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International audience; The textile and clothing industry is the first manufacture sector in Tunisia in terms of employment and number of enterprises. It generates large volumes of textile dyeing wastewater (TDWW) containing high concentrations of saline, alkaline, and recalcitrant pollutants that could fuel tenacious and resilient electrochemically active microorganisms in bioanodes of bioelectrochemical systems. In this study, a designed hybrid bacterial halothermotolerant bioanode incorporating indigenous and exogenous bacteria from both hypersaline sediment of Chott El Djerid (HSCE) and TDWW is proposed for simultaneous treatment of real TDWW and anodic current generation under high salinity. For the proposed halothermotolerant bioanodes, electrical current production, chemical oxygen demand (COD) removal efficiency, and bacterial community dynamics were monitored. All the experiments of halothermotolerant bioanode formation have been conducted on 6 cm2 carbon felt electrodes polarized at −0.1 V/SCE and inoculated with 80% of TDWW and 20% of HSCE for 17 days at 45°C. A reproducible current production of about 12.5 ± 0.2 A/m2 and a total of 91 ± 3% of COD removal efficiency were experimentally validated. Metagenomic analysis demonstrated significant differences in bacterial diversity mainly at species level between anodic biofilms incorporating allochthonous and autochthonous bacteria and anodic biofilm containing only autochthonous bacteria as a control. Therefore, we concluded that these results provide for the first time a new noteworthy alternative for achieving treatment and recover energy, in the form of a high electric current, from real saline TDWW.

International audience; Nous proposons une nouvelle approche d’agrégation pour l’estimation de la pertinence multidimensionnelle. L’approche est basée sur un opérateur d’agrégation mathématique qui utilise une mesure floue permettant la quantification de l’importance estimée des critères ainsi que leur degré d’interaction ou d’interdépendance. Nous évaluons l’opérateur proposé dans le cadre de trois scénarios de recherche d’information, en l’occurrence une tâche de recherche de tweets, une tâche de recherche personnalisée dans les folksonomies et une tâche de recherche d’information contextuelle. Les résultats expérimentaux obtenus montrent l’impact de l’approche proposée sur les performances de recherche.

International audience; Evaporation of a saline solution from a porous medium often leads to the precipitation of salt at the surface of the porous medium. It is commonly observed that the crystallized salt does not form everywhere at the porous medium surface but at some specific locations. This is interpreted at the signature of spatial variations in the salt concentration at the surface of the porous medium prior to the onset of crystallization. We explore numerically the link between the ion concentration spatial variations at the surface and porous medium heterogeneities considering strongly anisotropic short-range correlated permeability Gaussian fields corresponding to a vertical layering perpendicular to the top evaporative surface for the case of the evaporation–wicking situation. It is shown that the ion concentration extrema at the surfaces correspond to stagnation points with minima corresponding to divergent stagnation points and maxima to convergent stagnation points. Counter-intuitively, the ion concentration maxima are shown to correspond to permeability minima. However, the ion concentration absolute maximum does not necessarily always correspond to the permeability absolute minimum. More generally, the study emphasizes the key role played by the impact of heterogeneities on the velocity field induced in the medium by the evaporation process. It is also shown that the number of ion mass fraction maxima at the porous medium surface is generally much lower than the naive prediction based on the number of correlation lengths spanning the medium.

Coastal lagoon sediments are important for the biogeochemical carbon cycle at the land-ocean transition, as they form hotspots for organic carbon burial, as well as potential sites for authigenic carbonate formation. Here, we employ an early diagenetic model to quantify the coupled redox cycling of carbon, iron and sulphur in the sediments of the shallow Ghar El Melh (GEM) lagoon (Tunisia). The model simulated depth profiles show a good correspondence with available pore water data (dissolved inorganic carbon, NH 4 + , total alkalinity, Ca 2+ , Fe 2+ and SO 4 2− ) and solid phase data (organic matter, pyrite, calcium carbonate and iron (oxyhydr)oxides). This indicates that the model is able to capture the dominant processes influencing the sedimentary biogeochemical cycling. Our results show that sediment of the GEM lagoon is an efficient reactor for organic matter breakdown (burial efficiency < 10%), with an important role for aerobic respiration (32%) and sulphate reduction (61%). Despite high rates of sulphate reduction, free sulphide does not accumulate in the pore water, due to a large terrestrial input of reactive iron oxides and the efficient sequestration of free sulphide into iron sulphide phases. High pyrite burial (2.2 mmol FeS 2 m −2 d −1 ) prevents the reoxidation of reduced sulphide, thus resulting in a low total oxygen uptake (4.7 mmol m −2 d −1 ) of the sediment and a relatively high oxygen penetration depth. The formation of pyrite also generates high amounts of alkalinity in the pore water, which stimulates authigenic carbonate precipitation (2.7 mmol m −2 d −1 ) and leads to alkalinity release to the overlying water (3.4 mmol m −2 d −1 ). Model simulations with and without an N-cycle reveal a limited influence of nitrification and denitrification on overall organic matter diagenesis. Overall, our study highlights the potential role of coastal lagoons for the global carbon and sulphur cycle, and their possible contribution to shelf alkalinity, which increases the buffering capacity of the coastal ocean for CO 2 uptake.

International audience; This paper deals with the comparison of robust control approaches for the level water control of coupled tanks system. A new ultra-local model control (ULMC) approach leading to adaptive controller is proposed. The parameter identification of the ultra-local model is based on the algebraic derivation techniques. The main advantages of this control strategy are its simplicity and robustness. A comparison study with the integral sliding mode control (ISMC) approach is carried out. The perfect knowledge of the output variable degree, which is a standard assumption for sliding modes, is assumed here. The comparison of the simulation results for the proposed adaptive controller with the ISMC controller and the classical PID controller has a better performances in the presence of external perturbations and parameter uncertainties.

