• Research on GW-SH Turnout External Locking Device Based on Double-slider Mechanism
• Liu Zhenhua, Wang Hua
• 2023 Vol. 20 (4): 1-4. DOI:10.3969/j.issn.1673-4440.2023.04.001
• Abstract ( ) PDF (2072KB)( )
•  In general, the turnout switching equipment of high-speed railways has operated well on site since its application in China, but there are still some problems, such as external locking device transition jamming due to the considerable expansion of switch rails, more serious wear of some parts and more maintenance workload. In order to further improve the adaptability and reliability of this equipment and reduce the on-site maintenance workload, the structural scheme of GW-SH turnout external locking device is proposed. The device applies a double-slider mechanism with an elastic roller structure and friction reduction measures, which not only improves safety and reliability, but also meets the needs of high-speed railways in a better way by controlling the expansion of the switch rails of large-number turnouts and reducing transition jamming failures and on-site maintenance workload. 
  
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• Influence of Distributed Capacitance of Cables on AC Switch Transition Circuits
• Wang Yong, Zhao Ze
• 2023 Vol. 20 (4): 5-10. DOI:10.3969/j.issn.1673-4440.2023.04.002
• Abstract ( ) PDF (4433KB)( )
• The phase interruption protector relay of a three-phase AC switch transition circuit is not deenergized after the loss of phase occured in an outdoor switch machine. In order to solve this problem, the internal mechanism of the influence of the multi-source distributed capacitance on this circuit is revealed through the in-depth study on the field test results in different scenarios under both normal and loss-of-phase conditions, and through the detailed analysis of the working principles of the analog phase interruption protector and the digital phase interruption protector. Moreover, the measures for engineering improvement and suggestions on how to modify the industry standard are put forward.
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• Discussion on Signal Design Schemes for EMU Storage Yards of High-speed Railways
• Shi Lei
• 2023 Vol. 20 (4): 11-13,25. DOI:10.3969/j.issn.1673-4440.2023.04.003
• Abstract ( ) PDF (1094KB)( )
• This paper analyzes the setting of the EMU storage yards of high-speed railways, takes an EMU storage yard close to a station as an example, and proposes a signal design schemes using the train operation method and the shunting operation method respectively. By comparing the train operation modes and signal aspect modes, the advantages and disadvantages of each scheme are analyzed in detail. These design schemes can provide a reference for the signal design of such EMU storage yards.
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• Test Sequence Generation Approach for On-board Train Control Equipment Based on DRPP
• Wang Shuo, Wu Peidong, Zhang Youbing
• 2023 Vol. 20 (4): 14-20. DOI:10.3969/j.issn.1673-4440.2023.04.004
• Abstract ( ) PDF (1242KB)( )
• In the process of generating test sequences for the functional scenarios of On-board Equipment in Train Control (OBE), the disadvantage is that the existing method cannot make full use of the concatenated relationship of sub-sequences in other scenarios. To solve this problem, an optimized method for the generation of test sequences based on Directed Rural Postman Problem (DRPP) is proposed. A model of strongly connected directed graphs is constructed according to the sub-sequences of all functional scenarios of the equipment under test. In addition, the required arc-set is created based on the functional scenario covered by the test sequences. By using the minimum-cost feasible flow algorithm of a capacity network with a lower limit, an Eulerian graph containing the required arc-set is produced at the minimum cost, after which the optimal test sequence is generated by Hierholzer's algorithm. In an example of the functional scenario of CTCS-2 on-board equipment, the optimized method is compared with the existing one. The result shows that the method described in this paper can make the best use of the concatenated relationship of all sub-sequences to generate the optimal test sequence which covers the specified functional scenario. In the level-transition scenario and mode-transition scenario, the cost of test sequences is reduced by 4.2% and 1.4% respectively.
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• Design of Safe Digital Input and Output Signal System Based on ARM+FPGA Architecture
• Ma Minggang
• 2023 Vol. 20 (4): 21-25. DOI:10.3969/j.issn.1673-4440.2023.04.005
• Abstract ( ) PDF (1167KB)( )
• The design of a safe digital input and output system using the ARM+FPGA architecture scheme can efficiently, real-time, and accurately process safe input and output signals. The design concept is to encode the input signal safely with generating a unique expected code for performing the fault detection; and to match the output signal with a secure coding sequence and read back the status feedback signal to determine whether it is abnormal; Through safety and fault prevention analysis, this design can meet the requirements of safety integrity level of SIL4 in the safety certification standard by using a 56 bit code sequence in the application of railway products.
