Greenhouse gas emission analysis and measurement for urban rail transit: A review of research progress and prospects

Rail transit plays a key role in mitigating transportation system carbon emissions.Accurate measurement of urban rail transit carbon emission can help quantify the contribution of urban rail transit towards urban transportation carbon emission reduction.Since the whole life cycle of urban rail transit carbon emission measurement involves a wide range of aspects,a systematic framework model is required for analysis.This research reviews the existing studies on carbon emission of urban rail transit.First,the characteristics of urban rail transit carbon emission were determined and the complexity of carbon emission measurement was analyzed.Then,the urban rail transit carbon emission measurement models were compared and analyzed in terms of the selection of research boundaries,the types of greenhouse gas(GHG)emissions calculation,and the accuracy of the measurement.Following that,an intelligent station was introduced to analyze the practical application of digital collaboration technology and energy-saving and carbon-reducing system platforms for rail transit.Finally,the urgent problems and future research directions at this stage were discussed.This research presents the necessity of establishing a dynamic carbon emission factor library and the important development trend of system integration of carbon emission measurement and digital system technology.

Function Analysis of Urban Rail Transit Smart Station

In order to make rail transit smart stations serve passengers better,the potential of smart stations should be optimized to reduce time cost,and relieve traffic congestion.In this paper,the construction of smart stations based on the management experience of a subway station and the benefits of smart stations were analyzed and discussed.The construction of smart stations,as well as the key technologies for the construction of smart stations,will aid in the automation and intelligent management of subway stations.

Future 5G-Oriented System for Urban Rail Transit:Opportunities and Challenges

As a development direction of urban rail transit system,the train autonomous circumambulate system(TACS)can operate in a safer,more efficient,and more economical mode.However,most urban rail transit systems transmit signals through industrial,scientific,and medical(ISM)frequency bands or narrow frequency bands,which cannot meet the requirements of TACS.As a promising solution,the 5th generation(5G)mobile communication provides more services for the future urban rail transit systems,and covers the shortages of exiting communication technologies in terms of capacity and reliability.In this paper,we first briefly review the research status of current train control system and introduce its limitations.Next,we propose a novel network architecture,and present new technologies and requirements of the proposed architecture for TACS.Some potential challenges are then discussed to give insights for further research of TACS.

Estimation method for a skip-stop operation strategy for urban rail transit in China

The skip-stop operation strategy （SOS） is rarely applied to Chinese urban rail transit networks because it is a simple scheme and a less universally popular transportation service. However, the SOS has performance advantages, in that the total trip time can be reduced depending on the number of skipped stations, crowds of passengers can be rapidly evacuated at congested stations in peak periods, and the cost to transit companies is reduced. There is a contradiction between reducing the trip time under the SOS and increasing the passengers＇ waiting times under an all-stop scheme. Given this situation, the three objectives of our study were to minimize the waiting and trip times of all passengers and the travel times of trains. A comprehensive estimation model is presented for the SOS. The mechanism through which the trip time for all passengers is affected by the SOS is analyzed in detail. A 0-I integer programming formulation is established for the three objectives, and is solved using a tabu search algorithm. Finally, an example is presented to demonstrate that the estimation method for the SOS is capable of optimizing the timetable and operation schemes for a Chinese urban rail transit network.

Optimization of train plan for urban rail transit in the multi-routing mode

The train plan of urban rail transit under multi-routing mode can be divided into three parts： train formation, train operation periods and corresponding train counts of each routing in each period. Based on the analysis of passen- ger＇s general travel expenses and operator＇s benefits, the constraints and objective functions are defined and the multiobjective optimization model for the train plan of urban rail transit is presented. Factors considered in the multi- objective optimization model include transport capacity, the requirements of traffic organization, corporation benefits, passenger demands, and passenger choice behavior under multi-train-routing mode. According to the characteristics of this model and practical planning experience, a three-phase solution was designed to gradually optimize the train formarion, train counts as well as operation periods. The instance of Changsha Metro Line 2 validates the feasibility and efficiency of this approach.

Importance Analysis of Urban Rail Transit Network Station Based on Passenger

Current urban rail transit has become a major mode of transportation, and passenger is an important factor of urban rail transport, so this article is based on passenger and the degree of the road network structure, calculating the point intensity of stations of urban rail transit, and then reaching a station importance by integrating many point intensities in a survey cycle time, and getting the station importance of urban rail transit network through concrete examples.

