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Theoretical & Applied Mechanics Letters 2022年第3期12卷 145-155页

作者： jean Pierre Pascal Pascal Coding Rue d’ErquyPleneuf-Val-Andre F-22370France

Present study provides a simple analytical formula,the“Klingel-like formula”or“Pascal’s Formula”that can be used as a reference to test some results of existing railway codes and specifically those using rigid *** develops properly the 3D Newton-Euler equations governing the 6 degrees of freedom(DoF)of unsuspended loaded wheelsets in case of zero wheel-rail friction and constant ***,by solving numerically these equations,we got pendulum like harmonic oscillations of which the calculated angular frequency is used for assessing the accuracy of the proposed formula so that it can in turn be used as a fast practical target for testing multi-body system(MBS)railway *** to the harmonic property of these pendulum-like oscillations,the squareω2 of their angular frequency can be made in the form of a ratio K/M where K depends on the wheelset geometry and load and M on its *** on K and M are useful to understand wheelsets *** analytical formula is derived from the first order writing of full trigonometric Newton-Euler equations by setting zero elastic wheel-rail penetration and by assuming small *** trigonometric equations are numerically solved to assess that the formula providesω2 inside a 1%accuracy for usual wheelsets *** decreasing the conicity down to 1×10^(−4) rad,the relative formula accuracy is under 3×10^(−5).In order to test the formula reliability for rigid contact formulations,the stiffness of elastic contacts can be increased up to practical rigidity(Hertz stiffness×1000).

关键词： Unsuspended wheelsets Klingel formula Rigid contact Harmonic oscillation Multi body system railway codes Code validation

Joint Loading Estimation Method for Horse Forelimb High Jerk Locomotion:Jumping

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Journal of Bionic Engineering 2019年第4期16卷 674-685页

作者： Joanne Becker Mermoz Emmanuel Linares jean-Marc Airbus Helicopters Aeroport de Marseille ProvenceMarignane 13700France Aix Marseille Univ CNRSISMInst Movement SciMarseille 13009France

Maximal local loads in animal joints are necessary to design bio-inspired mechanical *** studies presented methods to determine joint reaction forces in humans and ***,many of these methods are invasive,and no work has been published yet about the joint reaction forces in the horse forelimb during ***-invasive methods to measure the kinematics and ground reaction force of a horse forelimb were used in this work.A musculoskeletal model of horse forelimb was built with mechanical methods for the estimation of joint reaction *** entire forelimb was reconstructed by scanning real bones geometry with a 3D optical scanner and modeling all the muscles on a Computer Assisted Design(CAD)*** model dynamics were simulated with OpenSim in order to estimate the joint *** study allows knowing an order of magnitude of the loads at the joints at jumping in order to determine latter the maximal joint contact loading values that will be a key at designing bio-inspired joints for mechanical assemblies.

关键词： joint loading jumping kinematics modelling OpenSim

Continuous frequency and phase spectrograms: a study of their 2D and 3D capabilities and application to musical signal analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 199-206页

作者： Laurent NAVARRO Guy COURBEBAISSE jean-Charles PINOLI Ecole Nationale Supérieure des Mines de Saint-Etienne Centre Ingénierie et Santé (CIS) and LPMG UMR 5148 CNRS 158 cours Fauriel 42023 Saint-Etienne cedex 2 France Medical Imaging Research Center (CREATIS-LRMN) UMR 5220 CNRS U630 INSERM Université Lyon 1 INSA Lyon Bat. Blaise Pascal 7 Av. Jean Capelle 69621 Villeurbanne France

A new lighting and enlargement on phase spectrogram （PS） and frequency spectrogram （FS） is presented in this paper. These representations result from the coupling of power spectrogram and short time Fourier transform （STFT）. The main contribution is the construction of the 3D phase spectrogram （3DPS） and the 3D frequency spectrogram （3DFS）. These new tools allow such specific test signals as small slope linear chirp, phase jump case of musical signal analysis is reported. The main objective is to and small frequency jump to be analyzed. An application detect small frequency and phase variations in order to characterize each type of sound attack without losing the amplitude information given by power spectrogram

关键词： Frequency spectrogram (FS) Phase spectrogram (PS) Time-frequency representations Musical signals

Modelling and simulation of flight control electromechanical actuators with special focus on model architecting, multidisciplinary effects and power flows

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Chinese Journal of Aeronautics 2017年第1期30卷 47-65页

作者： Fu Jian jean-Charles Maré Fu Yongling School of Mechanical Engineering and Automation Beihang University Beijing 100083 China Institut Clement Ader (CNRS UMR 5312) INSA-Toulouse Toulouse 31077 France

In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortunately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now available on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling,thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power network pollution analysis and fault response.

