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Chinese Journal of Aeronautics 2024年第3期37卷 92-103页

作者： Valerian PALANQUE Jason POTHIN Vale′rie POMMIER-budinger marc budinger Institut Clement Ader University of ToulouseINSAISAE-SUPAEROMINES ALBIUPSCNRSToulouse 31055France ISAE-SUPAERO University of Toulouse10 Avenue Edouard BelinToulouse 31055France

This paper proposes a numerical method to analyze the ice protection capability and predict the power requirements of a piezoelectric resonant de-icing *** method is based on a coupled electro-mechanical finite element analysis which enables the fast computation of the modes of resonance of interest to de-ice curved surfaces and the estimation of the input voltage and current required for a given configuration(defined by its mode,actuator location,ice deposit,etc.).Eventually,the electric power to be supplied can be also *** method is applied to a NACA 0024 leading edge equipped with piezoelectric ***,two extension modes are analyzed and compared with respect to their efficiency and power ***,tests are carried out in an icing tunnel to verify the effectiveness of the piezoelectric ice protection system and the predictions of the maximal required *** system allows de-icing the leading edge in less than 2 s for a glaze ice deposit.

关键词： Ice protection system Piezoelectric Resonance mode Ice fracture Leading edge de-icing

Piezoelectric resonant ice protection systems-Part 2/2:Evaluation of benefits at aircraft level

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Chinese Journal of Aeronautics 2024年第6期37卷 50-63页

作者： Valerian PALANQUE Thomas PLANES Pommier-budinger VALERIE budinger marc Delbecq SCOTT Institut Clement Ader(ICA) INSAISAE-SUPAEROMINES ALBIUPSCNRSUniversity of Toulouse31400 ToulouseFrance Federation ENAC ISAE-SUPAERO ONERA University of Toulouse31400 ToulouseFrance

Piezoelectric resonant de-icing systems are attracting great *** paper aims to assess the implementation of these systems at the aircraft *** article begins with the model to compute the power requirement of a piezoelectric resonant de-icing system sized from the prototype detailed in Part 1/2 of this *** the mass,drag,and fuel consumption of this system and the subcomponents needed for its implementation are *** features of a piezoelectric resonant de-icing system are finally computed for aircraft similar to Airbus A320 aircraft and aircraft of different categories(Boeing 787,ATR 72 and TBM 900)and compared with the existing thermal and mechanical ice protection systems.A sensitivity analysis of the main key sizing parameters of the piezoelectric de-icing system is also performed to identify the main axes of improvement for this *** study shows the potential of such ice protection *** particular,for the realistic input parameters chosen in this work,the electro-mechanical solution can provide a 54% reduction in terms of mass and a 92% reduction in terms of power consumption for an A320 aircraft architecture,leading to a 74% decrease in the associated fuel consumption compared to the actual air bleed system.

关键词： Ice protection system De-icing Piezoelectric Electro-mechanical system Power Fuel consumption

Bound and Resonating Multiquark Configurations

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Chinese Physics Letters 2024年第8期41卷 8-12页

作者： Jean-marc Richard Institut de Physique des 2 Infinis de Lyon Université Claude Bernard(Lyon 1) CNRS-IN2P34 rue Enrico Fermi69622 VilleurbanneFrance

We review the predictions of quark models for multiquark configurations that are bound or resonant states,and compare different methods for estimating the properties of resonances.

关键词： quark Configuration resonant

Fibre optic distributed scattering sensing system:perspectives and challenges for high performance applications

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仪器仪表学报 2007年第8期28卷 1345-1352页

作者： marc Niklès Omnisens SA Riond-Bosson 3CH-1110 MorgesSwitzerland

As fiber optic distributed scattering sensing systems are providing innovative solutions for the monitoring of large structures,the comparison of different techniques and solutions is difficult because of the lack of standardized specifications and the difficulty associated to the characterization of such *** article presents a tentative definition of performance specifications and qualification procedures applicable to fiber optic distributed sensing systems aiming at providing clear guidelines for their design,specifications,qualification,application and selection.

