• 제목/요약/키워드: broken

검색결과 1,942건 처리시간 0.03초

레일절손검지장치 현장적용 및 안정화에 관한 연구 (A Study on the Application on Site and Stability of Broken Rail Detection Equipment)

  • 최시행;차관봉;이종성;정수영;이희성
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
    • /
    • pp.2082-2089
    • /
    • 2011
  • This study is examination of application on site for performance and stability of real-time broken rail detection equipment development system about connection, welded part occurring data errors of broken rail monitoring system. As a result of analysis about data collected in Seoul Metro No.2 Subway from Mar. 2010 to Jan. 2011, we found it is possible to detect crack location(Thermit welding) within the margin of error of ${\pm}1m$ accurately as the first attenuation was -1.2dB and the second was -1.3dB.

  • PDF

깊이 영상을 이용한 3D 프린팅 기반 환자 맞춤형 안와 임플란트의 설계 및 제작 (3D Printing Based Patient-specific Orbital Implant Design and Production by Using A Depth Image)

  • 서우덕;김구진
    • 한국멀티미디어학회논문지
    • /
    • 제23권8호
    • /
    • pp.903-914
    • /
    • 2020
  • In this paper, we present a novel algorithm to generate a 3D model of patient-specific orbital implant, which is finally produced by the 3D printer. Given CT (computed tomography) scan data of the defective orbital wall or floor, we compose the depth image of the defect site by using the depth buffering, which is a computer graphics technology. From the depth image, we compute the 3D surface which fills the broken part by interpolating the points around the broken part. By thickening the 3D surface, we get the 3D volume mesh of the orbital implant. Our algorithm generates the patient-specific orbital implant whose shape is accurately coincident to the broken part of the orbit. It provides the significant time efficiency for manufacturing the implant with supporting high user convenience.

입자법을 이용한 댐 붕괴의 수치 시뮬레이션 (NUMERICAL SIMULATION OF DAM-BROKEN PROBLEMS USING A PARTICLE METHOD)

  • 이병혁;정성준;김영훈;박종천
    • 한국전산유체공학회지
    • /
    • 제13권1호
    • /
    • pp.28-34
    • /
    • 2008
  • A particle method recognized as one of the gridless methods has been developed to investigate the nonlinear free-surface motions interacting to the structures. The method is more feasible and effective than convectional grid methods for solving the non-linear free-surface motion with complicated boundary shapes. The right-handed side of the governing equations for incompressible fluid, which includes gradient, viscous and external force terms, can be replaced by the particle interaction models. In the present study, the developed method is applied to the dam-broken problem on dried- and wet-floor and its adequacy will be discussed by the comparison with the experimental results.

분산형 복합재료의 강화재 손상 증분형 이론 (Incremental Theory of Reinforcement Damage in Discontinuously-Reinforced Composite)

  • 김홍건
    • 한국마린엔지니어링학회:학술대회논문집
    • /
    • 한국마린엔지니어링학회 2000년도 춘계학술대회 논문집(Proceeding of the KOSME 2000 Spring Annual Meeting)
    • /
    • pp.122-126
    • /
    • 2000
  • In particle or short-fiber reinforced composites cracking of the reinforcements is a significant damage mode because the broken reinformcements lose load carrying capacity . The average stress in the inhomogeneity represents its load carrying capacity and the difference between the average stresses of the intact and broken inhomogeneities indicates the loss of load carrying capacity due to cracking damage. The composite in damage process contains intact and broken reinforcements in a matrix, An incremental constitutive relation of particle or short-fiber reinforced composites including the progressive cracking damage of the reinforcements have been developed based on the Eshelby's equivalent inclusion method and Mori-Tanaka's mean field concept. influence of the cracking damage on the Eshelby's equivalent inclusion method and Mori-Tanaka's mean field concept. Influence of the cracking damage on the stress-strain response of the composites is demonstrated.

  • PDF

불균질입자강화 복합재료의 최적설계를 위한 손상메커니즘 해석 (Analysis of Damage Mechanism for Optimum Design in Discontinuously-Reinforced Composites)

  • 조영태;조의일
    • 한국공작기계학회논문집
    • /
    • 제13권4호
    • /
    • pp.106-112
    • /
    • 2004
  • In particle or short-fiber reinforced composites, cracking or debonding of the reinforcements cause a significant damage mode because the damaged reinforcements lose load carrying capacity. The average stress in the inhomogeneity represents its load carrying capacity, and the difference between the average stresses of the intact and broken inhomogeneities indicates the loss of load carrying capacity due to cracking damage. The composite in damage process contains intact and broken reinforcements in a matrix. An incremental constitutive relation of discontinuously-reinforced composites including the progressive cracking damage of the reinforcements have been developed based on the Eshelby's equivalent inclusion method and Mori-Tanaka's mean field concept. Influence of the cracking damage on the stress-strain response of the composites is demonstrated.

