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Larval interference competition between the native Neotropical mosquito Limatus durhamii and the invasive Aedes aegypti improves the fitness of both species

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Insect science 2018年第6期25卷 1102-1107页

作者： stanislas Talaga Alain Dejean Clémence Mouza Yves Dumont Céline Leroy lnsUtut Pasteur de la Guyane Unitéd'Entomologie MédicaleCayenne cedexFrance CNRs UMR EcoFoGAgroParisTechCiradINRAUniversitédes AntillesUniversitéde GuyaneKourouFrance CNRs INPTUPSEcolabUniversitéde ToulouseToulouseFrance AMAP CIRADCNRSINRAIRDUniversit6MontpellierMontpellierFrance

Interspecific competition with native species during biological invasions can sometimes limit alien *** aimed to determine the potential ecological effects of Limatus durhamii Theobald 1901,a native Neotropical mosquito (Diptera:Culicidae) species,on the invasive species Aedes (stegomyia)aegypti (Linnaeus 1762)that breeds in the same artificial water *** time and adult dry mass were measured in 3 rearing conditions:control (a single larva),intraspecific competition (2 conspecific larvae),and interspecific competition (2 heterospecific larvae).Food was provided ad libitum to eliminate exploitative *** ***,development time was not affected by interspecific interference competition (nonsignificant differences with the control)and the adult dry mass was significantly higher,meaning that individual fitness likely ***,because previous studies showed longer development time and lighter adults during competition with other invasive mosquitoes,it is likely that *** can express a different phenotype depending on the competing *** similar pattern found for *** females and the nonsignificant difference with the control for males explain in part why this species can compete with ***.

关键词： Aedes aegypti increased fitness interference competition Limatus durhamii phenotypic plasticity resistance to invasion

Characterization of Tunisian marine sediments in Rades and Gabes harbors

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International Journal of sediment Research 2014年第3期29卷 391-401页

作者： Imen BEL HADJ ALI Zoubeir LAFHAJ Mounir BOUAssIDA Imen sAID Ecole Centrale de Lille Villeneuve d'AscqFrance and Ecole Nationale d'Ingenieurs de TunisTunisia Ecole centrale de Lille Villeneuve d'AscqFrance Universite de Tunis El Manar/Ecole nationale d'Ingenieurs de Tunis/05-UR-11 06 Universite de Tunis El Manar/Ecole nationale d'Ingenieurs de Tunis/05-UR-1106

The objective of this article is to study the geotechnical and environmental characteristics of sediments dredged from two Tunisian harbors:Rades and *** first harbor represents the main facility place in the national transport *** second one is selected as its sediments present a serious ecological constraint caused by the discharge of wastes into the marine *** sediments are either discarded at sea or landfilled despite their harmful effects on the *** article is divided into three main *** first one presents the material that was carried for Rades and Gabes *** conservation conditions and the used experimental tests are *** characterization includes the determination of the grain size distribution,the water content,the Atterberg limits,the methylene blue value,the specific area,the bulk density,the specific unit weight,the organic and carbonate *** characterization is assessed by the determination of metals concentrations in a leaching *** second section deals with the description and analysis of geotechnical properties of Rades and Gabes harbors’ *** results obtained show that Rades harbor sediments are slightly sandy clayey silts whereas Gabes harbor sediments are silty sands characterized by a highly plastic clay *** of the two sediments don’t exhibit a high organic ***,chemical,mineralogical and environmental properties are presented and then *** experimental results obtained show that Rades and Gabes sediments could be used as a sand substitute in the formulation of a new construction *** harbor sediments are more polluted than Rades harbor sediments.

关键词： sediments Characterization Geotechnical Environmental Valorization

Regional gradient observability for semilinear hyperbolic systems： HUM approach

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Control Theory and Technology 2018年第1期16卷 72-80页

作者： Adil KHAZARI Ali BOUTOULOUT Imad EL HARRAKI sidi Mohamed Ben Abdellah University Ecole Nationale de Commerce et de gestion Fez Morocco TsI Team MACS Laboratory Faculty of Sciences Moulay Ismail University Meknes Morocco Ecole nationale superieure des mines de Rabat Rabat Morocco

The paper aims to extend the notion of regional observability of the gradient to the semilinear hyperbolic case, in order to reconstruct the gradient of the initial conditions in a subregion w of the domain evolution Ω. We start with an asymptotically linear system, the approach is based on an extension of the Hilbert uniqueness method （HUM） and schauder＇s fixed point theorem. The analysis leads to an algorithm which is successfully numerically implemented and illustrated with examples and simulations.