关键词： Bond Graph Electro-hydrostatic actuator Electromechanical actuator More electric aircraft Modelling Power-by-wire Power loss Simulation

Ontogeny of Drosophila melanogaster female sex-appeal and cuticular hydrocarbons

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Integrative Zoology 2010年第3期5卷 272-282页

作者： Marisa ARIENTI Claude ANTONY Claude WICKER-THOMAS jean-Paul DELBECQUE jean-Marc JALLON University of Paris South 11 Center of Neurosciences of Paris SouthOrsayFrance Department of Biology Autonoma Metropolitan University-XochimilcoMexico DFMexico EMBL HeidelbergGermany LEGS CNRSGif sur YvetteFrance University of Bordeaux 1 Center of Integrative and Cognitive NeurosciencesTalenceFrance

The chemical communication system in Drosophila melanogaster Meigen,1830 plays a major role in courtship and consists of the male-specific cis-Vaccenyl acetate and sex-specific contact pheromones,cuticular hydrocarbons(CHC),which build up during ontogeny(first 4 days).They replace longer CHCs,common to both sexes and present only after the imaginal eclosion.A detailed quantitative description of the evolution of cuticular unsaturated hydrocarbons with age is presented here for males and females of different *** strains,which have been bred in well controlled *** appear in both sexes at around 12 h,before female *** present paper argues that this is likely linked to the switching on of a new set of ***,which is more abundant in females than in males during this critical period,might control this *** behavioral studies show that whereas female of all ages trigger early mature male courtship steps like wing vibration,only females older than 1 day trigger late courtship steps like attempted *** supports the hypothesis that late male courtship steps might be triggered by the CHCs,which build up after this age,especially female-specific(Z,Z)-7,11-and(Z,Z)-5,9-dienes.

关键词： contact pheromones Drosophila melanogaster ecdysone control ontogeny sex differences

ON MAXWELL EQUATIONS WITH THE TRANSPARENT BOUNDARY CONDITION

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Journal of Computational Mathematics 2008年第3期26卷 284-296页

作者： Zhiming Chen jean-Claude Nédélec LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Centre de Mathématiques Appliquées Ecole Polytechnique 91228 Palaiseau Cedex France

In this paper we show the well-posedness and stability of the Maxwell scattering problem with the transparent boundary condition. The proof depends on the well-posedness of the time-harmonic Maxwell scattering problem... 详细信息

关键词： Electromagnetic scattering Well-posedness Stability

Relation between silico-aluminous fly ash and its coal of origin

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Particuology 2008年第2期6卷 85-92页

作者： jean-Charles Benezet Pierre Adamiec Ali Benhassaine Ecole des Mines d'Alès 6 Avenue de Clavieres30319 ALES CedexFrance

Fly ashes are typical complex solids which incorporate at the same time intrinsic properties derived from the layers （various mineralogical and dimensional spectra） and major transformations generated during prior processing. To use fly ashes in various applications, it is necessary to characterise them completely. The first research to date carried out on silico-aluminous fly ashes in order to characterise them physically, morphologically, chemically and mineralogically, resulted in the recognition that they are relatively simple materials. In the present study, a silico-aluminous fly ash coming from the power station of Albi （France） was selected. Heat treatment at 450 and 1200℃ together with coal simulated the treatment undergone by coal in the power station in order to mimic real coal residue. In conclusion, the diversity of the particles contained in fly ash could only be exolained by the relation existing between the fly ash and its coal of origin.

