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On Blow-up of Regular Solutions to the Isentropic Euler and Euler-Boltzmann Equations with Vacuum

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Chinese Annals of Mathematics,Series B 2021年第4期42卷 495-510页

作者： yue CAO Yachun LI School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences MOE-LSCand SHL-MACShanghai Jiao Tong UniversityShanghai 200240China

In this paper,the authors study the Cauchy problem of n-dimensional isentropic Euler equations and Euler-Boltzmann equations with vacuum in the whole *** show that if the initial velocity satisfies some condition on the integral J in the"isolated mass group"(see(1.13)),then there will be finite time blow-up of regular solutions to the Euler system with J≤0(n≥1)and to the Euler-Boltzmann system with J<0(n≥1)and J=0(n≥2),no matter how small and smooth the initial data *** is worth mentioning that these blow-up results imply the following:The radiation is not strong enough to prevent the formation of singularities caused by the appearance of vacuum,with the only possible exception in the case J=0 and n=1 since the radiation behaves differently on this occasion.

关键词： Euler and Euler-Boltzmann equations Finite time blow-up Multi-dimensional Regular solutions Vacuum

Microstructure and Microhardness of Tempered Ni-Al Alloyed Layer

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Journal of Materials Science & Technology 2012年第10期28卷 937-940页

作者： yue Yang Hua Wu College of Materials Science and Engineering Changchun University of TechnologyChangchun130012China

A Nd：YAG pulsed laser was used to alloy the Ni-P electroless deposited coating with aluminum substrate under the condition of scanning speed of 3.0 mm/s and power density of 5.36×10^9 W/m^2. Subsequently, the samples were heat treated at 300, 400 and 500 ℃ for 2.5 h, respectively. The phase composition and microstructure of the tempered layers treated at different temperature were identified by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The results showed that the phase constituents of the alloyed zones were intermetallic compounds of NiAI, AI3Ni, Ni3P and AINi3. As a result, the microhardness of the alloyed layer after heat treatment was improved obviously compared to untreated samoles, and the laver obtained at teml0erature 400 ℃ reached HVn.1 430.

关键词： Laser alloying Nickel-aluminum intermetallics Heat treatment Microhardness

Machine Learning and Micromagnetic Studies of Magnetization Switching

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Chinese Physics Letters 2019年第9期36卷 64-67页

作者： Jing-yue Miao Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084 Argonne National Laboratory ChicagoUSA

Magnetization switching is one of the most fundamental topics in the field of *** learning(ML)models of random forest(RF),support vector machine(SVM),deep neural network(DNN)methods are built and trained to classify the magnetization reversal and non-reversal cases of single-domain particle,and the classification performances are evaluated by comparison with micromagnetic *** results show that the ML models have achieved great accuracy and the DNN model reaches the best area under curve(AUC)of 0.997,even with a small training dataset,and RF and SVM models have lower AUCs of 0.964 and 0.836,*** work validates the potential of ML applications in studies of magnetization switching and provides the benchmark for further ML studies in magnetization switching.

关键词： Deep neural networks

Large-scale amplitude liquid sloshing in container under pitching excitation

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Chinese Science Bulletin 2008年第24期53卷 3816-3823页

作者： yue BaoZeng Department of Mechanics School of Science Beijing Institute of Technology Beijing 100081 China

Large-scale amplitude liquid sloshing in container under pitching excitation is numerically studied in this ***,the kinematics of the ALE description is introduced and the fluid dynamics equations are revised in the ALE ***,the boundary condition about free-surface tension is represented in the form of weak integration that can be computed by the differential geometry method derived in the present paper and the normal vector on free surface is calculated using accurate formulas presented in this *** the numerical discretized equations of fractional step finite element method are developed by Galerkin weighted residual ***,the numerical simulation of large-scale amplitude sloshing of the liquid both in rectangular container and cylindrical container is carried *** computed time evolution of the wave height,and free surface profiles at different time are *** among the present numerical results with other published numerical results and experimental data confirm the effectiveness and validity of the method developed in this paper.

关键词：纵摇激发数字模拟液体晃动自由面张力

Preface of the Special Issue: Queueing Systems and Engineering Applications

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Journal of Systems Science and Systems Engineering 2019年第2期28卷 129-131页

作者： Wuyi yue Yutaka Takahashi Department of Intelligence and Informatics Konan University Kobe 658-8501 Japan Graduate School of Informatics Kyoto University Kyoto 606-8501 Japan

This volume of the Journal of Systems Science and Systems Engineering is devoted to the extended versions of papers selected and presented at the 12th International Conference on Queueing Theory and Network Applicatio... 详细信息

关键词： Systems 12th Applications

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Plant Diversity 2021年第2期43卷 111-116页

作者： Juan yue Rong Li CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of Sciences Beijing100049China

The species composition of plant communities is determined by a number of factors,including current environmental conditions as well as biogeographical and evolutionary *** evidence that plant diversity decreases and species relatedness increases along latitudinal and environmental gradients(e.g.,low temperatures),it remains unclear whether these same patterns occur along elevational gradients,especially in the subtropical mountainous areas harboring rich *** this study,we explored the pattern of phylogenetic relatedness of woody angiosperm assemblages and examined the effects of temperature variables on the phylogenetic relatedness among angiosperm woody plants using generalized linear model in subtropical forest communities along a broad elevational gradient in the Dulong Valley of Yunnan Province,*** results showed that woody angiosperm species in local forest plots tend to be more phylogenetically related at higher elevations and in areas with lower ***,winter average temperature,rather than mean annual temperature,is a major predictor of the pattern of increasing phylogenetic relatedness with increasing *** finding is consistent with the prediction of‘Tropical Niche Conservatism’hypothesis,which highlights the role of niche constraints in driving phylogenetic community assembly along an elevational gradient.

