Temporal and spatial differences in human activities performed in Urban Green Spaces of Vilnius(Lithuania)

Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,weekly,and daily use of three urban green spaces(Vingis Park,Bernardino Garden,and Jomantas Park)in Vilnius(Lithuania).The study is based on an on-site observation-based survey,which recorded users’characteristics,activities,and weather conditions during summer and winter.The results showed that UGS’s seasonal,weekly,and daily use differed according to park and users’characteristics.Parks with a higher diversity of facilities had a high seasonal difference in the number of observed activities.User numbers were higher in the summer for activities with children,social activities,sports,and water activities than in the winter.Jomantas Park had the lowest variability in user characteristics.Weather variables were linked to changes in users’activities.Higher precipitation and lower temperature were associated with reducing the number of users and the diversity of registered activities.Most of the stationary activities were observed during summer.The diversity of the observed activities was associated with the available facilities rather than the park size.The distribution of stationary activities was spatially correlated with facility/equipment(benches,playgrounds,sports,and fitness equipment)and proximity to water features.The results of this study are relevant for UGS design,planning,and management.

Spatial-temporal differences in in-stream flow requirement based on GIS： A case study of Yan＇an region, northern Shaanxi

Although water has the central function of the bloodstream in the biosphere especially in arid or semi-arid regions such as Yah＇an region in northwestern China, yet the very limited attention is paid to the role of the water-related processes in ecosystem. In this research, based on continuous nearly 50-year data including runoff volume, sediment discharge as well as sediment accretion from hydrographic stations, and 10-year information of water quality from pollution monitoring stations, the method for measuring in-stream flow requirement has been put forward supported by experiential models and GIS spatial analysis. Additionally, the changes of in-stream flow requirement for environment and economic development have been addressed from spatial-temporal dimensions. The results show that： （1） According to the central streams in Yan＇an region, mean annual in-stream flow requirement reaches 1.0619 billion m^3, and the surface water for economic exploitation is 0.2445 billion m3 （2） Mean annual in-stream flow requirement for sediment transfers in flood period occupies over 80% of the integrated volume in a year. （3） From the 1950s to 1970s, in-stream flow requirement for sediment transfers is comparatively higher, while from the 1980s to 1990s, this requirement presents a decreasing tendency.

Temporal-spatial change and driving mechanism for regional difference of domestic tourism in China

By using the variation coefficient,Gini coefficient and Theil coefficient,this paper makes preliminary exploration of temporalspatial change features and driving mechanism for regional differences of domestic tourism in China from 1995 to 2009.According to the results,we drew the following conclusions:(1)The regional difference of domestic tourism in China tends to be narrowing generally,and is less than that of inbound tourism,playing an important role in narrowing the overall gap of regional tourism in China.(2)The regional internal difference features:inter-provincial difference in the eastern region and difference among the eastern,central and western regions are comparatively obvious and demonstrate a significantly shrinking tendency,the change tendency is consistent with the change tendency of overall difference and exercises a decisive role in overall difference,whereas the inter-provincial difference in the central and western regions is small and relatively stable,having less influence on the overall difference.(3)The temporal-spatial change in regional difference is featured by:low-level provinces occupy a majority and are concentrated in the central and western regions,showing a tendency of narrowing difference;high-level provinces are concentrated in the eastern region,showing a tendency of spreading to the central and western regions;spatial pattern of regional difference demonstrates 4 types,i.e."proliferation type","polarization type","quiescence type"and"collapse type."(4)The driving force for regional difference of domestic tourism in China comes down to 3 aspects:regional socio-economic attribute,regional transport accessibility level and regional development policy.

Exploration on Temporal-spatial Difference of Cultivated Land Pressure and Influence Factor Analysis: A Case Study of Guangxi

Based on related statistical data during 1980-2014,change rule of Guangxi cultivated land pressure level was studied. Taking each municipal administrative division as evaluation unit,temporal-spatial change trend of cultivated land pressure level was explored by establishing pressure index model of cultivated land,and principal component analysis was used to explore the driving force of cultivated land pressure. Results showed that from 1980 to 2014 in Guangxi,cultivated land pressure was at level one in 12 years,level two in 19 years and level three in 4 years; mean of cultivated land pressure in each city during 2005-2014 was taken as average level of cultivated land pressure in the city,in which cultivated land pressure values of Chongzuo City,Baise City,Laibin City,Liuzhou City,Fangchenggang City,Nanning City,Hechi City and Guigang City were all lower than average level in Guangxi at the same period. Driving factors of cultivated land pressure index mainly contained urbanization rate,Engel coefficient of rural households(ECRH),per capita cultivated land area,total population and rural per capita net income(RPFI).

