• Restorative Dentistry and Endodontics
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• v.34 no.4
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• pp.333-339
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• 2009

This study was done to determine if there is any difference in microleakage between experimental composite resins, in which various proportions of three component photoinitiators (Camphoroquinone, OPPI, Amine) were included. Four kinds of experimental composite resin were made by mixing 3.2% silanated barium glass (78 wt.%, average size; 1 ${\mu}m$) with each monomer system including variously proportioned photoinitiator systems used for photoinitiating BisGMA/BisEMA/TEGDMA monomer blend (37.5:37.5:25 wt.%). The weight percentage of each component were as follows (in sequence Camphoroquinone, OPPI, Amine): Group A - 0.5%, 0%, 1% / Group B - 2%, 0.2%, 2% / Group C - 0.2%, 1%, 0.2% / Group D - 1%, 1%, 2%. Each composite resin was used as a filling material for round class V cavities (diameter: 2/3 of mesiodistal width; depth: 1.5 mm) made on extracted human premolars and they were polymerized using curing light unit (XL 2500, 3M ESPE) for 40 s with an intensity of 600 mW/$cm^2$. Teeth were thermocycled fivehundred times between $50^{\circ}C$and $550^{\circ}C$for 30s at each temperature. Electrical conductivity (${\mu}A$) was recorded two times (just after thermocycling and after three-month storage in saline solution) by electrochemical method. Microleakage scores of each group according to evaluation time were as follows [Group: at first record / at second record; unit (${\mu}A$)]: A: 3.80 (0.69) / 13.22 (4.48), B: 3.42 (1.33) / 18.84 (5.53), C: 4.18 (2.55) / 28.08 (7.75), D: 4.12 (1.86) / 7.41 (3.41). Just after thermocycling, there was no difference in microleakage between groups, however, group C showed the largest score after three-month storage. Although there seems to be no difference in microleakage between groups just after thermocycling, composite resin with highly concentrated initiation system or classical design (Camphoroquinone and Amine system) would be more desirable for minimizing microleakage after three-month storage.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.75-87
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• 2017

This study is the research about Okcheonjeong(玉泉亭) located in the backyard of Namhansanseong(南漢山城)'s temporary palace(行宮). Okcheonjeong was not only built by a government inside Namhansanseong but it was also representative garden which is shown the culture of the nobility. It became famous garden ruins recently because it has remained many carved stones. However, there has been no study about Okcheonjeong yet. We studied Okcheonjeong to establish basic knowledge by literature analysis and field investigation. We tried to discover garden style by deciphering carved stones, and estimate Okcheonjeong's location by documentary research. Sim, Sang-Gyu became Gwangjuyusu(廣州留守) in 1816, and he built Okcheonjeong on the backyard of Namhansanseong's temporary palace in 1817. It was located in the foot of a mountain beside a stream. It consisted of Pungaepok(楓靄瀑: waterfall), Chusudam(秋水潭: a little pond), and Okcheon(玉泉: a stone wall). The stone for sign stands in front of the entrance of Pungaepok to show Okcheonjeong, and there is Yeongyeondae(泠然臺) above the waterfall. We thought that Okcheonjeong was typical Imcheon-garden(林泉庭苑). Okcheonjeong is located in the foot of a mountain following Gamigyeong(歌薇逕) 60 meters so it was able to see the whole temporary palace from the Okcheonjeong. It was the garden pavilion of temporary palace, but it was used in semi public garden(半公的庭苑). Okcheonjeong is the only graden ruins which was located in Namhansanseong, so we have to preserve as cultural heritage. We expect to make use of primary datas to restore Namhansanseong soundly which was world heritage.

• Journal of Nutrition and Health
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• v.47 no.2
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• pp.89-98
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• 2014

Purpose: Association of low intake of calcium (Ca) and inadequate vitamin D (VD) status with higher prevalence rates of obesity has been reported. This study was conducted in order to investigate the effects of different levels of whey Ca and VD intake on lipid metabolism in growing rats. Methods: A total of 56 five-week-old male Sprague-Dawley rats were divided into seven groups and fed for five weeks. Ca groups were divided into three levels, low, normal, and high (0.25%, 0.5%, 1%). VD subgroups in the low and high Ca groups were divided into three levels, low, normal, and high (10 IU, 1,000 IU, and 5,000 IU). The effects of Ca and VD on each group were evaluated by two way ANOVA. Results: Significantly higher amounts of abdominal fat, visceral fat, and epididymal fat were observed in the Low-Ca groups than in the Normal-Ca and High-Ca groups. Serum leptin levels of Low-Ca groups were higher than those of Normal-Ca and High-Ca groups. The highest serum parathyroid hormone concentration was observed in the low Ca low VD group. The levels of serum 25(OH)D were significantly increased with increasing dietary VD levels. Significantly higher serum levels of triglycerides, total cholesterol, and HDL-cholesterol were observed in the low Ca groups than in the normal Ca and high Ca groups. Conclusion: These results indicate that low calcium intake increased serum lipid level and body fat amount.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.81-88
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• 1987

