• 제목/요약/키워드: Evaluation criterion

검색결과 964건 처리시간 0.022초

n/m 흐름작업의 Heuristic 기법에 관한 연구 (A Study on the Heuristic Algorithm for n/m Flow- Shop Problem)

  • 이근부
    • 산업경영시스템학회지
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    • 제5권6호
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    • pp.41-48
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    • 1982
  • This paper analyzed md developed flow - shop sequencing heuristic method. The essence of the heuristic approach is in the application of selective routine that reduce the size of a problem. The advantages of this approach are consistency. Speed, endurance and the ability to cope with more data and larger systems than is humanly possible, In recent years many heuristic procedures have been suggested for the flow - shop sequencing problem. Although limited comparisons of these procedures have been made, a full scale test and evaluation have not been reported previously. The maximum flow - time criterion is selected as the evaluation criterion is selected as the evaluation criterion of flow - shop's efficiency. The author evaluated these 3 heuristic method's performance. By the evaluation of the result, we can see that the modified methods produce a shorter maximum flow - time than the original methods.

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질화규소/금속 접합재에 대한 파괴기준 및 파괴거동 (Fracture Criterion and Fracture Behavior in Si3N4/Metal Bonded Joints)

  • 김기성
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1998년도 춘계학술대회 논문집
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    • pp.233-238
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    • 1998
  • Recently, the uses of ceramic/metal bonded joints for structural materials have increased in various engineering fields such as automobiles, heat engines, and so on. A method of strength evaluation focussing on fracture criterion of mixed was investigated in Si3N4/metal bonded joint. Also, Fracture toughness tests of Si3N4/metal bonded joints with an interface crack were carried out and the stress intensity factors of these joints were analyzed by boundary element method. From the results, the fracture criterion and method of strength evaluation by the fracture toughness were proposed in Si3N4/metal bonded joints

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Measures for the Failure Evaluation of SNF Cladding During the Transportation

  • Noh, J.S.;Kim, H.A.;Kim, T.W.
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2018년도 추계학술논문요약집
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    • pp.105-106
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    • 2018
  • It is important to set up a reasonable failure criterion for cladding, because being able to determine the cladding integrity during transportation is essential for the evaluation of SNF transportation system. There are a few of measures which can be used as a failure criterion for cladding subjected to its specific failure mode. Therefore, to select and to use appropriate failure criterion measures, i.e. strain(UE), $K_{IC}$, and CSED would be a key in evaluating the cladding integrity during transportation with every aspects. In order to justify and quantify that criterion properly, various experiments for the mechanical properties of the claddings with different conditions shall be implemented, which data will enable to justify the failure criteria proposed.

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An Evaluation Method of Probability of Elastic-Plastic Fracture by 2-Parameter Criterion

  • Kim, Tae-Sik;Yoon, Han-Yong;Lim, Myung-Hwan;Jung, Ui-Jung
    • Journal of Mechanical Science and Technology
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    • 제18권1호
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    • pp.55-64
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    • 2004
  • Many researchers have made a lot of progress in studying the evaluation of fracture probability of brittle materials. However, studies of fracture probability for elastic-plasticity have not been made yet. An evaluation method for fracture probability which is grafted onto a 2-parameter criterion and statistical probability analysis is not only introduced in this study, but also applied to the simple 2-dimensional model and carbon steel piping to vealuate the effect of statistical variables.

공명초음파법을 이용한 세라믹제 페롤의 미소 크랙 평가법 (Evaluation Method of Micro Crack in a Ceramic Ferrule by Resonant Ultrasound Spectroscopy)

  • 양인영
    • 한국공작기계학회논문집
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    • 제15권3호
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    • pp.59-66
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    • 2006
  • In this paper, we suggested an evaluation method of cracks in a ceramic product by resonant ultrasound spectroscopy. For experiment, we manufactured nondestructive measurement system by resonant ultrasound spectroscopy and measured resonance frequencies of acceptable and cracked ferrules. The evaluation criterion of ferrule is based on the comparison of resonance frequencies between acceptable and cracked-ferrule. The criterion value that defined by suggested formula is 2. By using the criterion, it is possible to evaluate both acceptable and cracked-ferrule.

국내 전자상거래 통계정보의 평가와 신뢰성 증진방안에 대한 연구 (A Study on Evaluation and Improving Reliability of Domestic e-Commerce Statistics)

  • 홍기학;이기성;손창균
    • 응용통계연구
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    • 제16권2호
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    • pp.225-237
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    • 2003
  • 본 연구에서는 국내 전자상거래 시장규모의 추정치와 예측치가 각 조사기관별로 차이가 나는 주요 요인을 분석하고, 이를 객관화, 표준화하여 전자상거래 시장규모 추정치에 대해 보다 신뢰성있는 평가기준을 마련하였다. 또한 이러한 평가기준을 적용하여 조사기관이나 연구 단체에서 발표하는 전자상거래 통계의 신뢰성을 보장하도록 하였다.

