Determinants of air cargo traffic in California

Studies on the economic impacts of air cargo traffic have been gaining traction in recent years. The slowed growth of air cargo traffic at California’s airports, however, has raised pressing questions about the determinants of air cargo traffic. Specifically, it would be useful to know how California’s air cargo traffic is affected by urban economic characteristics. Accordingly, this study estimates the socioeconomic determinants of air cargo traffic across cities in California. We construct a 7-year panel (2003–2009) using quarterly employment, wage, population, and traffic data for metro areas in the state. Our results reveal that the concentrations of both service and manufacturing employment impact the volume of outbound air cargo. Total air cargo traffic is found to grow faster than population, while the corresponding domestic traffic grows less than proportionally to city size. Wages play a significant role in determining both total and domestic air cargo movement. We provide point estimates for traffic diversion between cities, showing that 80% of air cargo traffic is diverted away from a small city located within 100 miles of a large one. Using socioeconomic and demographic forecasts prepared for California’s Department of Transportation, we also forecast metro-level total and domestic air cargo tonnage for the years 2010–2040. Our forecasts for this period indicate that California’s total (domestic) air cargo traffic will increase at an average rate of 5.9% (4.4%) per year.     

兰州市区至兰州新区中快线建设方案研究

对兰州市区至兰州新区中快线建设条件分析,研究其合理的建设方案。通过对中快线在兰州至兰州新区3条规划交通廊道的作用和定位分析,采用交通量预测、调查选线、经济估算等方法,研究了中快线建设所涉及的若干关键技术问题,指出中快线建设是十分必要的,其南端宜同时建设3条连接线与兰州市区连接,北端应与兰州新区南绕城及经十三路连接,主线宜采用120km/h设计速度、双向六车道标准,可采用城市快速路或高速公路模式建设,且通道内具有预留轻轨建设条件。     

孤东油田海区泥沙淤积数值模拟

采用平面二维潮流泥沙数学模型,对孤东油田海域的潮流场进行了数学模拟,并在此基础上对泥沙运动及淤积进行了数值模拟研究。针对该海区海堤蚀退较严重的现状,提出了保滩促淤方案,模拟结果比较理想。     

湿陷性黄土地区铁路的主要技术问题及其工程措施

湿陷性黄土地基是基础工程中最为复杂的地基类型之一,采取可靠的工程措施以确保基础工程的安全稳定,是湿陷性黄土地区客运专线建设必须解决的技术难题。通过分析湿陷性黄土的主要工程特性,提出湿陷性黄土地区铁路工程的地基湿陷性、边坡稳定性、填料改良、黄土隧道变形、桩基负摩擦力等主要技术问题。在借鉴国内外已有的成熟经验和研究成果的基础上,湿陷性黄土地区铁路工程采取合理选择线路位置、科学确定工点方案、采取可靠的地基处理等措施,为铁路客运专线建设提供可靠的技术支撑。     

上海铁通城域传送网的转型

业务需求和技术进步推动着城域传送网的转型。简要介绍当前最新的光传送技术，并具体分析了上海城域传送网利用新技术的转型。     

高土壤电阻率地区轻轨综合接地网设置方法

1前言城市轨道交通系统具有的节能、快速、舒适、环保等特点,与快速路相对应,形成方便、快捷、发达的城市公交网络系统,由此推动了城市由单中心向多中心的发展。对此,各大城市都把轨道交通列入市政建设重点规划之中。目前,我国的轨道运输正处于大发展时期,而轨道中的供电系统作     

Estimating fuel demand elasticities to evaluate CO2 emissions: Panel data evidence for the Lisbon Metropolitan Area

This paper estimates fuel demand models for the Lisbon Metropolitan Area (AML) and uses the demand elasticities obtained to predict future levels of road transport CO₂ greenhouse gas emissions. Data for the municipalities constituting the AML and the period 1993–2010 are analysed using static and dynamic panel data models to measure the relative importance of fuel price, income, vehicle stock, the price of public transport, and the availability of urban and suburban rail networks on fuel demand. To the best of our knowledge, this is the first study in the Portuguese context to produce fuel demand elasticities for a specific metropolitan area, as opposed to the estimation of country-level aggregate elasticities. Our findings indicate that the elasticity of fuel demand with respect to fuel price ranges between −0.48 and −0.72 in the short run and between −1.19 and −1.82 in the long run. Income elasticities are found to range between 0.51 and 0.54 in the short run and between 1.26 and 1.37 in the long run. The elasticity of fuel demand with respect to vehicle stock (keeping population constant) is 0.57 in the short run and 1.43 in the long run. There is only weak evidence of a reduction in fuel demand as a result of a decrease in the price of public transport, and no effect of greater availability of rail networks. Based on the elasticities estimated, we predict road transport CO₂ emissions for the AML according to different macroeconomic scenarios. The results indicate that the emissions target is only achieved in the scenario of poor economic performance. In the presence of medium and strong economic growth, fuel prices would need to increase by about 7% and 11% per year respectively in order to meet the emissions target.     

交通系统仿真技术及在道路工程中的应用

交通系统仿真正逐步在城市道路及公路的规划和设计中得到应用。该文首先对交通系统仿真的主要研究内容、应用、分类、功能及相关的交通系统仿真软件进行了总体介绍;在此基础上,利用宏观仿真软件VISSUM对上海市临港新城芦潮港社区D3路的交通量进行了预测,其预测成果已被应用于D3路的设计。     

天津临港工业港区吞吐量水平和船型预测

临港工业型港区与一般商港的不同之处在于港区的直接经济腹地是临港工业区,港区主要服务于临港工业区内部企业在建设和运营期间的原材料、产成品和其他货物的运输,其中部分码头泊位也提供对外商业中转运输服务.针对天津临港工业区内企业的发展需求,重点研究临港工业港区的货物种类、流量和流向的发展趋势,预测未来几年港区的到港船型和吞吐量...     

连霍高速公路哈密—吐鲁番区间防风技术研究

在沿线风害成因、分布特征、基本风速对比分析研究基础上,确定连霍高速百里风区防风区段和防风标准,提出高速公路强横风路段采用柔性防风阻沙栅的防风措施,对于今后我国高速公路风害防控技术研究和高速公路安全、高效行车具有一定的指导意义和科学借鉴作用。