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About this book

The proceedings collect the latest research trends, methods and experimental results in the field of electrical and information technologies for rail transportation. The topics cover novel traction drive technologies of rail transportation, safety technology of rail transportation system, rail transportation information technology, rail transportation operational management technology, rail transportation cutting-edge theory and technology etc. The proceedings can be a valuable reference work for researchers and graduate students working in rail transportation, electrical engineering and information technologies.

Table of Contents

Frontmatter

Transient Overvoltage Analysis of Traction Power Supply System with Neutral Sections in China High-Speed Railway Using a State-Space Model

This study proposes a complete state-space model of 2 × 25 kV traction power supply system with neutral sections in China high-speed railway where the catenary system is divided into several sections insulated with each other and is connected by neutral sections. First, the system is modularized by a neutral section module, a source module, autotransformer (AT) modules, series modules, and parallel modules which are represented with differential equations. Then the state-space model is built by means of slicing catenary system and combining with those modules. By calculating this proposed model, the transient processes of the electric train auto-passing trough the neutral section are analyzed. Transient overvoltages occurred due to high-frequency oscillations as the circuit topology changing in each process.

Xiaoqin Lv, Xiaoru Wang, Jiwei Zheng

Fault Diagnosis of Train Wheels Based on Empirical Mode Decomposition Generalized Energy

In this paper, a fault diagnosis method of train wheel based on empirical mode decomposition (EMD) generalized energy is proposed. First, EMD is applied to rail vibration signal to obtain the intrinsic mode functions (IMFs) and weight coefficients of each IMF are calculated. Then, quantitative value of EMD generalized energy is determined by calculating weighted sum of IMFs’ energy. Finally, the security domain threshold of EMD generalized energy is determined to distinguish faulted wheel. Experiment results by using simulation data showed that the proposed method can distinguish normal and faulted wheels and the accuracy reached above 90%.

Yejian Chen, Xiaolong Wang, Yong Zhang, Zongyi Xing

Detection of Squats Length Based on Axle Box Vibration Analysis

A method based on axle box vibration analysis is proposed to detect the length of squats. First, the dynamic model of wheel/rail is established for the research on relation between the frequency of track irregularity and that of axle box acceleration. Second, the basic principles of Adaptive Morphological Filtering (AMF) and Frequency Slice Wavelet Transform (FSWT) are introduced, and the slice function in FSWT is improved to advance the performance of FSWT to different signals. Finally, the measured axle box vibration signals from a metro are analyzed to estimate squats length. The results show that the method has a good engineering adaptability and feasibility.

Zhi Yang, Zongyi Xing, Jie Jiang

Profile Calibration of Dynamically Measuring Rail Wear Using LIS

Dynamically inspecting steel rail wear by the laser image system suffers from vibrations on the camera and the laser emitter, which leads to varying extrinsic camera parameters and distorted rail profile, respectively. In the paper, a novel profile calibrating method is presented to address these issues. This method involves a self-calibration of the extrinsic camera parameters, which is based on the coordinate sets projection constructed from the distorted profile to the standard one on quadruple projecting primitives including rail jaw, railhead, rail waist, and foot intersection. To remove the effect of random vibrations, we calibrate distorted profile by projecting it onto the plane x − y of the world coordinate frame. We compared our procedure with other established methods. The results show its effectiveness and superiority for dynamically measuring rail wear.

Chao Wang, Yanfu Li, Dawei Liu, Hongli Liu

Design and Implementation of Online Monitoring System of Contact System Tensioner

Tensioner is an important equipment of contact system. The real-time monitoring is carried out to running state of contact system, so as to ensure the railway system operating safely and stably. First, this paper analyzes the necessity of real-time online monitoring and summarizes the effect of environment on contact system. Second, the selection of monitoring information is introduced and monitoring terminal is designed based on the requirement of transmission and monitoring information. Third, the main function and implementation method of computer monitoring software are introduced. Finally, through installation and debugging, monitoring system can operate safely and stably and achieve alarm function so that overhaul can be guided.

Wanjiao Han, Mingguang Liu, Hui Yu

A Method of Detecting Pantograph Slide’s Abrasion Based on Image Processing

This paper presents a design of a detection method of pantograph slide’s abrasion. First, cascade filter with dynamic intensity is adopted to filter original images. The local contrast enhancement algorithm based on local standard deviation is used to enhance the target area. Next, the adaptive threshold Canny edge detection algorithm is then performed on the preprocessed images to extract the edge of slides. The slide edges are located by Hough transform, and the actual slide residual thickness can be calculated by the camera calibration method.

Saiyan Yu, Shuang Chen, Zongyi Xing

Subsystem Characteristics-Based Modeling Method for the Simulation of Electromagnetic Compatibility of Rail Transit Vehicles

Rail transit vehicles consist of subsystems and components with diverse electrical and electromagnetic characteristics, which brings difficulties to the modeling and simulation of their electromagnetic compatibility (EMC). In this paper, we proposed a modeling method for the EMC simulation of rail transit vehicles based on the subsystem characteristics. Vehicle body model, cable model, and equivalent circuit model are built and integrated for multilevel simulation of the EMC of rail transit vehicles, including body shielding effect, interior magnetic field distribution, and electromagnetic interference emission. This modeling method extracts the electrical and electromagnetic characteristics of subsystems with high accuracy and efficiency, and contributes to the practicability of EMC simulation of rail transit vehicles.

Dafa Jiang, Zhongcheng Jiang

Failure Analysis and Discussion of Bogie Temperature Sensor for Electric Multiple Unit

In order to solve the problem of delay and safety of EMU, caused by insulation decrease, temperature jump, open circuit, and structural damages of bogie temperature sensor, this paper analyzes the causes of failure, expounding the defects of traditional structure and installation method of the sensor on the bogie. By discussing two kinds of temperature monitoring methods (infrared and wireless technologies), it is shown that wireless sensor technology is usable in temperature monitoring redundancy design. The proposal of installing the emergency wireless temperature monitoring device at the point of abnormal temperature is put forward, so as to ensure that the bogie temperature is always controlled and that the punctuality and safety of the EMU are improved.

Yantong Liu, Wenjun Wang, Jintian Wang, Wanxiu Teng, Zhaoyu Ma

Study on Fault Diagnosis for Bearing Based on VMD-SVD and Extreme Learning Machine

Bearings are key components in many mechanical facilities, and the research on fault diagnosis for bearing is of great importance to the safe operation of those facilities. Thus, a method for fault diagnosis based on VMD-SVD and extreme learning machine is proposed in this paper. First, the bearing vibration signal is decomposed into a number of stationary intrinsic mode functions (IMF) by VMD method. Second, the initial feature matrix of each IMF component is decomposed by SVD, and the obtained singular value is used as the eigenvector of the signal. Finally, extreme learning machine is used as the classifier for fault diagnosis. This method’s feasibility and effectiveness have also been verified by experiment.

Qiang Zhou, Yong Qin, Zhipeng Wang, Limin Jia

Optimization of Wheel Re-profiling Strategy Based on a Statistical Wear Model

Aiming at improving the current unreasonable wheelset re-profiling schedule caused by class-lathing, this paper proposes a re-profiling strategy based on historical wear data. First, the statistical product and service solutions (SPSS) software is used to analyze the interdependency between wheel diameter wear and wheel flange thickness based on the wheel wear data of Guangzhou Metro Line 8. Second, flange thickness wear model based on state transition and wheel diameter wear model based on mathematical statistics are built, and single-stage and multistage planned turns strategies of an individual wheel are built on the two models. Finally, Monte Carlo simulation is used to compare two strategies, and the results show that multistage planned turns strategies can prolong expected life of wheels and effectively save operating cost.

Bingkui Li, Zhi Yang, Zongyi Xing, Xudong Gao

Research on Bearing Fault Diagnosis Based on Cyclic Statistics

Bearing is an important component of equipment. Different types of failures lead to different changes of the entire equipment and operating parameters. In the urban rail train operation, the quality and status of bearings have a significant impact on traffic safety. In rotary machinery fault diagnosis, second-order cycle statistics has become an important signal analysis tool. In this paper, the early fault point is realized by CUSUM combined with spectral correlation density function, and the characteristics of different fault are analyzed using second-order cyclic statistics. The research of the theory of cyclic stationary provides the direction and power for the development of bearing fault diagnosis with a case.

Dong Yan, Xiukun Wei

Research on Performance Degradation Prediction of Urban Rail Vehicle Suspension System

Along with the rapid development of urban rail transit, the security and reliability of rail transit vehicle system draw more and more attention. Suspension system plays a key role to support the car body, bogies, and wheels; therefore, it is vitally important to implement overall performance attenuation prediction, which can establish the maintenance plan based on the equipment status and reduce the cost. In this paper, a method of performance attenuation prediction about whole urban rail vehicle suspension system is proposed. The performance attenuation prediction model is established by utilizing LSSVR, of which the parameters are optimized based on SPSO. Compared with traditional methods, the SPSO-LSSVR model has higher prediction efficiency and prediction accuracy. In addition, considering the actual application, the prediction effect is analyzed when the vehicle body and bogie acceleration are model inputs, and a comparative study is carried out in the horizontal and vertical directions, which verifies the feasibility of the method used in the field engineering.

Tengteng Wang, Xiukun Wei, Limin Jia

Safe Location of High-Speed Maglev Train

This paper presented a new kind of architecture for the high-speed maglev train safe location. First, the function relationship of the operation control system of German maglev train was expounded, then the structure and function of train safe location were analyzed emphatically. Two sets of vehicle security computers were used in the new kind of safe location system architecture which were both connected with the wireless communication system, it enforced the completeness of the system structure and implemented real hot standby of the two sets of security computers, which improved the reliability of the system greatly.

