规模报酬递增与京津冀都市区经济增长     

郭腾云  董冠鹏  孙威 《地理研究》2011,30(10):1873-1881

借助Verdoorn法则,并将其拓展至区域经济研究框架,以京津冀都市区为研究区域,将其经济增长过程分为1995～2000年、2000～2007年及1995～2007年3个时段,采用Spa-tial Durbin Model和空间贝叶斯异方差回归模型将空间自相关和空间异质性纳入传统Ver-doorn法则的经验估计中,得到...  相似文献   

山地城镇体系规模结构的计量分析及分形特征研究——以滇西南临沧市为例     

张锦  王培茗 《云南地理环境研究》2011,23(6):64-69

以滇西南地区临沧市2003～2008年各山地小城镇的人口规模数据为基础,运用城市地理学中的位序-规模法则、城市首位律及不平衡指数和自组织理论中的分形理论相结合的方法,对临沧市城镇体系规模等级结构进行定量和定性分析,从计量分析和分形研究两个方面对临沧市城镇体系规模等级结构特征进行总结,结果表明,临沧市城镇体系规模等级结构具有分形特征,处于低级平衡状态,发育还不成熟,但有开始走向成熟的趋势。最后根据临沧市城镇体系规模结构的特征提出相应发展建议。  相似文献   

U—TAE算法提取城市热岛信息的空间尺度分析   总被引：1，自引：0，他引：1  

刘宇鹏  杨波  陈崇 《地理科学进展》2011,30(9):1118-1124

U-TAE算法是一种使用不同范围的滑动窗口来提取城市热岛信息并根据稳健估计法设定窗口阈值的算法,该算法根据像元被记为热岛像元的累积总次数是否为0来区别热岛区与非热岛区,根据累积总次数的多少来判断热岛强度的强弱,具有动态阈值的特点和无偏特性。文章以长沙地区为例,对U-TAE算法在6个不同空间尺度上（5×5,11×11,25×25,51×51,101×101,201×201）对城市热岛信息提取的效果从提取范围、提取强度、空间构成以及大面积热岛提取稳定程度4个方面进行了评估。结果认为大小为11×11的窗口在4个方面均取得较好的效果,提取的城市热岛信息更加完整和有效。  相似文献   

京津冀都市圈城镇体系演化时空特征   总被引：4，自引：1，他引：3  

肖磊  黄金川  孙贵艳 《地理科学进展》2011,30(2):215-223

基于1985、1990、2000和2007年的非农业人口,应用位序规模法则、ROXY指数、城市影响力等多种定量方法,系统研究京津冀都市圈城镇体系的规模结构、空间结构的演化.结果表明:京津冀都市圈虽为"双核"结构,但一直处于分散发展趋势,京、津两个巨型城市的非农人口占京津冀都市圈的比重日趋下降;京津轴线为京津冀都市圈最重...  相似文献   

中国陆地海岸线尺度效应研究(英文)   总被引：2，自引：0，他引：2  

苏奋振  高义  周成虎  杨晓梅  费鲜芸 《地理学报(英文版)》2011,21(6):1101-1111

Spatial scale is a fundamental problem in Geography. Scale effect caused by fractal characteristic of coastline becomes a common focus of coastal zone managers and researchers. In this study, based on DEM and remote sensing images, multi-scale continental coastlines of China were extracted and the fractal characteristic was analyzed. The results are shown as follows. (1) The continental coastline of China fits the fractal model, and the fractal dimension is 1.195. (2) The scale effects with fractal dimensions of coastline have significant differences according to uplift and subsidence segments along the continental coastlines of China. (3) The fractal dimension of coastline has significant spatial heterogeneity according to the coastline types. The fractal dimension of sandy coastline located in Luanhe River plain is 1.109. The dimension of muddy coastline located in northern Jiangsu Plain is 1.059, while that of rocky coastline along southeastern Fujian is 1.293. (4) The length of rocky coastline is affected by scale more than that of muddy and sandy coastline. Since coastline is the conjunction of sea, land and air surface, the study of coastline scale effect is one of the scientific bases for the researches on air-sea-land interaction in multi-scales.  相似文献   

