Urban Railway Transportation Research Articles

Superconducting Magnetic Energy Storage (SMES) for Urban Railway Transportation

Superconducting Magnetic Energy Storage (SMES) for Urban Railway Transportation

Selective neglect of viral risk: Tokyo’s commuter trains during the COVID-19 pandemic

This article asks why Tokyo’s crowded trains were largely absent from official discourses of viral risk in Japan during the COVID-19 pandemic. While public transport environments were often framed as spaces of contagion in other countries, Japanese public health discourses instead tended to emphasize the viral safety of urban railway transport. Drawing on an analysis of media and expert discourse, auto-ethnographic fieldwork, and repeat interviews with commuters, this article examines the processes through which Tokyo’s urban railway network was extracted from discourses of viral risk. It identifies four factors that contributed to this: (1) dominant definitions of risk spaces in public health messaging, (2) trains’ integral role in the operation of socio-economic life, (3) elusiveness of public transport in the epidemiological data, and (4) a focus on “unruly” passenger conduct. This analysis of the selective treatment of viral risks is tied to a critical engagement with theoretical distinctions between “essential” and “existential” mobilities developed in prior anthropological scholarship on the pandemic. Exploring the discursive framing of pandemic mobility practices on one of the world’s most extensive urban railway networks, the article thus contributes to the anthropological study of mobilities and transport in Japan and beyond.

Prospects of autonomous railway transport development

The implementation of unmanned train control systems offers a number of advantages, such as increasing the capacity of railway lines and traffi c volumes, reducing the ‘human factor’, as well as reducing operating costs. The paper considers the challenges arising from the use of automatic train control systems, and presents the prospects for the implementation of automatic technologies in railway transport for various railway systems. The social and economic aspects of changing professional activities in railway transport are described. Grades of automation applicable to surface urban railwaytransport are presented. The issues of proving the functional safety of machine vision systems as part of the train traffic control system and determining their level of safety completeness are discussed. Examples of railway transport automation in Russia and other countries are given. Basic scenarios of automatic control system operation describing normal and abnormal situations are formulated. In conclusion, the levels of technological readiness of the reviewed solutions in the fi eld of train traffic automation are defi ned. The tasks faced by railway companies in implementing these technologies are outlined, and possible ways of overcoming obstacles to the introduction of automatic systems are proposed, taking into account the current political situation.

Research on Safety Assessment Indicators of Gas Extinguishing System for Urban Railway Transportation

Gas fire extinguishing system as a more widely used system in urban rail transit, its safety is related to the safety of passengers, lives and property. At present, there are few studies on the safety of gas fire extinguishing system, and there is no special standard to guide. In order to improve the safety of the subway gas fire extinguishing system, through a number of operating companies and manufacturers to conduct on-site research, and the use of theory and data analysis and other methods of gas fire extinguishing system safety indicators have been studied. Reliability analysis is carried out by using Fault Tree Analysis, and on this basis, the safety evaluation of the system is further quantified by identifying and analyzing the hazards of the gas extinguishing system and rating the risk of the system by using semi-quantitative method. The results show that the average working time index of the gas extinguishing system before hazardous failure is 173 years, and the average non-hazardous failure time is 173 years.

Practice of Cultivating Composite Talents for Intelligent Operation and Management of Urban Railway Transportation under the Trend of Digital Transformation

Practice of Cultivating Composite Talents for Intelligent Operation and Management of Urban Railway Transportation under the Trend of Digital Transformation

Energy consumption characteristics and rooftop photovoltaic potential assessment of elevated metro station

The current trend of urbanization has spurred the growth of the urban railway transportation sector, leading to increased carbon emission and environmental challenges. Applying renewable energy assisted power supply systems into metro stations is a feasible method for achieving decarbonization in urban transit systems. This study comprehensively reveals the real energy profile of a metro station on an hourly scale and establishes a multi-objective model to investigate the energy flexibility of the metro station with integrated battery energy storage for on-site renewable electricity consumption maximization. The results show that the elevated station has a photovoltaic potential of 20 %–25 %, in terms of self-sufficiency rate, when the rooftop of the station is fully utilized for photovoltaic array installation. Moreover, a photovoltaic-battery system in addition to a multi-objective mixed inter linear programming model is presented for the circumstance, there existing idle land around the station, to achieve a near-zero carbon station. It is indicated that the near-zero carbon station can be achieved with a minimum payback period of 11.5 years by optimizing the photovoltaic array size and battery storage capacity, leading to the annual carbon emission reduced from 457.1 to 91.4 tons. It is anticipated this study could provide reference for clean electrification and decarbonization in urban metro system.