Jianfeng Liu, Hongze Xu, Gegerile

Dynamic Performance Evaluation of Beijing Subway Airport Line Vehicle with Domestic Primary Suspension and Secondary Suspension

This paper introduced the method and result of Beijing subway airport line vehicle dynamic performance evaluation with domestic primary suspension and secondary suspension. Test method included test basis, test purpose, test conditions, test method, test data collection and analysis. The dynamic performance test was carried out in empty vehicle condition (AW0) with the highest speed limit as 110 km/h. The result showed that when the test vehicle ran on the straight and curve line below the highest speed limit, all dynamic indexes include wheel lateral force, and derailment coefficient and load reduction rate are within the limits specified in the specification.

Xi Li, Yuan Zhang

Analysis of Traffic Impedance Effects of Highway Rescue for Passenger Train Accidents

In the less developed areas of China, the rescue of the injured personnel in passenger train accidents mainly relies on the implementation of highways, because of the effects of adverse traffic conditions, leading to rescue traffic impedance, long rescue time, and low efficiency of rescue. This paper, taking Xinjiang of China as the example, through extracting the related characteristics of highway rescue for passenger train accidents, analyzes the influence of rescue traffic impedance and proposes the methods of reducing the time for the highway remote rescue.

Bing Wang, Xiexing Shi, Wenzhe Wang, Huiping Sun, Adila

Application of Multi-resolution State Domain Method in State Identification of Train Motor Rolling Bearings

Based on the research of motor rolling bearings of the urban rail train, we propose a kind of multi-resolution state domain (MRSD) method to identify the working condition of the rolling bearing and apply principal component analysis (PCA) method on fault classification. First, the preprocessed signal is decomposed by wavelet packet algorithm to obtain wavelet packet coefficients, and then the correlation coefficient with the original signal is calculated. On the foundation of the correlation coefficient, multi-resolution correlation entropies (MRCE) are extracted as feature parameters. Then, we utilize PCA approach to get Descartes set which represents bearing status, that MRSD, to classify the different-sourced motor bearing condition intelligently. Finally, the method is certified effectively and feasibly by the experimental result to discriminate the state of train motor bearings.

Xinan Chen, Limin Jia, Yunxiao Fu, Yong Qin

Analysis of EMUs Vehicle Body Voltage Caused by Pantograph-Catenary Off-Line Arc

Aiming at the inevitable pantograph-catenary off-line arc when electric multiple units (EMUs) run, the CRH3 EMUs, which operate at China Chongqing–Lichuan line, are selected as the research subject. Vehicle body voltage caused by the pantograph-catenary off-line arc is analyzed. First, the structure of the vehicle body and CRH3 EMUs grounding system are studied. Second, based on PSCAD/EMTDC software, electric parameters of traction network and CRH3 EMUs are ascertained, then a coupling model of vehicle-grid system is established, and an extended pantograph-catenary arc model is utilized to simulate pantograph-catenary off-line when vehicles run. Through the pantograph-catenary off-line model, vehicle body overvoltage distribution is analyzed. Finally, aiming at the CRH3 EMUs grounding system, corresponding methods are proposed to suppress vehicle body overvoltage.

Ying Wang, Fengyang Gao, Xiuqing Mu, Qiyao Li, Xiaoqiang Chen, Shiwen Liang

Safety Analysis of Train Control System Based on Colored Petri Nets and System-Theoretic Process Analysis

This paper proposes a new method called formalSTPA which combines Colored Petri Nets (CPN) and System-Theoretic Process Analysis (STPA). Using formal method to extend the STPA includes establishing the system hierarchical control structure and transforming it into CPN model. First we use ASK-CTL formula to test and verify the CPN model, and then Programming Language (ML) is used to identify the cause of hazards and realize safety analysis of system functions. ML can be used to identify hazards effectively. In this paper, the formalSTPA is applied in Chinese Train Control System Three Level (CTCS-3). The result shows that the formalSTPA is suitable for the safety analysis of CTCS-3.

Shaoqiang Hu, Daohua Wu, Huashen Wang

Research on Reliability Evaluation of Traction Power Supply Equipment Considering Human Factors

Human error is one of the important factors that affect the reliability of traction power supply equipment. However, the existing reliability evaluation methods of traction power system and equipment often neglect the influence of human factors. This paper focuses on this issue, and the task scenes are classified into three kinds: equipment status monitoring type, equipment emergent repairing type, and equipment periodic maintaining type. First, FMEA is used to qualitatively analyze the human error in each scenario. Then, the human reliability analysis methods (HRA) of three scenarios are proposed to quantify the human error probability (HEP). Finally, the example demonstrated that the proposed methods can quantify the probability of HEP and characterize the influence of human error on the reliability of traction power supply equipment.

Qianqian Yang, Sheng Lin, Ding Feng

Bayesian Network-Based Reliability Analysis of High-Speed Train Bogie System

The events in the fault tree of CRH2 high-speed train bogie system are regarded as nodes in Bayesian network (BN) based on the relationship between the fault tree and the BN. The bogie system is simulated based on BN with improved expectation maximization algorithm (EM). The weakness of the bogie system can be found through the calculation of the fault probability and the causation analysis. It provides the theoretical basis for drawing up the maintenance project and troubleshooting the system, and helps to make the maintenance decision.

Shuting Zheng, Yong Qin, Li Wang, Limin Jia, Jinchu Zheng

A Rail Corrugation Detection Method Based on Wavelet Packet Energy Entropy

Aiming at the problem of the rail corrugation detection about low efficiency and low success rate, a method based on wavelet packet energy entropy (WP-EE) was proposed. First, the rail corrugation and the train physical fitting models were established, and then a coupling dynamics model was developed by using SIMAPCK. Next, four-layer wavelet packet decomposition of the axle box vibration signal is performed, wavelet pocket energy entropy and wavelet energy of each node are calculated. Finally, the simulation results were compared which reflect the information of rail corrugation.

Kuan Lang, Zongyi Xing, Wei Dong, Xudong Gao

Pantograph Slide Plate Abrasion Detection Based on Deep Learning Network

As the key components of electrified railway power supply, pantograph has complex electrical and mechanical effects while working, resulting in a high fault ratio. It is important to detect the defects timely to guarantee the safety of the railway system. Manual detection is the most common detection at present, which is high in accuracy but low in efficiency. Another automatic detection system is limited in function or poor in accuracy. In this paper, deep learning method is used for defects recognition of pantograph slide plate to the identification and classification of different types of defects. Through a large number of experiments and parameters optimizing, the innovated proposed in this paper can reach an accuracy rate of 90.625% used to identify a variety of different defects. This provides an alternative for pantograph slide plate defect identification.

Yan Li, Xiukun Wei

Track Surface Defect Detection Based on Image Processing

In this paper, computer vision-based methods are presented to detect the rail track surface defects automatically. The detection is the key foundation to inspect and assess railways, and for the operation safety and rail maintenance, railways inspection is the critical task. To achieve this goal, the rail surface edge’s likelihood is investigated, and the Canny edge detector for defects extraction is introduced to guarantee the detection of the rail surface damage accurately. The analysis performed on some image data captured on the field has demonstrated encouraging detection performance on rail track surface defect detection.

Yuxin Liu, Xiukun Wei

A Hybrid Temporal-Spatio Fusion Algorithm for Moving Pedestrian Detection in Traffic Scenes

To accurately extract traffic information, the pedestrian detection algorithm of combining time domain, edge and internal–external marker information is proposed. First, a rough motion mask is extracted based on the temporal change of adjacent multi-frames and Canny edge detection, which effectively solves D-value localization and noise problem. Second, to improve the accuracy of airspace segmentation and eliminate over-segmentation, spatial mask image is received by introducing the technology of quadratic reconstruction, internal–external marker, and watershed transformation. Finally, an accurate pedestrian detection mask is obtained by integrating the rough mask and spatial mask image. The experiment results using Beijing South Station video show that this method can detect the complete target information and obtain the better pedestrian detection results in dynamic traffic scene.

Aili Wang, Yuanyun Sun

Research of Online Nondestructive Monitoring of Composite Components Using FBG

Fiber Bragg grating (FBG) is a new type of passive fiber optic device. It has been mainly used for the health monitoring of large structures such as bridges and buildings, while the application of the online nondestructive monitoring of composite components is less. This paper introduced the composite nondestructive testing method, fiber grating sensor application at home and abroad, as well as FBG sensing principle. Then simulation was performed for 3D model of carbon fiber levitation chassis frame of maglev vehicle under the normal operating condition and extraordinary operation condition. Moreover, the layout design of FBG sensors on the surface of carbon fiber levitation chassis frame was performed using the strain distribution, and then FBG sensing network and its monitoring system were designed. The preliminary design results showed that the online nondestructive monitoring system can meet the requirements of engineering measurement of carbon fiber levitation chassis frame.

Xianfeng Wang, Zhongcheng Jiang, Xiaobo Liu, Jixiong Jiang

Study on the Adhesion Optimization Control Strategy and Its Application Based on Trend Forecasting

Wheel–rail adhesion is a complex question which is quite easily interrupted by external time-varying signal. Furthermore, the maximum adhesion point is time variant. It is difficult to find the maximum adhesion point for adhesion control procedure. This paper gives a deeply analysis on wheel–rail adhesion mechanism and then proposes an adhesion optimization strategy based on trend forecasting. This strategy is robust which is not sensitive to external environment, but mainly related to train’s operation condition. For validating its feasibility and reliability, the traction performance test in wet rail condition of HXD1 electric locomotive before and after adhesion program optimized is preceded. The test results indicate that the adhesion strategy proposed in this paper is useful to search the maximum adhesion point and improve the traction ability. It also indicates that this strategy is right and robust.

