• 제목/요약/키워드: Tension monitoring

검색결과 151건 처리시간 0.029초

합성형 사장교의 시공단계해석 및 시공관리 시스템 개발 (Development of Structural Analysis and Construction Management System for Composite Cable Stayed Bridges)

  • 서주원;박정일;김남식;심옥진
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1994년도 가을 학술발표회 논문집
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    • pp.95-102
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    • 1994
  • This paper presents a Cable Stayed Bridge Construction Management System, which consists of Structural System Identification Method (SSIM), Error Sensitivity Analysis and Optimum Error Adjustment & Prediction System. The 1st System Identification Method builds an error influence matrix using the linear superposition of each error modes. The 2nd SSIM also considers the second error mode term, which shows good error factor estimation. The optimal cable adjustment can be accomplished within the allowable range of both cable tension and camber. The Post processor, constituted with Motif and GL library on SGI platform, is useful for monitoring construction stage management by displaying construction data, adjustment and prediction results at each construction step.

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보령댐 여수로 사면의 안정성 분석 및 유지방안 연구 (Study on the Stability Analysis and Supporting Methods for the Spillway Slopes in Boryeong Dam)

  • 정소걸;한공창;최성웅;박연준
    • 터널과지하공간
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    • 제8권1호
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    • pp.37-45
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    • 1998
  • In this study, two dimensional and three dimensional numerical analysis were performed with a finite difference code for the safe maintenance of the spillway slope of the Boryeong dam. Results of the geological survey and the stereographic projection analysis on the discontinuities were used as input data for the numerical analysis. As a result, several suggestions were given such as the reinforcement of the local tension zone, the decrease in the angle of the slope, the drawdown of the pore pressure in the slope and the removal of the upper benches. A systematic and long-term monitoring system was also suggested.

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환경모니터링이 가능한 3D 프린팅 소금쟁이 로봇 (3D Printed Water Strider Robot with Environmental Monitoring)

  • 심가현;이기학;전경한;조찬섭;김봉환
    • 센서학회지
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    • 제28권6호
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    • pp.407-413
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    • 2019
  • Using 3D printing technology, we created a biomimetic water strider robot that can monitor environments. We found ways to increase the bearing capacity of the fluid-driven water strider robot by conducting experiments then comparing with more stable robots. The controller of the robot is based on Arduino, and can be controlled wirelessly with a Bluetooth module. The speed of the robot is 7.37 cm/s, and the bearing capacity is 29 g. A lithium polymer battery that can be charged with a solar cell was used as a power source, and both the charging and driving times were also explored.

철도 노반 구축물의 광섬유 센서를 활용한 보안시스템에 관한 연구 (Study for security system of Railroad bed structure using optical fiber)

  • 김성원;송억영;배윤;황성만
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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    • pp.153-158
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    • 2004
  • The security system using optical fiber is a system, circulating infrared rays laser pulse on the optical fiber which is attached on the security fence to prevent invasion, which can show invasion position with visible and audible signal on the situation monitor if an invader cut or pull the security fence with minuteness of 10m. The optical fiber can be also applied for the bed structure stability monitoring system of high speed train as well as security system. To apply this system for high speed railroad bed structures, this system will give an alarm if it detect excessive tension, shrinkage, deflection which is beyond the limit of structure, that will prevent serious railroad accident. In this paper, we like to propose that applying this system for security and structure stability can improve confidence and stability on operation of railways

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음향방출을 이용한 극저온 환경하에서의 초전도 계자코일의 ?칭탐지에 관한 연구 (Application of AE Technique for On-line monitoring of Quencl in superconducting coil at Cryogenic Environment)

  • 이준현;이민래;권영길;류강식
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 1999년도 제1회 학술대회논문집(KIASC 1st conference 99)
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    • pp.34-38
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    • 1999
  • An acoustic emission(AE) technique has been used to monitor and diagnose quenching phenomenon in racetrack shaped superconducting magnets at cryogenic environment of 4.2K. The ultimate goal is to ensure the safety and reliability of large superconducting magnet systems by being able to identity and locate the sources of quench in superconducting magnets. The characteristics of AE parameters have been analyzed by correlating with quench number, winding tension of superconducting coil and charge rate by transport current. It was found in this study stat there was good correlation between quench current and AE parameters. The source location of quenching in superconducting magnet was also discussed on the correlation between magnet voltage and AE energy.

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UHPC 보도사장교의 장기거동에 관한 연구 (A Study on the Long-Term Behavior of UHPC Pedestrian Cable Stayed Bridge)

  • 진원종;김영진;최은석;김병석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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    • pp.109-110
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    • 2010
  • 한국건설기술연구원내에 테스트베드로서 UHPC 보도사장교(Super Bridge I)를 설계 및 완공하였고, 변형률, 가속도, 장력, 풍향풍속, 온도 등의 각종 데이터를 정기적으로 수집할 수 있는 장기계측시스템을 구축하였다. 이는 UHPC 부재의 역학적 특성 및 사용성 평가에 대한 기본 데이터를 제공하여 장대하이브리드사장교의 거동 특성을 추정하는데 큰 도움이 될 것으로 예상된다.

