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41.
中国交通枢纽空间布局的评价、优化与模拟   总被引:5,自引:1,他引:4  
交通枢纽是综合运输体系的重要构成部分之一,合理的交通枢纽布局对于构建高效的综合运输体系具有重要的意义。交通枢纽的布局优化问题历来是交通运输工程学和交通地理学领域的一个研究热点。然而,当前有关交通枢纽布局的研究多局限于同一种交通运输方式,存在条块分割、重复建设乃至互相矛盾的问题。本研究立足于区域综合交通枢纽,研究首先确定影响交通枢纽布局的各评价指标,建立了由3 大类20 项指标构成的综合评价指标体系,以全国337 个地级行政区为基本单元,利用最大化覆盖模型,在科学评价综合交通枢纽布局潜力的基础上,识别出80 km、120 km、160 km和200 km 4 组服务半径约束下中国综合交通枢纽的最佳布局数量及其空间分布,从中归纳交通枢纽布局数量同目标函数值之间的一般规律,并最终优选出适合我国当前最优布局的42 个交通枢纽。研究对优选的42 个交通枢纽进行等级体系的划分和空间效应的模拟,分别从服务的空间范围和服务的社会经济要素进行分析,结果表明其所服务的国土面积、人口和GDP均优于国家规划集成的枢纽。  相似文献   
42.
Scientific development is an invaluable asset to a country.Policies and development modes should be carried out based on scientific findings not only in industry,but also in transportation infrastructure construction.Building an integrated transportation system,which is in line with the national requirements of China and supports sustainable socio-economic development,is a key strategic issue related to building a moderately prosperous society and achieving realistic goals of a medium-level developed country.Based on a systematic review of the advances in China’s transportation infrastructure over the last 60 years,this paper explores the main drivers of transportation development,including national policy,transportation structure,investment efficiency,and technological innovation.Analysis shows that China’s comprehensive transportation infrastructure construction since 1949 can be divided into five stages initiated by these drivers,which correspond to four transition modes:policy transition,structural transition,efficiency transition,and technology transition.The transition path of China’s transportation development shows that the dominant factors have changed,and the interval for each transition has shortened.With the implementation of the ’12th Five-Year Plan’,China’s transportation infrastructure construction is showing some new characteristics and facing a new development transition.Finally,this paper analyzes the trends in transportation development in China and concludes that technological innovation will be the main driving force to increase the transportation supply and service area in the future.  相似文献   
43.
The growth of peripheral ports to dominant hubs has been well documented in North America and Europe,and has led to the elaboration of several theoretical models.However,although changes in containerization growth have been taking place in the South and East Asia in recent years,particularly in China,only a few studies have fo-cused on this region.The Pearl(Zhujiang) River Delta(PRD) has a typical port system with hub and peripheral ports,and provides an excellent case for studying the Peripheral Challenge.This paper introduces the theoretical evidence of the Hayuth model and analyzes the evolution of the container port system in the PRD with five phases:1) phase I:preconditions for change and phase II:initial container port development in the 1970s and early 1980s;2) phase III:diffusion,consolidation,and port concentration in the middle and late 1980s;3) phase IV:the load center in the 1990s;and(4) phase V:the Peripheral Challenge since the late 1990s.The results illustrate that the Shenzhen port presents mounting challenges to the Hong Kong port,descending from a transshipment hub of China to a regional load center of Southeast China.Furthermore,this paper explores five points that have led to the evolution of the port system in the PRD:1) competition in the regional port systems;2) different interested parties;3) shift of investment strategies of in-ternational terminal operators;4) integration of shipping networks and reorganization of carriers;and 5) cost-based competition.  相似文献   
44.
王成金  金凤君  何丹 《地理研究》2013,32(3):431-440
自然灾害风险与防灾减灾研究的基础是灾区承险体的基本认知,如何对数量庞大、种类繁多的承险体进行科学分类是一直尚未解决的科学问题。在简要回顾国内外研究现状的基础上,本文分析了承险体识别与分类的几个关键问题,包括承险体的基础概念界定、关键问题厘清、分类原则等,根据统计方法、功能用途、基本属性和表现形态的差异,设计了由承险体集、承险体项、承险体类和承险体形式等4个层级组成的分类体系。按照这种分类体系,对区域自然灾害承险体进行了系统划分,形成了7个承险体集、19个承险体项、59个承险体类和若干承险体形式的分类方案。同时,对各类承险体与自然灾害的关系进行了分析,包括容易受害灾种和受灾方式。本研究丰富了自然灾害的理论研究,有利于自然灾害风险评估和防灾减灾工作的开展。  相似文献   
45.
以岩心的详细观察与测井录井资料综合分析为基础,通过岩石学特征和原生沉积构造等沉积相标志分析,确定鄂尔多斯盆地华池地区长6油层组厚层块状砂体属于半深湖内的深水重力流沉积体系。划分出内扇、中扇和外扇3个亚相,该区主要以中扇亚相最为发育;在深水重力流中识别出液化沉积物流、砂质碎屑流、近源浊流和远源浊流等沉积类型,建立了湖盆深水重力流沉积模式。砂质碎屑流沉积最为广泛,砂体厚度大,连片发育,具有最好的储集层物性,含油性好,是华池地区长6油层组最有利的储集层。  相似文献   
46.