Spatial and Temporal Differences of Urban Land Comprehensive Carrying Capacity in Guangxi

The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land comprehensive carrying capacity was constructed from the 4 aspects of resource, economy, society, environment, and principal component analysis and cluster analysis were used to evaluate the urban land comprehensive carrying capacity of Guangxi and the 14 cities in 2005-2014, and analyzed its spatial and temporal characteristics as well as the driving forces, with the aim to provide references for improving the urban land comprehensive carrying capacity. The results showed that, the overall urban land comprehensive carrying capacity in Guangxi increased in 2005-2014, and there were significant differences in the land comprehensive carrying capacities among the cities in Guangxi in 2005-2014, in which Liuzhou, Guilin, Nanning belonged to the regions with the highest carrying capacity, while Beihai, Yulin, Wutong belonged to the regions with high carrying capacity, and the carrying capacities of the other cities changed with the changes of time. The economic development degree was an important factor influencing urban land comprehensive carrying capacity, but could not directly represent the urban land comprehensive carrying capacity level.

TEMPORAL AND SPATIAL DIFFERENCES OF THE INDUSTRIAL RESTRUCTURING OF GUANGDONG PROVINCE IN THE 1990S

This paper focuses on the temporal and spatial change of industrial structure in Guangdong Province since the 1990s. The attention is initially paid to the change of industrial structure through analyzing the structure change of the three sectors, and the change of internal structures of agriculture, industry and tertiary sector respectively. Then the spatial differences of industrial restructuring are analyzed based on the four economic regions which have been agreed in the academic field: the Zhujiang(Pearl) River Delta, northern mountain region, east and west wings. Thirdly, the reasons for the spatial differences of industrial restructuring are examined. Finally a short conclusion is drawn and some suggestions for the regional integration are put forward.

Temporal and spatial study of differently charged ions emitted by ns-laser-produced tungsten plasmas using time-of-flight mass spectroscopy

Tungsten(W)is an important material in tokamak walls and divertors.The W ion charge state distribution and the dynamic behavior of ions play important roles in the investigation of plasma–wall interactions using laser-ablation-based diagnostics such as laser-induced breakdown spectroscopy and laser-induced ablation spectroscopy.In this work,we investigate the temporal and spatial evolutions of differently charged ions in a nanosecond-laser-produced W plasma in vacuum using time-of-flight mass spectroscopy.Ions with different charge states from 1 to 7(W+to W7+)are all observed.The temporal evolutions of the differently charged ions show that ions with higher charge states have higher velocities,indicating that space separation occurs between the differently charged ion groups.Spatially-resolved mass spectroscopy measurements further demonstrate the separation phenomenon.The temporal profile can be accurately fitted by a shifted Maxwell–Boltzmann distribution,and the velocities of the differently charged ions are also obtained from the fittings.It is found that the ion velocities increase continuously from the measured position of 0.75 cm to 2.25 cm away from the target surface,which indicates that the acceleration process lasts through the period of plasma expansion.The acceleration and space separation of the differently charged ions confirm that there is a dynamic plasma sheath in the laser-produced plasma,which provides essential information for the theoretical laser-ablation model with plasma formation and expansion.

时间-空间高阶精度矩形交错网格隐式有限差分声波正演模拟

有限差分方法因其操作简单、计算消耗低而成为地震勘探领域中最为常用的数值模拟方法之一,然而用离散的显式差分算子数值逼近地震波动方程中的连续导数容易导致数值频散,并且基于正方形网格离散形式的有限差分方法对不同地质模型的适应性较低.针对一阶变密度声波方程的数值模拟,本文发展了一种适用于矩形网格离散形式的时间高阶空间隐式有限差分格式,可以有效压制时间和空间频散,同时灵活的网格剖分增强了其应用的广泛性.基于本文矩形交错网格时间高阶空间隐式有限差分格式的时空域频散关系和变量替换的思想,首先采用泰勒级数展开方法求解不同方向的非轴上时间差分系数及轴上空间差分系数,使本文差分格式可以获得任意偶数阶时间和空间精度.为了进一步提高本文差分格式在更大波数区域的空间模拟精度,我们采用线性优化方法来求取新的轴上空间差分系数用于一阶变密度声波方程的波场迭代求解中.频散、稳定性分析及数值模拟算例表明:相比于传统十字形空间域隐式有限差分格式,本文矩形交错网格时间高阶空间隐式有限差分格式在精度、稳定性和效率方面均具有优势.