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자가진단형 스마트 콘크리트 개발 (Development of Self-Diagnostic Smart Concrete)

  • 김화중;김이성
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2006년도 정기 학술대회 논문집
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    • pp.82-88
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    • 2006
  • In People usually think that smart materials and smart structures have not been developed until recent years. But those kinds of sensors have already been used for sensing damage in a variety of materials and structures. Two typical examples are piezoelectric materials (e.g., PZT) and electric strain gauges. Load cell is an example that utilizes the piezoelectric property to measure the change in physical quantities occurred by applied loads, while strain gauges are used to measure the deformation of compressive and tension members. The feasibility of using smart materials is realized for a monitoring technology when those sensors are used to monitor damages at inside or outsider of the structures. In this study, a fundamental study on the development of self diagnostic smart concrete using PZT, and unsaturated polyester electric resistance sensor.

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난지도 매립지의 침출수와 가스 거동에 관한 수리 지질학적 해석

  • 김윤영;이강근
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 1996년도 경북지부 결성 및 추계학술발표회 논문집
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    • pp.102-105
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    • 1996
  • 난지도 매립지는 매립충의 불균질성과 고온의 침출수 및 가스의 흐름이 동시에 복합적으로 일어나는 현상 때문에 수리지질학적으로 매우 복잡한 지역이다. 난지도의 수문층서단위 조사와 디스크-장력 침투계(Disc tension Infiltrometer)로 불포화대 수리 특성을 추정하였으며 가스 거동 현상을 이해하기 위해 지온을 측정하였다. 매립지 주변의 지하수위 변화를 조사하기 위해 양수정과 다중-수위관측정(Multi-Level Monitoring Well)에서 수위변화를 관측하였다. 불포화대 수리특성과 기상자료를 바탕으로 매립지로의 순침투량을 추정하였다. 이것을 근거로 총 침출수 발생량을 추정하였으며, 기저 지하수면 상부에 분포하는 포화 침출수대, 즉 부유침출수의 생성 메카니즘에 대한 연구도 수행하였다.

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지반방재용 스마트 앵커의 장력측정 및 하중전이 측정 (Tension Monitoring of Prototype Smart Anchor for Geotechnical Disaster Prevention)

  • 김영상;성현종;김재민
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2010년도 정기 학술발표대회
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    • pp.90.2-90.2
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    • 2010
  • 흙막이 굴착 및 절취사면의 보강공법으로 많이 적용되고 있는 앵커의 장력을 측정하는 전기저항식 로드셀과 스트레인게이지, 바이브레이팅 와이어 (vibrating wire) 타입의 모니터링 방법은 안전관리를 위한 장기적인 모니터링에 한계를 가지고 있어 이를 개선할 수 있는 방안으로 광섬유 센서를 이용하여 강연선의 변형률을 측정할 수 있는 스마트 텐던이 개발되었다(김재민 등, 2007). 앵커를 구성하는 7연 강연선(텐던)의 중앙케이블에 삽입된 광섬유브래그격자(Fiber Bragg Grating ; FBG)센서는 기존 스트레인게이지 타입에 비해 크기가 작고 내구성이 우수하며 전자기파에 의한 노이즈 발생이 없고 하나의 리드선으로 다중점 측정(multiplexing)이 가능하여 장기모니터링에 효과적인 장점이 있다. 본 연구에서는 FBG센서를 내장한 스마트 텐던을 실대형(Prototype) 앵커(L=11.5m)에 적용하여 현장 인발실험에 의해 시공중 장력 모니터링을 수행하고 로드셀 측정결과와 비교하였고 정착부에 설치된 FBG 센서로부터 앵커의 하중전이 계측을 수행하였다.

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노인요양시설 간호사의 실무 경험 (Nurses' Experience of Practice in Nursing Homes)

  • 정승은;이순희
    • 간호행정학회지
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    • 제15권1호
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    • pp.116-127
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    • 2009
  • Purpose: This article aimed to identify nurses' experience of practice in nursing homes. Method: Using phenomenological approach for qualitative research, the participants were 8 nurses who were working at nursing homse in C city. The data was analyzed by using phenomenological methodology by Colaizzi. Results: Five theme clusters were derived from the data. They were: burden (independent decision making in clinical situations, tension of as a multifunctional member); lowered self-esteem (exhaustion, relative self-evaluation is low, comparing with others); conflict (negative image of elderly, communication break with elderly family, monitoring of nursing home staff); worth (slight improvement of elderly health state, trust and recognition, intimacy); and self-reflection (need for knowledge extension, effort towards enhancing virtue, perception of importance in their health management). Conclusion: The results showed that nursing home nurses experienced negative aspects of various nursing practice, suggesting the ways to solve their negative experience.

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