Yunxin Fan, Biao Ye, Zhongcheng Jiang, Jixiong Jiang

Fault Identification for High-Speed Vehicle Suspension System Using Nonlinear Filtering

Suspension system is vital important to safe operation of the high-speed vehicle. Parameter estimation is a new way for fault identification of suspension system by monitoring parameter attenuation and sudden failure of key components. A lateral dynamic model is built in this paper, based on which a nonlinear filtering algorithm called Rao-Blackwellized Particle Filter (RBPF) is applied for parameter estimation. Furthermore, RBPF based on repeat-uniform-sampling strategy is proposed for avoiding impoverishment of parameter particles, and fault identification of sudden failure is realized. Simulation results show that algorithms proposed and studied in this paper are effective and reliable with high accuracy.

Xiaozhong Zhang, Xiukun Wei, Limin Jia

Research on Gearbox Fault Isolation Based on VPMCD

As a power transmission device, gearbox is an indispensable component of the urban rail vehicle, and it is significant to determine the fault type of the gearbox and to provide the basis for the maintenance and maintenance plan of gearbox. In this paper, traditional VPMCD method is improved in the selection of the prediction variables and the parameter estimation, and based on the error between the estimated value and the actual value, the fault type of the gearbox can be accurately judged. The applicability of VPMCD is analyzed by an example, and compared with other methods, the superiority of the optimized VPMCD is verified.

Xiukun Wei, Dong Yan

A Feature Extraction Method of Rolling Bearing Fault Signal Based on the Singular Spectrum Analysis and Linear Autoregressive Model

A feature extraction method of rolling bearing fault signal based on the singular spectrum analysis (SSA) and linear autoregressive (AR) model is proposed. The SSA is used to achieve the noise reduction, which has three steps: decompose original signal into multiple components, remove the components which have smaller contribution, and reconstruct the signal. Then, the reconstructed signal is modeled by the linear AR model, and the coefficients of the model are extracted as the characteristics of the signal. Finally, the proposed method is verified by using the experimental data of Case Western Reverse Lab.

Kun Xu, Gui Wang, Zongyi Xing

Passenger Flow Assignment of Evacuation Path in the Station Based on Time Reliability

In order to realize the reasonable assignment of passenger flow on the evacuation route. Only considering the evacuation time cannot effectively assign the passengers. The path with the shortest theoretical time does not have the highest time reliability. Put forward the measurement of evacuation time reliability. Then, the path impedance function is constructed under the condition of the comprehensive evacuation time reliability and the evacuation time under the congested condition. Combining with the Wardrop equilibrium theory and establish the user equilibrium model based on the evacuation time and time reliability. A method of successive averages (MSA) is used for solving the route assignment result. Finally, the Fuxingmen station is used to verify the validity of the model.

Chunwei Sun, Jie Xu, Limin Jia, Yong Qin, Kunsheng Zhan, Jian Zhang

Simulation of Aging Characteristics of Power Switch Device Based on Saber

IGBT is a power switch device that is very important in modern power electronics. The reliability of IGBT concerns the security of circuits and even the whole system, while IGBT module’s aging is inevitable, so it is necessary to study the aging of IGBT module. At home and abroad, the measurement of the electrical parameters when the bonding wires fall off is used to identify the aging failure state of IGBT, but the consideration is far from comprehensive, the evaluation is also inaccurate. This paper uses the saturation voltage drop which is easy to measure as a state characteristic parameter and considers the influence of junction temperature and collector current to the saturation voltage and IGBT module’s aging failure to evaluate the aging failure of IGBT module.

Yujia Guo, Mengzhu Wang, Lei Wang, Ruichang Qiu, Guofu Chen

Evaluation of Emergency Evacuation Capacity of Subway Station Based on M/G/c/c

In the case of an emergency, accurately assessment of evacuation capability is the key to safe and efficient evacuation. M/G/c/c represents a queuing model where customers’ arrivals obey Poisson distribution, the service time obeys general distribution, the system has c service desks, and its capacity is c. It is suitable for the analysis of pedestrian walking process and the calculation of corresponding indicators in various spaces. The evacuation time, passenger flow density and facility bottleneck are chosen as evaluation indexes to analyze pedestrian walking characteristics and connection structure of station divergence nodes. Based on the M/G/c/c queuing model, a pedestrian divergence node probabilistic selection optimization model is constructed. Then, we use lingo software to solve the model. And Jianguomen Subway Station is used to verify its effectiveness.

Yacui He, Jie Xu, Limin Jia, Yong Qin, Kunsheng Zhan, Jian Zhang

Research on the Abrasion Detection Technology of the Pantograph Slipper of Urban Rail Train

In order to realize the online noncontact detection of the Abrasion of the Pantograph Slipper of Urban Rail Train, the abrasion detection technology of pantograph slipper of urban rail train is studied. In this paper, an abrasion detection method of pantograph slipper of urban rail train based on image processing is proposed, and the steps are as follows: First, the mixed noise of the original image from the acquisition system is filtered by image filtering. Then, the edge of Pantograph Slipper in the image is detected by the adaptive Canny edge detection based on histogram concavity analysis after image filter. Finally, the abrasion curve of the Pantograph Slipper is obtained by camera calibration and curve blending, and which is used to judge whether the abrasion of the pantograph slipper is transfinite. The results of the experiment showed that the proposed method is effective to detect the pantograph slipper abrasion curve in the original image. The proposed method is effective to realize the online non-contact detection of the Abrasion of the Pantograph Slipper of Urban Rail Train.

Xuebing Hu, Yejian Chen, Yong Zhang, Zongyi Xing

Research on Fault Diagnosis of Vehicle Equipment for High-speed Railway Based on Case-Based Reasoning

Vehicle equipment plays an important role in high-speed railway train control system for safety protection and efficiency improving. The role of vehicle equipment for high-speed railway can be affected by a number of uncertain faults and these faults have characteristics of diversity, concealment, and overlap. To solve the above problems, this paper proposes a new algorithm to detect faults of vehicle equipment based on Case-based Reasoning. A database is created based on previous successful cases and features of these cases are extracted. Then fault causes of vehicle equipment are derived by matching the information of target cases to cases in the database. Then maintenance suggestions are given according to fault causes of vehicle equipment. The test result shows that the algorithm can diagnose faults of vehicle equipment for high-speed railway accurately and effectively.

Lixuan Chen, Dongxiu Ou, Hongjing Yao

A Bayesian-MCMC Model to Assess Metro Train Collector Shoes Slider Degradation Under Different Materials

This paper presents a Bayesian-MCMC model to assess collector shoes slider degradation under different materials. A Markov Chain Monte Carlo (MCMC) method, based on the Bayesian decision model, is put forward and built up a framework in case of the life cycle of collector shoes under different materials forecast. All of inspection data is gathered from Beijing metro lines, and WinBUGS software are used to predict the slider’s wear rate. Result shows that the difference between the predicted value and the real one is less than 10% of the later one. Consequently, in case of new metro equipment parts, the newest method is able to ensure the safety operation in the metro by providing a valid device to the equipment manufacturers, the maintenance department as well as the purchasing department of the metro equipment.

Yue Pan, Guoqiang Cai, Xi Li

Design of High Power Factor Charger for Transportation Electrification

The electrification of transportation equipment have a high impact on the power grid, especially when the electric energy is used as its power source, the power conversion of the charging equipment will produce a large amount of harmonics. In order to reduce harmonics and improve operating power factor of the charging system, we select a specific circuit topology based on analysis of the operating characteristics of this type of charger, and carry out theoretical analysis and simulation verification. On these foundations, the prototype of charger is made and closed-loop debugging is carried out, the experimental results show that the output voltage of the prototype is adjustable, the grid-side current is undistorted, and realized a unit power factor operation.

Fucun Li, Liang Guo, Hao Li, Guodong Qu

Comparative Study of Fault Detection Algorithm Based on Multivariate Statistical Analysis

This paper has studied several methods based on multivariate statistical analysis, DPCA, CPCA, and MBPLS, which are all the extension of PCA, mainly introducing the principles and steps. At the same time, a method for determining the threshold in practice is proposed in this paper. Besides, we verify the effectiveness of the detection method by the data of train suspension system from simulation experiment. And then we make a comparative analysis of the results through the effect and time. According to the results, we can find it is obvious that CPCA and MBPLS are superior to DPCA in detecting faults.

Shuyu Zhang

Research on Cycling Energy Saving Based on Improved Violence Search

Aiming at the energy-saving optimization problem of metro train, this paper presents a new energy-saving research method based on improved violence search method. First, the dynamic model and the motion equation of single train are analyzed, and the model is applied to the timing energy-saving model which is closest to the real situation. Second, the paper analyzes the multiple constraints of single-train running and puts forward the goal of three single-train runnings. Finally, an improved violence search method combining constraint method and violent search method is used to solve the multi-objective problem. Based on the violent search method, this paper transforms the multi-objective problem into the single-objective problem through the target constraint method, and then solves the single-objective problem through the violent search method to make higher solution speed of multi-objective optimization problems. After applying the method, the “speed–distance” and the “power–distance” curves are simulated and calculated with the actual line data of Beijing–Yizhuang Line Rong Jing East Street to Wanyuan Street as input.

Liangliu Bai, Yong Zhang, Zongyi Xing, Xinrong Liu, Xuejin Wang

Analysis of Running Stability of High-Power Locomotive Under Harmonic Wear Wheel

Harmonic wear is one of the most common forms of out-of-round wheel (OOR), especially in heavy locomotives, potentially affecting the running stability. In this paper, a locomotive wheel-rail interaction coupled dynamic model was established for numerical simulation, and common harmonic wear types of locomotive wheels were employed as excitations of the dynamic model. Then, accelerations and Sperling indices of the locomotive in different harmonic wear types were calculated and compared. The result shows that harmonic order has a great influence on locomotive lateral vibration, and has a little effect on the vertical vibration in the same harmonic wave depth; harmonic wave depths have a larger effect on the lateral and vertical Sperling indices in the same harmonic order; compared with no harmonic wear, the lateral stability in different harmonic wear types will change obviously while the vertical stability will not change significantly.

