• 한국안전학회지
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• 제17권4호
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• pp.19-24
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• 2002

User-friendly-web-based database system for searching creep property data was developed. This system includes about 38000 creep data for 270 different materials including low carbon steel, stainless steel and alloy steel. Data on creep rupture, creep deformation, creep crack growth and creeping materials can be searched through this system. Retrieved data is displayed in numeric form and also presented in graphical form for visualizing the data. Furthermore, the creep rupture data is designed to be fitted to a regression equation of logarithmic stress using time-temperature parameter(TTP). The degree of the regression equation, orthogonal polynomials, was determined using analysis of variance.

• 열처리공학회지
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• 제15권3호
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• pp.127-135
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• 2002

Shore hardness test was developed in 1906 to overcome the limit of Brinell hardness test. However, the detailed requirements on the tester was not clearly specified except the scale, i.e., 100 HS for high carbon steel and 10 HS for soft brass. As a result, the shore hardness was used for quite long time without well established standards. For the establishment of hardness standards, standard tester, standard procedure, and standard hardness block must be provided. So far the standard of Shore hardness was maintained by correlating Shore hardness scale to Vickers hardness through converting equation. This is the so called converted Shore hardness and it is not the true Shore hardness standard strictly. In this paper, the possibility of establishing Shore hardness standard based on the Shore standard hardness tester is reported.

• 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.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2005년도 하계학술연구발표회 논문개요집
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• pp.200-201
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• 2005

• 분석과학
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• 제18권6호
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• pp.552-558
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• 2005

환경 대기 중에 미량 농도로 존재하는 악취 물질의 측정을 위한 ppm 수준의 다이메틸설파이드($(CH_3)_2S$) 가스 인증표준물질(CRM)을 개발하였다. 이 표준가스는 $(CH_3)_2S$의 농도 수준이 10 umol/mol이고 질소압력이 1500 psi로서, 알루미늄 실린더에 제조되었고, 3년 동안에 0.2% 수준의 안정성을 보였다. 동시에 제조된 표준가스 실린더 4병의 $(CH_3)_2S$ 농도를 가스크로마토그래프-불꽃이온화검출기(GC-FID)로 비교하여 0.4% 수준의 제조 재현성과 0.25%의 중량 및 순도의 표준불확도를 확인하였다. 개발된 $(CH_3)_2S$표준가스의 인증값은 10 umol/mol 수준이었고, 순도, 혼합. 제조, 분석, 흡착성 및 안정성을 모두 고려하여 결정한 인증값의 상대 확장불확도는 1.1%(95%의 신뢰수준, k=2)이었다.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2003년도 somma/kms meeting
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• pp.248-248
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• 2003

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.32.2-32.2
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• 2008

• 분석과학
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• 제21권1호
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• pp.14-19
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• 2008

많은 악취물질 중에 알데하이드는 인간의 호흡기 자극을 유발할 뿐만 아니라 인간의 건강에 상당히 안좋은 영향을 미친다. 알데하이드류의 악취물질은 일반 대기오염물질과 달리 ppt 수준의 매우 극미량에서 악취를 발생하는 성분이 많아 매우 극미량의 측정기술의 필요하다. 또한 대부분 반응성이 크고 안정성이 낮아 표준가스 제조 및 분석이 매우 어려워 정확한 측정이 어렵다. $10{\mu}mol/mol$ 수준의 농도로 제조된 4성분 알데하이드 CRM(MK0731)은 ISO 6142에 의한 중량법으로 제조하였다. $10{\mu}mol/mol$ 알데하이드 표준가스 실린더를 반복 제조하여 각각 GC-FID로 제조의 균질성을 조사하였고, 개발된 알데하이드류 CRM 인증값의 상대 확장불확도는 2.11 %(95%의 신뢰수준, k=2)로 조사되었다.

• 한국정밀공학회지
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• 제28권3호
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• pp.323-329
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• 2011

Certified reference materials (CRMs) have been used to calibrate surface profilers for reliable measurements. In this paper, we present a newly designed step height CRM which has a step height pattern with two different widths and various special patterns for checking radial magnification, distortion of optical viewing systems, etc. Especially, it could be useful for multi-probe inspection instruments in the manufacturing lines. The fabrication was done by conventional optical lithography and dry etching process with optimized conditions. To verify the step height values, a white-light scanning interferometer was used with objective lenses having magnification of $10{\times}$ and $100{\times}$. CRMs with nominal step heights of $0.5\;{\mu}m$, $1\;{\mu}m$, $3\;{\mu}m$, $5\;{\mu}m$, $7\;{\mu}m$, and $10\;{\mu}m$ were fabricated and the uniformity of these CRMs was evaluated to be less than 3 nm ($1{\sigma}$).

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.792-793
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• 2006

In the paper, the influence of different particle size $D:D>125{\mu}m$, $D<50{\mu}m$ and between on magnetic properties of a standardized dielectromagnetic is presented. The tests were taken at frequencies of between 50Hz, and 500Hz. Presented in the paper results provide important materials property data to allow the selection of the most appropriate dielectromagnetic particle size for different applications.