications, Statistical model, 02 engineering and technology, Hypersphere, Expected value, Maximum likelihood estimation, Expectation-maximization algorithm, von Mises-Fisher distribution, Distribution (mathematics), [INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, Signal Processing, Expectation–maximization algorithm, 0202 electrical engineering, electronic engineering, information engineering, A priori and a posteriori, Traitement du signal et de l'image, Electrical and Electronic Engineering, Von Mises–Fisher distribution, Algorithm, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, Mathematics
Abstract

International audience; This letter studies a new expectation maximization (EM) algorithm to solve the problem of circle, sphere and more generally hypersphere fitting. This algorithm relies on the introduction of random latent vectors having a priori independent von Mises-Fisher distributions defined on the hypersphere. This statistical model leads to a complete data likelihood whose expected value, conditioned on the observed data, has a Von Mises-Fisher distribution. As a result, the inference problem can be solved with a simple EM algorithm. The performance of the resulting hypersphere fitting algorithm is evaluated for circle and sphere fitting.

Published
2021

47. Clusters of Defects as a Possible Origin of Random Telegraph Signal in Imager Devices: a DFT based Study

Author

L. Martin Samos, Nicolas Richard, P.L. Julliard, Denis Rideau, Anne Hémeryck, A. LeRoch, Vincent Goiffon, Filadelfo Cristiano, Antoine Jay, S. de Gironcoli, Commissariat à l'Energie Atomique et aux énergies alternatives - CEA (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), STMicroelectronics (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), CNR Istituto Officina dei Materiali - IOM (Rome, Italy), Équipe Modélisation Multi-niveaux des Matériaux (LAAS-M3), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Équipe Matériaux et Procédés pour la Nanoélectronique (LAAS-MPN), STMicroelectronics [Crolles] (ST-CROLLES), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), CNR Istituto Officina dei Materiali (IOM), Consiglio Nazionale delle Ricerche [Roma] (CNR), Scuola Internazionale Superiore di Studi Avanzati / International School for Advanced Studies (SISSA / ISAS), European Project: 871813,H2020-EU.2.1.1. - INDUSTRIAL LEADERSHIP - Leadership in enabling and industrial technologies - Information and Communication Technologies (ICT) ,MUNDFAB (2020), Centre d'Études de Limeil-Valenton (CEA-DAM), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), and National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)

Subjects
Band gap, Radiation effects, 02 engineering and technology, 01 natural sciences, Signal, Settore FIS/03 - Fisica della Materia, Atomic measurements, Metastability, 0103 physical sciences, cross sections, Cluster (physics), Traitement du signal et de l'image, Electronics, defects, 010302 applied physics, Physics, [PHYS]Physics [physics], Modulation, Semiconductor device measurement, business.industry, defects electronic states, Time measurement, 021001 nanoscience & nanotechnology, Discrete Fourier transforms, Computational physics, Semiconductor, Dark current, random telegraph signal, (SISPAD)(SISPAD)Dark current, 0210 nano-technology, business, electronic states, Switches
Abstract

International audience; The origin of the random telegraph signal (RTS) observed in semiconductors-based electronic devices is still subject to debates. In this work, by means of atomistic simulations, typical clusters of defects as could be obtained after irradiation or implantation are studied as a possible cause for RTS. It is shown that: (i) a cluster of defects is highly metastable, (ii) it introduces several electronic states in the band gap, (iii) it has an electronic cross section much higher than the one of point defects. These three points can simultaneously explain why an electronhole generation rate can switch with time, while respecting the experimental measurement.

Published
2021

48. On the Impact of Intrinsic Delay Variation Sources on Iridium LEO Constellation

Author

Nicolas Kuhn, Jean-Baptiste Dupe, Emmanuel Chaput, Cedric Baudoin, Amal Boubaker, Renaud Sallantin, Andre-Luc Beylot, Centre National d'Études Spatiales - CNES (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Thales (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (FRANCE), and Laboratoire de recherche en télécommunications spatiales et aéronautiques - TéSA (Toulouse, France)

Subjects
CUBIC TCP, Physics, business.industry, Iridium satellite constellation, chemistry.chemical_element, Iridium constellation, Autre, Low earth orbit, chemistry, Satellite constellations, CUBIC TCP Handovers, Satellite, Astrophysics::Earth and Planetary Astrophysics, Iridium, Aerospace engineering, business, Variation (astronomy), Computer Science::Information Theory, Constellation, Medium Earth orbit
Abstract

