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The Study on the Spatial Narrative in Jin Yucheng’s Flowers of Shanghai
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作者 CAO Xiaoxuan 《Cultural and Religious Studies》 2024年第10期641-647,共7页
Spatial narrative,as a unique literary narrative technique,focuses on advancing the plot and shaping characters through meticulous portrayal of space,providing readers with rich visual and perceptual experiences.This ... Spatial narrative,as a unique literary narrative technique,focuses on advancing the plot and shaping characters through meticulous portrayal of space,providing readers with rich visual and perceptual experiences.This paper examines the spatial narrative utilized in Jin Yucheng’s novel,Flowers of Shanghai.Through an in-depth analysis of the spatial narrative techniques in the novel,this paper asserts that such an exploration has far-reaching consequences in broadening research perspectives and fostering interdisciplinary collaborations between literature and geography.Furthermore,the paper explores the unique aspects of narrative perspective,narrative structure,and narrative time in Flowers of Shanghai,and how these elements perfectly combine with spatial narrative to create a fascinating literary world for readers.The aim of this study is to deeply explore the artistic value and literary charm of the novel through a comprehensive interpretation of the spatial narrative in Flowers of Shanghai. 展开更多
关键词 Flowers of Shanghai spatial narrative Jin Yucheng narrative strategy magical elements
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GEOMETRICALLY NONLINEAR FINITE ELEMENT MODEL OF SPATIAL THIN-WALLED BEAMS WITH GENERAL OPEN CROSS SECTION 被引量:11
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作者 Xiaofeng Wang Qingshan Yang 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第1期64-72,共9页
Based on the theory of Timoshenko and thin-walled beams, a new finite element model of spatial thin-walled beams with general open cross sections is presented in the paper, in which several factors are included such a... Based on the theory of Timoshenko and thin-walled beams, a new finite element model of spatial thin-walled beams with general open cross sections is presented in the paper, in which several factors are included such as lateral shear deformation, warp generated by nonuni- form torsion and second-order shear stress, coupling of flexure and torsion, and large displacement with small strain. With an additional internal node in the element, the element stiffness matrix is deduced by incremental virtual work in updated Lagrangian (UL) formulation. Numerical examples demonstrate that the presented model well describes the geometrically nonlinear property of spatial thin-walled beams. 展开更多
关键词 spatial beams thin-walled structures geometrically nonlinear finite element stiffness matrix
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The spatial distribution of major and trace elements of surface sediments in the northeastern Beibu Gulf of the South China Sea 被引量:5
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作者 Qian Ge George Z Xue +3 位作者 Liming Ye Dong Xu Jianru Zhao Fengyou Chu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第3期93-102,共10页
A multi-index analysis including grain size, major and trace elements is performed on the surface sediments from the northeastern Beibu Gulf to trace the sources of the sediments and to understand the controlling fact... A multi-index analysis including grain size, major and trace elements is performed on the surface sediments from the northeastern Beibu Gulf to trace the sources of the sediments and to understand the controlling factors for elements distribution. The mean grain size exhibits a wide variation ranging from 0.09Φ to 8.05Φ with an average value of 5.33Φ. The average contents of major elements descend in an order of c(SiO_2)>c(Al_2O_3)>c(Fe_2O_3)>c(CaO)>c(MgO)>c(K_2O)>c(Na_2O)>c(TiO_2)>c(P_2O_5)>c(MnO), while those of trace elements exhibit a descending order of c(Sr)>c(Rb)>c(V)>c(Zn)>c(Cr)>c(Pb)>c(Ni)>c(Cu)>c(As). On the basis of elementary distribution characteristics and statistical analyses, the study area is divided into the four zones: Zone I is located in the northeastern coastal area of the gulf, which receives large amount of fluvial materials from local rivers in Guangxi and Guangdong, China, and the Qiongzhou Strait; Zone Ⅱ is located in the center of the study area, where surface sediments exhibits a multiple source; Zone Ⅲ is located in the Qiongzhou Strait, where surface sediments are dominated by materials from the Zhujiang River and Hainan; Zone IV is located in the southwest of the study area, where surface sediments are mainly originated from the Red River and Hainan. The statistical analyses of sediment geochemical characteristics reveal that the grain size, which is mainly influenced by hydrodynamics and mineral composition of terrigenous materials, is the leading factor controlling the elementary distribution.Meanwhile, impacts from anthropogenic activities and marine biogenic process will also be taken into consideration. 展开更多
