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Structural Characteristics and Influencing Factors of Carbon Emission Spatial Association Network:A Case Study of Yangtze River Delta City Cluster,China 被引量:2
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作者 BI Xi SUN Renjin +2 位作者 HU Dongou SHI Hongling ZHANG Han 《Chinese Geographical Science》 SCIE CSCD 2024年第4期689-705,共17页
City cluster is an effective platform for encouraging regionally coordinated development.Coordinated reduction of carbon emissions within city cluster via the spatial association network between cities can help coordi... City cluster is an effective platform for encouraging regionally coordinated development.Coordinated reduction of carbon emissions within city cluster via the spatial association network between cities can help coordinate the regional carbon emission management,realize sustainable development,and assist China in achieving the carbon peaking and carbon neutrality goals.This paper applies the improved gravity model and social network analysis(SNA)to the study of spatial correlation of carbon emissions in city clusters and analyzes the structural characteristics of the spatial correlation network of carbon emissions in the Yangtze River Delta(YRD)city cluster in China and its influencing factors.The results demonstrate that:1)the spatial association of carbon emissions in the YRD city cluster exhibits a typical and complex multi-threaded network structure.The network association number and density show an upward trend,indicating closer spatial association between cities,but their values remain generally low.Meanwhile,the network hierarchy and network efficiency show a downward trend but remain high.2)The spatial association network of carbon emissions in the YRD city cluster shows an obvious‘core-edge’distribution pattern.The network is centered around Shanghai,Suzhou and Wuxi,all of which play the role of‘bridges’,while cities such as Zhoushan,Ma'anshan,Tongling and other cities characterized by the remote location,single transportation mode or lower economic level are positioned at the edge of the network.3)Geographic proximity,varying levels of economic development,different industrial structures,degrees of urbanization,levels of technological innovation,energy intensities and environmental regulation are important influencing factors on the spatial association of within the YRD city cluster.Finally,policy implications are provided from four aspects:government macro-control and market mechanism guidance,structural characteristics of the‘core-edge’network,reconfiguration and optimization of the spatial layout of the YRD city cluster,and the application of advanced technologies. 展开更多
关键词 carbon emission spatial association network social network analysis(SNA) quadratic assignment procedure(QAP)model Yangtze River Delta city cluster China
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Slope deformation partitioning and monitoring points optimization based on cluster analysis 被引量:4
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作者 LI Yuan-zheng SHEN Jun-hui +3 位作者 ZHANG Wei-xin ZHANG Kai-qiang PENG Zhang-hai HUANG Meng 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2405-2421,共17页
The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine... The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine the number and location of monitoring points according to the actual deformation characteristics of the slope.There are still some defects in the layout of monitoring points.To this end,based on displacement data series and spatial location information of surface displacement monitoring points,by combining displacement series correlation and spatial distance influence factors,a spatial deformation correlation calculation model of slope based on clustering analysis was proposed to calculate the correlation between