Qian Xiao, Zhixiang Luo, Jifeng Zheng

Detection of Wheel Tread Wear Based on Laser Displacement Sensor

In order to solve the problems of heavy workload and low accuracy existing in manual measurement, a method based on laser displacement sensor (LDS) is proposed to detect wheel tread wear. First, the 2D laser displacement sensors installed on the lateral side of the track are used to collect the wheel tread data. Then, techniques including data preprocessing, coordinate transformation, data fusion, and so on are applied to process the wheel tread data combined with standard wheel tread data. Finally, the wheel tread wear can be calculated by using geometric relationship. Error analysis and field experiments show that the accuracy of the proposed method is less than 0.2 mm and has the strong anti-interference ability. The proposed method can greatly meet the actual requirements of measurement of wheel tread wear.

Jianyu Zhang, Zhi Yang, Yong Zhang, Zongyi Xing

A Hybrid Filtering Algorithm for Pantograph Image Denoising

In the pantograph image detection method, the pantograph image is affected by electromagnetic interference and transmission medium, so there are some noises in the image, which are mainly the gauss noise and impulse noise. For the pantograph image denoising problem, the single denoising method is not effective. Generally, two types of filters are used to filter the noise step by step. In this paper, a hybrid noise filtering algorithm is proposed. First, ABDND-based median filtering algorithm is used to suppress the impulse noise. Then, an improved mean filtering algorithm is used to suppress the Gaussian noise. Two algorithms are used to filter out the hybrid noise in the pantograph image. Finally, the experimental results show that the proposed hybrid filtering algorithm can effectively remove the noise and protect the edge of the image, which is superior to the traditional filtering algorithm.

Weiwei Pei, Zongyi Xing, Zhuang Chen

An Effective Railway Dynamic Invader Detection and Tracking Method

In this paper, an effective railway dynamic invader detection and tracking method is proposed, which can be used to detect and track dynamic invader that appears in the vicinity of the railway track. Generally, this method can be divided into three stages, namely, intrusion region division, object detection, and invader tracking. In the first stage, we propose a novel algorithm, combining morphological processing and progressive probabilistic Hough transform, to extract the railway track, and a set of structure elements are designed to enhance the extraction effect. Based on the result of extraction, the intrusion region, the vicinity of the railway track can be divided to reduce the amount of computation later. In the second stage, we adopt visual background extractor to detect the object. And in the last stage, Kernelized correlation filters is used to track the invader, the object in the intrusion region. The results of the experiment based on actual railway scene show that the method this paper presents has excellent performance.

Qun Wang, Xiaofeng Li, Limin Jia

Fault Diagnosis and Countermeasure for the Pantograph Automatic Lowering Under the Condition of Dual-Locomotive Running

A pantograph automatic lowering fault that occurred during dual-locomotive running was discussed, and signal interruption was found to be the direct reason. According to the theory of transmission lines, and combining with the freight environments, particularly, the connecting method of locomotives, this paper points out that the poor contact in the equipment of Wire Train Bus (WTB) was the root cause. Through the theoretical research and field investigation, the major factors that might cause a similar fault were researched, and the fault phenomenon was explained comprehensively. It also provides important reference value for improving WTB’s reliability and reducing the possibility of pantograph automatic lowering.

Xiao Feng Zhong, De Chang Liu, Ping Luo, Hai Yi Zhou

Simulation and Scheme Study on Braking Process of Urban Rail Transit

In this paper, through the design of train braking process algorithm based on traction calculation, we compiled the Matlab program to realize the simulation of train braking process, studied the train braking of urban rail system and relevant problems, and set different calculation conditions for line and train, and carried out several simulation examples. The results can be used for analysis of train traction, braking speed, train mass, and other factors on the braking capacity of the train, and can also provide reference for the related engineers in the design and operation of the subway.

Xian Zhang, Yanhui Wang, Boyan Hao

Study of the Destruction Resistance of Urban Rail Network Based on Random and Intentional Attack

In complex environments, urban rail transit stations are susceptible to various factors that cause station function loss. Therefore, how to evaluate and quantify the key nodes in the network and solve the fluctuation of the whole network capacity under the intentional and random attacks has become an important issue. In this paper, the method of evaluating important nodes is defined according to the complex network index, and the efficiency of the road network under different attack rules is solved. According to the experimental results, the Beijing railway network was evaluated. It was found that the urban rail network had strong resistance under single-point attack, and it was very vulnerable under coordinated attack.

Boyan Hao, Yanhui Wang, Xian Zhang, Huiru Zhang

Method of Health State Assessment for Satellite Power System Based on Fuzzy Judgment and Variable Weight Layered Evaluation

In order to improve the reliability and safety of satellite power system, the concept of health management is introduced to the research of health state assessment about satellite power supply. Considering the complex characteristics of satellite power system, a health state assessment method based on fuzzy judgment and variable weight layered evaluation is proposed and applied to the assessment of satellite power system. First, the fuzzy comprehensive evaluation method is used to quantify the influence degree of fault modes on the system and obtain the objective corresponding health degree. The method also combines analytic hierarchy process (AHP) with variable weight synthesis to solve variable weights and calculate health degree of the system step by step, which conducts real-time health state assessment for satellite power system. And then, the calculation results are divided into healthy, good, attentive, deteriorative, and morbid 5 levels to characterize the health states of the evaluation object. Finally, the applicability and validity of the method are verified by the concrete calculation example.

Pei Zhen Wang, Lei Wang, Ruichang Qiu, Lijun Diao, Yujia Guo

Intrusion Detection for High-Speed Railway Perimeter Obstacle

Perimeter intrusion detection is one of the most important conditions for high-speed railway safety. The research and application of perimeter intrusion detection are first introduced, including an infrared detector, pulse electronic fence, vibration cable/fiber optic cable, intelligent video analysis, etc. Then, we analyze the application of video surveillance in perimeter intrusion detection, point out the difficulties of video surveillance for the day- and nighttime, and summarize the popular methods of the intruding object recognition and the intruding behavior analysis. Finally, we put forward the future research direction of perimeter intrusion detection for high-speed railway.

Qinghong Liu, Yong Qin, Zhengyu Xie, Tangwen Yang, Gaoyun An

Research into Thermal Response Time Fault Diagnosis of Temperature Sensor in High-Speed EMU

High-speed EMU temperature sensors are used to detect important parameters such as temperature on the train. The thermal response time of the temperature sensor is the main factor affecting the temperature measurement. The failure of the thermal response time will lead to the failure or false positives of the vehicle temperature sensor, which will cause the speed limit and stop, which will seriously affect the railway operation order. This paper focuses on the thermal response time of the temperature sensor of the high-speed EMU and analyzes the dissection and simulation of the temperature sensor. The results show that the reason for the failure of the thermal response time is that the sensor probe into the air leads to the thermal resistance becomes larger, reduces the heat transfer speed, and finally makes the thermal response time longer. Finally, according to the diagnostic analysis, results put forward the corresponding measures.

Xuguang Lin, Wenjun Wang, Bin Li, Jianwei Miao, Yantong Liu

Super-Gaussian Random Vibration Test Inductive Method Based on Measured Data

Toward the situation that the traditional inductive method is not suitable for super-Gaussian data, this paper presents an inductive method of super-Gaussian vibration data of locomotive equipment according to the actual measured data of Lanxin line and the actual operation situation. By verifying the measured vibration data, it is found that the data shows a steady random supergrid characteristic. The test conditions of body installation equipment of locomotive under super-Gaussian random vibration are put forward by analyzing the inductive values and the kurtosis value, which solves the problem of using the measured vibration data to compute the simulation conditions of the super-Gaussian random vibration environment.

Peng Wang, Hua Deng, Liuqing Xiao, Guotao Liu

RAM Assessment of CTCS-1 ATP Based on Enhanced Bayesian Network

China Railway Corporation proposes the upgrading and updating plan of general speed train (train running speed under 160 km/h) to improve the outdated status of general speed railway. The new CTCS-1 Automatic Train Protection (ATP) system will be safer, more reliable and advanced than the existing train control system. In this paper, enhanced Bayesian Network (BN) is first used in CTCS-1 ATP RAM assessment, which is mainly used to analyze the structure of two different ATPs and establish the corresponding enhanced BN models. Finally, the Reliability, Availability, and Maintainability (RAM) of these two different ATPs are obtained and analyzed through enhanced BN simulation model. The assessment results show that the RAM indicators of CTCS-1 modular redundancy ATP and system redundancy ATP can satisfy the requirements of Chinese train control system requirement specifications, but the RAM indicators of CTCS-1 modular redundancy ATP are better than CTCS-1 system redundancy ATP.

Yue Xu, Zhongtian Liu

A Novel Online Measuring System for Wheel Size Based on Laser Displacement Method

A new wheel size online detection system for subway vehicle based on laser displacement method is introduced to solve problems such as large workload and low accuracy of manual measurement for metro wheelset. This paper describes the system structure, proposes the design of hardware and software, and expounds the principle of using laser displacement sensor to realize the measurement of the thickness of wheel flange, height of wheel flange, and wheel diameter parameters. In order to verify the usability of the system, the field round test and the vehicle test are carried out, and the measurement results between the online system and workman are compared. The results show that the detection system has the advantages of accurate measurement and good consistency, and can replace the existing manual measurement to meet the requirements of wheel size measurement.