关键词 grain size major and TRACE elements Beibu GULF spatial distribution sediment source
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Temporal and Spatial Distribution of Elements in a Small Catchment, and Buffer Function of Wetland in Longgan Lake, China 被引量:7
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作者 吴艳宏 王苏民 +1 位作者 R.W.Barttarbee 朱育新 《Chinese Journal Of Geochemistry》 EI CAS 2004年第1期37-45,共9页
Wetland is the conjunction of lake and terrene where human activities are concentrated. From the viewpoints of material transport and cycling in the terrene-lake system, wetland is the buffer where sand and mud, heavy... Wetland is the conjunction of lake and terrene where human activities are concentrated. From the viewpoints of material transport and cycling in the terrene-lake system, wetland is the buffer where sand and mud, heavy metals, pollutants and nutrients are tarried. In this paper, we provide a case study based on the temporal and spatial distribution of elements in the Wangling River catchment, a small sub-catchment of Longgan Lake in the middle reaches of the Yangtze River. We have found that wetland can buffer major heavy metals such as Cr, Cu, etc. significantly, but has a little buffer function to some active elements such as Fe and Mn, which are always transported as solutions. Human activities not only influence the distribution of elements, but also weaken the buffer function of wetland. Intensive human activities in the Longgan Lake area in the past 70 years have been recorded in stream, wetland and lake sediments, especially the human activity events such as deforesting and reclaiming on a large scale in 1958 and the 1980’s. Human activities caused the increase of sedimentation rates since the 1950’s, as well as the increase of elements’ concentrations. The extensive use of fertilizers and pesticides since the 1960’s have led to the increase of total P concentrations. Increasing SO-2 emission accelerate the process of cation exchange in soil, and enhance the leaching of Mn out of soils. Permanent storing of water causes the soil gleyification that also intensifies the leaching of Mn. These are two major reasons for the obvious increase of manganese concentrations in recent 20 years in Longgan Lake. Intensive human activities since the 1950s’ have intensified the population in this region and thus destroyed the buffer function of wetland. 展开更多
关键词 沼泽地 河沙 淤泥 沉积 重金属
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Trace elements spatial distribution characteristics,risk assessment and potential source identification in surface water from Honghu Lake,China
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作者 LIU Chao-yang ZHANG Jing-dong +6 位作者 LI Fei) YANG Jun QIU Zhen-zhen CAI Ying ZHU Li-yun XIAO Min-si WU Zi-xian 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第7期1598-1611,共14页
Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were withi... Five trace elements including Zn, Cu, Cd, Cr and As were investigated in surface water from ten typical sampling sites in Honghu Lake. The consequence indicated that all of the detected trace element levels were within the allowed standard of China’s safe water guideline. The hazard quotients (HQ) and the hazard index (HI) value levels of all the five heavy metals in all sampling sites did not exceed the acceptable risk limits of non-carcinogenic value through the selected assessment method. Pearson’s correlation analysis and principal component analysis (PCA) indicated that Zn and Cu mainly originated from the natural alluviation and non-point agricultural sources, whereas Cr and As were mainly derived from industrial effluents. Moreover, Cd mainly originated from both non-point agricultural and industrial pollution sources. In addition, cluster analysis (CA) implied that cluster 1 (including S3, S5, S6 and S10) was considered the set of high pollution sites and cluster 2 (including S4 and S9) was identified as the set of moderate pollution sites. 展开更多
关键词 spatial distribution characteristic risk assessment source identification trace elements Honghu Lake
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Are spatial distributions of major elements in soil influenced by human landscapes?