This study was conducted to determine the contents of heavy metals in Jeotkals (salted-fermented fish and shellfishes) and to investigate the major factor of their contamination. The results were as follows : Average contents of heavy metals in Jeotkals were Hg 0.076 ppm, Pb 0.677 ppm, Cd 0.112ppm, As 1.025ppm, Cu 3.540ppm, Zn 11.230ppm and Mn 2.041ppm, those in fish and shellfishes were Hg 0.051ppm, Pb 0.425ppm, Cd 0.071ppm, As 0.632ppm, Cu 2.ppm, Zn 8.052ppm, Mn 1.178ppm and Hg ND, Pb 0.05ppm, Cd 0.01ppm, As 0.02ppm, Cu 0.087ppm, Zn 0.068ppm and Mn 0.044ppm in salts. During the fermentation of the salted anchovy (Engraulis Japonicus) in each containers, the contents of Hg and Cd had little difference with control, but Pb was high in pottery and iron container and As was in iron and regenerated plastic container. During the fermentation of the salted anchovy in iron container, the contents of heavy metals increased and was to determined more at the later stage of fermentation than at the early stage. Most contents of heavy metals increased in elution experiment of containers, but Hg and Cd did not detected. The concentration of salt did not affect to the elution of heavy metals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.594-598
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• 1998

In this study oxidative deterioration of dried sea mussel and baby clam stored at $4{\pm}2^{\circ}C$ and $25{\pm}2^{\circ}C$ were investigated. Acid value of samples were higher at $25^{\circ}C$ than those at $4^{\circ}C$ throughout the storage period. And it was higher in dried baby clam than in sea mussel regardless of storage temperatures. Peroxide value of dried sea mussel and baby clam stored at $25^{\circ}C$ tended to decrease after 30 and 60 days, respectively. Thiobarbituric acid and carbonyl value of samples stored at $4^{\circ}C$ were higher than those stored at $25^{\circ}C$ throughout the storage period. In case of sea mussel, However they were lower stored at $4^{\circ}C$ than at $25^{\circ}C$ in 30 days. Amino nitrogen increased until 60 days and then decreased in all samples. Fluorescence intensity associated with interaction between carbonyl compound and amino compound was increased with storage temperature and time but it decreased slowly after 60 days.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.45-55
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• 1998

Phytoplankton community and primary productivity have been investigated in a fall season in the southern coastal waters of the last Sea, Korea. A strong thermocline formed at the 20\~60\;m$ layer and a cold water mass also existed in the bottom around Yong-il Bay. The offshore of the surveyed area was likely to be influenced by relatively warmer water, whereas the inshore represented Higher primary productivity with lower water temperature and lower salinity. A total of 133 species of phytoplankton occurred, representing 107 spp. of diatom, 23 spp. of dinoflagellate 3 spp. of silicoflagellate. Skeletonema costatum and Asterionellepsis glacialis were most predominant with more than $30\%$ dominance ratio, while Leptocylindrus danicus was also dominant at all transect lines. Standing crops of phytoplankton ranged from $2.7{\times}10^3\;to\;141.6{\times}10^3\;cell^{\ell-1}$. Chlorophyll a concentration varied with stations and layers, but the $30\~50$ m layer showed maximun with about $1.18{\mu}g{\ell}^{-1}$ rather than at the surface layer. It is believed that the maximun in standing crops and chlorophyll of phytoplankton formed at the $20\~50$ m layer above the thermocline during the survey. Phytoplankton primary productivity ranged from 0.32 to 3.04 mgC $m^{-3}\;hr^{-1}$, showing higher at the inshore than at the offshore. The range of integrated primary productivity was $263.3\~1085.5 mgC\;m^{-2}\;day^{-1}$ for the euphotic layer. Photosysthesis rates varied with the range from 0.76 to 8.04 mgC mgChl $\alpha^{-1}\;hr^{-1}$. Phytoplankton photosynthesis at the inshore was saturated at lower irradiance ($15\~35\%$ of surface) and showed higher efficiency, Thus, it revealed that the phytoplankton community probably adapted to the middle of euphotic layer because the depth of mixing layer became thinner due to the formation of thermocline.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.416-419
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• 1999

To evaluate lipid oxidation in dried shellfish during storage, brown pigment formation and composition of fatty acid were determined. Levels of brown pigment formation occurred at $25^{\circ}C$ were higher than those occurred at $4^{\circ}C$ throughout the storage period. Especially, the formation content of lipophilic brown pigment was 9$\~$10 times higher than that of hydrophilic brown pigment in all samples. Fatty acid composition of total lipid (TL) in fresh sea mussel and baby clam were $34.21\%$ and $32.83\%$ in saturated fatty acid, $19.50\%$ and $20,83\%$ in monoenoic acid, and $46.29\%$ and $46.79\%$ in polyenoic acid, respectively. The prominent fatty acids were 16:0, 16:1 and 20:5 in TL of the both samples. During storage, the contents of saturated fatty acid and monoenoic acid were slightly increased but that of polyenoic acid was decreased. In sea mussel, the content of polyenoic acid was higher in phospholipid (PL) than in neutral lipid (NL), while saturated fatty acid and monoenoic acid content were higher in the latter. The ratios of polyenoic acid/saturated fatty acid (P/S) in NL was similar in all samples. But the ratio of P/S in PL was higher in baby clam ($1.81\%$) than that in sea mussel($1.42\%$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.904-911
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• 2015

