• 제목/요약/키워드: Safety Estimation

검색결과 1,651건 처리시간 0.032초

ON COMPARISON OF PERFORMANCES OF SYNTHETIC AND NON-SYNTHETIC GENERALIZED REGRESSION ESTIMATIONS FOR ESTIMATING LOCALIZED ELEMENTS

  • SARA AMITAVA
    • Journal of the Korean Statistical Society
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    • 제34권1호
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    • pp.73-83
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    • 2005
  • Thompson's (1990) adaptive cluster sampling is a promising sampling technique to ensure effective representation of rare or localized population units in the sample. We consider the problem of simultaneous estimation of the numbers of earners through a number of rural unorganized industries of which some are concentrated in specific geographic locations and demonstrate how the performance of a conventional Rao-Hartley-Cochran (RHC, 1962) estimator can be improved upon by using auxiliary information in the form of generalized regression (greg) estimators and then how further improvements are also possible to achieve by adopting adaptive cluster sampling.

강봉 맞대기 용접재의 피로 특성 (Characteristics of Fatigue Strength in Butt-Welded Steel Rods)

  • 정재근;오병덕;이용복
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2007년 추계학술발표대회 개요집
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    • pp.257-259
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    • 2007
  • For this study, SM45C steel rods using generally for power transmission shafts and machine components was selected and welded by Butt-GMAW method. and then it was studied about estimation of fatigue strength and the region of infinite life. From this result, it is demanded that the stress for safety design of machine components using SM45C butt-welded steel rods must be selected in the region of the lowest infinite life of heat affected zone.

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3D-ESPI 시스템을 이용하여 결정된 응력집중계수가 피로수명에 미치는 영향에 관한 연구

  • 김성찬
    • 선박안전
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    • 제12권
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    • pp.36-43
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    • 2003
  • Fatigue life estimation by the theoretical stress concentration factors are, in general, considerably different from test results. And in calculating stress concentration factor, it is very difficult to consider actual geometry and material property which are the notch shapes, imperfections or defects of materials such as porosities inclusions and casting defects, etc. Therefore, the paper deals with the experimental method to find out the more exact stress concentration factors by measuring the strain distributions on each specimen by 3D-ESPI(Electronic Speckle Pattern Interferometry) System. Then the fatigue lives are compared between theoretical calculations using stress concentration factors determined by 3D-ESPI system and fatigue test results

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트러스의 구조손상추정을 위한 진동모드민감도의 패턴인식 (Pattern Recognition of modal Sensitivity for Structural Damage Identification of Truss Structure)

  • 류연선
    • 한국해양공학회지
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    • 제14권1호
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    • pp.80-87
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    • 2000
  • Despite many combined research efforts outstanding needs exist to develop robust safety-estimation methods for large complex structures. This paper presents a practical damage identification scheme which can be applied to truss structures using only limited modal responses. firstly a theory of pattern recognition (PR) is described. Secondly existing damage-detection algorithms are outlined and a newly-derived algorithms for truss structures. Finally the feasibility of the proposed scheme is evaluated using numerical examples of plane truss structures.

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유닛모듈 운반하중에 관한 확률분포 모델 추정 (Estimation of the Probability Distribution Model on the Load of Transport of the Unit Module)

  • 박남천;김균태;김석
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2014년도 추계 학술논문 발표대회
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    • pp.220-221
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    • 2014
  • Recently It has been required the research for the load of transport of the unit module to secure the safety of the transport locking device. So the purpose of this study is to analyze the probability distribution of the load of transport of unit modular when transporting unit modular by vehicle.

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한국형고속열차의 가속도계를 이용한 궤도 불규칙도 검측 (Measurement of Rail Irregularity using acceleration values acquired from the High Speed Rolling stock 350 experimental (HSR-350x))

  • 김영모;김진우;박찬경;박태원
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.1264-1269
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    • 2006
  • Measurement and estimation of rail irregularity is an important factor to concern travelling safety of train. Now a day, rail irregularity have been measured by EM120 and ROGER 1000K imported from MERMAC Co. Italy and making researches actively in Korea. This paper mainly consider to find correlation between acceleration value of wheel axle in HSR350x and rail irregularity value measured by EM120.

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교류전기철도 보호특성 해석 및 고장점표정 시뮬레이션 (The Analysis of Protection -Characteristics and Fault-Locator Simulation on the Electrical Railway)

  • 창상훈;이장무
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 1998년도 추계학술대회 논문집
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    • pp.262-269
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    • 1998
  • In case the fault occurs in AC power supply network, protective relaying system must selectively detect line-to-line/ground fault and immediately cut off the power flow into the fault location for guaranteeing the safety of people, electric vehicle and ground installation etc. It is the most important point in power system operation to minimize the fault duration by rapid trip scheme and accurate estimation of the fault location. In this paper, we analyze the load characteristics of each vehicle, perform the fault analysis of AC power supply network using AT current-ratio method. The result shows its usefulness.

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