Regional Differences of China′s Urban Expansion from Late 20th to Early 21st Century Based on Remote Sensing Information

This study investigated the regional differences of China′s urban land expansion from the late 1980s to the year of 2008, based on the spatio-temporal analysis of CLCD (China′s land cover/land use database) datasets which were mainly produced from remote sensing imagery data. A newly defined urbanization level index (UI), based on urban land area, is proposed to describe Chinese urban expansion process at 1 kilometer, provincial, regional, and na-tional scales, together with the absolute urban expansion index (UEa) and the relative urbanization expansion index (UEr). The results indicate that the percentages of total land area occupied by urban in the late 1980s, 1995, 2000, 2005, and 2008 were approximately 0.25%, 0.32%, 0.33%, 0.43% and 0.52% of China′s total land area, respectively. Between the late 1980s and 2008, the total urban expansion in the mainland of China was 2.645 × 104 km2, resulting in an annual urban expansion area of about 1322.7 km2/yr, with the UEr of 111.9%. This study also finds that there has been an obvious spatial gradient of urbanization ratio running from the east coast to the west inland, and the urbanization gaps among different regions have persisted over the past two decades. The study also reveals obvious temporal varia-tions of the urbanization rates. There was very little urban growth during the period of 1995-2000 due to the governmental policy factors.

数字乡村发展水平指标体系构建与实证研究--以河南省2014-2021年18个地级市面板数据为例

【目的】科学量化数字乡村发展水平,有效推进现代信息技术与乡村各领域全面有机融合,助力乡村振兴。【方法】在梳理学界最新研究成果以及实践调研的基础上,基于2014-2021年河南省18个地市面板数据,从乡村数字信息基础、乡村数字经济新业态、农业数字化转型、乡村生活数字化4个维度选取20个指标,构建数字乡村发展水平评价指标体系。综合运用熵权法、TOPSIS法、Kernel密度估计、泰尔指数、Moran’s I等研究方法测度河南省数字乡村发展水平,分析其区域差异及时空演变规律。【结果】(1)从发展水平看,考察期内河南省数字乡村发展水平呈现逐年上升态势,虽然整体发展水平不高,但可持续发展动能强劲。(2)从区域差异看,河南数字乡村发展水平整体差异呈现稳步下降趋势。其中,区域间差异对总体差异的贡献最大,中原城市群与黄淮地区差异最明显,区域内差异表现为中原城市群、豫西豫西南、豫北、黄淮地区依次递减的态势。(3)从时空演变看,四大经济区区域间呈现明显且稳定的正相关,中原城市群地市多表现为高高集聚,而黄淮地区基本表现为低低集聚。【结论】河南省数字乡村发展应该结合省情及区域特征,全面布局、统筹推进、均衡发展、弥合差距、快速提升。

长江经济带土地利用与经济-社会-环境耦合协调研究

[目的]测算长江经济带城市土地利用与经济—社会—环境系统的耦合协调度,并考察其时空分异特征及驱动因素,进而为长江经济带土地可持续利用和区域高质量协调发展提供决策参考。[方法]基于2006—2019年长江经济带108个地级市的面板数据,构建了土地利用与经济—社会—环境系统的指标体系,采用熵权法、耦合协调度模型测算耦合协调度,并借助Dagum基尼系数、莫兰指数和地理加权回归模型进行时空分异特征及驱动因素分析。[结果]2006—2019年长江经济带土地利用与经济—社会—环境耦合协调度由0.309上升至0.477,从轻度失调转入勉强协调。不同区域间的耦合协调度由下游区域向上游区域逐步递减,呈现“东高西低”的空间分布格局。耦合协调度的总体、区域内和区域间差异呈现下降趋势。区域间差异是总体差异的主要原因,其贡献率由43.67%上升至46.88%。耦合协调度的Moran's I值由0.095上升至0.134,具有显著的空间正自相关性,“H—H”集聚区主要分布在下游区域,“L—L”集聚区主要分布在中上游区域。地形起伏和坡度呈现负向驱动,城镇化水平和外商直接投资呈现正向驱动,人口密度呈现两级化驱动特征。[结论]长江经济带土地利用与经济—社会—环境的耦合协调度存在时空异质性,应充分考虑区域特征制定差异化的土地利用政策。

