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.     

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。     

Changes in the relationships between transport,communications and urban form

Transport, communications and urban form cover an overlapping area of rising academic and practical concern. This paper traces several of the many themes brought together under different professional banners, and shows how a confluence of interest is emerging.The themes are the developments in urban planning analysis, transport and time use studies, telecommunications and industrial location, all of which contribute to the area of locational effects of improved telecommunications technology, and are affected by alterations in the nature of work and the uses made of time by individuals. The convergence of geographical, planning, transportation and communication developments now requires explicit investigation, as the timings of technological and theoretical developments appear to coincide with the emergence of a significant need to do so. Some of the gaps between present knowledge and expertise that need to be filled are specified.These include the investigation of the testing and use of current land use integrated analyses for road and development assessment, investigation of the nature and characteristics of work and education which are most affected by telecommunications and computer support, development of longitudinal monitoring methods for overall urban development leading indicators, exploitation of newly-available cross-sectional household and city data sets in conjunction with historical data for longitudinal investigations and forward projections, accounting for altered family structure and activity patterns and the anticipation and assessment of probable further technological change, which can and will undermine many current long term commitments.     

山区高速公路桥隧连接段直立高陡边坡防护

本文主要高以山区高速公路桥隧连接段直立高陡边坡防护施工技术方案的论证及比选,桥隧连接段的位置大多都所处地形地貌与地质状况相对比较薄弱环节,位于这种地形位置的边坡防护要求较高,且要满足该类型边坡防护的效果。根据工程实际因素,需要进一步加强和深化高陡坡隧道洞口与桥梁相接位置的安全防护勘察工作,经现场勘察及几种防护方案的必选与论证,试图从山区高速公路桥隧连接段直立高陡边坡防护方案优化设计的角度降低防护施工难度及成本。鉴于桥隧连接段及隧道洞口现状直立高陡边坡整体基本处于稳定状态,加接延长隧道洞口明洞工程,并采用SNS主洞防护网与被动防护网相结合的防护方案合理可行,该防护方案的施工工艺简单,易操作,施工成本与施工安全风险低。     

Experimental and Numerical Study on the Behaviors of Deep-Buried Water-Storage and Drainage Shield Tunnels北大核心CSCD

Deep-buried water-storage and drainage shield tunnels, which are different from road and subway shield tunnels in terms of computation theory, construction technology and operation maintenance, would bear high inner water pressure and large earth pressure. In view of the change of the bearing mode for the lining structure of water-storage and drainage shield tunnels, a full-ring test and numerical analysis are carried out to study the influence of inner water pressure, staggered joint assembly and bolt installation types on the behaviors of water-storage and drainage shield tunnels. The results show that the deformation of the straight-jointed water-storage and drainage shield tunnel varies greatly from the state of empty water to that of full water; and the vertical and horizontal convergence deformations of the tunnel with inner water pressure of 0.6 MPa are 2.2 times and 3.2 times of that without inner water pressure, respectively. The convergence deformation, and the maximum joint opening and bolt tension of stagger-jointed lining structure decrease by 15%-25% and 25%- 40%, respectively, compared with that of the straight-jointed water-storage and drainage shield tunnel. The bolts at the segmental joints will yield because of the increase of inner water pressure and the first occurrence of bolt yield phenomenon is located near the position on the lining structure which is under the action of maximum negative bending moment; because the failure of shield tunnel is always caused by the yield of joint bolts, this position is the weak point for the deep-buried water-storage and drainage shield tunnel. For the water-storage and drainage shield tunnel based on the connection with double rows of bolts, the bolts near the outer arc surface of segmental joints in the area of 90 degree in the vault and arch bottom can be removed; the bolts near the inner arc surface of the segmental joints within the 90 degree of the haunch must be installed, otherwise, the tensile force of the bolts at the segmental joint near the maximum negative bending moment will increase by 5%-14%. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

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。     

Performance measures and data requirements for congestion management systems

Many metropolitan areas have started programs to monitor the performance of their transportation network and to develop systems to measure and manage congestion. This paper presents a review of issues, procedures, and examples of application of geographic information system (GIS) technology to the development of congestion management systems (CMSs). The paper examines transportation network performance measures and discusses the benefit of using travel time as a robust, easy to understand performance measure. The paper addresses data needs and examines the use of global positioning system (GPS) technology for the collection of travel time and speed data. The paper also describes GIS platforms and sample user interfaces to process the data collected in the field, data attribute requirements and database schemas, and examples of application of GIS technology for the production of maps and tabular reports.     