different monitoring points,based on which the deformation area of the slope was divided.The redundant monitoring points in each partition were eliminated based on the partition's outcome,and the overall optimal arrangement of slope monitoring points was then achieved.This method scientifically addresses the issues of slope deformation zoning and data gathering overlap.It not only eliminates human subjectivity from slope deformation zoning but also increases the efficiency and accuracy of slope monitoring.In order to verify the effectiveness of the method,a sand-mudstone interbedded CounterTilt excavation slope in the Chongqing city of China was used as the research object.Twenty-four monitoring points deployed on this slope were monitored for surface displacement for 13 months.The spatial location of the monitoring points was discussed.The results show that the proposed method of slope deformation zoning and the optimized placement of monitoring points are feasible. 展开更多
关键词 Excavation slope Surface displacement monitoring spatial deformation analysis clustering analysis Slope deformation partitioning Monitoring point optimization
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Spatial Heterogeneity Analysis of PM2.5 Concentration in Central Plains Economic Region
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作者 Kaiguang Zhang Hongling Meng +1 位作者 Mingting Ba Yanmin Sun 《Journal of Geoscience and Environment Protection》 2020年第12期244-254,共11页
The research of the spatial heterogeneity of PM2.5 concentration in an area, is of great significance for understanding its regional spatial distribution structure, exploring the transmission relationship between regi... The research of the spatial heterogeneity of PM2.5 concentration in an area, is of great significance for understanding its regional spatial distribution structure, exploring the transmission relationship between regions, in order to formulate joint prevention and control measures within the entire area. Based on the daily monitoring data of PM2.5 concentration in the Central Plains Economic Region in 2019, this paper utilizes cluster analysis to divide the regional PM2.5 concentration into 5 classes, builds their spatial semi-variogram model, and then utilizes interpolation analysis method to study the regional overall distribution characteristics and transmission law. The results show that the PM2.5 concentration in the Central Plains Economic Region has a medium or higher spatial autocorrelation. The critical value of the overall PM2.5 concentration in the area is 150 μg/m3, as the overall PM2.5 concentration less than the value, the PM2.5 in a region mainly comes from local emissions, as the overall PM2.5 concentration higher than the value, the influence of spatial structure on the distribution of PM2.5 concentration is gradually obvious. PM2.5 has a certain degree of spatial transmission, which mainly includes two routes as Puyang-Xingtai and Puyang-Zhengzhou, and the transmission intensity of the former is greater than the latter. 展开更多
关键词 cluster analysis Semi-Variogram spatial Heterogeneity spatial Structure Central Plains Economic Region
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Spatial quality evaluation for drinking water based on GIS and ant colony clustering algorithm 被引量:4
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作者 侯景伟 米文宝 李陇堂 《Journal of Central South University》 SCIE EI CAS 2014年第3期1051-1057,共7页
