• 한국신뢰성학회지:신뢰성응용연구
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• 제6권1호
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• pp.27-36
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• 2006

It is increasingly important to ensure that a given vibration test specification of a particular machinery component is appropriately established by considering its real environmental conditions. Vibration test standards for electrical components are well documented, for example in an IEC 60068 series, while standards for machinery components are rarely found except a few military standards. Thus many vibration tests are performed based on the military standards. However, a test based on these military standards often results in over-testing, and under-testing in some cases due to the different environmental conditions. Also, these standards require an appropriate tailoring that may not be easily accomplished. In this paper, various international and military standards are compared and investigated to obtain test specifications relevant for machinery components. Also appropriate tailoring methods are demonstrated through a case study.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1990년도 봄 학술발표회 논문집
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• pp.20-23
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• 1990

In order to evaluate the difference of testing results in the standards on the compressive strength of various countries, we have compared the testing results of the compressive and flexural strength, one of the most important properties of cement, obtained on the various standards(KS, JIS, BS, ASTM) and the statistical method was used to evaluate the results.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1149-1154
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• 2010

Liquid chromatography/mass spectrometry using isotope dilution method has been established as a primary method for the measurement of cortisol in human serum. Verification of this method was accomplished by the participation in Consultative Committee for Amount of Substance-Metrology in Chemistry (CCQM) pilot study. Two levels of cortisol certified reference materials were prepared and certified by the established method. They were used as sample materials for the proficiency testing. The expanded uncertainty in the measurement of cortisol in human serum was approximately 1.2% at 95% confidence level. The results of the proficiency testing showed a good precision among the participants, but some bias to the certified values. This means that commercial field laboratories should keep traceability chain to SI unit through available reference measurement procedures and/or available reference materials.

• 한국군사과학기술학회지
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• 제4권2호
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• pp.70-83
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• 2001

The required standards for environmental tests for communication and electronic equipment used currently in the army are not standards into which the Korean climate and use environment are taken into consideration. But the environmental testing standards of the U.S. army at the time of its establishment(MIL-STD-810) “A” version has been used without taking into consideration the Korean domestic situation and conditions by simply translating the US standards. Adherence to these standards may limit the ability to supply materials in case of emergency since the increase in the manufacturing costs according to excessively strict standards induces an increase in the acquisition cost of military equipment, unnecessarily high maintenance and repair expenses are consumed, and stocks of parts for the military use have to be retained at all times.

• 비파괴검사학회지
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• 제33권4호
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• pp.349-354
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• 2013

적외선 열화상을 이용한 비파괴검사는 다양한 산업분야로 활용도가 확장중이다. 또한, 적외선 열화상을 이용한 용접부의 비파괴검사도 다양하게 진행중이다. 현재는 전기저항 점용접부의 비파괴검사는 방사선 검사를 주로 진행하고 있다. 본 연구는 광 적외선 열화상 비파괴검사를 이용하여 전기저항 점용접부의 용융부(너깃)의 영역을 측정하였다. 실험결과 펄스 적외선 열화상검사 방법을 활용할 경우 짧은 시간안에 명확한 용융부의 검출이 가능함을 확인하였다.

• 기술표준
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• 통권8호
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• pp.91-102
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• 2002

• 기술표준
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• 통권6호
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• pp.93-106
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• 2002

• 비파괴검사학회지
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• 제14권3호
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• pp.157-171
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• 1994

진공도가 $10^{-11}$ Torr 수준의 초고진공 상태에서 작동되고 실제공간에서 개별원자를 구별할 수 있는 주사형 터널링 현미경을 제작하였다. 주사형 터널링 현미경의 배경 및 작동원리와 제작에 있어서의 제문제점들을 서술하고 흑연결정과 실리콘에 대해서 관찰한 결과를 보고한다.

• Tribology and Lubricants
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• 제11권5호
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• pp.47-54
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• 1995

An advanced liquid lubricants for heat engines has been developed and tested successfully in a prototype engine. The lubricant possesses superior oxidation stability and high temperature stability and is capable of surviving for a minimum of three minutes at 425$^{\circ}$C (800$^{\circ}$C) at the ring zone and maintains stability at an oil sump temperature of 171$^{\circ}$C. The lubricant has been evaluated by the Cummins Engine Co. Out of a field of several dozens of lubricant, six lubricant was selected for a prototype 200 hours endurance testing. The NIST lubricant was one of the two lubricants that successfully finished the endurance testing. This paper describes the key lubricant considerations including oxidation and thermal stability, volatility, deposit control. The engine test conditions and the results will be presented.

• 비파괴검사학회지
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• 제15권3호
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• pp.451-460
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• 1995