• Journal of the Korean Vacuum Society
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• v.18 no.4
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• pp.318-330
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• 2009

A high heat flux test facility using a graphite heating panel was constructed and is presently in operation at Korea Atomic Energy Research Institute, which is called KoHLT-1. Its major purpose is to carry out a thermal cycle test to verify the integrity of a HIP (hot isostatic pressing) bonded Be mockups which were fabricated for developing HIP joining technology to bond different metals, i.e., Be-to-CuCrZr and CuCrZr-to-SS316L, for the ITER (International Thermonuclear Experimental Reactor) first wall. The KoHLT-1 consists of a graphite heating panel, a box-type test chamber with water-cooling jackets, an electrical DC power supply, a water-cooling system, an evacuation system, an He gas system, and some diagnostics, which are equipped in an authorized laboratory with a special ventilation system for the Be treatment. The graphite heater is placed between two mockups, and the gap distance between the heater and the mockup is adjusted to $2{\sim}3\;mm$. We designed and fabricated several graphite heating panels to have various heating areas depending on the tested mockups, and to have the electrical resistances of $0.2{\sim}0.5$ ohms during high temperature operation. The heater is connected to an electrical DC power supply of 100 V/400 A. The heat flux is easily controlled by the pre-programmed control system which consists of a personal computer and a multi function module. The heat fluxes on the two mockups are deduced from the flow rate and the coolant inlet/out temperatures by a calorimetric method. We have carried out the thermal cycle tests of various Be mockups, and the reliability of the KoHLT-1 for long time operation at a high heat flux was verified, and its broad applicability is promising.

• Journal of the Korean Wood Science and Technology
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• v.33 no.1 s.129
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• pp.87-96
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• 2005

This study was carried out to evaluate the shear bond strength and adhesive bond durability of structural glued laminated timber (glulam) manufactured with mixed species lumber of Korean red pine, Korean pine and Japanese larch, using resorcinol adhesive and water-based polymeric-isocyanate adhesive (WPI). Each board used as a glulam lamina was graded by visual inspection. The visual lumber grade of the all species was very low due to the large size and number of knots and the steep slope of grain. In view of the results, appropriate pruning, sawing and drying processes might be needed to produce high grade lamina lumber with small knot size and drying defect free. Shear bond strength of every tested glulam specimen ranged between 7.9 and $9.9N/mm^2$, and much higher than the Korean Standard (KS) for glulam shear bond strength, $7.1N/mm^2$. There was not much shear bond strength difference between wood/resorcinol and wood/WPI. The resorcinol adhesive bond durability exceeded KS requirements. However, delamination on the end-grain surfaces of WPI glulam submerged in both room temperature and boiling water severely occurred, and its durability did not meet KS requirements. Further investigations may be required, and special care should be taken, to ensure long service life of WPI glulam used for exterior application. Results of this study are expected to be useful for improvement of mechanical properties and structural performance of mixed species glulam.

• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.743-760
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• 2014

This study aimed to isolate and identify freshwater algae from the organic agricultural ecosystems and investigate its biological characteristics to study the possibility of utilizing a biomass freshwater algae in organic farming. In the survey area, average water temperature was $12.4{\sim}28.2^{\circ}C$ and the pH ranges were from 6.1 to 8.5. The solid culture method is more suitable than liquid culture method for isolation of freshwater algae with lower contamination level and higher isolation frequency. A total of 115 strains were isolated from six freshwater algae habitats in nine regions in Korea. BGMM (BG11 Modified Medium) amended with NaNO3 and $KNO_3$ as a nitrogen, and $Na_2CO_3$ as carbon source was designed to isolate and culture freshwater algae. Absorbance of freshwater algae culture has increased dramatically to four days and decreased after eight days after inoculation. CHK008 of the seven isolates showed the highest absorbance in seven days after culturing in BGMM. The optimal pH of BGMM for culturing freshwater algae was pH 6-7. As light intensity increased, growth of freshwater algae increased. Among the five kinds of carbon sources, glucose and galactose promoted good growth of freshwater algae in BGMM. The colony color of purified 16 green algae isolates showed a separation of green, dark and light green, and of them, eleven algae strains showed a strong fluorescent light under fluorescence microscopy. Cell size of the green algae showed a wide range of variation depending on the species. General morphology of the green algae strains was spherical. Chlamydomonas sp. was elliptical, and Chlorella sorokiniana was ellipsoidal and cylindrical. All strains of the green algae except for Chlamydomonas sp. did not have flagella. One isolate of Chlamydomonas sp. and five isolates of C. sorokiniana secreted mucus. Sixteen isolates of 16 green algae were identified as two family and six species, Chlorella vulgalis, C. sorokiniana, C. pyrenoidosa, C. kessleri, C. emersonii, and Chlamydomonas sp. based on their morphological characteristics.

