• 한국도로학회논문집
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• 제18권3호
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• pp.21-32
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• 2016

PURPOSES : In this paper, the analytical solutions suggested to simulate the behavior of rheological fluids were rigorously re-derived and investigated for fixed conditions to evaluate the applicability for the solutions on a mini-cone slump test of cement paste. The selected solutions with proper boundary conditions can be used as reference solutions to evaluate the performance of numerical simulation approaches, such as the discrete element method. METHODS : The slump, height, and spread radius for the given boundary and yield stress conditions that are determined by five different analytical solutions are compared. RESULTS : The analytical solution based on fluid mechanics for pure shear flow shows similar results to that for intermediate flow at low yield stresses. The fluid mechanics-based analytical solution resulted in a very similar trend to the geometry-based analytical solution. However, it showed a higher slump at high yield stress and lower slump at low yield stress ranges than the geometry-based analytical model. The analytical solution based on the mini-cone geometry was not significantly affected by the yield criteria, such as von Mises and Tresca. CONCLUSIONS : Even though differences among the analytical solutions in terms of slump and spread radius existed, the difference can be considered insignificant when the solutions were used as reference to evaluate the appropriateness of numerical approaches, such as the discrete element method.

• 분석과학
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• 제28권3호
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• pp.160-167
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• 2015

이 연구에서는 화장품 중 사용한도 성분으로 지정되어 있으나 아직 분석방법이 개발되지 않은 살균 보존 성분으로 사용되는 zinc pyrithione (ZnPT)에 대한 분석방법을 개발 확립하기 위한 목적으로 국 내외 자료 및 문헌을 조사하여 분석방법을 설정하였으며, 분석방법의 유효성 확인에 필요한 base matrix 시료의 선정을 위해 대상성분들의 사용량 및 사용제품들에 대한 자료를 조사하였다. Base matrix 시료를 선정·제조한 후 분석방법 유효성 확인 절차에 따라 각 대상성분들에 대한 분석방법의 유효성을 확인하였으며 실험실간 분석방법의 유효성 확인 수행을 통해 개발된 분석방법을 검증하여 확립하였다. 최종적으로 실제 시중 유통 화장품을 대상으로 개발된 분석방법을 적용하여 분석방법의 적합성을 검증하였다. 이 연구를 통해 개발된 분석방법을 '화장품 중 배합한도 성분 분석법 가이드라인'으로 제시함으로서 국내 시장 유통화장품의 검정에 활용되어 품질의 향상 및 국민 보건 안전성이 증진될 것이며 국내 화장품 산업의 국제 경쟁력 강화로 인해 수출 증대에 기여할 것으로 기대된다.

• Journal of Pharmaceutical Investigation
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• 제40권1호
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• pp.59-61
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• 2010

This study was carried out to establish standard analytical method of Hippocastani Semen extract. Each standard analytical methods were covered for exact and efficient analytical method. Consequently, analytical method of Deutsches Arzneibuch has been adopted for Hippocastani Semen extract. Analytical methods established in this study could be applied to a reasonable and unified quality control of Hippocastani Semen extract.

• Ocean Systems Engineering
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• 제3권2호
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• pp.79-95
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• 2013

Suction anchors are widely adopted in mooring systems. However there are still challenges in predicting the failure mode and ultimate pullout capacity of the anchor. Previously published methods for predicting the inclined pullout capacity of suction anchors are mainly based on experimental data or the FEM analysis. In the present work, an analytical method that is capable of predicting the failure mode and ultimate pullout capacity of the suction anchor in clay under inclined loading is developed. This method is based on a rational mechanical model for suction anchors and the knowledge of the mechanism that the anchor fails in seabed soils. In order to examine the analytical model, the failure angle and pullout capacity of suction anchors from FEM simulation, numerical solution and laboratory tests in uniform and linear cohesive soils are employed to compare with the theoretical predictions and the agreement is satisfactory. An analytical method that can evaluate the optimal position of the attachment point is also proposed in the present study. The present work proves that the failure mode and pullout capacity of suction anchors can be reasonably determined by the developed analytical method.

• 한국안전학회지
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• 제27권5호
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• pp.99-104
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• 2012

A turnelling work beneath roadways or railways in use is unsafe and dangerous. A turnelling method should be analytically and experimentally studied to verify stability and safety of excavating works by construction step. The conventionally analytical method was ineffective in computational time and cost, so the new analytical method named homogenuity method, was developed and verified compared with analytical results. That method was applied to parameterly study the effect of distance of steel supports and overburdening height of soil. It showed that the homogenuity method was very practical and effective in step-by-step analysis considering construction sequences. A measuring device was set at the construction field and mechanical behavior was monitored during construction. Measuring values are larger than analytical values because impact of inserting steel pipes, lowering level of underground water and vibration of passing vehicles affected soil density during construction, but those values were within allowable limits.

