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1.
The economies of China-Japan-Korea(CJK) are complementary, with their proximity resulting in the three countries having a high degree of interdependence with respect to trade. Currently, trade among these countries relies mainly on port-centered shipping. The development of the shipping network is integral for in-depth integration of CJK trade. This paper analyzes the overall characteristics, centrality, spatial structure, and vulnerability of the CJK shipping network using the methods of complex network analysis, blocking flow theory, and interruption and deletion of hub ports. The main findings are as follows: 1) The CJK shipping network has a small average path length and clustering coefficient, and its degree distribution follows a power-law distribution, which make the network present obvious characteristics of a Barabási-Albert scale-free. 2) The characteristics of the multi-center point of the CJK shipping network can alleviate traffic pressure. At the same time, the network shows a clear hierarchy in the port transportation system, with cargo transport relying mainly on the ‘hub port-hub port' connection. 3) The CJK shipping network is relatively stable. Compared with ports in Japan and Korea, the main hub ports in China have a greater impact on the stability of the shipping network, in particular those ports of the central coastal region, including Shanghai, Ningbo, and Lianyungang.  相似文献   

2.
Northeast Asia with China ,Japan and South Korea as the main components has drawn more and more atten-tion worldwide.Many scholars have researchec on the prospect of some alternatives of regional economic integration in Northeast Asia/or Yellow Sea Rin as its core area.In this paper the authors start with an introduction of the major arguments embracing Yellow Sea Rim regionalism,and attemptto identify the dynamics challenging the proposed approach-es of sub-regionalism of Northeast Asia.The paper firstly gives a brief review on the undate development of bilateral econom-ic exchanges,mainly Sino-Japanese and Sino-South Korean trades and direct investments with related contemporary is-sues.When the changing pattern of economic interactions is analyzed,special concerns are given to the possibility to real-ize the supposed potential of regional economic cooperation mainly based on economic complementarity among the related regions of China ,North Korea,South Korea,and Japan.The authors then made their major efforts on putting forward possible approaches of multilateral cooperation of three countries in the near future,that is ,deepened cooperation in select-ed sectors of industry and transportation and coordinated development among major cities.The authors stress that the develop-ment of sub-regional sectoral cooperation and the formation of interactive network of city-regions via social and economic interactions at local level are significant to the future regional integrated development in Northeast Asia..  相似文献   

3.
The study of air emission in maritime transportation is new, and the recognition of its importance has been rising in the recent decade. The emissions of CO2, SO2, NO2 and particulate matters from maritime transportation have contributed to climate change and environmental degradation. Scientifically, analysts still have controversies regarding how to calculate the emissions and how to choose the baseline and methodologies. Three methods are generally used, namely the ‘bottom up’ approach, the ‘top down’ ap...  相似文献   

4.
随着经济全球一体化快速发展,国际海运贸易的规模不断扩大,全球海运网络研究成为当前的研究热点领域。该研究是海洋运输、地理信息科学、数学物理、统计科学、复杂网络科学、大数据科学、计算机科学等多学科交叉领域共同关注的研究主题,对国家宏观战略与政策制定具有重要作用。本文总结了海运网络研究数据基础、理论模型和研究方法,包括数学物理统计理论方法,基于复杂网络的分析方法、数据挖掘理论方法等,然后从海运网络运输模式设计与优化,网络结构静动态特征,网络结构和交通流演化机制等角度总结海运网络的研究进展、分析所存在的问题,提出海运网络研究在跨学科跨领域研究方法的交叉、多源异构数据融合分析、理论与实际应用结合等方面的未来研究趋势。  相似文献   

