• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.9-15
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• 2006

The quality of wood is largely depend on the characteristics of xylem tissue and their variation. They may include tracheid length, microfibril angle, distribution and amount of resin canal, as well as specific gravity as indicator of material properties. In this study, variation of these elements between and within 30 superior families of Pinus densifloa in progeny test forest were examined and the results are as follows; In terms of elongation ratio of tracheid length which is less than 1%, the sample tree showed a transition to matured wood after 13 years particularly in Kangwon 25, 30, 90, 56 and Chungnam 4 families. The average specific gravity were from 0.35 to 0.49, and differences between the families were significant. Number of transverse resin canal per unit area were also found to be significant between the families. The microfibril angles measured at 15th ring number ranged from 0.9 degree to 28.6 degree. More studies are necessary to tell whether these variation is inherited by genetic or individual characteristic. However it would be desirable that these elements be considered as key elements in the early stage of selection process of superior tree to ensure good quality of wood production in future.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.17-24
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• 2019

Carbon Fiber Reinforced Polymers(CFRP) has widely utilized as a material for rehabilitation because of its light-weight, deformability and workability. Because CFRP is brittle material whereas steel is ductile, it is inappropriate to apply conventional design approach for steel reinforcement. For ductile material, the behavior of combined elements is on average of that of unit element due to the stress redistribution between elements after yielding. Therefore, the mean value of the stress of combined elements is equal to that of unit element and the standard variation is smaller. Therefore, although the design value can increase, it is used as constant value because it is conservative and practical approach. However, for brittle material, the behavior of combined elements is governed by the weaker element because no stress redistribution is expected. Therefore, both the mean value and standard variation of the stress of combined elements decreases. For this reason, the design value would decrease as the number of element increases although it is eventually converged. In this paper, in brittle material, it is verified that the combination of unit element with normal distribution results in combined element with weibull distribution, so the modifying equation of mechanical properties is proposed with respect to the area load applied.

• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.31-37
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• 2010

It was investigated that morphological characteristics of leaf and stomata, chlorophyll contents and wood anatomy characteristics in Schisandra chinensis, Schisandra nigra and Kadsura japonica. Leaf morphological characteristics were significant at 5% levels within the species and within the individuals as a male, a female and monoecious. K. japonica was the longest in the leaf length, followed by S. chinensis and S. nigra. For the leaf length among S. nigra individuals, the female was longer than male and monoecious. As for the Petiole length, S. nigra was twice longer than S. chinensis and K. japonica. Stomata length was ranged from $92.5\;{\mu}m$ to $105.9\;{\mu}m$ for S. nigra, $79.9\;{\mu}m$ for S. chinensis, $76.2\;{\mu}m$ for K. japonica. S. nigra was longer than the others in length and width, while its stomata density was lower than the others. The size of vessel elements and xylem fiber showed a similar tendency to stomata, significant at 5% levels within S. nigra individuals (male, female and monoecious). Chlorophyll contents were also variable in inter and intra species and in general K. japonica showed higher levels of chlorophyll contents than Schisandra spp. plants.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.71-71
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• 2019

