• 한국세라믹학회지
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• 제43권1호
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• pp.4-9
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• 2006

To test the fracture toughness of alumina; a Surface-Crack-in-Flexure (SCF) method, a Single-Edge-Precracked-Beam (SEPB) method and a Single-Edge-V-Notched-Beam (SEVNB) method were used at crosshead rates ranging from 0.005 mm/min to 2 mm/ min and relative humidity ranging from $15\%\;to\;80\%$. The results show that the fracture toughness tested by the SCF method increases with either an increasing loading rate or decreasing relative humidity; in contrast, the toughness by the SEPB method and the SEVNB method does not depend on the loading rate or the relative humidity. Theoretical analysis of the way slow crack growth affects the apparent fracture toughness indicates that the three testing methods have different effects with respect to the loading rate and the relative humidity; moreover, these differences are attributable to differences in the size of the cracks or notches.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1993년도 추계 학술발표 강연 및 논문 개요집
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• pp.52-53
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• 1993

• 영재교육연구
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• 제11권2호
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• pp.59-85
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• 2001

본 연구는 대학부설 과학영재교육센터의 종합적인 평가 기준을 개발하는 데 목적이 있다. 이를 위해서 먼저, 국내 대학부설 과학영재교육센터의 운영 현황을 분석하고 과학영재교육센터 운영에 있어서 시급한 문제점을 도출하였고, 다음으로 ‘특수목적고’와 시·도교육청이 운영하고 있는 ‘과학영재반’과의 차별성을 위한 대학부설 과학영재교육센터의 위상을 정립하기 위한 과학영재교육센터 평가의 기본 방향 및 평가틀을 구안하였다. 이를 바탕으로 과학영재교육센터 평가 영역별 평가 기준 및 평가 방법을 구안하였다. 마지막으로, 이상의 연구 결과를 바탕으로 실제 과학영재교육센터 평가에 적용하기 위한 평가 종류(시기)에 따른 평가 방법과 활용 방안을 정리·제시하였다. 본 연구에서 개발한 과학영재교육센터 평가 기준은 우리나라 대학부설 과학영재교육센터의 효율적인 평가를 위해 유용하게 활용될 수 있을 것으로 기대한다.

• 한국초등수학교육학회지
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• 제7권1호
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• pp.87-94
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• 2003

미국수학교사회(NCTM)는 1989년에 Curriculum and Evaluation Standards for School Mathematics (학교 수학의 교육과정과 평가 규준)를 발표하여 각 국의 수학과 교육과정 및 교수 학습에 영향을 주어 왔고, 2000년에는 그의 개정판 성격을 띤 Principles and Standards for School Mathematics (학교 수학의 원리와 규준)를 내 놓아 기술 공학 등 사회 변화의 조류에 맞는 수학 교육을 위한 지침을 제공하고 있다. 우리나라에서는 이 개정판에 대한 관심이 아직 상대적으로 많지 않아 일선 학교에 있는 교사들에게는 그 구체적인 내용을 접할 기회가 많지 않았다. 본 고에서는 이 개정판에 대한 특징을 살펴보고 우리에게 주는 시사점을 알아보고자 한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.387-388
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• 2012

• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2004년도 제35차 춘계학술대회
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• pp.94-96
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• 2004

• 한국정보시스템학회지:정보시스템연구
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• 제16권3호
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• pp.91-108
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• 2007

To decide a reasonable investment priority of public enterprises, it is required to have an efficient evaluation standard. However, without having a standard, a budget for those enterprises has been allocated. In this research, for the efficient and reasonable budget allocation, it is discussed how to decide investment priority of information and communication enterprises of the government. In order to examine possible alternatives of the investment priority of information and communication enterprises of the government, seventeen enterprises were chosen from the enterprises of Ministry of Information and Communication. Public benefit, economic benefit, technology, politics, and step-up increase of budget were set up as evaluation standards and 16 specific standards were set up as subordinates. A hierarchical decision model was designed and analyzed by using AHP.

• Journal of Magnetics
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• 제6권1호
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• pp.27-30
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• 2001

We present a new procedure to evaluate the residual life of 1Cr-1Mo-0.25V steel from reversible magnetic permeability. The method is based on the existence of first harmonics in the differential magnetization around the coercive force. The apparatus is based on the detection of the voltage induced in a coil using a lock-in amplifier tuned to the frequency of the exciting coil. Results obtained for the first harmonics and Vickers hardness on aged samples show that the peak interval of reversible permeability and Vickers hardness decrease as aging time increases. The correlation between Vickers hardness and the peak interval of the reversible permeability may be used to evaluate the residual life of 1Cr-lMo-0.25V steel, nondestructively.

• 열처리공학회지
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• 제14권5호
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• pp.275-281
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• 2001

To improve the reliability of hardness test results, Rockwell hardness round robin test was carried out for 10 laboratories. The test condition was the same with the ISO(International Standards Organization) standards. Korea Research Institute of Standards and Science(KRISS) supplied the hardness standard blocks and an indenter to laboratories for the measurement. The participating laboratories measured hardness of the specified areas on the blocks for 6 times with their own indenter as well as common indenter, respectively, and reported the results to KRISS. The result showed that quite large amount of the differences came from the indenter and it is necessary to change indenter with better quality for improved reliability in hardness measurement.

• International Journal of Stem Cells
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• 제17권2호
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• pp.182-193
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• 2024

To address the limitations of animal testing, scientific research is increasingly focused on developing alternative testing methods. These alternative tests utilize cells or tissues derived from animals or humans for in vitro testing, as well as artificial tissues and organoids. In western countries, animal testing for cosmetics has been banned, leading to the adoption of artificial skin for toxicity evaluation, such as skin corrosion and irritation assessments. Standard guidelines for skin organoid technology becomes necessary to ensure consistent data and evaluation in replacing animal testing with in vitro methods. These guidelines encompass aspects such as cell sourcing, culture techniques, quality requirements and assessment, storage and preservation, and organoid-based assays.