Yong Zhang, Changgeng Wang

Sub-problems Interaction Analysis-Based Three-Level Decomposition Algorithm for Real-Time Train Scheduling and Routing Problems in Railway Stations

The management of rail traffic in stations requires careful scheduling to fit to the existing infrastructure, while avoiding conflicts between large numbers of trains and satisfying safety or business policy and objectives. The train scheduling and routing problem studied includes four tasks: scheduling, routing, platforming and conflict resolution. We propose a three-level decomposition method based on the interactional relationship among four tasks mentioned above to enhance the computational efficiency. This method is tested on full-day timetable obtained from a real-world station.

Lijie Bai, Thomas Bourdeaud’huy, Emmanuel Castelain, Qi Zhang, Ziyuan Liu

Train Operation Intervals Optimization Based on a Group Dynamics Model

Train operation interval is a most important parameter in the railway management work and train dispatching work. It also determines the capacity of the railway sections. In this paper, a train interval optimization model based on group dynamics theory is proposed. It takes the potential energy of the artificial potential field as the optimization object, which is defined with the train operation interval. And the train operation rules, especially the intervals between arrivals and departures, are designed as the constraints of the model. An immune clone algorithm is designed to solve the model. A computing case is presented, and we got the optimal intervals of trains on the timetable. The computing case proves the effectiveness of the approach. This paper presents a new method to design train intervals for timetable designers and dispatchers.

Xuelei Meng, Bin Zhang, Limin Jia

Study on Energy Saving of Multi-vehicle Operation Based on Genetic Optimization Algorithm

Aiming at the multi-vehicle energy-saving problem of a metro train, this paper presents a research method of multi-vehicle operation energy saving based on genetic algorithm. First, the process of braking energy transfer in multi-train operation is analyzed. Second, taking the least energy consumption, and travel time as the targets, all-day trains, and the high/low peak traffic as the constraints, a multi-vehicle energy-saving model based on a multi-vehicle operation energy saving is established. Finally, the genetic algorithm is used to obtain the optimal stopping time and starting interval, and the total energy consumption, train energy consumption, and line loss are calculated. At the same time, the multi-vehicle energy-saving simulation is carried out by using the short-term of four sections of Rong Jingdong Street Station to Yizhuang Bridge Station of Beijing Yizhuang Line, and it also optimized the stopping time and the starting interval.

Xuejin Wang, Xiangxiang Zhou, Yong Zhang, Zongyi Xing

A Simulation Research for Fare Collection Equipments on Tiyuchang Station in Xi’an Subway

The Automatic Fare Collection (AFC) system is a kind of infrastructures for urban rail transit and is widely used in the subway system around the world. It is an important problem to determine the setting number of AFC equipments. While setting too little equipments, there will be congestion and may cause security problem. And setting too many will bring waste. This paper uses simulation method to study this problem for Tiyuchang station of Xi’an subway. It uses its own queuing simulation software for AFC equipments to analyze the passenger data of Tiyuchang station and gives suggestion based on simulation results.

Guang Li, Chaosheng Wu

An Integer Programming Model of Reinvestment Strategy Based Project Portfolio Selection and Scheduling with Constrained Resource

Selecting an appropriate series of projects among numerous candidates and assigning start and finish time for every selected project under the constraints of limited resource does matter in the project management. With the introduction of annual budget and time value of capital, the proposed problem becomes more complex. In this paper, an integer programming model is proposed and constructed to model the situation of selecting and scheduling suitable project portfolio at the same time with constrained resource, in which reinvestment strategy is also applied in the process. In reality, annual budget is time-dependent, so it is necessary to take time value of capital into account during the modeling process. The use of reinvestment strategy means that the profit earned by accomplished projects is put into the resource pool to finance more projects to be selected and executed in order to make the total profit of project portfolio maximal. During the modeling progress, others constraints are also considered, like project interrelationship, to represent closely practical situations.

Baolong Wang

Track Assignment Adjustment Problem in Complex Railway Passenger Stations

Track assignment plans are often adjusted for the purpose of safety and the minimum delay in real-time conditions, especially in busy complex railway passenger stations. First, taken trains as nodes, tracks as colors, a graph coloring model is designed with the objective function of the minimum total weighting delay. Then, a heuristics algorithm based on the two-stage solution method is put forward. Finally, a simple case is used to demonstrate the effectiveness and high efficiency of the proposed methodology based on graph coloring theory about how to solve the track assignment adjustment problem.

Yinggui Zhang, Min An, Li Wang

Study on Dynamic Characteristics of Metro Stray Current Based on CDEGS

In this paper, a stray current dynamic distribution model was established by Current Distribution, Electromagnetic Field, Grounding and Soil Structure Analysis (CDEGS) software. The rectangle cut-and-cover model is based on a practical construction in Shijiazhuang Metro Line 3. It showed the dynamic distribution of conductor-to-earth voltage and stray current under constant-current-strategy condition and target-speed-strategy condition. The traction current of the former one is changeless, but the later one should take into account passenger comfort and operational efficiency. The simulation results give several conclusions: Traction operation strategy and locomotive position have great impacts on the distribution of voltage and current. Through the analysis of various parameters, some efficient measures can be used to avoid the overvoltage condition and serious metal corrosion.

Mingjie Liu, Sheng Lin, Liping Zhao, Xiaohong Lin, Liang Chen

Analysis of Influencing Factors of Energy Saving and Emission Reduction for Railway Transportation of China

The current status of energy saving and environment protection in railway sector is analyzed in this paper. The passenger transport-related energy consumption has degraded dramatically, and the freight-related energy consumption on the decline in general, but the energy consumption per unit grows slightly in last two years, due to the shrinking of rail freight volume. Then, the key effective factors of energy saving and environment protection are presented from the aspects of key facilities and equipment and operation management. Finally, based on the development status of China railway, some new technologies and measures of energy saving and environment protection in four perspectives are proposed, such as life cycle management of railway system, lightweight cabin design and manufacture, comprehensive energy consumption control and energy recycle, and high-efficiency operation.

Liang Sun, Huiting Guo, Li Wang, Liang Chen, Jianhua Chen, Mei Liu, Wei Bao

Study on the Method of Passenger Transport Organization in Peak-Hour of Railway Station

In recent years, the passenger capacity of the railway continues to soar, increasing the pressure of passenger transport organizations. Although many stations would increase passenger capacity by building a new equipment and facilities, the effect is still not satisfactory, if the new technology and equipment can be applied at the same time, and we give full consideration to the characteristics of passenger flow, concern about improving passenger transport efficiency, then the passenger capacity can be enlarged greatly. This essay aims to find out take effective organizational methods to disperse the streamline of people to avoid the peak-hour crowding and introduces the concept of the peak-hour crowding, and passenger flow characteristics. And then, the passenger streamline organization and passenger capacity of equipment were discussed and studied. It focuses on the composition of passenger and characteristics of peak-hour crowding in domestic railway station. And analyze how to computing station equipment capacity, the way to optimize the management of passenger streamline in peak-hour.

Yuyang Nie, Xiaoning Zhu

Bayesian Network Inference on Departure Time Choice Behavior

Departure time choice behavior plays an important role in travel decision for metro passengers during morning peak hours. Different from statistical models, this paper proposed Bayesian networks (BNs) to model the departure time choices of metro passengers. The structure of BNs is learned through K2 algorithm and its parameters are estimated by maximum likelihood estimation (MLE) method using the stated preference (SP) survey data. Main results are obtained as follows: (1) passengers can accept departure earlier than usual in the range of 0–20 min; (2) passengers will prefer to choose departure earlier if they enjoy a 20% or more discount on metro fare; and (3) passengers are willing to departure at usual time with slight crowding while they prefer to departure earlier under serious crowding. These findings contribute to making strategies for passenger flow control and safety operation for metro stations.

Xian Li, Haiying Li, Linqiao Qin, Xinyue Xu

Metro Station Facility Layout Optimization Model Based on the Level of Service Reliability

Facility layout in metro stations is closely related to the facility utilization, level of service (LOS), and even the pedestrian safety. Aiming at this problem, the concept of reliability is incorporated, and followed by the definition of LOS reliability of single facility, single streamline, and whole station. Among these, pedestrian flow arrival characteristic and facility heterogeneity are considered. Then a facility layout optimization model based on the LOS reliability is proposed, and the decision tree cycle algorithm combining simulation is used to solve the problem. Finally, a case study of Zhichunlu Station in Beijing metro is presented to validate the effectiveness of the proposed model. Compared with reality, the optimization scheme can improve the performance of the station significantly including its operation efficiency and security.

Qingwen Jia, Jianrui Miao, Xu Chen

Monte Carlo Simulation Method Used in Reliability Evaluation of Railway Overhead Contact Line

This paper presents an application of Monte Carlo Simulation method for reliability evaluation of the railway overhead contact line system by establishing a repairable system model with four components placed in series. Weibull distribution is adopted to characterize the failure rate of system component. Multinomial distribution is adopted to characterize the occurrence probability of different failure mode of system component. The parameters of probability distribution are obtained from failure data collected in the maintenance of actual overhead contact line system. The system reliability indices are calculated by Monte Carlo simulation method. The simulation result is acceptable compared to the result obtained from Markov analysis method.

Jianfeng Xu, Yuan Zhong, Shibin Gao

Optimization Study on Operation Plan of Intercity Trains Based on Minimization of Total Social Cost in Intercity Passenger Corridor

By taking operating cost and transportation external cost into consideration, a bi-level programming model is established, with which the upper level aims at the minimum social cost and the lower level is modeled by traffic flow assignment in intercity passenger corridor. A Simulated Annealing (SA) algorithm is used in the solution of the bi-level model to figure out sharing rate of all kinds of transportation modes and operating plans of trains. With an example in the end, this paper contrasts and analyzes the variation trend of the minimum total social cost under different operating frequencies of intercity trains to conduct a sensitivity analysis on the operating plan.

