• 제목/요약/키워드: 안전계수(safety factor)

검색결과 357건 처리시간 0.022초

A Study on the activation factor for quality innovation to small and medium enterprises (중소기업의 품질혁신활성화 요인에 관한 연구)

  • Koo, Il-Seob
    • Proceedings of the Safety Management and Science Conference
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    • 대한안전경영과학회 2010년도 춘계학술대회
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    • pp.329-339
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    • 2010
  • 본 연구에서는 중소기업에서 품질혁신활동을 추진할 때 정부와 모기업차원에서 지원이 가능한 요소들에 대해 Kano가 제시한 방법의 설문을 활용하여 조사하였다. 이 조사 결과를 Kano 분석과 함께 Timko가 제시한 고객만족계수를 활용하여 분석하여 품질혁신활동을 지원하는 정부와 모기업, 그리고 추진의 주체인 기업 등에 작용하는 매력적 요인과 일원적 요인, 당연적 요인 등을 밝히고자 하였다.

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A Study on Estimation of Residual Stress in Carburized Spur Gears and Its Effect on the Stress Intensity Factor (침탄치차의 잔류응력추정 및 잔류응력을 고려한 응력확대계수에 관한 연구)

  • 류성기
    • Journal of the Korean Society of Safety
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    • 제12권3호
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    • pp.30-37
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    • 1997
  • This paper deals with the residual stress of carburized spur gears is calculated being on the assumption that the main cause of residual stress is the volume difference between case and core due to the martensitic transformation in cooling. A formula is proposed to estimated the residual stress from the hardness and the amount of retained austenite. The estimated residual stress is close to the stress measured by X-ray method. The estimated residual stress is applied to the analysis of the fracture mechanics of carburized spur gear teeth. The stress intensity factor due to the residual stress is demonstrated. The stress intensity factor is computed by the influence function method, and it is shown that the factor is decreased by the residual stress in Carburized gear tooth.

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Development and validation of Accident Modification Factors of Two-Lane Rural Roadways (지방부 2차로 도로의 사고예측계수 개발 및 검증)

  • Kim, Eung-Cheol;Choe, Eun-Jin;Lee, Dong-Min;Kim, Do-Hun
    • Journal of Korean Society of Transportation
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    • 제28권3호
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    • pp.131-143
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    • 2010
  • This study has aimed to develop accident modification factor(AMF) for rural two-lane roadway segments. Accident Modification Factor is a coefficient to assess roadway safety as reflecting characteristics of homogeneous roadway. It estimates accident frequency of roadway segments with developed base model and exposure. We found on items of such factors as crosswalk, driveway density, topography characteristic, land use and median through statistical models and literature review. To develop accident modification factors, we used statistical model methods and analyses of applicability and expert judgement method were practiced to validate it. Although expert judgement for land use item was questionable, most items were rated acceptable. Result of comparative analysis revealed crash frequencies of IHSDM and KHSEM were most similar with actual. However, accident distribution of KHSEM was more proper than IHSDM. Also overall estimated values of RSDS were found to be overestimated.

A Stochastic Analysis in Steam Turbine Blade Steel Using Monte Carlo Simulation (몬테카를로 시뮬레이션을 이용한 증기 터빈블레이드재의 확률론적 해석)

  • Kim, Chul-Su;Jung, Hwa-Young;Kang, Myung-Su;Kim, Jung-Kyu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • 제26권11호
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    • pp.2421-2428
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    • 2002
  • In this study, the failure probability of the degraded LP turbine blade steel was performed using the Monte Carlo simulation to apply variation of applied stress and strength. For this purpose, applied stress under the service condition of steady state was obtained by theoretical stress analysis and the maximum Von-Mises stress was 219MPa. The fatigue strength under rotating-bending load was evaluated by the staircase method. Furthermore, 3-parameter Weibull distribution was found to be most appropriate among assumed distributions when the probabilistic distributions of tensile and fatigue strength were determined by the proposed analysis. The failure probability with various loading conditions was derived from the strength-stress interference model and the characteristic factor of safety was also estimated.

Reliability-Based Load and Resistance Factor Design (신뢰성 이론에 의한 하중 및 저항계수 설계)

  • Son, Seung Yo;Lee, Jong Heon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • 제7권4호
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    • pp.1-12
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    • 1987
  • The Advanced First Order Second Moment(AFOSM) method is commonly used to determine partial safety factors in the development of probability based LRFD code. However, design format using load and resistance factors based on this method may result in different reliability levels from specified ones. Reliability-Conditioned(RC) method recently proposed by Ayyub et al. gives partial safety factors which do not affect the target reliability level as specified. However, this method has some numerical difficulties and the procedure is not consistent. The proposed RC/AFOSM combined method has not only numerical consistency, but also results in almost constant partial safety factors with respect to various design conditions, and the resulting reliability levels are very close to specified ones.

