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Wellposedness of some quasi-linear Schrdinger equations

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Science China Mathematics 2015年第5期58卷 891-914页

作者： CHEMIN Jean-Yves SALORT Delphine Laboratoire J.-L. Lions UMR 7598 Universit'e Pierre et Marie Curie Laboratoire de Biologie Computationnelle et Quantitative UMR 7238Sorbonne Universit'es L'Institut Jacques Monod UMR 7592 Universit'e Paris Diderot

This article is devoted to the study of a quasilinear Schrodinger equation coupled with an elliptic equation on the metric g. We first prove that, in this context, the propagation of regularity holds which ensures local wellposedness for initial data small enough in H1/2 and belonging to the Besov space B3/2 2,1. In a second step, we establish Strichartz estimates for time dependent rough metrics to obtain a lower bound of the time existence which only involves the B1＋ε 2,∞ norm on the initial data.

关键词： quasilinear Schrodinger equation Strichartz estimates paradiffential calculus stationary phase method

Water extraction kinetics of metals, arsenic and dissolved organic carbon from industrial contaminated poplar leaves

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Journal of Environmental Sciences 2013年第12期25卷 2451-2459页

作者： Muhammad Shahid Tiantian Xiong Maryse Castrec-Rouelle Tibo Leveque Camille Dumat Department of Environmental Sciences COMSATS Institute of Information Technology University of Toulouse INP-ENSATAv of Agrobiopole umr 5245 CNRS-INP-UPS EcoLab umr 7618 BioEmco UPMC-Paris 6

In industrial areas, tree leaves contaminated by metals and metalloids could constitute a secondary source of pollutants. In the present study, water extraction kinetics of inorganic elements （IE： Pb, Zn, Cd, As, Fe and Mn）, dissolved organic carbon, pH and biological activity were studied for industrial contaminated poplar leaves. Moreover, the distribution of the IE through the size fractions of the associated top soil was measured. High quantities ofMn, Zn and As and polysaccharides were released in the solution from the strongly contaminated leaves. The kinetic of release varied with time and metal type. The solution pH decreased while dissolved organic contents increased with time after 30 days. Therefore, these contaminated leaves could constitute a source of more available organic metals and metalloids than the initial inorganic process particles. However, the distribution of the IE through the size fractions of the top soil suggested that a great part of the released IE was adsorbed, reducing in consequence their transfers and bioavailability. It＇s concluded that mobility/boioavailability and speciation of metals and metalloids released from the decomposition of polluted tree leaves depends on soil characteristics, pollutant type and litter composition, with consequences for environmental risk assessment.

关键词： metals and metalloids dissolved organic carbon litter decomposition kinetics speciation water extraction

On visualization techniques comparison for large social networks overview:A user experiment

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Visual Informatics 2020年第4期4卷 23-34页

作者： Bruno Pinaud Jason Vallet Guy Melancn University of Bordeaux CNRS UMR 5800 LaBRIFrance

Visualizing social networks,especially an overview emphasizing their structure,i.e.,communities and their interconnections,is known to be a challenging *** this paper,we present a set of design rationales to build such overview visualizations of social networks and our solution called *** evaluate its performances against two of the most wide-spread visualization techniques(matrix and node-link diagram)in a human–computer controlled experiment based on community-related *** none of the techniques emerge as the overwhelming winner,Jasper appears to be one of the best methods for each task;a fact sustained by the marks given by the ***,Jasper can be seen as an all-encompassing solution for quickly producing legible and compact overviews of large social networks on a single modern computer.

关键词： Overview visualization User evaluation Graphs andnetworks Social networks

Porous media grain size distribution and hydrodynamic forces effects on transport and deposition of suspended particles

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Journal of Environmental Sciences 2017年第3期29卷 161-172页

作者： Nasre-Dine Ahfir Ahmed Hammadi Abdellah Alem HuaQing Wang Gilbert Le Bras Tariq Ouahbi Normandie University UNIHAVREUMR 6294 CNRSLOMC76600 Le HavreFrance GeM UMR 6183 CNRSUniuersite de NantesBP 42044606 Saint Nazaire CedexFrance