고사리(Ferns)는 고사리 속(Pteridium spp.)에 속하는 양치식물의 총칭으로서 우리나라에는 22과 70속 272종이 분포되어 있는 것으로 보고되었다. 고사리의 어린 순에는 가식부 100 g 당 칼슘 15.0mg, 칼륨 185.0mg 등이 함유되어 있으며 골다공증, 심혈관질환 등에 효과가 있고 식이섬유로 인해 변비 예방에도 유용한 것으로 알려져 있다. 고사리 뿌리에서 추출한 전분은 중국 및 일본 등지에서 면류나 제과용으로 이용되고 있어 고사리 재배의 부가가치를 향상시킬 수 있는 방안으로 기대되고 있다. 본 연구에서는 고사리 뿌리는 가정용믹서기로 분쇄하는 방법과 고무망치를 사용해 파쇄한 방법에서 식품첨가제로 이용되고 있는 sodium metabisulfite 등 3종의 산화방지제를 사용하여 추출한 전분의 이화학적 특성을 조사하였다. 고사리 전분의 추출 수율은 분쇄하는 방법에서 높은 경향이었고 추출용액 중에서는 sodium metabisulfite 4% 용액에서 분쇄 처리 9.5%와 파쇄 처리 8.3%로 가장 높은 수율을 보였고, ascorbic acid 침지에서는 5.1%와 5.5%로 낮은 수율을 나타냈다. 추출한 전분의 색도값에서는 파쇄하는 처리에서 L 값이 높아지고 a와 b 값은 낮아지는 경향이었고 sodium metabisulfite 4% 용액 침지에서 분쇄와 파쇄 두 방법에서 가장 높은 명도값을 보였다. 고사리 전분의 추출방법별 Ca 함량은 분쇄 처리에 파쇄 처리에서 높아지는 양상을 보였고 파쇄 후 ascorbic acid 4% 용액에서 추출하는 처리에서 0.23%로 가장 높았으며, Mg 함량도 분쇄 처리에 비해 파쇄 처리에서 경미하게 높은 양상을 보였다. 유효태 Fe 함량 또한 파쇄처리에서 높은 경향을 보였고 추출 용액중에서는 ascorbic acid 4% 용액이 0.12%의 높은 함량을 보였다. 고사리 전분의 추출방법별 호화특성에서 최고 점도는 증류수, ascorbic acid 및 sodium carbonate 추출에서는 파쇄하는 방법에서 높아지는 경향이었지만 sodium metabisulfite 추출에서는 감소하는 경향을 보였다. 강하점도는 모든 추출용액에서 분쇄 처리에 비해 파쇄 처리에서 현저하게 증가하는 양상을 보였고 치반점도는 sodium metabisulfite와 ascorbic acid 추출은 파쇄처리에서 83.9 RVU와 53.0RVU로 낮아지는 경향을 보인 반면 sodium carbonate와 증류수 추출에서는 증가하는 양상을 나타냈다. 호화시간은 분쇄 처리가 파쇄 처리에 비해 약간 늘어나는 경향이었고 추출용액 간에는 큰 차이가 없었으며 호화온도는 분쇄처리가 파쇄 처리에 비해 높아지는 결과를 나타냈으며 파쇄한 고사리 뿌리를 증류수를 이용해 추출한 전분에서 가장 낮은 $69.7^{\circ}C$의 호화온도를 보였다.

• Economic and Environmental Geology
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• v.51 no.4
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• pp.309-322
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• 2018

Naturally occurring asbestos (NOA) occurs in rocks and soils as a result of natural weathering and human activities. It is proved that inhalation of asbestos fibers can lead to increase risk of developing several diseases such as lung cancer and malignant mesothelioma. The parent rocks of asbestos have been mainly associated with (ultra)mafic and carbonate rock. The previous studies on NOA were mainly limited to (ultra)mafic rock-hosted asbestos, but studies on carbonate rock-hosted asbestos are relatively rare in S. Korea. Therefore, this study was aimed to examine mineralogical characteristics of carbonate rock-hosted NOA at three sites including Muju and Jangsu, Jeonbuk province and Asan, Chungnam province. Types of rocks at the three sites mainly consisted of Precambrian metasedimentary rocks, carbonate rock, and Cretaceous and Jurassic granites. Asbestos-containing carbonate rock samples were obtained for mineralogical characterization. XRD, PLM, EPMA, SEM and EDS analyses were used to characterize mineralogical characteristics of the carbonate rock-hosted NOA. From the carbonate rock, fibrous minerals were occurred acicular and columnar forms in the three sites. Fibrous minerals were composed of mainly tremolite and associated minerals included possibly asbestos containing materials (ACM) such as talc, vermiculite, and sepiolite. The length and aspect ratios of tremolite were similar to the standard asbestiform (length >$5{\mu}m$, length:width = 3:1). These results indicate that both non-asbestiform and asbestiform tremolite with acicular forms occurred in carbonate rocks at three sites. Geological and geochemical characteristics and mineral assemblages indicate tremolite and associated minerals might be formed by hydrothermal alternation and/or hydrothermal veins of carbonate rocks due to intrusion of acidic igneous rocks.

