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1.
本文从"坚持以人民为中心"的发展立场、解决不平衡不充分发展问题、融入国内国际双循环、构建更高水平一体化的城市—区域、综合交通体系建设以及机场布局规划制度创新等多个维度,阐述了长三角一体化背景下规划新建苏州机场的战略价值和社会实践意义。  相似文献   

2.
随着城市化的发展,珠三角城市交通能源消耗和碳排放迅速增长。为了探讨珠三角城市低碳交通的发展方向,本文采用LEAP模型,以珠三角的佛山市为例,模拟了不同情景下交通总量、陆运和水运的能源消耗、能源结构和碳排放由2011至2030年的变化情况;并据此提出了珠三角城市低碳交通发展对策。结果表明:水运在交通运输中所占份额逐渐被陆运替代,将形成陆运为主、水运为辅的交通模式;在交通总量、陆运和水运等的交通能耗及碳排放方面,低碳情景均小于基准情景,且呈水运小于陆运的态势;而清洁能源使用比重的增加则有利于交通领域的低碳发展。珠三角城市低碳交通发展需关注陆运交通,提高清洁能源在陆运中的使用比重,优化陆运与水运的交通布局,提高运输及能源利用效率。  相似文献   

3.
陈姗姗 《综合运输》2021,(3):19-22,95
推进长三角交通一体化规划落地是实施国家长三角一体化发展战略的重要基础。通过系统梳理上海多年空间规划实践经验,遵循城市群、机场群、近沪地区、全球城市多机场体系的逻辑思路,基于问题导向和目标导向,提出优先实现近沪地区民航紧密联系的规划突破点。临近地区民航协同,需要实现发展目标、通道枢纽、飞行保障、运输服务、货运物流、设施建设、重大项目、进度时序等多方面系统协同,建立契约关系,以市场化方式实践区域民航协同发展。  相似文献   

4.
As the global sulphur limit implemented by the International Maritime Organization (IMO) and the further development of sulphur emission reduction technologies, the effects of Emission Control Areas (ECAs) on reducing the sulphur emissions from ships will be reduced gradually. To explore the necessity of ECAs in the near future, this paper introduces the fictitious sulphur emission permit allocated to shipping carriers for our considered region. We propose an ECA location problem, which determines the location of ECAs in order to minimize the impact of sulphur emissions on human health, while satisfying the constraint on the fictitious sulphur emission permit. A mixed-integer linear programming model is proposed for our investigated problem. Numerical experiments are carried out by using our proposed model applied to China and Africa, where the sulphur emissions at different sites are estimated via the fuel consumption calculated by collecting data from liner carriers. Results show that, for the case of China, the Bohai Rim, the Yangtze River Delta and the Pearl River Delta have a high probability for establishing ECAs. For the case of Africa, the Guinea Bay and South Africa have a high probability for establishing ECAs.  相似文献   

5.
Ever since the Open Policy in 1979, there has been increasing socio-economic integration between Hong Kong and mainland China. The subsequent rapid export-oriented industrialization in the Hong Kong-Pearl River Delta (HK-PRD) region has given rise to rapidly growing cross-boundary container truck traffic (XBCT). From 1992 to 2003, the volume of XBCT rose from 1.5 to 4.7 million vehicles per annum. Hence, a new customs check-point, the Shenzhen Western Corridor (SWC), was built. With the development of SWC, how would XBCT drivers change their route-cum-customs (RCC) choice? What were their major considerations? How would the route choice among goods vehicle drivers differ from private car drivers? To what extent would the opening of new customs check-points change the RCC choice of goods vehicle drivers and resolve the uneven distribution problem of freight traffic? The current paper seeks to address these questions.  相似文献   

6.
姜阳  李政 《综合运输》2021,(3):38-41,60
城际铁路在国民经济和社会发展中发挥着重要作用,但在投资主体由"部省合作"向"地方主导"转变的过程中,出现了建设资金不足、资金筹措方式单一、可持续发展压力大等问题。本文通过对珠三角地区、京津冀地区、成渝地区等典型地区城际铁路建设投融资模式的调查研究,分析当前城际铁路投融资模式存在的主要问题,并研究提出相关的措施建议。  相似文献   

