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Nuclear Science and Techniques 2022年第3期33卷 113-125页

作者： Xiao-Wen Zhu Claude Marchand Olivier Piquet michel Desmons IRFU CEAUniversite´Paris-Saclay91191 Gif-sur-YvetteFrance

Compact accelerator-based neutron source facilities are garnering attention and play an important and expanding role in material and engineering sciences,as well as in neutron science education and *** are produced by bombarding a low-energy proton beam onto a beryllium or lithium *** such an acceleratorbased neutron source,a radio frequency quadrupole(RFQ)is usually utilized to accelerate a high-intensity proton beam to a few *** study mainly covers the highfrequency structure design optimizations of a 4-vane RFQ with pi-mode stabilizer loops(PISLs)and its RF stability analysis.A 176 MHz RFQ accelerator is designed to operate at a 10%duty factor and could accelerate an80 mA proton beam from 65 keV to 2.5 MeV within a length of 5.3 *** adoption of PISLs ensures high RF stability,eases the operation of the accelerator,and implies less stringent alignment and machining tolerances.

关键词： Accelerator-based neutron source 4-vane RFQ accelerator Pi-mode stabilizer loops Perturbative analysis Electromagnetic design Multipacting simulation

Long Division Unites or Long Union Divides:a Model for Social Network Evolution

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Chinese Physics Letters 2013年第3期30卷 206-210页

作者： JIANG Jian WANG Ru Pezeril michel Wang Qiuping Alexandre Complexity Science Center and Institute of Particle Physics Huazhong Normal UniversityWuhan 430079 Institut Supérieur des Matériaux et Mécaniques Avancés 44 Avenue F.A.Bartholdi72000 Le MansFrance IMMM UMR 6283Universitédu MaineAve.O.Messaen72085 Le MansFrance College of Mathematics and Computer Science of Wuhan Textile University Wuhan 430200 College of Infromation Science and Engineering Huajiao UniversityQuanzhou 362021

A remarkable phenomenon in the time evolution of many networks such as cultural,political,national and economic systems is the recurrent transition between the states of union and the division of *** propose a phenomenological modeling,inspired by the maxim"long union divides and long division unites"to investigate the evolutionary characters of these networks composed of the entities whose behaviors are dominated by these two *** nodes are endowed with quantities such as identity,ingredient,richness(power),openness(connections),age,distance,and interaction,which determine collectively the evolution in a probabilistic *** on a tunable parameter,the time evolution of this model is mainly an alternative domination of union or division state,with a possible state of final union dominated by one single node.

关键词： union collective quantities

Diffusion weighted MRI and tractography for evaluating peripheral nerve degeneration and regeneration

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Neural Regeneration Research 2014年第24期9卷 2122-2124页

作者： Neil G.Simon michel Kliot Prince of Wales Clinical School University of New South Wales Central Clinical School The University of Sydney Department of Neurological Surgery Northwestern Feinberg School of Medicine

Accurately documenting and quantifying peripheral nerve axonal degeneration and regeneration is critically important for clinical research in peripheral nerve disorders such as nerve trauma, peripheral neuropathy and amyotrophic lateral sclerosis （ALS）. Current strategies include clinical assessments and neurophysiological studies （including nerve conduction studies and electromyography （EMG））. However, the information provided by these strategies is limited in a number of ways.

关键词： DTI MRI Figure

Asymptotic Analysis in a Gas-Solid Combustion Model with Pattern Formation

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Chinese Annals of Mathematics,Series B 2013年第1期34卷 65-88页

作者： Claude-michel BRAUNER Lina HU Luca LORENZI School of Mathematical Sciences Xiamen University Institut de Mathématiques de Bordeaux Université de Bordeaux Dipartimento di Matematica e Informatica Università degli Studi di ParmaParco Area delle Scienze 53/A

The authors consider a free interface problem which stems from a gas-solid model in combustion with pattern formation. A third-order, fully nonlinear, self-consistent equation for the flame front is derived. Asymptotic methods reveal that the interface approaches a solution to the Kuramoto-Sivashinsky equation. Numerical results which illustrate the dynamics are presented.

