• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.1-8
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• 2024

In this study, the influence of thermal aging on structural integrity is investigated for Gr. 91 steel. A commercial grade Gr. 91 steel is used for the virgin material, and service-exposed Gr. 91 steel is sampled from a steam pipe of a super critical plant. Time versus creep strain curves are obtained through creep tests with various stress levels at 600 ℃ for the virgin and service-exposed Gr. 91 steels, respectively. Based on the creep test results, the improved Omega model is characterized for describing the total creep strain curve for both Gr. 91 steels. The proposed parameters for creep deformation model are used for predicting the steady-state creep strain rate, creep rupture curve, and stress relaxation. Creep-fatigue damage is evaluated for the intermediate heat exchanger (IHX) in a large-scale sodium test facility of STELLA-2 by using creep deformation model with proposed creep parameters and creep rupture curve for both Gr. 91 steels. Based on the comparison results of creep fatigue damage for the virgin and service-exposed Gr. 91 steels, the thermal aging effect has been shown to be significant.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6073-6076
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• 2012

Discovery of anticancer drugs that kill or disable tumor cells in the presence of normal cells without undue toxicity is a potential challenge for therapeutic care. Several papers in the literature have emphasized the potential implications of marine products such as seaweeds which exhibit antitumor activity. Study attempts to screen the antitumor effect of Sargassum sp, against chosen cell lines such as MCF-7 (Breast cancer) and Hep-2 (Liver Cancer). Ethanol extract of Sargassum sp. was concentrated using a Soxhlet apparatus and dissolved in DMSO. In vitro cytotoxic activity of Sargassum sp at various concentrations ($100{\mu}g/ml-300{\mu}g/ml$) screened for antitumor effect against the chosen cell lines using MTT assay (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a yellow tetrazole). The study documented that the percentage of cell viability has been reduced with increased concentration, as evidenced by cell death. Sargassum sp extract shows potential cytotoxic activity ($P{\leq}0.05$) with $IC_{50}$ of $200{\mu}g/ml$ and $250{\mu}g/ml$ against Hep-2 and MCF-7 cell lines respectively. The ethanol fraction of Sargassum sp induced cell shrinkage, cell membrane blebbing and formation of apoptotic bodies with evidence of bioactive components as profound influencing factors for anti-tumor effects. Further research need to be explored for the successful application of Sargassum sp as a potent therapeutic tool against cancer.

• Journal of the Korean Society of Fashion and Beauty
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• v.2 no.1 s.1
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• pp.21-33
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• 2004

The main focus of this study is to provide the interrelation about the defining fashion model image by the fashion trend since 1960. This is expressed as follows, First, in the 60s'; 1) Image of innocent dolly style, Jean Shrimpton 2) Image of sexual style, Celia Hammond 3) Image of art style with charicteristic mask, Peggy Moffitt 4) Image of immature boyish style, Twiggy. Second, in the 70s'; 1) Image of natural and intelligent style, Larun Hutton 2) Image of exotic style with black beauty, Imman 3) Image of graceful and sexal style, Veruschka 4) Image of glamour and sexual style, Jerry Hall. Third, in the 80s'; 1) Image of unisexual style with power, Grace Jones 2) Image of graceful and noble style, In`es de la Fressange 3) Image of healthy and sexy style, Christie Brinkley 4) Image of sexy style with good sense, super model. And fourth, in the 90s' and now; 1) Image of glamour sexual style with self-consciousness, Claudia Shiffer 2) Image of graceful style with dignity, Christy Turlington 3) Image of asexual and androginous style, Stella Tennant), 4)Image of Twiggy style with immature and slender, Kate Moss 5) Image of new glamour style, Giseel Bundchen 6) Image of new style with unique beauty, Amber Vaiietta 7)Image of exotic style, Devon Aoki 8) Extraordinary, image of various style. The result of thir study, fashion models image have played a role in transmitting the style of fashion trend in their relevancy. Anyway it can be said that fashion models imply figurative meanings of the fashion trend.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.37.2-37.2
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• 2021

Turbulence produces the density and velocity fluctuations in molecular clouds, and dense regions within the density fluctuation are the birthplace of stars. Also, turbulence can produce non-thermal pressure against gravity. Thus, turbulence plays a crucial roles in controlling star formation. However, despite many years of study, the detailed relation between turbulence and star formation remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we mapped two star-forming molecular clouds, the Orion A and the ρ Ophiuchus molecular clouds, in six molecular lines (¹³CO 1-0/C¹⁸O 1-0, HCN 1-0/HCO⁺ 1-0, and CS 2-1/N₂H⁺ 1-0) using the TRAO 14-m telescope. We applied the Principal Component Analysis (PCA) to the observed data in two different ways. The first method is analyzing the variation of line intensities in velocity space to evaluate the velocity power spectrum of underlying turbulence. We investigated the relation between the star formation activities and properties of turbulence. The other method is analyzing the variation of the integrated intensities between the molecular lines to find the characteristic correlation between them. We found that the HCN, HCO⁺, and CS lines well correlate with each other in the integral shaped filament in the Orion A cloud, while the HCO⁺ line is anti-correlate with the HCN and CS lines in L1688 of the Ophiuchus cloud.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.42.2-42.2
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• 2019

