• Proceedings of the KIEE Conference
• /
• 2007.10c
• /
• pp.214-216
• /
• 2007

With the arrival of ubiquitous networking environment, it has been needed to build up the u-infrastructure for railway, and so the realization of ubiquitous rail system could be preferred. We have studied the direction for development of technology for realizing u-rail system through the analysis of the condition and demand on railway system, and investigated the requirements, level of technology and applicability of information infrastructure for realizing u-Rail. And also analyzed the technology based on railway information to determine the role of existing information system and connect it, which is adequate for u-Rail and the project selection.

• Proceedings of the KIEE Conference
• /
• 2005.07b
• /
• pp.1562-1564
• /
• 2005

The study for ubiquitous computing infra is proceeding actively, it make possible to use service and access network anywhere, anytime because of wire/wireless communication technology and progress of hardware. Domestically, study for the network mobility support technology which is the key technology for future ubiquitous computing realization have progressed, but that is insufficient. Especially, there is no study for independent mobility support study about railway wireless network. So, this study propose network mobility management technology for mobile network infra in railway and proper network model in train.

• Journal of the Korean Society of Safety
• /
• v.38 no.2
• /
• pp.104-111
• /
• 2023

Rolling stock maintenance, which focuses on preventive maintenance, is typically implemented considering the potential harm that may be inflicted to passengers in the event of failure. The cost of preventive maintenance throughout the life cycle of a rolling stock is 60%-75% of the initial purchase cost. Therefore, ensuring stability and reducing maintenance costs are essential in terms of economy. In particular, private railroad operators must reduce government support budget by effectively utilizing railroad resources and reducing maintenance costs. Accordingly, this study analyzes the reliability characteristics of components using field data. Moreover, it resolves the problem of determining an economical replacement interval considering the timing of scrapping railroad vehicles. The procedure for determining the optimal replacement interval involves five steps. According to the decision model, the optimal replacement interval for the onboard signal device components of the "A" line train is calculated using field data, such as failure data, preventive maintenance cost, and failure maintenance cost. The field data analysis indicates that the mileage meter is 9 years, which is less than the designed durability of 15 years. Furthermore, a life cycle in which the phase signal has few failures is found to be the same as the actual durability of 15 years.

• Journal of the Korean Society for Railway
• /
• v.10 no.2 s.39
• /
• pp.231-242
• /
• 2007

As railroad industry faces the new Renaissance era, effective and efficient maintenance methods for rolling stock operation are required with advanced railroad technology. All kinds of railroad systems such as high-speed long-distance train, metropolitan mass transit and light rail require systematic maintenance technology in order to maintain the safe railroad operation. Simulation models for regular operations of the example maintenance center are developed. In this study, standard maintenance procedures, layout, equipments, and number of workers of Siheung Metropolitan Railroad Maintenance Rolling Stock Depot are considered. The proposed simulation models are developed using simulation package ARENA. After simulation, four types of observations are analyzed. First, the bottleneck operation is identified. Second, the relationship between maintenance center size, number of workers and cycle time is analyzed. Third, the scheduling performances between PERT/CPM and Critical Chain Project Management(CCPM) are compared. Lastly, the simulation results according to worker's working coverage shows expanding the worker's coverage decreases the cycle time and increases throughput per train. However, workers are to be fully trained to do multiple skill work.

• Journal of the Ergonomics Society of Korea
• /
• v.34 no.2
• /
• pp.103-113
• /
• 2015

Objective: This study proposes a systematic process to present the analysis methods and solutions of organizational root causes to human errors on the railroad. Background: In fact, organizational root cause such as organizational culture is an important factor in the safety concerns on human errors in the nuclear power plant, railroad and aircraft. Method: The proposed process is as follows: 1) define analysis boundary 2) select human error taxonomy 3) perform accident analysis 4) draw root causes with FGI 5) review root causes analysis with survey 6) chart analysis of root causes, and 7) propose alternatives and solutions. Results: As a result, root causes of the organizations like railroad and nuclear power plant came from the educational problems, violations, payoff system, safety culture and so forth. Conclusion: The proposed process does predict potential railroad accident through retrospect error analysis by building new human error taxonomies and problem solution. Application: This study would contribute to examination of the relationship between human error-based accidents and organizational root causes.