中国城市碳排放绩效:动态分解、空间差异与影响因素

以非径向方向距离函数为框架,构造全要素碳排放绩效指数对中国2006—2019年城市碳排放治理绩效进行测度。在此基础上从经济含义、跨期动态变化、区域均衡等层面对全要素碳排放绩效指数进行多维分解,检验中国城市碳排放绩效的影响因素。结果表明:第一,样本期内全国城市平均全要素碳排放绩效指数总体呈波动上升态势,动态分解结果显示,中国各地的平均碳排放绩效水平不断改进,创新效应对其贡献逐年增大但赶超效应贡献不足;第二,空间分异方面,珠三角、长三角、粤闽浙沿海、长江中游等东部地区城市群不仅平均碳排放绩效水平普遍较高,且碳排放绩效的增长速度较快,中西部地区仅成渝城市群碳排放绩效表现较好,中原、京津冀等城市群近年来碳排放绩效的改善速度较快;第三,基尼系数测度及其分解显示,近年中国城市碳排放绩效指数的分异程度逐步加深,分异成因主要为城市群组间差异,城市群内部差异贡献度较低;第四,Lasso分析及双固定面板模型分析结果显示,经济发展水平、清洁能源使用、金融发展、绿色环保和科技支持能够有效改善城市层面的碳排放绩效,能源消耗强度和第二产业就业人员比重对碳排放绩效具有负面影响;最后,城市群因子探测结果显示,各城市群间的驱动因子存在一定差异。

中国数字经济发展水平时空演变及区域差异分析

数字经济作为国民经济的核心增长极之一,正在成为促进经济发展的新动能。构建数字经济发展水平指标体系,运用熵值法对2014—2020年中国省际数字经济发展水平进行测度,在此基础上进一步探究中国数字经济发展的分布动态和区域差异。研究结果表明:与2014年相比,2020年中国数字经济发展水平整体有所提升,分区域看,东部地区数字经济发展水平呈波动下降趋势,中西部地区呈上升趋势且差距较小;空间分布上,中国数字经济呈现东高西低的发展格局,而且在发展过程中逐步形成多极分化状态;东、中、西地区数字经济发展的相对差异呈不断缩小趋势,并且区域内差异是造成数字经济发展存在差异的主要原因。

2000-2019年国家自然科学基金医学领域经费投入区域差异及时空格局演变分析

目的:分析国家自然科学基金医学领域经费投入区域差异及时空分布格局变化情况,为优化科学基金区域布局和推动医学科学区域创新均衡协调发展提供参考。方法:基于国家自然科学基金医学领域资助项目数据,综合运用变异系数、区位基尼系数、空间自相关、自然间断点分级法、空间集中度等多元分析方法探讨医学科研投入的地域分布差异、空间格局及其变动情况。结果:国家自然科学基金医学领域项目资助数量与金额分别从2000年的607项、1.28亿元增至2019年的10 192项和46.47亿元;从区域层面来看,国家自然科学基金医学领域经费投入集中于华东和华北地区,其累计占比由2000-2004年的54.56%增至2015-2019年的58.19%;变异系数和区位基尼系数分析表明,国家自然科学基金医学领域经费投入省际间差异状况虽有所改善,但仍存在较大差距;分级地图显示,国家自然科学基金医学领域经费投入主要集中在北京、上海、广东、江苏等省份;从时空演变趋势来看,投入“重心”由北京转移至上海,且高水平区域呈现逐渐向东部沿海省份集聚态势。结论:国家自然科学基金医学领域经费投入呈大幅增长态势,省际间差异逐渐缩小,但省域空间分异格局明显,且区域间差异较大并随时间推移呈扩大趋势。因此,相关部门应通过制定措施以优化医学科技创新资源空间布局,促进各地区医学科学创新协调发展。

中国新质生产力水平测度及其对经济高质量发展的影响效应

根据新质生产力的理论内涵,本文从实体性和渗透性两个维度构建新质生产力综合评价指标体系,借助2012—2022年省级面板数据测度了中国新质生产力水平,并进一步探讨了新质生产力对经济高质量发展的影响。研究表明:在时序演变方面,中国新质生产力的总体水平及其构成要素的分项发展水平均呈现稳步上升的趋势;在空间分布方面,中国四大地区的新质生产力发展水平存在差异性,但差距正在不断缩小;在因果关系方面,新质生产力能显著促进经济的高质量发展,在处理内生性问题后结论依然成立。此外,空间杜宾模型估计结果显示,新质生产力对经济高质量发展不仅存在直接促进作用,而且存在显著的空间溢出效应。