• 한국연초학회지
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• 제27권2호
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• pp.207-211
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• 2005

This study was carried out to develop calibration equation of total volatile bases of tobacco leaf using near infrared spectroscopy(NIRS). Burley, imported flue-cured and oriental leaf tobacco samples were collected in 2005 crop year. Calibration equation was developed by modified partial least square method. The standard error of calibration and $R^2$ between traditional analytical method and NIRS analytical method were $0.038\%$, 0.983 for burley and $0.027\%$, 0.986 for imported flue-cured and oriental leaf, respectively. The standard error of performance and $R^2$ between traditional analytical method and NIRS analytical method were $0.048\%$, 0.940 for burley and $0.024\%$, 0.986 for imported flue-cured and oriental leaf, respectively. From these results, the NIRS analytical method seems to be applicable in analyzing total volatile bases of tobacco.

• 한국구조물진단유지관리공학회 논문집
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• 제3권4호
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• pp.155-162
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• 1999

This paper presents a generation of analytical fragility curves for bridge. The analytical fragility curves are constructed on the basis of nonlinear dynamic analysis. Two-parameter lognormal distribution functions are used to represent the fragility curves with the parameters estimated by the maximum likelihood method. To demonstrate the development of analytical fragility curves, two of representative bridges with a precast prestressed continuous deck in the Memphis. Tennessee area are used.

• 한국수학사학회지
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• 제20권1호
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• pp.17-32
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• 2007

이 논문에서는 19세기 초에 영국 케임브리지 대학에서 나타났던 '해석학회'를 중심으로 18세기 후반에서 19세기 전반까지의 영국 수학계의 상황을 살펴볼 것이다. 이를 통해 흔히 매우 새롭고 혁신적인 사건으로 언급되는 해석학회의 등장이 19세기 이전 영국 수학계의 꾸준한 개혁 노력들이 축적된 결과 나타날 수 있었음을 보일 것이다. 그 결과 해석학회의 역할과 의의에 대해 새롭게 이해할 수 있게 될 것이다. 또한 이후 영국에서 해석적 방식이 받아들여졌던 과정과 그 경로를 통해 새로운 해석적 방식이 당시 영국의 독특한 지적, 사회적 상황 속에서 대륙과는 다른 방식으로 발전했던 과정을 이해할 수 있을 것이다.

• 분석과학
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• 제21권3호
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• pp.174-182
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• 2008

본 연구에서는 PCBs 함유 폐기물의 적정관리방안을 마련하기 위하여 우리나라의 폐기물공정시험방법에서 제시하고 있는 액상폐기물 중 PCBs 분석방법을 토대로 시간 및 비용을 효과적으로 보다 신속하게 분석하는 방법을 제시하고자, 추출 및 전처리방법, 칼럼정제방법, 분석용 칼럼 조건, 기기분석 조건 및 정량방법을 개발하였다. 분석방법을 검토한 결과 분석시간을 폐기물공정시험방법의 분석시간의 2/3정도로 단축시켰고, 검출한계는 0.5 mg/L이었다. 또한, 제안된 신속분석방법을 PCBs 함유 절연유에 적용하였을 경우 규제기준(2.0 mg/L) 부근인 2.35 mg/L에서 과소평가되는 경향이 나타났으며, 이 시험법을 사용하였을 때 PCBs 함유 폐기물의 부적정하게 평가되는 것을 막기 위해 적용 농도범위를 소수첫째자리에서 반올림하여 최소자리수를 일의자리 즉 1 mg/L 이하인 경우(0.5~1.4 mg/L)로 제한하는 것이 바람직한 것으로 나타났다.

• 한국포장학회지
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• 제10권1호
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• pp.63-68
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• 2004

The regulations for migration amounts in USA, EU and Korea are investigated to compare the actual overall and specific migration date from plastic food packaging materials. Among the packaging materials regulated in above countries, printing ink solvents on packaging materials is used very widely and sometimes cause off-flavor in the food by migration of residual solvents. Even though migration of the residual solvents dose not generally cause safety problems in the contained food, it certainly can generate off-flavor and finally deteriorate quality of the finished product. Therefore regulation and development of analytical method for amount of residual ink solvents are very important issue in food industry. The headspace analytical method and tenax method for residual ink solvent on food packaging materials were evaluated from the accuracy, precise, swiftness and convenience of viewpoint. Headspace analytical method was selected and recommended for using in food industry field.