The effects of porous media grain size distribution on the transport and deposition of polydisperse suspended particles under different flow velocities were investigated. Selected Kaolinite particles （2-30 μm） and Fluorescein （dissolved tracer） were injected in the porous media by step input injection technique. Three sands filled columns were used： Fine sand, Coarse sand, and a third sand （Mixture） obtained by mixing the two last sands in equal weight proportion. The porous media performance on the particle removal was evaluated by analysing particles breakthrough curves, hydro-dispersive parameters determined using the analytical solution of convection-dispersion equation with a first order deposition kinetics, particles deposition profiles, and particle-size distribution of the recovered and the deposited particles. The deposition kinetics and the longitudinal hydrodynamic dispersion coefficients are controlled by the porous media grain size distribution. Mixture sand is more dispersive than Fine and Coarse sands. More the uniformity coefficient of the porous medium is large, higher is the filtration efficiency. At low velocities, porous media capture all sizes of suspended particles injected with larger ones mainly captured at the entrance. A high flow velocity carries the particles deeper into the porous media, producing more gradual changes in the deposition profile. The median diameter of the deposited particles at different depth increases with flow velocity. The large grain size distribution leads to build narrow pores enhancing the deposition of the particles by straining.

关键词： Suspended particlesPorous mediaGrain size distributionStructured heterogeneityStrainingParticle size distribution

First Report of a Successful development of Yam Hybrids(Dioscorea alata L.)from Lyophilized and Long-Term Stored Pollens

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Phyton-International Journal of Experimental Botany 2023年第10期92卷 2861-2874页

作者： Erick Malédon Elie Nudol Christophe Perrot Marie-Claire Gravillon Ronan Rivallan Denis Cornet Hâna Chair Komivi Dossa CIRAD UMR AGAP InstitutPetit BourgGuadeloupe97170France umr AGAP Institut Univ MontpellierCIRADINRAEInstitut AgroMontpellierF-34398France CIRAD UMR AGAP InstitutMontpellierF-34398France

Various biological constraints including erratic and asynchronous flowering between male and female plants hinder successful hybrid development and genetic gains in greater yam breeding ***,pollen storage has gained much attention to facilitate artificial pollinations and increase the genetic *** 4-year study aimed at developing a practical long-term pollen storage technique for the successful development of yam *** pollens were collected from two Dioscorea alata males,then lyophilized(two lyophilization treatments were applied),followed by storage at room temperature(24℃–25℃)for 12 ***,the lyophilized and stored pollens were tested for viability by crossing with four female *** results showed that lyophilization is effective for achieving viable pollens after 12 months of *** 1(48 h drying)showed higher pollen germination and fertility rates than Treatment 2(72 h drying).Although we observed a reduction in viability of lyophilized pollens after 12 months of storage,we generated hybrid seedlings with success rates from 12%to 21%compared to 21%–31%when using fresh *** testing based on molecular genotyping confirmed the hybrid status of the obtained seedlings,which grew well in a *** is a practical approach for a long-term storage of greater yam pollen *** protocol will positively impact yam breeding programs particularly in developing countries.

关键词： Yam freeze-drying pollen conservation genetic gain

A phase field model for snow crystal growth in three dimensions

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npj Computational Materials 2017年第1期3卷 350-356页

作者： Gilles Demange Helena Zapolsky Renaud Patte Marc Brunel GPM UMR CNRS 6643University of RouenSaint Etienne du Rouvray 76575France CORIA umr 6614 University of RouenSaintÉtienne du Rouvray 76575France

Snowflake growth provides a fascinating example of spontaneous pattern formation in *** to understand this phenomenon have led to important insights in non-equilibrium dynamics observed in various active scientific fields,ranging from pattern formation in physical and chemical systems,to self-assembly problems in ***,very few models currently succeed in reproducing the diversity of snowflake forms in three dimensions,and the link between model parameters and thermodynamic quantities is not ***,we report a modified phase field model that describes the subtlety of the ice vapour phase transition,through anisotropic water molecules attachment and condensation,surface diffusion,and strong anisotropic surface tension,that guarantee the anisotropy,faceting and dendritic growth of *** demonstrate that this model reproduces the growth dynamics of the most challenging morphologies of snowflakes from the Nakaya *** find that the growth dynamics of snow crystals matches the selection theory,consistently with previous experimental observations.