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• Application of Heterogeneous Dual-core Processors in Multi-channel Analog Acquisition Systems
• Li Anfu
• 2023 Vol. 20 (4): 26-32,39. DOI:10.3969/j.issn.1673-4440.2023.04.006
• Abstract ( ) PDF (1266KB)( )
• This paper introduces the concept and calculation principle of True Root Mean Square (TRMS), and expounds on how to use software algorithm to calculate TRMS. In this paper, a 32-channel analog signal TRMS acquisition system is described in detail, which is based on F28M35, a heterogeneous dual-core processor. Its C28 core focuses on data acquisition and TRMS algorithm processing, and its M3 core focuses on human-computer interaction, communication and other tasks. The two cores run independently, exchanging information through IPC without interfering with each other, and each has its own advantages. In addition, the paper introduces the hardware circuits, parameter settings, the functions of each software module, how the software and hardware work together, and the IPC communication mechanism between the cores, thus providing a more detailed description of the design of the acquisition system. This design leads to much lower system costs, higher technical level and  better adaptability.
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• Discussion on Unified Authentication of 5G-R MCX Roaming Users
• Yin Weihai
• 2023 Vol. 20 (4): 33-39. DOI:10.3969/j.issn.1673-4440.2023.04.007
• Abstract ( ) PDF (1333KB)( )
• After roaming, a user of 5G-R Mission Critical X-Service (MCX) needs to pass the validity verification and authorization of the Identity Management Server (IDMS) for unified authentication in order to securely access the MCX service resources of the visited place.This paper studies and analyzes IDMS network deployment and interactive authentication, etc., and proposes a variety of networking methods such as IDMS shared by all railways, two-level IDMS of all railways/railway bureaus, and IDMS deployed by railway bureaus, as well as their corresponding interactive authentication mechanisms.
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• Analysis of CTCS-3 Wireless Timeout Cases Caused by Functional Defects of Base Station Software
• Xu Wenyuan
• 2023 Vol. 20 (4): 40-45. DOI:10.3969/j.issn.1673-4440.2023.04.008
• Abstract ( ) PDF (3290KB)( )
• In a cell of the cellular network of a high-speed railway managed by China Railway Shanghai Group Co., Ltd., CTCS-3 wireless connection timeout caused by the sudden drop in uplink level to -100 dBm during the operation of several trains. This paper takes such recurring problem as an example to find a solution. Through the analysis of the base station log and the reproduction of on-site results in the laboratory and other means, the cause of the problem is finally identified that is the intelligent self-healing mechanism of this type of base stations starts the radio-frequency loopback of the carrier-frequency board when an RRU handles no traffic for a long time. By turning off such self-healing function, the fault is corrected, ensuring the stable and orderly operation of trains on this high-speed railway.
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• Case Study on GSM-R Network Optimization in Zhenjiang Hub Area
• Mei Jing
• 2023 Vol. 20 (4): 46-51,72. DOI:10.3969/j.issn.1673-4440.2023.04.009
• Abstract ( ) PDF (6874KB)( )
• The railways in the hub area of Zhenjiang include the existing Shanghai-Nanjing Intercity Railway passenger dedicated line, the Beijing-Shanghai High-speed Railway (from Beijing South Railway Station to Shanghai Hongqiao Railway Station) and the newly connected Lianyungang-Zhenjiang High-speed Railway (passenger dedicated line), all of which are controlled by CTCS-3 signal systems. In terms of the introduction of Lianyungang-Zhenjiang High-speed Railway into the hub area of Zhenjiang, it is not only necessary to ensure that the existing GSM-R network is not affected, but also to meet the network coverage demands of new lines. Therefore, reasonable optimization and adjustment measures need to be taken to satisfy the coverage demands of each line. In this paper, the GSM-R coverage scheme of this hub area is studied and the corresponding optimization scheme is proposed, which provides an idea for the optimization of the radio-sharing sections of multiple other CTCS-3 lines.