To develop a better approach for spatial evaluation of drinking water quality, an intelligent evaluation method integrating a geographical information system(GIS) and an ant colony clustering algorithm(ACCA) was used.... To develop a better approach for spatial evaluation of drinking water quality, an intelligent evaluation method integrating a geographical information system(GIS) and an ant colony clustering algorithm(ACCA) was used. Drinking water samples from 29 wells in Zhenping County, China, were collected and analyzed. 35 parameters on water quality were selected, such as chloride concentration, sulphate concentration, total hardness, nitrate concentration, fluoride concentration, turbidity, pH, chromium concentration, COD, bacterium amount, total coliforms and color. The best spatial interpolation methods for the 35 parameters were found and selected from all types of interpolation methods in GIS environment according to the minimum cross-validation errors. The ACCA was improved through three strategies, namely mixed distance function, average similitude degree and probability conversion functions. Then, the ACCA was carried out to obtain different water quality grades in the GIS environment. In the end, the result from the ACCA was compared with those from the competitive Hopfield neural network(CHNN) to validate the feasibility and effectiveness of the ACCA according to three evaluation indexes, which are stochastic sampling method, pixel amount and convergence speed. It is shown that the spatial water quality grades obtained from the ACCA were more effective, accurate and intelligent than those obtained from the CHNN. 展开更多
关键词 geographical information system (GIS) ant colony clustering algorithm (ACCA) quality evaluation drinking water spatial analysis
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Spatio-temporal analysis of female breast cancer incidence in Shenzhen,2007-2012 被引量:6
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作者 Hai-Bin Zhou Sheng-Yuan Liu +4 位作者 Lin Lei Zhong-Wei Chen Ji Peng Ying-Zhou Yang Xiao-Li Liu 《Chinese Journal of Cancer》 SCIE CAS CSCD 2015年第5期198-204,共7页
Introduction:Breast cancer is a leading tumor with a high mortality in women.This study examined the spatio-temporal distribution of the incidence of female breast cancer in Shenzhen between 2007 and 2012.Methods:The ... Introduction:Breast cancer is a leading tumor with a high mortality in women.This study examined the spatio-temporal distribution of the incidence of female breast cancer in Shenzhen between 2007 and 2012.Methods:The data on breast cancer incidence were obtained from the Shenzhen Cancer Registry System.To describe the temporal trend,the average annual percentage change(AAPC) was analyzed using a pinpoint regression model.Spatial autocorrelation and a retrospective spatio-temporal scan approach were used to detect the spatio-temporal cluster distribution of breast cancer cases.Results:Breast cancer ranked first among different types of cancer in women in Shenzhen between 2007 and 2012 with a crude incidence of 20.0/100,000 population.The age-standardized rate according to the world standard population was 21.1/100,000 in 2012,with an AAPC of 11.3%.The spatial autocorrelation analysis showed a spatial correlation characterized by the presence of a hotspot in south-central Shenzhen,which included the eastern part of Luohu District(Donghu and Liantang Streets) and Yantian District(Shatoujiao,Haishan,and Yantian Streets).Five spatio-temporal cluster areas were detected between 2010 and 2012,one of which was a Class 1 cluster located in southwestern Shenzhen in 2010,which included Yuehai,Nantou,Shahe,Shekou,and Nanshan Streets in Nanshan District with an incidence of 54.1/100,000 and a relative risk of 2.41;the other four were Class 2 clusters located in Yantian,Luohu,Futian,and Longhua Districts with a relative risk ranging from 1.70 to 3.25.Conclusions:This study revealed the spatio-temporal cluster pattern for the incidence of female breast cancer in Shenzhen,which will be useful for a better allocation of health resources in Shenzhen. 展开更多
关键词 深圳地区 时空分析 乳腺癌 发病率 女性 空间自相关分析 时空分布 空间相关性
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Multiscale 3D spatial analysis of the tumor microenvironment using whole-tissue digital histopathology
