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中国口腔颌面外科杂志 2009年第5期7卷 400-400页

作者： Ayad T Guertin L soulières d

该综述旨在讨论目前对磨牙后区黏膜癌在处理方面所存在的争论,认为发生于磨牙后区的恶性肿瘤应单独对待。术前应强调临床及影像学评价,以明

关键词：黏膜下颌骨颌患者

Experimental measurements of gamma-photon production and estimation of electron/positron production on the PETAL laser facility

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Matter and Radiation at Extremes 2024年第5期9卷 32-47页

作者： F.Brun L.Ribotte G.Boutoux X.davoine P.E.Masson-Laborde Y.Sentoku N.Iwata N.Blanchot d.Batani I.Lantuéjoul L.Lecherbourg B.Rosse C.Rousseaux B.Vauzour d.Raffestin E.d’Humières X.Ribeyre Centre Lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance CEA DAMCESTAF-33116 Le BarpFrance CEA DAMDIFF-91297 ArpajonFrance CEA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity PETawatt Aquitaine Laser(PETAL)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SESAME(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and L-shells were clearly detected by a photon spectrometer called SPECTIX(Spectromètre PetalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chambre-rayonnement X),a bremsstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was *** simulations model the preplasma generated at the front of the target by the PETAL laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enabled reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process positron hypothesis

Optimizing laser coupling,matter heating,and particle acceleration from solids using multiplexed ultraintense lasers

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Matter and Radiation at Extremes 2024年第4期9卷 16-28页

作者： Weipeng Yao Motoaki Nakatsutsumi Sébastien Buffechoux Patrizio Antici Marco Borghesi Andrea Ciardi Sophia N.Chen Emmanuel d’Humières Laurent Gremillet Robert Heathcote Vojtech Horny Paul McKenna Mark N.Quinn Lorenzo Romagnani Ryan Royle Gianluca Sarri Yasuhiko Sentoku Hans-Peter Schlenvoigt Toma Toncian Olivier Tresca Laura Vassura Oswald Willi Julien Fuchs LULI-CNRS CEASorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Université Observatoire de ParisUniversité PSLCNRSLERMAF-75005 ParisFrance INRS-EMT 1650 BoulLionel-BouletVarennesQuebec J3X 1S2Canada Center for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUnited Kingdom “Horia Hulubei”National Institute for Physics and Nuclear Engineering 30 Reactorului StreetRO-077125 Bucharest-MagureleRomania University of Bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance CEA DAMDIFF-91297 ArpajonFrance Université Paris-Saclay CEALMCE91680 Bruyères-le-ChatelFrance Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUnited Kingdom SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom department of Physics University of NevadaRenoNevada 89557USA Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan Institut fur Laser und Plasmaphysik Heinrich Heine Universitat DusseldorfDusseldorfGermany

Realizing the full potential of ultrahigh-intensity lasers for particle and radiation generation will require multi-beam arrangements due to technology ***,we investigate how to optimize their coupling with solid ***,we show that overlapping two intense lasers in a mirror-like configuration onto a solid with a large preplasma can greatly improve the generation of hot electrons at the target front and ion acceleration at the target *** underlying mechanisms are analyzed through multidimensional particle-in-cell simulations,revealing that the self-induced magnetic fields driven by the two laser beams at the target front are susceptible to reconnection,which is one possible mechanism to boost electron *** addition,the resistive magnetic field generated during the transport of the hot electrons in the target bulk tends to improve their *** simulations also indicate that such effects can be further enhanced by overlapping more than two laser beams.

关键词： laser acceleration particle

Advancing Wound Filling Extraction on 3d Faces:An Auto-Segmentation and Wound Face Regeneration Approach

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2197-2214页

作者： duong Q.Nguyen Thinh d.Le Phuong d.Nguyen Nga T.K.Le H.Nguyen-Xuan department of Mathematics and Statistics Quy Nhon UniversityQuy Nhon City55100Viet Nam Applied research Institute for Science and Technology Quy Nhon UniversityQuy Nhon City55100Viet Nam CIRTECH Institute HUTECH UniversityHo Chi Minh City72308Viet Nam

Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical *** this paper,we propose an efficient approach for automating 3d facial wound segmentation using a two-stream graph convolutional *** method leverages the Cir3d-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss *** achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the *** selectedmodel demonstrates exceptional segmentation performance for complex 3d facial ***,based on the segmentation model,we propose an improved approach for extracting 3d facial wound fillers and compare it to the results of the previous *** method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous *** this result,we use 3d printing technology to illustrate the shape of the wound *** outcomes of this study have significant implications for physicians involved in preoperative planning and intervention *** automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient ***,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3d bioprinting for printing skin tissue *** source code is available at https://***/SIMOGroup/WoundFilling3d.