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作者 Huan Yu Zhengwei He +1 位作者 Zeming Shi Bo Kong 《Acta Geochimica》 EI CAS CSCD 2018年第4期571-577,共7页
The present study attempted to evaluate the influence of human activity on major elements (Na2O, MgO, A1203, SiO2, K2O, CaO, Fe203), and to find a method to explore correlations between major elements and human dist... The present study attempted to evaluate the influence of human activity on major elements (Na2O, MgO, A1203, SiO2, K2O, CaO, Fe203), and to find a method to explore correlations between major elements and human disturbances, according to geospatial theories and methods. The study results indicate that landscapes influence major elements in diverse ways: Al2O3 is closely related to road and mine landscapes; strong relationships exist between MgO, Fe2O3, CaO, and SiO2 and roads; Na2O, SiO2, and Fe2O3 are unrelated to city landscapes; and Na2O is unrelated to road and mine landscapes. 展开更多
关键词 s Major elements spatial distribution Geographical background Human landscape Geographic information system Remote sensing
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A narratological analysis of spatial elements in The Metamorphosis
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作者 XU Ming-ying CUI Xiao-xi 《Sino-US English Teaching》 2010年第9期61-64,共4页
This paper discusses about the significance of space in the expression of the main themes in Kafka's novel The Metamorphosis. By applying Bal's basic narratology concepts on space, 2 spatial elements are analyzed in... This paper discusses about the significance of space in the expression of the main themes in Kafka's novel The Metamorphosis. By applying Bal's basic narratology concepts on space, 2 spatial elements are analyzed in the paper: the contrast of inside and outside, as well as the "filling in" of space, both of which serve to express human beings' isolation and desertion in an indifferent society. 展开更多
关键词 The Metamorphosis SPACE spatial elements NARRATOLOGY
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Research on Improvement of Utilization of Open Space: Through Demonstration Experiment Focusing on Spatial Elements
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作者 Yuka Kimura Yuichi Sueshige +2 位作者 Eisuke Aoki Yusuke Inaduka Hideaki Takayanagi 《Journal of Civil Engineering and Architecture》 2020年第3期153-159,共7页
Along with the rise of buildings, a large number of public open spaces have been created for the purpose of mitigating hatching restrictions and the like. However, many of them are used at low levels, and there remain... Along with the rise of buildings, a large number of public open spaces have been created for the purpose of mitigating hatching restrictions and the like. However, many of them are used at low levels, and there remain very few known public open spaces. In this research, we set up a resting