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作者 Daniel Shafiee Kermany Ju Young Ahn +14 位作者 Matthew Vasquez Weijie Zhang Lin Wang Kai Liu Zhan Xu Min Soon Cho Wendolyn Carlos-Alcalde Hani Lee Raksha Raghunathan Jianting Sheng Xiaoxin Hao Hong Zhao Vahid Afshar-Kharghan Xiang Hong-Fei Zhang Stephen Tin Chi Wong 《Cancer Communications》 2025年第3期386-390,共5页
Spatial statistics are crucial for analyzing clustering patterns in various spaces,such as the distribution of trees in a forest or stars in the sky.Advances in spatial biology,such as single-cell spatial transcriptom... Spatial statistics are crucial for analyzing clustering patterns in various spaces,such as the distribution of trees in a forest or stars in the sky.Advances in spatial biology,such as single-cell spatial transcriptomics,enable researchers to map gene expression patterns within tissues,offering unprecedented insights into cellular functions and disease pathology.Common methods for deriving spatial relationships include density-based methods(quadrat analysis,kernel density estimators)and distance-based methods(nearest-neighbor distance[NND],Ripley’s K function).While density-based methods are effective for visualization,they struggle with quantification due to sensitivity to parameters and complex significance tests.In contrast,distance-based methods offer robust frameworks for hypothesis testing,quantifying spatial clustering or dispersion,and facilitating comparisons with models such as uniform random distributions or Poisson processes[1,2]. 展开更多
关键词 spatial statistics map gene expression patterns analyzing clustering patterns d spatial analysis whole tissue digital histopathology spatial biologysuch multiscale tumor microenvironment
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Spatio-temporal analysis of the incidence of colorectal cancer in Guangzhou,2010-2014
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作者 Ke Li Guo-Zhen Lin +5 位作者 Yan Li Hang Dong Huan Xu Shao-Fang Song Ying-Ru Liang Hua-Zhang Liu 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第10期516-523,共8页
Introduction: Colorectal cancer(CRC) is a common type of neoplasm. This study examined the spatio?temporal distribution of the CRC incidence in Guangzhou during 2010–2014.Methods: Colorectal cancer incidence data wer... Introduction: Colorectal cancer(CRC) is a common type of neoplasm. This study examined the spatio?temporal distribution of the CRC incidence in Guangzhou during 2010–2014.Methods: Colorectal cancer incidence data were obtained from the Guangzhou Cancer Registry System. Spatial autocorrelation analysis and a retrospective spatio?temporal scan were used to assess the spatio?temporal cluster distribution of CRC cases.Results: A total of 14,618 CRC cases were registered in Guangzhou during 2010–2014, with a crude incidence of 35.56/100,000 and an age?standardized rate of incidence by the world standard population(ASRIW) of 23.58/100,000. The crude incidence increased by 19.70% from 2010(32.88/100,000) to 2014(39.36/100,000) with an average annual percentage change(AAPC) of 4.33%. The AAPC of ASRIW was not statistically significant. The spatial autocorrelation analysis revealed a CRC incidence hot spot in central urban areas in Guangzhou City, which included 25 streets in southwestern Baiyun District, northwestern Haizhu District, and the border region between Liwan and Yuexiu Dis?tricts. Three high? and five low?incidence clusters were identified according to spatio?temporal scan of CRC incidence clusters. The high?incidence clusters were located in central urban areas including the border regions between Bai?yun, Haizhu, Liwan, and Yuexiu Districts.Conclusions: This study revealed the spatio?temporal cluster pattern of the incidence of CRC in Guangzhou. This information can inform allocation of health resources for CRC screening. 展开更多
