• 제목/요약/키워드: Maintenance in Structure

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Ad hoc 네트워크에서 제어메시지 부하를 감소시키는 클러스터 유지 방법 (A Cluster Maintenance Scheme to Reduce the Control Overhead in Mobile Ad hoc Networks)

  • 왕기철;방상원;조기환
    • 한국정보과학회논문지:정보통신
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    • 제31권1호
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    • pp.62-69
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    • 2004
  • 클러스터 구조는 Ad hoc 네트워크내의 전체 호스트로 데이타를 방송하는 경우에, 재전송 되는 메시지의 수를 감소시킨다. 이러한 클러스터 구조의 이점을 보존하기 위해 클러스터 유지방법이 이용된다. 그러나 기존의 클러스터 유지방법들은 이웃정보 파악을 위한 제어메시지 외에도 클러스터 재구성을 위한 추가적인 메시지 교환을 필요로 한다. 이로 인해 클러스터 구조의 유지에 따른 이점은 크게 약화된다. 본 논문에서는 클러스터 구조의 중첩성을 이용하여 Hello 시간에 클러스터 헤드들만 제어메시지를 broadcast 전송하고 일부 멤버 호스트들은 제어메시지의 unicast 전송을 통해 분리된 게이트웨이를 파악하는 클러스터 유지방법을 제안한다. 제안하는 방법은 클러스터 재구성이 필요할 때에도, 각 호스트간에 전송되는 제어메시지를 최소한으로 줄이기 위한 전략을 사용한다. 제안된 방법은 이 과정에서 2흡 클러스터의 정의를 파괴하지 않으며, 클러스터를 완전히 분산된 방법으로 생성한다. 본 논문에서 제안한 방법은 실험결과에 의해 LCC(1)보다 우수한 것으로 평가된다.

화재피해 콘크리트의 유지관리 및 시공성능 향상을 위한 표준화방안 (The Standardized Methods for Improvement of Maintenance and Performance Construction of Deterioration caused by Fire damage)

  • 서동구;김동은;김봉찬;권영진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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    • pp.16-18
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    • 2013
  • A fire outbreak in a reinforcement concrete structure looses the organism by different contraction and expansion of hardened cement pastes and aggregate, and causes cracks by thermal stress, leading to the deterioration of the durability. So, concrete reinforcement structure is damaged partial or whole structure system. Therefore accurate diagnosis of deterioration is needed based on mechanism of fire deterioration in general concrete structures. Fundamental information and data on the properties of concrete exposed to high temperature are necessary for accurate diagnosis of deterioration. In this study, consider case of investigation methods and repair work in fire damaged structure concrete.

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균열발생 지하철 본선구조물의 안정성 연구 (A Study on Stability of Cracked Main Structure in Subway)

  • 우종태;임성순
    • 한국구조물진단유지관리공학회 논문집
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    • 제3권3호
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    • pp.187-194
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    • 1999
  • In this study, a series of items on the safety and stability of cracked main structure in subway are investigated and analyzed. Cracks due to dry contraction under the construction can be found when a tensile stress of cross section is higher than tensile strength at a value of coefficient of dry contraction $200{\times}10^{-6}$. It is concluded that there is no problems when load carrying capacity, that is, an ability of resisting loads of structure is enough in this analytical model. Also, it is concluded that this model has a desirable serviceability because a width of bending crack is lower than allowable one.

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Effect of relative stiffness on seismic response of subway station buried in layered soft soil foundation