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Development of Statistical Models for Resistance of Reinforced Concrete Members (철근콘크리트 부재 저항능력의 통계적 모델 개발)

  • Kim, Jee Sang;Kim, Jong Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • 제31권4A호
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    • pp.323-329
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    • 2011
  • Most current design codes of concrete structures adopt the partial safety factor format to assure the proper safety margin or reliability against various limit states as a practical design tool. The safety factors, load and resistance factors and so on, are determined based on the theory of structural reliability, which takes into account the statistical uncertainties of both loads and resistances. The establishment of statistical models for load and resistance should be preceded the application of reliability theory. In this paper, especially the influence of the statistical variations of resistance models, which are described in terms of strength of concrete, strength of reinforcements and sectional dimensions and so on, are examined and the probabilistic models for resistance of reinforced concrete members were developed. The statistical data were collected on local tests and experiments in Korea and the Monte Carlo simulation (MCS) technique was used. The results of this paper may be useful and valuable in calibration of design code in this country.

Optimal Design of Rubble Mound Breakwater Used by Partial Safety Factor Method (부분안전계수를 이용한 경사식 방파제의 최적설계기법)

  • 이동훈;민석진;김성득
    • Journal of Ocean Engineering and Technology
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    • 제17권6호
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    • pp.23-31
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    • 2003
  • As there are so many uncertainties associated with using the determinism analysis method in the design of rubble mound breakwater, it is impossible for a designed construction to provide ultimate stability. First of all, due to the uncertainty of Load and Resistance, a safety level concerning the destruction mode of construction must be given. Then, the optimization design should be processed. After all, we can say that it is a more reasonable design method than the design used by the stability rate. In this study, an established design process is accomplished using Hudson's equation and an economic analysis with the breakwater's section is also conducted. Hudson's equation is compared to Van der Meer's equation. These results are utilized to drop a damage rate, increase the stability of construction, and determine the optimization section of the breakwater.

The Experimental Study for inferring the Safety-Factor of the Limit of Span-Deflection in Standard Specifications for Highway Bridges for Setting the Standard of the Measurement Criteria in RC Girder (철근콘크리트 거더의 관리기준치 설정을 위한 도로교설계기준 처짐 제한치의 안전계수 추정에 관한 실험적 연구)

  • Joo, Bong-Chul;Park, Ki-Tae;Hwang, Yoon-Koog;Lee, Woo-Sang
    • Journal of the Korea institute for structural maintenance and inspection
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    • 제13권1호통권53호
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    • pp.145-151
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    • 2009
  • The span deflection among the monitoring items of bridge measurement system in real time is representative behaviour and important index of superstructure condition. the limit of span deflection in Standard Specifications for Highway Bridge in Korea has been applied to the method that is making the management-criteria for span deflection in bridge measurement system. But the limit concern mainly serviceability of divers. So it is difficult to find the safety factor of the limit from the viewpoint of bridge safety. This study estimated the safety factor of the limit of span-deflection in Standard Specifications for Highway Bridge in Korea from the viewpoint of bridge safety by the indoor structural test.

Propose new product development process including using of Kano's attractive factor and Timko's customer satisfaction index (Kano 품질특성 및 Timko 고객만족 계수를 이용한 신제품 개발 프로세스 제안)

  • Park, Roh-Gook;Ree, Sang-Bok
    • Journal of the Korea Safety Management & Science
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    • 제11권4호
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    • pp.237-246
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    • 2009
  • In this paper, we propose development of new products including the proposed process of at the customer's requirements. The success of new product development depends on customer satisfaction in the marketplace. Existing product development process, including the customer's interest was weak. In this paper, we propose development of new products which include Kano's attractive quality factor method and Timko's customer satisfaction index method. Also we verified new medical treatment of incontinence-nency which is applied to the proposed process.

Propose new product development process including using of Kano's attractive factor and Timko's customer satisfaction index (신제품 개발 프로세스 사례 연구 -Kano 품질특성 및 고객만족 계수를 이용-)

  • Park, No-Guk;Lee, Sang-Bok
    • Proceedings of the Safety Management and Science Conference
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    • 대한안전경영과학회 2009년도 추계학술대회
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    • pp.83-97
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    • 2009
  • In this paper, we propose development of new products including the proposed process of at the customer's requirements. The success of new product development depends on customer satisfaction in the marketplace. Existing product development process, including the customer's interest was weak. In this paper, we propose development of new products which include Kano's attractive quality factor method and Timko's customer satisfaction index method. Also we verified new medical treatment of incontinence-nency which is applied to the proposed process.

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