关键词 Colorectal cancer spatial analysis spatial autocorrelation Spatio-temporal clustering
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Spatial Distribution Pattern and Influencing Factors of Bed-and-breakfasts(B&Bs)from the Perspective of Urban-rural Differences:A Case Study of Jiaodong Peninsula,China 被引量:1
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作者 WANG Xinyue MA Qian 《Chinese Geographical Science》 SCIE CSCD 2024年第4期752-763,共12页
There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial carrier.Accurately identifying the differences in spatial characteri... There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial carrier.Accurately identifying the differences in spatial characteristics and influencing factors of each type,is essential for creating urban and rural B&B agglomeration areas.This study used density-based spatial clustering of applications with noise(DBSCAN)and the multi-scale geographically weighted regression(MGWR)model to explore similarities and differences in the spatial distribution patterns and influencing factors for urban and rural B&Bs on the Jiaodong Peninsula of China from 2010 to 2022.The results showed that:1)both urban and rural B&Bs in Jiaodong Peninsula went through three stages:a slow start from 2010 to 2015,rapid development from 2015 to 2019,and hindered development from 2019 to 2022.However,urban B&Bs demonstrated a higher development speed and agglomeration intensity,leading to an increasingly evident trend of uneven development between the two sectors.2)The clustering scale of both urban and rural B&Bs continued to expand in terms of quantity and volume.Urban B&B clusters characterized by a limited number,but a higher likelihood of transitioning from low-level to high-level clusters.While the number of rural B&B clusters steadily increased over time,their clustering scale was comparatively lower than that of urban B&Bs,and they lacked the presence of high-level clustering.3)In terms of development direction,urban B&B clusters exhibited a relatively stable pattern and evolved into high-level clustering centers within the main urban areas.Conversely,rural B&Bs exhibited a more pronounced spatial diffusion effect,with clusters showing a trend of multi-center development along the coastline.4)Transport emerged as a common influencing factor for both urban and rural B&Bs,with the density of road network having the strongest explanatory power for their spatial distribution.In terms of differences,population agglomeration had a positive impact on the distribution of urban B&Bs and a negative effect on the distribution of rural B&Bs.Rural B&Bs clustering was more influenced by tourism resources compared with urban B&Bs,but increasing tourist stay duration remains an urgent issue to be addressed.The findings of this study could provide a more precise basis for government planning and management of urban and rural B&B agglomeration areas. 展开更多
关键词 urban-rural bed-and-breakfasts(B&Bs) spatiotemporal evolution density-based spatial clustering of applications with noise(DBSCAN)model multi-scale geographically weighted regression(MGWR) Jiaodong Peninsula China
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Gonorrhea cluster detection in Manitoba,Canada:Spatial,temporal,and spatio-temporal analysis
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作者 Amin Abed Mahmoud Torabi Zeinab Mashreghi 《Infectious Disease Modelling》 CSCD 2024年第4期1045-1056,共12页