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• Research on Operation and Maintenance System for Railway Equipment Rooms Based on AIOps
• Yuan Zhenjiang
• 2023 Vol. 20 (4): 52-55,67. DOI:10.3969/j.issn.1673-4440.2023.04.010
• Abstract ( ) PDF (1065KB)( )
• The traditional design idea of power and environment monitoring systems for equipment rooms focuses on monitoring, which aims at finding equipment faults and helping the maintenance professionals with the repairing. However, there are some disadvantages to these traditional systems, such as decentralized management, a low level of maintenance management and a low level of data visualization. In order to find out the potential failures and to make railway equipment rooms safer, this paper proposes the research on an operation and maintenance management system based on AIOps for the equipment rooms of railways. This new method realizes the early warning of the status of the equipment rooms by the remote monitoring of the environment and various devices in these rooms, and by fully mining the massive amount of historical data collected during the operation of the system, utilizing big data, alarm correlation analysis and visualization.
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• Research on External Interface Technology of Regional Rail Transit Collaborative Transportation and Service System
• Qin Ning, Xie Hehuan
• 2023 Vol. 20 (4): 56-62. DOI:10.3969/j.issn.1673-4440.2023.04.011
• Abstract ( ) PDF (1413KB)( )
• This paper introduces the concept, composition and functions of a collaborative transportation and service system and its demonstration application in a rail transit base in Chongqing. This paper focuses on the types and functions of the external interfaces of the system and the corresponding data acquisition and data processing technology. The interface server constructed according to the method described in this paper has been successfully connected with the existing urban rail operation system in the rail transit base, and has become an important part of the urban rail collaborative transportation and service system of Chongqing. The implementation of the demonstration project of this collaborative system can improve the overall transport capacity, safety guarantee and service level of urban rail in Chongqing, and provide a reference for the development of multi-standard collaborative technology of regional rail transit.
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• Research on Fully Automatic Speed-restriction Operation Mode
• Chang Feng
• 2023 Vol. 20 (4): 63-67. DOI:10.3969/j.issn.1673-4440.2023.04.012
• Abstract ( ) PDF (1447KB)( )
• In view of the fault that a train loses positioning in the fully automatic operation mode, it is necessary to quickly regain the positioning or operate the train to the nearest platform area. In this paper, the application process, movement authority  distance and the handling of scenarios in the fully automatic speed-restriction operation mode (FRM) are comprehensively analyzed and studied, and the solutions are put forward. The following scenarios are discussed: operation in a section on a main line, the turning  back of a train, and train movements in a depot, etc.
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• Monitoring Scheme for Hohhot Metro Signal Network Based on Interoperability
• Lü Tao, Su Xiaofei
• 2023 Vol. 20 (4): 68-72. DOI:10.3969/j.issn.1673-4440.2023.04.013
• Abstract ( ) PDF (1515KB)( )
• Through the research on the characteristics of the interoperable metro signal network in Hohhot, this paper expounds on the importance of network monitoring for improving the maintenance of CBTC signal systems. This paper also introduces the design ideas and optimization directions of a network monitoring scheme for rail transit by describing the packet capture  tools deployed in the DCS system and the methods for monitoring and analyzing information according to RSSP-I Protocol, and by sharing real operation cases.
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• Research on Temporary Speed-restriction Scheme of CBTC System of in Intermittent Mode
• Wu Jinyuan, Wang Jing
• 2023 Vol. 20 (4): 73-76. DOI:10.3969/j.issn.1673-4440.2023.04.014
• Abstract ( ) PDF (1061KB)( )
• This paper aims at improving the safety and efficiency of a train passing through a Temporary Speed Restriction (TSR)  section in the intermittent  mode of a signal system. Firstly, the problems existing in traditional TSR in such intermittent mode are analyzed. Then, taking the TSR scheme for the CBTC system in the intermittent mode of the Hangzhou-Haining Intercity Railway as an example, this paper puts forward a scheme of CI TSR levels (with three levels: 25 km/h, 40 km/h and 60 km/h), and expounds on the function distribution and the changes in the interface protocols of each subsystem of the signal system involved in the proposed scheme. This new scheme changes the transmission, confirmation, implementation and feedback of TSR information from manual control to machine control, and has achieved good results when applied to actual operation and production.