place to demonstrate the effect of elements and placement in order to obtain knowledge for appropriately managing and utilizing such low use open public spaces. The survey means analyzed the presence/absence of the attraction/retention degree based on the cross-sectional traffic volume by video analysis and a hearing questionnaire survey for the users of the resting place. From the results, we have found that placement methods and effects that exceed the expectation value of each element, regionality, and attachment, occur by continuing experiments. 展开更多
关键词 PUBLIC open space low USAGE area REST area SOCIAL experiment spatial element.
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Preface for Special Issue:Single-Cell and Spatially Resolved Omics
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作者 Xiaohui Fan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第7期689-690,共2页
We are delighted to present you this special issue,which consists of a collection of articles focusing on the novel and rapidly evolving field of single-cell and spatially resolved omics.This encompasses epigenomics,t... We are delighted to present you this special issue,which consists of a collection of articles focusing on the novel and rapidly evolving field of single-cell and spatially resolved omics.This encompasses epigenomics,transcriptomics,proteomics,and metabolomics.Recent technological advances,coupled with computational techniques,have advanced the scope of this discipline to allow the investigation of individual cells down to an unprecedented level of detail.Researchers can now explore the cellular heterogeneity and the intricate interplay among its multiple molecular elements comprehensively. 展开更多
关键词 spatial spatially elementS
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Spatio-temporal variation of trace elements distributed over surface water of Upper Ganga River Basin in Western Himalayan Region
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作者 Deepika DIMRI Ambika KUMAR +1 位作者 DeepakKumar MISHRA Archana SHARMA 《Journal of Mountain Science》 SCIE CSCD 2023年第1期145-162,共18页
The rivers draining from the Himalayan range distribute enormous amount of fresh water to the people living in downstream regions.Trace metals flowed with river water can lead to serious impact on ecological system an... The rivers draining from the Himalayan range distribute enormous amount of fresh water to the people living in downstream regions.Trace metals flowed with river water can lead to serious impact on ecological system and human health.Nevertheless,the documentation on trace elements of Himalayan rivers is inadequately documented.The current study deals with the spatial and temporal variability of the major and trace elements of Ganga river water in epirhithron,metarhithron and hyporhithron zone belonging to Himalayan segment.Water samples from nineteen monitoring