5.
迁徙流作为互联网时代的新产物,信息流、资本流、交通流等流空间的基本载体,能客观地反映城市间地理行为关系,对于刻画城市网络结构具有重要意义。基于地级以上城市的百度迁徙大数据,本文尝试从全域和净迁徙的视角探索研究中国城市网络结构特征,对其网络的层级、关联关系和影响因素等进行挖掘提取。研究发现:① 全国城市网络呈现出稳定的、层级明确的三棱锥四顶点“钻石型”结构,与主要城市群的经济规模空间分布相吻合;② 区域网络表现出向高级别行政中心集聚的“核心—外围”放射状结构;③ 以省会城市为核心的典型小世界特征比较凸出,小世界网络的可达性和连通性较高;周口、阜阳、赣州、上饶、重庆等作为主要劳动力输出型城市,深圳、东莞、广州、北京、上海等城市成为了主要的外来人口聚集地,并形成了对应的人口就近输送网络关系;④ 城市的行政地位、经济规模、交通枢纽建设、劳动力资源等因素都对其网络控制力和影响力起到了决定性作用。最后,研究结合中国城市网络结构特征及其主要影响因素,提出相关政策建议,以期为中国城市网络结构均衡发展与建设提供借鉴依据。  相似文献   

6.
路网密度的研究是实施“一带一路”愿景之互联互通倡议的基础工作。“一带一路”顺应了世界经济全球化、一体化、多极化、信息化的趋势,牵连着蓬勃发展的亚太和发达的欧洲经济圈,带动中间国家的经济发展。在新形势下,如何通过交通基础设施建设推进丝绸之路经济带沿线区域间的互联互通、促进区域合作和经济发展,具有重要的现实意义。本文利用自发地理信息数据——OpenStreetMap(OSM)道路网数据,运用地理信息系统(GIS)空间分析技术,探究了“一带一路”陆路经济带辐射区域亚欧大陆的路网络密度和通行能力的空间分布格局,并分析了六大经济走廊节点城市的公路可达性空间格局。结果表明:“一带一路”陆路经济带的交通基础设施的发展存在着不平衡现象;路网密度和通行能力均呈现沿海高内陆低的空间格局;中亚、西亚地区和中南半岛地区成为道路水平落后带,限制了丝绸之路经济带资源整合与贸易畅通,建议在建设新跨国公路铁路同时,对原有老旧道路进行加宽加固等升级改造;全区域道路等级级配不合理;节点城市可达性具有明显的分异状况,六大经济走廊中83%的区域可达性在10 h以内。研究产出亚欧大陆1 km分辨率路网密度和通行能力数据集,发现了“一带一路”陆路经济带道路水平的薄弱区域,为“一带一路”陆路经济带的交通基础设施建设以及进一步的道路网研究提供了基础数据。  相似文献   

7.
城市交通与土地利用相互作用、相互影响。传统的城市空间模拟研究多关注交通对土地利用变化影响,缺少土地利用对路网空间形态影响的模拟。已有研究通常使用静态路网,不能表达土地利用与交通间的动态相互作用关系。本文以城市土地利用强度与城市道路网络空间分布间的正向关系,提出了基于城市土地利用强度的城市路网增长模拟模型。以唐山市为例,对其城市环路内的道路增长进行了模拟。结果表明,该模型能以城市土地利用强度的空间分布特征快速生成路网,反映城市土地利用对道路网络扩张的影响。模拟结果与实际路网具有高度的空间分布相似性。该模型可进一步与土地利用模拟模型结合,模拟城市土地利用与交通的动态相互作用。  相似文献   

8.
Land bridge transportation means transportation from one seaport to another by railway across continents instead of by ocean ship. At present, there are two common routes for using land bridge transportation in the world. One is Asia-America-Europe land bridge, the other is Europe-Asia land bridge.Eurasia land bridge has obvious advantages over Asia-America-Europe land bridge due to its shorter distance, shorter transportation time and special freight rate. China started Eurasia land bridge transportation business in 1980. It mainly used the mode of railway-railway combined transportation. The comparison between using Eurasia land bridge and using shipping transportation from China to Northern and Western Europe shows that Euraria land bridge transportation can save time and get foreign exchange in time, and commodity turnover will be speeded up. According to the port layout and railway network structure, China's land bridge transportation projects are proposed. They are Suifenhe project, Dalian project  相似文献   

