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Journal of Materials Science & Technology 2002年第3期18卷 197-205页

作者： JiuzhouZHAO l.ratke 等 TheInstituteofMetalResearch ChineseAcademyofSciencesShenyang110016China TheInstituteforSpaceSimulation DLRD-511470CologneGermany

The microstructure development during a cooling period of alloys being immiscible in the liquid state such as Al-Pb or Al-Bi has gained a renewed scientific and technical interest during the last decades. Experiments have been performed to investigate the phase transformation kinetics in the liquid miscibility gap, and numerical models have been developed to simulate and analyze the solidification process. The recently developed computational modeling techniques can, to some extent, be applied to describe the decomposition, the spatial phase separation and the microstructure evolution during a cooling period of an immiscible alloy through the miscibility gap. This article overviews these researches in this field.

关键词： Immiscible alloy Solidification Microstructure Modeling

Modeling of the Microstructure Evolution in Continuously Cast Al-pb Alloys

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Journal of Materials Science & Technology 2002年第4期18卷 306-310页

作者： JiuzhouZHAO l.ratke InstituteofMetalResearch ChineseAcademyofSciencesShenyang110016China InstituteforSpaceSimulation DLRD-51140CologenGermany

A numerical model is presented describing the microstructure evolution of an immiscible alloy under the continuous casting conditions. Calculations are carried out to investigate the microstructure evolution in a vertical strip cast sample of Al+5wt pct Pb alloy. The numerical results show that there exists a peak value for the supersaturation in front of the solid祃iquid interface, and the minority phase droplets are nucleated in a region around this peak. Under strip casting conditions the Marangoni migration dominates the motion of droplets. This leads to an accumulation of the minority phase droplets in front of the solid祃iquid interface.

关键词： Immiscible alloy Continuous casting Microstructure Numerical simulation

Effect of Brownian Coagulation on the liquid-liquid Decomposition in Gas-atomized Alloy Drops

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Journal of Materials Science & Technology 2006年第3期22卷 321-323页

作者： Jiuzhou ZHAO lingling GAO Jie HE l.ratke Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China The Institute for Space Simulation DLR 51140 Cologne Germany

Modeling and simulation have been carried out for Al-Pb alloys to investigate the Brownian coagulation effect on the microstructure development in a gas-atomized drop during the liquid-liquid decomposition. The results indicate that Brownian coagulation has a weak effect on the nucleation and a relatively strong effect on coarsening the minority phase droplets. The influence of Brownian coagulation on the liquid-liquid decomposition decreases with the increase in the diameter （or the decrease in the cooling rate） of the atomized drop.

关键词： Immiscible alloy Rapid solidification Atomization Brownian coagulation Modeling

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偏晶合金液-液相变过程模拟

金属学报 2004年第1期40卷 27-30页

作者：赵九洲胡壮麒 l.ratke 中国科学院金属研究所沈阳110016 Institute for Space Simulation Deutsches zentrum für Luft-und RaumfahrtGermany

建立了能描述在弥散相液滴形核、扩散长大、碰撞凝并及两液相空间分离等因素共同作用下,偏晶合金液-液相变过程中组织演变过程的数学模型,将计算的温度场和浓度场与控制凝固组织演变的动力学方程相耦合,模拟研究了单向冷却条件下Al-Pb... 详细信息

建立了能描述在弥散相液滴形核、扩散长大、碰撞凝并及两液相空间分离等因素共同作用下,偏晶合金液-液相变过程中组织演变过程的数学模型,将计算的温度场和浓度场与控制凝固组织演变的动力学方程相耦合,模拟研究了单向冷却条件下Al-Pb合金液-液相变过程中的组织演变过程。结果表明,随着冷却的进行,液-液相变区不断由试样底部向试样顶部推进,直至贯穿整个试样,由于在凝固过程中弥散相液滴进行Marangoni迁移和Stokes运动,试样中的某些部位会出现液滴贫化、过饱和度增加和多次形核现象。

关键词：偏晶合金,液-液相变,微观组织演变,模拟

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高度多孔纳米结构纤维素纤维的溶液纺丝工艺

国际纺织导报 2009年第8期37卷 38-40,42页

作者： C．Hacker T．Gries C．Popescu l.ratke 骆为林（译）行兰（校）德国亚琛纺织技术研究所德国羊毛研究所德国宇航研究院不详

由纤维素生产纤维的常规生产方法,迄今已生产了具有致密微结构和极大长径比的材料。在此介绍的表面多孔的纤维是一种新型纤维状材料,为科学家和工程师提供了许多挑战和机会。由于纳米结构纤维的特性,它在工业产品,例如从过滤到类似药物... 详细信息

由纤维素生产纤维的常规生产方法,迄今已生产了具有致密微结构和极大长径比的材料。在此介绍的表面多孔的纤维是一种新型纤维状材料,为科学家和工程师提供了许多挑战和机会。由于纳米结构纤维的特性,它在工业产品,例如从过滤到类似药物释放载体的特殊产品的许多用途中具有很大潜力。通过采用溶胶凝胶方法,首次制成了表面多孔的纳米结构纤维素纤维。

关键词：纳米结构纤维素纤维溶液纺丝溶胶凝胶

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： Ìsmail 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 generally used in convolutional neural ***,these pooling methods are not suitable for all 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 call 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 all pool sizes on three different datasets.

关键词： Pooling convolutional neural networks deep learning

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 early 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

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 Carlos 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

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 Carlos Institute of Physics University of São Paulo-PO Box 36913560-970São CarlosBrazil

Since its discovery, superfluidity [1,2] remains one of the most remarkable phenomena in quantum physics. The onset of the quantum regime in liquid helium is visually 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