• 제목/요약/키워드: broken

검색결과 1,934건 처리시간 0.036초

전동차부품의 손상진단 및 그 대책 (The damage diagnosis and countermeasure of rolling stock parts)

  • 박수중;안영환;임상윤
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 춘계학술대회 논문집
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    • pp.1626-1630
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    • 2007
  • This dissertation finds out trouble types and occurrence regions using the faulty statistics of nondestructive test items in rolling stock parts of the Seoul Metro and using mechanical test about defective and broken parts with broken surface observation, cutting examination about trouble region, hardness experiment and tensile test. Also this dissertation finds out cause of trouble and damage through observation of microscopic formation using metallurgical microscope and scanning electron microscope, residual stress measurement about welding parts and damage diagnosis about defective and broken parts. Moreover it will present the improved plan of nondestructive method about trouble and the removal method of defect and repair welding and find solutions of reliability in parts and preventive maintenance.

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폴리우레탄계 마이크로캡슐의 제조 및 그의 파괴 거동 (The Preparation of Polyurethane Microcapsule and Its Breaking Behavior)

  • 박형인;김애경;이웅의;최창남
    • 한국염색가공학회지
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    • 제10권2호
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    • pp.37-44
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    • 1998
  • In this study, the polyurethane microcapsules containing disperse dye were prepared by in-situ polymerization method using hexamethylene diisocyanate (HDI, aliphatic type) and m-xylene diisocyanate(XDI, aromatic type) with ethylene glycol (EG) And the size, shape, particle size distribution, and breaking behavior of microcapsules prepared were investigated. The size and shape of microcapsule were observed by scanning electron microscope (SEM) . The particle size distribution was analyzed by image analyzer. The breaking behavior of microcapsule was checked by measuring the optical density of solution that the disperse dye was dissolved after the microcapsule was broken by constant pressure. The particle size was inversely proportional to the stirring speed, and the size of microcapsule prepared from HDI and EG was smaller than that of microcapsule prepared from XDI and EG. Aliphatic type microcapsule was broken easily, compared with aromatic type one. It was considered due to the difference of reactivity between HDI and XDI. And the microcapsule prepared by stirring strongly was broken easily.

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하치조신경 전달마취 중 파절된 주사바늘

  • 장중희;송민석;김현민;김남훈;엄민용;구현모;이준규;양병은
    • 대한치과의사협회지
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    • 제44권2호통권441호
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    • pp.139-144
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    • 2006
  • Local anesthesia is routine procedure in dental practices and has several complication. One of them, needle fracture is not uncommon in past, but rare in recent. The number of cases reported in the literature of broken needle in local anesthetic procedure has shown a marked decrease since the use of disposable spiral-constructed dental needle began. This complication results from lack of patient cooperation, inaccurate anesthetic technique, sudden movement of patient, error in the manufacturing procedure, use of short needle, and bending before use. Most common site is pterygomandibular space during inf. alveolar nerve block. In two patients, we removed broken needles under general anesthesia without complication. So we report cases with review of literatures.

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Robust Diagnosis Algorithm for Identifying Broken Rotor Bar Faults in Induction Motors

  • Hwang, Don-Ha;Youn, Young-Woo;Sun, Jong-Ho;Kim, Yong-Hwa
    • Journal of Electrical Engineering and Technology
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    • 제9권1호
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    • pp.37-44
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    • 2014
  • This paper proposes a new diagnosis algorithm to detect broken rotor bars (BRBs) faults in induction motors. The proposed algorithm is composed of a frequency signal dimension order (FSDO) estimator and a fault decision module. The FSDO estimator finds a number of fault-related frequencies in the stator current signature. In the fault decision module, the fault diagnostic index from the FSDO estimator is used depending on the load conditions of the induction motors. Experimental results obtained in a 75 kW three-phase squirrel-cage induction motor show that the proposed diagnosis algorithm is capable of detecting BRB faults with an accuracy that is superior to a zoom multiple signal classification (ZMUSIC) and a zoom estimation of signal parameters via rotational invariance techniques (ZESPRIT).

Fuzzy Measure를 이용한 화재감지기의 기본설계

  • 백동현;김기화
    • 한국화재소방학회논문지
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    • 제10권3호
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    • pp.19-28
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    • 1996
  • 본 논문은 Fuzzy Measure를 이용한 화재감지기의 사고판정을 결정하는 방법을 제시한 것으로 Belief measere를 기본으로하여 Dempster의 결합 Rule을 사용하였다. 감지기에서의 화재 판정 결정은 화재(F), 비화재(N)의 2가지로 하였으며, 이를 판정하기 위해 현재 사용되고있는 열, 연기감지기에 대한 정정값에 대해 Fuzzy Rule을 적용하여 시뮬레이션 하였다. 그 결과 Fuzzy Rule의 수를 많이 적용할수록, 최종동작은 Bel(F)의 값을 높게 할수록 확실한 화재 판별이 가능함을 입증하였다.

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A Method for Indentifying Broken Rotor Bar and Stator Winding Fault in a Low-voltage Squirrel-cage Induction Motor Using Radial Flux Sensor

  • Youn, Young-Woo;Hwang, Don-Ha;Sun, Jong-Ho;Kang, Dong-Sik
    • Journal of Electrical Engineering and Technology
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    • 제6권5호
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    • pp.666-670
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    • 2011
  • In this paper, a method for detecting broken rotor bar and stator winding fault in a low voltage squirrel-case induction motor using an air-gap flux variation analysis is proposed to develop a simple and low cost diagnosis technique. To measure the leakage flux in radial direction, a radial flux sensor is designed as a search coil and installed between stator slots. The proposed method is able to identify two kinds of motor faults by calculating load condition of motors and monitoring abnormal signals those are related with motor faults. Experimental results obtained on 7.5kW three-phase squirrel-cage induction motors are discussed to verify the performance of the proposed method.