The recent decades have seen an increasing interest in Medium Earth Orbit and Low Earth Orbit satellite constellations. However, there is little information on the delay variation characteristics of these systems and the resulting impact on high layer protocols. To fill this gap, this paper simulates a constellation that exhibits the same delay characteristics as the already deployed Iridium but considers closer bandwidths to constellation projects’. We identify five major sources of delay variation in polar satellite constellations with different occurrence rates: elevation, intra-orbital handover, inter-orbital handover, orbital seam handover and Inter-Satellite Link changes. We simulate file transfers of different sizes to assess the impact of each of these delay variations on the file transfer. We conclude that the orbital seam is the less frequent source of delay and induces a larger impact on a small file transfers: the orbital seam, which occurs at most three times during 24 h, induces a 66% increase of the time needed to transmit a small file. Inter-orbital and intra-orbital handovers occur less often and reduce the throughput by approximately ∼ 8% for both low and high throughput configurations. The other sources of delay variations have a negligible impact on small file transfers, and long file transfers are not impacted much by the delay variations.

Published
2021

49. Enhancing Engineering Project Management Through Process Alignment

Author

Rui Xue, Rob A. Vingerhoeds, Claude Baron, Philippe Esteban, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), Beijing University of Technology - BJUT (CHINA), Laboratoire d'Analyse et d'Architecture des Systèmes - LAAS (Toulouse, France), Département d'Ingénierie des Systèmes Complexes - DISC (Toulouse, France), Beijing University of Technology, Équipe Ingénierie Système et Intégration (LAAS-ISI), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Laboratoire QUARTZ (QUARTZ ), Université Paris 8 Vincennes-Saint-Denis (UP8)-SUPMECA - Institut supérieur de mécanique de Paris (SUPMECA)-Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-Ecole Internationale des Sciences du Traitement de l'Information (EISTI), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), and Université Paris 8 Vincennes-Saint-Denis (UP8)-Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA)-SUPMECA - Institut supérieur de mécanique de Paris (SUPMECA)-Ecole Internationale des Sciences du Traitement de l'Information (EISTI)

Subjects
Process management, Computer science, Process Integration, Systems Engineering, 0211 other engineering and technologies, 02 engineering and technology, [INFO.INFO-SE]Computer Science [cs]/Software Engineering [cs.SE], Standard Alignment, Lead (geology), Autre, 021105 building & construction, 0502 economics and business, Process integration, Project management, Process alignment, business.industry, 05 social sciences, [INFO.INFO-CE]Computer Science [cs]/Computational Engineering, Finance, and Science [cs.CE], General Engineering, Project Management, [INFO.INFO-IA]Computer Science [cs]/Computer Aided Engineering, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, [INFO.INFO-PF]Computer Science [cs]/Performance [cs.PF], Order (business), business, 050203 business & management
Abstract

International audience; In order to lead successful projects, coordinating the different business units of a company is compulsory. This paper proposes a framework to make companies’ practices evolve toward a better alignment of the business units based on their processes, and illustrates it with project management and systems engineering processes. Indeed, all the different organization units intend to serve the common global objective to satisfy the customer needs, and need to closely collaborate during projects. However, work organization in companies often leads to barriers between these stakeholders, with the result of an incoherent decision-making that may compromise project execution. Therefore, the issue of processes alignment from different domains lies at the very heart of ongoing research topics and ranks first among economic and industrial concerns. This paper uses a qualitative approach to show how different business units’ processes can be integrated and illustrate this framework by aligning the systems engineering and project management processes within a certain engineering project context. By using the proposed framework, different teams (or even different companies, in a context of distributed enterprise) can align their practices, while also making them evolve toward a better compliance with standards.

Published
2021

50. Can Proactive Obsolescence Management and Innovation go hand in hand during the Conceptual Design Phase of Complex Systems?

Author

Salas Cordero, Sophia Karolina, Vingerhoeds, Rob A., Baron, Claude, Zolghadri, Marc, Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), and ISAE-Supméca – Institut supérieur de mécanique de Paris (FRANCE)

Subjects
Risk, Autre, Obsolescence, Conceptual Design, Systems Engineering, Innovation
Abstract

Innovation is a vital element in the dynamic world we live in, aiming at add-ing value to developing new systems. Obsolescence on the other hand com-prehends the deterioration of the system or component capacity to operate when it is no longer suitable to fulfil the required function, even if it still operates and can be manufactured and supported. As innovative and obsolete products can be seen as opposites, the proactive management of obsoles-cence encompasses the principles of innovation. Obsolescence has so far been mainly addressed from a reactive point of view. Realizing the impact of the conceptual design phase on a system’s life-cycle cost, this paper presents how a model-based system engineering approach, proactively assessing obso-lescence risks, leverages with innovation considerations. In doing so, the pa-per builds on technology readiness levels (TRL) to identify critical compo-nents and innovation considerations. With clearly identified risks, designers can knowingly decide whether to improve a design, by making it robust and resilient, or to accept the risks and develop an obsolescence management plan. The paper is illustrated with an example from the automotive industry.

Published
2021

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