locations were collected in pre-monsoon(May-June),monsoon(AugustSeptember)and post-monsoon(December)seasons and subjected to be assessed for 20 elements(Ag,Al,Ba,Cd,Ca,Cr,Cu,Fe,Ga,K,Mn,Mg,Na,Ni,Pb,Sr,Th,U,Zn,and Zr)using ICP-OES(Inductively Coupled Plasma-Optical Emission Spectrometer).Different water pollution indexes such as HPI(Heavy Metal Pollution Index),MI(Metal Index)and PI(Pollution Index)were used to describe current water quality status at each monitoring station under particular classified ecological zone.The studied stations in hyporhithron zone had the value of Metal Index(MI>1),indicating threshold of warning.Further,the highest values of HPI in hyporhithron zone correspond to poor water quality status.Sites with poor water quality were also found to be contaminated as per the Pollution Index(PI),exhibiting high concentrations for element(Fe).However,the epirhithron and metarhithron zone in Himalayan segment showed excellent water quality mainly contributed from natural sources.Cluster Analysis(CA)and Principal Component Analysis(PCA)were applied to identify the main influential sources for Ganga river water pollution.The Kriging interpolation method was also applied to prepare spatial distribution map of computed indexes(HPI,MI,and PI).With the help of index of local Moran’s I(LMI),identified spatial clusters and spatial outliers revealed the elevated concentration of most elements in hyporhithron zone.The dataset presented in this study would be convenient for government officials in developing more effective management policies and necessary steps to check and monitor the Ganga river water quality.It was also suggested that further investigations in terms of trace elemental sources and their role in self-purification properties of Ganga water can be addressed in future. 展开更多
关键词 Trace elements spatial variation Temporal variation Surface water Ganga River Basin ICP-OES
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Stochastic analysis of excavation-induced wall deflection and box culvert settlement considering spatial variability of soil stiffness
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作者 Ping Li Shiwei Liu +2 位作者 Jian Ji Xuanming Ding Mengdie Bao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3256-3270,共15页
In this study, a three-dimensional (3D) finite element modelling (FEM) analysis is carried out to investigate the effects of soil spatial variability on the response of retaining walls and an adjacent box culvert due ... In this study, a three-dimensional (3D) finite element modelling (FEM) analysis is carried out to investigate the effects of soil spatial variability on the response of retaining walls and an adjacent box culvert due to a braced excavation. The spatial variability of soil stiffness is modelled using a variogram and calibrated by high-quality experimental data. Multiple random field samples (RFSs) of soil stiffness are generated using geostatistical analysis and mapped onto a finite element mesh for stochastic analysis of excavation-induced structural responses by Monte Carlo simulation. It is found that the spatial variability of soil stiffness can be described by an exponential variogram, and the associated vertical correlation length is varied from 1.3 m to 1.6 m. It also reveals that the spatial variability of soil stiffness has a significant effect on the variations of retaining wall deflections and box culvert settlements. The ignorance of spatial variability in 3D FEM can result in an underestimation of lateral wall deflections and culvert settlements. Thus, the stochastic structural responses obtained from the 3D analysis could serve as an effective aid for probabilistic design and analysis of excavations. 展开更多
关键词 Three-dimensional(3D) Geostatistical analysis Random finite element modelling(FEM) spatial variability of soil stiffness
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要素流动对城乡融合发展的影响机理与空间分异研究 被引量:4
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作者 平卫英 李文星 罗良清 《统计与信息论坛》 CSSCI 北大核心 2024年第6期15-31,共17页
城乡要素双向自由流动有利于提高要素配置效率和优化城乡关系,促进城乡融合发展。现有关于要素流动对城乡融合发展的研究主要围绕传统生产要素对城乡融合发展的研究展开讨论,鲜有文献将数据这一新型生产要素纳入城乡要素流动范围并探索... 城乡要素双向自由流动有利于提高要素配置效率和优化城乡关系,促进城乡融合发展。现有关于要素流动对城乡融合发展的研究主要围绕传统生产要素对城乡融合发展的研究展开讨论,鲜有文献将数据这一新型生产要素纳入城乡要素流动范围并探索其对城乡融合发展的影响机理。基于2010—2021年中国31个省份的面板数据,在测算要素流动、城乡融合发展水平的基础上,构建双向固定效应模型、地理加权回归模型和中介效应模型实证检验要素流动对城乡融合发展的影响效应及作用机制。研究发现:第一,全国要素流动总指数呈现出小幅度增长的态势,位于均值之上的地区中64%是城乡融合发展试验区,说明城乡融合发展政策实施具有重要的引导作用;第二,要素流动显著促进城乡融合发展,这一结论在引入城乡之间距离作为工具变量进行内生性检验、采用删除4个直辖市和缩短时间窗口的方法进行稳健性检验之后仍然成立;第三,空间异质性分析中,劳动力、土地和数据要素始终表现出促进城乡融合发展的作用,随着时间的推移,土地要素对不同地区城乡融合发展影响程度逐渐增强、影响范围逐步扩大,技术要素对城乡融合发展的促进逐渐凸现,由华东和华南地区向东北和西南地区转移;第四,在要素流动影响城乡融合发展的过程中,电商销售是要素流动影响城乡融合发展的重要途径,农业机械化和产业结构变迁并未发挥出中介变量的作用,不同于已有的研究结果。因此,今后持续深化城乡融合发展的内涵与外延、拓展深度与广度;始终以习近平新时代中国特色社会主义思想为指导,运用科学的世界观和方法论,坚持整体推进与试点示范相统一的指导原则,推广实践中形成的典型经验。研究结论为城乡要素双向合理流动的机制建立、城乡融合发展体制机制的健全提供了理论和经验上的参考。 展开更多
关键词 要素流动 空间异质性 城乡融合发展 政策演变 城乡关系
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软黏土地区深大基坑工程桩-连续墙体系空间变形效应 被引量:4
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作者 盛兴旺 林超 +3 位作者 郑纬奇 尹逊一 孙焕重 杨峰 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第2期591-601,共11页
土体开挖过程中深大基坑存在明显的空间变形效应,对其主体结构力学行为产生影响。以新建苏州南站枢纽深大基坑为工程背景,考虑地连墙厚度及工程桩的影响,基于ABAQUS建立三维空间有限元模型,采用修正剑桥模型考虑软黏土的应变硬化特征,... 土体开挖过程中深大基坑存在明显的空间变形效应,对其主体结构力学行为产生影响。以新建苏州南站枢纽深大基坑为工程背景,考虑地连墙厚度及工程桩的影响,基于ABAQUS建立三维空间有限元模型,采用修正剑桥模型考虑软黏土的应变硬化特征,从地连墙侧向位移、墙后地表沉降、工程桩和坑底土体隆起3个方面,研究软黏土地区深大基坑工程桩-连续墙体系的变形特征及空间效应。研究结果表明:深大基坑地连墙的侧向位移和地表沉降均呈现明显的角部效应,基坑A区(地连墙厚度1 m、桩径1 m)地连墙侧向位移角部效应的影响范围为1.05~1.71倍开挖深度,基坑B区(地连墙厚度0.8 m、桩径1.5 m)地连墙侧向位移角部效应的影响范围为0.91~1.48倍开挖深度;基坑A区、B区地表沉降角部效应的影响范围分别为1.24~2.10和1.77~2.47倍开挖深度;深大基坑空间变形角部效应与工程桩桩径及地连墙厚度有关,并且对基坑长边的影响效果大于短边。工程桩可有效增大基坑开挖面以下土体的刚度,减小地连墙的侧向位移;增大地连墙厚度可有效降低基坑的整体变形。基坑工程桩与坑底土体隆起总体呈现中间大、周边小的特征,工程桩周边土体受其约束,隆起较小;在一定范围内,工程桩对土体隆起抑制作用与其桩径呈正相关,与其桩间距呈负相关。软黏土地区深大基坑设计计算中需关注工程桩-连续墙结构体系的空间变形效应。 展开更多
