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Friction 2024年第8期12卷 1785-1800页

作者： Javier BlANCO-RODRÍGUEZ Jacobo PORTEIRO Joséa.lÓPEZ-CAMPOS MartíCORTADA-GARCÍA Silvia FERNÁNDEZ-CASTEJÓN CINTECX Universidade de VigoLagoas-Marcosende s/nVigo 36310Spain Repsol SA MadridSpain

Durability and reliability have been studied for decades through intensive trial-error ***,there are numerous fields of application where the costs associated with this approach are not *** lubricated machines with severe dynamic loads,such as high-power-density engines,simulation tools offer clear advantages over intensive *** and multiple scenarios can be cost-effectively simulated to assess different lubricants and engine *** work presented here deta.ls the study of wear based on a validated elastohydrodynamic(EHD)simulation model of the connecting rod journal *** model accounts for elastic deformation through a connecting rod finite element model(FEM).In addition,multiple lubricant rheological and tribological dependences,determined by specific experimental tests,are applied in the model through their interaction with the simulation ***,a novel wear algorithm is proposed to predict wear depth over time evolution along a proposed wear cycle based on the typical working ranges of high-performance engines.A final assessment is presented to compare 4 different ultralow-viscosity lubricants in their protective performance under severe *** results show the evolution of the wear load and wear depth over the wear *** evaluation is key to describing a.lubricant selection procedure for high-power-density engines.

关键词： wear modelling finite element modelling mixed lubrication elastohydrodynamic(EHD) internal combustion engines bearings

放射性核素和纹理计年对比研究瑞士格莱芬湖近代沉积速率

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地球化学 1986年第3期15卷 259-270页

作者：万国江 P.H.Santschi M.Sturm K.Farrenkothen a.lüeck W.Werth Chr.Schuler 中国科学院地球化学研究所瑞士联邦水资源和水污染控制研究所

本文利用纹理年代、核试验散落核素时标及^(210)Pb计年方法,对比研究了瑞士格莱芬湖中部的现在沉积速率。发现前两种方法给出了一致的结果,而^(210)Pb方法所获结果明显地偏低。在排除各种可能原因后,笔者认为产生上述现象的机理是:^(210... 详细信息

本文利用纹理年代、核试验散落核素时标及^(210)Pb计年方法,对比研究了瑞士格莱芬湖中部的现在沉积速率。发现前两种方法给出了一致的结果,而^(210)Pb方法所获结果明显地偏低。在排除各种可能原因后,笔者认为产生上述现象的机理是:^(210)Pb通过孔隙水作用而从沉积物中扩散丢失。表层沉积物孔隙水中^(210)Pb及^(210)Po的测量,证实了上述假设。

关键词：放射性核素纹理计年沉积年代学瑞士格莱芬湖沉积速率

On the functions of astrocyte-mediated neuronal slow inward currents

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Neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs Pál Department of Physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic N-met hyl-D-aspartate receptors with the contribution of *** events are significantly slower than the excitatory postsynaptic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic *** addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory *** note,there might be important regionspecific differences in the roles and actions triggering slow inward *** greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological *** inward currents are identified in the pathophysiological background of autism,as slow inward currents drive ea.ly hypersynchrony of the neural *** inward currents are significant contributors to paroxysmal depolarizational shifts/interictal *** events are related to epilepsy,but also found in Alzheimer's disease,Parkinson's disease,and stroke,leading to the decline of cognitive *** with features overlapping with slow inward currents(excitatory,N-methyl-Dasp

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization NMDA receptor paroxysmal depolarizational shift slow inward current

On calculating glacial isostatic adjustment

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Geodesy and Geodynamics 2024年第5期15卷 441-452页

作者： l.M.Cathles Cornell University IthacaNY 14853USA

Modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity ***,we compare two methods for calculating the viscoelastic response to surface *** one,the elastic equation of motion is converted to a viscoelastic equation using the Correspondence *** the other,elastic deformation is added to the viscous flow as isostatic adjustment *** two modeling methods predict adjustment histories that are different enough to potentia.ly impact the interpretation of the observed glacial isostatic adjustment(GIA).The differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic *** methods agree if they use the same equations and boundary *** origin of the differences is determined by varying the boundary conditions and pre-stress application.