9.
As an important component of China' transportation systems, for a long time, the insufficient performance of transport in QinghaiTibet Plateau(QTP) was a bottleneck restricting the economic growth and social development in this area. Nevertheless, the implementation of the western development strategy has accelerated the preliminary construction of comprehensive transport network since 2000. Due to the large area and significant geographical heterogeneity, there is a growing need to understand the relationship between transportation and economic development based on the perspective of spatial difference. By using GIS-based raster analysis and Geographically Weighted Regression(GWR) model, we investigated the spatial-temporal distribution of highway, railway and airport accessibility, respectively, and estimated the correlation and heterogeneity between transport accessibility and the level of economic development. Results revealed that:(1) Transport accessibility in the QTP improved by 53.38% in the past 15 years, which is specifically embodied in the improvement of both highway and railway.(2) Accessibility presented prominent differentiation in the space, increasing from west to east and reducing with the rise of elevation, specifically, the best accessibility area of the highway is below 4000 m above sea level, while the area with an altitude of over 4000 m has the lowest aviation time cost.(3) In general, the long weighted average time cost to critical transport facilities posed significantly negative effect on county economic growth in QTP, more positively, the adverse effect gradually weakened over time.(4) Obvious heterogeneity exists at the influence of different transport accessibility factors on the level of economic development, reflecting both in the horizontal space and altitudinal belt. Therefore, region-specific policies should be addressed for the sustainable development of transport facilities as well as economy in the west mountain areas.  相似文献   

10.
在“一带一路”沿线的65个国家中,46个国家拥有登记在案的港口,同时海上航运贸易占国际贸易总量的75%以上。为了充分了解“一带一路”沿线国家和地区航运贸易情况,评估国家、区域之间贸易往来关系,本文选取了2016年“一带一路”国家和地区船舶历史运动轨迹,首先基于规则判定的方法挖掘船舶停港事件,并以港口为主要节点,港口间货运往来事件为连接形成“一带一路”国际航运贸易网络。在此基础上,对贸易网络进行如下网络结构分析:① “一带一路”贸易网络基本属性统计,包括网络连通性、度分布、平均最短路径;② 网络节点中心度计算,主要采用Eigenvector Centrality评估分析贸易网中节点中心度;③ 结合社会网络挖掘中社区挖掘的概念,使用Fast Unfolding算法对贸易网络进行社区发现。可以看出,“一带一路”沿线国家和地区贸易往来错综复杂,港口之间呈现小世界网络特性;土耳其、俄罗斯、中国等国的港口影响力靠前;并且形成五大贸易社区,这些社区的分布和地理位置分布基本吻合,但仍然有部分国家受特殊贸易行为的影响,所属社区有所打破区域限制。本文旨在通过航运大数据构建贸易网络,在网络分析基础上,更好地评价节点影响力,更清晰地分析贸易网络结构,为“一带一路”战略更好地实施提供帮助。  相似文献   

11.
The transshipment is an important issue in the current marine transportation. This paper constructed a mathematical programming model to elaborate the transshipment port selection for the shipping company. This model is tested by the data collected from the ports of Hong Kong and Kaohsiung. The results show that this model can be used to explain the transshipment competition relationship between the ports of Hong Kong and Kaohsiung well. A sensitivity analysis was also executed. The sensitivity analysis results showed that both the port of Hong Kong and Kaohsiung should decrease the charges of port and increase the efficiency of loading and discharging. Based on the sensitivity analysis results, some interesting conclusions and helpful suggestions were obtained for the managers of the ports of Hong Kong and Kaohsiung to improve their port management.  相似文献   