关键词： Asymptotics Free interface Kuramoto-Sivashinsky equation Pseudo-differential operator Spectral method

Toward Global Complex Systems Control - The Autonomous Intelligence Challenge

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Journal of Autonomous Intelligence 2019年第1期2卷 11-29页

作者： michel Cotsaftis ECE Paris School of Engineering ParisFrance

Complex systems are the emerging new scientific frontier with modern technology advance and new parametric domains study in natural *** important challenge is,contrary to classical systems studied so far,the great difficulty in predicting their future behaviour from initial time because,by their very structure,interactions strength between system components is shielding completely their specific individual *** of clear existence of strict laws complex systems are obeying like classical systems,it is however possible today to develop methods allowing to handle dynamical properties of such systems and to master their *** the methods should be imperatively adapted to representing system self organization when becoming *** rests upon the new paradigm of passing from classical trajectory space to more abstract trajectory manifolds associated to natural system invariants characterizing complex system *** methods are basically of qualitative nature,independent of system state space dimension and,because of its generic impreciseness,privileging robustness to compensate for not well known system parameters and functional *** points toward the importance of control approach for complex system study in adequate function spaces,the more as for industrial applications there is now evidence that transforming a complicated man made system into a complex one is extremely beneficial for overall performance *** this last step requires larger intelligence delegation to the system requiring more autonomy for exploiting its full potential.A well-defined,meaningful and explicit control law should be set by using equivalence classes within which system dynamics are forced to stay,so that a complex system described in very general terms can behave in a prescribed way for fixed system parameters *** the line traced by Nature for living creatures,the delegation is expressed at lower level by a change from regu

关键词： Complex Systems Autonomous Intelligence System Components Bounding System Dynamics

Considerations for the Conduction and Interpretation of FAIRness Evaluations

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Data Intelligence 2020年第1期2卷 285-292页

作者： Ricardo de Miranda Azevedo michel Dumontier Institute of Data Science Maastricht UniversityUniversiteitssingel 60Maastricht 6229 ERThe Netherlands

The FAIR principles were received with broad acceptance in several scientific ***,there is still some degree of uncertainty on how they should be *** self-report questionnaires have been proposed to assess the implementation of the FAIR ***,the FAIRmetrics group released 14,general-purpose maturity for representing ***,these metrics were conducted as open-answer ***,these metrics have been implemented into a software that can automatically harvest metadata from metadata providers and generate a principle-specific FAIRness *** so many different approaches for FAIRness evaluations,we believe that further clarification on their limitations and advantages,as well as on their interpretation and interplay should be considered.

关键词： FAIR metrics FAIR principles FAIR data FAIRness Implementation Maturity indicators Scientific community

Periodic Solutions of Evolution Variational Inequalities—a Method of Guiding Functions

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Chinese Annals of Mathematics,Series B 2009年第3期30卷 261-272页

作者： Samir ADLY Daniel GOELEVEN michel THRA Département de Math'ematiques et Informatique Laboratoire XLIM(Unité Mixte 6172 du CNRS)Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. Laboratoire d' Informatique et de Mathématiques Université de La Réunion97400 Saint-DenisFrance.

This paper focuses on a part of the presentation given by the third author at the Shanghai Forum on Industrial and Applied Mathematics(Shanghai 2006).It is related to the existence of a periodic solution of evolution ... 详细信息

关键词： Variational inequality Differential inclusion Topological degree Guiding function Periodic solution

Existence Results for a Class of Periodic Evolution Variational Inequalities

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Chinese Annals of Mathematics,Series B 2007年第6期28卷 629-650页

作者： Samir ADLY Daniel GOELEVEN michel THRA DMI-XLIM UMR-CNRS 6172Université de Limoges123 Avenue A.Thomas87060 Limoges CedexFrance. IREMIA Université de La Réunion97400 Saint-DenisFrance.