International audience; In this paper, a four-phase approach for Integrated Procurement-Production (IPP) tactical planning in a multiechelon, multi-product and multi-period Supply Chain (SC) network is proposed. To account for ambiguity and vagueness in some real-world data and preferences, in the first phase of the approach, the Fuzzy Technique for Order Preference by Similarity to Ideal Solution (fuzzy TOPSIS) method is used to obtain the overall performance and risk ratings of the suppliers with regard to a set of qualitative and quantitative criteria. In the second phase, we introduce a novel multi-objective possibilistic mixed integer linear programming model (MOPMILP) for solving an IPP planning considering conflicting goals simultaneously: maximization of the overall performance and minimization of the overall risk. Then, after converting this MOPMILP model into an equivalent crisp multi-objective mixed integer linear programming (MOMILP) model, we use the Goal Programming(GP) approach to solve this MOMILP model in order to find an efficient compromise solution (i.e. an efficient procurement production plan) for the whole SC. The proposed approach and solution methodology are validated through a numerical example.

Background: Malignancies are responsible for elevated HIV-related morbidity and mortality. The aim of our study was to investigate epidemiological characteristics and trends associated to malignancies occurring in the HIV-infected population in Tunisia.Methods: We conducted a retrospective analysis of all incident malignancies occurring between 1986 and 2016 among HIV-infected patients at the infectious diseases department of La Rabta Hospital in Tunis, Tunisia.Results: Seventy malignancies were diagnosed. The median age at diagnosis was 40.08 years. The majority of patients (53%) were heterosexuals, while 31% were intravenous drug users and 16% were men who have sex with men. At the time of malignancy diagnosis, average duration of HIV infection was 0,96 years. Mean CD4 cell count was equal to 192 cells/mm3. There were 52 (74 %) AIDS-defining malignancies (ADMs) and 18 (26 %) non-AIDS-defining malignancies (NADMs). The most frequent malignancies were: Kaposi sarcoma (n=30; 43 %), non-Hodgkin lymphoma (n=17; 24 %),Hodgkin lymphoma (n=9; 13 %), invasive cervical cancer (n=5; 7 %), and lung cancer (n=4; 6 %). NADMs were significantly associated with combined antiretroviral therapy (cART) initiation before cancer diagnosis (p=0.001). Frequency of NADMs increased from 6% during pre-cART era to 32% during cART era (p=0.001). After malignancy’s diagnosis, two-years overallsurvival was 42 % and mean overall survival was equal to 12 months.Conclusion: Most of diagnosed malignancies were ADMs, and Kaposi sarcoma was the most frequent malignancy. Increased frequency of NADMs was confirmed. These results suggest that efforts should be enhanced to promote HIVtesting strategies, initiate cART early, and optimize malignancies screening among HIV-infected people in Tunisia., Introduction: Les pathologies néoplasiques occupent une part importante de la morbidité et de la mortalité des personnes vivant avec le VIH (PVVIH). L’objectif était d’étudier les caractéristiques épidémiologiques et évolutives des pathologies néoplasiques survenant au cours de l’infection par le VIH en Tunisie.Méthodes: Nous avons procédé à une étude rétrospective descriptive portant sur tous les patients ayant présenté une pathologie néoplasique au cours de l’infection par le VIH et pris en charge dans le service de maladies infectieuses de l’hôpital La Rabta de Tunis entre 1986 et 2016.Résultats: Soixante-dix cas avaient été colligées. L’âge médian était de 40,08 années. Le mode de transmission du VIH était comme suit: 53% avaient une transmission hétérosexuelle, 31% étaient des usagers de drogues par voie intraveineuse et 16% étaient des hommes ayant des rapports sexuels avec des hommes. Au moment de diagnostic de cancer, la durée médiane d’évolution de l’infection par le VIH était de 0,96 année. La valeur médiane du compte de lymphocytes T CD4 était de 192 cellules/μl. Les cancers les plus fréquents étaient: le sarcome de Kaposi (n=30; 43 %), le lymphome non hodgkinien (n=17; 24 %), le lymphome de Hodgkin (n=9; 13 %), le cancer du col de l’utérus (n=5; 7 %), et le cancer du poumon (n=4 ; 6 %). Les cancers non classant SIDA étaient significativement associées à la prescription d’une thérapie antirétrovirale combinée (cART) avant le diagnostic de cancer (p=0,001). La part des cancers non classant SIDA avait augmenté de 6 % pendant la période pré-cART (1986-1999) à 32 % pendant l’ère des cART (2000-2016) (p=0,001). La survie globale (SG) était de 42 % à 2 ans et la SG médiane était égale à 12 mois.Conclusion: La majorité des cancers étaient des cancers classant SIDA et le sarcome de Kaposi était le cancer le plus fréquent. Les cancers non classant SIDA surviennent avec une fréquence croissante chez des PVVIH. Il est nécessaire de promouvoir le dépistage du VIH, d’initier précocement une cART et d’optimiser le dépistage des cancers chez les PVVIH.