关键词： 3d printing technology face reconstruction 3d segmentation 3d printed model

Numerical analysis of high‑speed railway slab tracks using calibrated and validated 3d time‑domain modelling

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Railway Engineering Science 2024年第1期32卷 36-58页

作者： A.F.Esen O.Laghrouche P.K.Woodward d.Medina‑Pineda Q.Corbisez J.Y.Shih d.P.Connolly Institute for High‑Speed Rail and System Integration University of LeedsLeeds LS29JTUK Institute for Infrastructure and Environment Heriot-Watt UniversityEdinburgh EH144ASUK Alstom Transport Saint‑OuenFrance Birmingham Centre for Railway research and Education University of BirminghamBirmingham B152TTUK

Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance *** this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in *** is then compared to the performance of a ballasted ***,slab and ballasted track models are developed to replicate the full-scale testing of track *** the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track *** slab and ballasted track models are then extended to create linear dynamic models,considering the track geodynamics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the *** travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical *** train loading methods are discussed,and the most practical approach is retained and ***,correlations are made between the geotechnical parameters of modern high-speed rail and conventional *** is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds.

关键词： High-speed railways Slab track New ballastless track Ballasted track Critical speeds Finite element modelling Calibration of numerical models

Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： Andreas döpp Ludwig-Maximilian-Universität München Am Coulombwall 185748GarchingGermany Max Planck Institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 563-580页

作者： N.HUMNEKAR d.SRINIVASACHARYA department of Mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is *** darcyBrinkman model is used to characterize the fluid flow dynamics in porous *** analytical solutions are obtained for the unidirectional and completely developed *** on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is *** eigenvalue problem is then solved by the spectral ***,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing *** results show that increasing the darcy number,the Lewis number,the dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the ***,the flow is the most unstable when the channel is vertically oriented.

关键词： nanofluid inclined channel variable viscosity linear stability double dif-fusion porous medium

Improved Leap-frog Method for Time-domain Fault Location

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 670-674页

作者： Izudin džafić Rabih A.Jabr Faculty of Electrical Engineering University of SarajevoSarajevo 71000Bosnia and Herzegovina department of Electrical and Computer Engineering American University of BeirutBeirut 11072020Lebanon IEEE

The partial differential equation(PdE)solution of the telegrapher is a promising fault location method among time-domain and model-based *** research works have shown that the leap-frog process is superior to other explicit methods for the PdE ***,its implementation is challenged by determining the initial conditions in time and the boundary conditions in *** letter proposes two implicit solution methods for determining the initial conditions and an analytical way to obtain the boundary conditions founded on the signal *** results show that the proposal gives fault location accuracy superior to the existing leap-frog scheme,particularly in the presence of harmonics.

关键词： Fault location leap-frog partial differential equation time-domain analysis transmission line

The Effect of External Magnetic Field on Electron Scale Kelvin–Helmholtz Instability

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research in Astronomy and Astrophysics 2024年第9期24卷 236-247页

作者： d.Tsiklauri Joule Physics Laboratory School of ScienceEngineering and EnvironmentUniversity of SalfordManchesterM54WTUK

We use particle-in-cell,fully electromagnetic,plasma kinetic simulation to study the effect of external magnetic field on electron scale Kelvin–Helmholtz instability(ESKHI).The results are applicable to collisionless plasmas when,e.g.,solar wind interacts with planetary magnetospheres or a magnetic field is generated in AGN *** find that as in the case of magnetohydrodynamic(MHd)KHI,in the kinetic regime,the presence of an external magnetic field reduces the growth rate of the *** the MHd case,there is a known threshold magnetic field for KHI stabilization,while for ESKHI this is to be analytically *** a kinetic analytical expression,we use several numerical simulation runs to establish an empirical dependence of ESKHI growth rate,Γ(B_(0))ω_(pe),on the strength of the applied external magnetic *** find the best fit is hyperbolic,Γ(B_(0))ω_(pe)=Γ_(0)ω_(pe)/(A+BB_(0)),where Γ_(0) is the ESKHI growth rate without an external magnetic field and B_(0)=B_(0)/B_(MHd)is the ratio of external and two-fluid MHd stability threshold magnetic field,derived *** analytical theory to back up this growth rate dependence on the external magnetic field is *** results suggest that in astrophysical settings where a strong magnetic field pre-exists,the generation of an additional magnetic field by the ESKHI is suppressed,which implies that nature provides a“safety valve”—natural protection not to“over-generate”magnetic field by the ESKHI ***,we find that our two-fluid MHd threshold magnetic field is the same(up to a factor √γ_(0))as the dC saturation magnetic field,previously predicted by fully kinetic theory.

关键词： instabilities magnetic fields plasmas Sun:heliosphere ISM:magnetic fields

decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and dFT calculations

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Journal of Environmental Sciences 2024年第1期135卷 433-448页

作者： Xiang Meng Pierre désesquelles Lejin Xu department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science&TechnologyWuhan 430074China CNRS Laboratoire de Physique des Gaz et des PlasmasUniversitéParis-SaclayOrsay 91405France State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The treatment and disposal of radioactive waste are presently facing great *** ion exchange resins have become a focus of attention due to their high production and serious environmental *** this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(dFT)*** prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the *** meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain *** C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily *** is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring *** decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons.

关键词： Cationic exchange resin Statistical molecular fragmentation model density functional theory Hydroxyl radical decomposition mechanism