关键词： Distributed systems fixed point regional gradient observability regional reconstruction semilinear hyperbolic systems

Mechanical Characterisation of Interface for steel/Polymer Composite Using Pull-out Test: shear-Lag and Frictional Analysis

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Journal of Materials science & Technology 2006年第4期22卷 552-558页

作者： Mohamed KHARRAT Maher DAMMAK Amine CHARFI Institut Préparatoire aux Etudes d'Ingénieurs de sfax Tunisia Laboratoire des Systèmes ElectromécaniquesEcole Nationale d'Ingénieurs de SfaxTunisia Laboratoire des systèmes Electromécaniques Ecole Nationale d'Ingénieurs de SfaxTunisia

Fibre-matrix interface is known to have contribution to the mechanical performance of fibre-reinforced composite by its potential for load transfer between the fibre and the matrix. such load transfer is of great importance in dentistry when a post is used for fixing a ceramic crown on the tooth. In this study, a pull-out test was carried out to analyse the interfacial properties of a steel fibre embedded in a polyester and epoxy matrices. It was found that the fibre-matrix interface is debonded on the whole embedded length when the fibre stress reached the debonding stress. Then, the fibre stress fell down to the initial extraction stress required to pulling out the debonded fibre from the matrix. Both debonding stress and initial extraction stress initiated a linear increase with the implantation length after the debonding stress reached horizontal asymptotes. To analyse the fibre-matrix load transfer before debonding, an analytical shear-lag model was adopted to in this test conditions. Fitting the experimental results with the analytical model provided the interfacial shear strength. By considering the Coulomb friction at the fibre-matrix interface during the fibre extraction process, an analytical model which considers Poisson＇s effects on both fibre and matrix, was developed. In this model, knowledge of the initial extraction stress of the fibre provides the residual normal stress at the fibre-matrix interface.

关键词： Fibre Matrix Interface Pull-out shear-lag Debonding Friction

GENERALIZATION OF THE INTERACTION BETWEEN HAAR APPROXIMATION AND POLYNOMIAL OPERATORs TO HIGHER ORDER METHODs

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Analysis in Theory and Applications 2006年第4期22卷 301-318页

作者： Fran ois Chaplais école nationale supérieure des Mines de Paris France

In applications it is useful to compute the local average empirical statistics on u. A very simple relation exists when of a function f（u） of an input u from the local averages are given by a Haar approximation. The question is to know if it holds for higher order approximation methods. To do so, it is necessary to use approximate product operators defined over linear approximation spaces. These products are characterized by a strang and Fix like condition. An explicit construction of these product operators is exhibited for piecewise polynomial functions, using Hermite interpolation. The averaging relation which holds for the Haar approximation is then recovered when the product is defined by a two point Hermite interpolation.

关键词： strang and Fix conditions product approximation Hermite interpolation wavelets

Active Queue Management Exploiting the Rate Information in TCP-IP Networks

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IEEE/CAA Journal of Automatica sinica 2018年第1期5卷 223-231页

作者： Abderrahmane Boudi Malik Loudini Laboratoire de la Communication dans les systemes Informatiques Ecole nationale Superieure d'Informatique ESI Algiers 16309 Algeria IEEE

In this paper, we propose a new mechanism called explicit rate notification(ERN) to be used in end-to-end communications. The ERN scheme encodes in the header of transmission control protocol(TCP) packets information about the sending rate and the round trip time(RTT) of the flows. This new available information to the intermediate nodes(routers) is used to improve fairness, increase utilization, decrease the number of drops, and minimize queueing delays. Thus, it induces a better management of the queue. A comparison of our scheme with preexistent schemes, like the explicit congestion notification scheme, shows the effectiveness of the proposed mechanism.

关键词： Active queue management congestion control fairness transmission control protocol(TCP)

Integration of automatic voltage regulator and power system stabilizer: small-signal stability in DFIG-based wind farms

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Journal of Modern Power systems and Clean Energy 2019年第5期7卷 1115-1128页

作者： sirine EssALLAH Adel BOUALLEGUE Adel KHEDHER Universite de sousse Ecole Nationale d’Ingenieurs de SousseLATIS-Laboratory of Advanced Technology and Intelligent Systems4023 SousseTunisia