关键词： Glacial isostatic adjustment Viscoelastic normal modes Hydrostatic pre-stress Elastic buoyancy Correspondence principle

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l Silva.l.A.O.Nunes S.M.lima.l.H.C.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Ca.los University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Non-adhesive and adhesive contacts of an elastic quarter-or eighth-space with freely sliding sides

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Friction 2024年第9期12卷 2052-2063页

作者： Qiang lI Valentin l.POPOV Technische Universität Berlin Berlin 10623Germany

The contact of an elastic quarter-or eighth-space is studied under the condition that the movement of the side surface of the quarter-space is constrained:It can slide freely along the plane of the side surface but its normal movement is blocked(for example,by a rigid wa.l).The solution of this contact problem can be easily achieved by additiona.ly applying a mirrored load to an elastic ***-adhesive contact and the Johnson–Kenda.l–Roberts(JKR)-type adhesive contact between a rigid sphere and an elastic quarter-space under such a boundary condition is numerica.ly simulated using the fast Fourier transform(FFT)-assisted boundary element method(BEM).Contacts of an elastic eighth-space are investigated using the same *** on the position of the sphere relative to the side edge,different contact behavior is *** the case of adhesive contact,the force of adhesion first increases with increasing the distance from the edge of the quarter-space,achieves a maximum,and decreases further to the JKR-value in large distance from the *** enhancement of the force of adhesion compared to the half-space-contact is associated with the pinning of the contact area at the *** provide the maps of the force of adhesion and their analytical approximations,as well as pressure distributions in the contact plane and inside the quarter-/eighth-space.

关键词： quarter-space eighth-space adhesion edge effect boundary element method(BEM)

Quantum vortices get stretched

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Frontiers of physics 2024年第3期19卷 225-227页

作者： Emanuel a.l.Henn São Ca.los Institute of Physics University of São Paulo-PO Box 36913560-970São CarlosBrazil

Since its discovery, superfluidity [1,2] remains one of the most remarka.le phenomena in quantum physics. The onset of the quantum regime in liquid helium is visua.ly striking, when the fluid flows without dissipation or detaches from a rotating bucket, remaining still upon soft rotations. The same phenomenon is present in the context of ultracold bosonic quantum gases where, most of the time, superfluidity walks hand-in-hand with the transition to Bose−Einstein condensation [3].

关键词： quantum rotating rotation

Time-inconsistent stochastic linear-quadratic control problem with indefinite control weight costs

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Science China Mathematics 2024年第1期67卷 211-236页

作者： Qi lü Bowen Ma School of Mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent linear-quadratic optimal control problem for stochastic differential equations is *** introduce conditions where the control cost weighting matrix is possibly *** such conditions,we obtain a family of closed-loop equilibrium strategies via multi-person differential *** result extends Yong’s work(2017) in the case of stochastic differential equations,where a unique closed-loop equilibrium strategy can be derived under standard conditions(namely,the control cost weighting matrix is uniformly positive definite,and the other weighting coefficients are positive semidefinite).

关键词： linear-quadratic optimal control problem time-inconsistent cost functional generalized Riccati equation indefinite control weight cost closed-loop equilibrium strategy

Rogue wave solutions and rogue-breather solutions to the focusing nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 33-41页

作者： Si-Jia Chen Xing lü College of Science Tianjin University of TechnologyTianjin 300384People's Republic of China Department of Mathematics Beijing Jiaotong UniversityBeijing 100044People's Republic of China Beijing laboratory of National Economic Security Ea.ly-warning Engineering Beijing Jiaotong UniversityBeijing 100044People's Republic of China

Based on the long wave limit method,the general form of the second-order and third-order rogue wave solutions to the focusing nonlinear Schr?dinger equation are given by introducing some arbitrary *** interaction solutions between the first-order rogue wave and one-breather wave are constructed by taking a.long wave limit on the two-breather *** applying the same method to the three-breather solutions,two types of interaction solutions are obtained,namely the first-order rogue wave and two breather waves,the second-order rogue wave and one-breather wave,*** influence of the parameters related to the phase on the interaction phenomena is graphica.ly *** occur among the rogue waves and breather *** the collisions,the shape of them remains *** abundant interaction phenomena in this paper will contribute to a better understanding of the propagation and control of nonlinear waves.

关键词： nonlinear Schrodinger equation rogue wave solutions interaction solutions

A Pooling Method Developed for Use in Convolutional Neural Networks

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 751-770页

作者： Ìsma.l Akgül Departmant of Computer Engineering Faculty of Engineering and ArchitectureErzincan Binali Yıldırım UniversityErzincan24002Turkiye

In convolutional neural networks,pooling methods are used to reduce both the size of the data and the number of parameters after the convolution of the *** methods reduce the computational amount of convolutional neural networks,making the neural network more *** pooling,average pooling,and minimum pooling methods are genera.ly used in convolutional neural ***,these pooling methods are not suita.le for a.l datasets used in neural network *** this study,a new pooling approach to the literature is proposed to increase the efficiency and success rates of convolutional neural *** method,which we ca.l MAM(Maximum Average Minimum)pooling,is more interactive than other traditional maximum pooling,average pooling,and minimum pooling methods and reduces data.loss by calculating the more appropriate pixel *** proposed MAM pooling method increases the performance of the neural network by calculating the optimal value during the training of convolutional neural *** determine the success accuracy of the proposed MAM pooling method and compare it with other traditional pooling methods,training was carried out on the leNet-5 model using CIFAR-10,CIFAR-100,and MNIST *** to the results obtained,the proposed MAM pooling method performed better than the maximum pooling,average pooling,and minimum pooling methods in a.l pool sizes on three different datasets.

关键词： Pooling convolutional neural networks deep learning