• Journal of the Korean Society for Railway
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• v.19 no.4
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• pp.498-505
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• 2016

As a basic study to develop maintenance-effective optimal ballast track in preparation for upgrading a conventional line to a high speed railway, a full-scale test that combined the components of ballast track was conducted and the characteristic of track settlement was analyzed. As a result of the full-scale test, reduction in maintenance via an increase of the elasticity of only the pad was insignificant; however, the effect increased significantly with increasing of the weight of the sleeper or with increasing of the weight of the sleeper and the thickness of the ballast together with use of a pad with high resiliency. An optimal type of ballast track, in line with upgrading the speed of a conventional line, shall be developed through cost efficiency analysis considering the maintenance cost depending on the track settlement as well as the initial construction cost.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.248-258
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• 2020

This study proposed a breakdown structure for maintenance and management technologies under the concept of comprehensive asset management at the life cycle level of infrastructure based on benchmarking with other developed countries. For this purpose, a comparative case study was performed to review and analyze the existing definitions and hierarchies for infrastructure maintenance, repair, and rehabilitation (MR&R) systems under major industrialized countries and South Korea. In accordance with the ratio of maintenance costs to GDP, the U.S., U.K, and Japan were selected to review their systems. The classifications and definitions of MR&R technologies under the laws were analyzed. The result showed that most developed countries differentiate maintenance and repair from improvement and constitute a system centered on preventive maintenance activities. On the other hand, Korea's system for facility management is not definitely classified and still focused on reactive structures, which need to be improved. In this study, as proposed, a breakdown structure established the concept of Maintenance and Management, Maintenance & Repair, and Performance Improvement. Consequently, this study could be used as the basis for the implementation of preventive MR&R activities and reasonable resource allocations from an asset management point of view.

• Journal of the Korean Society of Safety
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• v.18 no.1
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• pp.108-115
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• 2003

Bridges are rated at two levels by either Load Factor Design (LFD) or Allowable Stress Design (ASD). The lower level rating is called Inventory Rating and the upper level rating is called Operating Rating. To maintain bridges effectively, there is an urgent need to assess actual bridge loading carrying capacity and to predict their remaining life from a system reliability viewpoint. The lifetime functions are introduced and explained to predict the time-dependent failure probability. The bridge studied in this paper was built 30 years ago in rural area. For this bridge, the load test and rehabilitation were conducted. The time-dependent system failure probability is predicted with or without rehabilitation. As a case study, an optional rehabilitation is suggested, and fir this rehabilitation, load rating is computed and the time-dependent system failure probability is predicted. Based on rehabilitation costs and extended service lifes, the optimal rehabilitation is suggested.

• Journal of the Korea Society of Computer and Information
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• v.19 no.2
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• pp.11-19
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• 2014

In this paper, we build server consolidate virtualization focusing on NT server dilapidated and through analysis of the effect of this, has been presented the following results. First, it was possible to obtain an increase in the constant temperature constant humidity chamber efficiency by securing the upper surface space for computing data center mounted virtualization integration server servers multiple physical. Second, by the deployment of virtualization of a large server dilapidated, the introduction of new resources and the cost of maintaining computerized data center and reduce power consumption, the reduction of hardware introduction of additional due to the new server deployment it was possible to derive a cost reduction effect. We obtain the reduction of 89% and 79% compared with conventional consumption of cooling and power savings of the top surface, respectively. Integration of NT servers are virtualized can be expected to change in the Green-IT to contribute to providing the maintenance costs of computing centers in the future as well as current. Building a virtualization server integration applied in this paper can be similarly applied to the UNIX system and to integrate the server group other.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1278-1279
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• 2002

열차운행에 따른 신호설비 동작상태의 이상여부를 효과적으로 감시하고 신호설비의 고장 발생시 이를 신속하게 검출하여 그 원인을 진단함으로써 유지보수 고도화를 구현하기 위하여, 열차운행상황 및 신호설비 동작상태에 관한 방대한 데이터들을 효과적으로 분석 정리하기 위한 지식공학적 기법을 제안한다.

