• Journal for History of Mathematics
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• v.16 no.4
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• pp.59-68
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• 2003

Mathematics and arts are reflection of the spirit of the ages, since they have human inner parallel vision. Therefore, in ancient Greek ages, the artists' cannon was actually geometric ratio, golden section. However, in middle ages, the Euclidean Geometry was disappeared according to the Monastic Mathematics, then the art was divided two categories, one was holy Christian arts and the other was secular arts. In this research, we take notice of Renaissance Painting and Perspective Geometry, since Perspective Geometry was influenced by Renaissance notorious painter, Massccio, Leonardo and Raphael, etc. They drew and painted works by mathematical principles, at last, reformed the paradigm of arts. If we can say Euclidean Geometry is tactile geometry, the Perspective Geometry can be called by visual geometry.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.4
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• pp.726-736
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• 2018

This study determined how the upper body shape of elderly women changes with age in order to improve the fit of clothing worn by elderly women. Thirty-nine healthy elderly Japanese women had their body measurements taken by measuring tape and a 3D body line scanner (Hamamatsu Model #C9036-02) from December 2011 to March 2012 at a university in Tokyo. It was found that the shoulder line shortens in women between the ages of 70 and 74, but that the upper arm lengthens in women between the ages of 75 and 79. It was also found that the upper part of the scapular area rolls forward in women between the ages of 70 and 74, and that the point of the back which protrudes the most-the lower scapular area-rolls forward in women between the ages of 75 and 79. The results will be helpful for designing clothes for elderly women as their body shape changes with age.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.337-340
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• 1999

The aim of this study is to predict concrete strengths by method of equivalent ages. The method of equivalent ages is to use Arrhenius equation which indicates the influence of curing temperature on the initial hydration ratio in cement. Experimental factors are in this study. The water-cement ratios of concrete mixtures are 0.60, 0.55, 0.50 and 0.45. The curing temperatures within the four chambers are 30, 20, 10 and 5$^{\circ}C$. The test results showed that equivalent age can be used to predict compressive strength of concrete at early ages.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.215-220
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• 2001

The objective of this study is to examine the fracture characteristics of concrete at early ages such as critical stress intensity factor, critical crack-tip opening displacement, fracture energy based on the concepts of the effective-elastic crack model and the cohesive crack model. A wedge splitting test for Mode I was performed on cubic wedge specimens with a notch at the edge. By varying strength and age, load-crack mouth opening displacement curves were obtained and the results were analyzed by linear elastic fracture mechanics. The results from the test and analysis showed that critical stress intensity factor and fracture energy increased, and critical crack-tip opening displacement decreased with concrete age from 1 day to 28 days. The obtained fracture parameters at early ages may be used as a fracture criterion and an input data for finite element analysis of concrete at early ages.

• The Journal of the Korean dental association
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• v.10 no.12
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• pp.813-816
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• 1972

The authors have observed 207 cases on the results of pulp healing after pulp capping. The results are as follows: 1) We could have success-rate of 70% in 207 cases at the ages from 14 to 59. 2) The success-rate in male is 72.4% in 87 cases, and female is 67.5% in 120 cases. So we observed that success-rate was slightly higher in male than female. 3) In view of age group, it was observed that success-rate was 79% in 129 cases at 30 ages below, 62.5% in 40 cases at 30-40 ages, 47.3% in 38 cases at 40 ages over. So we found that the failure-rate was increased by aging.

• Journal of Oral Medicine and Pain
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• v.13 no.1
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• pp.53-60
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• 1988

The authors have studied the growth and development of mandibular permanent teeth in order to the make basic data that are necessary to determine the forensic age. The 631 subjects whose ages range from 3 years to 18 years were selected to analyze calcification degree of mandibular teeth. The results were as follows: 1. There were significant differences between adjacent ages, except 14-15 years and 17-18 years. 2. In each tooth, these were differences between adjacent ages from 3 years to 10 years, except central incisor and third molars. 3. All teeth were almost completely developed at the age of about 14 years, except second and third molars. 4. In each tooth, there were the widest significances between adjacent ages in premolars.

• Economic and Environmental Geology
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• v.21 no.4
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• pp.349-358
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• 1988

K-Ar ages were determined on gangue and wall rock alteration minerals from twenty metallic mineral deposits in the Gyeonggi Massif. Beryl deposits give the age of 185 Ma, whereas tungsten - molybdenum deposits reveal two different age groups such as 172~156 Ma and 91~86Ma. Lead - zinc deposits and gold - silver deposits yield the ages of 160 Ma and 71~197 Ma, respectively. Mineralization ages for each genetic type of deposits in the Gyeonggi Massif can be summarized as follows; pegmatite deposits, 185 Ma; skarn deposits, 156~160 Ma; hydrothermal deposits, 71~197 Ma. Present results together with data previously reported reveal that rare earths, tungsten-molybdenum, base and precious metal deposits in the Gyeonggi Massif were formed in Jurassic and Cretaceous time with a genetic relationship to the Daebo and Bulguksa felsic igneous activity.

• Natural Product Sciences
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• v.14 no.3
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• pp.192-195
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• 2008

Three known compounds, puerarol (1), pueroside B (2), and ononin (3), were isolated from an EtOAc-soluble fraction of the roots of Pueraria lobata. The isolates (1 - 3) were subjected to an in vitro bioassay to evaluate their inhibitory activity on the formation of advanced glycation end products (AGEs). Puerarol (1) exhibited a remarkable inhibitory activity on AGEs formation with $IC_{50}$ value of $2.05{\pm}0.32{\mu}M$ as compared with positive control, aminoguanidine ($IC_{50}$ value : $905.32{\pm}7.58{\mu}M$).

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1199-1202
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• 2001

The objective of this study is to examine the effect of frost damage immediately after placement on compressive strength of concrete. Obviously frost damage produced under low curing temperature at early ages causes the loss of compressive strength of concrete. In order to find the degrees of the loss of compressive strength, compressive strength tests was peformed at 7 and 28-day ages on concrete specimen with various curing temperature history. The results from the tests showed that the loss of compressive strength relative to concrete cured under isothermal temperature at $20^{\circ}C$ was generally from 20 to 50% for 7-day ages and below 20% for 28 day ages. Considering the serious loss of compressive strength over 50% for some cases, careful attention may be needed to placing of concrete under low atmospheric temperature.

• Ocean and Polar Research
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• v.26 no.1
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• pp.43-50
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• 2004

The diffusion model, which considers diffusion and sorption, is proposed. The FEM program developed on the basis of the diffusion model provides the estimation of chloride concentration according to cyclic humidity and sorption. After the humidity diffusion analysis is carried out, the chloride ion diffusion and sorption analysis are conducted on the basis of the preestimated humidity data in each element. Each element has different analysis variables at different ages and locations. At early ages, the difference between inner and outer relative humidity causes the chloride ion penetration by sorption. As the humidity diffusion reduces the difference with age, the effect of sorption on the chloride ion penetration decreases. By the way, the cyclic humidity increases the effect of sorption on the chloride ion penetration at early ages, and the quantity of chloride ion around steel at later ages. Therefore, the in situ analysis of chloride ion penetration for marine concrete structures must be performed considering the cyclic humidity condition and the long term sorption.