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• Discussion on Scheme of Fast-Transfer Ticket Check for Caoqiao Station of Beijing Daxing International Airport Express
• Meng Fanchen, Zhai Xi
• 2023 Vol. 20 (4): 77-81. DOI:10.3969/j.issn.1673-4440.2023.04.015
• Abstract ( ) PDF (1456KB)( )
• Beijing Daxing International Airport Express (Daxing Airport Express),which is a dedicated rail transit line connecting the central city and Beijing Daxing International Airport, has ticket system and fares that are different from those of other lines. It is inconvenient to transfer passengers between this Airport Express and other lines with non-paid areas. Based on the layout of the transfer station halls and existing transfer modes of Caoqiao Station (Caoqiao Zhan), a fast transfer scheme is analyzed in terms of ticket gate settings, ticket types and the handling of exceptions, etc. This scheme can serve as a reference for the subsequent construction and renovation of transfer stations of airport express lines, or for transfers between lines with different ticket systems, so as to realize the integrated development of rail transit.
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• Analysis of Differences between Drafting Rules of Equipment Technical Standards and Engineering Construction Standards
• Xu Hui
• 2023 Vol. 20 (4): 82-89. DOI:10.3969/j.issn.1673-4440.2023.04.016
• Abstract ( ) PDF (3389KB)( )
• By comparing Directives for standardization--Part 1: Rules for the structure and drafting of standardizing documents (GB/T 1.1-2020) and Regulations on the preparation of engineering construction standards (JB [2008] No. 182), the latter of which is developed by the former Ministry of Construction of the People’s Republic of China, this paper analyzes and explicates the differences between the drafting rules of equipment technical standards and engineering construction standards in terms of the drafting stages, structures, names and text preparation of these standards, hoping to provide writers of such documents with a clearer description of the methods for compiling different types of standards, so as to improve the standardization and accuracy of drafting.
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• Research on Standard Preparation Process and Drafting Rules of China Railway Society
• Leng Ning, Chen Hongyu
• 2023 Vol. 20 (4): 90-95. DOI:10.3969/j.issn.1673-4440.2023.04.017
• Abstract ( ) PDF (1300KB)( )
• This paper briefly introduces the concept of association standards, the position and scope of the association standards of the China Railway Society (CRS) considering the needs of the standardization technical committees of CRS and the working groups undertaking the drafting tasks. This paper also provides a detailed study on these CRS standards in terms of the management modes, classification, stages of formulation and composition of documents, as well as the workflows and rules of drafting different types of standards, offering  positive guidance to the professionals involved in the drafting and preparation of CRS association standards and in standardization.
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• Research on Special Control and Signal Aspect and Indication Rules of Overseas Railway Signaling
• Zhao Li
• 2023 Vol. 20 (4): 96-100. DOI:10.3969/j.issn.1673-4440.2023.04.018
• Abstract ( ) PDF (943KB)( )
• Combining the basic theory of the United Kingdom(UK) railway signaling engineering design and the basic knowledge of the United States(US) railway signaling, this paper introduces related guidance documents of operating rules and signaling control principle adopted in overseas railways, elaborates the unique control methods and the difference regarding to signal aspect and indication rules in the UK and the US railways and puts forward suggestions for the implementation of overseas railway signalling engineering. It is expected to provide some reference for equipment development and engineering implementation of overseas projects.
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• Research on Signal Power Supply System for Hungary-Serbia Railway
• Liu Jialiang
• 2023 Vol. 20 (4): 101-104. DOI:10.3969/j.issn.1673-4440.2023.04.019
• Abstract ( ) PDF (1129KB)( )
• The Hungary-Serbia railway is the first high-speed railway led by China in Europe, and the first high-speed electrified railway in Serbia with a speed of 200 km/h. The requirements for power supply systems and UPS schemes of the signaling equipment are quite different from those in China. According to the local requirements of the Serbia section of the railway, this paper puts forward a technical scheme for the signal power supply system, and studies the adaptability of domestic equipment and technical scheme for meeting the technical requirements specified in local regulations and specifications. This research will provide guidance and experience for Chinese railway equipment "going out " and re-innovation.
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