Background: Malignancies are responsible for elevated HIV-related morbidity and mortality. The aim of our study was to investigate epidemiological characteristics and trends associated to malignancies occurring in the HIV-infected population in Tunisia.Methods: We conducted a retrospective analysis of all incident malignancies occurring between 1986 and 2016 among HIV-infected patients at the infectious diseases department of La Rabta Hospital in Tunis, Tunisia.Results: Seventy malignancies were diagnosed. The median age at diagnosis was 40.08 years. The majority of patients (53%) were heterosexuals, while 31% were intravenous drug users and 16% were men who have sex with men. At the time of malignancy diagnosis, average duration of HIV infection was 0,96 years. Mean CD4 cell count was equal to 192 cells/mm3. There were 52 (74 %) AIDS-defining malignancies (ADMs) and 18 (26 %) non-AIDS-defining malignancies (NADMs). The most frequent malignancies were: Kaposi sarcoma (n=30; 43 %), non-Hodgkin lymphoma (n=17; 24 %),Hodgkin lymphoma (n=9; 13 %), invasive cervical cancer (n=5; 7 %), and lung cancer (n=4; 6 %). NADMs were significantly associated with combined antiretroviral therapy (cART) initiation before cancer diagnosis (p=0.001). Frequency of NADMs increased from 6% during pre-cART era to 32% during cART era (p=0.001). After malignancy’s diagnosis, two-years overallsurvival was 42 % and mean overall survival was equal to 12 months.Conclusion: Most of diagnosed malignancies were ADMs, and Kaposi sarcoma was the most frequent malignancy. Increased frequency of NADMs was confirmed. These results suggest that efforts should be enhanced to promote HIVtesting strategies, initiate cART early, and optimize malignancies screening among HIV-infected people in Tunisia.; Introduction: Les pathologies néoplasiques occupent une part importante de la morbidité et de la mortalité des personnes vivant avec le VIH (PVVIH). L’objectif était d’étudier les caractéristiques épidémiologiques et évolutives des pathologies néoplasiques survenant au cours de l’infection par le VIH en Tunisie.Méthodes: Nous avons procédé à une étude rétrospective descriptive portant sur tous les patients ayant présenté une pathologie néoplasique au cours de l’infection par le VIH et pris en charge dans le service de maladies infectieuses de l’hôpital La Rabta de Tunis entre 1986 et 2016.Résultats: Soixante-dix cas avaient été colligées. L’âge médian était de 40,08 années. Le mode de transmission du VIH était comme suit: 53% avaient une transmission hétérosexuelle, 31% étaient des usagers de drogues par voie intraveineuse et 16% étaient des hommes ayant des rapports sexuels avec des hommes. Au moment de diagnostic de cancer, la durée médiane d’évolution de l’infection par le VIH était de 0,96 année. La valeur médiane du compte de lymphocytes T CD4 était de 192 cellules/μl. Les cancers les plus fréquents étaient: le sarcome de Kaposi (n=30; 43 %), le lymphome non hodgkinien (n=17; 24 %), le lymphome de Hodgkin (n=9; 13 %), le cancer du col de l’utérus (n=5; 7 %), et le cancer du poumon (n=4 ; 6 %). Les cancers non classant SIDA étaient significativement associées à la prescription d’une thérapie antirétrovirale combinée (cART) avant le diagnostic de cancer (p=0,001). La part des cancers non classant SIDA avait augmenté de 6 % pendant la période pré-cART (1986-1999) à 32 % pendant l’ère des cART (2000-2016) (p=0,001). La survie globale (SG) était de 42 % à 2 ans et la SG médiane était égale à 12 mois.Conclusion: La majorité des cancers étaient des cancers classant SIDA et le sarcome de Kaposi était le cancer le plus fréquent. Les cancers non classant SIDA surviennent avec une fréquence croissante chez des PVVIH. Il est nécessaire de promouvoir le dépistage du VIH, d’initier précocement une cART et d’optimiser le dépistage des cancers chez les PVVIH.

International audience; Coupling water desalination processes with Renewable Energy Sources (RESs) can be a sustainable and ecological approach to the global water/energy supply crisis. In this regard, small-scale standalone battery-less Brackish Water Reverse Osmosis (BWRO) desalination system powered by a hybrid PV/Wind RES is expected to meet freshwater demand of a small isolated community. One particularity of the proposed architecture deals with the absence of electrochemical storage; only taking benefit of hydraulic storage in water tanks when RE is available. This study puts forward the prime importance of Water/Power flows management optimization. For this purpose, an online Fuzzy Logic-based Energy Management Strategy (FLEMS) is proposed. Firstly, a Hand-Made Fuzzy Inference System (HMFIS) was designed to identify the instantaneous power sharing between the system hydro-mechanical processes (well pumping, water storage and desalination processes). Secondly, an offline genetic algorithm optimization was applied on the HMFIS design in order to optimize the power sharing factor and maximize freshwater production. Then, when applying unknown power profile, the optimized FLEMS demonstrated its performance to improve the system energy efficiency and enhance the brackish water (from 16.7% in autumn to 63% in summer) and freshwater production (to 3.3% during autumn for instance) compared with the HMFIS-based EMS.

International audience; In remote areas, the vital need is production of drinking water and the provision of electrical energy for housing.Often the only sources of energy are based on renewable energies with storage to create a local micro-network.This paper investigates the optimal design of embodied energy for water treatment by reverse osmosis, comingfrom brackish water (6 g/l) and with a double storage that is done in a drinking water tank and in batteries forelectricity. Taking account wind and photovoltaic potentials in such system for assessing its performance impliesits simulation over long periods of time. This can drastically increase the CPU time cost related to the design step,especially if the system energy management and sizing are sequentially optimized into a two-level optimizationprocess. In order to solve this problem and accelerate the system simulation, meta-models are used for representingthe system constraints and objectives. These meta-models are built by the design of experiments method. From realistic data, the results of this paper show that the contribution of the meta-models divides by two or three the design time by obtaining values of the sizing parameters close to the dynamic simulator depicting the real operation of the whole system.

International audience; In this paper, the direct approach which was introduced for the first time by [Rotella and Zambettakis, 2011] in designing minimal functional state observers is extended to deal with discrete-time systems. One of the benefits of this approach is that it does not require solving the Sylvester matrix equation that appears in other observer design procedures. Both stable observers and arbitrary fixed poles observers problems are considered for minimality. A numerical example and simulation results explain the effectiveness and the benefits of the proposed algorithm.