大尺度水循环模拟系统不确定性研究进展(英文)   总被引：2，自引：1，他引：1  

宋晓猛  占车生  孔凡哲  夏军 《地理学报(英文版)》2011,21(5):801-819

The regional hydrological system is extremely complex because it is affected not only by physical factors but also by human dimensions.And the hydrological models play a very important role in simulating the complex system.However,there have not been effective methods for the model reliability and uncertainty analysis due to its complexity and difficulty.The uncertainties in hydrological modeling come from four important aspects:uncertainties in input data and parameters,uncertainties in model structure,uncertainties in analysis method and the initial and boundary conditions.This paper systematically reviewed the recent advances in the study of the uncertainty analysis approaches in the large-scale complex hydrological model on the basis of uncertainty sources.Also,the shortcomings and insufficiencies in the uncertainty analysis for complex hydrological models are pointed out.And then a new uncertainty quantification platform PSUADE and its uncertainty quantification methods were introduced,which will be a powerful tool and platform for uncertainty analysis of large-scale complex hydrological models.Finally,some future perspectives on uncertainty quantification are put forward.  相似文献   

面向对象的山地区域多源遥感影像分割尺度选择及评价     

鲁恒  李永树  唐敏 《山地学报》2011,29(6)

随着遥感技术的飞速发展,通过各种传感器获取的影像种类越来越多.传统的面向像元的影像分析技术已难以适应高分辨率影像,面向对象的影像分析技术应运而生.面向对象的影像分析技术所面临的首要问题是影像分割,如何选择合适的影像分割尺度已成为面向对象影像分析技术的关键.为了提高遥感影像分割尺度选择的准确性,通过对影像分析建立了分割质量函数,针对不同分辨率的多源遥感影像进行分割实验,获取了最优分割尺度,最后提出了一种顾及面积和光谱的分割匹配指数对最优分割尺度进行评价,并研究了分割尺度与亮度均值标准差、影像空间分辨率之间的对应关系.研究结果表明,构建的分割质量函数获取的最优分割尺度避免了人工分割带来的主观性,建立的同时顾及面积和光谱因子的分割匹配指数验证了最优分割尺度选择的正确性.  相似文献   

Spatial and temporal trends in information technology outsourcing     

《Applied geography (Sevenoaks, England)》2015

Over the last two decades information technology (IT) outsourcing has grown dramatically, and has emerged as a strategic choice for firms searching for ways to control their costs and maintain a competitive edge. The mechanisms driving its growth are not fully understood though. In this research, we employ an approach that focuses on geographic, temporal, and industrial proximity in a mechanism that identifies the process underlying the diffusion of IT outsourcing across firms within the U.S from 2000 to 2010. We focus on the role that firm location plays in the diffusion process, and use space-time clustering techniques from the epidemiology literature to understand the diffusion process. We identify 38 space-time clusters based on IT outsourcing announcement data and the locations of firm headquarters among U.S.-based firms. When supplemented with additional information, such as type of services outsourced, the metropolitan area of the headquarters, and related industry information; the results offer insights into various types of diffusion processes that have been identified in the literature but have not been documented to date in the empirical manner that we have been able to do.  相似文献   

基于小波的浙江省NDVI与自然—人文因子多尺度空间关联分析   总被引：1，自引：0，他引：1  

徐芝英  胡云锋  甄霖  庄大方 《地理研究》2015,34(3)

对地表植被的空间分布格局及其与自然、人文因子间的关系开展综合的、多尺度的定量分析,这是全球气候变化背景下土地利用与覆被研究中的一项重要内容。以地处亚热带湿润季风区的浙江省为研究区,设置了东西向(样线A)和北南向(样线B)两条样线,并应用小波分析方法对研究区NDVI、高程、坡度和土地利用强度等因子的尺度特征以及这些因子间的多尺度相关关系进行了分析。结果表明:1研究区内,NDVI、高程、坡度及土地利用强度的空间分布格局存在四个尺度域;2上述因子在样线A及样线B上的空间分布分别存在两个主要特征尺度,其中东西向(样线A)上的特征尺度为40 km和80 km,北南向(样线B)上主要的特征尺度为30 km和50 km;3在较大尺度域(8 km以上),土地利用强度是影响NDVI空间分布的最主要因素,而在小尺度域(0~8 km),坡度和高程因子成为影响NDVI分布的主要因子。研究还认为,小波分析方法为识别地理要素空间分布的特征尺度、量测要素间任意尺度、任意位置上的相干关系,提供了方便的工具。  相似文献   

第四系重新定义的有关建议   总被引：1，自引：1，他引：0  

王伟铭  舒军武  陈炜 《地层学杂志》2004,28(4):319-320,325

当新生界"第三系-第四系"的划分方案被"古近系-新近系"(Gradstein等,2004)所取代后,有关第四系的定义问题在国际学术界产生很大的争议.本文汇集部分国际组织和个人对第四系重新定义的有关建议,以期引起我国地层工作者和第四纪学者对此关注.  相似文献