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Assessment of ship manoeuvrability by using a coupling between a nonlinear transient manoeuvring model and mathematical programming techniques

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Journal of Hydrodynamics 2013年第5期25卷 788-804页

作者： TRAN KHANH Toan OUAHSINE Abdellatif NACEUR Hakim EL WASSIFI Karima laboratoire Roberval Université de Technologie de Compiègne laboratoire LAMIH Université de Valenciennes Université Cadi Ayyad Faculté des Sciences et Techniques

In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming （MP） techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories.

关键词： ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming

Soil-atmosphere interaction in earth structures

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 35-49页

作者： Yujun Cui laboratoire Navier Ecole des Ponts ParisTechFrance

The soil-atmosphere interaction was investigated through laboratory testing,field monitoring and numerical *** the laboratory,the soil water evaporation mechanisms were studied using an environmental chamber equipped with a large number of sensors for controlling both the air parameters and soil *** sand and clay were *** case of sand,a dry layer could be formed during evaporation in the near surface zone where the suction corresponded to the residual volumetric water *** evaporative surface was situated at a depth where the soil temperature was the *** case of clay,soil cracking occurred,changing the evaporative surface from one-dimensional to three-dimensional *** suctionbased evaporation model was adapted to take these phenomena into account by adopting a function of dry layer evolution in the case of sand and by adopting a surface crack ratio and a retative humidity ratio in the case of *** the field,the volumetric water content,and the suction as well as the runoff were monitored for an embankment constructed with lime/cement treated *** appeared that using precipitation data only did not allow a correct description of the variations of volumetric water content and suction inside the soils,the consideration of water evaporation being *** was possible to use a correlation between precipiration and *** hydraulic conductivity was found to be a key parameter controlling the variations of volumetric water content and *** the numerical modelling,a fully coupled thermohydraulic model was developed,allowing analyzing the changes in temperature,volumetric water content and suction of soil,with the upper boundary conditions at the interface between soil and atmosphere determined using meteorological *** between simulations and measurements showed the performance of such numerical approach.

关键词： Environmental chamber Soil water evaporation Suction-based evaporation model Embankment Field monitoring Numerical modeling

Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology

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Chinese Physics Letters 2016年第5期33卷 144-148页

作者： Sara Benchikh Noureddine Mebarki Dalel Aberkane laboratoire de Physique Mathematique et Subatomique Mentouri University

Dynamical behaviors and stability properties of a flat space Friedmann-Robertson-Walker universe filled with pressureless dark matter and viscous dark energy are studied in the context of standard classical and loop quantum cosmology. Assuming that the dark energy has a constant bulk viscosity, it is found that the bulk viscosity effects influence only the quintessence model case leading to the existence of a viscous late time attractor solution of de- Sitter type, whereas the quantum geometry effects influence the phantom model case where the big rip singularity is removed. Moreover, our results of the Hubble parameter as a function of the redshift are in good agreement with the more recent data.

关键词： of on in Dynamical Study of a Constant Viscous Dark Energy Model in Classical and Loop Quantum Cosmology is that for been FRW

Determination of electrostatic parameters of a coumarin derivative compound C_(17)H_(13)NO_3 by x-ray and density functional theory

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Chinese Physics B 2015年第10期24卷 359-365页

作者： Youcef Megrouss Nadia Benhalima Rawia Bahoussi Nouredine Boukabcha Abdelkader Chouaih Fodil Hamzaoui laboratoire de Technologie et Proprietedu Solide(LTPS) University of Mostaganem

This work is devoted to the experimental determination of the electrostatic properties of the molecular 4-methyl-7-（salicylidene amino） coumarin（C17H13NC3） using high resolution x-ray diffraction data. The experimental results are compared with those obtained theoretically from calculation type ab initio. The experimental investigation is carried out using the molecular electron charge density distribution based on the multipolar model of Hansen and Coppens. However the theoretical calculations are conducted by using the molecular orbital B3 LYP method and the Hartree-Fock（HF） approximation with the basis set 6-31G（d,p） implemented in the Gaussian program. In addition to the structural analysis,the thermal agitation is also analyzed in terms of rigid blocks to ensure a better precision of the results. Subsequently, the electrostatic atomic and molecular properties such as the net charges, the molecular dipolar moment to highlight the nature of charge transfer existing within the molecule studied are derived. Moreover, the obtained electrostatic potential enables the localization of the electropositive and the electronegative parts of the investigated molecule. The present work reports in detail the obtained electrostatic properties of this biologically important molecule.