International audience; CuInSe2 nanoparticles (CIS-NP) were synthesized on ITO-coated glass substrate by electrodeposition and rapid thermal processing (RTP). The as-deposited films were annealed under argon atmosphere at 250 °C, 350 °C and 450 °C using RTP during a short annealing time. The latter is practicable to avoid further losing of the Se content in CIS films. In order to analyze the effect of annealing temperature, the structural, morphological, optical and electrical properties were investigated by means of X-ray diffraction, scanning electron microscopy, UV–Visible Spectroscopy and Mott-Schottky plots respectively. XRD results show that elaborated films have a tetragonal chalcopyrite CIS with preferential orientation along the (112) orientation. The phase formation of CIS-NP with good crystallinity was observed at low annealing temperature. Optical absorption studies indicate a direct band gap around 1.02 eV at 250 °C. The optical constants such as refractive index n(λ) and extinction coefficient k(λ) were estimated using an appropriate optical model. To determine the doping type of elaborated semiconductor, its flat band potential and the free carrier concentration we used the Mott-Schottky plots. A new attempt to anneal the electrodeposited CIS films by short annealing duration using RTP process was proved to be a useful method to synthesize polycrystalline CIS films for solar cell application.

International audience; In this paper, an ultra-local model control approach based on adaptive Smith predictor is proposed. The design of adaptive PID controller takes into account the estimation of variable time delay which is compensated by the addition of an adaptive Smith predictor. The purpose of this paper is to solve the online estimation problem of time delay thanks to the proposed identification method of ultra-local model parameters. A performance comparison between the proposed control approach and the Smith predictor control with classical PID is carried out. The numerical simulation results of the thermal process study with severe constraints and operating conditions show the superiority of the adaptive PID controller. The robustness with respect to noises, disturbances and system parameter uncertainties of control approaches are highlighted.

International audience; With the advent of Web search and the large amount of data published on the Web sphere, a tremendous amount of documents become strongly time-dependent. In this respect, the time dimension has been extensively exploited as a highly important relevance criterion to improve the retrieval effectiveness of document ranking models. Thus, a compelling research interest is going on the temporal information retrieval realm, which gives rise to several temporal search applications. In this article, we intend to provide a scrutinizing overview of time-aware information retrieval models. We specifically put the focus on the use of timeliness and its impact on the global value of relevance as well as on the retrieval effectiveness. First, we attempt to motivate the importance of temporal signals, whenever combined with other relevance features, in accounting for document relevance. Then, we review the relevant studies standing at the crossroads of both information retrieval and time according to three common information retrieval aspects: the query level, the document content level and the document ranking model level. We organize the related temporal-based approaches around specific information retrieval tasks and regarding the task at hand, we emphasize the importance of results presentation and particularly timelines to the end user. We also report a set of relevant research trends and avenues that can be explored in the future.

International audience; Pure and Nb doped TiO2 (TNO) thin films were deposited onto glass substrates by RF magnetron sputtering technique using a Nb and TiO2 mixture powder target at room temperature to explore the possibility of producing sputtered TNO films by a low cost process. The effect of Nb doping on the structure, morphology, optical and electrical properties of the prepared films was studied by systematically varying the Nb content from 2 to 6 wt%. GXRD results show that the deposited films mainly possess rutile phase with the (110) orientation. Raman spectra confirm that the deposited films are predominantly rutile phase. Surface roughness increases with the increase of Nb doping concentration , which may be attributed to the structural changes in the film due to the incorporation of Nb into the TiO2 lattice. Optical transmittance in the visible range reaches 85 % for the undoped films then it decreases as the doping content increases. Doping by niobium resulted in a slight increase in the optical band gap energy of the films due to the Burstein–Moss effect. The resistivity measurement of TNO films reveals that the Nb doping improves the electrical conductivity of the deposited films compared to the undoped one. The best value was observed for films deposited at 4 wt% Nb.

International audience; In this paper, the authors investigate four original methodologies for sizing a battery bank inside a passive wind turbine system. This device interacts with wind and load cycles, especially for a stand-alone application. Generally, actual wind speed measurements are of long duration which leads to extensive processing time in a global optimization context requiring a wide number of system simulations. The first part of this article outlines two sizing methodologies based on a statistical approach for the sizing of the electrochemical storage device of a stand-alone passive wind turbine system. Two other efficient methodologies based on the synthesis of compact wind speed profiles by means of evolutionary algorithms are described in the second part of this paper. The results are finally discussed with regard to the relevance of the battery bank sizing and in terms of computation cost, this later issue being crucial to an Integrated Optimal Design (IOD) process.

International audience; This paper aims at defining energy management strategy for a water pumping and desalination process which would be powered by a hybrid (solar PV & wind) renewable generation system. Several pumping subsystems for well pumping, water storage and desalination are coupled. The particularity of the proposed architecture with its management deals with the absence of electrochemical storage, only taking benefit of hydraulic storage in water tanks: in such an autonomous device, given a certain level of intermittent power following wind and sun irradiation conditions, and given hydraulic characteristics of water pumping subsystems, this study puts forward the prime importance of a water and power flow management optimization. For this purpose, both dynamic and quasi static models are proposed before stetting the management strategy based on optimal power dispatching. Subsequent results are analyzed in terms of robustness and performance.

International audience; GC-FID and GC-MS analysis of essential oils of Juniperus phoenicea resulted in the identification of 30 compounds, representing more than 98% of the total composition. α-pinene (55.7% and 80.7%), δ-3-carene (10.7% and 4.5%), and γ-cadinene (2.9% and 5.1%) were the main components, respectively, in leaves and berries essential oil. Extracts of J. phoenicea were obtained by different extraction solvents: methanol, ethanol, ethyl acetate, and dichloromethane and evaluated composition for polyphenols (gallic acid equivalent 52 to 217 g/kg), tannins (catechin equivalent 6.5 to 60.2 g/kg), antocyanins (cyanidin equivalent 84 to 373 mg/kg), and flavonoids (quercetin equivalent 6.4 to 29.3 g/kg). The samples (essential oils and extracts) were subjected to a screening for their antioxidant activity by using DPPH and ABTS assays; antimicrobial activity was tested with 6 bacteria (3 Gram-positive and 3 Gram-negative), 1 yeast, and 2 fungi. The strongest antioxidant activity was obtained by the methanolic extract (IC50= 6.5 ± 0.3 mg/L). Flavonoids are likely to contribute to the antifungal activity against Saccharomyces cerevisiae. Correlations were studied between chemical composition and antioxidant and antimicrobial activities.