• Proceedings of the KSR Conference
• /
• 2007.05a
• /
• pp.1187-1192
• /
• 2007

Recently, many organizations such as, including government, railroad operational, railroad facilities managemental and research authorities have made a lot of efforts to identify and prevent hazards from leading to accidents and solve them all over the railroad industry. Railroad total safety technology development project conducted as one of national R&D projects has established business formation structure based on system engineering as an effort to define and give a solution to facing problems in the field of railroad. This paper is building procedures to verify the outcomes derived from this project. The verification process is the one for verifying the outcome produced in the final stage of the project or during the project. It makes sure that the system is satisfying the system requirements through verification of the outcomes produced after conducting the project for verification. We've made verification plan for technically reasonable verification using verification process developed through this research, and established master verification plan in the level of 15 detailed projects for interim and final outcomes produced.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.42 no.6
• /
• pp.887-892
• /
• 2022

Due to various reasons (normally financial constraints in developing countries), it becomes common to change of the business model from state-run projects to Private Investment Projects (Public Private Partnership) in the global railway businesses. However, due to the nature of railroads compared with other types of infrastructure such as roads and others, railway business require considerable construction cost and O&M cost through the business development, construction, and operation and management stages. Therefore, private investment railway projects, especially in developing countries, can be problematic in terms of the potential for uncertainty when return on investment cannot be guaranteed. In order to strengthen the competitiveness of domestic companies when entering overseas railroad PPP projects, this study proposes PPP-related risks and their countermeasures by reviewing global railroad trends and identifying Korea's weakness in managing international railroad projects.

• Journal of Korean Society for Atmospheric Environment
• /
• v.27 no.2
• /
• pp.191-200
• /
• 2011

A way to adsorptively remove indoor carbon dioxide at relatively lower concentration under ambient temperature was studied. A small lab-scale carbon dioxide adsorption and desorption reactors were prepared, and 5A and 13X zeolites were packed in this reactors to investigate their adsorption and desorption characteristics. The inflow carbon dioxide concentration was controlled to 5,000 ppm, relatively higher concentration found in indoor spaces with air quality problems, by diluting carbon dioxide with nitrogen gas. The flow rate was varied as 1~5 L/min, and the carbon dioxide concentration after this reactor was constantly monitored to examine the adsorption characteristics. It was found that 5A adsorbed more carbon dioxide than 13X. A lab-scale carbon dioxide desorption reactor was also prepared to investigate the desorption characteristics of zeolites, which is essential for the regeneration of used zeolites. The desorption temperature was varied as $25{\sim}200^{\circ}C$, and the desorption pressure was varied as 0.1~1.0 bar. Carbon dioxide desorbed better at higher temperature, and lower pressure. 5A could be regenerated more than three times by thermal desorption at $180^{\circ}C$. It is required to modify zeolites for higher adsorption and better regeneration performances.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.1298-1300
• /
• 2002

This paper suggested that the technical specification of tilting train EMU for speed up on existing lines. High speed strategy of existing lines are the modification of railway system which are made on cant, lengths of transition curves, the catenary system and train system. Tilting technology is more useful a strategy for speed increases on existing lines with low investment needed. We performed a feasibility study which is considered out real track conditions and designed propulsion and braking system of tilting EMU system.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.1741-1744
• /
• 2003

This study is a kind of preliminary research in order to propose and suggest the plan of performance improvement for the speed-up through the examination of operational condition on the field for signal system facility on the conventional railway, in order to obtain the elemental technology from the technical development for utilization of high speed train which will be run on the Korea Conventional Line and, finally, in order to propose the specification of signal system using for high speed and the scheme of establishment for the optimal signal system.