关键词： Fly ash Selection Thermal treatment

Towards a simple and safe Objective Caml compiling framework for the synchronous language SIGNAL

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Frontiers of Computer Science 2019年第4期13卷 715-734页

作者： Zhibin YANG jean-Paul BODEVEIX Mamoun FILALI School of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 211106 China State Key Laboratory of Software Development Environment Beijing 100191 China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 211106 China IRIT-CNRS Universite de Toulouse Toulouse 31062 France

This paper presents a simple and safe compiler, called MinSIGNAL, from a subset of the synchronous dataflow language SIGNAL to C, as well as its existing en? hancements. The compiler follows a modular architecture, and can be seen as a sequence of source-to-source transformations applied to an intermediate representation which is named Synchronous Clocked Guarded Actions (S-CGA) and translation to sequential imperative code. Objective Caml (OCaml) is used for the implementation of MinSIGNAL. As a modem functional language, OCaml is adapted to symbolic computation and so, particularly suitable for compiler design and implementation of formal analysis tools. In particular, the safety of its type checking allows to skip some verification that would be mandatory with other languages. Additionally, this work is a basis for the formal verification of the compilation of SIGNAL with a theorem prover such as Coq.

关键词： synchronous languages SIGNAL Synchronous Clocked Guarded Actions (S-CGA) Objective Caml functional programming

Pozzolanic reactivity of silico-aluminous fly ash

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Particuology 2008年第2期6卷 93-98页

作者： Pierre Adamiec jean-Charles Benezet Ali Benhassaine Ecole des Mines d'Alès 6 Avenue de Clavières30319 ALES CedexFrance

For some years it has been possible to control the particle size of fly ashes, by-products of thermal power stations. Incorporating these very fine particles （obtained by grinding and/or pneumatic selection） improves the physical-mechanical characteristics of mortars and concretes. In this study, we measured the lime consumption of the various fractions （granulometric and densimetric） and identified by X-ray diffraction the neoformed phases by the pozzolanic reaction, to show that it is not sufficient to simply define the pozzolanicity of products based on lime consumption since it does not take into account the nature of the phases formed. The size of the particles used in the test samples also has a determining effect on the quantity of lime consumed. Before comparing results, it is necessary to ensure that the size of the particles （of the global ash and its constituents） be the same. Two distinct neoformed ohases appear： CSH in the largest granular fractions （d〉 40 μm） and C3AH6 in the smaller fractions.

关键词： Fly ash Pozzolanic reaction Particle size

Characterization of Particle Emissions of Turbocharged Direct Injection Gasoline Engine in Transients and Hot Start Conditions

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Journal of Thermal Science 2021年第6期30卷 2056-2070页

作者： Vincent BERTHOME David CHALET jean-François HETET Ecole Centrale de Nantes LHEEA Lab.(ECN/CNRS)Nantes 44300France

Reducing pollutant emissions,particularly soot particles emitted by internal combustion engines,is a major challenge for car *** this paper,the experimental setup is a turbocharged three-cylinders gasoline direct injection engine installed on a HORIBA dynamic test driven by a HORIBA STARS *** particle-measuring device is a Pegasor Particles Sensor that measures the current carried by previously electrically charged *** hot engine stabilized tests,with lambda parameter lower or equal to one,have very low emission levels,unlike dynamic *** a consequence,the present paper deals with experiments in transient *** diesel engine,cycle tests show that particulate emissions vary *** understand the phenomenon,a simple transient was created and reproduced a hundred times in order to obtain enough data to analyze and compare these different *** transient starts from idle to reach the speed of 2000 r/min and 60 N·m in 5 *** reach this point,it is necessary to stay in full load for about 3 *** maximum deviations of particles reaches 85%with the standard deviationσ=18%.The cylinder pressure sensor shows significant variations at the very beginning of each transient,i.e.,during the first 500 *** kind of result was observed for Worldwide harmonized Light vehicles Test Cycles(WLTC)with a maximum deviations of particles reaching 75%withσ=30%,on Real Drive Emissions Cycle(RDE)with a maximum deviations of particles reaching 45%withσ=22%and for a 300 s Mini-Cycle with a maximum deviations of particles reaching 70%withσ=17%.The Mini-cycle is made up of the five largest accelerations of the WLTP cycle.A complete analysis highlights the importance of filling the first engine *** depends on the opening speed of the throttle,the position of the crankshaft at the beginning of the transient,and the acceleration of the first ***,the NO_(x) sensor shows very slight variations between each *** a consequence,i

关键词： particles gasoline engine cycle-to-cycle variations transients oil consumption