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Spatial evolution and spatial production of traditional villages from "backward poverty villages" to "ecologically well-off villages": Experiences from the hinterland of national nature reserves in China

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Journal of Mountain Science 2024年第4期21卷 1100-1118页

作者： Zhang yiyi LI Yangbing College of Geography and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China

With the rapid urbanization process,the space of traditional villages in China is undergoing significant *** the spatial evolution of traditional villages is significant in promoting rural spatial transformation and realizing rural revitalization and sustainable rural *** on the traceability analysis of spatial production theory,this paper constructed an analytical framework for the spatial production evolution of traditional villages,analyzed the spatial evolution process and characteristics of traditional villages by using buffer analysis,spatial syntax,and other research methods,and revealed the characteristics of the spatial production evolution of traditional villages and the driving *** results show that:(1)The village spatial formation and development follow the village life cycle theory and usually develop from embryonic villages to diversified and integrated villages;(2)The evolution of village spatial production is characterized by the diversity of material space,the sublimation of daily life space,and the integration of social system space and generalization of emotional space;(3)The evolution of village spatial production from backward and poor village to ecologically well-off village is influenced by a combination of factors;(4)The village has formed a spatial structure of"people-land-scape-culture-industry",realized comprehensive reconstruction and spatial *** study results reflect the spatial evolution characteristics of traditional villages in mountainous areas in a more comprehensive way,which helps to promote the protection and development of traditional villages in mountainous areas and,to a certain extent,provides a reference for the development of rural revitalization.

关键词： Traditional villages Spatial production Spatial evolution Spatial reconstruction

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求解高光谱解混的三算子分裂方法

郑州大学学报(理学版) 2025年第2期57卷 85-88页

作者：董云达张园园李一怡郑州大学数学与统计学院

对于高光谱解混问题，提出了一个相应的三算子单调包含和求解该问题的一个分裂方法，其中邻近因子可以自适应选取。该方法还可用于求解更一般的带有线性复合的三算子单调包含问题。数值实验表明，该算法的性能远远超过最近提出的邻近内... 详细信息

对于高光谱解混问题，提出了一个相应的三算子单调包含和求解该问题的一个分裂方法，其中邻近因子可以自适应选取。该方法还可用于求解更一般的带有线性复合的三算子单调包含问题。数值实验表明，该算法的性能远远超过最近提出的邻近内点方法，并且与其变尺度版本相当。

关键词：邻近内点法单调包含分裂方法高光谱解混自适应

Cretaceous Phytoplankton Assemblages from Songke Core-1,North and South(SK-1,N and S) of Songliao Basin,Northeast China

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 868-874页

作者： ZHANG yiyi BAO Lina China University ofGeosciences （Beijing） Beijing 100083 Jilin Technology College of Electronic Information Jilin 132021

Cretaceous phytoplankton from the newly completed core hole （SK-1, N＆S） in the central Songliao Basin was studied. The target interval is from the upper Quantou Formation of Upper Cretaceous to Mingshui Formation. Twelve genera of dinoflagellates, six of acritarcha and three of chlorophyta were identified in 588 samples from the 2300-m deep core. Ten phytoplankton assemblages have been classified： ***, Botryococcus- Pediastrum, Pediastrum, Dinogymniopsis-Chlamydophrella-Vesperopsis bifurcate, Dinogymniopsis minor-Balmula, ***, Schizosporis-Campenia, ***- Botryococcus, Dinogymniopsis-Granodiscus-Filisphaeridium and Granodiscus. According to the findings mentioned above, the age of the upper Qantou Formation is Cenomanian, the Qingshankou Formation belongs to upper Cenomanian-Turonian, the Yaojia Formation to Coniancian-Santonian age, the Nenjiang Formation is of Campanian age, and Sifangtai-Mingshui formations are referred to Maastrichtian stage. The ecology of phytoplankton is closely related to water salinity. Each type of phytoplankton is within a certain living water mass whose evolution type reflects salinity change of the Songliao Lake. The assemblages from the SK-1 indicate that water salinity changes with the cycle of freshwater-slight brackish water-brackish water-slight brackish water-freshwater in the lake.

关键词： phytoplankton assemblage salinity Cretaceous Songke-1 Songliao Basin

Modular handover algorithm for 5G HetNets with comprehensive load index

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The Journal of China Universities of Posts and Telecommunications 2017年第2期24卷 57-65页

作者： Li Danyang Zhang Zhizhong Gao yiyi Chongqing Key Laboratory of Communication Networks and Testing Technology Chongqing University of Posts and Telecommunications

Most existing handover decision system （HDS） designs are monolithic, resulting in high computational cost and unbalance of overall network. A novel modular handover algorithm with a comprehensive load index for the 5th generation （5G） heterogeneous networks （HetNets） is proposed. In this paper, the handover parameters, serving as the basis for handover, are classified into network＇s quality of service （QoS） module, user preference （UP） module and degree of satisfaction （DS） module according to the new modular HDS design. To optimize switching process, the comprehensive network load index is deduced by using triangle module fusion operator. With respect to the existing handover algorithm, the simulation results indicate that the proposed algorithm can reduce the handover frequency and maintain user satisfaction at a higher level. Meanwhile, due to its block calculation, it can bring about 1.4 s execution time improvement.