PurposeThe purpose of this paper is to present a numerical and an analytical study of the thermohaline convection with Soret effect in a square enclosure filled with a binary fluid mixture.Design/methodology/approachThe horizontal boundaries of the enclosure are impermeable and heated from below while its vertical walls are assumed to be adiabatic and impermeable. The Navier‐Stokes equations under the Boussinesq‐Oberbeck approximation are solved numerically. The results are given for different values of the separation ratio. The critical Rayleigh number at the onset of convection is determined analytically and numerically. The Hopf frequency at the onset of convection is obtained.FindingsThe existence of two stable stationary bifurcation branches is illustrated. Furthermore, it is shown that the existence of stable traveling waves in the transition from one branch to the other depends on the value of the separation ratio. For some values of Rayleigh number, asymmetric flows are observed. A good agreement is found between the numerical solution and analytical analysis.Originality/valueThe present work is the first to consider thermosolutal convection with Soret effect in a square enclosure.

Cet article présente une méta-modélisation globale d’un système complexe de production d’énergie électrique et d’eau potable pour un site isolé à partir de sources renouvelables (PV et éolienne) en vue de l’utiliser dans un processus d’optimisation de dimensionnement. Ce méta-modèle est élaboré avec la méthode des plans d’expériences. L’originalité de ce travail est d’avoir combiné cette approche pour une application aussi complexe (possédant 3 éléments de stockage). C’est pour cela qu’un travail important a été fourni pour définir la forme des équations, les indicateurs de performance et aussi de faire intervenir dans ces équations tous les paramètres intervenant dans le dimensionnement. Des résultats sont donnés en fin d’article qui illustrent l’optimisation de l’énergie grise sur cycle de vie du système complet.

This paper deals with the design of an ultra­ local model control. The proposed approach is based on the estimation of the ultra-local model parameters using least squares resolution technique instead of numerical derivation technique. The closed-loop control is implemented through an adaptive PI in order to reject the influences of the dis­ turbance and noise output signais. Its main advantages are: its simplicity and its robustness with respect to the parame­ ter uncertainties of system. In this paper, it is processed to test the efficiency of the parameter estimation method com­ pared with the performance of numerical derivation tech­ nique. The method is applied to the water level control of a two-tank-system. Numerical simulations show that the gen­ erated desired trajectory is followed in an efficient way even with severe operating conditions.

International audience; The pike-perch is among the economically most valuable fish species for both commercial and recreational fishermen. This could be seen as the main reason for its introductions into Western Europe (including France) and Tunisia. Knowledge of the genetic structure of the introduced populations is a prerequisite for their successful long-term management. The present study focuses on the genetic characterization of introduced Tunisian and French pike-perch populations using species-specific microsatellite loci and mitochondrial cytochrome b haplotypes in order to better understand their genetic relationships and to try to trace the origin of the Tunisian populations. Lowered levels of genetic diversity have been observed in the two introduced Tunisian populations and a farmed Czech strain compared to a native wild German population. The reduction of microsatellite genetic variability of these three populations was supported by a genetic bottleneck signature. In contrast, the French populations showed high genetic diversity, probably due to multiple introductions and admixture of genetically differing sources. A high genetic differentiation level (significant F-ST values) between most pike-perch populations and a high average accuracy of self-assignments of individuals to populations of their origin were observed, probably resulting from genetic drift. The average pairwise relatedness values and results of the structure analysis highlighted a closer relationship between Tunisian and French populations than between Tunisian and German ones. Indeed, the two Tunisian populations clustered together with the French populations on a Neighbour-Joining tree based on D-A genetic distances. This was also sustained by the distribution of cytochrome b haplotypes A and B in the studied populations. The present results demonstrate that, despite the genetic differences, the studied populations cluster according to their phylogeographic origin. The Tunisian populations seem to be introduced from a French hatchery where the brood stock had the haplotype B of the mitochondrial cytochrome b gene.

An off-grid energy system based on renewable photovoltaics (PV) and wind turbines (WT) generators is coupled via converters to electric and hydraulic networks. The electric network is composed of consumers and of a battery bank for electrical storage, while the hydraulic part is made of motor-pumps and hydraulic tanks for water production and desalination. Both battery and water tanks are used to optimize the power management of both electric and hydraulic subsystems by ensuring electric load demand and by reducing at the same time water deficit following the operation of the renewable intermittent source. Thus, both electric and hydraulic subsystems are strongly coupled in terms of energy making necessary to manage the power flows provided by renewable sources to optimize the overall system performance. In this paper, two kinds of management strategies are then compared in the way they share the hybrid power sources between the storage devices (battery and tanks) and the electrical/hydraulic loads. The first approach deals with an “uncoupled power management” in which the operation of electrical and hydraulic loads does not depend on the state of the intermittent renewable sources: in particular, hydraulic pumps are operated only taking account of water demand and tank filling but without considering power sources. On the contrary, given the available power produced by the sources, the second class of strategy (i.e. the “coupled management strategy”) consists of a “smart” power sharing between the electrical and hydraulic networks with regard to the battery SOC and the tank L 1 and L 2 . A dynamic simulator of the hybrid energy system has been developed and tested using a MATLAB environment. The system performance is shown under the two investigated approaches (uncoupled vs coupled). Several tests are carried out using real meteorological data of a remote area and a practical load demand profile. The simulation results show that the “coupled strategy” clearly outperforms the classical “uncoupled” management strategies.