• Journal of Nutrition and Health
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• v.50 no.6
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• pp.565-577
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• 2017

Purpose: There have been limited studies investigating the relationship between high-sensitivity C-reactive protein (hsCRP), metabolic diseases, and dietary factors in Korean adults. Here, we examined the association between nutrient intake and serum hsCRP among Korean adults. Methods: Using data on 2,624 healthy Korean adults (1,537 women and 1,087 men) from the 2015 Korea National Health and Nutrition Examination Survey, demographic, anthropometric, biochemical, and dietary factors were analyzed once the subjects were grouped into either sex, age, or BMI. Nutrient intake was evaluated using the dietary data obtained by one-day 24-hour recall. Based on the guidelines of the US Centers for Disease Control and Prevention and the American Heart Association, hsCRP level was classified as HCRPG (High CRP Group, hsCRP > 1 mg/L) and LCRPG (Low CRP Group, hsCRP ${\leq}1mg/L$). Proc surveyreg procedure was performed to examine the associations between nutrient intake and hsCRP after adjustment for potential confounding variables. Results: The average hsCRP level of healthy Korean adults was $0.95{\pm}0.03mg/L$ ($0.97{\pm}0.04mg/L$ in men, $0.92{\pm}0.05mg/L$ in women). Obese subjects had significantly higher hsCRP than non-obese subjects in both sexes. The hsCRP level was positively associated with current smoking, physical inactivity, BMI, waist circumference, fasting blood glucose, triglycerides, total cholesterol, LDL-cholesterol, and blood pressure and inversely associated with HDL-cholesterol. LCRPG had significantly higher intake of dietary fiber compared to HCRPG in women. High hsCRP level was associated with more dietary cholesterol intake but less omega-3 fatty acid intake among subjects aged ${\geq}50y$. HCRPG of obese subjects had higher intakes of fat and saturated fatty acid than LCRPG. Conclusion: The hsCRP level is closely associated with several lifestyle variables and nutrient intake in healthy Korean adults. Individuals with high hsCRP level show low intakes of dietary fiber and omega-3 fatty acids but high intakes of dietary fat and cholesterol. Our findings suggest that a potential anti-inflammatory role for nutrients and lifestyle in the Korean adult population.

• Food Science and Preservation
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• v.17 no.5
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• pp.652-658
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• 2010

This study was to investigate physicochemical properties of Shinan seomcho growing in Jeollanamdo. The samples used were Shinan seomcho(Josaeng, Mansaeng varieties), Pohangcho(Josaeng, Mansaeng varieties), Namhaecho (Josaeng, Mansaeng varieties) and greenhouse spinach(Josaeng varieties). The results were as follows ; The thickness of spinach leaves were contained in order of Shinan seomcho > Pohangcho > Namhaecho > greenhouse spinach, and the hardness of those were contained in order of Pohangcho > Namhaecho > Shinan seomcho > greenhouse spinach. In Hunter's color value, L, a, b value in greenhouse spinach was lower than those of the others. Among the spinach varieties, Josaeng-jong(3.39~5.38 mg%) had the highest level of total dietary fiber contents than that of Mansaeng-jong(2.94~3.91 mg%). By regional groups, total dietary fiber were contained in order of Pohangcho > Namhaecho > Shinan seomcho > greenhouse spinach. The free sugar contents in the sample group, Shinan seomcho(4 varieties), Pohangcho(1 variety) and Namhaecho(2 varieties) were higher than those of other spinach varieties. The total sugar contents in the sample group, Shinan seomcho(3 varieties), Pohangcho(1 variety) and Namhaecho(2 varieties) were higher than those of other spinach varieties. Total flavonoid contents of Shinan seomcho(Josaeng-jong) and Namhaecho(Josaeng-jong) were lower than 130 mg%, but the other spinach had more than 130 mg% of total flavonoid contents. Germanium contents were detected in the following order ; Shinan seomcho(47.46 ${\mu}g$/kg) > Namhaecho(30.13 ${\mu}g$/kg) > Pohangcho(26.39 ${\mu}g$/kg) > greenhouse spinach(25.32 ${\mu}g$/kg).

• The Journal of Engineering Geology
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• v.33 no.4
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• pp.543-553
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• 2023