中等跨度钢管混凝土桁架连续梁桥成套技术研究

交通运输部西部交通建设科技项目"中等跨度钢管混凝土桁架连续梁桥成套技术研究"依托雅西高速公路干海子大桥工程,从理论分析入手,结合调查分析,通过室内试验和现场测试的比较论证,提出了山区公路桥梁建设的新理念,开发了新的桥型结构及施工方法,研究成果可用于指导中等跨度钢管混凝土桁架连续梁桥的设计、施工及养护。     

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。     

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。     

基于认知行为方法改善睡眠及促进职工身心健康的研究──以中国铁路广州局集团有限公司为例

随着公司制改革,国铁正向现代运输经营型企业转型,生产力的快速发展和组织变革既是机遇也是挑战。有效调适身心,适应不断变化的环境,促进职工身心健康,已成为实施健康中国发展战略的需求。本文阐述了铁路企业关注职工身心健康的现实意义,分析了现阶段企业职工身心健康存在的突出问题及成因,记录了实践活动开展过程及收效,提出了相应做法和对策。经多年调查发现,睡眠问题已成为困扰职工身心健康的突出隐患,因此率先在铁路企业中引入失眠的认知行为疗法(CBTI),结合运用多种心理学方法,招募志愿者开展小组实验,以促进职工睡眠质量,提升睡眠效率。希望通过实践活动的推广和长期坚持,从根本上改善职工睡眠质量,提高身心健康水平,为铁路安全生产构筑"心"的屏障。     

浅谈高速公路美丽服务区的建设思路

构建美丽服务区应以绿色、低碳、循环发展、智慧化以及满足出行用户的多元化需求为出发点,从节能建筑、清洁能源应用、污水处理及循环利用、固废处理及循环利用、生态服务、人性化服务等环节综合考虑,从而提升服务区整体形象,加强服务区设施的人性化和标准化服务管理。本文从高速公路美丽服务区构建的必要性入手,探讨了从节能建筑、清洁能源应用、污水处理及循环利用、固废处理及循环利用、生态服务、人性化服务等方面构建美丽服务区。     

岩爆灾害研究与进展

为阐明岩爆机理,减少岩爆灾害,对岩爆的定义、分类、研究方法、特征、形成条件、预测方法及防治措施进行了系统的阐述。在前人工作的基础上,结合国内外已有的工程实例,对岩爆的时空特征和发生部位的岩性特征进行了剖析,对已有的岩爆研究方法和预测方法进行了合理分类和简要介绍,指出了部分研究方法的不足之处和预测工作的发展趋势。综合现有研究表明:岩爆分类采用的标准各有不同,其研究方法还具有改进的空间;适用于大部分工程的岩爆预测方法仍在探索和完善中;有效的岩爆防治措施有待进一步研究和优化。     

The relationship between segment-level built environment attributes and pedestrian activity around Bogota’s BRT stations

Few studies have examined the relationship between micro-scale features of the built environment and street segment usage. Micro-scale features of the built environment include the width of the sidewalk, the presence of amenities such as benches and trash bins, and the presence of crossing aids such as stoplights and crosswalks. This study employs segment-level primary data collected for 338 street segments in close proximity to one of 71 bus rapid transit stations in Bogotá, Colombia. We also use secondary data to control for area-level characteristics such as density, socio-economic stratum, unemployment, and crime. Factor and regression analyses are to use identify two dimensions of the built environment that are associated with higher levels of pedestrian activity: pedestrian-friendly amenities, comprised of wider and higher quality sidewalks and the presence of amenities such as benches, garbage cans, and bike paths; and connectivity, comprised of higher levels of road density, three- and four-way intersections, and density. In addition, we find greater pedestrian activity on segments with higher development intensity, with more mix of land uses, and with more crossing aids. Although the relationships identified are not causal, they are suggestive in terms of planning successful built environment interventions.     

