高速公路互通改扩建线形布设难点及处理方法研究

互通式立交改扩建是高速公路改扩建工程的重点和难点,做好其改扩建线形布设非常关键。文章采用比较性分析与规律性总结相结合的方法,分析了高速公路互通式立交改扩建工程线形布设的主要影响因素和普遍遇到的难点与处理方法,并以呼包高速公路呼和浩特市互通改扩建工程为实例,介绍了其改扩建线形布设的难点与解决措施。     

Coordinating buses and rapid rail in the San Francisco Bay Area: The case of Bay Area Rapid Transit

This paper examines attempts by planners and policy makers to analyze and bring about the coordination of rail and bus transit in the San Francisco Bay Area. Drawing on studies and plans before and after the creation of the rapid rail system BART (Bay Area Rapid Transit), the author points to technical, analytical and political problems in attempts to link BART and buses. Some options and cautions are presented for planners considering route coordination, feeder buses, transfers and institutional arrangements to manage bus and rail services.     

南宁市公共交通发展存在的问题与对策研究

文章阐述了南宁市优先发展公共交通的必要性和紧迫性,介绍了国内外城市优先发展公共交通的做法和经验,并深入分析了南宁市公共交通发展的现状及存在的问题,探讨了加快发展南宁市公共交通的建议与对策。     

隧道超欠挖检测信息系统设计与实现

针对隧道超欠挖控制的关键因素检测及爆破后效果评价需求,研制了炮眼钻孔检测杆,开发了隧道超欠挖检测手机APP和B/S版隧道超欠挖检测信息化管理平台。利用手机APP连接钻孔检测杆及全站仪,对炮眼钻孔三维角度信息、位置信息及爆破后隧道断面进行检测、计算及传输,实现了隧道爆破过程检测及爆破断面效果评价,为后续动态调整爆破参数及超欠挖控制研究提供有效辅助。     

柳南高速公路改扩建石质高边坡施工方案浅析

受地形环境的影响和施工条件的制约,石质高边坡路段的施工方案一直是高速公路改扩建的重点和难点。文章结合柳南路改扩建工程石质高边坡路段的实际情况,通过介绍爆破技术类型及优缺点,提出科学合理的施工方案,并具体阐述静态爆破在施工中的应用以及相应的交通组织和安全措施。     

中小跨径桥梁高填土桥台合理结构型式浅析

文章通过分析阐述常见高填土桥台型式的优缺点、高填土桥台的主要病害及其产生原因,结合中小跨径桥梁高填土桥台的主要技术问题和设计原则,提出采用桩柱式埋置台作为中小跨径桥梁高填土桥台的通用结构型式,并对该结构形式的设计、施工要点进行了介绍。     

长输油气管道内腐蚀研究进展

针对长输油气管道的内腐蚀问题,总结了国内外油气管道内腐蚀研究现状、内腐蚀主要机理,并从输送介质、管材成分、输送工艺等方面对管道内腐蚀影响因素进行了分析。同时,结合国内外调研情况,介绍了长输油气管道内腐蚀控制标准和主要的防控技术,并对内腐蚀监测和直接评价技术进行了研究。在此基础上,介绍了开展管道内腐蚀研究的重要性及研究方向,为油气管道完整性研究和内腐蚀研究提供参考。     

Effects of wind strength and wave height on ship incident risk: Regional trends and seasonality

Oceanographic conditions like wind strength and wave height affect the risk of shipping incidents. Seasonal variations and trends in these effects are studied for weather-related incidents and pollution incidents, for six major ship types and for six regions across the globe. The employed database of more than five million observations combines information from various sources on oceanographic conditions, ship particulars, and incidents. The magnitude of wind and wave effects is found to vary by ship type, region, season, and period, and most of these effects are larger during the autumn and winter season and in recent periods.     