关键词：纤维光学传感器分布式散射传感系统发展前景应用布里渊散射空间分辨率温度

Computational modelling of gas–liquid–solid multiphase free surface flow with and without evaporation

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Particuology 2024年第7期90卷 218-235页

作者： Huihuang Xia marc Kamlah Institute for Applied Materials(IAM) Karlsruhe Institute of Technology(KIT)Hermann-von Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany

Gas–liquid–solid multiphase systems are ubiquitous in engineering applications,*** printing,spray drying and *** a numerical framework for modelling these multiphase systems is of great *** improved,resolved computational fluid dynamics-discrete element method(CFD-DEM)framework is developed to model the multiphase free surface flow with and without *** improved capillary force model is developed to compute the capillary interactions for partially floating particles at a free *** well-known benchmark cases,namely drag coefficient calculation,the single sphere settling,and drafting-kissing-tumbling of two particles are conducted to validate the resolved CFD-DEM *** turns out that the resolved CFD-DEM model developed in this paper can accurately calculate the fluid–solid interactions and predict the trajectory of solid particles interacting with the liquid *** demonstrations,namely two particles moving along a free surface when the liquid phase evaporates,and particle transport and accumulations inside an evaporating sessile droplet show the performance of the resolved model.

关键词： Capillary force Discrete element method Liquid bridge Particle transport Resolved CFD-DEM Volume of fluid

NON SPURIOUS SPECTRAL-LIKE ELEMENT METHODS FOR MAXWELL'S EQUATIONS

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Journal of Computational Mathematics 2007年第3期25卷 282-304页

作者： Gary Cohen marc Duruflé INRIA Domaine de VoluceauRocquencourt-BP 10578153 Le Chesnay CedexFrance

In this paper, we give the state of the art for the so called “mixed spectral elements” for Maxwell＇s equations. Several families of elements, such as edge elements and discon-tinuous Galerkin methods （DGM） are presented and discussed. In particular, we show the need of introducing some numerical dissipation terms to avoid spurious modes in these methods. Such terms are classical for DGM but their use for edge element methods is novel approach described in this paper. Finally, numerical experiments show the fast and low-cost character of these elements.

关键词： Maxwell's equations Discontinuous Galerkin methods Edge elements Masslumping.

Precision Measurement of Complex Optics Using a Scanning‑Point Multiwavelength Interferometer Operating in the Visible Domain

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Nanomanufacturing and Metrology 2023年第2期6卷 19-26页

作者： marc Wendel Ametek GmbH/BU Taylor Hobson Rudolf-Diesel-Str.1664331 WeiterstadtGermany

The growing demands of optical systems have led to increasingly complex aspheres and *** this paper,an established measurement system in asphere production,which is also a promising approach in high-precision freeform metrology,is *** is based on a scanning-point multiwavelength interferometer *** scanning principle enables great fexibility,reduces setup time and costs,and has almost no limitations in spherical *** to the absolute measurement capability,the utilized multiwavelength approach is benefcial for segmented,annular,and discrete surfaces,which are common designs of modern applications’optical *** metrology system enables measurements on a nanometer scale on a great variety of apertures—from 1 to 1000 ***,a new short-coherence multiwavelength interferometer operating in the visible domain has been *** enables the high-precision measurement on silicon-coated surfaces,which can be found in space applications and are also commonly used for extreme-ultraviolet(EUV)lithographic setups,which will be used as an example throughout this *** to the large absolute measurement capability,applied grating structures for suppressing infrared light in the EUV process can easily be *** paper summarizes the basic working principles of the proposed metrology system,explains the special requirements for diferent felds of application,highlights the capabilities of the visible multiwavelength approach,and shows the measurement results.

关键词： Multiwavelength interferometer Scanning-point sensor Metrology Short coherence interferometry

An integrated hard- and soft-ware triboelectrochemical test rig for tribocorrosion experiments

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Friction 2015年第3期3卷 256-258页

作者： marc BELLANTONIO TRIBOtechnic 4 rue ValitonF-92110 ClichyFrance

Tribocorrosion is a degradation mechanism resulting from the interaction of mechanical(wear)and chemical(corrosion)*** interaction leads to surface damage that does not correspond to the simple sum of wear and corrosion taken *** tribocorrosion of material pairings thus requires the capability not only to control the mechanical and chemical test parameters but also to identify the relative contribution of corrosion and wear in the overall material *** paper describes a novel laboratory tribocorrosion test set-up combining in one experiment the control of mechanical input(load,velocity,and frequency)and output(friction and wear)parameters as well as the control of corrosion phenomena through a series of dedicated electrochemical methods(open circuit,potentiostatic and potentiodynamic measurements).The possibilities offered by this set-up are illustrated by selected case studies.

