• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.55 no.11
• /
• pp.463-467
• /
• 2006

A direct current electric power system is one of the most important power source in a metro railway system. As railway system is growing up today, the importance of DC electric power system is emphasized. The study for systemization and standardization of design and operation technique in DC electric power system is undergoing nowadays. For these studies, the development of standard analysis model for metro railway electric power system is required. In this paper, a standard analysis model for metro railway electric power system which is using PSCAD/EMTDC program is proposed. The proposed model is explained and the validity is shown by using the case studies.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.1411-1417
• /
• 2006

The DC electric power system is the most important power source in a metro railway system. As metro railway system is expanded recently, the importance of DC electric power system is emphasized. Furthermore, the study for systemization and standardization of design and operation technique in DC electric power system is undergoing nowadays. For these studies, the development of standard analysis model for metro railway electric power system is required. In this paper, a standard analysis model for metro railway electric power system which is using PSCAD/EMTDC program is developed. The developed model is explained and the validity is shown by using the case studies.

• Journal of the Ergonomics Society of Korea
• /
• v.22 no.1
• /
• pp.81-94
• /
• 2003

The British railway safety research group has developed a risk assessment model for the railway infrastructure and major railway accidents. The major hazardous factors of the railway infrastructure were identified and classified in the model. The frequency rates of critical top events were predicted by the fault tree analysis method using failure data of the railway system components and ratings of railway maintenance experts, The consequences of critical top events were predicted by the event tree analysis method. They classified the Joss of accident due to railway system into personal. commercial and environmental damages. They also classified 110 hazardous event due to railway system into three categories. train accident. movement accident and non-movement accident. The risk assessment model of the British railway system has been designed to take full account of both the high frequency low consequence type events (events occurring routinely for which there is significant quantity of recorded data) and the low frequency high consequence events (events occurring rarely for which there is little recorded data). The results for each hazardous event were presented in terms of the frequency of occurrence (number of events/year) and the risk (number of equivalent fatalities per year).

• Proceedings of the KSR Conference
• /
• 2005.11a
• /
• pp.7-14
• /
• 2005

A Structure of a system is usually described as same as an architecture, but they are basically different. The architecture has a broader meaning than a system structure. In other words, an architecture can include many of system structures. So, to define the architecture, we need to consider how functions of a system are consisted and integrated. The architecture defined is applicable to railway safety management systems, and it can be made as a new model for railway safety systems, which is useful to systematize railway safety regulations. To establish the architecture as applicable to railway safety regulations, it is required to compare between regulation relations by analyzing roles before/after executing railway safety regulations. Therefore, in this research, we reviewed and classified different types of regulation conditions and safety requirements for railway systems and a variety of conditions before/after railway safety regulations changes are compared by defining system architectures subject to National railway safety.

• Journal of the Korean Society for Railway
• /
• v.14 no.2
• /
• pp.87-93
• /
• 2011

This work describes an availability model of highly available systems to achieve Five-9's availability. Modern railway systems have raised users' expectations of powerful "always on" services. The crucial characteristics of these highly available services are essential to many modern businesses area, such as telecommunications, railway systems, information operations, Web-based businesses, and so on. The architecture-based model of system availability is useful to assess the feasibility of meeting a high availability target. The Markov model approach is straightforward for relative system engineers to adapt when they model highly available system failure and the failure recovery process. This work proposed the improved availability model through UML2.0. It is shown that the architecture-based model of system availability is a good reasonable by its application of the railway systems.

• Journal of the Korea Society of Computer and Information
• /
• v.21 no.5
• /
• pp.57-64
• /
• 2016

In this paper, we propose the design of railway safety common data model to provide common transformation method for collecting data from railway facility fields to Real-time railway safety monitoring and control system. This common data model is divided into five abstract sub-models according to the characteristics of data such as 'StateInfoMessage', 'ControlMessage', 'RequestMessage', 'ResponseMessage' and 'ExtendedXXXMessage'. This kind of model structure allows diverse heterogeneous data acquisitions and its common conversion method to DDS (Data Distribution Service) format to share data to the sub-systems of Real-time railway safety monitoring and control system. This paper contains the design of common data model and its DDS Topic expression for DDS communication, and presents two kinds of data transformation case studied for verification of the model design.

• Journal of the Korean Society for Railway
• /
• v.4 no.2
• /
• pp.47-54
• /
• 2001

Railway companies have been faced with many changes in the railway environment. To cope immediately with the influence of environment and to improve productivity, an efficient train operation system and related core technologies must be introduced. The railway system is composed of large scale infrastructures and high-cost trains. Simulation method is one of core technologies and also efficient tool for planning and analyzing these kinds of complex system. In this research, we review basic simulation programming models and present a modeling for the elements of railway system such as rail-line infrastructure, train, time table and operational route. Additionally, some considerations on the development of multi-train traffic simulator for KyongBu-line are discussed.

• Proceedings of the KSR Conference
• /
• 2005.11a
• /
• pp.1-6
• /
• 2005

To improve safety management of railway and cope with the factors to threat technical and social safety, we need to establish railway safety management system based on analysis of hazards and assessment of risk for railway system. So we have to conduct PHA(Preliminary Hazard Analysis) first to understand weak points and factors to possibly threat safety using analysis of related data such as past accident/incident data and safety regulation and classification standards of hazards/causes of railway accidents. Therefore in this research, we led types/dangerous events/causes of risks/factors of risks from hazard log developed based on railway accident classification and hazards of railway accident. PHA model for domestic railway system will be used in risk analysis and risk assessment of railway accident.

• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.163-166
• /
• 1997

In order to shorten head-way time on existing railway lines without any change of signal block length between stations, it is a realistic optional way to change the control method of train signal, i.e. to modernize the cab signal using transponder. A new signalling system of operation pattern control technique is suggested as new model to increase the railway traffic efficiency. Through the computer simulation of this model, the train head-way time by the fixed signalling system and the new pattern control system is analyzed.

• Journal of the Korean Society for Railway
• /
• v.10 no.4
• /
• pp.431-437
• /
• 2007

This paper describes the dynamic modeling of a railway vehicle when it is under braking force. It is important for the enhancement of braking performance to establish a proper dynamic model of a railway vehicle because the braking performance is affected by some dynamic forces generated by a railway vehicle when it undergoes braking. In this paper, a dynamic model for one vehicle is suggested to compute the dynamic behavior of a railway vehicle in the HILS(Hardware In-the-loop Simulation) system for the railway vehicle braking devices. To simplify the dynamic model, friction between a wheel and a rail is assumed that there exist only the static and the dynamic friction forces. Static friction coefficient is also assumed to be a function of the running speed. Some simulations are carried out with various braking forces, and the braking characteristics according to the change of the braking force are discussed. This study can provide some fundamental results to construct the HILS system for braking devices of a railway vehicle.