Yu-ling Ye, Yun-fei Zhou, Lu-qi Yang

High-Speed Railway Timetable Rescheduling Method: A Bi-level Integrated Programming Approach

China’s railway has experienced a large-scale development in the recent years. Making up for delay time considering the energy efficiency when the train is delayed, which can satisfy the travel demand for passengers and save rail energy costs at the same time, will become the focus of future research on the railway. A bi-level programming optimization model is proposed in this paper. In the upper layer, the high-speed railway timetable is adjusted under unexpected interferences, and then the energy saving is optimized in the lower layer. A real-world case study is presented to illustrate the validity of the model and algorithm.

Huiru Zhang, Limin Jia, Li Wang, Yong Qin, Min An

Characteristic Analysis of High-Speed Railway Network in China

The high-speed railway has been developed rapidly, and the topological structure and transportation organization of the railway network have changed greatly. In this paper, China’s high-speed railway is taken as the research object and train flow network is established. Indexes are calculated from the perspective of the network and transportation organization. The comprehensive evaluation index is determined with TOPSIS method to identify key indicators of the station. The example identifies not only the provincial capital stations, but also the stations with small scale but critical position affecting the whole network transportation service capacity. The research of high-speed railway network property contributes to forming the transport organization strategy, which makes the network service feature more robust and helps for the optimization of railway network infrastructure.

Dan Guo, Yong Qin, Li Wang, Min An

Coordination of Transport Organization and Building Maintenance for Jixi Marshalling Station

The coordination of transport organization and building maintenance is an important method by which to improve the efficiency of marshalling yard building maintenance. This study takes Jixi station as an example, and analyzes currently existing problems affecting building maintenance. It proposes a coordinated approach to the maintenance of buildings and the organization of marshalling station transportation. It uses network planning methods to analyze the shortest or longest times that and construction and reparation tasks require. Traffic data are analysed in order to determine the methods for the maintenance schedule of a building’s skylights. A coordinated approach to the original station Jixi weekly skylight plan is proposed in order to optimize coordination, and ultimately to reduce the impact of construction on the repair work of marshalling station.

Jianxiang Li, Xiaoning Zhu

A Method to Forecast and Estimate Traffic Demand of Airport Moving Sidewalk

Large airports have the problem of long passengers’ walking distance. In order to enhance the level of service and ensure passengers’ experience, developing airport automated people mover (APM) system and moving sidewalk systems are the important ways to solve the problem of inter-traffic in large terminals. Moving sidewalk is often used within a terminal while APM system is often used between two terminals or among all terminals. This paper proposes a method to forecast and estimate traffic demand which is suitable for airport moving sidewalk system based on the traditional four-step method. Experimental results prove that the proposed method is reasonable and effective.

Yuchun Ren, Xiaoning Zhu

Dynamic Multi-objective Optimization Problem of Container Intermodal Transport: An Empirical Analysis on the Belt and Road Initiative of China

The Belt and Road Initiative of China proposes a higher request for the development of container intermodal transport. The traditional intermodal transport organization mode may change: the daily handling capacity of container railway central terminal will increase, speed of train will improve, there will be more and more double-stack container train come into use. These changes will have far-reaching consequences on the container multimodal transport development of China. This paper attempts to evaluate the economic and environmental effect on the potential change of container intermodal transport of China on the Belt and Road Initiative, with a specific focus on energy consumption and emission. Multi-objective optimization model is built to minimize transport time, cost, energy consumption, and also emissions, which is based on simulation model of locomotive, Non-Dominated Sorting Genetic Algorithm II (NSGA-II) is used to solve the multi-objective optimization model. An empirical case regarding container intermodal transport from Shanghai to Urumqi is applied to verify the validity of model in the end. The dynamic multi-objective optimization model allows the logistics enterprise to be more flexible in their decision to plan the scheme of container intermodal transport.

Jue Hou

The Impact of Carbon Abatement Policies on Port Intermodal Freight Transportation Routing and Cost

The rapid development of port intermodal freight transportation indicates the high demand for door-to-door transportation services. Satisfying such demand would bring high profits to logistics industry as well as produce great amounts of greenhouse gas emissions. The latter phenomenon is becoming the main threat to our environment. This paper developed an integrated optimization model to solve the intermodal transport routing problem. Furthermore, in order to investigate the effect of the carbon abatement policies (i.e., carbon tax and carbon credit) on optimal route, transportation cost, and carbon emissions, we adapted the original model by, respectively, considering each of the policies. Based on the illustrative example, the result shows that the carbon tax policy does not make an obvious influence on the optimal route with total and make the transportation cost increase by 1.7‰. When the carbon credit policy is conducted, the carbon emissions reduce by about 1/3 and the transportation cost increases by 9%. Meanwhile, shippers are inclined to choose railway or water transportation to abide by the carbon emission limit.

Shenghua Wang, Qi Zhang, Wenyuan Wang

Improved Genetic Algorithm Based Passenger Flow Control in Subway

This paper is in the background that improvement of organization for urban rail transit operation along with its rapid development is an urgent need. Aimed at solving the organization problem of mass passenger flow, passenger flow control in subway is analyzed. To increase the control quality and efficiency, the method of improved genetic algorithm is studied. Finally, the algorithm is applied to a case study to verify its validity.

Man Jiang

Study on Protection from Stray Current in the Metro System

Aiming at solving an issue that the stray current increases the risk of corrosion of the buried metal with the increase of operation age in metro, some measures are proposed to protect the buried metal from stray current respectively on the stages of design, construction, operation, and protection in the metro system in this paper. Compared with the reference papers, CDEGS, professional software of grounding analysis, is applied for modeling as well as calculation, and factors are applied to decrease the leakage of stray current with regard to the electrical specification, like different supply modes, voltage classes, and so on. And when the metro is in operation, some measures, like the dust removal, waterproof, and passivation protection should be applied to reduce the risk of corrosion of buried metallic structures. Therefore, with the measures adopted, the risk of corrosion will be reduced greatly.

Hongbo Cheng, Zikang Xiao, Xun Wang, Nannan Sun

Energy Consumption Analysis of High-Speed Maglev Train

In this chapter, the finite element model of the linear synchronous motor is simulated and analyzed by the analysis of the high-speed maglev train. The dynamic model of the train is established from the force analysis’s point of view. In addition, for the minimum energy consumption of the traction strategy, the minimum energy consumption model is solved by taking the actual situation of the project into account. The traditional traction strategy only considers one target variable, but this chapter takes the minimum time model of the train into account while considering the energy consumption, and combines the two traction strategies and models to get a new traction strategy. And an algorithm is designed to get the optimal train running process by combining the actual operating conditions of the train.

Xiaochun Zhang, Siyuan Mu, Jinsong Kang

Risk Theory-Based Safety Evaluation of Passengers in Rail Transit Station

Station passenger flow safety status is analyzed based on risk theory and a transit station, XI’ERQI Station, is analyzed in this paper. Station passenger flow safety status is an important part of station safety status. The results indicate that the safety of passenger flow of a rail transit station is mainly determined by both the occurrence probability and the influence degree of passenger flow. Comprehensive passenger density and passenger evacuation time are chosen as the key indices for safety evaluation of the rail transit station. Combining fuzzy theory with fuzzy comprehensive evaluation method, a fuzzy comprehensive evaluation model based on passenger flow density and evacuation time is established, which is used to identify and analyze the overall safety level of a rail transit station. The results produced from the proposed model can provide useful information for preparation of the early warning of a rail transit station, and the passenger safety assurance.

Yunxiao Zheng, Yong Qin, Jianyuan Guo, Limin Jia, Jianghua Gao

Level of Service for Passage in Urban Rail Transit Station

The level of service determines the operational efficiency of the station. In order to accurately judge and predict the level of service of the passage, first of all, the evaluation index is set up. The satisfaction grading standard is established, The cloud model is used to describe the level of service based on fuzzy theory. The level of service of passage at a certain time is predicted based on Markov theory. Taking the facilities of Xizhimen station in Beijing Subway as an example, the level of passage service is evaluated and predicted, and the feasibility of the theory is verified.

Sai Chen, Jie Xu, Limin Jia, Yong Qin, Kunsheng Zhan, Jian Zhang

Acceptance Check Scheme of Integration Test and Commissioning for Urban Rail Transit

Two methods of Integration Test and Commissioning (ITC) acceptance are presented in this chapter, and the calculation method, stage division, and interface relation of ITC acceptance are analyzed and illustrated. The ITC acceptance method is divided into expert scoring method and unit engineering acceptance method. The expert scoring method, based on the hierarchical analysis model, is used to determine whether the ITC is passed through data calculation; the unit engineering acceptance method based on process control model, tracks and controls the process of the ITC subproject, subproject and inspection batch acceptance, and gives the determination whether ITC is accepted or not. The ITC acceptance of the interface debugging includes vehicle, communication, signal, power supply, safety door, rail, and other system within the scope of rail line area space and ISCS, FAS, BAS, AFC, ACS, air-conditioning, water supply and drainage, escalator, and other system within the scope of the station.

Mao Tian

Forecast of Short-Term Passenger Flow of Urban Railway Stations Based on Seasonal ARIMA Model

Forecast on short-term passenger flow of urban rail transit is the key to network operation and management, and the basis of passenger flow organization and train optimal allocation. In this chapter, a predictive model of passenger flow entering and departing is constructed, based on the model of seasonal Autoregressive Integrated Moving Average (ARIMA). First, outliers of passenger flow in time series were replaced by the linear interpolation method; Second, two methods, after considering weather conditions and air quality, are used for passenger flow forecast respectively. One is seasonal differencing, the other is by adding working day attributes as dummy variables. Third, the method of least squares was used to estimate the weight, thus a combined forecasting model for time series was constructed. After, the model has been calibrated and validated by the historical passenger flow data collected by AFC system of Beijing Metro: the error is less than 5%. This model not only considered dummy variables such as weather conditions, air quality, and working day attributes, but also quantified their impact for passenger flow. The results show that the prediction model has high accuracy.