关键词 深大基坑 软黏土地区 有限元 修正剑桥模型 空间变形效应
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数字经济助推中国产业转型升级——基于创新要素配置的中介效应 被引量:5
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作者 王薇 卫珂卉 《贵州财经大学学报》 CSSCI 北大核心 2024年第1期52-61,共10页
数字经济作为构建现代化产业体系的重要引擎,为赋能产业转型升级提供核心驱动力。区别于以往研究多从宏观视角考察数字经济对产业转型升级的直接影响,在对产业转型升级和数字经济发展水平测度框架进一步拓展完善的基础上,从创新要素配... 数字经济作为构建现代化产业体系的重要引擎,为赋能产业转型升级提供核心驱动力。区别于以往研究多从宏观视角考察数字经济对产业转型升级的直接影响,在对产业转型升级和数字经济发展水平测度框架进一步拓展完善的基础上,从创新要素配置这一微观视角,对数字经济影响产业转型升级的直接、间接作用机制及空间溢出效应进行了实证检验。研究发现:数字经济发展对产业转型升级具有显著的直接效应;数字经济通过人力和资本创新要素配置的中介效应正向促进产业结构高级化和绿色化,反向抑制产业结构合理化,且更多依赖资本创新要素的配置来影响产业转型升级;数字经济发展对产业转型升级的影响均具有空间溢出效应,并存在区域异质性。 展开更多
关键词 数字经济 创新要素配置 现代化产业体系 空间溢出效应
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从空间规划体系到国土空间体系——兼析国土空间体系构建下的国土空间治理趋向 被引量:5
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作者 林坚 张瑜 《中国土地科学》 CSSCI CSCD 北大核心 2024年第1期1-8,共8页
研究目的:分析国家治理体系和治理能力现代化背景下,国土空间体系表述的形成脉络及内在逻辑,并从国土空间体系构建视角探讨国土空间治理的未来趋向。研究方法:综合分析法与对比分析法。研究结果:国土空间具有“区域”和“要素”双重特性... 研究目的:分析国家治理体系和治理能力现代化背景下,国土空间体系表述的形成脉络及内在逻辑,并从国土空间体系构建视角探讨国土空间治理的未来趋向。研究方法:综合分析法与对比分析法。研究结果:国土空间具有“区域”和“要素”双重特性,建立空间规划体系旨在解决传统国土空间治理的“区域”“要素”缺乏统筹问题。从空间规划体系、国土空间规划体系到国土空间体系的演变,实质上是不断推进迈向高质量发展、强化“区域—要素”统筹的国土空间治理。在构建国土空间体系的指引下,国土空间治理既要聚焦国土空间的高质量发展,绘就国土空间协调发展蓝图,又要完善主体功能区战略和制度,做好国土空间治理的“区域—要素”统筹。研究结论:面向国土空间体系构建,国土空间治理未来应做好国土空间高质量发展导向下的“区域—要素”统筹治理。 展开更多
关键词 国土空间体系 国土空间治理 空间规划体系 国土空间规划体系 “区域—要素”统筹
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创新要素集聚对农业绿色技术进步空间溢出效应分析 被引量:2
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作者 张志新 妙丽英 《生态经济》 北大核心 2024年第1期103-110,共8页
基于2010—2020年中国31个省份的面板数据,采用空间杜宾模型实证分析创新要素集聚对农业绿色技术进步的空间溢出效应。研究结果表明:从全国来看,创新要素集聚对农业绿色技术进步的影响具有明显正向空间溢出效应,不仅驱动本地农业绿色技... 基于2010—2020年中国31个省份的面板数据,采用空间杜宾模型实证分析创新要素集聚对农业绿色技术进步的空间溢出效应。研究结果表明:从全国来看,创新要素集聚对农业绿色技术进步的影响具有明显正向空间溢出效应,不仅驱动本地农业绿色技术进步,还推动邻近地区农业绿色技术进步。创新要素集聚对农业绿色技术进步的空间溢出效应以短期效应为主。从区域来看,沿海、内陆地区创新要素集聚对农业绿色技术进步具有明显空间溢出效应,而沿边地区空间溢出效应不明显。对此,可改善创新要素引入制度、优化地区间创新要素互动机制、构建区域间农业绿色技术进步成果互通平台,持续促进农业绿色技术进步,以实现农业农村可持续发展。 展开更多
关键词 创新要素集聚 农业绿色技术进步 空间溢出效应 短期效应
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省域数字经济对共同富裕的影响研究--基于要素流动视角的空间计量检验 被引量:3
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作者 曹建飞 李凯 翟元慧 《河南科技学院学报(社会科学版)》 2024年第1期42-56,共15页
在信息化时代,数字经济如何促进共同富裕具有重要的现实意义。基于2011―2021年31个省份面板数据,测算数字经济指数和共同富裕指数,选取人才和资本要素流动为中介变量,数据要素流动环境为调节变量,运用空间杜宾模型(SDM)实证检验数字经... 在信息化时代,数字经济如何促进共同富裕具有重要的现实意义。基于2011―2021年31个省份面板数据,测算数字经济指数和共同富裕指数,选取人才和资本要素流动为中介变量,数据要素流动环境为调节变量,运用空间杜宾模型(SDM)实证检验数字经济发展对共同富裕的影响。结果表明:数字经济发展能明显促进共同富裕,对邻边地区存在显著的正向的空间溢出效应,且在地理分布上呈现明显的区域异质性。机制分析发现,数字经济能够通过人才和资本要素流动影响共同富裕;数字经济对共同富裕存在倒“U”型的非线性效应,且人才和资本要素流动对数字经济影响共同富裕起到“边际效应递增”作用;数据要素流动环境能合理调节数字经济对共同富裕的影响。据此,应大力发展数字经济,促进人才与资本要素的流动和精准匹配,形成优势互补、区域协调发展的新格局。 展开更多
关键词 数字经济 要素流动 数据要素流动环境 共同富裕 空间杜宾模型
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农田土壤有效态中量微量元素的时空变化特征研究