12.
不同区域人群流量随时间的变化可以反映城市结构的空间差异。现有对于城市人群空间分布特性的研究大都以人群密度计算为基础,注重时空切片尺度,但是不能有效刻画邻域空间单元间流量变化的时空过程同步特性。本文提出一种基于基站间流量变化过程相似度的城市邻域基站流量变化同步性度量方法,量化分析不同区域的人群进出流量过程的相似程度,研究城市中具有相同人群流量变化过程的同步性区域空间分布规律。以深圳市为例,对城市同步性区域的空间分布与特点进行剖析。实验发现:计算同步性时参数选择需根据城市本身基站分布及流量特点分析,一般研究中,城市基站平均距离可作为邻近区域半径d,描述基站间流量变化相似度的特征阈值λ选取与邻近区域半径有关,半径越小,阈值取值越小。通过基站人群流量同步性得到的城市同步区域的空间分布不同于行政区域划分结果,同步区域面积小,划分更为精细;且规划级别越高的中心区,其范围内基站同步区域数目越多。最后,将同步区域结果与流量密度图对比,发现该方法不仅能够发现流量变化大的同步区域,并且能够发现城市中流量变化小的同步区域。本文提出的方法能量化衡量区域流量变化同步性并发现具有不同流量变化特点的同步性整体区域,对城市人群空间变化特点进行分析,可用于指导和评价城市规划与实际人群活动区域效果,以及城市服务设施布局等。  相似文献   

13.
集装箱运价的波动使得探讨运费保值的方法成为运输各方关注的重要问题。针对国际集装箱运输市场的特点,并借鉴国际上创设的多种运费衍生市场的经验,提出了集装箱运费保值市场的双层构架:创设以做市商为中心的、零售性质的远期运费合同市场,以利于中小型外贸公司、货代公司和船公司规避运价的不确定性,并建立集装箱远期运价协议市场,以便做市商、大货主和大船运公司在衍生市场进行运费保值。  相似文献   

14.
利用python程序语言开发了基于百度地图导航服务的批量路径时间查询平台,并结合最邻近设施时间和累积机会成本方法度量了居住单元与中心商业区(CBD)、与行政服务中心、与大型医院、与火车站、与飞机场的可达性;然后,着重对比分析了2种公交模式(有/无地铁)下公共服务设施可达性的差异。实验结果表明:① 与基于ArcGIS网络分析法等传统方法相比,基于“门到门”互联网路径规划服务API方法计算的出行时间成本能够较为精确、便捷地用于度量公共服务设施的可达性,避免了人工构建复杂路网数据集的工作量,而且更具时效性;② 融入地铁网络的公交模式不同程度上提升了居住单元至公共服务设施的可达性,尤其是地铁沿线“廊道”以及重要交通设施(如地铁站点)邻近区域最为显著;③ 居住单元至邻近CBD的可达性变化显著集中于0~30 min,30 min时间阈值内公交(有地铁)模式下累计的人口和面积分别是公交(无地铁)模式的1.7倍和2.2倍;④ 居住单元至邻近火车站的可达性变化显著集中于0~30 min以及30~60 min,30 min时间阈值内公交(有地铁)模式下累计的人口和面积分别是公交(无地铁)模式的8.9倍和3.0倍,60 min时间阈值内累计的人口和面积分别是公交(无地铁)模式的1.5倍和1.9倍;⑤ 居住单元至邻近飞机场的可达性变化显著集中于60~90 min以及90~120 min,90 min时间阈值内公交(有地铁)模式下累计的人口和面积分别是公交(无地铁)模式的12.6倍和6.6倍,120 min时间阈值内累计的人口和面积分别是公交(无地铁)模式的2.0倍和3.6倍;⑥ 居住单元至所属行政中心、至邻近大型医院的可达性在各个时间间隔及阈值范围内亦有相应幅度的改善。此外,运用本文的技术方法还可获得更完整、真实的其他交通模式(如汽车、电动车、自行车、步行等)接入城市公共服务设施的情形,为进一步研究非汽车模式下城市公共服务设施的可达性提供参考,促进城市公共交通可持续性的发展。  相似文献   

15.
This paper focuses on the economic development and urban morphology as well as its impact on the transportation system during the urban expansion of Shanghai in the last more than 20 years(1986-2008).Based on data from 3 comprehensive transport surveys of Shanghai since 1986,the changes in residential trip demand,vehicle use,and the spatial distribution of trips were studied to understand the demands on the transportation system.The factors contributing to those changes in transportation demand were discuss...  相似文献   