International audience; This paper is devoted to an experimental comparison between two different methods of ultra-local model control. The concept of the first proposed technique is based on the linear system resolution technique to estimate the ultra-local model parameters. The second proposed method is based on the linear adaptive observer which allows the joint estimation of state and unknown system parameters. The closed-loop control is implemented via an adaptive PID controller. In order to show the efficiency of these two control strategies, experimental validations are carried out on a two-tank system. The experimental results show the effectiveness and robustness of the proposed controllers.

International audience; In this paper, we tackle the issue related to the retrieval of the best evidence that fits with a PICO (Population, Intervention, Comparison and Outcome) question. We propose a new document ranking algorithm that relies on semantic based query expansion bounded by the local search context to better discard irrelevant documents. Experiments using a standard dataset including 423 PICO questions and more than 1,2 million of documents, show that our aproach is promising.

International audience; This paper deals with a new parameter estimation method for an ultra-local model of Broïda. The proposed approach is based on the algebraic derivation techniques and the linear system resolution method, in order to estimate the ultra-local model parameters, such that the variable time-delay. The closed-loop control is achieved via an adaptive PI controller to reject the influence of noises and disturbances. A simulation results of a thermal process application are given to validate the effectiveness of the proposed strategy. A performance comparison with a classical PID controller is achieved.

International audience; In this paper, we present a new algorithm of sliding window identification with linear-equality constraints. This algorithm consists in firstly deleting the oldest set of data and in secondly adding the last set of data. The method developed in this paper allows to consider at every step a set of new data by an extension of their result. The proposed algorithm is based on the recursive calculus of the pseudo-inverse matrix from the forms of Albert and Sittler. A simple and easily implementable initialization of the constrained algorithm is proposed. An improvement is obtained by removing the influence of oldest set of data and by satisfying the linear-equality constraints. It is shown that the solutions of the sliding window identification algorithm converge to the true parameter that satisfies the equality constraints. Numerical example is provided to show the effectiveness of the proposed method.

International audience; In this paper, a new adaptive controller is proposed for ultra-local model based control. The concept is based on the algebraic derivation techniques to estimate the two ultra-local model parameters. A comparison study with the control method of Fliess-Join which is based on some elementary differential algebra is developed. The robustness of the ultra-local model controllers with respect to noises, external disturbances and parameter uncertainties is highlighted. The control strategies are successfully tested via the control of a two-tank nonlinear system. Different numerical simulations show the effectiveness of the proposed controller.

International audience; Bifacial solar cells combining a heterojunction cell on the upper side and crystalline silicon (c-Si) homojunction on the backside are very interesting devices to a more efficient use of the solar radiation. Cu(In,Ga)Se 2 (n)/c-Si(p)/c-Si(n +) or CuInSe 2 (n)/c-Si(p)/c-Si(n +) are very attractive heterojunctions to reach this target. In this work, a novel attempt has been made to grow CuInSe 2 thin films on p-Si (100) substrate using one-step electrodeposition route with galvanostatic mode. The as-deposited samples were amorphous by nature which implies a rapid thermal annealing step. The effect of annealing temperature on the structural, morphological, optical and electrical properties of the fabricated hetero-structure CuInSe 2 /c-Si (100) was investigated by x-ray diffraction (XRD), scanning electron microscopy, energy dispersive spectroscopy (EDS) and UV-visible spectroscopy. XRD indicates that CuInSe 2 films having single phase chalcopyrite with tetragonal crystal structure are obtained at 350°C. Values of energy band gap of films at various annealing temperature were estimated to be in the range 0.94-1.01 eV. The optical parameters such as refractive index n(λ) and extinction coefficient k(λ) were estimated using an appropriate optical model. The AM1.5 current density-voltage characteristic of the fabricated Al/CuInSe 2 /c-Si (100) hetero-junction solar cell exhibits a short-circuit current density J sc of 4.06 mA cm −2 , an open circuit voltage V oc of 0.28 V, a fill factor FF of 36.72% and a solar conversion efficiency η of 0.41%.

International audience; In this paper, we give an overview of our participation in the timeline generation task of SemEval-2015 (task 4, TimeLine: Cross-Document Event Ordering). The main goals of this new track are, given a collection of news articles and a so-called target entity, to determine events that are relevant for the entity, to resolve event coreferences, and to order the events chronologically. We addressed thesub-tasks, in which event mentions were provided, i.e., no additional event extraction was required. For this, we developed an ad-hoc approach based on a temporal tagger and a coreference resolution tool for entities. After determining relevant sentences, relevant events are extracted and anchored on a timeline. The evaluation conducted on three collections of news articles shows that our approach – despite its simplicity – achieves reasonable results and opens several promising issues for future work.

This paper proposes a metamodel design for a Photovoltaic/Wind/Battery Energy System. The modeling of a hybrid PV/wind generator coupled with two kinds of storage i.e. electric (battery) and hydraulic (tanks) devices is investigated. A metamodel is carried out by hybrid spline interpolation to solve the relationships between several design variables i.e. the design parameters of different subsystems and their associate response variables i.e. system indicators performance. The developed model has been successfully validated under real test conditions.

International audience; This paper describes the IRIT lab participation to the TREC 2015 Temporal Summarization track. The goal of the Temporal Summarization track is to develop systems that allow users to efficiently monitor information about events over time. To tackle this task, we proposed three different methods. Obtained results are presented and discussed.

International audience; In this paper, a new ultra-local model control approach is proposed. The concept is based on the linear adaptive observer to estimate the ultra-local model parameters instead of algebraic derivation technique. The importance of adaptive observer is deduced in the join estimation of state and unknown parameters of parametric systems. The closedloop control is implemented via an adaptive PID controller to reject disturbances due to exogenous parameter uncertainties. In this paper, a performance comparison between the adaptive observer based method and the algebraic derivation technique is developed to show the efficiency of the proposed control strategy. The approaches are applied to a two-tank system for the water level control. Several successful simulation results are shown to demonstrate the effectiveness of the proposed controller.