3상 농형 유도전동기 회전자 바의 고장진단에 관한 연구 (A Study on The Diagnosis of Broken Rotor Bars in Three Phase Squirrel-Case Induction Motor)

  • 김근웅;권중록;이갑재;김완기
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2001년도 하계학술대회 논문집 B
    • /
    • pp.635-637
    • /
    • 2001
  • The faults of the squirrel cage induction motor is grew increasingly complex as the faults resulting in the shorting of a stator winding and the broken rotor bar or cracked rotor end ring, bearing faults, and so on. The users of electrical machines initially relied on simple protections such as over-current, over-voltage, earth-fault, etc. to ensure safe and reliable operation. but this method cause heavy financial losses and the threat of safety therefore it has now become very important to diagnose faults at there very inception. in this paper, we are going to discuss the detection method of broken rotor bar of squirrel cage induction motor by the motor current signal analysis(MCSA) and the opening terminal voltage signal analysis.

  • PDF

Removal of a broken needle using three-dimensional computed tomography: a case report

  • Kim, Jin-Ha;Moon, Seong-Yong
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • 제39권5호
    • /
    • pp.251-253
    • /
    • 2013
  • Inferior alveolar nerve block obtained maximum anesthetic effect using a small dose of local anesthetic agent, which also has low a complication incidence. Complications of an inferior alveolar nerve block include direct nerve damage, bleeding, trismus, temporary facial nerve palsy, and etc. Among them, the major iatrogenic complication is dental needle fracture. A fragment that disappears into the soft tissue would be hard to remove, giving rise to a legal problem. A 31-year-old woman was referred for the removal of a broken needle, following an inferior alveolar nerve block. Management involved the removal of the needle under local anesthesia with pre- and peri-operative computed tomography scans.

입자법을 이용한 댐 붕괴의 수치 시뮬레이션 (NUMERICAL SIMULATION OF DAM-BROKEN PROBLEMS USING A PARTICLE METHOD)

  • 박종천;이병혁;정성준
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2007년도 추계 학술대회논문집
    • /
    • pp.258-263
    • /
    • 2007
  • A particle method recognized as one of the gridless methods has been developed to investigate the nonlinear free-surface motions interacting to the structures. The method is more feasible and effective than convectional grid methods for solving the non-linear free-surface motion with complicated boundary shapes. The right-handed side of the governing equations for incompressible fluid, which includes gradient, viscous and external force terms, can be replaced by the particle interaction models. In the present study, the developed method is applied to the dam-broken problem on dried- and wet-floor and its adequacy will be discussed by the comparison with the experimental results.

  • PDF

등고선 벡터라이징을 위한 끊어진 등고선의 자동 연결 기법 (An Automatic Connection Scheme of Disconnected Contours for the Vectorizing of Contours)

  • 전일수;남인길
    • 한국산업정보학회논문지
    • /
    • 제5권4호
    • /
    • pp.60-66
    • /
    • 2000
  • 본 논문에서는 등고선 자동 벡터화 시스템 개발을 위해 등고선의 끊어짐을 포함하는 스캔된 등고선 이미지에서 등고선을 연결하는 기법을 제안한다. 제안된 기법에서는 등고선의 세선화를 먼저 수행하고 나서 끊어진 선들을 연결한다. 등고선들은 끊어짐이 존재하면 끝점들을 가지므로 이들 끝점 쌍들을 연속적으로 연결하여 하나의 등고선이 하나의 연결요소를 이루도록 연결한다. 제안된 기법은 효율적인 등고선 자동벡터화 시스템을 개발하는데 적용될 수 있다.

  • PDF

곡면 복층유리 열파손에 관한 실험적 연구 (An Experimental Study on Thermal Breakage in Curved Double Glazing)

  • 남중우;이재현
    • 한국태양에너지학회:학술대회논문집
    • /
    • 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
    • /
    • pp.543-548
    • /
    • 2012
  • The use of glass applied to curved surface as a building material has increased in recent years. However, the curved glass is difficult to guarantee the quality in process of making it into double glazing, So it is vulnerable to thermal breakage. In this paper, when the glass broken during experiments, surface temperature difference on curved double glazing was compared to that of heat strengthened glass and flat glass. As a result, flat single glass was broken at temperature difference of 100~140 degrees but curved double glazing was broken at that of 40~60 degrees. Therefore, curved double glazing is more vulnerable than flat double glazing to thermal breakage, so it should be considered when applied to building facade.

  • PDF