Comparative analysis of damages and defects in rails of different railway transport systems

This article provides an analysis of the accumulation of detected damages and defects in the rails of two transportation systems - urban (metro) and mainline railway transport. Summarizing the analysis conducted, it should be noted that defects according to figures 10 and 11 are more often encountered on the tracks of the Kyiv Metro. At the same time, defects according to figure 27 are more often encountered on the tracks of the mainline railway transport, and it is also worth noting a wider range of defects, the share of which does not exceed 5%. According to the authors, this is related to the peculiarities of the conditions for operating transportation systems, particularly the load on the axle of the moving equipment, the movement characteristics, and other operational parameters. In order to make more accurate conclusions, it is necessary to perform a number of works using mathematical modeling methods to take into account the influence of individual parameters on the accumulation of defects and damages in rails.

Design and Evaluation of Linear Primary Permanent Magnet Vernier Machines for Urban Railway Transportation

Linear induction machine (LIM) is used as a driving machine in urban railway transportation because of its simple structure and mature technology. However, low thrust force and efficiency have always been a difficult problem to be solved. In the last decade, linear primary permanent magnet vernier machine termed as LVM in this paper has been extensively investigated owing to its potential application prospect in urban railway transportation. However, there is a lack of investigation on the feasibility of rendering the LVM the same size as existing LIM used in urban railway transportation. Therefore, in this paper, a large-sized LVM is designed and evaluated according to the requirement. Firstly, the LIM used in practical urban railway transportation are introduced. Secondly, the LVMs with the same size as the LIM counterpart are established by finite element method. Then, effects of consequent-pole Halbach permanent magnet structure, secondary tooth number and primary slot shape on performances are investigated. Thirdly, a LVM is optimized and compared with the LIM. The results revealed that the LVM exhibits higher thrust force and efficiency. Finally, a small-sized prototype of LVM is constructed to validate the simulation.

Urban Railway System Route Selection in Turkey Based on Socio-Economic and Technical Criteria Using the Analytical Hierarchy Process

With the increased importance of energy all over the world, new energy sources are needed to meet the energy demand. However, the solution to energy demand is not only finding new energy resources but also using currently consumed energy efficiently. Accordingly, decreasing the energy consumption in urban electric railway transport has become an important issue. Investment in urban railway transport is increasing continually because it is more economical, safe, and sustainable than other modes in local transportation. For new investments related to urban railway transport, decision-makers generally make an assessment that will include economic, demographic, and environmental impacts. In this study, a comprehensive top-down decision-making system for urban railway route selection was engineered by taking into account socio-economic criteria as well as technical criteria. In the context of surveys conducted with experts in the choice of railway system routing, five socio-economic criteria (passenger potential, construction cost, integration-access, zoning-ownership, travel time) and five technical criteria (vehicle energy consumption, regenerative energy, traffic operations, power supply system, efficient driving techniques) were determined. In the analysis, the analytical hierarchy process (AHP) method, one of the multi-criteria decision-making methods, was used to determine the best route among alternative routes based on all criteria.