International audience; Recently, an increasing number of information retrieval studies have triggered a resurgence of interest in redefining the algorithmic estimation of relevance, which implies a shift from topical to multidimensional relevance assessment. A key underlying aspect that emerged when addressing this concept is the aggregation of the relevance assessments related to each of the considered dimensions. The most commonly adopted forms of aggregation are based on classical weighted means and linear combination schemes to address this issue. Although some initiatives were recently proposed, none was concerned with considering the inherent dependencies and interactions existing among the relevance criteria, as is the case in many real-life applications. In this article, we present a new fuzzy-based operator, called iAggregator, for multidimensional relevance aggregation. Its main originality, beyond its ability to model interactions between different relevance criteria, lies in its generalization of many classical aggregation functions. To validate our proposal, we apply our operator within a tweet search task. Experiments using a standard benchmark, namely, Text REtrieval Conference Microblog,1 emphasize the relevance of our contribution when compared with traditional aggregation schemes. In addition, it outperforms state-of-the-art aggregation operators such as the Scoring and the And prioritized operators as well as some representative learning-to-rank algorithms.

International audience; Video watermarking is very important in many areas of activity and especially in multimedia applications. Therefore, security of video stream has recently become a major concern and has attracted more and more attention in both the research and industrial domains. In this perspective, several video watermarking approaches are proposed but, based on our knowledge, there is no method which verified the compromise between invisibility and robustness against all usual attacks. In our previous work, we proposed a new video watermarking approach based on feature region generated from mosaic frame and multi-frequential embedding. This approach allowed obtaining a good invisibility and robustness against the maximum of usual attacks. In our future work, we propose to optimize the choice of the region of interest by using crowdsourcing technique. This last one is an emerging field of knowledge management that involves analyzing the behavior of users when they

International audience; In this work, we give an overview of our participation in the TREC 2014 Contextual Suggestion Track. To address the retrieval of attraction places, we propose a fuzzy-based document combination approach for preference learning and context processing.We use the open web in our submission and make use of both criteria users preferences and geographical location criteria.

International audience; On propose dans le présent article, une stratégie de commande par platitude des systèmes multi-entrées multi-sorties linéaires non stationnaires en vue de réaliser la poursuite de trajectoires de référence. La synthèse de la loi de commande est basée sur le développement d’un observateur exact permettant la conception d’un régulateur polynomial à deux degrés de liberté sans passer par la résolution de l’équation de Bézout généralisée dans le cas non stationnaire. Cette approche est appliquée à la commande de systèmes non linéaires par linéarisation autour de trajectoires données. L’approche proposée est appliquée sur le modèle du satelliteSPOT-5.

Sl-ERF.B.3 (Solanum lycopersicum ethylene response factor B.3)gene encodes for a tomato transcription factor of the ERF (ethylene responsive factor) family. Our results of real-time RT-PCR showed thatSl-ERF.B.3is an abiotic stress responsive gene, which is induced by cold, heat, and flooding, but downregulated by salinity and drought. To get more insight into the role ofSl-ERF.B.3in plant response to separate salinity and cold, a comparative study between wild type and twoSl-ERF.B.3antisense transgenic tomato lines was achieved. Compared with wild type,Sl-ERF.B.3antisense transgenic plants exhibited a salt stress dependent growth inhibition. This inhibition was significantly enhanced in shoots but reduced in roots, leading to an increased root to shoot ratio. Furthermore, the cold stress essay clearly revealed that introducing antisenseSl-ERF.B.3in transgenic tomato plants reduces their cell injury and enhances their tolerance against 14 d of cold stress. All these results suggest thatSl-ERF.B.3gene is involved in plant response to abiotic stresses and may play a role in the layout of stress symptoms under cold stress and in growth regulation under salinity.

National audience; Dans ce papier, nous proposons une nouvelle approche d’agrégation personnalisée pour l’estimation de la pertinence multidimensionnelle. L’approche est basée sur un opérateur d’agrégation mathématique qui utilise une mesure floue permettant la quantification de l’importance estimée des critères pour chaque utilisateur ainsi que leur degré d’interactivité ou d’interdépendance. Nous évaluons l’opérateur d’agrégation proposé en utilisant la collection de test standard fournie avec par la tâche “Contextual Suggestion” de TREC 2013. Les résultats expérimentaux obtenus montrent l’impact de la personnalisation sur les performances de recherche.

International audience; It is shown that by the use of flatness the problem of pole placement, which consists in imposing closed-loop system dynamics, can be related to track desired trajectories in the finite-dimensional linear time-invariant case. Polynomial two-degree-of-freedom controller can then be designed with the use of an exact observer and without resolving the Bézout's equation. In this paper, an extension of these developments is proposed in the linear time-varying (LTV) framework. The proposed approach is illustrated with the control of nonlinear model of an anti-lock brake system. The time-varying controller obtained from the LTV model ensures the trajectory tracking of the nonlinear model.

International audience; In this paper, a flatness-based control strategy for multi-input multi-output linear time-varying systems is proposed in order to track desired trajectories. The control design, based on the use of an exact observer, leads to a polynomial two-degree-of-freedom controller without resolving Bézout’s equation in a time-varying framework. The proposed approach is illustrated with the control of a nonlinear model of the satellite SPOT-5.