• Korean Journal of Ecology and Environment
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• v.36 no.2 s.103
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• pp.124-138
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• 2003

This paper aimed to analyze the relationship between alga3 bloom patterns and hydrological, limnological data which were collected from major reservoirs in Korea for 8 years (1990${\sim}$1997). Water temperature of river-type reservoirs showed wider seasonal fluctuations than that of lake-type. pH of lake-type reservoirs was low in winter season but high in summer season. In contrast, river-type reservoirs showed high pH in spring and autumn seasons as well, and very low in summer season. COD of lake-type reservoirs and Paldang reservoir was lower (2${\sim}$3 mg/L) than that of Geumgang and Nagdonggang reservoirs (6${\sim}$9 mg/L). Dissolved oxygen (DO) of river-type reservoirs was higher than that of lake-type reservoirs. Seasonal fluctuation pattern of DO saturation in river-type reservoirs was high (80 ${\sim}$100%) and remained relatively constant whereas lake-type reservoirs showed the highest level (93%) in late spring or early summer, which gradually decreased entering winter season(46${\sim}$06%). And monthly variation of DO saturation showed inverse proportion to water volume in lake-type reservoirs. Nutrients concentration in river-type lake is higher than lake-type. Seasonal fluctuation of nutrients (T-N, T-P) in lake-type reservoirs was relatively small than that of river-type reservoirs. Annual mean N/P mass ratio of lake-type reservoirs was higher than that of river-type. Transparency tended to related with the suspended solid concentration in river-type reservoirs. Algal bloom of lake-type and river-type reservoirs occurred at any time except rainfall and winter periods. And it dominated in summer and early autumn, respectively. Algal bloom of river-type reservoirs was higher than that of lake-type. Relationship between rainfall and chlorophyll- a in lake-type reservoirs was relatively high, however river-type reservoirs showed insignificant.

• Korean journal of food and cookery science
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• v.28 no.4
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• pp.375-382
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• 2012

The quality characteristics of granules prepared from water and 50% ethanol extracts of mulberry and blueberry were investigated. The total polyphenol and total flavonoid contents of mulberry and blueberry were higher in the 50% ethanol extract than those in the water extract. Total anthocyanin content was highest in the 50% mulberry ethanol extract (470.91 mg/100 g). Oxygen radical absorbance capacity (ORAC) of the mulberry and blueberry extracts was 335.37 ${\mu}moles\;TE/g$ and 238.14 ${\mu}moles\;TE/g$, respectively. Superoxide radical scavenging activity of the mulberry and blueberry extracts increased with an increase in extract concentration. Total polyphenol and flavonoid contents of granules from the mulberry extract were 4.83 mg/mL and 3.49 mg/mL, respectively. Total anthocyanin content of granules from the mulberry and blueberry extracts was 76.26 mg/100 g and 75.26 mg/100 g, respectively. Electron donating ability and ORAC of granules from the mulberry and blueberry extracts were 45.09% and 24.10%, 87.65 ${\mu}moles\;TE/g$ and 57.59 ${\mu}moles\;TE/g$, respectively. Granules that were stored for 7 weeks at room temperature had low anthocyanin content degradation and Hunter color values (L, a, and b).