  • Min-Zhe Xu;Zhen-Dong Cui;Li Yuan
    • Geomechanics and Engineering
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    • 제36권2호
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    • pp.167-181
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    • 2024
  • The soil-structure relative stiffness is a key factor affecting the seismic response of underground structures. It is of great significance to study the soil-structure relative stiffness for the soil-structure interaction and the seismic disaster reduction of subway stations. In this paper, the dynamic shear modulus ratio and damping ratio of an inhomogeneous soft soil site under different buried depths which were obtained by a one-dimensional equivalent linearization site response analysis were used as the input parameters in a 2D finite element model. A visco-elasto-plastic constitutive model based on the Mohr-Coulomb shear failure criterion combined with stiffness degradation was used to describe the plastic behavior of soil. The damage plasticity model was used to simulate the plastic behavior of concrete. The horizontal and vertical relative stiffness ratios of soil and structure were defined to study the influence of relative stiffness on the seismic response of subway stations in inhomogeneous soft soil. It is found that the compression damage to the middle columns of a subway station with a higher relative stiffness ratio is more serious while the tensile damage is slighter under the same earthquake motion. The relative stiffness has a significant influence on ground surface deformation, ground acceleration, and station structure deformation. However, the effect of the relative stiffness on the deformation of the bottom slab of the subway station is small. The research results can provide a reference for seismic fortification of subway stations in the soft soil area.

현장계측을 통한 기존선 철도 구조물 접속부의 거동분석 (Dynamic Analysis of Structure's Approaches through Field Tests in the Conventional Railway)

  • 박준오;이상배;홍원표
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.1864-1874
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    • 2007
  • Korean trains pass many mountain areas, so the volume of structures like bridge and tunnel has large part of railway lines. Train speed-up naturally needs a straight line in railway, then structures are increasing, and the length of structure has more than 70% in Kyongbu high-speed railway. The stiffness of bridge and tunnel is higher than the soil in the roadbed in spite of dynamic difference in vibration and displacement. Differences in stiffness have more dynamic effects and increase the deformation and destruction in the track and roadbed. This influences passenger's comfort and the safety of operation, and it needs more track maintenance. This study selected tunnel with ballast track, tunnel with concrete track, and structure's approaches with short maintenance cycle in the roadbed and had track acceleration tests and track liner inspections using track master in the field. This study will measure periodically to structure's approaches which have very fast track irregularity and analyze dynamic differences and track irregularity near structure's approaches, so realize the cause of track irregularity of structure's approaches and use basic data for reasonably strengthening method of structure's approaches.

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스마트구조물 계측시스템에 관한 실험적 연구 (An Experimental Study on Health Monitoring System of Smart Structure)

  • 윤희준;유병억;한창평;안형준
    • 한국구조물진단유지관리공학회 논문집
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    • 제10권2호
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    • pp.191-202
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    • 2006
  • 구조물을 설계할 때 사용하는 컴퓨터 프로그램들은 구조물에 작용하는 각각의 조건을 고려한 최적의 설계를 할 수 있도록 도움을 준다. 하지만 컴퓨터 프로그램은 단순화시키고 일반화시킨 조건들을 적용하기 때문에 그 결과들은 실제 구조물의 거동을 정확히 설명할 수 없다. 이러한 문제점들을 극복하기 위해서 도입된 것이 스마트 구조이고 스마트 시스템을 통해 구조물을 상시 계측함으로서 실제 구조물의 정확한 거동을 파악할 수 있다. 본 연구는 실험을 통해 기존의 구조설계방법에 의한 구조물의 거동과 실제 구조물의 거동을 비교하여 계측시스템의 타당성 검토와 함께 앞으로의 발전가능성을 알아보고자 한다.

유지보수에 특화된 웹 문서 작성기의 설계 및 구현 (Design and Implementation of a WebEditor Specialized for Web-Site Maintenance)