Industrial frequency single-phase AC traction power supply system for urban rail transit and its key technologies

To avoid stray current and maintain the benefit of no phase-split in the DC traction power supply system, an AC traction power supply system was proposed for the urban public transport such as metro and light rail transit. The proposed system consists of a main substation （MSS） and cable traction network （CTN）. The MSS includes a single-phase main traction transformer and a negative-se- quence compensation device, while the CTN includes double-core cables, traction transformers, overhead catenary system, rails, etc. Several key techniques for the proposed system were put forward and discussed, which can be summarized as （1） the power supply principle, equivalent circuit and transmission ability of the CTN, the cable-catenary matching technique, and the selection of catenary voltage level; （2） the segmentation technology and status identification method for traction power supply network, distributed and centralized protection schemes, etc.; （3） a power supply scheme for single-line MSS and a power supply scheme of MSS shared by two or more lines. The proposed industrial frequency single-phase AC traction power supply system shows an excellent technical performance, good economy, and high reliability, hence provides a new alternative for metro and urban rail transit power supply systems.

Landscape Design of Urban Rail Transit Complex Based on the Concept of Sustainable Development

On the basis of current development of urban rail transit complex in China,this paper proposed that it is necessary to build a complete landscape design system of urban traffic complex.Combined with the concept of sustainable urban landscape design,this paper explored landscape design of urban rail transit complex from the macroscopic,mesocopic and microscopic perspective,and analyzed many design cases to provide references for the sustainable landscape design of urban rail transit complex in China.

Design of Integrated Monitoring and Early Warning System of Urban Rail Transit Train Running State

The monitoring and warning of urban rail transit is the core of operation management, and the breadth and depth of the monitoring range directly affect the quality of urban rail transit operation. For the current domestic monitoring system, most of the critical equipments and technologies are introduced from abroad;it is diseconomy, and also causes hidden danger. Realizing the localization of monitoring and early warning system is imperative. Based on the analysis of the present situation of urban rail transit operation safety at home and abroad, the paper proposes to use integrated technology to design basic framework of monitoring and warning system of urban rail train, and puts forward the critical technologies to realize the system. Compared with the existing monitoring system, the integrated monitoring system has the characteristics of wide monitoring range, clear division of labor, centralized management, coordination and integration operation and intelligent management, and embodies the concept of people-oriented. It has scientific significance for future construction of domestic Integrated Monitoring and Early Warning System (IMEWS) of urban rail transit.

The Research of Urban Rail Transit Sectional Passenger Flow Prediction Method

This paper studies the short-term prediction methods of sectional passenger flow, and selects BP neural network combined with the characteristics of sectional passenger flow itself. With a case study, we design three different schemes. We use Matlab to realize the prediction of the sectional passenger flow of the Beijing subway Line 2 and make comparative analysis. The empirical research shows that combining data characteristics of sectional passenger flow with the BP neural network have good prediction accuracy.

Research on Obstacle Detection Method of Urban Rail Transit Based on Multisensor Technology

With the rapid development of urban rail transit,passenger traffic is increasing,and obstacle violations are more frequent,and the safety of train operation under high-density traffic conditions is becoming more and more thought provoking.In order to monitor the train operating environment in real time,this paper first adopts multisensing technology based on machine vision and lidar,which is used to collect video images and ranging data of the track area in real time,and then it performs image preprocessing and division of regions of interest on the collected video.Then,the obstacles in the region of interest are detected to obtain the geometric characteristics and position information of the obstacles.Finally,according to the danger degree of obstacles,determine the degree of impact on the train operation,and use the signal system automatic response ormanual response mode to transmit the detection results to the corresponding train,so as to control the train operation.Through simulation analysis and experimental verification,the detection accuracy and control performance of the detection method are confirmed,which provides safety guarantee for the train operation.

Modified stochastic user-equilibrium assignment algorithm for urban rail transit under network operation

Based on the framework of method of successive averages(MSA), a modified stochastic user-equilibrium assignment algorithm was proposed, which can be used to calculate the passenger flow distribution of urban rail transit(URT) under network operation. In order to describe the congestion's impact to passengers' route choices, a generalized cost function with in-vehicle congestion was set up. Building on the k-th shortest path algorithm, a method for generating choice set with time constraint was embedded, considering the characteristics of network operation. A simple but efficient route choice model, which was derived from travel surveys for URT passengers in China, was introduced to perform the stochastic network loading at each iteration in the algorithm. Initial tests on the URT network in Shanghai City show that the methodology, with rational calculation time, promises to compute more precisely the passenger flow distribution of URT under network operation, compared with those practical algorithms used in today's China.

