• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.223-227
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• 2008

Advanced glycation end products (AGEs) contribute to the progression of micro and macrovsacular complication of diabetes and therefore present a promising target for therapeutic agents. In this study, 40 Korean herbal medicines have been investigated with an in vitro evaluation system using AGEs inhibitory activity. Of these, 21 herbal medicines $(IC_{50}<50{\mu}g/ml)$ exhibited an inhibitory activity against AGEs formation compared with anminoguanidine $(IC_{50}=72.12{\mu}g/ml)$. Particularly, 7 herbal medicines, Actinidia arguta (root and stem), Crataegus pinnatifida (twig), Camellia japonica (whole), Kalopanax pictus (bark), Lagerstroemia indica (leaf-stem), Reynoutria sachalinensis (root) showed more potent inhibitory activity (approximately 3-10 fold) than the positive control aminoguanidine.

• The Journal of the Petrological Society of Korea
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• v.4 no.2
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• pp.178-184
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• 1995

The K-Ar ages of biotites, obtained from thirteen pelitic schists in the Jeungpyeong-Deokpyeong area, central Ogcheon metamorphic belt, range from 89 Ma to 213 Ma except for one specimen. These K-Ar ages systematically decrease as the distance between the analyzed specimen and the Jurassic or Creataceous granite decreases. The K-Ar ages of b~otites adjacent to the Jurassic and Cretaceous granites are 166 Ma and 89 Ma, respectively. Thus, the biotite ages are interpreted to result from the partial or complete resetting by thermal activities in association with the intrusion of Mesozoic granites, following the regional-thermal metamorphism at Late Triassic to Early Jurassic times.

• Journal of the Korean Society of Costume
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• v.54 no.4
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• pp.27-40
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• 2004

In this thesis, the connectivity between the military culture in the Middle Ages and costumes by researching the effect on the clothing in the Middle Ages of the culture of knight from the 11th century to middle of the 15th century was tried to be recognized. The culture of knight was widely divided into 4 articles - Chivalry, Tournamemt, The equipment of knight, Heraldry - and then researched. The conclusion after researching the influence of the culture of knight upon the clothing in the Middle Age in the above is as follows. Regarding the clothing, the military culture such as the crusader war, armor, and heraldry was popularized over the entire Middle Ages as the military-look style, and regarding the ornament the result of the crusader war caused the introduction of the Eastern civilization and development of the commerce and industry, and also trade, and consequently the ornament became luxurious. Regarding the footwear, when seeing the Gothic shoes, it can be found that it is similar with the knight's shoes made of the metal. As seen in the above, it can be recognized that the culture of knight caused the huge influence upon the whole politics, culture, and society in the Middle Ages as well as upon the costumes.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.1
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• pp.1-5
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• 2006

In this study, we researched the near addition of presbyopia by the amplitude accommodation method for 40~65ages. The major findings was as follows: 1. The add power was ranged from +0.50Dptr to +3.50Dptr. 2. Add power, +1.50Dptr${\geq}$Add power${\geq}$0.50Dptr was measured in 40~44ages. 3. Add power, +2.00Dptr${\geq}$Add power${\geq}$1.00Dptr was measured in 45~50ages. 4. Add power, +3.00Dptr${\geq}$Add power${\geq}$1.50Dptr was measured in 51~55ages. 5. Add power, +3.50Dptr${\geq}$Add power${\geq}$2.50Dptr was measured in 56~65ages. 6. They put on their glasses for near purpose in 75%.

