• International Journal of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.136-144
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• 2021

Railroad Systems, which are national infrastructure industries, cause unexpected property and human damage if they fail to function while operating. Accordingly, railroad facilities supporting the railroad system are areas where high reliability and safety are required. However, it is time for systematic and scientific maintenance to be taken away from the traditional maintenance methods, as the nation's railroad facilities are now aging seriously. The purpose of this study was to secure the safety and reliability of the aging railroad communication facilities and to improve their performance. The research subjects were selected as a precision diagnosis process for railroad communication facilities, and improvement points were derived through detailed precision diagnosis process analysis. It is deemed that this study can contribute based on securing stability, improving reliability, and continuous improvement of railroad communication facilities should be conducted in the operation of the entire railroad system.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.243-248
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• 2008

Seoul subway is an safety, quick, and clean public transportation to secure citizens safety. One of the most important elements of train is optimizing railroad function and need to conform railroad inspection for function maintenance. Railroad is the most biggest part of the railroad facility and it is a structure which requires sustainable maintenance. The purpose of study is to improve domestic metropolitan railroad facility inspection method and period. For this, we refer documents about present roving method, roving members and period of railroad roving. In addition, analyzed problems of railroad roving investigation method and period by examining the type and standards of railroad investigation and interviewing experts. By this, we analyzed improving plan and expectations of railroad maintenance and repair operation.

• Journal of the Korea Safety Management & Science
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• v.23 no.1
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• pp.71-79
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• 2021

The railroad facilities are intended for long-term operation as the initial acquisition costs necessary for infrastructure construction are high. Therefore, regular maintenance of railroad facilities is essential, and furthermore, system reliability through systematic performance evaluation is required. In this study, the signal control system of railroad electrical equipment was selected as the subject of research and the performance evaluation target facility selection study was conducted using AHP. The results of the study can contribute to the reliability of the signal control system as well as to the reliability of the railroad system, which is a higher system.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.224-228
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• 2007

It is focused on a methodology to establish a optimal inspection cycle of electrical facility of railroad Decision method of optimal inspection cycle is a process which establishes maintenance plan for facilities' immanent function as using reliability theory in operation term In order to ensure normal operation in a given condition, the decision method is logical for selecting effective maintenance plan to consider characteristic of system In estimation of failure rate, critical facility is selected firstly. After that, proper distribution function on each facility is decided to investigate distribution function for extraction of failure rate. Next, cost produced by the case that facility's failure is occurred is surveyed. Finally, maintenance method developed until now is investigated, before suitable model for the facility applying maintenance method is developed, and that maintenance decision is made. Therefore, this process is the method to find optimal inspection cycle for reasonable cost and effective reliability on facility.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2711-2717
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• 2011

This paper presents the classification scheme of the signal facilities on the railroad considering the construction costs and maintenance costs in a low population area. The construction costs of the new signal facility system can be compare with the costs of the present signal facilities as the classification scheme. The signal facilities on the railroad were classified as the railroad security regulations and then the scheme is considered through the LCC analysis. In order to test this research, the costs of signal facilities obtained from ones on TAEBACK railroad line. The costs categorized the construction costs, the labor cost and the maintenance costs can be effectively applied to the LCC analysis. The scheme is very useful to make a decision whether the new signal facilities on railroad in low population area is build or not in terms of the costs.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.384-389
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• 2010

Workers maintaining at the railroad trackside may collide with the train since they cannot recognize the train approaching because of the sensory block phenomenon occurred due to their long hours of continued monotonous maintenance work. To reduce these casualty accidents of maintenance workers working at the trackside of railroad, we developed the wireless communication-based safety equipment for preventing accidents. The motor-cars for maintaining trackside facility have unique operational patterns suitable for urban environment. The several mechanism for developed safety equipment are represented in this paper.

• International Journal of Railway
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• v.7 no.3
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• pp.80-84
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• 2014

The purpose of this paper was to review Intelligent Compaction (IC) techniques, which is regarded relatively new to the railroad roadbed construction activity. Most of civil structures are built on roadbed that supposed to provide adequate load bearing support to the upper structure through the qualified compaction process. However, it is not uncommon for structure failure attributed to inadequate compaction control take place in field sites. Unlike traditional compaction control method to check field density at several locations, IC techniques continuously measure various compaction quality indices that represent compaction uniformity. In this paper, a series of literature review relevant to IC techniques was conducted to provide concise summary on the following categories: 1) background of IC technique; 2) Summary of IC vendors and basic principles; 3) modeling of IC behavior, and 4) case study along with correlation between IC with other measurements. In summary, IC technologies seem to be promising in future railroad construction to achieve better compaction quality control so that the serviceability of railroad can be ensured with minimizing rehabilitation and maintenance activities.

• Journal of the Korean GEO-environmental Society
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• v.19 no.2
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• pp.37-44
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• 2018

Ballasted track has been widely used due to its flexibility. However, the plastic deformation of ballasted track causes the evolution of track geometrical errors, and hence it requires continuous maintenance; increase in number of trains, weight, and speed expedites maintenance frequency and cost as well. Ballast stiffness is well-known as an indicator of design and maintenance. In this regard, this paper aims to suggest the method to measure ballast track stiffness using light-weight deflectometer (LWD) and thus verify its applicability as a maintenance measure. Preliminary field tests determined simple field testing protocol to measure track stiffness. The apparent ballast stiffness by LWD shows good corelation with TQI (Track Quality Index) and maintenance length. That is, as average of apparent stiffness increase, TQI and tamping length decrease exponentially. Therefore, apparent stiffness can be used as an index for ballast condition assessment.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1752-1759
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• 2007

In the new Seoul-Busan high speed railroad construction specially city center passage roadbed establishment is recommended the staibility for the existing subway tunnel segments of Busan subway line No. 1 and No.2. regarding the appearance condition, a quality condition and the durability of the objective facility site exact inspection, and it evaluates the numerical analysis which uses MIDAS GTS it leads and there is the objective of the place where the stability of the objective facility and this tunnel it investigates. To immediacy of the on-the-spot inspection result whole facility it is a condition where the reinforcement which is simple not to be hindrance is necessary, 2nd Line case it is a condition which transfer is good but the general defect and the damage which occur from the tunnel of NATM type were confirmed part. While roadbed establishment constructing that the continuous maintenance is necessary, it is judged. The result of 1st, 2nd Line maximum sinkage, unequal sinkage and the lining stress of numerical analysis are within permission and the damage degree is appearing with the fact that the degree it will can disregard it is slight. But it enforces necessary Pre-grouting in order to minimize an actual tunnel face conduct and when the tunnel is excavated it is judged with the fact that necessary to minimize the outflow possibility.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.4
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• pp.695-703
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• 2016

The maintenance method for the electrical facility of high speed railway has been evolved from inspection by personnel to the automated way by the detection devices. In particular, the signalling equipment in order to increase the safe and efficient operation of the trains is required to maintain normal operation by periodic maintenance. Because the return current gives the most important effects to the wayside equipment in case of the failures, a method is needed to measure the unbalanced rate of return current on the train at high speed driving. The Hot Box Detector(HBD) device that is installed at track-side has a function to recognize the abnormal axle box by detecting the temperature that occurs in the axle of train passing over its device. In order to implement the measurement equipment for unbalanced rate of return current and axle temperature, the design method is proposed and the experimental test results by test bed are included in the paper.