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Urban Redevelopment, Gentrification and Gentrifiers in Post-reform Inland China: A Case Study of Chengdu, China

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Chinese Geographical Science 2017年第1期27卷 151-164页

作者： huang xing YANG Yongchun School of Architecture State Key Laboratory of Subtropical Building Science South China University of Technology Department of Geography Kyushu University Key Laboratory of Western China's Environmental Systems School of Resource and Environmental Science Lanzhou University College of Urban and Environmental Science Northwest University

Since its process evolved in recent years, the definition of gentrification has expanded to cover different forms of social upgrading, new spaces and new actors around the world. Studies on gentrification in Chinese cities began to take off in the 2000 s. However, they all mainly focused on the newly emerging global cities and there has been a lack of investigation on provincial cities. Furthermore, discussions on gentrifiers′ profiles and their motivations for housing choice are absent from literature on Chinese gentrification. Therefore, this paper aims to assess the relevance of the broad definition of gentrification in provincial Chinese cities through empirical research on urban redevelopment projects in Chengdu, and to examine the characteristics of gentrifiers(as new incoming residents) in it. The results show the rationality of gentrification processes as urban redevelopment in Chengdu, and reveal original outcomes on the corresponding gentrifiers′ profiles and the motivations behind their housing choice, which are different from the general features of gentrifiers in standard Western gentrification research.

关键词： gentrification new-build gentrification urban redevelopment projects gentrifiers motivations for housing choice Chengdu China

Improvements in Long-Lead Prediction of Early-Summer Subtropical Frontal Rainfall Based on Arctic Sea Ice

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Journal of Ocean University of China 2019年第3期18卷 542-552页

作者： xing Wen huang Fei Key Laboratory of Physical Oceanography Ocean University of China Qingdao 266100 China Laboratory for Ocean and Climate Dynamics Pilot National Laboratory for Marine Science and Technology (Qingdao) Qingdao 266100 China Ningbo Collaborative Innovation Center of Nonlinear Harzard System of Ocean and Atmosphere Ningbo University Ningbo 315211 China

Seasonal prediction of East Asia(EA) summer rainfall, especially with a longer-lead time, is in great demand, but still very challenging. The present study aims to make long-lead prediction of EA subtropical frontal rainfall(SFR) during early summer(May-June mean, MJ) by considering Arctic sea ice(ASI) variability as a new potential predictor. A MJ SFR index(SFRI), the leading principle component of the empirical orthogonal function(EOF) analysis applied to the MJ precipitation anomaly over EA, is defined as the predictand. Analysis of 38-year observations(1979-2016) revealed three physically consequential predictors. A stronger SFRI is preceded by dipolar ASI anomaly in the previous autumn, a sea level pressure(SLP) dipole in the Eurasian continent, and a sea surface temperature anomaly tripole pattern in the tropical Pacific in the previous winter. These precursors foreshadow an enhanced Okhotsk High, lower local SLP over EA, and a strengthened western Pacific subtropical high. These factors are controlling circulation features for a positive SFRI. A physical-empirical model was established to predict SFRI by combining the three predictors. Hindcasting was performed for the 1979-2016 period, which showed a hindcast prediction skill that was, unexpectedly, substantially higher than that of a four-dynamical models’ ensemble prediction for the 1979-2010 period(0.72 versus 0.47). Note that ASI variation is a new predictor compared with signals originating from the tropics to mid-latitudes. The long-lead hindcast skill was notably lower without the ASI signals included, implying the high practical value of ASI variation in terms of long-lead seasonal prediction of MJ EA rainfall.

关键词： East Asia subtropical frontal rainfall long-lead seasonal prediction Arctic sea ice Physical-empirical model

Nucleation barrier of fcc(γ)→hcp(ε) martensitic transformation in Fe-based alloys

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Science China(Technological Sciences) 2004年第1期47卷 121-128页

作者： huang xing CHEN Shipu School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China

Based on the dislocation theory and Olson's stacking fault model, a model describing the nucleation of an hcp(ε) martensite embryo at low-angle grain boundary is proposed with the influence of external stress field taken into account. The dependences of temperature (T), shear stress (τ) and dislocation density at grain boundary on the martensite nucleation in FeMnSi based alloy, as an example, are numerically simulated. It has been shown that there exist the subcritical and critical embryos during the course of ε-phase nucleation. The free energy difference between them is just the energy barrier of embryo growth. Depending on T and τ. the characteristic embryo sizes may vary in wide ranges and decreases with increasing σ and decreasing T. The energy condition of martensitic transformation at M s and critical shear stress (τc) is discussed from the viewpoint of kinetics and thus the TEM observed result that stacking fault energy is not zero at M s temperature is reasonably explained. Besides, it is predicted that the high dislocation density at grain boundary can promote the nucleation of fcc→hcp transformation in Fe-based alloys.

关键词： martensitic transformation, stacking fault mechanism, nucleation, energy barrier, temperature, stress, dislocation density.

Zero Dissipation Limit to Rarefaction Waves for the 1-D Compressible Navier-Stokes Equations

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Chinese Annals of Mathematics,Series B 2012年第3期33卷 385-394页

作者： Feimin huang xing LI Academy of Mathematics and System Sciences Chinese Academy of SciencesBeijing 100190China

The zero dissipation limit for the one-dimensional Navier-Stokes equations of compressible,isentropic gases in the case that the corresponding Euler equations have rarefaction wave solutions is investigated in this *** a paper(*** ***.,46,1993,621-665) by ***,the author constructed a sequence of solutions to one-dimensional Navier-Stokes isentropic equations converging to the rarefaction wave as the viscosity tends to ***,he obtained that the convergence rate is ε 1/4 | ln ε|.In this paper,Xin's convergence rate is improved to ε1/3|lnε|2 by different scaling *** new scaling has various applications in related problems.