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.402-409
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• 2000

To investigate the textural and physical characteristics of WSF(whole soybean flour) tofu affected by coagulant and its concentration, $CaCl_2$, $CaSO_4$, $GDL(glucono-{\delta}\;lactone)$, $MgCl_2$, and some mixed coagulants were used in this study. Yields of WSF tofu coagulated with $CaSO_4$ and GDL were ranged 4.3-4.5(g/g WSF), but common tofu was 2.2-3.0(g/g soybean). As the water addition ratio increased, L and a value were increased while heating time increased, b value increased. L value of WSF tofu was lower and b value was higher than conventional tofu and 4 commercial tofus. Kinds of coagulant and its concentration significantly affected to textural properties of WSF tofu. As the concentration of coagulant increase, the hardness increased in most all coagulants. WSF tofu coagulated with $CaSO_4$ and GDL recorded low hardness and adhesiveness, and high springiness among the used coagulants at the same concentration. As the hardness increased, the gumminess and chewiness increased in most all coagulants. As coagulation temperature and molding pressure increase, hardness also increased. WSF tofu coagulated with 0.3% $CaSO_4+GDL$ was the most similar in the textural properties with conventional tofu and 4 commercial tofus. WSF tofu coagulated with 0.3% of $CaSO_4+GDL$ at $85^{\circ}C$, 10 times water addition, 5min. heating and $25.0g/cm^2$ molding pressure recorded the highest score in the sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.320-330
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• 1978

Riced dehydrated potato granules with a good reconstituton quality was made from Irish Cobber (IC) and Shimabara which are representative varieties in Korea. A part of IC potato granules was packed in small vinyl-bags while the rest, including some BHA (75ppm)-treated granules, was packed in $301{\times}407$ plain tin cans. These granules were stored in a room at room temperature, and their physico-chemical properties and lipid composition were studied. The color of the granules was measured with a Hunter-type Tristimules colorimeter. L, $a_L,$ and $b_L-values$ were respectively 83.8, -1.1 and 18.3. Variety and package-type did not affect the color. In general, it was darker than that of commercial wheat flour, but whiter than that of commercial defatted soy flour. At $100^{\circ}C$, the granules, irrespective of variety and package-type, absorbed water rapidly, and reached the maximum moisture content of $90{\sim}92%$ in 3 min., whereas they absorbed water more slowly at $8{\sim}14^{\circ}C$, and reached the maximum content of $72{\sim}74%$ in 5 minutes. Peroxide, TBA, carbonyl, acid, and iodine values of the granules after 3 months storage were respetively $150{\sim}460\;meq/kg,\;20{\sim}26,\;154{\sim}380$ micromole, $24{\sim}59,\;and\;70{\sim}78$. Except iodine values, all the chemical values were affected by variety and package-type. Ether and $CHCl_3-extracts$ of the granules from IC and Shimabara were subjected to GLC and TLC analyses. In case of IC, the major fatty acids were palmitic, stearic, and oleic (30.0, 18.8, 40.6), while in case of Shimabara they were palmitic, oleic, and linoleic acids (26.7, 39.6, 23.4%). The major lipid classes were, in both cases, triglycerides and phospholipids. Their contents were raspectively 19.1 and 43.1 (IC), and 30.1 and 37.4% (Shimabara).

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.251-262
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• 2010

