• Title/Summary/Keyword: analytical method

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Review on Analytical Solutions for Slump Flow of Cement Paste (시멘트 페이스트의 슬럼프 유동 모사를 위한 분석적 해의 검토)

  • Yun, Taeyoung
    • International Journal of Highway Engineering
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    • v.18 no.3
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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.

A study on the development of analytical method for zinc pyrithione in cosmetics (화장품 중 zinc pyrithione 분석방법 개발에 대한 연구)

  • Jung, Jung-sul;Bae, Kyeong-mi;Son, Seung-hwan;Park, Jung-woo;Kim, Ji-hyun;Hong, Sung-taeg;Sun, Yle-shik
    • Analytical Science and Technology
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    • v.28 no.3
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    • pp.160-167
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    • 2015
  • This study aims to develop a new analytical method to detect zinc pyrithione, the ingredient of cosmetics appointed as restricted ingredients and used as preservatives.. The analytical method was based on data gathered from the relevant literature. Information about the amounts of these ingredients was researched in order to select the base-matrix materials used to validate the analytical method. After selecting and preparing the base-matrix materials, the analytical method was validated by method validation procedures. The analytical method was verified first by inter-laboratory validation and then through analyzing the cosmetics sold in the market. Based on the results of this study, guidelines are proposed for the analysis of restricted ingredients in cosmetics, which will provide a method to test the cosmetics circulating in the Korean market. The use of the proposed guidelines will increase the quality of the cosmetics as well as the safety of human health, which will enhance the competitiveness of the Korean cosmetics industry and lead to an increase in the exportation of cosmetics.

Standardization of Hippocastani Semen Extract (서양칠엽수종자엑스 기준및시험법 비교 및 규격 설정)

  • Kim, Seung-Hyun;Kim, Dae-Hyun;Park, Jin-Ho;Cho, Chang-Hee;Lee, Jong-Pill;Kang, Shin-Jung;Lee, Mi-Na;Sung, Sang-Hyun
    • Journal of Pharmaceutical Investigation
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    • v.40 no.1
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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.

Analytical study of the failure mode and pullout capacity of suction anchors in clay

  • Liu, Haixiao;Wang, Chen;Zhao, Yanbing
    • Ocean Systems Engineering
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    • v.3 no.2
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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.

An Analytical and Experimental Study on the Mechanical Behavior of Excavating Turnels beneath the Roadway (공용중 도로하부의 굴착터널 해석 및 계측 연구)

  • Chung, Kuang-Mo;Bang, Myung-Seok
    • Journal of the Korean Society of Safety
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    • v.27 no.5
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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.

Determination of Total Volatile Bases of Tobacco Using Near Infrared Spectroscopy (근외적 분광분석법을 이용한 담배 중 전휘발성염기 분석)

  • Kim Yong-Ok;Jang Gi-Chul;Lee Chul-Hee;Chung Han-Joo
    • Journal of the Korean Society of Tobacco Science
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    • v.27 no.2
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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.

Analytical Fragility Curves for Bridge (교량의 해석적 손상도 곡선)

  • Lee, Jong-Heon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.3 no.4
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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.

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Introduction of Analytical Method to Britain and British Mathematical Development in Nineteenth Century (19세기 초 영국의 해석적 방식의 도입과 이후 영국 수학의 발전 : 19세기 초 케임브리지 대학의 '해석학회'의 의의와 그 한계)

  • Cho, Su-Nam
    • Journal for History of Mathematics
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    • v.20 no.1
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    • pp.17-32
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    • 2007
  • In this paper, I review the origins, activities, and influences on the future mathematical development of the Analytical Society of Cambridge. The story of the late 18th century Scotland mathematicians and the early 19th century Cambridge mathematician such as Woodhouse, and the Analytical Society's history show that the Analytical Society wasn't a completely new and reformative meeting. This article reveals that the new analytical studies developed characteristically in Britain's specific intellectual and social context of the late 18th century and the early 19th century.

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Rapid analytical method of the polychlorinated biphenyls in PCBs containing liquid wastes (PCBs 함유 액상폐기물의 신속분석방법 고찰)

  • Shin, Sun-Kyoung;Jeon, Tae Wan;Yoon, Jeong-Ki;Kim, Tae-Seung;Oh, Gi Jong;Kim, Young Shik;Kim, Kyoung Soo
    • Analytical Science and Technology
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    • v.21 no.3
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    • pp.174-182
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    • 2008
  • The study on the development of rapid analytical method of PCBs containing waste was performed by considering the extraction, column cleanup process, analytical condition and so on. In the established method, new sample clean-up procedure, new quantification peaks and temperature program were introduced. Method detection limit of the method was 0.5 mg/L, and the method could save the total run time to 2/3, therefore save the analysis cost, The new rapid analytical method of transformer oil was suggested to the waste official test method.

Comparison of analytical method of headspace and tenax analysis for residue of solvent amounts on plastic packaging materials (Headspace 방법과 tenax 방법을 이용한 잔존 용제 분석 방법의 비교)

  • An, Duek-Jun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.10 no.1
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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.

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