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作者 顾建芹 唐卫红 江健 《上海农业学报》 2024年第3期48-56,共9页
基于2019年的耕地地力调查监测点,分析农田土壤有效态中量微量元素含量及区域分布特征,结合分级标准和缺素临界值,揭示当前土壤中量微量元素丰缺状况;并对1983年、2004年的土壤的中微量元素有效态含量进行分析。结果表明:现阶段上海市... 基于2019年的耕地地力调查监测点,分析农田土壤有效态中量微量元素含量及区域分布特征,结合分级标准和缺素临界值,揭示当前土壤中量微量元素丰缺状况;并对1983年、2004年的土壤的中微量元素有效态含量进行分析。结果表明:现阶段上海市奉贤地区农田土壤有效态中量微量元素养分中Av-S含量为20—30 mg∕kg,Av-Si>300 mg∕kg,Av-Cu 4—6 mg∕kg,Av-Zn 2—3 mg∕kg,Av-Fe 100—150 mg∕kg,Av-Mn 30—40 mg∕kg,Av-B 0.75—1 mg∕kg,Av-Mo 0.1—0.15 mg∕kg,平均含量依次为20.04 mg∕kg、390.92 mg∕kg、4.31 mg∕kg、2.42 mg∕kg、131.08 mg∕kg、34.74 mg∕kg、0.95 mg∕kg和0.13 mg∕kg,分别处于土壤养分分级标准(5级)的第3、1、3、2、2、2、2、3级。这8种中微量元素变异系数均为中等变异强度,以Av-Fe(90.39%)最大。在1983年、2004年、2019年三个时间上,除Av-Mo含量整体变化较为平稳,缺素现象在不断加剧(目前缺素面积达73.68%)外,其余中微量元素在整体上有不同程度的增减,无缺素现象或缺素面积在减少。中量元素Av-S和Av-Si含量变化为一降一升,两者均在果园中高于其他土地利用方式;微量元素Av-Cu、Av-Fe、Av-Mn总体含量比较丰富,无低于临界值田块,在空间分布上为条状或斑状分布,呈自西往东逐渐减少格局,其菜地中的含量要低于粮田和果园;Av-Zn和Av-B含量在年际间不断提高,菜地中的含量普遍较高,区域分布上呈现相反趋势,Av-Zn为中部高东西部低,而Av-B为东西部高于中部。同时土壤多个微量元素间存在较高的相关性,Av-Cu、Av-Zn、Av-Fe、Av-Mn间表现出正相关性,它们也受土壤SOM和pH影响较大,其中Av-Cu受SOM、Av-Mn受pH作用最明显。研究结果可为本区不同土地利用方式及区域分布的土壤养分管理和中微肥合理搭配提供依据。 展开更多
关键词 中量元素 微量元素 时间变化 空间分布 土地利用方式
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成渝地区双城经济圈数字化要素对产业结构升级的空间效应
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作者 陈堂 陈光 陈鹏羽 《科技管理研究》 CSSCI 2024年第12期85-93,共9页
数字要素赋能已成为成渝地区双城经济圈产业升级的新途径,然而,目前缺乏对其在地理、经济和数字新型基础设施建设(以下简称“新基建”)等距离特征条件下数字化要素产生的空间效应的深入研究。为对成渝地区双城经济圈产业高质量发展在政... 数字要素赋能已成为成渝地区双城经济圈产业升级的新途径,然而,目前缺乏对其在地理、经济和数字新型基础设施建设(以下简称“新基建”)等距离特征条件下数字化要素产生的空间效应的深入研究。为对成渝地区双城经济圈产业高质量发展在政策层面提供理论支持,从数字化创新环境、数字化创新技术、数字化人力资本、数字化劳动力、数字化资本等维度构建数字化要素评价体系,选取2012—2021年成渝地区双城经济圈的空间面板数据,基于地理、经济和数字新基建距离特征建立内生增长模型,运用空间计量模型实证分析成渝地区双城经济圈数字化要素和产业结构升级的关系。结果表明:成渝地区双城经济圈数字化要素和产业结构升级具有禀赋差异特征和时空集聚特征,且域间集聚差异在逐步扩大,3种距离特征下“成都+重庆”中心城市产业呈现出显著的生态化、集群化和丛林化特征,其他地区产业发展呈现出显著的专业化特征,对中心城市的空间依赖性越来越强。赋能产业结构升级方面,3种距离特征下,数字化要素对域内带来空间效应、对域外带来空间外溢效应,资源禀赋对域内具有空间促进作用、对域外具有空间抑制作用;在地理距离特征条件下,数字化技术创新对域外具有空间抑制作用;在数字新基建距离特征条件下,数字化人力资本具有空间抑制作用。此外,动态空间面板模型可以修正静态空间面板模型产生的过高空间估计误差。据此,建议加强成渝两极协同发展,形成两地产业的梯度化分工格局,实现成渝“双核”驱动相邻区域发展。 展开更多
关键词 数字化要素 数字赋能 产业结构升级 距离特征 空间效应 空间计量模型 区域创新发展 成渝地区双城经济圈
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基于Barker码脉冲压缩技术的钢板多阵元Lamb波电磁超声换能器设计与优化
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作者 石文泽 李淇鑫 +2 位作者 卢超 胡博 刘远 《电工技术学报》 EI CSCD 北大核心 2024年第8期2371-2387,共17页
为了解决传统Barker码脉冲压缩技术受脉冲功率放大器额定参数(占空比,最大脉冲宽度等)限制而导致的脉冲压缩效果下降、检测速度降低等问题,提出一种基于Barker码脉冲压缩技术的多阵元Lamb波电磁超声换能器(EMAT)。建立了基于tone-burst... 为了解决传统Barker码脉冲压缩技术受脉冲功率放大器额定参数(占空比,最大脉冲宽度等)限制而导致的脉冲压缩效果下降、检测速度降低等问题,提出一种基于Barker码脉冲压缩技术的多阵元Lamb波电磁超声换能器(EMAT)。建立了基于tone-burst信号激励-Barker码脉冲压缩技术的多阵元Lamb波EMAT检测过程的有限元模型,分析了永磁体的配置形式、阵元序列长度、激励信号周期数、曲折线圈匝数等因素对脉冲压缩后的主旁瓣比和主瓣宽度的影响,并进行了实验验证。结果表明:曲折线圈匝数为4和Barker码序列长度为13位的多阵元EMAT在配置3对外置永磁体后,其信噪比(SNR)可提高9.8 dB。综合考虑检测回波的空间分辨率和SNR,多阵元Lamb波EMAT最佳参数为:曲折线圈匝数为10、激励信号周期数为11、Barker序列为13位,并配置3对外置永磁体。 展开更多
关键词 电磁超声换能器 Barker码脉冲压缩 多阵元Lamb波EMAT 信噪比 空间分辨率
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