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。     

The private and social cost efficiency of port hinterland container distribution through a regional logistics system

Increasingly, the debate on freight transport and logistics involves the challenge of sustainable development. Key objectives of sustainable or “green” freight logistics systems are the mitigation of negative environmental and human health effects of distribution operations and the realization of a major modal shift in transport preferences, while at the same time achieving internal generalized cost efficiency and quality of services. Pursuing these goals requires the introduction of a range of measures. These measures call for private and public actors to take up various initiatives and adopt policies. Usually, it is more effective to combine different actions into an integrated package of measures than to introduce single instruments in isolation.This article explores the nexus between sustainability and port hinterland container logistics. In particular, the methodology and results of an empirical analysis based on applications of a network programming tool called the “interport model” are presented and discussed. The model enables an examination of all possible effects on inland container flows and their associated internal and external costs due to public and private initiatives in the field of port hinterland container logistics. The empirical analysis aims to evaluate the impact of a set of simultaneous policy options and operational measures on the competitiveness and sustainability of hinterland multimodal distribution of import and export containers handled at the seaports of the Campania region located in Southern Italy. The loading units can transit through the dry port facilities (the so called “interports”) located in the same region and/or through extra regional railway terminals, before reaching their ultimate inland destinations or the seaports. The integrated package of measures simulated by means of the model includes: (i) infrastructure policy, (ii) improvements of rail services, (iii) regulatory changes in terms of customs authorizations and procedures, (iv) removal of technical and legal barriers to fair and non-discriminatory competition in the market of rail traction between regional seaports and interports, (v) new business models integrating container logistics operations between seaports and interports, and (vi) social marginal cost charging of transport operations. Once this package of instruments is introduced, higher private and social cost efficiency of port hinterland container distribution through the investigated regional logistics system can be achieved. For instance, it has been estimated an annual saving of the order of about 12,660 tonnes of CO₂ equivalent emissions from transport corresponding to an external cost reduction of 0.27 million euros from the observed real life situation, whereas the estimated saving in terms of air pollution (CO, NO_x, PM, SO₂, VOC) from transport is approximately 220 tonnes per year corresponding to an external benefit of 1.31 million euros.The most immediate priority appears to be the customs and intermodal logistics integration of seaports and interports by means of full implementation of the “extended gateway” concept as a way to increase the rail share of modal split and improve the overall cost efficiency of the system. In addition, the simultaneous introduction of a social marginal cost charging policy can contribute to make the regional interports a viable solution to expand the hinterland reach of the regional seaport cluster.     

交通运输能耗与排放统计监测平台及应用研究

在我国交通运输行业节能减排的背景下,本文以交通运输行业能耗特点与统计监测方法为基础,建立涵盖了公路客运、公路货运、城市公交、城市出租、水路运输、港口生产等行业的能耗碳排统计监测系统,分析了省级交通运输能耗与排放特点,明确了能耗数据统计对象与内容,并对能耗数据采集的方法进行了研究,建立了省级交通运输能耗统计监测系统,并以辽宁省交通运输为依托,对全省交通运输行业能耗统计监测系统进行了验证与应用,同时也为交通运输行业的节能减排提供了决策支撑和数据支持。     

道路车辆清障救援服务标准体系研究

道路车辆清障救援服务是保障道路运输安全畅通的重要组成部分,是道路交通安全保障失效情况下的一种补救措施。文中阐述了国内外道路车辆清障救援行业现状,分析了我国道路清障救援行业存在的问题。在此基础上,提出了道路车辆清障救援服务标准体系架构,以促进我国清障救援社会化、规范化、专业化、市场化。     

飞机轮迹横向分布测试系统的比选分析

文章介绍了国外机场相关轮迹横向分布测试系统,以及国内公路轮迹横向分布测试方法,通过分析各个测试系统的技术原理与系统自身的优缺点,并结合具体工程实例应用,综合考虑国内机场安全及运行管理要求,选取出一套最便捷、合适的机场跑道轮迹横向分布测试系统,为我国机场飞机轮迹横向分布数据收集提供参考。