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1.
成渝城市群正逐步成为我国西部经济发展的增长极,探索其城市化时空格局对区域协调发展具有指引作用。基于2000—2018年整合夜光遥感数据提取城市群多期建成区空间范围,运用夜光规模统计、标准椭圆、位序—规模法则以及空间自相关等指标、模型定量分析了成渝区域城市化时空过程。结果表明:(1)灯光与统计数据配合下的建成区提取多年平均误差为1.27%,重庆、成都和绵阳市提取验证效果好;(2)19年间成渝各城市夜光规模显著增长,整体累计增长5.6倍,2010年后成渝城市群灯光规模扩张速度显著;(3)区域内各城市的位序—规模(rank-size)由高位序城市集中发展转向区域协调均衡发展,中小城市均有不同程度的扩张;(4)城市群规模重心位于四川资阳市安岳县,重心移动整体上以东南方向为主,空间格局整体呈现以“成都—重庆”为轴线沿西北向东南演变,空间范围逐渐扩张,说明以重庆为主的东南都市圈的社会经济形势更显著,对城市群发展更具影响力;(5)成渝城市群扩展的空间集聚程度逐渐加强,冷热点格局整体呈现冷点区占比大,热点区占比低的特征,热点区主要出现在位于成都与重庆主城区及其周边城镇。研究揭示了成渝城市群均衡发展的特...  相似文献   

2.
针对当前处于大发展变革阶段的新兴城市群时空变化及驱动因素不明的问题,文章基于2012—2017年夜间灯光影像数据,利用数值统计、标准差椭圆和线性回归等分析方法,结合高分遥感数据和其他辅助数据,研究了呼包鄂城市群夜间灯光在地理空间上的规模分布和变化,分析了夜间灯光的灯光变化与经济发展的关系,并进一步探究了城市群夜间灯光发展的扩张强度、方向以及主要驱动因素。研究结果表明:过去6年间,呼包鄂城市群夜间灯光强度呈现“V”型曲线,与其GDP的发展趋势是一致的;通过椭圆重心分析,显示整个城市群的夜间灯光重心向位于西南方向的鄂尔多斯市移动,鄂尔多斯市对整个城市群的经济发展有较强的拉动作用;利用夜间灯光驱动因子分析,并结合高分遥感光学影像以及灯光变化的区域,发现呼包鄂城市群的发展受能源因素的影响最大,是目前主导城市群发展的关键因素。  相似文献   

3.
长株潭城市群交通网络结构洞分析   总被引:1,自引:0,他引:1  
为了深入研究城市群交通网络结构特性,根据长株潭城市群交通网络构建其道路对偶网络,建立网络结构洞算法,运用VC++6.0连接Matlab7.0计算长株潭城市群交通网络的有效规模、效率、约束度、等级度等结构洞理论指标值,对网络使用n-派系算法计算长株潭城市群交通网1派系结构分布,长株潭城市群交通网络1-派系中包括五条道路以上的不存在,包括五条道路极少,占0.24%,包括四条道路较少,占13%。可以得出以下结论:按照等级度指标可将长株潭城市群交通网道路划分为核心、中间、边缘三类;长株潭城市群交通网络不存在着结构自治,在结构上不存在无效道路。  相似文献   

4.
加强城市动态扩张与环境质量变化监测对促进长三角城市群高质量一体化协同发展具有重要意义。基于DMSP/OLS夜间灯光数据、多源环境遥感数据等,运用趋势线分析、综合评价指数(Comprehensive Evaluation Index,CEI)构建等方法,对长三角城市群2001~2013年的城市扩张模式、扩张区内环境质量变化特征及二者的协调性情况进行分析。结果表明:①46.24%的城市显著扩张,上海—苏锡常城市化水平和一体化程度最高,其次为环杭州湾城市群和沿江发展带,此外未形成多区域规模化的城市高速扩张模式,经济总量、对外开放程度和用电水平是长三角城市高速扩张的主要驱动因素;②46.35%的显著扩张区环境逐步恶化,集中在江苏省和安徽省,环境恶化型集聚在合肥主城区周围,浙江省城市环境最优,上海市基本未变,多数城市环境变化主要由PM2.5增长所致;③城市扩张与环境变化叠加结果可反映区域城市发展与生态环境建设的协调程度。上海市嘉定区、浦东新区和崇明岛,苏锡常及沿江地区协调性较弱,浙江省城市的“渐变”分布模式体现其高协调性,合肥市城区表现为环境质量远落后于城市化进程的双系统非协调发展状态。谷歌影像定位结果表明结合DMSP/OLS与CEI可有效检测出区域内由人类活动所产生的环境破坏型地表覆盖类型变化情况。该研究成果可揭示区域可持续发展状况,对长三角双系统动态发展协调性的空间转移研究具有指示作用。  相似文献   