关键词： dimensions phase field

Prediction of Thermal Conductivity and Specific Heat of Native Maize Starch and Comparison with HMT Treated Starch

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Journal of Renewable Materials 2019年第6期7卷 535-546页

作者： Aklouche Leila Monteau Jean-Yves Rezzoug Sid-Ahmed Maugard Thierry Guihard Luc Cohendoz Stephane Maache-Rezzoug Zoulikha LaSIE UMR CNRS 7356University of La RochelleAvenue Michel Crépeau17042 La RochelleFrance GEPEA UMR CNRS 6144ONIRISRue de la Géraudière44322 NantesFrance LIENSs umr CNRS 7266 Universitéde La RochelleFrance

Specific heat(Cp)and effective thermal conductivity(λ)of native maize starch(NS)were measured by DSC and transient heat transfer method,respectively,at different moisture contents and *** dependency of temperature(T)and moisture content(W)on the two parameters were *** thermophysical properties of treated starch(TS)by four hydrothermal processes(RP-HMT,IV-HMT,DV-HMT and FV-HMT)were measured and compared to native *** treatments were performed at 3 bars(133°C)for 10 *** Cp andλmeasurements,moisture content varied for NS from 5 to 21.5%*** from 8.8 to 25%d.b.,respectively,and was fixed at 6%*** *** models were developed to specific heat and effective thermal conductivity,using a multiple regression algorithm with subsequent statistical *** proposed models for NS based on T and W predict Cp andλwith a mean absolute error of 3.5%and 1.3%,*** differences in specific heat were observed between TS and *** a temperature range of 40 to 160°C,Cp values varied from 1.964 to 2.699 for NS and 1.380 to 2.085(J.g-1.°C-1)for *** contrast,the conductivity of NS was almost identical to that of treated starch by FV-HMT,followed in an increasing order by those treated by DV-HMT,RP-HMT,and IV-HM processes.

关键词： Starch HMT treatment specific heat effective thermal conductivity

Convex Variational Formulation with Smooth Coupling for Multicomponent Signal Decomposition and Recovery

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Numerical Mathematics(Theory,Methods and Applications) 2009年第4期2卷 485-508页

作者： Luis M.Briceo-Arias Patrick L.Combettes UPMC Universite Paris 06 Laboratoire Jacques-Louis Lions-UMR 7598 and Equipe Combinatoire et Optimisation-UMR 7090 UPMC Universite Paris 06 Laboratoire Jacques-Louis Lions-UMR 7598

A convex variational formulation is proposed to solve multicomponent signal processing problems in Hilbert *** cost function consists of a separable term, in which each component is modeled through its own potential,and of a coupling term, in which constraints on linear transformations of the components are penalized with smooth *** algorithm with guaranteed weak convergence to a solution to the problem is *** multicomponent signal decomposition and recovery applications are discussed.

关键词： Convex optimization denoising image restoration proximal algorithm signal decom-position signal recovery

Territorial Accessibility and Decision-Making Structure Related to Debris Flow Impacts on Roads in the French Alps

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International Journal of Disaster Risk Science 2016年第2期7卷 186-197页

作者： Marina Utasse Vincent Jomelli Delphine Grancher Frederic Leone Daniel Brunstein Clement Virmoux umr LGP:Laboratoire de Géographie Physique Université Paris 1 Panthéon-Sorbonne/8591 CNRS umr GRED:Gouvernance Risque EnvironnementDéveloppement Université Montpellier/IRD

The Alps are highly impacted by debris flows that cause major problems for companies and transport networks located in the valley bottoms. One such event occurred in the Rif Blanc catchment and affected the road network in the French Alps, as well as adjacent areas across the Italian border, for several days in June 2012. This article presents two independent approaches to vulnerability assessment. Based on investigations conducted during a survey of local authorities following the event, we compared theoretical risk management and real crisis management in terms of decision making and modes of intervention. Functional vulnerability and territorial consequences were analyzed using a best travel time model of accessibility. We show that a bottom-up approach is practiced in case of actual management planning with a central coordination of general council. Conversely theoretical crisis management shows prefect as the key actor supported by several other state institutions. Our analysis also revealed that a debris flow event with a local impact on the road network has territorial consequences at a regional scale. This study contributes to the discussion about how to minimize the vulnerability of alpine transport networks prone to debris flows. Our results could serve as a decision support tool for public authorities.

关键词： Crisis management Debris flows French Alps Road network vulnerability