Zhirui Guang, Jun Yang, Jian Li

Research on the Route Choice Behavior of Subway Passengers Based on AFC Data

This paper studies the route choice behavior of passengers from auto fare collection and timetable data using a method combined with Bayesian and Metropolis–Hasting sampling. First, influential factors of route choice such as in-vehicle travel time, transfer time, and in-vehicle crowding are selected. Then, formulations of these factors are established for a single passenger, which are merged into a logit model to model route choice behavior of subway passengers. Next, an algorithm that integrates Bayesian inference and Metropolis–Hasting sampling is designed to calibrate the parameters of the logit model. Finally, a case study of Beijing subway is applied to verify the validity of the developed model and algorithm.

Liping Xie, Haiying Li, Xinyue Xu

A Model of High-Density Passenger Boarding and Alighting in Urban Rail Transit Station

Passengers’ boarding and alighting is an important link between station and the train in urban rail transit system. The paper presents features of boarding and alighting of passenger flow. A model was established with two continuity equations and a formula. In that model, continuity equations about boarding and alighting are deduced based on these two characteristics, revealing the relationship between time and density. The formula of resultant about passenger flow during their boarding and alighting activities is aimed at exposing the main direction of the whole procedure. What’s more, the model was applied to Chongwenmen station in Beijing subway Line 1, the model is simplified for simulation by a mathematical application software-MATLAB, graphing directly. The result is formally described and experimented in experimental and real-world situation, which is proved to be correct and reliable. The model provides the theory foundation for safer process of boarding and alighting for actual operation and plays an important guiding meaning in daily management.

Ning Jia, Yanhui Wang

A Multi-objective Programming Model for Subway Last Train Timetabling

Subway last train timetabling focuses more on train coordination to make passengers transfer smoothly. Aiming to find an optimal balanced timetabling, a multi-objectives programming model is proposed with speed profile control for finding the optimal train velocity on sections and train dwell time at stations. Our work makes two contributions. First, this paper analyzes train movements in a line and provides an energy flow transferring method. Second, based on the analysis of train velocity and energy flow, an optimization model, in which passenger satisfaction, train trip time and network energy consumption are model objectives, is brought into the last train timetabling. Finally, to obtain an approximately optimal scheduling strategy, an artificial intelligence algorithm is proposed in particular to effectively solve the proposed model. The results of numerical experiments demonstrate the efficiency and effectiveness of the proposed method.

Wanxiao Xiang, Yanhui Wang

The Research of the Synergic Passenger Flow Control of Urban Rail Transit Line Operation

As one of the main means of public transportation, the urban rail transit plays more and more important role in passenger transport. Under the condition of limited network capacity, the realization of safe operation has become an important topic of urban rail transit. Based on the passenger flow density which intuitively reflects the traffic aggregation degree and the line collaborative operation theory, in this paper, a collaborative safety operation optimization method for urban rail transit lines based on the passenger flow is proposed. Which provides the theoretical basis for the relief of the operation pressure, the improvement of the operational efficiency, and the ensuring of the safety in daily operation of the urban rail transit.

Yiru Cui, Yanhui Wang

Application of Standardization Training of Operational Services in Rail Transit Enterprises

The quality of operational service can improve the market competitiveness of urban rail transit operators and improve the training level of rail transit service, which is conducive to the improvement of service level and the decrease of operating accident rate. In order to ensure the quality of operation and service training, promoting the construction of standardized training services is the only way. This paper analyzes the characteristics of standardized training and construction of operational service, puts forward the way of standardization construction, and analyzes the aspects of service management and other aspects, aiming at the standardization training of urban rail transit service and provides some ideas and reference.

Bin Xu, Yiming Shao

Research on Urban Rail Transit Line Collaborative Safety Operation

Based on analyzing the structure of urban rail traffic station, combined with moving patterns of train, the paper proposes security grade of passenger density and safety operation effected elements of line. Then, this paper refers to the collaborative management theory and moving patterns of train, and builds a collaborative optimization model of interval. Finally, an experiment is given to illustrate the effect of the proposed model, and the result of the experiment provides multiple plans for satisfying the different demands of the real operation. This research is significant to improve the efficiency of operation, provide guarantee to the safety of operation, and make reasonable traffic plans.

Xiaowei Shi, Yanhui Wang

Research on Train Operation Daily Schedule Based on Balanced Use

The scientific arrangement of the train operation daily schedule allocation has important significance to improve the efficiency of train operation. This paper presents a new train number and trip number matching algorithm based on improved best–worst ant system. First, train operation daily schedule is analyzed and the mathematical model of the problem is described. Then, taking the highest degree of match between the train and the trip as the optimization target, uniqueness constraint, morning peak and designated train order constraint, turnout turn-off times minimum time constraint, and convenience constraint as the constraints, a model of the train operation daily schedule based on improved BWAS is established. Finally, the simulation experiment is carried out with the actual trains, trips, and tracks information, the experimental results show that the algorithm can converge in a short time and greatly improve the balanced use of train, and verify the effectiveness of the algorithm.

Bo Wu, Zongyi Xing, Yao Zang

Evaluating the Efficiency of Urban Public Transit Enterprises Based on DEA Approach with Preference

Performance evaluation about urban public transport is one of the keys to ensure the developing of urban public transport. As the traditional evaluation model cannot reflect industry policy information and management ideas of administrators. This paper establishes DEA model with preference. And then we use triangular fuzzy numbers to calculate preference restraint cone. After establishing a set of evaluating indicator system, this paper uses DEA method with preference for public transport enterprises performance evaluation. By comparing the results of basic CCR model and the DEA method with preference, we get the advantages of DEA method with preference which can reflect more management information and the decision-maker preferences. Based on the analysis of the efficiencies, bus companies should utilize customer satisfaction as a breakthrough to improve operational efficiency.

Rong Yu, Jiaqi Sun

Research on BIM Application in High-Speed Railway OSC Operation Maintenance Management

OSC is an important part of high-speed railway system. And it plays a key role in keeping the stable operation of high-speed railway. But the traditional pattern of OSC operation maintenance management is low efficiency, high cost, and heavy workload. In view of these problems, this article introduces the situation of BIM applications in China’s railway industry. Based on demands of OSC operation maintenance management, this paper takes a deep research on OSC engineering information model encoding, modeling, and data integration. Then, this paper discusses four typical scenarios such as facility management, emergency management, operations maintenance training, and operation history management. The research suggests that BIM plays an important role in improving OSC operation maintenance management standard. This paper may provide some references for the research on related field.

Fei Meng, Tianyun Shi, Beisheng Liu

Integrated Optimization Model on Maintenance Time Window and Train Timetabling

Most of previous studies optimize maintenance time window scheduling problem under a given train schedule, leading to a relatively poor quality of maintenance time window schedule, increasing the influence on traffic assignment. In order to reduce the negative effects on maintenance schedule and improve the utilization of railway resources, we consider integrating maintenance time window scheduling and train timetabling. In this way, more reasonable maintenance time window schedule can be obtained. We propose a mixed integer programming model and in particular we focus on the characteristics of the problem, including the speed limits affected by maintenance tasks on a double-track railway line. The benefits of the proposed integrated optimization model are demonstrated by numerical experiments.

Lingyun Meng, Ce Mu, Xin Hong, Ran Chen, Xiaojie Luan, Tao Ma

Controllability of Urban Rail Transit Network

Due to the rapid development of complex network research, the controllability research of different kinds of large-scale actual network has become a research hotspot nowadays. The purpose of this study is to reveal the controllability of urban rail transit network. First, it built the urban rail transit network topology by analyzing the characteristics of urban rail transit network structure. Then, a controllability model of subway is set up based on control theory of state equation. In the model, we defined the departure train as driver node. Whether the system is controllable is determined by driver nodes. At last, we analyzed urban rail transit network structure and compared the controllability of the city of Beijing, Guangzhou, and Dongjing. The result shows that the existing subway network is uncontrollable because of the complex structure of subway. We can increase the number of driver nodes in order to make it controllable.

Lu Zeng, Yong Qin, Jun Liu, Li Wang

A Parallel Passenger Flow Management System for Outside Subway Stations Based on ACP Approach

During peak time period, the entire subway is overloaded for a large amount of passengers. To solve this problem, there are many strategies to reduce or limit the number of passengers entering the subway stations. This paper proposes the parallel passenger flow management system (PPFMS) based on ACP theory to manage the inbound passenger flow. The ACP theory, including artificial societies, computational experiments, and parallel execution, is playing an essential role in modeling and control of complex systems. For a parallel passenger flow management system, realistic artificial scenes are used to model and represent complex real scenes; computational experiments are utilized to train and evaluate a variety of estimating models; and parallel execution is conducted to optimize the passenger flow system and achieve perception and understanding of complex environments.

Huijuan Zhou, Meijie Jia, Yu Liu, Qiang Zhang, Manrong Yuan

Application of Triboelectric Nanogenerator in the Railway System

The triboelectric nanogenerator (TENG) is a new type of durable, clean, maintenance-free, low-cost, and high-reliability power generation device; so it is very suitable for energy harvesting in rail transit. This paper analyzed the power generation principle of the TENG, and the power storage mode for its pulse output; by considering the disadvantages of the standard interface circuit, an improved interface circuit has been designed, which can be used in the field of railway system to provide the power for the condition and security monitoring of the rail transportation. It expands the application range of the TENG.