In Canada,Gonorrhea infection ranks as the second most prevalent sexually transmitted infection.In 2018,Manitoba reported an incidence rate three times greater than the national average.This study aims to investigate ... In Canada,Gonorrhea infection ranks as the second most prevalent sexually transmitted infection.In 2018,Manitoba reported an incidence rate three times greater than the national average.This study aims to investigate the spatial,temporal,and spatio-temporal patterns of Gonorrhea infection in Manitoba,using individual-level laboratory-confirmed administrative data provided by Manitoba Health from 2000 to 2016.Age and sex patterns indicate that females are affected by infections at younger ages compared to males.Moreover,there is an increase in repeated infections in 2016,accounting for 16%of the total infections.Spatial analysis at the 96 Manitoba regional health authority districts highlights significant positive spatial autocorrelation,demonstrating a clustered distribution of the infection.Northern districts of Manitoba and central Winnipeg were identified as significant clusters.Temporal analysis shows seasonal patterns,with higher infections in late summer and fall.Additionally,spatio-temporal analysis reveals clusters during high-risk periods,with the most likely cluster in the northern districts of Manitoba from January 2006 to June 2014,and a secondary cluster in central Winnipeg from June 2004 to November 2012.This study identifies that Gonorrhea infection transmission in Manitoba has temporal,spatial,and spatio-temporal variations.The findings provide vital insights for public health and Manitoba Health by revealing high-risk clusters and emphasizing the need for focused and localized prevention,control measures,and resource allocation. 展开更多
关键词 cluster detection GONORRHEA Infectious disease spatial analysis Spatio-temporal analysis
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2014—2023年济宁市布鲁氏菌病流行病学时空及病原学特征分析
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作者 孙喜红 甄华 +7 位作者 童彦菊 于颖慧 岳营 姜静静 巩鑫 刘伟 姜文国 梁玉民 《中国人兽共患病学报》 北大核心 2025年第9期967-974,共8页
目的了解2014—2023年济宁市布鲁氏菌病(布病)流行病学特征,为进一步制定该地布病防控策略和措施提供参考依据。方法采用描述性流行病学方法,分析2014—2023年济宁市布病流行病学特征;以乡镇为基本单元,通过空间自相关分析研究济宁市布... 目的了解2014—2023年济宁市布鲁氏菌病(布病)流行病学特征,为进一步制定该地布病防控策略和措施提供参考依据。方法采用描述性流行病学方法,分析2014—2023年济宁市布病流行病学特征;以乡镇为基本单元,通过空间自相关分析研究济宁市布病发病的空间区域相关性及局部区域的聚类模式。结果2014—2023年济宁市共报告布病病例3520例,年均发病率为4.23/10万,总体呈波动态势;3-8月为报告病例高峰期;男女发病数性别比为2.71∶1;40~59岁年龄组报告病例数最多(50.39%)。济宁市布病发病特征呈非均衡分布的空间格局;布病发病呈现空间聚类分布(Moran's I值>0,P<0.05);热点地区主要分布在泗水县、曲阜市和邹城市的多个乡镇(街道)。时空扫描共探测到Ⅰ类聚集区1个(泗水县和曲阜市辖区内)、Ⅱ类聚集区1个(梁山县)。病原学AMOS-PCR分型分析显示,济宁市2022—2024年采集64株布鲁氏菌均为羊种菌株,以羊种生物3型为主(70.31%)。结论2014—2023年济宁市布病发病呈高位但下降态势,布病发病存在空间聚集性,主要为羊种菌株,济宁市布病主要集中在东北部地区,应加强聚集性地区布病从业人员的宣传教育及病例监测,提高从业人员防护水平,做到早发现、早治疗。 展开更多
关键词 布鲁氏菌病 流行病学特征 时空聚集性 菌种鉴定 空间自相关 热点分析
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金山区托幼机构和学校手足口病聚集性疫情时空聚集性分析
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作者 王唐 董兆鹏 +3 位作者 李淑华 莫平华 赵艺明 宋灿磊 《医学动物防制》 2025年第8期755-759,共5页
目的了解2016—2021年金山区托幼机构和学校手足口病(hand-foot-mouth disease,HFMD)聚集性疫情时空聚集特征,为辖区HFMD疫情防控提供科学依据。方法收集2016—2021年金山区托幼机构和学校HFMD聚集性疫情调查资料,采用ArcGIS 10.4.1软... 目的了解2016—2021年金山区托幼机构和学校手足口病(hand-foot-mouth disease,HFMD)聚集性疫情时空聚集特征,为辖区HFMD疫情防控提供科学依据。方法收集2016—2021年金山区托幼机构和学校HFMD聚集性疫情调查资料,采用ArcGIS 10.4.1软件进行空间自相关分析,采用SaTScan V9.6软件进行时空扫描,分析金山区托幼机构和学校HFMD聚集性疫情的时空聚集特征。结果2016—2021年金山区托幼机构和学校共报告HFMD聚集性疫情338起。全局空间自相关分析显示,通过改变K最邻近法(K-nearest neighbors,KNN)的K值,2019年HFMD聚集性疫情起数均存在空间聚集性(Moran′s I=0.07~0.21,均P<0.05),其余年份HFMD聚集性疫情起数显示不同的空间自相关分析结果。聚类和异常值分析显示有26个高值(high-high,HH)聚类点,9个高低(high-low,HL)聚类点,3个低高(low-high,LH)聚类点,无低值(low-low,LL)聚类点。时空扫描结果共显示6个主聚集区,涉及8个街镇(高新区)的54家单位,主要位于金山区东南部、东北部和枫泾镇;主聚集区聚集时间分布在5—6月和11—12月。结论2016—2021年金山区托幼机构和学校HFMD聚集性疫情呈聚集分布,HFMD疫情高发单位主要分布在朱泾镇、山阳镇、亭林镇和枫泾镇,仍是今后金山区HFMD疫情防控的重点。 展开更多
关键词 手足口病 聚集性疫情 空间自相关分析 时空扫描分析
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区域物流空间网络结构演变与作用机制——以湖南省为例
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作者 李利华 曹梦 +3 位作者 谭乐怡 张镜夕 邢珂珂 宋琨 《经济地理》 北大核心 2025年第8期139-151,共13页