Turbulence is one of the natural phenomena in molecular clouds. It affects gas density and velocity fluctuation within the molecular clouds and controls the mode and tempo of star formation. However, despite many years of study, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we have fully mapped two star-forming molecular clouds, the Orion A and the Ophiuchus molecular clouds, in 3 sets of lines ($^{13}CO$ J=1-0, $C^{18}O$ J=1-0, HCN J=1-0, $HCO^+$ J=1-0, CS J=2-1, and $N_2H^+$ J=1-0) using the TRAO 14-m telescope. We apply a statistical analysis, Principal Component Analysis (PCA), which can recover an underlying turbulent-power spectrum from an observed P-P-V spectral map. We compare turbulence properties not only between the two clouds, but also between different parts within each cloud. We present the first result of our observation program.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.79.3-80
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• 2017

Molecular clouds are the sites of stellar birth. Turbulence is a natural phenomenon in molecular clouds, which largely determines the density and velocity fields. Additionally turbulent energy dissipation can affect the gas kinetic temperature via shocks. Turbulence thus controls the mode and tempo of star formation. However, despite its important role in star formation, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "Mapping turbulent properties of star-forming molecular clouds down to the sonic scale (PI: Jeong-Eun Lee)", we have been mapping two star-forming clouds, the Orion A and the ${\rho}$ Ophiuchus molecular clouds in 3 sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) using the TRAO 14-m telescope. We apply a Principal Component Analysis (PCA), which is an useful tool to represent turbulent power spectrum. We will present the preliminary results of our TRAO KSP toward two regions: OMC 1-4 in the Orion A cloud, and L1688 in the ${\rho}$ Ophiuchus cloud.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.68.1-68.1
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• 2019

Turbulence plays a crucial role in controlling star formation as it produces density fluctuation as well as non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite a plenty of previous studies, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we mapped the Orion A and the Ophiuchus clouds, in three sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) with a high-velocity resolution (~0.1 km/s) using the TRAO 14-m telescope. The mean Trms for the observed maps are less than 0.25 K, and all these maps show uniform Trms values throughout the observed area. These homogeneous and high signal-to-noise ratio data provide the best chance to probe the nature of turbulence in two different star-forming clouds, the Orion A and Ophiuchus clouds. We present comparisons between the line intensities of different molecular tracers as well as the results of a Principal Component Analysis (PCA).

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.305-313
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• 2006

According to the bone-standard measuring, the length between the elbow and the wrist has the span of 1.25 cheoks whereas it has the span of 1.2 cheoks or 1.2 cheoks today, the breadth of the chest has the span of 9.5 chons whereas it has the span of 8 chons today, and the length from celestial pivot to transverse bone has the span of 6.5 chons whereas it has the span of 5 chons, and the length from free rib region to thigh pivot has the span of 6 chons whereas it has the span of 9 chons today. It is said that all of the acupuncture points are correctly prescribed by the bone-standard measuring irrespective of men and women of all ages, fat and lean, and whether large or small in height. This lies at the root of the selecting acupuncture points. The bone standard in Spiritual Pivot and that in common use at present have a little difference and the bone standard of today is based upon A-B Classic. Spiritual Pivot named as Acupuncture Classic was in good preservation until the mid-eleventh century, but the book lost a lot in contents was the incomplete edition. In the 8th year of the king Cheoljong's reign of the North Song Dynasty in 1093, though the nine-volume Spiritual Pivot drafted from the Goryo Dynasty was published, the book was wanting in consistency. While on the other, I think that A-B Classic which has been in a state of perfection had a great influence on the healers of the day.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.55.5-56
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• 2016

Turbulence plays an important role in molecular clouds. However, the properties of turbulence are poorly understood. In order to study the influence of turbulence in molecular clouds, we need to sample the turbulent properties in the full range of scales down to sonic scale. We mapped the $20^{\prime}{\times}60^{\prime}$ area covering the Orion Molecular Cloud (OMC) 1-4 region in HCN 1-0 and HCO+ 1-0 with Taeduk Radio Astronomy Observatory (TRAO) 14-m telescope as part of the TRAO key science program, "Mapping turbulent properties of star-forming molecular clouds down to the sonic scale (PI: Jeong-Eun Lee)". In addition, we combine our TRAO data with other molecular line maps ($^{13}CO$ 1-0, $C^{18}O$ 1-0, CS 1-0, $N_2H^+$ 1-0) obtained with the Nobeyama Radio Observatory (NRO) 45-m telescope. To analyze these data, we apply statistical methods, the principal component analysis (PCA) and spectral correlation function (SCF), which are known to be useful to study underlying turbulent properties and to quantitatively characterize cloud structure. We will present the preliminary results of observations and analyses.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.66.1-66.1
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• 2018

Turbulence is a phenomenon which largely determines the density and velocity fields in molecular clouds. Turbulence can produce density fluctuation which triggers a gravitational collapse, and it can also produce a non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite many years of study, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "apping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we have mapped two star-forming clouds, the Orion A and the ${\rho}$ Ophiuchus molecular clouds, in 3 sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) using the TRAO 14-m telescope. We aim to map entire clouds with a high-velocity resolution (~0.05 km/s) to compare turbulent properties between two different star-forming environments. We will present the preliminary results using a statistical method, Principal Component Analysis (PCA), that is a useful tool to represent turbulent power spectrum.