柴达木盆地鄂博梁地区新近系物源分析   总被引:1,自引:0,他引:1       下载免费PDF全文
物源分析是沉积盆地研究的重要内容之一。在对柴达木盆地鄂博梁地区新近系相关资料调研的基础之上,对研究区碎屑岩的碎屑组分、岩屑类型、重矿物组合、砂地比和阴极发光平面分布特征进行分析,并结合地震资料,确定出研究区新近系物源方向:鄂博梁Ⅰ号构造带物源主要来自于北部的阿尔金山,而位于其西部的东坪构造带与鄂博梁Ⅰ号构造带物源区不同,其具有相对独立的物源区;鄂博梁Ⅱ号构造带属于混源区,同时受到2个方向物源的影响,分别是北部的阿尔金山方向和东北部的小赛什腾山方向,前者穿过鄂博梁Ⅰ号构造带到达该地区,是主要的物源区,后者穿过冷湖一、二、三号构造带到达该地区,为次要物源区;鄂博梁Ⅲ号构造带物源主要来自于东北方向的赛什腾山,其是穿过冷湖六、七号构造带到达该地区的,并未受到来自南八仙方向 “古鱼卡大型古河流三角洲”物源的控制。  相似文献   
47.
Before the emergence of modern modes of transport, the traditional road infrastructure was the major historical means of carrying out nationwide socio-economic exchange. However, the history of transport infrastructure has received little attention from researchers. Given this background, the work reported here examined the long-term development of transport networks in China. The national road network was selected for study and the 3500 years from 1600 BC to 1900 AD was chosen as the study period. Indicators were designed for the maturity level of road networks and an accessibility model was developed for the paths of the shortest distance. The evolution of the road network in China since the Shang Dynasty (1600 BC) was described and its major features were summarized to reveal long-term regularities. The maturity level of the road network and its accessibility was assessed and regions with good and poor networks were identified. The relationship between China’s natural, social, and economic systems and the road network were discussed. Our analysis shows that the road network in China has a number of long-term regularities. The continuously expanding road network follows a path of inland expansion especially towards the border areas. However, its coverage and accessibility are characterized by a core-peripheral configuration, which has close relationships with, not only the natural conditions, but also national defense and warfare. The centralization of national power, national land governance, postal transport, the transport of specialized cargos, and international trade are also related to the development of the road network. This research draws attention to the evolving regularities of transport networks.  相似文献   
48.
本文主要讨论了伊舒带的主要特征及其发展演化的历史过程。作者认为,晚期伊舒断裂带是郯庐断裂带的一个分支断裂,它经过了长期而复杂的演化过程,根据力学性质和活动方式的演变,演化过程被划分为四个阶段:最初是左旋剪切断裂,其后演变为压性断裂,第三期是右旋剪切断裂,最后形成右旋张剪性断裂。文中对最新期应力场进行了模拟,获得了伊舒断裂带邻近地区能量等值线 图和能量集中区,根据实验结果和历史地震资料对地震危险区进行了划分。  相似文献   
49.
采用面向对象的资源分类系统模型(WWTLM)对京津冀地区的13个城市及其所属的83个4A级和13个5A级旅游景区进行了分类,并以旅游圈理论和旅游域模型为基础,通过Visual Basic 6.0开发平台,利用专业GIS控件,采用集成二次开发的方式,对构建京津冀核心旅游圈进行研究。京津冀地区可成为旅游中心的城市有6个,分别为北京、天津、承德、廊坊、秦皇岛和石家庄,从旅游圈的级别和空间位置上看,北京旅游圈为一级旅游圈,承德,石家庄和秦皇岛为二级旅游圈,廊坊和天津为三级旅游圈,并进一步提出了构建以北京为中心的核心旅游圈,以此带动其他旅游圈共同推动京津冀地区旅游业的发展。  相似文献   
50.
鹿鸣钼矿床是小兴安岭—张广才岭成矿带上典型的特大型斑岩型钼矿床,矿体主要产于早中生代早期中细粒似斑状二长花岗岩内,矿化类型以细脉浸染状矿化为主。根据矿物共生组合及脉体穿插关系将鹿鸣钼矿床划分为4个成矿阶段:黄铁矿-石英阶段(Ⅰ),石英-辉钼矿阶段(Ⅱ),绿泥石-辉钼矿-石英阶段(Ⅲ),石英-碳酸盐阶段(Ⅳ)。成矿流体包裹体有3类:A型气液两相包裹体(L+V),B型含子晶三相包裹体(L+V+S),C型气相包裹体(V)。不同阶段流体包裹体的成分、均一温度、盐度等特征显示成矿流体由早阶段的高温、高盐度的H_2O-CO_2-NaCl体系逐渐演变为晚阶段的低温、低盐度的H_2O-NaCl体系。氢氧同位素特征显示成矿早阶段以岩浆水为主,随成矿演化有不同程度大气水的加入。根据矿床产出特征、矿物共生组合和流体包裹体特征,认为流体的沸腾作用和CO2等气相组分大量逸失是成矿流体形成矿床的主要因素。  相似文献   
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