The current status of domestic a agalmatolite mines in South Korea was investigated with a view to establishing a stable supply of agalmatolite and managing its demand. Most mined agalmatolite deposits were formed through hydrothermal alteration of Mesozoic volcanic rocks. The physical characteristics of pyrophyllite, the main constituent mineral of agalmatolite, are as follows: specific gravity 2.65~2.90, hardness 1~2, density 1.60~1.80 g/cm³, refractoriness ≥29, and color white, gray, grayish white, grayish green, yellow, or yellowish green. Among the chemical components of domestic agalmatolite, SiO₂ and Al₂O₃ contents are respectively 58.2~67.2 and 23.1~28.8 wt.% for pyrophyllite, 49.2~72.6 and 16.5~31.0 wt.% for pyrophyllite + dickite, 45.1 and 23.3 wt.% for pyrophyllite + illite, 43.1~82.3 and 11.4~35.8 wt.% for illite, and 37.6~69.0 and 19.6~35.3 wt.% for dickite. Domestic agalmatolite mines are concentrated mainly in the southwest and southeast of the Korean Peninsula, with some occurring in the northeast. Twenty-one mines currently produce agalmatolite in South Korea, with reserves in the order of Jeonnam (45.6%) > Chungbuk (30.8%) > Gyeongnam (13.0%) > Gangwon (4.8%), and Gyeongbuk (4.8%). The top 10 agalmatolite-producing mines are in the order of the Central Resources Mine (37.9%) > Wando Mine (25.6%) > Naju Ceramic Mine (13.4%) > Cheongseok-Sajiwon Mine (5.4%) > Gyeongju Mine (5.0%) > Baekam Mine (5.0%) > Minkyung-Nohwado Mine (3.3%) > Bugok Mine (2.3%) > Jinhae Pylphin Mine (2.2%) > Bohae Mine. Agalmatolite has low thermal conductivity, thermal expansion, thermal deformation, and expansion coefficients, low bulk density, high heat and corrosion resistance, and high sterilization and insecticidal efficiency. Accordingly, it is used in fields such as refractory, ceramic, cement additive, sterilization, and insecticide manufacturing and in filling materials. Its scope of use is expanding to high-tech industries, such as water treatment ceramic membranes, diesel exhaust gas-reduction ceramic filters, glass fibers, and LCD panels.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.46-52
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• 1997

Diaphragm is thought to play the most important role in breathing and has a substantially greater proportion of slow oxidative and fast glycolytic fibers, and low proportion of fast oxidative fibers. The respiratory muscle, diaphragm, has the functional characteristics of slow speed of contraction, high resistance to fatigue and the ability to respond to intermittent ventilatory loads, for example of exercise. In the present study, the characteristics of the metabolism (depletion and repletion) of glycogen and the structural changes of diaphragm during depletion and repletion of glycogen were observed in rats. For comparison, the red gastrocnemius muscle which has a greater proportion of fast oxidative glycolytic (FOG) and slow oxidative (SO) fibers, and low proportion of fast glycolytic (FG) fiber, was also studied. The glycogen concentration of diaphragm in overnight fasted rats was $2.30{\pm}0.14mg/gm$ wet weight. The values of glycogen concentration at 60, 90 and 120minutes of treadmill exercise loaded rats was significantly decreased compared to that of the overnight fasted rats. There was no significant difference among the glycogen concentrations of diaphragm at 60, 90 and 120minutes of exercises. The glycogen concentration of diaphragm was decreased to $1.12{\pm}0.17$ from $2.30{\pm}0.14mg/gm$ wet weight by treadmill exercise. The glycogen depletion rate of diaphragm during exercise was faster than that of red gastrocnemius in both of the first 60minutes and 120minutes duration of exercise. The glycogen repletion of diaphragm after intragastric glucose administration by stomach tube was studied in control and exercise groups. The glycogen concentration was significantly increased after glucose administration in both of control and exercise groups. All of the concentration of exercise group at 60, 120 and 180minutes after glucose administration was significantly higher than those of control group. In conclusion, one of the characteries of diaphragm in glycogen metabolism is fast glycogen depletion during exercise, and slowness of glycogen repletion after glucose ingestion in rats.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1334-1342
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• 2015

The aim of this study was to investigate the quality characterization of salmon oil microencapsulated with maltodextrin (MD), cyclodextrin (CD), sodium caseinate (SC), arabic gum (AG) and WPI. After spray drying to ambient temperature, the salmon oil powders were packed (single package) and placed at room temperature ($25^{\circ}C$) for 30 day. The quality characterization of salmon oil powder including total oil (%), extractable oil (%), encapsulation efficiency (%), fatty acid, SEM, pH, acid value (AV), peroxide value(POV) were investigated. Salmon oil was microencapsulated with a high power yield (> 80%); including the formulation MD/SC and MD/SC/WPI. The microencapsules of MD/SC/WPI presented spherical shapes, smooth texture and non-porous surfaces. The pH of MD/SC/WPI varied from 6.11 to 5.99 (p>0.05). The AV of MD/SC/WPI varied from 4.74 to 4.61 (p>0.05). The pH and AV were not significantly different. The POV of MD/SC/WPI increased with storage day (p<0.05). It was concluded that MD/SC/WPI could delay lipid oxidation and high yield (82.55%) of salmon oil powder.