5.
For the most rapidly growing economic entity in the world, China, a new logistics operation called the indirect cross-border supply chain model has recently emerged. The primary idea of this model is to reduce logistics costs by storing goods at a bonded warehouse with low storage cost in certain Chinese regions, such as the Pearl River Delta (PRD). This research proposes a performance measurement system (PMS) framework to assess the direct and indirect cross-border supply chain models. The PMS covers four categories including cost, time, quality and flexibility in the assessment of the performance of direct and indirect models. Furthermore, a survey was conducted to investigate the logistics performance of third party logistics (3PLs) at the PRD regions, including Guangzhou, Shenzhen and Hong Kong. The significance of the proposed PMS framework allows 3PLs accurately pinpoint the weakness and strengths of it current operations policy at four major performance measurement categories. Hence, this helps 3PLs further enhance the competitiveness and operations efficiency through better resources allocation at the area of warehousing and transportation.  相似文献   

6.
为了研究城市群交通网络特性,运用ICN dual approach方法构建了以美国东北部大西洋沿岸城市群、日本太平洋沿岸城市群、英国伦敦为核心的城市群、长江三角城市群、京津唐城市群、珠江三角城市群等国内外典型城市群交通网络模型,使用MATLAB和VC++分别对它们的平均度、网络密度、n-聚集系数、平均最短路径、随机网络聚集系数、随机网络平均最短路径、网络结构熵、全局系数等网络特性指标进行计算和比较分析,得到以下结论:a)六个城市群交通网络都具有小世界性而不具有无标度性,一般可以推论城市群交通网络只有小世界性、不具有无标度性;b)六个城市群交通网络都存在着极少道路介数很大,对整个网络的整体性、连通性和安全性意义重大;c)六个城市群交通网络中珠江三角城市群交通网络的整体效率最高,日本太平洋沿岸城市群交通网络结构熵最小,表明其最有序。  相似文献   

7.
量化联合国可持续发展目标SDG 11.3.1“土地消耗率与人口增长率的比率(LCRPGR)”有助于了解城市扩张与人口增长之间的关系,为城市国土空间规划和人口城镇化调控提供数据支撑,并且对指导决策者制定城市增长计划至关重要。基于土地利用产品、夜间灯光数据和人口普查数据,提取了城市建成区,利用地理加权回归模型测算了珠三角地区1 km×1 km格网尺度人口密度。依据SDG 11.3.1指标元数据中定义和公式,对珠三角地区可持续发展进行了可靠评价。结果显示:①1990~2010年珠三角建成区面积扩张4.6倍,城区人口增长3.7倍;②1990~2010年珠三角的LCRPGR值由0.71增长到2.01;城市扩张速度与人口增长速度并非是成比例协调增长关系;③建成区的扩张主要是由耕地和农村居民用地转换而来。综上,自2000年后珠三角地区土地消耗率已经超过人口增长率,城市扩张速度与人口增长速度并非是成比例协调增长关系,二者的差异在增大,应当引起一定注意。  相似文献   

8.
Abstract: Logistics service providers are professionals who serve clients such as manufacturers, raw material suppliers, distributors, retailers and shippers within the supply chain. Traditionally, the formulation of logistics strategies to execute various logistics services has been based solely on experience. In this paper, an intelligent case-based logistics strategy system (CLSS) is designed to help logistics service providers to develop strategies under various customers' demands. The proposed system, which is suitable for use in warehouse operations in the Hong Kong/Pearl River Delta region, enhances the effectiveness of logistics strategies formulations by integrating case-based reasoning technology seamlessly with various data management software such as a data warehouse, on-line analytical processing and a multidimensional database management system. Through applying CLSS in Eastern Worldwide Company, the resource utilization is maximized while work efficiency is greatly enhanced. As a result, the overall logistics operations are smoothened significantly.  相似文献   

9.
阐述应用多源遥感数据及多目标空间分析手段,研究珠江三角洲地区土地利用变化驱动的非点源污染与该区水质环境演变的方法.充分利用不同遥感数据特点,有效融合高、低空间分辨率数据,将进一步提高土地利用变化动态遥感监测能力.充分利用珠江三角洲地区近年来土地利用土地覆盖研究成果,将有助于分析非点源污染驱动因子与珠江河口及邻近水域水质...  相似文献   