The Integrated Kinetic Energy Recoup Drive (i-KERD): An Optimized Powertrain for EVs, HEVs and FCEVs

In this paper, a particular form of flywheel hybrid powertrain, namely, the Integrated Kinetic Energy Recoup Drive (i-KERD) is fully explored and its applications for EVs, HEVs and FCEVs in recent years to show the energy-savings and performance enhancement potential of this innovative powertrain technology. It is shown that the i-KERD is a small highspeed flywheel integrated into an e-CVT, or power-split hybrid drive. Under NEDC or WLTC, typically it can achieve some 40% energy savings and >50% gain in 0–100 kph acceleration due to effective regenerative braking mechanism of the integrated flywheel power system. In addition to its “peak-shaving” capability, the highly-efficient, long-life flywheel power on-board, is able to keep the kinetic energy of the vehicle fully recycled, rather than dissipated during braking. The i-KERD technology has also been applied to urban railway transportation (i.e., underground railway) and off-road heavy construction equipment, where regenerative braking plays a great role on energy efficiency.

Sudden passenger flow characteristics and congestion control based on intelligent urban rail transit network

The development of smart city is of strategic significance to the realization of modern society in China, and rail transit network is an important part of urban development. Currently, China's urban rail transport is at the bottleneck stage, and many medium-sized cities are facing a sudden heavy passenger congestion situation. Based on the next-generation innovation of the knowledge society, smart cities will maximize the use of new generation information technology in all fields of the city, and realize advanced urban informatization that realizes deep integration of informatization, industrialization, and informatization and helps to reduce urbanization and "disease in big cities." Improve the quality of urbanization, realize refined and dynamic management, and enhance the effectiveness of urban management and improve the quality of life of citizens. In order to ensure the safety of passengers, passenger flow control and optimization and upgrading of rail transit network become urgent. However, there are few researches in this field in China, so this paper will focus on the characteristics of sudden passenger flow and congestion control based on smart city rail transit network. First, in this paper, we systematically explained the relationship between smart cities and smart transportation and analyzed the need for sudden passenger flow control in urban railway transportation according to its characteristics. According to a study on the characteristics of sudden passenger flow, this paper believes that passenger flow comes primarily from large-scale activities, commuters, and individual emergencies, but is still predictable and controllable. For this reason, this paper studies the control scheme of sudden passenger flow congestion, which fully combines the characteristics of sudden passenger flow, and according to the characteristics of the treatment. This scheme is safe and reliable and has the advantage of controlling congestion from the source. In order to further test the actual effect of the passenger flow control scheme, the simulation experiment is carried out in the end of this paper. According to experimental data analysis, the passenger flow control method of this paper can effectively improve the existing rail transport congestion control in the case of sudden large-scale passenger flow, and the effect is remarkable, and most of them. Suitable for urban rail transport networks.

Hybrid Statistical-Machine Learning for Real-Time Anomaly Detection in Industrial Cyber–Physical Systems

Critical industrial infrastructures are currently facing increasing cyberspace threats in their underlying information and communication systems. The advanced monitoring, control, and management functionalities of the industrial systems firmly rely on the reliable and secure operations of the industrial control system (ICS) network. This article characterizes the ICS network traffic and presents a scalable and efficient solution for real-time ICS network traffic anomaly detection, considering various forms of ICS anomaly events. The events due to the cyberattacks, malicious operating behaviors, and network anomalies can be effectively detected without sophisticated computational requirements and retrieval of communication protocols. The proposed hybrid statistical-machine learning model integrates a seasonal autoregressive integration moving average (SARIMA)-based dynamic threshold model and a long short-term memory (LSTM) model to jointly identify the abnormal traffic patterns with low false omission rates. The proposed solution is extensively evaluated at a realistic ICS cyber–physical system (CPS) testbed, and the numerical results confirm its high detection accuracy and low computational complexity. Note to Practitioners—This article was motivated by the challenge of real-time anomaly detection in industrial cyber–physical systems (CPSs). The existing industrial control system (ICS) network anomaly detection solutions are generally carried out based on a single model based on the historian database and cannot dynamically classify the abnormal conditions in a real-time fashion. A novel hybrid statistical-machine learning model is developed that integrates a seasonal autoregressive integration moving average (SARIMA)-based dynamic threshold model and a long short-term memory (LSTM) model to jointly identify the anomalous events through traffic pattern analysis. The proposed anomaly detection solution can efficiently provide accurate detection for cyberattacks, malicious operating behaviors, and network anomalies while meeting the real-time requirements of ICS networks. The proposed solution can be deployed in the realistic ICS CPSs, e.g., the power generation system, gas pipeline systems, and urban railway transportation systems. The preliminary numerical results obtained from the ICS-CPS testbed suggested that it can provide high detection accuracy with low computational complexity and, hence, can be adopted with minimal deployment hurdles.