In order to provide quantitative control of the standard products of Geostationary Ocean Color Imager (GOCI), on-board radiometric correction, atmospheric correction, and bio-optical algorithm are obtained continuously by comprehensive and consistent calibration and validation procedures. The calibration/validation for radiometric, atmospheric, and bio-optical data of GOCI uses temperature, salinity, ocean optics, fluorescence, and turbidity data sets from buoy and platform systems, and periodic oceanic environmental data. For calibration and validation of GOCI, we compared radiometric data between in-situ measurement and HyperSAS data installed in the Ieodo ocean research station, and between HyperSAS and SeaWiFS radiance. HyperSAS data were slightly different in in-situ radiance and irradiance, but they did not have spectral shift in absorption bands. Although all radiance bands measured between HyperSAS and SeaWiFS had an average 25% error, the 11% absolute error was relatively lower when atmospheric correction bands were omitted. This error is related to the SeaWiFS standard atmospheric correction process. We have to consider and improve this error rate for calibration and validation of GOCI. A reference target site around Dokdo Island was used for studying calibration and validation of GOCI. In-situ ocean- and bio-optical data were collected during August and October, 2009. Reflectance spectra around Dokdo Island showed optical characteristic of Case-1 Water. Absorption spectra of chlorophyll, suspended matter, and dissolved organic matter also showed their spectral characteristics. MODIS Aqua-derived chlorophyll-a concentration was well correlated with in-situ fluorometer value, which installed in Dokdo buoy. As we strive to solv the problems of radiometric, atmospheric, and bio-optical correction, it is important to be able to progress and improve the future quality of calibration and validation of GOCI.

• Food Engineering Progress
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• v.14 no.4
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• pp.299-306
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• 2010

This study was performed to develop new functional red ginseng drinks with Astragali Radix and Opuntia humifusa. Optimum extraction conditions such as solvent property and temperature for Astragali Radix were determined by distilled water vs. ethanol (95%) ratio (0:100, 25:75, 50:50, 75:25) and 60 vs. $80^{\circ}C$. Water-soluble extracts at $80^{\circ}C$ showed higher antioxidant activities than fat-soluble extracts at $60^{\circ}C$. Viscosities of 1-2% (w/v) of Opuntia humifusa solution were similar to that of the 0.1% guar gum solution. Addtion of Astragali Radix (3% and 5%, w/v) and Opuntia humifusa (1.2%, w/v), especially, had effect on the changes of pH of the red ginseng solution(5%, w/v) during storage for 7 days. A significant difference during the storage was shown in total plate counts by addition of Opuntia humifusa (1.2%, w/v) and microorganisms were reduced by six log cycles. Significant antiproliferation effects of red ginseng (5%, w/v) solution with Astragali Radix (3% & 5%, w/v) and Opuntia humifusa (1.2%, w/v) on Colon26m-3.1 carcinoma (colorectal carcinoma) cell and U87-MG neuronale glioblastoma (brain carcinoma) cell were not observed.

• Journal of Nutrition and Health
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• v.52 no.3
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• pp.250-257
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• 2019

Purpose: Aster glehnii (AG) and Aster yomena (AY) are medicinal plants that belong to the family Compositea and grow widely in Korea. Plants in the genus Aster have been used to treat snakebite wounds or bruises in oriental medicine. This study compared the effects of anti-oxidants and anti-adipocyte differentiation according to the species (the aerial parts of AG and AY). Methods: AG and AY were extracted using 70% ethanol (-E) and water (-W) at room temperature. The anti-oxidant activities were measured by total phenol contents (TPC), total flavonoid contents (TFC), DPPH and $ABTS^+$ assay. In addition, correlation analysis was performed for the anti-oxidant compounds and effect. The level of anti-adipocyte differentiation was assessed using an oil red O assay on pre-adipocytes. Results: AG-W showed higher TPC ($6.92{\mu}g/mL$) and AG-E presented higher TFC ($8.22{\mu}g/mL$) than the other extracts. Furthermore, AG-E exhibited higher radical scavenging activity in the DPPH and $ABTS^+$ assay ($IC_{50}$: 104.88 and $30.06{\mu}g/mL$). In the cytotoxicity assay, AG and AY extracts at concentrations less than $100{\mu}g/mL$ were non toxic. AG-W reduced the lipid accumulation of 3T3-L1 cells significantly after differentiation (70.49%) compared to the other extracts. Conclusion: These results show that the water extract of AG has anti-oxidant effects and reduces the differentiation of 3T3-L1 cells. Therefore, AG has utility as a functional food material for its anti-oxidant activities and ability to prevent lipid accumulation.