10.
This paper introduces a model and corresponding software for modeling China's Energy Requirements and the CO2 Emissions Analysis System (CErCmA). Based on the input–output approach, CErCmA was designed for scenario analysis of energy requirements and CO2 emissions to support policymakers, planners and others strategically plan for energy demands and environmental protection in China. In the system, major drivers of energy consumption are identified as technology, population, economy and urbanization; scenarios are based on the major driving forces that represent various growth paths. The input–output approach is employed to compute energy requirements and CO2 emissions under each scenario. The development of CErCmA is described in a case study: China's energy requirements and CO2 emissions in 2010 and 2020 are computed based on the input–output table of 1997. The results show that China's energy needs and related CO2 emissions will grow exponentially even with many energy efficiency improvements, and that it will be hard for China to maintain its advantage of low per capita emissions in the next 20 years. China's manufacturing and transportation sectors should be the two major sectors to implement energy efficiency improvements. Options for improving this model are also presented in this paper.  相似文献   

11.
With the development of urbanization in China, construction land (CL) expansion is obvious, and urban heat island (UHI) is becoming more and more serious. Many scholars have shown a strong interest in the study of UHI caused by land expansion, but less attention has been paid to the coupling relationship between CL expansion and high-temperature area (HTA) expansion during the process of urbanization. This study obtained the land surface temperature (LST) data of China’s three major urban agglomerations (CTM-UAs) in 2000, 2005, 2010 and 2015. Then this paper used overall coupling model and spatial coupling model to reveal the coupling relationship between the CL expansion and HTA expansion of CTM-UAs in different periods. The results showed that: (1) From 2000 to 2015, the trend of CL expansion and HTA expansion in CTM-UAs was synchronous; (2) The distance between the CL barycentre and HTA barycentre in CTM-UAs was shrinking, the spatial overlap was constantly strengthening, and the overall coupling was constantly strengthening. And the highest value of the overall coupling was reached in 2015; (3) The number of grid units of very strong coupling and strong coupling increased with fluctuation in Beijing-Tianjin-Tangshan Urban Agglomeration (BTT), that in Yangtze River Delta Urban Agglomeration (YRD) was increasing, and that of Guangdong-Hong Kong-Macao Urban Agglomeration (GHM) has gone through the process of increasing to decrease.  相似文献   

12.
油井、风机和道路是黄河三角洲区域的主要人工地物,明确其时空特征对保障黄河三角洲的生态安全具有重要意义。利用Landsat、SPOT、高分二号等中、高分辨率卫星影像,提取并建立2000年和2015年黄河三角洲主要人工地物分布数据集,使用核密度法、平均最近邻法、加权分析法、克里金插值法和空间自相关分析法分析2000~2015年黄河三角洲人工地物的时空特征。结果表明:(1) 2015年风机空间分布具有不均衡性,呈现两大核心区为主、3个小集聚区为辅的空间分布格局,总体呈西北—东南走向,空间集聚特征明显;(2) 2000年和2015年油井空间分布具有不均衡性且存在时间变异特征,2000年油井呈现两大核心为主,团块成片分布为辅的空间分布格局,2015年油井呈现三大核心区为主、核心区周围油井呈鞍状分布的空间格局特征;(3) 2000~2015年黄河三角洲路网密度不断提高,空间集聚特征明显,路网密度高值主要分布在黄河三角洲中部地区,并呈现向西部和南部扩散趋势。总的来说,黄河三角洲地区人工地物数量大、分布范围广、增长速度快,对自然保护区的生态安全造成了巨大威胁。通过识别和分析黄河三角洲人工地物及其时空特...  相似文献   

13.
The Pearl River Delta is experiencing very fast urban growth in recent years which has caused rapid loss of the valuable agricultural land in this fertile region. There is a great need to monitor the rapid urban expansion using remote sensing for urban planning and management purposes. However, it has been well recognized that there is significant over-estimation of land use change in using multi-temporal images for change detection because of inadequate creation of classification signatures. This paper presents a principal component analysis of stacked multi-temporal images method to reduce such errors. The study demonstrates that this method can reduce errors in change detection using multitemporal images and provide a very useful way in monitoring rapid land use changes and urban expansion in the Pearl River Delta and other parts of the world.  相似文献   