개별기술 평가모델 개발에 관한 연구 - 기술 이전 .거래 기준 제시를 위한 가치평가를 중심으로 - (A Study on Development of Technology Evaluation Model - Focus on Value Estimation for Presentation in the Transfer of Technology and a Trade Criterion-)

  • 최락인;박종오
    • 한국컴퓨터정보학회논문지
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    • 제5권2호
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    • pp.130-142
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    • 2000
  • 본 연구에서는 기술이전과 매매기준을 제공할 수 있는 차원에서 개별기술의 가치평가 모델을 제시하고자 한다. 개별기술 가치평가는 정부. 정책시행기관. 기업 등에서 시급히 해결해야할 과제로 인식되어야 하며 기술평가방법 수단의 객관화. 기술평가의 전문가 양성ㆍ축적, 기술평가기관의 전문화, 공신력 확보, 기술평가결과의 활용 확대 등 개별기술평가제도의 정착이 필요하다. 또한 기술거래소의 설치 운영이 필수적이라는 사고가 정착되어야 한다.

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GIS와 지구통계학을 이용한 충주호 남부지역의 광역적인 사면안정평가 (Regional Evaluation of Slope Stability by Using GIS and Geostatistics Around the Southern Area of Chungju Lake)

  • 문상기
    • 자원환경지질
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    • 제33권2호
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    • pp.117-128
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    • 2000
  • Regional evaluations of slope stability by the failure criterion and by environmental geological factors were conducted. The failure criterion is the general conditions for plane failure which consider the geometrical conditions between geological discontinuities and topographical slope planes. The factor focused in this condiction is dip and dip direction. Geostatics, named semivariogram was used for establishing structural domains in slope stability evaluation by the failure criterion. The influential range was calculated to 6 km in the case of dip direction of dominant joint set and 7 km in the case of dip of the same dominant joint set. Then applying this failure criterion to the study area produced a slope stability map using the established domains and slopes generated by TIN module of ARC/INFO GIS. This study considered another regional slope stability analysis. 5 failure-driven factors 9the unstable slope map, geology, engineering soil, groundwater, and lineament density) were selected and used as data coverages for regional slope stability evaluation by geoenvironmental factors. These factors were weighted and overlayed in GIS. From the graph of cumulatave area (%) and instability index, finding critical points classified the instability indices. The most unstable slopes are located in the southern area of Mt. Eorae, Dabul-ri, and the eastern area of Junkok-ri in the first area is plane failure. Also, the expected orientations of failure are 59/338 and 86/090 (dip/dip direction).

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농업환경 분야의 미래유망기술 및 전략기술에 관한 우선순위 재설정 (Priority Re-setting for Future Core & Strategic Technologies in Agricultural and Environmental Science)

  • 조근태;주진호;옥용식;신봉철;김지용;이종인
    • 한국환경농학회지
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    • 제27권4호
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    • pp.395-405
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    • 2008
  • The objective of this study was to set priority for future core technologies in agricultural and environmental science using analytic hierarchy process(AHP). Forty-six technologies were derived by specialist meetings. Evaluation criteria, for setting the priority were decided as 'technology', 'marketability', and 'public'. Eighteen specialists in agricultural and environmental science answered to the questionnaire for AHP. As the results, 'technology' was decided as the most important evaluation criterion. The 'Feasibility' in 'technology' criterion, 'Market Growth' in 'marketability' criterion, and 'Impact to other industry' in 'public' criterion were decided as sub-criteria in each criterion. The most important technology was 'Risk assessment of toxic heavy metals and establishment of accreditation criteria for environmentally friendly agricultural products.

An evaluation of the Mantel-Fleiss validity criterion for the Mantel-Haenszel statistic

  • Younghae Chung;Charles S. Davis
    • Communications for Statistical Applications and Methods
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    • 제5권1호
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    • pp.265-275
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    • 1998
  • In testing the partial association between two variables after controlling for the S levels of a third factor, the Mantel and Haenszel (1959) statistic is often used. Since the statistic is based on the asymptotic distribution of the sum X of S hypergeometric variates, a guideline for the minimum requirements for the application of the statistic is useful. Mantel and Fleiss (1980) developed a criterion based on the guideline for the Pearson's $X^2$ statistic. The criterion requires the distance from the expected value to the closer bound of X to be at least five. The Mantel-Fleiss (MF) criterion was studied through a simulation using the hypergeometric sampling scheme. The criterion is not satisfactory. The size of statistic exceeded nominal 0.05 level nearly 1/5 of the cases even when the criteion is met. However, the results show that the statistic is much more unstable and conservative when the criterion is not met.

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