长江流域农业绿色发展水平评价与时空差异分析

对长江流域农业绿色发展水平进行评价与影响因素分析,能促进长江流域农业绿色高质量发展。基于2006—2020年长江流域19个省份的面板数据,从绿色生产、绿色生态、经济效益、生活水平四个维度构建了农业绿色发展水平评价指标体系;并通过熵权法对各省份农业绿色发展水平进行测度;最后应用区域差异分析法、空间自相关性分析对区域内与区域间的时空发展差异、关联度进行探讨。结果表明:(1)长江流域农业绿色发展水平整体呈现出稳步上升趋势,干流发展趋势优于支流。(2)长江流域农业绿色发展水平区域差异呈现出波动扩大的变化趋势。(3)长江流域各省份农业绿色发展水平显示出空间聚集效应,其中上海、江苏、浙江是高—高聚集模式,重庆、贵州、广西是低—低聚集模式。因此,要提高长江流域农业绿色发展水平,各省份应制定个性化政策、重视并补齐发展短板、加强区域间辐射效应。

中国县城土地利用效率时空差异及影响因素分析

运用超效率SBM模型、Malmquist指数、Tobit回归模型等分析2006—2020年我国县城土地利用效率的时空差异及其影响因素,结果表明:①研究期内我国县城土地利用效率呈“W”形波动上升态势,空间上呈东部地区>中部地区>西部地区,东部与中部地区的差距不断缩小,西部与东、中部地区的差距有所扩大;②研究期内我国县城土地利用全要素生产率年均增长率为3.4%,县城土地利用效率提高主要得益于技术进步;③县域城镇化水平、县域经济发展水平、县城建设用地规模以及产业结构升级可以促进县城土地利用效率提升,地方财政压力、交通设施水平对县城土地利用效率起抑制作用,各影响因素的作用结果存在区域异质性。今后应以创新城乡用地制度、优化建设用地配置方式和土地供给结构为保障,因地制宜优化产业结构、完善县城基础设施,促进县域经济、城镇化发展,提高县城土地综合效益,进而提升县城土地利用效率。

人类福祉视角下城市生态效率时空差异与障碍诊断——以黑龙江省为例

基于2010-2019年黑龙江省12个地级市的面板数据,从人类福祉视角构建城市生态效率的指标体系,运用考虑非期望产出的超效率SBM模型与Malmquist指数进行分析,揭示黑龙江省12个地级市生态效率时空差异特征及其动态变化驱动力,并利用障碍度模型识别阻碍黑龙江城市生态效率提升的关键因素。结果表明:①黑龙江省12个地级市整体效率水平呈缓慢上升态势,年均增速1.313%;②城市生态效率呈高值连片空间分布特征,逐步形成中西部和东部两条高效率城市带;③纯技术效率、技术进步是促进其全要素生产率的主导驱动因素,两者变化指数平均值分别为1.070、1.035;④黑龙江省城市生态效率的主要障碍因子为全社会固定资产投资、实际地区生产总值和全社会用电量,而人类福祉对生态效率阻碍程度相对较小。据此,从区域协调发展、找准驱动路径、加快城市绿色转型等方面提出提升城市生态效率、推动黑龙江省城市可持续发展的建议。

广东省数字经济发展及时空差异特征分析

数字经济是引领经济高质量发展的新动能。为反映广东省数字经济发展水平,本文通过构建数字经济指标体系,运用熵值法,测算了广东省21个地市数字经济发展指数,反映其十年来数字经济发展变化趋势,并通过可视化处理,分析各区域数字经济发展水平的空间集聚特征。研究发现,广东省各地市数字经济发展差异明显,各区域数字经济发展水平呈现动态波动性。从数字经济发展时空分布情况来看,进入第一梯队与第二梯队的城市长期以来稳定不变,而进入第三、四、五梯队的城市有所调整变化。据此,本文从政府、产业与企业层面提出对策建议。

中国现代化金融生态系统建设及其区域差异研究

2023年10月,我国首次提出建设金融强国的战略目标,而现代化金融生态系统建设是实现该目标的重要条件。利用熵权法、泰尔指数法对八大综合经济区现代化金融生态系统建设水平进行实证研究。研究发现:现代化金融生态系统在2013—2022年之间呈现出较大的波动趋势,整体呈现“东部沿海>北部沿海、南部沿海>长江中游、黄河中游>西南地区>东北地区、西北地区”态势;上海、江苏、浙江、北京、广东排名靠前;东部沿海地区内部的联动效应高,南部沿海地区的联动效应低;八大综合经济区的组间差异对整体差异的贡献度呈上升趋势,区域间发展水平差距在逐渐扩大;东北地区、黄河中游、西南地区、西北地区内部发展水平差距波动大。最后文章提出应加强区域内和区域间现代化金融生态系统的联动效应,促进金融资源的有效配置和利用;因地制宜制定当地政策,推动本地金融科技产业的发展,打造本地金融科技创新生态圈;加强金融风险防范,提高金融市场的透明度和规范性等建议。