• Journal of Korean Society of Transportation
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• v.18 no.1
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• pp.7-15
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• 2000

물류에서는 재화 또는 정보의 흐름이 매우 중요하다. 그 동안 우리나라에서는 물류시스템을 물리적인 시설로 간주 시설의 공급에만 관심을 기울여 왔다. 그 결과 물류활동을 지원할 수 있을 만한 정보시스템의 구축이 충분히 이루어지지 못하였다. 본 연구에서는 화물운송을 위주로 한 화물유통체계의 합리화 방안을 모색하기 위하여 교통부분과 밀접한 연계를 갖는 첨단화물운송체계의 도입효과를 논의하고 Life-Cycle Cost의 개념을 이용하여 첨단화물운송체계의 시스템 대안을 평가하였다. 분석결과 노변 통신시스템을 이용한 시스템의 구성이 중장기적으로 유리한 것으로 평가되었다. 이는 통신비의 부담이 시설의 유지보수비의 부담보다 크기 때문이다. 그러나 노변통신시스템시설은 표준화 등의 문제로 아직 적용에 문제점들이 많으며 낙뢰 등 비용산정에 포함되지 못한 유지보수의 추가비용이 발생할 소지가 크다. 그러므로 교통시설의 특징에 따라 두 접근방식을 혼용하는 방안이 검토되어야 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.10a
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• pp.201-203
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• 2019

5G 시스템은 혁신적인 발전을 거듭하며 강력해진 기술 표준을 근간으로 초광대역 이동형 데이터 서비스, 대규모 사물통신 서비스 등을 제공하고 있다. 본 논문에서는 SW를 기반으로 한 5G의 기술 개발 방법론을 제안한다. 또, 실제 환경에서 차세대 모바일 네트워크의 성능 분석이 가능한 SW 기반의 시스템 레벨 테스트베드 및 모니터링 프로그램을 OAI(Openairinterface) 5G 연구 단체의 오픈소스를 이용하여 구현한다. 기존 하드웨어 위주의 단일 칩 시스템(SoC)을 이용한 구현은 손상되기가 쉽고 유지보수가 힘들다는 단점이 있다. 하지만 기존 하드웨어 칩을 소프트웨어 기반인 소스코드로 구현하면 유지 보수가 용이하다는 장점뿐만 아니라 하드웨어가 변경되더라도 다른 하드웨어에 호환되는 이식성 때문에 생산성이 높아지며 비용 절감의 효과도 기대할 수 있다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.4
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• pp.104-109
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• 2017

It is important to keep the distribution of the raw material mixture constant, in order to maximize the effect of the pre-mix type repair mortar, and it is also necessary to increase the performance of the mixer in order to minimize the deviation of the product. In this study, three kinds of mixer used in production sites were used to make repair mortar and the properties of each mortar were examined. As a result, it is confirmed to the difference in properties of pre-mix type repair mortar differ depending on the type of mixer, and the fluidized zone mixer showed relatively good results. In addition, it is preferable to set the mixing time to about 10 minutes to 15 minutes in order to ensure workability and optimum physical properties.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.288-295
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• 2011

The objective of this study is to develop a proper absorbent-pervious pavement. By using single graded aggregates and SAP, permeability and water absorbability of absorbent-pervious pavement are improved, and also temperature reducing effect is found out. And several tests such as compressive and flexural strength tests, and permeability/water absorption tests of absorbent-pervious pavement are carried out to verify these kind of effects. The compressive and flexural strengths are increased according to decrease of single graded aggregate size, and increase of SAP content. And the volume of water retention and absorbability are increased according to the increase of SAP content and these are also increased in small size of single graded aggregate. And about $20^{\circ}C$ of difference is observed in surface temperature between normal asphalt pavement and absorbent-pervious pavement.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.167-174
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• 2009

Due to the travelling of the train with high speed the period of maintenance activities of the ballasted track is coming to be short, and more from the residential area of the ballasted track tunnel circumference the civil appeal is increasing with railroad vibration problem. To reduce the vibration problem and a maintenance cost establishes the ballast mat in the tunnel within part segment. In this study, to estimate the vibration reduction effect of the ballast mat we have done a comparative analysis with the vibration field test by the transit train by at the ballasted track with ballast mat and the standard ballasted track without vibration protection in tunnel.