关键词： tribocorrosion friction and corrosion tribotechnic

Congenital left ventricular aneurysms and diverticula： an entity in search of an identity

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Journal of Geriatric Cardiology 2017年第12期14卷 750-762页

作者： marc-Alexander Ohlow Heart Center Department of Cardiology Zentralklinik Bad Berka Germany

Congenital left ventricular aneurysm or diverticulum are rare cardiac malformations described in 809 cases since the first description in 1816, being associated with other cardiac, vascular or thoraco-abdominal abnormalities in about 70%. It appears to be a developmental anomaly, starting in the 4th embryonic week. In an experimental study, targeted knockdown of cardiac troponin T in the chick was performed at day 3, after the heart tube has formed. Morpholino treatment of gene TNNT2 at this stage led to the development of left ventricular diver- ticula （LVD） in the primitive left ventricular wall. Diagnosis of left ventricular aneurysms （LVA）/LVD can be made after exclusion of coro- nary artery disease, local or systemic inflammation or traumatic causes as well as cardiomyopathies. Clinically, most of LVA and LVD are asymptomatic or may cause systemic embolization, congestive heart failure, valvular regurgitation, ventricular wall rupture, ventricular tachycardia or sudden cardiac death. Diagnosis is established by imaging studies （echocardiography, magnetic resonance imaging or left ventricular angiography） visualizing the structural changes and accompanying abnormalities. Mode of treatment has to be individually tai- lored and depends on clinical presentation, accompanying abnormalities and possible complications, options include surgical resection （espe- cially in symptomatic patients）, anticoagulation after systemic embolization, radiofrequency ablation or implantation of an implantable car- dioverter defibrillator （ICD） in case of symptomatic ventricular tachycardias, and occasionally combined with class I- or III-antiarrhythmic drugs. Cardiac death occurs usually in childhood, is significantly more frequent in LVA patients and caused by congestive heart failure in most of the cases, whereas patients diagnosed with LVD died more frequently from rupture of the LVD.

关键词： Aneurysm Congenital Diverticulum Left ventricular Prognosis Therapy

Global significance of oxygen and carbon isotope compositions of pedogenic carbonates since the Cretaceous

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Geoscience Frontiers 2021年第4期12卷 34-45页

作者： marc Jolivet Philippe Boulvais Géosciences Rennes CNRSUniv RennesUMR 6118F-35000RennesFrance

Few global syntheses of oxygen and carbon isotope composition of pedogenic carbonates have been attempted,unlike marine *** carbonates represent in-situ indicators of the climate conditions prevailing on *** δ^(18)O and δ^(13)C values of pedogenic carbonates are controlled by local and global factors,many of them not affecting the marine carbonates largely used to probe global climate *** compile pedogenic oxygen and carbon isotopic data(N=12,167)fromCretaceous to Quaternary-aged paleosols to identify potential trends through time and tie them to possible controlling *** discrete events such as the Paleocene-Eocene Thermal Maximum are clearly evidenced,our analysis reveals an increasing complexity in the distribution of the δ^(18)O vs δ^(13)C values through the *** could be expected,the rise of C4 plants induces a shift towards higherδ13C values during the Neogene and *** also show that the increase in global hypsometry during the Neogene plays a major role in controlling the δ^(18)O and δ^(13)C values of pedogenic carbonates by increasing aridity downwind of orographic ***,during the Quaternary,an increase of 3‰in δ^(18)O values is recorded both by the pedogenic carbonates and the marine foraminifera suggesting that both indicators may be used to track global climate signal.

关键词： Global isotopic signal Cretaceous–Quaternary Pedogenic carbonates Topography