International audience; Areas polluted by the persistent presence of metal(loid)s induce health problems, especially when recreational activities (on land or water) promote human exposure to the pollutants. This study focuses on one of the most encountered worldwide mining waste, i.e. those from the extraction of Pb–Zn–Ag. The representative Pb–Zn-rich tailing (about 64, 100 m3) sampled is located near a soccer field and a famous river for fishing. The scientific interests is relative to: (1)mobility and bioaccessibility of metal(oid)s, (2) human risk assessments and (3) relationship between human risks and solid-bearing phases in the environment. Soccer field soils, tailings and sediments from the nearby river were sampled; moreover,metal(loid) speciation (fromBCR experiments) and bioaccessibility were measured and solid speciation performed by X-ray diffraction and electron microscopy in order to highlight metal(loid) dispersion and impact. Results demonstrate that the soccer field is highly contaminated by Pb, Zn, As and Sb due primarily to waste runoff. In terms of risk assessment, Pb and As human bioaccessibility highlights the major health risk (48 and 22.5 % of human bioaccessibility, respectively). Since local populations are regularly in close contact with metal(loid)s, the health risk due to pollutant exposure needs to be reduced through sustainable waste disposal and the rehabilitation of polluted sites.

International audience; Dans ce papier, nous nous intéressons à étudier le problème de l'agrégation multicritères dans le domaine de la recherche d'information (RI). Nous proposons une nouvelle approche basée sur l'intégrale de Choquet pour l'agrégation de pertinence multidimensionnelle. La principale originalité de cet opérateur, outre sa capacité à modéliser des interactions entre les différentes dimensions de pertinence, est sa capacité à généraliser de nombreuses fonctions d'agrégation classiques. L'évaluation de l'efficacité de notre approche est effectuée dans une tâche de recherche de tweets, où les critères conjointement utilisés sont, la pertinence thématique, l'autorité et la fraîcheur. Les résultats expérimentaux obtenus sur la collection de test fournie par la tâche Microblog de TREC 2011 montrent la pertinence de notre proposition.

International audience; In this paper, the authors face the problem of wind speed processing as environmental variable of a wind turbine system. Generally, the information on wind speed measurements is processed over long periods of time to be relevant with respect to the site characteristics (average and maximum speeds, statistics). Subsequent large scale profiles of wind speed lead to long processing time for simulation analysis and especially for optimization design that penalizes the search of optimal solutions. An original synthesis approach of a compact and representative wind speed profile using an Evolutionary Algorithm (EA) is proposed. This approach is compared to a purely statistical approach based on random number generators. It allows reducing the actual wind profile duration with compression ratios greater (two months of wind speed measurements are compressed in only 1 hour). Then, the synthesis approach by EA is applied to the sizing of an autonomous hybrid system based on wind turbine with battery storage for stand-alone energy systems. It has proven its effectiveness in reducing 200 days of wind speed measurements in only 10 days, allowing sizing the storage system with a significant gain in terms of computing time in the framework of the optimization process.

In this paper, the authors investigate two methodologies for synthesizing compact wind speed profiles by means of evolutionary algorithms. Such profile can be considered as input parameter in a prospective design process by optimization of a passive wind system with storage. Compact profiles are obtained by aggregating elementary patterns in order to fulfil some target indicators. The main difference between both methods presented in the paper is related to the choice of these indicators. In the first method, they are related to the storage system features while they only depend on wind features in the second.

International audience; In this paper, we present the design of ultra wideband (UWB) planar Five-Port Reflectometer using the elliptic coupler which has the advantage to offer a wide bandwidth compared to the hybrid one. The elliptic coupler and the five-port circuit were designed and simulated in the 1.5 to 3.5 GHz band using ADS software of Agilent. An analytical calculus and simulation results of a five-port circuit using elliptic coupler demonstrate limitations of this structure.

Ontologies have an important role in knowledge organization and information retrieval. Domain ontologies are composed of concepts represented by domain relevant terms. Existing approaches of ontology construction make use of statistical and linguistic information to extract domain relevant terms. The quality and the quantity of this information influence the accuracy of terminologyextraction approaches and other steps in knowledge extraction and information retrieval. This paper proposes an approach forhandling domain relevant terms from Arabic non-diacriticised semi-structured corpora. In input, the structure of documentsis exploited to organize knowledge in a contextual graph, which is exploitedto extract relevant terms. This network contains simple and compound nouns handled by a morphosyntactic shallow parser. The noun phrases are evaluated in terms of termhood and unithood by means of possibilistic measures. We apply a qualitative approach, which weighs terms according to their positions in the structure of the document. In output, the extracted knowledge is organized as network modeling dependencies between terms, which can be exploited to infer semantic relations.We test our approach on three specific domain corpora. The goal of this evaluation is to check if our model for organizing and exploiting contextual knowledge will improve the accuracy of extraction of simple and compound nouns. We also investigate the role of compound nouns in improving information retrieval results.

In this paper, an original optimization method to jointly determine a reduced study term and an optimum battery sizing is investigated. This storage device is used to connect a passive wind turbine system with a stand alone network. A Weibull probability density function is used to generate different wind speed data. The passive wind system is composed of a wind turbine, a permanent magnet synchronous generator feeding a diode rectifier associated with a very low voltage DC battery bus. This study is essentially based on a similitude model applied on an 8 kW wind turbine system. Our reference model is taken from a 1.7 kW optimized system. The wind system generated power and the load demand are coupled through a battery sized using a statistical approach.

International audience; The linear stability of a plane layer with horizontal temperature and concentration stratification corresponding to gradient zone of a solar pond is investigated. The problem is described by Navier-Stokes equations with Boussinesq-Oberbeck approximation. Two source terms are introduced in the energy equations: the absorption of solar energy characterized by the extinction radiative coefficient μe and by the parameter f defined as the ratio of extracted heat flux to absorbed heat flux in the lower convective zone. The influence of the parameters μe and f on the onset of thermosolutal convection in the case of confined and infinite layers is analyzed. It is found that convection starts in an oscillatory state, independently of the RaS value. Different convection solutions were found for marginal stability and steady state.