关键词： Compressible Navier-Stokes equations Rarefaction wave CompressibleEuler equations

C:N:P stoichiometry of perennial herbs’ organs in the alpine steppe of the northern Tibetan Plateau

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Journal of Mountain Science 2019年第9期16卷 2039-2047页

作者： MA xing-xing HONG Jiang-tao WANG Xiao-dan College of Geographical Sciences Shanxi Normal University Linfen 041000 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

The patterns of C:N:P stoichiometry across ecosystems are important in understanding biogeochemical processes. The stoichiometry of nutrients at the leaf and root level have been reported previously, but relationships of other plant organs, such as stems and the reproductive organs, remain unclear. We collected 228 samples of leaves, roots, stems and reproductive organs from 11 common plant species at 25 sites on the Tibetan Plateau to explore the relationships of C:N:P stoichiometry both within and across plant organs. The average C concentrations in the roots, leaves, stems and reproductive organs were 427.32, 410.51, 421.11 and 416.72 mg g-1, respectively. The shoot tissues(leaves, stems and reproductive organs) had significantly higher N and P concentrations than the roots. The N and P concentrations had a significant positive correlation within the same organ. The nutrient concentrations(N and P) and nutrient ratios(C:N, C:P and N:P) were significantly correlated across all pairwise organ combinations. Our data suggest that alpine perennial herbs share similar evolutionary histories and have constrained patterns of covariation for C concentrations, with differential patterns for N and P stoichiometry across organs. Our data also indicate that covarying sets of nutrient traits are consistent across environments and biogeographical regions and demonstrate convergent evolution in plant nutritional characteristics in extreme alpine environments.

关键词： Shoot tissues Chemical elements Biogeochemical process Alpine steppe Tibet Plateau

Homogenization of a Nonlinear Degenerate Parabolic Differential Equation

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Acta Mathematica Sinica,English Series 2013年第7期29卷 1429-1436页

作者： Hai tao CAO xing Ye YUE Department of Mathematics and Physics Changzhou Campus Hohai University Department of Mathematics Soochow University

This paper is devoted to the homogenization of a nonlinear degenerate parabolic problemwith Dirichlet boundary condition. Here the operator D（y, s, △s） is periodic in y and degenerated in △s. In the paper, under the two-scale convergence theory, we obtain the limit equation as ∈ → 0 and also prove the corrector results of △u^∈ to strong convergence.

关键词： Nonlinear degenerate parabolic equation homogenization two-scale convergence

On the leader-following exponential consensus of discrete-time linear multi-agent systems over jointly connected switching networks

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Control Theory and Technology 2023年第3期21卷 469-477页

作者： tao Liu Jie huang Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and TechnologyShenzhen 518055GuangdongChina Shenzhen Research Institute The Chinese University of Hong KongShenzhen 518057GuangdongChina Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina

The leader-following asymptotic consensus problem for general discrete-time linear multi-agent systems over jointly con-nected switching networks was solved about a decade ***,the leader-following exponential consensus was further established using the so-called Krasovskii-LaSalle theorem for a class of discrete-time linear switched *** this method involves some advanced concepts such as the weak zero-state detectability of some limiting *** this paper,we offer a simpler solution to the leader-following exponential consensus problem for general discrete-time linear multi-agent systems over jointly connected switching *** converting the solvability of the problem to the establishment of the exponential stability for a class of discrete-time linear switched systems,we first show that this class of linear switched systems is uniformly completely ***,we further conclude that the uniform complete observability for this class of linear switched systems implies the exponential stability for the same class of linear switched systems,thus leading to the solution of the leader-following exponential consensus ***,our approach also gives rise to an explicit characterization of the exponential convergence rate of the leader-following consensus problem.

关键词： Leader-following consensus Exponential stabilization-Linear switched systems Discrete-time systems

Harnack inequality and gradient estimate for G-SDEs with degenerate noise

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Science China Mathematics 2022年第4期65卷 813-826页

作者： xing huang Fen-Fen Yang Center for Applied Mathematics Tianjin UniversityTianjin300072China

In this paper,the Harnack inequality for G-SDEs with degenerate noise is derived by the method of coupling by change of the ***,for any bounded and continuous function f,the gradient estimate∣∇P_(t)f∣≤c(p,t)(Pt|f|p)^(1/p),p>1,t>0 is obtained for the associated nonlinear semigroup P¯*** an application of the Harnack inequality,we prove the existence of the weak solution to degenerate G-SDEs under some integrable ***,an example is *** of the above results extend the existing ones in the linear expectation setting.

关键词： Harnack inequality degenerate noise G-SDE gradient estimate weak solution invariant expectation

On the Unique Continuation Properties for Elliptic Operators with Singular Potentials

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Acta Mathematica Sinica,English Series 2007年第2期23卷 297-308页

作者： Xiang xing tao Song Yan ZHANG Department of Mathematics Faculty of ScienceNingbo University

Let u be a solution to a second order elliptic equation with singular potentials belonging to Kato-Fefferman-Phong＇s class in Lipschitz domains. An elementary proof of the doubling property for u^2 over balls is presented, if the balls are contained in the domain or centered at some points near an open subset of the boundary on which the solution u vanishes continuously. Moreover, we prove the inner unique continuation theorems and the boundary unique continuation theorems for the elliptic equations, and we derive the Bp weight properties for the solution u near the boundary.

关键词： doubling property unique continuation Lipschitz domain Kato-Fefferman-Phong's potential