• YAKHAK HOEJI
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• v.29 no.6
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• pp.367-374
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• 1985

The age-related changes of monoamine contents and monoamine oxidase (MAO) activities in the whole brain and blood pressures were measured and compared every week during the ages of 5 weeks to 12 weeks in two types of animals; (1) spontaneously hypertensive rats (SHR) and (2) normotensive Sprague-Dawley rats (NR). Blood pressures in SHR began to rise at the ages of 7 or 8 weeks and were significantly higher thereafter than in NR. Abnormally low MAO activities in the brain of SHR were detected from the ages of 8 weeks. Comparisons were also made between brain monoamine-norepinephrine, dopamine and 5-hydroxytrytamine contents of SHR and those of NR at the same ages throughout the test period. In SHR, none of those monoamine values was consistently higher or lower than in NR during the test period. Protein contents of the brain between SHR and NR were not significantly different at any ages. These observations suggest that the abnormally low MAO activities in SHR brain may be one of the underlying neurological factors for the susceptibilities to hypertension and the deficit of MAO activities may be due to the changes in properties rather than in amount of this enzyme.

• Structural Engineering and Mechanics
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• v.69 no.1
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• pp.33-42
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• 2019

Thermal cracks are cracks that commonly form at early ages in mass concrete. During the concrete pouring process, the elastic modulus changes continuously. This requires the time domain to be divided into several steps in order to solve for the temperature, stress, and displacement of the concrete. Numerical simulations of thermal crack propagation in concrete are more difficult at early ages. To solve this problem, this study divides crack propagation in concrete at early ages into two cases: the case in which cracks do not propagate but the elastic modulus of the concrete changes and the case in which cracks propagate at a certain time. This paper provides computational models for these two cases by integrating the characteristics of the extended finite element algorithm, compiles the corresponding computational programs, and verifies the accuracy of the proposed model using numerical comparisons. The model presented in this paper has the advantages of high computational accuracy and stable results in resolving thermal cracking and its propagation in concrete at early ages.

• Journal of The Geomorphological Association of Korea
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• v.25 no.4
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• pp.49-62
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• 2018

This study tries to reveal uplift rates inferred from relative and absolute ages on coastal terrace in the West and South Coasts of South Korea. Uplift rate from relative ages on Pleistocene coastal terrace in the West Coast rangesfrom approximately 0.059 to 0.282 m/ky, while a range of approximately 0.020~0.385 m/ky is calculated from the South Coast, suggesting that the South Coast shows higher rate than the West Coast. Based on absolute ages on coastal terrace during MIS 5 in the South Coast, on the other hand, the uplift rates 1 and 4 have ranges of approximately 0.042~0.062 m/ky and 0.051~0.087 m/ky, respectively, indicating that uplift rate in the South Coast is one-third to one-fourth to that in the East Coast. No research on absolute ages in West Coast terrace and lack of relative and absolute ages in the West and South Coasts are considered as the limit in this study.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.397-400
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• 2002

The mechanical properties of concrete such as modulus of elasticity, bond strength and shear strength are proportional to square root of compressive strength. And compressive strength of concrete is developed rapidly at early ages. Thus the relationship between compressive strength and its mechanical properties should be verified because the mechanical properties of early age concrete and hardened concrete are different. In this study, to predict the concrete slab deflection at early ages, modulus of elasticity and effective moment of inertia(Ie) are observed and compared with experimental results.

• Publications of The Korean Astronomical Society
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• v.25 no.3
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• pp.83-90
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• 2010

I briefly review what has been learned from determinations of mean stellar ages and abundances from integrated light studies of early-type galaxies, and discuss some new questions posed by recent data. A short discussion of spectroscopic ages is presented, but the main focus of this review is on the abundances of Fe, Mg, Ca, N, and C, obtained from comparisons of measurements taken in integrated spectra of galaxies with predictions from stellar population synthesis models.

• Journal for History of Mathematics
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• v.12 no.2
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• pp.119-133
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• 1999

In this paper, we consider the abstraction of mathematics and arts. In particular, we compare cave arts of Palaeolith stone ages with those of Neolith stone ages and analyze paintings of a child. After the Middle ages, in Renaissance period the new technique, perspective was introduced by painters for the sake of realistic description. We consider the social background of perspective. In 19th century, European society became familiar with the abstraction of mathematics and arts. And we also study the mathematical concepts and the abstract paintings on the basis of the social backgrounds.