• Title/Summary/Keyword: elevated

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Deformation Behavior Analysis of Zr-702 Alloy during ECAP at Elevated Temperature (온간 ECAP 공정에서 Zr-702 합금의 변형거동해석)

  • 이강무;권기환;채수원;권숙인;김명호;황선근
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.877-881
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    • 2002
  • Much research efforts have been made on the equal channel angular pressing(ECAP) which produces ultra-fine grains. In this paper the ECAP processes with Zr-702 alloy at elevated temperature and at room temperature are considered. Both two-dimensional and three-dimensional finite element analyses have been employed to investigate the deformation behaviors of specimen during ECAP process.

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Effects of Ursodeoxycholic Acid on Acute Hepatic Lesion (Ursodeoxycholic acid가 급성 간손상에 미치는 영향)

  • 김강석
    • Journal of Food Hygiene and Safety
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    • v.9 no.2
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    • pp.75-80
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    • 1994
  • The effects of ursodeoxycholic acid (UDCA) were studied on the hepatotoxicity induced by several hepatotoxicants such as carbonte trachloride, thioacetamide and 1-naphthylisothiocyanate in ICR male mice. UDCA (50 mg/kg, 100 mg/kg) decreased the elevated serum bilirubin in carbon tetrachloride intoxicated mice, the elevated serum AST, alkaline phosphatase in thioacetamide intoxicated mice, the elevated serum AST and bilirubin in 1-naphthylisothiocyanate intoxicated mice.

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Assessment of the Stiffness factor of the Separator Plate at the Elevated Temperature (연료전지 분리판의 고온 강성 인자 연구)

  • Kim, J.H.;Woo, D.U.;Lee, S.W.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.10a
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    • pp.296-299
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    • 2007
  • The focus of this study is to estimate the stiffness factor of the separator plate of MCFC (Molten Carbonate Fuel Cell) at the elevated temperature. The process factors affecting the stiffness of the separator plate were chosen to determine the most important factor using the finite element analysis with the Taguchi method. The most influential factor, picked out by the ANOYA, turned out the pitch in the separator plate.

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Spectroscopic Studies on Pu(III) Hydrolysis Under Reducing and Elevated Temperatures Conditions

  • Cho, Hye-Ryun;Kim, Hee Kyung;Jung, Euo Chang;Cha, Wansik
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2017.10a
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    • pp.137-138
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    • 2017
  • The spectroscopic reference data for plutonium at different temperatures are necessary information for the chemical speciation and evaluation of thermodynamic data at elevated temperature. This work is the initial step to extend research activities for understanding the plutonium chemistry in aquatic solutions at high temperature. The hydrolysis of Pu(III) and the solubility of Pu(III) hydroxide at the elevated temperature will be discussed.

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A Basic Study on Fatigue Fracture Model at Elevated Temperatures by the Dimensional Analysis Method (차원해석법에 의한 고온피로 파괴 모델의 기초적 연구)

  • 서창민;김영호;권오헌
    • Journal of Ocean Engineering and Technology
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    • v.6 no.1
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    • pp.105-112
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    • 1992
  • The main purpose of this study is to derive a law of fatigue crack growth rate in the region of elastic or elasto-plastic fracture mechanics at elevated temperatures through the application of dimensional analysis. An equation of elasto-plastic fatigue crack growth rate at elevated temperatures appeared a new Arrhenius type equation containing J-integral range and absolute temperature. The elastic or elasto-plastic crack growth rate equation shows a fairly good agreement with the experimental results for Cr-Mo-V rotor steel and Hastelloy-X alloy in the comparatively wide temperature ranges.