A bibliometric analysis on trends and characters of carbon emissions from transport sector

Transport sector’s substantial contribution to global greenhouse gas emissions has made it a growing area of study and concern. In order to identify trends and characteristics of carbon emissions research in the transportation sector we conducted a Bibexcel and complex network analysis for the period 1997–2016. In addition, we identify critical themes and contributions of research articles using h-index, PageRank and cluster analysis. We report contribution of countries, authors, institutions and journals, as well as performance of citations and keywords. Co-citing situations between different countries, authors, and institutions are also analyzed using network analysis. Between 1997 and 2016 we found a rise in publications on carbon emissions in the transportation sector and increased cooperation between countries, authors, and institutions. Authors from the USA, China and United Kingdom published the most articles and articles with the highest academic influence. Tsinghua University from China is the leading institution in carbon emissions research in the transportation sector. The most widely published author and cited author is Dr. He. We conclude our analysis by analyzing keywords and trends to suggest critical topic areas of future research. The systematic approach undertaken in this study can be extended and applied to other research topics and fields.     

广西甩挂运输发展对策研究

道路汽车甩挂运输在货物运输效率和节能减排效果上有显著的效益,正逐步得到社会各界的广泛关注。文章基于广西甩挂运输发展现状,预测分析广西发展道路甩挂运输的市场前景,并提出了广西发展甩挂运输的对策。     

轨道综合监控系统SIL评估中的风险管理

安全完整性等级SIL评估已经成为目前地铁安全系统工程的重要部分,也是国内外高度重视和着手研发的重要课题。风险管理是安全完整性评估中的重要环节,文中阐述了轨道交通综合监控系统中风险管理的要点和过程,包括风险分析范围、风险源识别、风险分析、风险评估、风险缓解与控制、风险跟踪与关闭,重点阐述了风险分析和风险评估的方法,为其他安全相关系统的开发和安全评估提供了参考。     

Understanding transport mode choice for commuting: the role of affect

This study examines the relationship between positive and negative user valence and transport mode choice behaviour. We integrate latent attitudes ‘affect’ and ‘salience’ into transport mode choice models using the framework of integrated choice and latent variable modelling and simultaneous maximum likelihood estimation methods. The results are consistent with findings in similar travel behaviour and behavioural economics literature. The study extends the findings of previous research and has demonstrated that user sentiments about public transport mode and salient public transport experiences have a significant impact on travel mode choice behaviour. It was found that private motorised users are more sensitive to overcrowding and anti-social behaviours on PT than active and PT travellers. Key attitudinal indicators influencing individual transport choice behaviour are established to guide public policy. The key indicators of Affect and Salience must be analysed and addressed through public policy to enhance PT user experience and develop services and facilities to increase the utility of PT in-vehicle travel time.     

基于灰色模糊理论的埋地输油管道腐蚀与防护势态综合评判

通过分析影响埋地输油管道腐蚀与防护势态的因素,结合改进的Delphi法和AHP法,综合考虑指标体系中各指标数据资料的可靠性及相对重要性,采用乘法合成的方式将可靠性指标和估价指标相结合,确定各指标的综合权重。结合灰色关联方法和模糊理论建立了综合评价模型,阐明了该方法的基本原理及计算步骤,并用算例说明了该方法的具体应用。该方法在理论上是科学的,而且很容易程序化,为埋地输油管道腐蚀与防护势态的综合评判提供了一种有效的手段。     

欧洲汽车轮胎滚动阻力及噪声测量方法

文章综述了欧洲关于汽车轮胎滚动阻力及噪声的测量方法,剖析了轮胎滚动阻力及噪声的测试设备、测试条件、测试过程以及测试计算方法和评价,为优化和改进我国的汽车轮胎滚动阻力和噪声测试提供参考。     

浅析MSTP与ASON在高速公路专网中的共存应用及发展

文章基于MSTP与ASON的技术特点,对MSTP与ASON技术在高速公路专网中的共存应用方式、方法进行分析,并阐述了MSTP与ASON技术的发展方向及意义。     

山区大跨径钢筋混凝土箱型拱桥的设计及施工技术研究

“山区大跨径钢筋混凝土箱型拱桥的设计及施工技术研究”项目通过对大量调查资料的分析研究,确定了山区大跨径钢筋混凝土箱型拱桥合理的设计参数、计算理论以及先进的施工技术措施,开发了新的材料、结构、工艺,形成了同类桥梁设计施工技术指南。本篇阐述了该项目的创新点、主要技术经济指标的先进性及取得的相关知识产权,指出了该项目在行业科...     