웹 페이지에서 참조무결성 제약조건에 관한 연구 (A Study on Referential Integrity Constraint on Web Page)

  • 유남현;손철수;김원중
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2004년도 춘계종합학술대회
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    • pp.569-572
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    • 2004
  • 다수의 사람들이 관리ㆍ운영하는 많은 분량의 HTML 문서들로 이루어진 웹사이트들의 경우에는 현수참조(Dangling Reference)와 오문참조(Inaccurate Contents Reference)와 같은 깨진 링크(Broken Link)를 관리하는데 많은 어려움이 따른다. 즉, HTML 페이지의 내용 중 연결구조에 관련된 부분을 변경하거나 삭제하는 경우 문서들간의 연결구조에 대한 무결성(Integrity)을 보장하기가 어렵다. 본 논문에서는 Parent 페이지와 Child 페이지에서의 무결성 제약조건(Integrity Constraint Condition)들을 조사하여 정의하고, 확장 UML로 표현하는 방법에 대해 연구하였다.

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의도 고출력 전자파에 의해 오동작 되는 CMOS소자의 전류특성 (Current Characteristics of CMOS device Broken by Intentional High Power Electromagnetic Wave)

  • 황선묵;홍주일;한승문;박신우;허창수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1516-1517
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    • 2007
  • This paper investigated the breakdown effect of the CMOS device by impact of high power electromagnetic wave. The experiments employed a waveguide to study the current characteristics of CMOS device broken by high power electromagnetic wave. The CMOS device were composed of a LED drive circuit for visual discernment. Also CMOS device broken by high power electromagnetic wave was observed by power current. The CMOS device were broke by high power electromagnetic wave at about 10 kV/m and when power current is 75 mA. Based on the result, CMOS devices should show plan to protect the CMOS devices by high power electromagnetic wave. And the database from this experiment should provide the basis for future investigation.

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Traveling televisual texts: transnational adaptations of "Doctor Foster" into Korea's "The World of the Married" and the Philippines' "The Broken Marriage Vow"

  • Ralph Edward P. Sekito
    • 수완나부미
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    • 제16권1호
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    • pp.125-143
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    • 2024
  • Korean dramas, commonly referred to as Koreanovelas or K-Dramas in the Philippines, have significantly influenced and reshaped Philippine television culture since the early 2000s. Their impact persists in contemporary television programming, reflecting the transnational flow of media texts across borders. As media content transcends geographical boundaries, local media companies have adopted the practice of producing adaptations of foreign television series for their audiences. This paper examines the adaptation of the Koreanovela The World of the Married into the Philippine series The Broken Marriage Vow, both of which are adaptations derived from the British show Doctor Foster. Through this comparative analysis, I argue that the process of localizing these television shows to suit the preferences of the target audience serves as a tangible manifestation of transnational adaptation. Particularly in an era of globalization, where entertainment is still a thriving enterprise, thus traversing international borders, this phenomenon demonstrates the evolving nature of television content as it adapts and caters to diverse cultural contexts let alone a profitable means to generate an ailing entertainment industry, especially in the time of the pandemic.

순환골재의 부착 모르타르량이 콘크리트의 특성에 미치는 영향 (Effect of the Amount of Attached Mortar of Recycled Aggregates on the Properties of Concrete)

  • 이원기;최종오;정용욱
    • 한국건설순환자원학회논문집
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    • 제3권2호
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    • pp.132-139
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    • 2015
  • 본 연구는 파쇄처리 순환골재를 사용한 콘크리트의 특성을 검토하기 위하여 순환골재의 흡수율별 단위시멘트량 및 물시멘트비를 변화시켜 콘크리트의 특성에 미치는 영향을 검토하였다. 실험결과 물시멘트비가 높은 저강도 배합에서는 파쇄처리 순환골재를 사용한 콘크리트와 쇄석 콘크리트의 압축강도가 동등한 수준으로 나타나 순환골재의 부착모르타르 영향이 작은 것으로 나타났다. 그러나, 물시멘트비가 낮은 고강도 배합에서는 파쇄처리 순환골재를 사용한 콘크리트가 부착모르타르의 영향으로 쇄석을 사용한 콘크리트보다 약 40%의 압축강도저하를 나타내었다. 한편, 흡수율 7%인 순환골재의 건조수축량은 재령 10주에서 흡수율 1%인 쇄석의 $-310{\times}10^{-6}$보다 2배 증가된 $-700{\times}10^{-6}$을 나타내어 콘크리트용 골재로의 재활용시 건조수축에 대한 검토가 선행되어야 할 것으로 사료된다. 또한 단위시멘트량 $450kg/m^3$인 부배합 콘크리트의 압축강도는 흡수율 3%인 순환골재 사용시 쇄석 사용 콘크리트와 동등하게 나타난 반면, 흡수율 7%인 순환골재를 사용한 경우에는 쇄석 사용 콘크리트에 비해 약 7%정도 낮게 나타났다. 그러나, 단위시멘트량 $350kg/m^3$인 일반배합 콘크리트의 압축강도는 쇄석 사용 콘크리트에 비해 압축강도 저하가 현저하게 나타났다.