In this paper, using the Brouwer topological degree, the authors prove an existence result for finite variational inequalities. This approach is also used to obtain the existence of periodic solutions for a class of e... 详细信息

关键词： Variational inequalities Differential inclusions Topological degree Guiding functions Periodic solutions

Zircon U-Pb and Lu-Hf isotope constraints on Archean crustal evolution in Southeastern Guyana Shield

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Geoscience Frontiers 2019年第4期10卷 1477-1506页

作者： Joao Marinho Milhomem Neto Jean-michel Lafon Programa de Pos-graduacao em Geologia e Geoquimica-PPGG Instituto de Geociencias-IGUniversidade Federal do Para-UFPA66075-110BelemParaBrazil Laboratório de Geologia Isotópica-Pará-Iso IG-UFPA66075-110BelémParáBrazil

The southeastern Guyana Shield,northeast Amazonian Craton,in the north of Brazil,is part of a widespread orogenic belt developed during the Transamazonian orogenic cycle(2.26-1.95 Ga)that includes a large Archean continental landmass strongly reworked during the Transamazonian orogeny,named Amapa *** consists mainly of a high-grade metamorphic granulitic-migmatitic-gneiss complex,of Meso-to Neoarchean age and Rhyacian granitoids and supracrustal *** the first time,coupled U-Pb and Lu-Hf isotope data were obtained on zircon by LA-ICP-MS from five tectono-stratigraphic units of the Archean basement and one Paleoproterozoic intrusive rock,in order to investigate the main episodes of crustal growth and ***-rock Sm-Nd isotope data were compared to the zircon Lu-Hf *** main magmatic episodes were defined by U-Pb zircon dating,two in the Mesoarchean(~3.19 Ga and 2.85 Ga)and one in the Neoarchean(~2.69-2.65 Ga).SubchondriticεHf(t)values obtained for almost all investigated units indicate that crustal reworking processes were predominant during the formation of rocks that today make up the Amapa ***-TDMC model ages,ranging from2.99 Ga to 3.97 Ga,indicate that at least two important periods of mantle extraction and continental crust formation occurred during the Archean in southeastern Guyana Shield,an older one in the Eoarchean(~4.0 Ga)and a younger one in the Mesoarchean(~3.0-3.1 Ga).The latter is recognized as an important period of crustal accretion *** recognition of an Eoarchean episode to the southeastern most part of the Guyana Shield is unprecedented and was not recorded by whole-rock Sm-Nd data,which were restricted to the Meso-Paleoarchean(2.83 Ga to 3.51 Ga).This finding reveals t hat continental crust generation in the Amazonian Craton began at least 500 Ma earlier than previously suggested by the SmNd systematics.

关键词： U-Pb-Lu-Hf isotopes Zircon Archean crustal evolution Southeastern Guyana Shield Amazonian Craton

Convergence to a Single Wave in the Fisher-KPP Equation(Dedicated to Haim Brezis,with admiration and respect)

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Chinese Annals of Mathematics,Series B 2017年第2期38卷 629-646页

作者： James NOLEN Jean-michel ROQUEJOFFRE Lenya RYZHIK Department of Mathematics Duke UniversityDurhamNC 27708USA Institut de Mathématiques(UMR CNRS 5219) Université Paul Sabatier118 route de Narbonne31062 Toulouse cedexFraxlce Department of Mathematics Stanford UniversityStanford CA94305USA.

The authors study the large time asymptotics of a solution of the Fisher-KPP reaction-diffusion equation, with an initial condition that is a compact perturbation of a step function. A well-known result of Bramson states that, in the reference frame moving as 2t-(3/2 )log t+x∞, the solution of the equation converges as t → +∞ to a translate of the traveling wave corresponding to the minimal speed c_* = 2. The constant x∞ depends on the initial condition u(0, x). The proof is elaborate, and based on probabilistic *** purpose of this paper is to provide a simple proof based on PDE arguments.

关键词： Traveling waves, KPP, Front propagation, Asymptotic analysis,Reaction-diffusion