关键词： 5G HetNets handover modular HDS comprehensive load index

Modeling of Solidification Microstructures Based on Fully Coupling of Macro-transport Phenomena with Cellular Automata

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Journal of Materials Science & Technology 2000年第6期16卷 568-572页

作者： Qiang DU DianZhong LI yiyi LI Institute of Metal Research Chinese Academy of SciencesShenyang 110015China

This paper has attempted to simulate the microstructure formation based on fully coupling of temperature field, concentration field and velocity field with micro-kinetics. The authors presented a new way, which is the combination of FDM and cellular automata (CAFD) to visualize the microstructure formation of the thin complex superalloy turbine blades cast by the vacuum investment process. The distribution, orientation and mechanism of the heterogeneous nucleation, the growth kinetics of dendrites and the columnar to equiaxed transition (CET) are considered. Capitalizing on these simulating schemes, the comprehensive influence of key process variables on the scale and uniformity of grains has been investigated quantitatively. The simulated grain size and morphology agree well with the experimental results.

关键词： Microstructure

Research on the Relationship between Fiscal Expenditure and Educational Equity

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学术界 2016年第7期 319-324页

作者： Ouyang yiyi School of Economics and Management Wuhan University Wuhan Hubei 430072

Educational equity is important foundation to achieve social equity and to build a harmonious society,and fiscal expenditure is an important means for the government to allocate resources. However,educational inequity is very common in China at present. Through logical analysis of the relationship between the fiscal expenditure and the educational equity in this paper,it is found that the insufficiency of total fiscal expenditure is the main reason for educational inequity at the present stage; the total fiscal expenditure on education shows positive correlation with the educational equity; the optimization degree of the structure of the fiscal expenditure on education shows positive correlation with the educational equity. Therefore,the government shall expand the scale of the fiscal expenditure on education and optimize the structure of the fiscal expenditure on education.

关键词：教育支出财政支出结构优化社会公平逻辑分析政府正相

Precipitation Behavior and Mechanical Properties of a 16Cr-25Ni Superaustenitic Stainless Steel Weld Metal During Post-weld Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 577-590页

作者： Wenbin Tian Dong Wu yiyi Li Shanping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

A 16Cr-25Ni superaustenitic stainless steel weld metal for austenitic stainless steel/ferrite heat-resistance steel dissimilar metal weld was designed and prepared through tungsten inert-gas *** precipitate evolution and its correlation with mechanical properties were investigated during post-weld heat treatment(PWHT)at 690℃ for up to 12 *** primary precipitates in the as-welded weld metal were identified as Mo-rich M6C carbides in the interdendritic region and semicontinuous fine-sized M23C6 carbides along grain *** PWHT,three types of precipitates coexisted in the interdendritic region:primary M6C carbides,newly precipitated Mo-rich M2X carbonitrides and some of the secondary M23C6 ***,mass secondary M23C6 carbides formed and coarsened along grain *** undesirable intermetallic phases formed during the whole *** M2X and interdendritic M23C6 improved the strength of the weld metal after PWHT,but the elongation and impact toughness degraded,which were mainly owing to the intergranular M23C6 carbides that changed the fracture mode from ductile transgranular mode to mixed mode of transgranular and intergranular ***,the coarsening of M2X carbonitrides may lead to the elongation loss during 8 h to 12 *** of impact toughness was also related to the M2X carbonitrides,which made the crack easier to propagate compared with austenitic matrix and contributed to the decline of impact ***,due to the sluggish precipitation of M2X carbonitrides with longer holding time,the decreasing trend became slow from 4 to 12 *** results showed that PWHT should be controlled within 8 h to obtain better combination of strength and ductility.

关键词： Superaustenitic stainless steel Weld metal Post-weld heat treatment Precipitate evolution Mechanical properties

Multi-scale study on the heterogeneous deformation behavior in duplex stainless steel

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Journal of Materials Science & Technology 2021年第13期72卷 180-188页

作者： Xiao Zhang Pei Wang Dianzhong Li yiyi Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The heterogeneous deformation behavior of austenite and ferrite in the 2205 duplex stainless steel was subjected to multiscale analysis based on the in situ synchrotron-based high energy X-ray diffraction,microscopic digital image correlation,electron backscatter diffraction,and transmission electron *** is found that the heterogeneous deformation triggers from the yielding of *** this deformation stage,austenite experiences greater strain in the area near the phase boundaries because of the impeded function of the phase boundaries to *** to the relatively small difference in hardness between the constituent phases,the strain in austenite grains extends into the adjacent ferrite grains when entering into the ferrite yielding *** addition,the strain distribution of the austenite grains is more homogeneous than that of the ferrite grains because of the lower stacking fault energy of austenite,which results in a planar slip,and higher stacking fault energy in case of ferrite,causing cross *** interaction between austenite and ferrite becomes considerably obvious when the strain further increases after both constituent phases yielding because of the back stress and forward stress in austenite and ferrite,respectively,which are generated by the pile-up of the geometrically necessary dislocations.

关键词： Duplex stainless steel Heterogeneous deformation behavior Digital image correlation Back stress Geometrically necessary dislocation

Microstructural evolution and stress relaxation cracking mechanism for Super304H austenitic stainless steel weld metal

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Journal of Materials Science & Technology 2022年第5期100卷 82-90页

作者： Xiaopeng Xiao Dianzhong Li yiyi Li Shanping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Insititute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The pre-compressed CT technique was used to quantitatively investigate the formation of stress relaxation cracks under different tensile residual stresses and aging time in Super304H austenitic stainless steel weld *** statistical results revealed that intergranular cracks could occur within 2000 h under 650℃ when the residual stress was applied with greater than 18 KN pre-compression *** grain interior and boundary analyses showed that the growth of intragranular Cu-rich particles could induce a strong grain interior,and the intergranular Nb(C,N)carbides were one of the causes to crack under short-term aging *** long-term aging time conditions,the intergranular M_(23)C_(6)carbides were more susceptible to crack than intergranular Nb(C,N)***,the mechanism responsible for stress relaxation cracking formation was carefully illustrated for the weld metals after short-term aging and long-term aging,respectively.

关键词： Stress relaxation cracking Super304H steel Weld metal Aging treatment Residual stress Precipitates