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Experimental studies on the material properties of high-strength bolt connection at elevated temperatures

  • Li, Guo-Qiang;Yin, Ying-Zhi;Li, Ming-Fei
    • Steel and Composite Structures
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    • v.2 no.4
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    • pp.247-258
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    • 2002
  • The high-temperature material properties of steel are very important to the fire resistance analysis of high-strength bolt connections. This paper reports on the results of the experimental studies on the high-temperature properties of 20 MnTiB steel which is widely used in high-strength bolts, and the friction coefficient of 16Mn steel plates at elevated temperature which is a necessary parameter for bolted frictional connection analysis. The test data includes yield strength, limit strength, modulus of elasticity, elongation and expansion coefficient of 20MnTiB steel at elevated temperature, and the friction coefficients between two 16Mn steel plates under elevated temperatures and after cooling. Based on the data from the tests, the mathematical models for predicting the mechanical properties of 20MnTiB steel and friction coefficients of 16Mn steel plates have been established.

Impact of UV Radiation and Elevated Temperature on Growth of Phytoplanktons, P. micans, and S. costatum

  • Lee, Bong-Hun;Park, Heung-Jai;Park, Won-Woo;Kim, Woo-Seong
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.3
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    • pp.197-201
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    • 1999
  • The growth of two phytoplanktons was studied in a natural environment and in the laboratory under artificial radiation conditions in the presence or absence of UV radiation. The effect of an elevated temperature on the two phytoplanktons was also examined. UV radiation resulted in a decrease in the growth of the two phytoplanktons ; P. micans was more affected by UV than S. costatum. Four hours of UV radiation decreased the motility of S. costatum and P. micans by 20% and 40%, respectively. Accordingly, an elevated temperature and UV radiation decreased the growth rate of the two phytoplanktons investigated.

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A Study on Field Measurement and Analysis of Train noise at Elevated Railway in Jeolla Line (전라선 고가교 연변 철도 소음 현장측정 및 분석에 관한 연구)

  • Kim, Byoung-Sam;Won, Chan-Hee;Kim, Dae-Jin
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.629-634
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    • 2001
  • The construction of the elevated railway has led to concerns about the noise from trains, particularly as tracks often pass close to residential dwellings. One specific issue relates to the noise from trains on bridges. The wayside noise for the train was measured to get the basic data that can be used to prepare count measures for solving environmental noise problems. Noise levels were measured simultaneously at three points in various distances from the railroad and at four points classified by floor. In this paper we measure the wayside noise in elevated railway and noise of normal operation compare with operating under train engine idling condition and investigate effect of nearby-building induced by train operation.

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New coefficients to find natural period of elevated tanks considering fluid-structure-soil interaction effects

  • Maedeh, Pouyan Abbasi;Ghanbari, Ali;Wu, Wei
    • Geomechanics and Engineering
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    • v.12 no.6
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    • pp.949-963
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    • 2017
  • The main purpose of the current study is to develop the new coefficients for consideration of soil-structure interaction effects to find the elevated tank natural period. Most of the recommended relations to find the natural period just assumed the fixed base condition of elevated tank systems and the soil effects on the natural period are neglected. Two different analytical systems considering soil-structure- fluid interaction effects are recommended in the current study. Achieved results of natural impulsive and convective period, concluded from mentioned models are compared with the results of a numerical model. Two different sets of new coefficients for impulsive and convective periods are developed. The values of the developed coefficients directly depend to soil stiffness values. Additional results show that the soil stiffness not only has significant effects on natural period but also it is effective on liquid sloshing wave height. Both frequency content and soil stiffness have significant effects on the values of liquid wave height.

Study of Frictional Behavior of AZ31B Mg Alloy at Elevated Temperature (AZ31B 마그네슘 합금의 온간 마찰 특성 연구)

  • Han, S.S.
    • Transactions of Materials Processing
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    • v.27 no.3
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    • pp.160-164
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    • 2018
  • The success of warm forming of Mg alloy sheets is very dependent on its frictional behavior at elevated temperatures. The effects of contact pressure and sliding length on the frictional characteristics of AZ31B Mg alloy sheet were investigated at elevated temperature and at room temperature. The contact pressure range for the friction test was determined through FE analysis of the roof panel which is a candidate for Mg alloy application. According to the experimental results, the frictional behavior of the Mg alloy sheet is equally highly influenced by both sliding length and contact pressure at room temperature. At elevated temperatures, however, the sliding length has a more dominant influence on the frictional characteristics of the Mg alloy sheet than the contact pressure, if the contact pressure is lower than a certain level.