区域物流先导地区高质量发展,其空间网络引领区域空间重构。文章以经济发展与地理关系为基准,划定湖南省99个县级行政单元;在此基础上,挖掘2010—2022年面板数据与地理信息,评估区域物流综合能力与联系强度,映射其空间网络格局;最后运用... 区域物流先导地区高质量发展,其空间网络引领区域空间重构。文章以经济发展与地理关系为基准,划定湖南省99个县级行政单元;在此基础上,挖掘2010—2022年面板数据与地理信息,评估区域物流综合能力与联系强度,映射其空间网络格局;最后运用SNA、GIS与QAP等探究其区域物流网络演变特征与作用机制。结果表明:(1)湖南省区域物流综合能力时空分异和空间网络层级显著,聚集与分化特征明显。物流联系强度由中心向外围圈层式减弱,呈现以长沙为核心向外“环形递减”格局;物流网络多级分化,呈现“一核多中心,弱链接主导”形态;长株潭城市群物流聚集态势强,中东部与西部是全省物流热点区域。(2)湖南省区域物流空间网络结构密集化、成熟化、均衡化。区域物流聚集性强,网络扩张,由“一核多点”局部聚类向“核心—半边缘—边缘”三层半圈结构演变;网络核心溢出与区位链接邻近明显,“马太效应”减弱,形成长沙带动下的“一极多点”态势;网络联系外强内弱,中心单元主导,有虹吸与溢出效应,孤立单元量少,作用于边缘圈层,整体网络可达性与延伸性好;子群空间聚集深化,群向链接效率向好,最大引力线结构稳定,区域物流资源控制力强。(3)地域邻接是湖南省区域物流空间网络结构演变的主驱动力,经济发展支撑区域物流的资源输出与联系密化,基础条件拉动网络的可达与延伸,物流价值表征区域物流价值能力与规模效益,各差异因素协同交互作用。 展开更多
关键词 区域物流 物流联系强度 空间网络 结构演变 空间集聚 网络密度 社会网络分析
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生态安全约束下环鄱阳湖城市群产业投资空间关联网络与驱动因素研究
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作者 刘耀彬 王梓畅 +1 位作者 骆康 胡伟辉 《长江流域资源与环境》 北大核心 2025年第8期1677-1692,共16页
流空间背景下企业异地投资为城市网络发展注入强大动力,生态安全影响着产业投资网络的形成和结构。环鄱阳湖城市群是人地矛盾敏感地带,自然生态底色具有湖域独特性。以环鄱阳湖城市群为研究区域,运用生态安全约束下城市群流空间的研究框... 流空间背景下企业异地投资为城市网络发展注入强大动力,生态安全影响着产业投资网络的形成和结构。环鄱阳湖城市群是人地矛盾敏感地带,自然生态底色具有湖域独特性。以环鄱阳湖城市群为研究区域,运用生态安全约束下城市群流空间的研究框架,采用修正引力模型刻画其产业投资流关联强度,运用社会网络分析法探讨其生态安全约束下产业投资的空间关联网络特征及驱动因素。研究发现:(1)生态安全约束下环鄱阳湖城市群产业投资空间网络具有明显的“中心—外围”特征,且产业投资流的空间联系在不断加强,网络结构愈发稳定;(2)少数经济较发达地区长期占据网络的中心位置,同时扮演高效的中介角色,网络外围地区存在发展路径突破现象;(3)生态安全约束下环鄱阳湖城市群产业投资空间关联网络的板块特征存在较强的空间依赖性,同一板块的城市在地理位置上呈现抱团取暖特征;(4)对外开放水平、政府调控、人口城镇化水平和土地城镇化水平的相近性对生态安全约束下环鄱阳湖城市群产业投资的空间网络具有显著正向影响。 展开更多
关键词 产业投资流 空间关联网络 生态安全约束 驱动因素 社会网络分析 环鄱阳湖城市群
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极端暴雨过程对海河流域暴雨分布特征的影响 被引量:1
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作者 程宸 房小怡 +5 位作者 张硕 于瀛 杨舒楠 李雁 刘家宏 梅超 《大气科学学报》 北大核心 2025年第2期289-299,共11页
为研究极端暴雨过程对海河流域暴雨空间分布特征的影响,利用流域内252个国家气象站1961—2023年日降雨量数据划分了暴雨过程,计算总暴雨日数(I_(day))、累积降雨量(I_(pre))、平均日降雨量(I_(24pre))和最长持续天数(I_(dur))4个暴雨特... 为研究极端暴雨过程对海河流域暴雨空间分布特征的影响,利用流域内252个国家气象站1961—2023年日降雨量数据划分了暴雨过程,计算总暴雨日数(I_(day))、累积降雨量(I_(pre))、平均日降雨量(I_(24pre))和最长持续天数(I_(dur))4个暴雨特征变量,分析了流域历史时间段和“23.7”“63.8”两次极端暴雨过程的空间分布特征,进而采用K均值聚类分析了两次极端暴雨过程对流域暴雨空间分布特征的影响,定量评估了影响贡献率。结果显示,海河流域在太行山前西南至东北一线的气象站历史时间段I_(day)相对少,但I_(pre)更多,暴雨过程极端性更强。“23.7”暴雨过程覆盖范围比“63.8”过程大,超过50%的气象站I_(day)≥3 d,I_(dur)最长为6 d,单站最大I_(pre)和I_(24pre)分别为1009.7 mm和452.7 mm·d^(-1)。若无两次极端暴雨过程,海河流域暴雨分布特征将更均质化,由“山区-山前平原-平原”分布变为“山区-山前及平原”分布。单次极端暴雨过程对流域暴雨特征变量的贡献率可超过10%。 展开更多
关键词 极端暴雨过程 海河流域 空间分布特征 聚类分析 贡献率
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2018—2020年安徽省食管癌死亡空间流行病学分析
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作者 张绍华 邢秀雅 +1 位作者 徐庆华 苏虹 《中华疾病控制杂志》 北大核心 2025年第4期431-436,共6页
目的通过空间流行病学分析,探索安徽省食管癌死亡的空间分布特征,确定食管癌死亡重点区域。方法收集安徽省2018—2020年死因监测资料,采用Kriging空间插值方法绘制食管癌死亡地理分布图,采用空间自相关分析安徽省食管癌死亡的空间分布规... 目的通过空间流行病学分析,探索安徽省食管癌死亡的空间分布特征,确定食管癌死亡重点区域。方法收集安徽省2018—2020年死因监测资料,采用Kriging空间插值方法绘制食管癌死亡地理分布图,采用空间自相关分析安徽省食管癌死亡的空间分布规律,采用空间扫描统计分析探索食管癌的死亡聚集区。结果2018—2020年安徽省食管癌年均粗死亡率为14.92/10万,年均标化死亡率为10.39/10万。历年男性食管癌死亡率均高于女性(均P<0.05)。空间自相关分析显示,安徽省食管癌死亡的空间分布具有聚集性(莫兰指数=0.54,Z=8.84,P<0.001),聚集区主要位于大别山东侧的庐江县、枞阳县、桐城市,男、女性的主要聚集区域一致。时空扫描分析显示,安徽省食管癌存在3个主要聚集区(均P<0.05)。结论安徽省食管癌死亡率在地区和人群中存在差异,且存在高死亡聚集区,主要分布在大别山东侧。 展开更多
关键词 空间流行病学 食管癌 聚集性 空间自相关 时空扫描分析
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2014-2023年云南省迪庆藏族自治州水痘流行特征及时空聚集分析
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作者 王仕莲 张籍丽 +6 位作者 李向兰 彭晓帝 谭敏 董雪梅 潘丽 朱俊洁 邓淑珍 《疾病监测》 北大核心 2025年第9期1129-1136,共8页
目的分析2014-2023年云南省迪庆藏族自治州(迪庆州)水痘疫情流行特征,为水痘疫情防控提供理论依据。方法采用描述性流行病学方法、空间自相关和时空聚类分析方法,分析迪庆州水痘流行病学特征和时空分布特征。结果2014-2023年迪庆州水痘... 目的分析2014-2023年云南省迪庆藏族自治州(迪庆州)水痘疫情流行特征,为水痘疫情防控提供理论依据。方法采用描述性流行病学方法、空间自相关和时空聚类分析方法,分析迪庆州水痘流行病学特征和时空分布特征。结果2014-2023年迪庆州水痘年均报告发病率105.54/10万,总体呈波动下降趋势(趋势χ^(2)=78.167,P<0.001)。水痘发病高峰日为5月25日,流行高峰期为10月1日至次年1月15日,女性发病率(107.32/10万)高于男性(103.95/10万)。年龄方面以10~14岁年龄组占比最多(24.56%),职业方面以学生占比最高(56.29%),其次为农民(26.23%)。时空扫描分析发现2个聚集区,迪庆州北部德钦县和香格里拉市的云岭乡、升平镇、羊拉乡等10个乡镇组成的区域构成一类聚集区,聚集时间为2016-2018年。迪庆州水痘发病率存在空间正相关性,局部自相关分析提示高–高聚集区主要在德钦县佛山乡、云岭乡。标准差椭圆及中心分析显示迪庆州水痘报告发病率的空间格局分布呈现西北至东南格局。2014—2023年迪庆州水痘发病重心从地区中心逐渐向西北方向偏移,水痘发病率椭圆面积总体呈现缩小的趋势。结论2014-2023年迪庆州水痘发病率总体呈下降趋势,主要集中在迪庆州西北德钦县,有必要对水痘发病聚集区进行进一步调查,以制定针对性的防控措施。 展开更多
关键词 水痘 流行特征 三间分布 空间自相关 时空聚集性分析