16.
1 Introduction The preferential flow tends to result in the loss of irriga- tion water and nutrients. The formation of the preferen- tial flow was caused by various factors, such as soil structure, tillage, worm cavity and root channeling rup- ture (Pot et al., 2005). Besides, frozen rupture can not be ignored in the northeastern China where the lowest tem- perature reaches -40℃ (Wang et al., 1993). There are several types of preferential flow, such as bypass flow, channeling flow and macro…  相似文献   

17.
China's global shipping connectivity had been somewhat overlooked as the bulk of related studies predominantly focused on the throughput volume of its own port cities. This article tackles such lacunae by providing a relational perspective based on the extraction of vessel movement archives from the Lloyd's List corpus. Two complementary analyses are proposed: long-term dynamics with all ships included(1890–2008) and medium-term dynamics focusing on container flows(1978–2016). Each analysis examines China's maritime connectivity in various ways and on different spatial scales, from the global to the local, in terms of concentration, vulnerability, and expansion. The main results underline the influence of technological, economic, and political factors on the changing distribution of connectivity internally and externally. In particular, China has managed to reduce its dependence upon external transit hubs, to increase the internal connectivity of its own port system, and to strengthen its dominance towards an increasing number of foreign nodes and trade partners through the maritime network.  相似文献   

18.
经济区域内支线机场选址模型   总被引:1,自引:0,他引:1  
当以城市群所组成的特定经济区域,其航空运输需求量足以达到一个适当规模的支线机场发展所需的业务量时,发展航空运输是必需的.在根据布局选址原则经验比选备选场址的基础上,以获得最佳经济效益为目标建立支线机场选址模型,并探讨参数确定和计算步骤,可用于机场选址的优化决策.  相似文献   

19.
Studies on long-term change of cropland is of great significance to the utilization of land resources and the implementation of scientific agricultural policies. The Korean Peninsula, adjacent to China, plays an important role in the international environment of Northeast Asia. The Korean Peninsula includes South Korea and North Korea—two countries that have a great difference in their institutions and economic developments. Therefore, we aim to quantify the spatiotemporal changes of croplands in these two countries using Landsat Thematic Imager(TM) and Operational Land Imager(OLI) imagery, and to compare the differences of cropland changes between the two countries. This paper take full advantage of ODM approach(object-oriented segmentation and decision-tree classification based on multi-season imageries) to obtain the distribution of croplands in 1990 and 2015. Results showed that the overall classification accuracy of cropland data is 91.10% in 1990 and 92.52% in 2015. The croplands were mainly distributed in areas with slopes that were less than 8° and with elevations that were less than 300 m in the Korean Peninsula. However, in other region(slope 8° or elevation 300 m), the area and proportion of North Korea's croplands were significantly higher than that of South Korea. Croplands significantly increased by 15.02% in North Korea from 1990 to 2015. In contrast, croplands in South Korea slightly decreased by 1.32%. During the 25 years, policy shift, economic development, population growth, and urban sprawl played primary roles for cropland changes. Additionally, the regional differences of cropland changes were mainly due to different agriculture policies implemented by different countries. The achievements of this study can provide scientific guidance for the protection and sustainability of land resources.  相似文献   

20.
广东省公路交通网络分形空间特征研究   总被引:2,自引:0,他引:2  
基于分形理论,以GIS技术为支撑,利用回转半径法测算了广东省全域及其所辖21个地级市公路交通网络半径维数DL、分枝维数Db和对应相关系数R2。依据广东省公路交通网络的特点,将其辖区分为四个子区域:珠三角、东部沿海、西部沿海和粤北地区,分析其半径维数和分枝维数的空间分布特征。研究表明,珠三角地区为广东省公路交通网络密度最大、结构最复杂、功能最完善、连通性最优的区域;以珠三角为中心,广东省公路交通网络分形半径维数和分枝维数随距离增大而衰减,沿海衰减程度微弱,粤北衰减程度较大。结果显示,半径维数和分枝维数结合能够更为合理系统地分析交通网络分形特征的时空差异特性。  相似文献   

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