The increasing penetration of wind farms in the energy sector directly affects the dynamic behavior of the power *** increasing use of wind energy in the power system worsens its stability and inherently influences the firmness of a small *** investigate these effects,one of the synchronous generators(sGs)of the grid is considered defective and is replaced by a doubly fed induction generator(DFIG)-based wind farm of the same *** small-signal stability of a power system is usually evaluated via eigenvalue analysis where local-area and inter-area oscillatory modes for the New England test system are *** controls,such as automatic voltage regulator(AVR)and power system stabilizer(Pss),are added to attenuate the generated *** this study,the impact of wind energy on the small-signal stability of the power system is *** combinations of AVR and Pss types are considered to mitigate the undesirable alterations.A comparative study is performed based on numerical simulations to choose the best combination of AVR and Pss *** obtained results prove that the proposed combination yields good results in terms of stability enhancement both under normal operating conditions and in DFIG-based wind farms.

关键词： Power system stability Power transmission system Transient analysis Voltage regulation

Cameroon Climate Predictions Using the sARIMA-LsTM Machine Learning Model: Adjustment of a Climate Model for the sudano-sahelian Zone of Cameroon

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Open Journal of statistics 2024年第3期14卷 394-411页

作者： Joseph Armathé Amougou Isidore séraphin Ngongo Patrick Forghab Mbomba Romain Armand soleil Batha Paul Ghislain Poum Bimbar Dpartement de Gographie Universit de Yaound 1 Yaound Cameroon Observatoire National sur les Changements Climatiques (ONACC) Yaound Cameroon Laboratoire dAnalyse et Modlisation Multidisciplinaire statistique (sAMM) Universit de Paris 1 Panthon Sorbonne Paris France Ecole nationale suprieure Polytechnique de Yaound 1 Yaound Cameroon Dpartement de Mathmatiques Ecole Normale Suprieure de Yaound Yaound Cameroon Dpartement dInformatique Universit de Yaound 1 Yaound Cameroon

It is acknowledged today within the scientific community that two types of actions must be considered to limit global warming: mitigation actions by reducing GHG emissions, to contain the rate of global warming, and adaptation actions to adapt societies to Climate Change, to limit losses and damages [1] [2]. As far as adaptation actions are concerned, numerical simulation, due to its results, its costs which require less investment than tests carried out on complex mechanical structures, and its implementation facilities, appears to be a major step in the design and prediction of complex mechanical systems. However, despite the quality of the results obtained, biases and inaccuracies related to the structure of the models do exist. Therefore, there is a need to validate the results of this sARIMA-LsTM-digital learning model adjusted by a matching approach, “calculating-test”, in order to assess the quality of the results and the performance of the model. The methodology consists of exploiting two climatic databases (temperature and precipitation), one of which is in-situ and the other spatial, all derived from grid points. Data from the dot grids are processed and stored in specific formats and, through machine learning approaches, complex mathematical equations are worked out and interconnections within the climate system established. Through this mathematical approach, it is possible to predict the future climate of the sudano-sahelian zone of Cameroon and to propose adaptation strategies.

关键词： Adjustment Calibration Climate sudano-sahelian Zone Numerical Model

seed wasp invasions promoted by unregulated seed trade affect vegetal and animal biodiversity

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Integrative Zoology 2012年第3期7卷 228-246页

作者： Marie-Anne AUGER-ROZENBERG Alain ROQUEs French National Institute for Agricultural Research(inra) Forest Ecology(UR633)OrleansFrance

Cone and seed insects are considered the most important predators of tree seeds during the pre-dispersal phase of *** them,exotic seed chalcids in the genus Megastigmus invaded Europe as a result of the rapidly-increasing and mostly unregulated seed trade for afforestation and ornamental *** their economic impact in seed orchards,until recently,little attention was paid to the ecological impact of these *** the present study,selected case studies of alien Megastigmus *** considered to assess their specific impact on the potential of natural regeneration of native woody plants and on the native entomofauna competing for seed *** re-analyzed data from former studies that did not focus on these ecological interactions and,here,present previously unpublished *** of Douglas-fir,true cedars,true firs and wild roses were sampled all over Europe,and the relative importance of the native and invasive chalcid species was assessed as well as their specific impact on seed *** most cases,the recent arrival of alien chalcids resulted in a significant decrease in the regeneration potential of the host *** the absence of competitors,alien chalcids occupied the entire seed niche in Douglas-fir,but their impact tended to decrease after the arrival of invasive seed *** firs,alien chalcids tended to displace the native chalcids,but not in wild roses and cedars,where their damage was *** biological traits that might explain invasive success of alien chalcids are ***,no general invasive patterns seem to exist.

关键词： ecological impact invasion Megastigmus seed trade