内河航道GIS与MIS集成技术推介

为了推进航运管理信息化,提高水路交通管理水平和服务能力,《＂内河航道GIS与MIS集成技术＂推广应用》项目研究基于西部项目《西部航道建设与管理监控技术研究及应用》的科技成果,建立了省级航道基础数据库和基于GIS的省级航道管理信息系统,对提高航道管理部门的航道信息化管理与航运服务水平具有重要的现实意义。本篇介绍了该项目的研究概况与实施内容,指出了其主要技术成果与创新点,并对该项目的经济效益与社会效益进行了评述。     

Urban transportation and equity: A case study of Beijing and Karachi

Development of mega cities of Pakistan and China has greatly been affected by the growth in urbanization and motorization. The uncontrolled rise in urbanization, motorization, exclusionary planning and disproportionate investment in transportation infrastructure has created a socio-economic imbalance, thereby challenging the issue of equity. This paper focuses on a comparative social equity assessment of urban development, characteristics of supply and demand of transportation and infrastructure systems and the impact of existing strategies over equity in the development of urban and transportation system of Beijing and Karachi. The paper concludes by suggesting some strategies for the development of sustainable and equitable urban transportation systems.     

岙山作业区VLCC应急临时锚位选址考虑因素和建议

岙山作业区作为国家战略石油储备基地及原油、成品油中转储运基地,各类油品船及超大型油轮VLCC靠离泊及装卸作业频繁,安全风险较高。本文从水上应急管理、节能增效,提升港口作业服务水平等角度分析建设VLCC应急临时锚位的必要性,以及从政策方面、通航因素、水深底质等方面分析了选址应考虑的因素,并提出了选址建议。     

Transit-oriented autonomous vehicle operation with integrated demand-supply interaction

Autonomous vehicles (AVs) represent potentially disruptive and innovative changes to public transportation (PT) systems. However, the exact interplay between AV and PT is understudied in existing research. This paper proposes a systematic approach to the design, simulation, and evaluation of integrated autonomous vehicle and public transportation (AV + PT) systems. Two features distinguish this research from the state of the art in the literature: the first is the transit-oriented AV operation with the purpose of supporting existing PT modes; the second is the explicit modeling of the interaction between demand and supply.We highlight the transit-orientation by identifying the synergistic opportunities between AV and PT, which makes AVs more acceptable to all the stakeholders and respects the social-purpose considerations such as maintaining service availability and ensuring equity. Specifically, AV is designed to serve first-mile connections to rail stations and provide efficient shared mobility in low-density suburban areas. The interaction between demand and supply is modeled using a set of system dynamics equations and solved as a fixed-point problem through an iterative simulation procedure. We develop an agent-based simulation platform of service and a discrete choice model of demand as two subproblems. Using a feedback loop between supply and demand, we capture the interaction between the decisions of the service operator and those of the travelers and model the choices of both parties. Considering uncertainties in demand prediction and stochasticity in simulation, we also evaluate the robustness of our fixed-point solution and demonstrate the convergence of the proposed method empirically.We test our approach in a major European city, simulating scenarios with various fleet sizes, vehicle capacities, fare schemes, and hailing strategies such as in-advance requests. Scenarios are evaluated from the perspectives of passengers, AV operators, PT operators, and urban mobility system. Results show the trade off between the level of service and the operational cost, providing insight for fleet sizing to reach the optimal balance. Our simulated experiments show that encouraging ride-sharing, allowing in-advance requests, and combining fare with transit help enable service integration and encourage sustainable travel. Both the transit-oriented AV operation and the demand-supply interaction are essential components for defining and assessing the roles of the AV technology in our future transportation systems, especially those with ample and robust transit networks.