7.
文章从GPS静态测量、导线测量、高程控制测量等三个方面入手,详细阐述了红水河曹渡河口至桥巩段平面高程控制测量方法及实施情况。  相似文献   

8.
广西面临着西部大开发、CEPA、GMS、中国-东盟自由贸易区、泛珠三角经济圈、环北部湾经济圈等历史性机遇。如何抓住这一历史性机遇,乘势而上,构建广西面向东盟的国际道路运输业,是摆在我们面前的当务之急。作者从广西国际道路运输业的实际出发,分析了广西具有发展国际道路运输的独特优势和良好机遇,着重阐述了广西新一轮国际道路运输发展的战略布局,提出了加快广西国际道路运输发展的目标、方向和对策。  相似文献   

9.
ABSTRACT

Container shipping gives a rise of international trade since the 1960s. Based on navigation data start from the mid-1990s to 2016, this paper empirically analyses the spatial pattern of China’s international maritime linkages along the “twenty-first-century Maritime Silk Road”. We interpret such evolutionary dynamics in terms of growth, hierarchical diffusion and networking phases. Networking is a new stage of the evolution of the port system, which is approached based on the graph theory, complex network methods and geomatics, the paper discusses the networking’s basic characteristics: multi-hub spatial agglomeration, the connection of the network develops across space, functional differentiation and a division of labour appear among ports. Our results show that, while the scope of China’s maritime linkages had expanded overtime, more foreign ports become connected to the “Maritime Silk Road”. In addition, the external linkages of domestic ports tend to be dispersed, reflecting upon the decline of Pearl River Delta ports and the rise of Yangtze River Delta ports, with mixed evidence for the Bohai Rim region. Lastly, the analysis underlines the emergence of a polycentric shipping system, from the Hong Kong dominance to the more diversified Shanghai/Ningbo/Shenzhen configuration. Academic and managerial implications are included.  相似文献   

10.
Random coefficient logit (RCL) models containing random parameters are increasingly used for modelling travel choices. Willingness-to-pay (WTP) measures, such as the value of travel time savings (VTTS) are, in the case of RCL models estimated in preference space, ratios of random parameters. In this paper we apply the Delta method to compute the confidence intervals of such WTP measures, taking into account the variance–covariance matrix of the estimates of the distributional parameters. The same Delta method can be applied when the model is estimated in WTP space. Compared to simulation methods such as proposed by Krinsky and Robb, the Delta method is able to avoid most of the simulations by deriving partly analytical expressions for the standard errors. Examples of such computations are shown for different combinations of random distributions.  相似文献   

11.
结合上海长江隧道衬砌(φ15 m)1:1管片剪切试验,对试验数据进行分析,得出错动量随荷载变化的规律,进而得到环缝的剪切刚度计算公式及接触面的摩擦系数值.本文提出的管片环缝剪切刚度计算公式,可供今后类似工程参考使用.  相似文献   

12.
在建的钱江隧道是高速公路项目钱江通道及接线工程下穿钱塘江的控制性工程,隧址位于钱塘江人海口,工程地质条件及河段水文条件复杂.隧道过江段采用盾构法施工,隧道直径为15.0 m,是目前世界上最大的盾构法隧道.文章详细介绍了钱江隧道工程的建设环境、建设标准,以及隧道平面、纵断面及横断面布置等总体设计方案,并对超大直径盾构隧道结构及防水、盾构浅埋下穿河流、软土地层深基坑、盾构段立体化平行作业及综合防灾系统等关键技术进行了阐述.  相似文献   

13.
This paper presents a railroad energy efficiency model used to estimate the fuel economies for classes of trains transporting various commodities. Comparable procedures are used to estimate truck and waterway fuel consumption. The results show that coal unit trains are 4.5–5.0 times more energy efficient than movements in the largest trucks allowed in the eastern and western regions of the US, unit grain train movements in the central US are 4.6 times more fuel efficient, soda ash unit train and non-unit train shipments are 4.9 and 3.2 times more efficient, and ethanol unit train and non-unit train movements are 4.8 and 3.0 times more efficient. In terms of barge traffic, coal unit train and non-unit train are 1.3 and 0.9 times as energy efficient in the eastern US, grain unit train and non-unit train movements are 1.7 and 1.0 times more efficient from Minneapolis to the Gulf of Mexico, and grain unit train and non-unit train movements are 1.0 and 0.7 times more fuel efficient from the Upper Ohio River to the Gulf of Mexico.  相似文献   