Integrated Layout and Transfer of Urban Rail Transit Hubs

This paper is engaged in the research of urban rail transit hub integration and transfer.Firstly,this paper focuses on the space division,the aggregation form of hub subsystems,the spatial layout of hub subsystems,and the design of integrated functions to achieve an integrated layout.In addition,this study also conducted a selection of transfer classification and transfer station layout of urban rail transit hubs,with the aims to promote the improvement of the functions of urban rail transit hubs,the rationality of transfers,and to improve the service quality of the hub system which meet the demand of the public travel.

Two Network Structure Indicators for Conventional Public Transit

The significance of network structure indicators for the planning and management of conventional public transit is widely acknowledged.In order to improve and enrich the conventional public transit assessment system,two network structure indicators are proposed.Firstly,according to the obvious defects lying in the traditional no-linear coefficient,the realistic no-linear coefficient γRNL,a modified no-linear coefficient indicator,is put forward,which takes into account the effects of barriers in a city.Secondly,to cover the gap of an indicator which can reflect the coverage homogeneity of a transit network,the length dimension LDis proposed on the basis of Fractal Theory.Finally,a case study is applied to verify the validity and practicability of the two indicators in problem diagnosis using regression analysis.The results validate that γRNLcan evaluate the detour of bus lines more reasonably than the previous no-linear coefficient because it reflects the layout of bus lines,and LDcan represent the rate of change of the network density,adding a new member to the scheme of network structure indicators for public transit.

热烈庆祝《都市快轨交通》国际版——Urban Rail Transit被ESCI数据库收录

2019年4月,由北京交通大学和北京城建设计发展集团股份有限公司主办的英文刊Urban Rail Transit被Emerging Source Citation Index (ESCI)数据库正式收录,这是该刊入选的又一国际重要数据库,标志着Urban Rail Transit已在国际学术领域具有较大的影响力。ESCI数据库是汤森路透集团于2015年11月推出的一种新的期刊引文索引数据库,主要收录在学术领域具有地区性影响力的高质量期刊。

《都市快轨交通》国际版——Urban Rail Transit征稿

荣誉主编:施仲衡主编:韩宝明执行主编:周学松作者和读者在Urban Rail Transit发表文章将得到如下受益:·知名数据库收录·作者保留版权·获得全球关注与开放获取出版·无需版面费用·高质量和强大的审稿专家群·快速审稿、快速发表·引文跟踪且包含在书目数据库·没有页码长短的限制《都市快轨交通》国际版,Urban Rail Transit于2015年1月正式创刊,每年出版4期,是一个同行评审的、国际的、跨学科的开放存取期刊,在著名的学术期刊出版品牌SpringerOpen平台出版。Urban Rail Transit旨在为城市轨道交通领域的科学家、研究人员和工程技术人员发表原创的、有意义的论文提供一个平台,促进城市轨道交通领域的学术讨论和技术交流,也为轨道交通领域运营及建设的决策者、技术专家的决策提供参考。

《都市快轨交通》国际版——Urban Rail Transit征稿

荣誉主编:施仲衡主编:韩宝明执行主编:周学松作者和读者在Urban Rail Transit发表文章将得到如下受益:知名数据库收录作者保留版权获得全球关注与开放获取出版无需版面费用高质量和强大的审稿专家群快速审稿、快速发表引文跟踪且包含在书目数据库没有页码长短的限制《都市快轨交通》国际版,Urban Rail Transit于2015年1月正式创刊,每年出版4期,是一个同行评审的、国际的、跨学科的开放存取期刊,在著名的学术期刊出版品牌SpringerOpen平台出版。Urban Rail Transit旨在为城市轨道交通领域的科学家、研究人员和工程技术人员发表原创的、有意义的论文提供一个平台,促进城市轨道交通领域的学术讨论和技术交流,也为轨道交通领域运营及建设的决策者、技术专家的决策提供参考。

National Standards for Urban Rail Transit

In this paper, we suggest the creation of passenger service standards for urban rail transit. We put forward standards suited for China's actual conditions, aimed at meeting an international level of service based on customer-oriented principles.

Rational scale of urban rail transit network based on system dynamics

Urban rail transit(URT) has been playing an important role in urban sustainable development with its advantages of high speed,large capacity,high efficiency and low pollution.Estimating URT network scale is the key to ensure the scientificity and feasibility of its construction.The existing studies on rational scale of URT network have not dealt with the interaction of supply and demand.This paper describes the establishment of a system dynamics model of rational URT network scale determination,considering the interaction between URT construction and city social economic development as well as the dynamic equilibrium of capital supply and traffic demand,and the verification of the model validity by applying it to the case of Wuhan City's URT construction.