关键词： electron charge density electrostatic potential molecular dipole moment and x-ray diffraction

Theoretical prediction of structural,electronic and optical properties of quaternary alloy Zn_(1-x)Be_xS_ySe_(1-y)

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Chinese Physics B 2012年第3期21卷 321-327页

作者： Hacini K Meradji H Ghemid S El Haj Hassan F laboratoire LPR D'epartement de PhysiqueFaculté des SciencesUniversité de Annaba laboratoire de physique des Matériaux Faculté des SciencesUniversité Libanaise

Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexSySe1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg（x, y） has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexSySe1-y in conditions of being lattice matched to ZnS substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.

关键词： density functional theory full potential-linearized augmented plane wave method qua-ternary alloy lattice-matched substrate

Nonlinear Shell Models of Kirchhoff-Love Type:Existence Theorem and Comparison with Koiter's Model

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Acta Mathematicae Applicatae Sinica 2019年第1期35卷 3-27页

作者： Cristinel MARDARE Sorbonne Université CNRS Laboratoire Jacques-Louis LionsLJLL

We define two nonlinear shell models whereby the deformation of an elastic shell with small thickness minimizes ad hoc functionals over sets of admissible deformations of Kirchhoff-Love type. We establish that both models are close in a specific sense to the well-known nonlinear shell model of W.T. Koiter and that one of them has a solution, by contrast with Koiter's model for which such an existence theorem is yet to be proven.

关键词： Nonlinearly Elastic Shells Kirchhoff-Love Koiter Existence Theory Asymptotics

Direct oxidation of methane to oxygenates over heteropolyanions

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Journal of Natural Gas Chemistry 2008年第3期17卷 309-312页

作者： Ouarda Benlounes Sadia Mansouri Chérifa Rabia Smain Hocine laboratoire de Chimie Appliqueé et de Génie Chimique Université Mouloud Mammeri laboratoire de Chimie du Gaz Naturel Institut de Chimie USTHB

Partial oxidation of methane to formaldehyde and methanol was studied at atmospheric pressure in the temperature range of 700-750 °C using heteropolycompound catalysts （NH4）6HSiMo11FeO40, （NH4）4PMo11FeO39, and H4PMo11VO40, which were prepared and characterized by various analysis techniques such as infrared, visible UV, XRD and DTA. O2 or N2O was used as the oxidizing agent, and the principal products of the reaction were CH3OH, CH2O, CO, CO2, and water. The conversion and the selectivity of products depend strongly on the reaction temperature, the nature of oxidizing agent, and the composition of catalyst.

关键词： methane oxidation heteropolycompounds methanol oxygenates

The Quantum Trihedron

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Chinese Physics Letters 2016年第11期33卷 28-30页

作者： A.Bendjoudi N.Mebarki laboratoire de Physique Mathematique et Subatomique Freres Mentouri University

The convex hull on three points in two-dimensional Euclidean space of three flat edges （trihedron） is studied. The Bohr-Sommerfeld quantization of the area of space is performed. It is shown that it reproduces exact... 详细信息

关键词： of in that is

X Y Z particles at BABAR

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Chinese Physics C 2010年第6期34卷 644-649页

作者： E.Prencipe LAPP-laboratoire de Annecy de Physique de Particules

This paper intends to shortly summarize the recent results on Spectroscopy, published from the BABAR Collaboration. The BABAR experiment is a B-factory, at SLAC, where asymmetric energy beams of electron-positron are accelerated and collide at the energy in the center of mass of T（4S）. In 9 years of data taking, BABAR had collected 433 fb^-1 equivalent luminosity on-peak-data at the T（4S） energy, 30 fb^-1 data at the T（3S） energy, 15 fb^-1 data at the T（2S） energy, and a scan around T（4S） was done, collecting 25 pb^-1 every 5 MeV. Thanks to the high luminosity achieved, it is possible to perform high precision measurements, and spectroscopy studies. An update on the measurement of the state X（3872） will be given, as final result published by using the whole dataset available. Then, a new preliminary Y（4260） measurement is reported, and the study of the invariant mass J/ψπ^＋π^- in ISR events is shown, where no evidence of the state Y（4050） is highlighted. As conclusion, the results on the angular distribution analysis performed on the state Z（4430） are reported.

关键词： spectroscopy charmonium BABAR