Laixin Geng, Sen Bian, Teng Li, Zhao Si, Zijun Wei

Some Research on Suspension Gap Sensor of High-Speed Maglev Train

Aiming at the special temperature environment problems faced by the suspension gap sensor of high-speed maglev train, the paper studies the circuit model analysis and software compensation respectively. Through the design of differential circuit structure and temperature correction table, we solve the problem of sensor temperature drift. At the same time, using the tracking differential device to deal with the change of the vertical gap signal twice, compared with the existing acceleration signal, we get a simple fault self-detection method for the acceleration sensor.

Jun Li, Jun Wu, Junyuan Tang, Shengjun Huang

Superiority of Unit Serial Method Used in CRTS III-Type Pretensioning Ballastless Track Slab Production

High-speed railway ballastless track two-way pretensioning prestressed track slab by the unit serial method is a new type of track slab prestressed system developed in China. The research group developed the track slab production equipment and tooling and formed a 24 h production process. This is the first time in the world to achieve large-scale production of two-way pretensioning prestressed track slab through production lines. Also, this method has been tested and put into production in Shandong Linqu. Compared to the traditional matrix method of the track slab production process, this new method greatly improves the production efficiency and reduces the manufacturing cost of track slab. This can fulfill the high volume demand of track slab raised by “The Belt and Road Initiative” strategy.

Baoqun Wang, Lei Pei, Qikai Ai, Hongbin Zheng, Wei Si

The Test Plan Design of Corrosion Fault Repeat and Material Selection for a Type of PCB

The failure analysis (FA) of the PCB indicates that the connecting line of relay pin and inner structure is broken for Cl corrosion. To verify the above conclusion and find the introducing path of Cl, the accelerated corrosion test profile is designed in this paper. The failure mode is repeated successfully after six cycles and Cl is found on the connecting line of relay obviously. Besides, the different design versions of PCBs with different placed orientations are compared in this test. And the better version of PCB and better placed orientation are confirmed consequently. The following works like material replacement and PCB design refinement can benefit from the results of this paper.

Xu Wang, Shaohua Du, Yingying Yuan

Multi-hop Communication Protocol Optimization for the Linear Wireless Monitoring Network

The lifetime and latency of the railway infrastructure wireless monitoring system are vital to guarantee the stability of the monitoring system and the safety of the railway operation. In this paper, we proposed the multi-hop protocols to optimize the utility of the railway infrastructure wireless monitoring system. The lifetime maximum, latency minimum, and utility maximum models are all designed in this paper. The simulation results show that the complex objective model to maximize the utility of the system is superior to the two single-objective models. The performance in lifetime is almost to the lifetime maximum model and in latency is slightly longer than the total energy consumption minimum model. In the railway system, the two factors are all very important, the utility maximum protocol is more suitable to be used in this field.

Xiaoping Ma, Honghui Dong, Limin Jia, Yong Qin, Ruhao Zhao

Application of High Accelerated Life Testing for an Integrated Control Board

As a core part of the electric vehicle motor controller, the integrated control board plays an important role in reliability and safety of the controller running. In order to ensure the stability of the performance of the new controller, this paper carried out a high accelerated life test for the relatively weak integrated control board, so as to quickly stimulate the weakness and defects of the PCBA in design and production process. Based on the discovered faults, we can improve and optimize the design and process as early as possible. As a result, we can reduce the failure rate of the product and finally improve its inherent reliability level. In addition, this test may also provide parameters for the following reliability tests such as high accelerated stress screening test, so the plan design proposed in this paper is of great value and significance.

Yingying Yuan, Xuhui Zhang, Shaohua Du, Zaiwu Peng, Xiaochun Xiao, Jiani Zuo

Remote Monitoring System of Electrical Equipment Based on GPRS

Based on GPRS, the remote monitoring system of electrical equipment realizes the data sharing between the electrical equipment of each train and the remote terminals. This system consists of three parts: vehicle acquisition module, mobile network equipment and remote terminal. The CAN controller of the vehicle acquisition module transmits the collected power parameter data to the protocol converter, and the main controller periodically transmits the data to the remote terminal through the GPRS module, then the remote terminal stores and displays the data. The system can greatly improve the efficiency of the accident handling and improve the train running safety factor.

Yu Wang, Xuedong Jiang

YQuery: A Novel Privacy- and Integrity-Preserving Range Queries in Two-Tiered Sensor Networks

A novel protocol named YQuery was proposed in this paper to prevent attackers from gaining the information processed by or stored in storage nodes, which can not only achieve the goals of data privacy and integrity preserving, but also ensure the secure range query without incurring false positive, and allow sink node to detect the compromised storage nodes when they misbehave. To preserve privacy, YQuery uses an order encryption mechanism by adopting stream cipher to encrypt/decrypt both sensed data and queries. To preserve integrity, YQuery uses a new data structure called S2L, which allows sink node to verify the integrity of retrieved data via the so-called verification information. Analysis and experimental results demonstrate the effectiveness of YQuery.

Lvyou Yu, Jingwen Yu, Lei Wang, Linai Kuang

Simulation Study on High-Speed Milling Performance of Rail U71Mn Material

The high-speed milling of rail is one of the important directions in the development of rail maintenance technology. In order to study the high-speed milling performance of rail material, the U71Mn material milling simulation model was established using metal cutting simulation software AdvantEdge to analyze the changing rule of cutting force and cutting temperature during milling. Results show that the cutting force decreased with the increase of the milling speed of the rail, and the cutting force decreased with the cutting speed of 1200 r/min. The cutting heat increased significantly with the cutting speed, and the heat is mainly taken away by the chips, and the temperature rise is small. The research results to achieve high-speed rail milling have important guiding significance.

Chao Pan, Jianqiang Zhang, Yuelei He, Haitao Xia, Baosheng Wang

Adaptive Control with Asymptotic Stability Guarantees for High-Speed Train Systems with Uncertain Input Nonlinearities

The running process of high-speed train is a complex, multivariable, and nonlinear dynamic system with many uncertain factors. Nonlinear, time-varying and other factors make it difficult to achieve the desired performance with the linear time-invariant feedback controller. A class of adaptive learning control method is proposed to solve the problem of unknown time varying in high-speed train operation. The parametric system is used to describe the high-speed train dynamics model, and the nonlinear characteristics of the system are studied. A parameter-adaptive learning control method is given. Based on the Lyapunov functional analysis method, it is proved that the adaptive learning control method and its improved form can guarantee the train to converge to the desired speed trajectory every point. Finally, numerical simulations are conducted to verify the effectiveness of the proposed method.

Dongyue Yang, Lin Niu

Research on Key Technology of Platform Screen Door Control System for High-Speed Railway

Platform screen door (PSD) control system is a complicated distribution parameter control system. It integrates construction, machinery, electronics control, and other disciplines at an organic whole. Aiming at the problem of low localization of the original PSD products, the paper realizes the autonomy of two core technologies, door machine and door control. Control system can be divided into signal system level, local control level, and the manual operation of three control levels from high to low order. The key technology realizing the platform screen door system can be divided into the central control panel design, gating unit design, and software design. At last, the model machine of control system has been tested in platform screen doors controlling experiment.The test results show that the system has an excellent dynamic performance and a high reliability,and thus the validity and the feasibility of the proposed approach are proved.The system has the advantages of high national productivity, reducing project cost, and owning independent intellectual property right.

Zhifei Wang

Information Platform Framework for the Integrated Management of Intercity Arterial Roads

This chapter considers the comprehensive management of urban arterial roads, analyzes the current status and key components of integrated information management systems—in terms of road and transport related socioeconomic management issues—and describes the target and significance of the information system framework. By using system analysis combined with traffic engineering and relevant information system design, an integrated management information system framework, for an urban trunk road system, is put forward, including its main framework components and their functions.

Haiyang Wang

Study on a Mn–Cr–V–Ni Bainitic Forging Steel for Railway Transportation

A bainitic forging steel for railway transportation was developed and produced with secondary refining, vacuum degassing, blooming casting, and billet slow cooling, with addition of silicon, manganese, chromium, nickel, and vanadium. The influence of cooling rates on the microstructure of the Mn–Cr–V–Ni alloy was studied by optical microscopy and SEM. And the influences of heat treatment on the mechanical properties and microstructure were investigated, the microstructure analysis and tensile tests were carried after 920 °C annealing–normalizing–tempering. The results show that carbide-free bainite structure was obtained by cooling from 950 °C to room temperature at less than 0.3 °C/s, martensite structure was obtained at 8.0 °C/s. A good combination of strength and toughness was obtained through the annealing–normalizing–tempering, with tensile strength of 1353 MPa, yield strength of 1057 MPa, an elongation of 17%, a reduction of 52%, impact toughness of 110 J/cm2, and 42.0 HRC.

Yunlei Lin, Qingyue Zhou

Design of and Research on an Attendance System Based on RFID and WSN Technologies for the Rail Transportation Industry

To address the serious conflict and poor reliability issues in existing radio-frequency identification (RFID) systems, a complete set of remote wireless noncontact attendance system was designed using a 2.4 GHz active RFID system as the terminal reading device for recording employee attendance information. Combined with a wireless network architecture provided by a wireless sensor network, the system wirelessly transmits attendance information to a remote computer control system, thereby effectively improving the cumbersome wiring, poor mobility, and expansibility faults of the cable-contacted attendance system used in the Rail Transportation industry. Consequently, production safety and personnel attendance management become more convenient. The client management system communicates using LabVIEW development tools with the SQL SERVER 2008 database to achieve attendance management functions. To address the electronic tag collision problem in an active RFID system, an improved framed-slotted ALOHA anti-collision algorithm was proposed by combining the original algorithm with dynamic grouping ideas, thereby improving RFID system performance and efficiency.

Chongjun Liu, Kuangang Fan, Yi Pan, Yindong Ren
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