14.
西气东输中卫黄河隧道是国家能源战略西北通道的咽喉工程,是西气东输备用通道和西气东输二线管道的主要通道,隧道内管道最大输气能力为470亿m3/年。文章介绍了西气东输中卫黄河隧道的工程地质、水文地质概况,以及设计原则和施工方法,总结出了油气管道水下隧道工程的设计和施工特点。  相似文献   

15.
The road transport sector is one of the major contributors of greenhouse gases and other air pollutants emissions. Regional emissions levels from road vehicles were investigated, in Mauritius, by applying a fuel-based approach. We estimated fuel consumption and air emissions based on traffic counts on the various types of classified roads at three different regional set ups, namely urban, semi urban and rural. The Relative Development Index (RDI), a composite index calculated from socio-economic and environmental indicators was used to classify regions. Our results show that the urban motorways were the most polluting due to heavy traffic. Some rural areas had important pollution levels as well. Our analysis of variance (ANOVA), however, showed little difference in emissions among road types and regions. The study can provide a simple tool for researchers in countries where data are very scarce, as is the case for many developing countries.  相似文献   

16.
利用桩基自平衡测试方法的试验结果,结合桩基设计规范,分析了黄泛平原地区桩基承载力的受力特点与影响桩基承载力的主要因素。试验与分析结果表明,黄泛平原地区第四系冲积物以亚砂土、亚粘土夹粉细砂为主,多层结构居多,上层多为粘性土。此种工程地质条件下,影响桩基竖向承载力因素较多,特别是桩基施工质量与桩基混凝土浇筑对桩基竖向承载力影响较大。  相似文献   

17.
大直径泥水盾构施工引起的地表沉降分析和对策   总被引:2,自引:0,他引:2  
鉴于武汉长江隧道工程复杂边界条件,为了确保盾构施工安全,保护周边建筑物,因此在施工过程中,必须根据隧道覆土厚度、地质条件、周边环境条件,合理设置与控制泥水压力,确定合适的同步注浆量等,以控制非正常的地层损失、避免灾害性地层损失、控制地表沉降、避免开挖面坍塌。本文结合武汉长江隧道盾构施工经验,对大直径泥水盾构推进中对周边环境的影响因素进行分析,并就地表沉降控制和预防灾害事故及事故处理的一些体会进行总结。  相似文献   

18.
螺丝岭柳江特大桥位于广西柳江县,是广西柳州市国道过境公路雒容至洛满段高速公路跨越柳江的一座特大型桥梁,本文主要介绍其大桥的挂篮施工方法。  相似文献   

19.
Road pricing policies are gaining prominence in EU countries. These policies have positive impacts leading to mobility patterns which are socially and environmentally more desirable, but they also have negative impacts. One negative impact is to be found in regional accessibility, due to the increase in generalized transport costs. This study presents a methodology based on accessibility indicators and GIS to assess the accessibility impacts of a road pricing policy. The methodology was tested for the Spain’s road network considering two road pricing scenarios. It enables not only the more penalized regions to be identified but also negative road pricing spillover effects between regions. These effects are measured in terms of accessibility changes occurring in one region produced by charges implemented in another region. Finally, the study of accessibility disparities (by calculating inequality indexes for each of the scenarios considered), provides policymakers with useful information regarding the impact of road pricing policies from the point of view of territorial cohesion.  相似文献   

20.
This paper presents a model that systematically integrates, for the first time, the association between a region's aviation near-midair collision risk and its traffic levels, its type and amount of air traffic control, and the complexity of its airspace. The model incorporates the tight interrelatedness (and correlation) between traffic, airspace complexity, and air traffic controller staffing. An estimation of the model using cross-sectional data on 143 U.S. airports in 1985 indicates that the frequency of reported near-midair collisions (NMACs) is positively associated with regional traffic and airspace complexity, despite the fact that busier, more complex regions generally have more air traffic controllers. Also, in regions governed by “terminal radar service areas” (TRSAs), the reported near-midair collisions are positively associated with the presence of more satellite airports than would be expected on the basis of traffic alone. Finally, deviations from controller staffing levels that would be expected on the basis of traffic and airspace complexity alone are significantly associated with variations in reported NMACs in terminal control areas but not in terminal radar service areas.  相似文献   

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