The objective of this study was to investigate the quality characteristics of traditional wine using an radio-frequency identification (RFID) system annexed to a fermenter. In this study, we proposed an RFID-based data transmission scheme for monitoring fermentation of traditional alcoholic beverages. The pH, total acidity, total sugar, soluble sugar, free sugar, alcohol content, and organic acids of were investigated and subjected to fermentation of traditional alcoholic beverages three times. The pH ranged from 7.98, 7.95, and 7.68 at day 0, decreased drastically to 3.31~2.96 at day 2, and then slowly increased to the end point, finally reaching 3.34 at day 20. Acidity tended to increase quickly with time, especially for all samples after day 2. The fermentation environment induced a sudden increase acidity in reactants and indicated a low pH. The total sugars during fermentation quickly decreased to the range of 20.3, 22.43, and 19.2% at day 2, and the slope of reduction steadily decreased to 5.1, 6.1, and 4.8% at day 10. On the other hand, the alcohol content showed the reverse trend as total sugars. The alcohol content also showed the same pattern as total acids, showing the highest alcohol content of 17.3% (v/v) on day 20. In this study on traditional wine fermentation using an RFID system, we showed that pH, soluble sugar, and alcohol content can be adopted as key indicators for quality control and standardization of traditional wine manufacturing.

• Journal of Korean Society of Forest Science
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• v.73 no.1
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• pp.63-69
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• 1986

In general, the snow injury in forestry is an unusual disaster. The degree of snow injury varies greatly depending on stand density and the local topography. This study was conducted to investigate the snow injury in analyzing the demaged by snow-fall in Jinju, Gyeongsangnamdo. The results obtained were summarized as follow; Among 466 total damaged trees, 425 trees were broken and 41 trees were uprooted, the ratio of damage were 5.22%, 2.49%, 0.92% and 0.2% for Pinus densiflora, Pinus thunbergii, Pinus rigida, Alnus hirsuta respectively. The 95% of the damage trees were in the range of 3 to 11 m for height and in the range of 3 to 20 cm for D. B. H.. The directions of the damage trees had a large influence by direction of the wind, but they shown at high tendency to aspect of the slope relatively. The 82% of the damaged trees ranged from 11 to 24 age. The ratio of broken height ($H_B/H$) indicated that the damage was most frequent in the part of stem as 24%, 45%, 31% in the part of the root collar (0.1), stem (0.2-0.4), crown (0.5-1.0) respectively. In general, trees with stem-form coefficient ($H_B/D$) over 0.7-0.8 are apt to suffer by snow damage. The average of stem-form coefficient of trees in this area was 1.06. Therefore, the ratio of damage was high tendency as 3.14%. These results indicate that it is necessary to apply pertinent tending which will increase in resistance of snow damage. As avalanches from the flank of soil erosion rise in an importance matter in present, it should also be considered to measures for prevention and restoration.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.1 s.6
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• pp.43-56
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• 2005

This research has examined a time series analysis(TSA) of an every hour traffic information such as occupancy, a traffic flow, and a speed, a statistical model of a surveyed data on the traffic fundamental diagram and an expand aspect of a traffic jam by many Parts of the traffic flow. Based on the detected data from traffic accidents on the Cheonan-Nonsan high way and events when the road volume decreases dramatically like traffic accidents it can be estimated from the change of occupancy right after accidents. When it comes to a traffic jam like events the changing gap of the occupancy and the mean speed is gentle, in addition to a quickness and an accuracy of a detection by the time series analyse of simple traffic index is weak. When it is a stable flow a relationship between the occupancy and a flow is a linear, which explain a very high reliability. In contrast, a platoon form presented by a wide deviation about an ideal speed of drivers is difficult to express by a statical model in a relationship between the speed and occupancy, In this case the speed drops shifty at 6$\~$8$\%$ occupancy. In case of an unstable flow, it is difficult to adopt a statistical model because the formation-clearance Process of a traffic jam is analyzed in each parts. Taken the formation-clearance process of a traffic jam by 2 parts division into consideration the flow having an accident is transferred to a stopped flow and the occupancy increases dramatically. When the flow recovers from a sloped flow to a free flow the occupancy which has increased dramatically decrease gradually and then traffic flow increases according as the result analyzed traffic flow by the multi regime as time series. When it is on the traffic jam the traffic flow transfers from an impeded free flow to a congested flow and then a jammed flow which is complicated more than on the accidents and the gap of traffic volume in each traffic conditions about a same occupancy is generated huge. This research presents a need of a multi-regime division when analyzing a traffic flow and for the future it needs a fixed quantity division and model about each traffic regimes.