关键词： Dulong Valley Ecological tolerance Habitat filtering Niche conservatis

Rapidly Solidified Microstructure in Laser Alloyed Ni-Al Layer by TEM, STEM z-contrast and HRTEM Techniques

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Journal of Materials Science & Technology 2014年第12期30卷 1301-1303页

作者： yue Yang Jiandong Hu College of Materials Science and Engineering Changchun University of Technology The Key Lab of Automobile Materials Ministry of Education College of Materials Science and Engineering Jilin University

In the present study, laser alloying of electroless Nie P coating on aluminum substrate was conducted using Nd：YAG pulsed laser under the condition of 5.36 109W/m2 in power density and 3.0 mm/s in scanning speed. The rapidly solidified microstructure in the alloyed layer was studied. The results showed that the alloying element distributed in the alloyed layer is inhomogeneous. The dendrite containing relatively high Ni was identified as Al3Ni phase and the areas between the dendrites are rich in Al content. Featureless with cell structure in Al-rich areas was firstly displayed by z-contrast image. Amorphous structure was revealed to exist in Al-rich areas.

关键词： Laser alloying Microstructure Featureless structure

Evaluation of Routed-Runoff from Land Surface Models and Reanalyses Using Observed Streamflow in Chinese River Basins

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Journal of Meteorological Research 2020年第1期34卷 73-87页

作者： yue MIAO Aihui WANG Nansen–Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 University of Chinese Academy of Sciences Beijing 100049

Previous studies have demonstrated that offline land surface models(LSMs)and global hydrological models(GHMs)can reasonably reproduce streamflow in large river *** reanalyses supply fine spatiotemporal runoff estimates,but they are not fully intercompared and evaluated in *** study assesses the routed-runoff from five offline LSM/GHM runs(VIC-CN05.1,CLM-CFSR,CLM-ERAI,CLM-MERRA,and CLM-NCEP)and three reanalysis datasets(ERAI/Land,JRA55,and MERRA-2)against the gauged streamflow(26 stations)in major Chinese river basins during 1980–*** Catchment-based Macro-scale Floodplain model(CaMa-Flood)is employed to route those runoff datasets to the hydrological *** statistical quantities,including the correlation coefficient(R),standard deviation(STD),Nash–Sutcliffe efficiency coefficient(NSE),and relative error(RE),along with a ranking method,are used to quantify the quality of those *** results show that the spatial patterns of both modeled and observed streamflow in summer are similar,but their magnitudes are *** for MERRA-2,the other products can reproduce well the interannual variability of streamflow in both the Yangtze and Yellow River *** products generally underestimate the magnitude and variance of monthly streamflow,while VIC-CN05.1 and JRA55 are closer to observations compared to other *** correlation coefficients for all products are overall larger than 0.61,with the highest value(0.85)from *** addition to CLM-MERRA,MERRA-2,and CLM-NCEP with relatively small precipitation,other products can simulate peak flow well with positive NSEs up to 0.41(ERAI/Land).Considerable uncertainties exist among the eight products at the Yellow River outlet,which might be because the LSMs ignore frequent human *** on the above statistics,performances of the eight runoff products are ranked in descending order as follows:VIC-CN05.1,ERAI/Land,JRA55,CLM-CFSR,CLM-ERAI,MERRA-2,CLM-MERRA,and CLM-NCE

关键词： runoff land surface model(LSM) reanalysis data Catchment-based Macro-scale Floodplain model(CaMa-Flood) observed streamflow

Population evolution at the prefecture-level city scale in China:Change patterns and spatial correlations

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Journal of Geographical Sciences 2022年第7期32卷 1281-1296页

作者： XIAN yue CHEN Mingxing Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resource and Environment University of Chinese Academy of SciencesBeijing 100049China

China has entered a new stage of high-quality ***,it is critical to grasp the latest population distribution and *** mean-variance grading,Moran’s index,and the Theil index,this study compared the differences in population changes between 2010–2020 and 2000–2010 at the prefecture-level city scale based on census data to analyze the new trends in population *** found that:(1)New growth poles of the population are inland provincial capitals,forming rapid-growing zones together with coastal urban *** growth in over 60%of the cities in the northern coastal urban agglomeration has slowed.(2)The scope of population loss in inland areas is constantly *** the northeastern part of China,92.7%of the cities have lost population,making this a typical population loss area.(3)Population shrinkage in the northeastern region and growth in the Pearl River Delta urban agglomeration show diffusion characteristics,while population patterns around the provincial capital are in a polarized stage.(4)The Theil index of population distribution increased,with 83.91%of differences coming from between groups,indicating that the gap between cities of different sizes has further *** study provides scientific support for the coordinated promotion of nearby and remote urbanization.

关键词： population distribution agglomeration and decentralization pattern change nearby urbanization prefecture-level city