14.
The patterns of urban sprawl over a 20-year period presented in the study indicate unplanned development in the urban agglomerations of Ranchi, Jamshedpur and Dhanbad. The visual interpretation of Landsat (1986, 1991, 1996 and 2001) and IRS-P6 (2005) was used to map land use/land cover and analyse urban sprawl. The saturation of urban areas within municipal limits, along with pressure from the growing population, resulted in the densification of the core urban areas within Dhanbad and Jamshedpur. Comparatively, Ranchi exhibited a very high rate of built-up growth with a reducing population density, indicating a low density of built-up development. The development of built-up land at the expense of agricultural land in Ranchi Urban Agglomeration indicates poor land-transformation practices. An area of 103.6 km2 (165.66% growth) was transformed to built-up land in these cities during 1986–2005. Any future built-up development of these agglomerations should involve the use of the government city development plan.  相似文献   

15.
Green Logistics (GL) has emerged as a trend in the management of the distribution of goods and the collection of end-of-life products. With its focus on maximizing the economic and environmental value by means of recycling and emission control, GL contributes to the sustainable development of industry but also requires a more comprehensive transportation scheme when conducting logistics services. This study is motivated by the practice of delivering and collecting water carboys. In this paper, a Genetic Algorithm-based optimization model (GOM) is proposed for designing a green transportation scheme of economic and environmental cost efficiency in forward and reverse logistics. Two vehicle routing models with simultaneous delivery and pickup (full or partial pickup) are formulated and solved by a Genetic Algorithm. A cost generation engine is designed to perform a comprehensive cost comparison and analysis based on a set of economic and environmental cost factors, so as to examine the impact of the two models and to suggest optimal transportation schemes. The computational experiments show that the overall cost is evidently lower in the full pickup model. Notably, the impact of product cost after recycling and reusing empty carboys on total cost is more significant than the impact of transportation cost and CO2 emission cost. In summary, the proposed GOM is capable of suggesting a guidance for the logistics service providers, who deal with green operations, to adopt a beneficial transportation scheme so as to eventually achieve a low economic and environmental cost.  相似文献   

16.
Understanding spatial distribution of urban clusters at regional and national scales is increasingly important for many fields especially urban planning.Previous Studies have demonstrated urban built\|up areas can be derived from stable nighttime light satellite (DMSP\|OLS) images.Population and economic variables (i.e.GDP) have been proved significant positive correlations with nocturnal light brightness.However,less studies focused on the spatial distribution of extracted urban built\|up area.an improved DBSCAN algorithm is proposed to cluster the urban objects extracted from nighttime light image in different scales based on density,of which our urban spatial clusters are proved corresponding with urban agglomerations identified by statistical data.The traditional DBSCAN method is based on points which is not the same case with urban objects.The inclusion relation is refined,assuming that only if all the vertexes of each polygon are within the given distance,it is included in the area.Moreover,the parameters for the DBSCAN clustering model are determined by valleys of distances of every objects to classify urban spatial clusters.Besides,in a larger scale,the clustering results imply the different patterns of urban agglomerations on both sides of the Huhuanyong Line.   相似文献   

17.
In this paper we extract the morphological boundaries of urban agglomerations and characterize boundary shapes using eight fractal and nonfractal spatial indexes. Analyses were first performed on six archetypal theoretical cities, and then on Belgium’s 18 largest towns. The results show that: (1) the relationship between the shape of the urban boundary (fractal dimension, dendricity, and compactness) and the built morphology within the urban agglomeration (fractal dimension, proportion of buildings close to the urban boundary) is not straightforward; (2) each city is a unique combination of the morphological characteristics considered here; (3) due to their different morphological characteristics, the planning potential of Flemish and Walloon cities seems to be very different.  相似文献   

18.
韩正超  张有云  黄文霞 《软件》2020,(3):149-152,241
作为支撑我国国民经济快速发展的基础性、战略性产业之一的物流业,其发展水平极大的影响着一个城市的整体发展。济南市是山东省省会城市、济南都市圈核心城市,能过合理预测济南市的物流需求对于规划城市经济圈物流发展有着至关重要的作用。本文通过建立物流需求规模预测指标体系,并以济南市的历年数据建立BP神经网络模型,进行济南市物流需求预测,为其物流发展规划提供一定的参考。  相似文献   

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针对当前多区域物流中心选址需建立配送中心个数不定、位置、覆盖范围不明的问题,本文提出了一种改进的k-means聚类算法,以城市经济引力模型为基础,将城市运输距离与居民消费能力的指标相结合,重新定义对象之间相似性度量的距离因子.并将密度思想引入k-means算法,提出类内差分均值的概念确定最优聚类数.实现分区后,分别在这些区域中利用重心法对配送中心进行最终的确定.最后实例分析了在西部地区37个城市创建物流配送中心的选址过程,并通过和传统的k-means聚类的选址结果对比,说明改进后的算法不仅可以节省配送时间,而且大大降低了运输成本,有很好的经济利用价值.  相似文献   

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