  • 조영석;권용호;도재수
    • 융합보안논문지
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    • 제7권4호
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    • pp.73-81
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    • 2007
  • 웹 사이트들은 정보의 양이 방대해지고 웹 문서들의 잦은 생성, 삭제와 수정이 반복되면서 더욱 복잡한 구조의 양상을 띠게 되었으며 사용자가 원하는 최적의 정보에 접근하는 방법 또한 예측하기 힘든 구조를 가지게 되었다. 또한 웹 사이트를 처음 만드는데 들이는 노력에 비해 유지 보수에는 요구되는 비용 때문에 적은 노력을 들이고 있다. 이런 환경에서 웹 문서간의 관계와 그 관계들의 유효성을 분석하여 그 정보가 제공된다면 개발자 뿐 아니라 관리자들도 효과적이고 효율적인 서비스를 제공할 수 있다. 웹 사이트 전체의 구조를 쉽게 파악할 수 있고 하이퍼링크의 유효성을 확인하기 위해 웹 문서의 분석을 통해 하이퍼링크의 구조를 추출하고 체계적인 방법으로 웹 사이트를 관리 하는데 필요한 여러 가지 정보를 제공하여야 한다. 본 논문에서는 HTML 태그를 분석하여 하이퍼링크 정보를 추출, 문서간의 관계를 체계적으로 구조화 하고 관계를 이루는 하이퍼링크가 유효한지 여부를 판단하여 알려주는 두 가지 방법을 사용하여 웹 사이트의 유지 보수를 지원함과 동시에 새로운 문서를 생성 편집할 수 있는 웹 문서 작성 방안을 제안한다.

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2차원 및 3차원 모델링에 의한 터널구조물의 구조해석 (Structural Analysis of Tunnel Structures by Two and Three Dimensional Modeling)

  • 김래현;정재훈;임성순
    • 한국구조물진단유지관리공학회 논문집
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    • 제6권3호
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    • pp.97-102
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    • 2002
  • Two dimensional Analysis has been applied to most of tunnel lining design in these days. Two dimensional analysis uses beam or curved beam element for finite element method. But because the behaviors of tunnel concrete lining structure is near to shell, it is required to model the tunnel lining as shell structure for safety design of tunnel lining structure. In this paper, two dimensional analysis by beam element and the three dimensional analysis by shell element of tunnel concrete lining are studied, in which 3 type of tunnel lining and lateral pressure factors are considered. As results of the study, three dimensional analyses of the behavior of tunnel concrete lining structure considering lateral pressure factor shows that the moment of three dimensional analysis is greater than those of two dimensional analysis. The results shows that three dimensional analysis is necessary for safety design of tunnel lining.

공공교통 전동차 안전운행을 위한 RIMS 프로젝트 적용의 성공요인 연구 (A Study on the Successful Factors in the Application of RIMS Project for the Safe Operation of Rolling Stocks in the Public Transportation)

  • 이강원;방연근;손영진
    • 한국철도학회논문집
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    • 제9권5호
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    • pp.555-560
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    • 2006
  • This study finds out and suggests success factors for the application of RIMS project through the case study of Seoul Metro and literature survey. The successful application of RIMS needs expert knowledge and concept of BOM, standardization of maintenance planning, check lists of heavy maintenance inspection, organization structure of rolling stock maintenance offices, material management system of warehousing and the process of parts repairing between offices, connection of material ordering system, problem solving of circular spare parts administration among inspection, maintenance, and material organizational units, systemic serial number management of parts with RFID, daily closing diary connected with work process chart, and sufficient period of RIMS's test run. RIMS contributes to real time management of rolling stock maintenance, transparency of management, reliability of train operation, customer satisfaction, and management innovation.

옹벽 구조물의 표준 DB화 방안 및 유지관리 특성 연구 (A Study on Characteristics of Maintenance and Standarization Plan Concerned with DB of Retainging Wall)

  • 이송;심민보
    • 한국구조물진단유지관리공학회 논문집
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    • 제4권4호
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    • pp.129-140
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    • 2000
  • Retaining wall is a constructed structure in order to construct road, rail, building for effective use and obtainments of the limited ground. Recently, many kinds of research have been actively developed for a standardization and information to the maintenance and management of bridge, tunnel, road. With the works of database construction of that, many kinds of data with respect to statistics is cumulated. Database work of retaining wall is wholly lacking and lagged behind in the works of database construction. This paper suggests classification system on inspection data. On the basis of that, code work with classification system was practised and DB program of inspection data of retaining wall was developed. And input work for a data of maintenance and management was practised. The purpose of this paper is to suggest a kind of statistics data and investigate a characteristics of inspection using statistic data on retaining wall.

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