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2008-2023年云南省甲型肝炎流行病学特征及时空聚集性分析
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作者 李宁 贾豫晨 +3 位作者 刘榕 邬志薇 王紫鉴 何继波 《疾病监测》 北大核心 2025年第2期189-195,共7页
目的分析2008—2023年云南省甲型肝炎(甲肝)流行病学特征和时空聚集性分布特征,为甲肝防控提供理论依据。方法描述甲肝病例的三间分布特征,发病率和年龄趋势使用线性回归趋势检验。使用R4.3.3软件进行全局空间自相关分析和时空扫描分析... 目的分析2008—2023年云南省甲型肝炎(甲肝)流行病学特征和时空聚集性分布特征,为甲肝防控提供理论依据。方法描述甲肝病例的三间分布特征,发病率和年龄趋势使用线性回归趋势检验。使用R4.3.3软件进行全局空间自相关分析和时空扫描分析,采用ArcGIS10.8.2软件进行局部空间自相关分析。结果2008—2023年云南省累计报告甲肝病例27176例,年均报告病例1699例,年均报告发病率为3.62/10万,呈下降趋势(系数b=-0.45,P<0.001)。年龄中位数为28岁,呈上升趋势(决定系数R^(2)=0.89,P<0.01)。2008—2023年,0~、10~、20~和30~岁年龄组人群报告发病率均呈下降趋势(P<0.01)。全局空间自相关分析结果显示,除2011年,2008—2023年均存在全局空间相关性(P<0.05)。局部空间自相关和时空扫描分析结果显示,甲肝高发地区集中在云南省东南部和南部地区,即由丘北县向西南延伸至孟连傣族拉祜族佤族自治县一带,此片区域既是高-高聚集区域,又是一级聚集区(20个县、区)。从2017年开始,普洱市大部分县(区)均为高风险地区。从2020年开始,曲靖市部分县(区)连续多年成为高风险地区。此外,宁蒗彝族自治县作为次级聚集区,实际观测病例数为535例,预期病例数为135例,是聚集性相对危险度(ARR)最高的地区,表明该县具有较高的聚集性发病风险。结论2008—2023年云南省甲肝发病率呈下降趋势,年龄发病高峰后移。高发职业人群由原来的学生和散居儿童转变为农民、离退人员和家务及待业人员。在空间聚集性方面,重点关注由丘北县向西南延伸至孟连傣族拉祜族佤族自治县范围内的高风险聚集县(区),以及已经再次成为高发地区的普洱市部分县(区)和可能成为持续高发地区的曲靖市部分县(区),探索位于云南省西北部的宁蒗彝族自治县ARR值异常升高的原因,为采取针对性防控措施提供依据。 展开更多
关键词 甲型肝炎 空间聚集性分析 不规则时空扫描 流行病学特征
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基于GIS技术和聚类分析的汾河上游草地土壤养分空间特征分析 被引量:1
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作者 李家新 景亚泓 +4 位作者 张俊 净思璞 杨宇星 范博阳 路文杰 《草业学报》 北大核心 2025年第3期17-28,共12页
土壤环境的保护和治理在促进草地健康可持续发展中发挥着关键作用。本研究利用地理信息系统技术,对汾河上游81个草原点的土壤养分状况进行了调查。以土壤化学性质为主要标准的聚类分析将81个地点的表层土壤分为3类。本研究评估了0~10 cm... 土壤环境的保护和治理在促进草地健康可持续发展中发挥着关键作用。本研究利用地理信息系统技术,对汾河上游81个草原点的土壤养分状况进行了调查。以土壤化学性质为主要标准的聚类分析将81个地点的表层土壤分为3类。本研究评估了0~10 cm、10~20 cm和20~30 cm这3个深度的土壤养分空间特征。研究发现,研究区草地土壤健康水平较差,自然含水率较低,全磷及碱解氮含量相对匮乏,土壤pH属弱碱性。各类养分相关指标的空间分布特征存在显著差异。不同指标在不同土层中的最佳拟合模型不同,多数指标的空间自相关性较弱,土壤养分空间变异主要受结构因素和随机因素共同影响;各指标在水平方向上存在明显的空间变异规律。土壤养分浓度高的地点周围也有土壤养分含量高的地点,即高-高集聚区,主要分布在汾河源头地区。土壤养分浓度低的地点也被土壤养分低的地点包围,即低-低集聚区,主要分布在汾河流域东部。低-高集聚区域较为分散,高-低集聚区较少,主要分布在汾河上游南部;在垂直方向上,土壤养分含量具有随着土层的加深而逐渐减少的趋势。各指标的集聚特征无明显的变化规律。研究结果可为退化草地修复提供科学合理的指导意见。 展开更多
关键词 汾河上游 土壤健康 聚类分析 地统计学 空间自相关
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Spatiotemporal distribution of GNSS-derived PWV in Australia from 2010 to 2019
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作者 Pan Zhao Fuyang Ke +1 位作者 Haopeng Wu Min Wei 《Geodesy and Geodynamics》 2025年第4期454-464,共11页
The weather in Australia is significantly influenced by water vapor evaporated fromwarm ocean surfaces,which is closely associated with various extreme weather events in the region,such as floods,droughts,and bushfire... The weather in Australia is significantly influenced by water vapor evaporated fromwarm ocean surfaces,which is closely associated with various extreme weather events in the region,such as floods,droughts,and bushfires.This study utilizes Precipitable Water Vapor(PWV)data from 15 Global Navigation Satellite System(GNSS)stations spanning 2010 to 2019 to investigate the spatiotemporal distribution of atmospheric water vapor across Australia,aiming to improve the accuracy of forecasting hazardous weather events.The results indicate distinct regional features in the spatial distribution of PWV.PWV gradually decreases from coastal areas toward inland regions and increases from south to north.Temporally,the overall trend of PWV remains consistent.From an annual trend perspective,most areas exhibit a decline in PWV content,with the exception of the southwestern coastal region,which shows an increasing trend.Furthermore,the study explores the correlations between PWV content and elevation,latitude,and longitude.Among these,latitude demonstrates the strongest correlation with PWV,with a correlation coefficient as high as 0.88,highlighting the significant impact of latitude on water vapor distribution. 展开更多
关键词 AUSTRALIA GNSS-derived PWV spatial distribution characteristics multi-scale analysis Climate variability
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