Dynamic interaction between rail vehicles and vibration-attenuating slab tracks

The ground vibration and noise induced by trains are among the most concerned issues in the field of urban railway transportation. Therefore, many types of vibration-attenuating slab tracks have been brough in urban railways to minimize train induced vibration and noise. Vibration-attenuating slab tracks usually have a soft support system than that of traditional slab tracks, which on the other hand affects the vehicle-track interaction. This paper presents a study on the dynamic interaction between urban railway vehicles and vibration-attenuating slab tracks, in which four typical elastic vibration-attenuating slab tracks including the resilient-fastener slab track, elastic-supporting-block track, ladder-type sleeper track and floating-slab track are considered. A three-dimensional dynamic model of a metro train running on different vibration-attenuating slab tracks is formulated. This model is capable of predicting the vehicle-track interactions under various wheel-rail excitations. The dynamic characteristics of wheel-rail interaction induced by impulsive, harmonic and random track defects of two metro vehicles travelling on the four vibration-attenuating slab tracks are compared in detail. The influence of track viscoelastic properties on vehicle-track interaction is reported. The results show that the properties of vibration-attenuating slab tracks have a significant effect on vehicle-track dynamic interactions. The dynamic responses of wheel-rail forces of the vehicles travelling on different vibration-attenuating slab tracks are significantly different. The elastic-supporting-block track has the best performance in absorbing mid- and high-frequency wheel-rail forces.

Green building certification of urban public railway transport systems for sustainable cities

The increasing consumption of energy and the greenhouse-gas emissions are challenges in the transport and building sectors. Compared to the other transportation types public railway transport systems are the most energy efficient regarding carbon footprint. Modern urban railway public transport systems have the significant advantages of large passenger capacity, punctuality, safety, going green in the urban environment and reducing carbon footprint, is a scientific consensus. However, the energy demand for railways are increasing in proportion to passenger load, require implementing innovative solutions for optimizing the energy consumption and reducing carbon emission. Leadership in Energy and Environmental Design (LEED) is a building rating system used worldwide. The credit categories of the LEED consist of seven different topics from the Energy and Atmosphere to Materials and Resources. In this study, the LEED certification application to railway station and facilities will be discussed mainly energy efficiency criteria.

Comparison Between Linear Induction Motor and Linear Flux-Switching Permanent-Magnet Motor for Railway Transportation

Linear induction motors (LIMs) have been extensively adopted in urban railway transportation given their nonadhesion thrust and simple stator structure. However, these LIMs undergo unfavorable power factor and efficiency considering their copper and eddy losses. Recently, linear flux-switching permanent-magnet motors (LFSPMs) have attracted the attention of researchers due to their high power density, simple structure, easy heat dissipation, high efficiency, and high power factor. However, so far, no quantitative comparison exists between LFSPMs and LIMs of the size 1:1 to prove the feasibility of LFSPMs to be used in railway transit systems. Therefore, a comparative analysis between the two motors is conducted in this paper. First, this paper investigates the LIMs for railway transit using the finite element method (FEM). Second, the LFSPMs for railway transit is designed and optimized. Third, the electromagnetic performance of the two motors is compared and analyzed through the FEM. Finally, a small-sized prototype of the LFSPMs is constructed to validate the FEM results. It is concluded that LFSPMs offer a favorable thrust force, have high efficiency, and high power factor but have large normal force and force ripple. Therefore, applying LFSPM requires a reliable supporting device and a shock absorber.

