• International Journal of Railway
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• v.2 no.1
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• pp.30-36
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• 2009

Crack and its damage of structure concrete in both FBS and TBS ballastless track are presented. The cause of concrete crack is analyzed. According to corresponding quantitative equation, effective technical measures to depression crack of concrete are put forward, at the same time the rationality of elastic ratio for HGT has been proved. At last, by the analysis of the characteristic of high-speed train, which are serving in the open air, bearing fatigue load, the short time for maintenance window and high speed of service, technical requirement for concrete repair material, repair technology and repair tools of ballastless track structure are presented.

• Smart Structures and Systems
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• v.28 no.6
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• pp.779-789
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• 2021

Cracks in railway sleeper are an inevitable condition and has a significant influence on the safety of railway system. Although the technology of railway sleeper condition monitoring using machine learning (ML) models has been widely applied, the crack recognition accuracy is still in need of improvement. In this paper, a two-stage method using edge detection and convolutional neural network (CNN) is proposed to reduce the burden of computing for detecting cracks in railway sleepers with high accuracy. In the first stage, the edge detection is carried out by using the 3×3 neighborhood range algorithm to find out the possible crack areas, and a series of mathematical morphology operations are further used to eliminate the influence of noise targets to the edge detection results. In the second stage, a CNN model is employed to classify the results of edge detection. Through the analysis of abundant images of sleepers with cracks, it is proved that the cracks detected by the neighborhood range algorithm are superior to those detected by Sobel and Canny algorithms, which can be classified by proposed CNN model with high accuracy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.1
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• pp.129-133
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• 2016

This paper insists that the accessibility and transfer facility has also to be included in railway investment because railway mode can not be, what is called, a door to door service. At present those facility are not included in the railway investment with them in negligence. Since those facility is not treated with railway system there is no room to get a budget from the central government. This paper suggests that all the measurements have to be implemented, based on the LOS (Level of Service) of accessibility and transfer at railway stations. The LOS has to be as low as reasonably practical (ALARP) which can be derived from the consensus between government and citizens. Also, a couple of procurement methods are suggested for accessibility and transfer facility separately. Finally, improvement of regulations are also suggested.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.1
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• pp.14-25
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• 2017

This study aims to verify the causal relationship between service quality of the urban railway operating agency and users' behaviors, targeting the urban railway users. The perceived ease of use of the urban railway service quality had an influence on tangibility and convenience, and the perceived usefulness was significant to all attributes; therefore, it is judged that reliability, correspondence and safety should be improved to increase the users' perceived ease of use of the urban railway service quality. Based on these study results, the urban railway operating agency should make an effort to increase the perceived ease of use and usefulness of the urban railway to improve the service quality, to positively change the users' attitudes toward use, and to make the positive change connected to the intention of reuse and intention of recommendation, the users' behavior intentions.

• Journal of the Korean Society for Railway
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• v.15 no.5
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• pp.459-466
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• 2012

Due to the issues such as omission of data, document based management, maintenance based on measurement data and wire-based network, it is difficult existing maintenance system for railway bridges to act to diverse characteristics of site and environmental changes in real time. With these reasons, there are many constraints in establishing active maintenance strategies for railway bridges. To solve these issues, this study suggests an integrated maintenance business model based on practical utilization and information management based on BIM technology to build a smart maintenance operation system based on ubiquitous computing for railway bridges. To secure its development and practical applications, a quantitative evaluation by questionnaire analysis was performed. Therefore, it is expected that the suggested model will be utilized as a framework model in order to build the smart maintenance operation system from collection of maintenance data to action for railway bridges.

• Journal of the Korean Society for Railway
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• v.18 no.2
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• pp.149-156
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• 2015

It is necessary to determine real path for urban railway users in order to allocate revenues between urban railway organizations. Out of several algorithms used to determine optimal routes, the k-path algorithm based on link-label has been utilized. However, this k-path algorithm has certain flaws. For example, optimal route can change depending on the travel and walking time, transfer penalty, and so on. Also, this algorithm cannot take into account the characteristics of users, who prefer express train to normal trains. In this paper, an algorithm is proposed to determine one single optimal route based on the traffic card data. This method also can search for an optimal path in conjunction with the railway timetable.

• Journal of Energy Engineering
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• v.24 no.1
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• pp.17-23
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• 2015

Electrical door system is one of the most essential items for the successful commercial operation of the railway vehicles. Nowadays, reliability values of electrical door system have a tendency to be included in technical requirements for design and manufacturing of rolling stocks. Manufacturer shall meet the reliability target values of electrical door system which is proposed by railway operator in procurement contract book. Railway operator shall approve the supplier's the reliability target values based on maintenance operation data. Railway operators are in the transition stage from the framework of maintenance interval based on time to the framework of maintenance interval based on distance. In this study, failure rates of the electrical door system currently used in railway vehicles are collected from maintenance field data. Failure rates are analyzed by using Minitab. Several kinds of plan for improving reliability are also suggested. It is necessary to keep studying on reliability prediction methodology, applying it in the field and implementing on improvement of reliability through feedback as well. Further, it will be useful for determining new maintenance policies or changing maintenance intervals for existing railway vehicles.

• Proceedings of the KIEE Conference
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• 2007.10c
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• pp.214-216
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• 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 KSR Conference
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• 2003.10b
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• pp.163-169
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• 2003

In order to develop domestic railway technology, it is necessary that manufacturing technology of turnout should be kept up with update level, because turnout is the core component of high speed railway. Manganese crossing made of high manganese alloy steel is a important component of turnout. So far, this could not have been welded with rail steel due to metallic problem in Korea. However, joint technology hereunder between manganese crossing and rail by using Flash Butt Welding which is developed by Kangwon Railtech Co., Ltd is the state of the art and enable to realize rail continuousness in turnout section, speed up train velocity, reduce maintenance cost, and enhance riding quality.

• Proceedings of the KIEE Conference
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• 2004.10a
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• pp.233-234
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• 2004

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.