Experimental and Numerical Investigation on the Ultimate Vertical Bearing Capacity of U-Shaped Girder with Damaged Web

U-shaped girder has been extensively used for its excellent adaptability in the urban railway transit system. As an open thin-walled structure, significant difference of working mechanism exists between U-shaped girder and conventional section girder (e.g., T section or box section). The thin-walled web plays significant role in the flexural performance of U type girder particularly. Moreover, severe collision may occur between the moving train and the girder, and subsequently results in the decrease of the structural bearing capacity. In this paper, a full-scale test was carried out to examine the ultimate bearing capacity and the failure mechanism of the U-shaped girder, and a refined numerical model was developed to simulate the damage evolution and the failure process. It was shown that the flexural failure occurred on the U-shaped girder under vertical loads. In addition, the ultimate bearing capacity of the structure under different web damage conditions (e.g., web damaged region or damaged range) was studied by applying the displacement based lateral load on the flange of the U-shaped girder to simulate the damage caused by accidental train collision. The numerical results have shown that the damaged web greatly affects the ultimate bearing capacity of U-shaped girder, more severe bearing capacity descending occurs around the middle span rather than the beam ends. The damaged range (length) of the web has less influence on the falling amplitude of bearing capacity. It can be concluded that the major reason accounting for the bearing capacity decrease is that the original section is weakened by the web damage, and consequently results in the buckling of the damaged web and lead to the total failure of the structure. It is recommended that the lateral resistant design for the web should be taken into consideration to ensure the operation safety of the urban railway transportation.

Speed increasing scheme by using 3000v dc power supply for low-speed Maglev

Background: Low-speed maglev is usually designed to run at a maximum speed of about 100~110 km/h, the system does not have any advantage to the traditional urban railway transportation system at the aspect of running speed.
 Aim: Increase the speed of low-speed Maglev is an urgent task for future promotion.
 Methods: This paper presents a speed increasing scheme by using 3000 V DC power supply instead of original 1500 V DC.
 Results: Under this condition, the max output voltage of propulsion inverter could be doubled. For reason that the insulation of linear induction motor has enough margin, only small adjustment of motor is needed to adapt the doubled voltage.
 Conclusion: To calculate the performance of low-speed maglev while using 3000 V DC, a T-model circuit of single-sided linear induction motor is built, and the result shows that the maximum running speed could be increased to over 160 km/h. This scheme provides a promising way for speed increasing, and it’s a simple and economical approach to enhance the competitiveness of low-speed maglev.

도시철도 교통서비스가 주택가격에 미치는 영향

도시철도 교통서비스가 주택가격에 미치는 영향

Institutional Modelling of Integrated PPT System in Urban Agglomerations

Urban agglomerations (centres with gravitating settlements in the suburbs) are examples of overpopulated urban structure with almost permanent peak load. Selection of public transport is the fundamental issue in planning the expansion of the existing one, or in constructing a new form of urban public transport system. Achieving a higher level of using mass public transport can also be inspired by building intermodal terminals (e.g. bus-train/urban railways/-car). However, apart from the urban railway, funicular, bicycle subsystem and maritime transport should be included as alternative public transport modalities as well. According to the problem described in this scientific paper, the suggested model is that of integration of all forms of public passenger service with a unique organisation, unified payment collection, integrated timetable, all included into a unique information system. The results of research in this paper indicate that the first step of integration of the public passenger transportation implies founding regional transport administration.

도시철도 일반·급행 혼합 스케줄 작성을 위한 시뮬레이션 방법론

There has been much discussion of introducing express train service in urban railway transportation since the express train service was successfully launched in Seoul line 9. However the discussion is mainly focused on the infrastructure problem like how to install siding tracks or the corresponding costs. This study addresses the operational aspects in operating the express trains; for example, how to calculate of running times of express trains or headway between the trains, and then how to make up the timetable. These aspects have been found out by means of another special project. We suggest a simulation based approach to develop the mixed timetable. The approach consists of the several steps of calculating some fundamental times, adding the trains, and adjusting the arrival and departure times. The approach has some advantages that the running time and headway are automatically calculated within the simulation software so that the feasibility of timetable can be easily checked. We could yield a mixed feasible timetable of regular and express trains in the Seoul line 9 just by means of the suggested procedure.