• Korean Journal of Materials Research
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• v.8 no.7
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• pp.584-590
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• 1998

The microstructures of finely distributed Si-phases in $\beta$-$FeSi_2$ thermoelectric matrix, were produced by heat-treating the melt-cast ingots of single $\alpha$-$Fe_2Si_5$ phase at 730~85$0^{\circ}C$ for 4~20 hours, or by resistance-hot-pressing the mechanically alloyed powders ordinarily consisting of $\varepsilon$-FeSi and Si phases at 760~85$0^{\circ}C$ for 10 minutes of composition. $(Fe_{0.98}Mn_{0.02})_xSi_2(x{\leq$}1) The size and interspacing of dispersed Si-phases were able to control within a range of 0.05~0.27$\mu\textrm{m}$ and 0.2~0.6$\mu\textrm{m}$ by variations of heat treatment temperature and sintering temperature as well as the composition. respectively. The dispersion of Si- phases was expected to be effective for the reduction of thermal conductivity responsible for the increment of thermoelectric figure of merit.

• Korean Journal of Ichthyology
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• v.17 no.3
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• pp.205-216
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• 2005

Variation of anchovy spawning grounds was analyzed based on egg distribution and oceanographic factors in southern coastal waters of Korea in April, June, and August of 2003 and 2004. Environmental factors showed a range of $10.2{\sim}30.7^{\circ}C$ in surface temperature, 25.7~34.7 in surface salinity, $0.14{\sim}0.67{\mu}g/L$ in chlorophyll-a, and $111.52{\sim}262.37mg/m^2$ in zooplankton biomass. Eggs were mainly distributed in temperatures of $14.7{\sim}26.9^{\circ}C$ and salinities of 31.0~34.6 in accordance with seasonal variation of temperature and salinity. Egg density increased in accordance with the high level of zooplankton biomass during the summer season. Anchovy spawning grounds during August of 2004 tended to concentrate in the outward front area between offshore warm-water and coastal cool-water masses.

• Korean Journal of Plant Resources
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• v.27 no.3
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• pp.263-270
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• 2014

Loranthus tanakae (Franch. & Sav.) is an endangered species of mistletoe, distributed in Korean peninsula. The objective of our research is to determine the effect of storage duration and conditions [air flow (AF) and air tight (AT)] at different temperatures for survivability and germination of mistletoe seeds, and also to monitor the effect of seed scarification on germination in vitro. The result revealed that the seeds stored in natural conditions (no stratification) showed highest survival rate of 100% and retained up to 93.3% even after two months of storage in natural conditions and showed higher germination percentage (90%) compare to after ripened seeds. However, the seed stored at $0^{\circ}C$ decreased the germination percentage (ranged from 63 to 73%). Therefore, it can be confirmed that mistletoe does not need after ripened treatment to promote germination. Our research also showed that the storage of L. tanaka seeds in freezing temperatures of $-20^{\circ}C$ and in room temperature for long time either in AT or AF conditions caused the loss of survival and germination rate. On the other hand, the chemical scarification (0.01N HCl incubation for 12 hrs. at $38^{\circ}C$) method was proven more effective to enhance germination percentage of L. tanakae. Regarding the temperature regime, $22^{\circ}C$ showed early germination of mistletoe seeds in vitro.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.12
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• pp.1359-1364
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• 2012

The C-band semi-lumped lowpass filter with broad stopband and compact size characteristic using chip inductor is proposed. To provide an additional attenuation pole in stopband by SRF, a separable inductor is added to proposed structure, and it has broad stopband characteristic. The third order elliptic function lowpass filter with chip inductor(L: 9.1 nH, SRF: 5.5 GHz, Q: 25) has insertion loss of 0.38 dB, cutoff frequency of 920 MHz, broad stopband(below 20 dB) of 1.43~7.8 GHz and the size is reduced 37.4 % compared to distributed inductor.

• Korean Journal of Remote Sensing
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• v.35 no.2
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• pp.251-263
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• 2019

Sentinel-2 Multi Spectral Instrument(MSI) launched by the European Space Agency (ESA) offered high spatial resolution optical products, enhanced temporal revisit of five days, and 13 spectral bands in the visible, near infrared and shortwave infrared wavelengths similar to Landsat mission. Landsat satellite imagery has been applied to various previous studies, but Sentinel-2 optical satellite imagery has not been widely used. Currently, for global coverage, Sentinel-2 products are systematically processed and distributed to Level-1C (L1C) products which contain the Top-of-Atmosphere (TOA) reflectance. Furthermore, ESA plans a systematic global production of Level-2A(L2A) product including the atmospheric corrected Bottom-of-Atmosphere (BOA) reflectance considered the aerosol optical thickness and the water vapor content. Therefore, the Sentinel-2 L2A products are expected to enhance the reliability of image quality for overall coverage in the Sentinel-2 mission with enhanced spatial,spectral, and temporal resolution. The purpose of this work is a quantitative comparison Sentinel-2 L2A products and fully simulated image to evaluate the applicability of the Sentinel-2 dataset in cultivated land growing various kinds of crops in Korea. Reference image of Sentinel-2 L2A data was simulated by airborne hyperspectral data acquired from AISA Fenix sensor. The simulation imagery was compared with the reflectance of L1C TOA and that of L2A BOA data. The result of quantitative comparison shows that, for the atmospherically corrected L2A reflectance, the decrease in RMSE and the increase in correlation coefficient were found at the visible band and vegetation indices to be significant.

• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.229-247
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• 2014

Seven feeding trials were conducted to determine the effects of feeding rate and frequency in the Korean rockfish Sebastes schlegeli at seven different water temperatures. Two feeding-rate experiments for 5-g Korean rockfish at $17^{\circ}C$ and $20^{\circ}C$; three feeding rate experiments for 16-g Korean rockfish at $16^{\circ}C$ and $24^{\circ}C$; and finally, two feeding frequency experiments for 93- and 100-g at $15^{\circ}C$ and $20^{\circ}C$ were conducted. Twenty fish averaging $5.5{\pm}0.2$ g ($mean{\pm}SD$) were randomly distributed into 18 indoor tanks containing 40-L seawater from a semi-recirculation system. Fish were fed a commercial diet for 4 weeks at water temperatures of $17^{\circ}C$ and $20^{\circ}C$. Two feeding trials were conducted to determine the optimum feeding frequency in growing Korean rockfish reared at temperatures of $15^{\circ}C$ and $19^{\circ}C$. Broken line regression analysis of weight gain (WG) indicated that the optimum feeding rates of 5-g growing Korean rockfish were 4.48% (BW/day; BW, body weight) at $17^{\circ}C$ and 4.83% (BW/day) at $20^{\circ}C$. Broken line regression analysis of WG showed optimum feeding rates of 16-g juvenile Korean rockfish of 3.41% (BW/day) at $16^{\circ}C$, 3.75% (BW/day) at $20^{\circ}C$, and 3.34% (BW/day) at $24^{\circ}C$. The biological performance, results, along with morphological indices and serological characteristics, suggest that a feeding frequency of 1 meal/day was optimal to improve WG in growing Korean rockfish grown from 93 to 133 g at a water temperature of $15^{\circ}C$, and 100 to 132 g at $19^{\circ}C$.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.338-348
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• 2017

Protein hydrolysates derived from plants and animals having antioxidant, suppression of hypertension, immunodulatory, alleviation of pain, and antimicrobial activity has been known as playing important role like hormone. This study was performed to optimize the hydrolysis of protein of sea of cucumber by a flavourzyme. The ranges of processes were the reaction temperature of 40 to $60^{\circ}C$, pH 6 to 8, and enzyme concentration 0.5 to 1.5%(w/v). As a result, the optimization of process was determined at temperature of $48-50^{\circ}C$, pH of 7.0-7.2, and enzyme concentration of 1.0-1.1%(w/v), and degree of hydrolysis was 43-45 at above conditions. The molecular weight of hydrolysate was distributed to 500-3,500 Da and showed typical peptides. Inhibition concentration ($IC_{50}$) of peptides of DPPH radical scavenging activity, Superoxide anion radical scavenging activity, Hydroxy radical scavenging activity, $Fe^{2+}$ cheating activity was 1.25, 3.40, 10.3, and 22.11 mg/mL, respectively. Therefore, we expect that those products are useful as functional food ingredients.

• Korean Journal of Plant Resources
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• v.28 no.4
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• pp.487-510
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• 2015

This study was carried out to inventory the vascular plant flora in Deokjeokdo and its adjacent regions (Mungapdo, Soyado), Ongjin-gun, South Korea, from April to October 2014. Based on the voucher specimens, vascular plants in this area consisted of 108 families, 362 genera, 578 species, 5 subspecies, 66 varieties and 4 forms, totally 653 taxa. In the flora of this area, 5 taxa of Korean endemic plants were found distributed in the sites, including Hepatica insularis Nakai and Asarum glabrata (C.S.Yook & J.G.Kim) B.U.Oh. Korean rare and endangered plants found in this area were 1 taxa of Critical Endangered Species (CR) and 5 taxa of Vulnerable Species (VU). The floristic regional indicator plants found in this area were 67 taxa comprising 3 taxa of grade V, 2 taxa of grade IV, 12 taxa of grade III, 3 taxa of grade II and 47 taxa of grade I. Naturalized plants consisted of 67 taxa, such as Chenopodium album L. and Erigeron annuus (L.) Pers. were recognized widely distributed in the area.

• Herbal Formula Science
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• v.24 no.4
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• pp.323-333
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• 2016

Objectives : The purpose of this study was to investigate musk deer in taxonomic status and genus species. We investigated the characteristic of musk deer for medicinal usages. Methods : To identifications of musk deer on the taxonomic status and genus species, the literary investigation were conducted on the Korean, China, and Japan pharmacopoeia and published herbal books, CITES Species Lists too. Results : Musk deer placement in a separate family status is the Moschidae. M. chrysogaster Hodgson and M. sifanicus Przewalski was the same species. So, Alpine musk deer revised M. chrysogaster Hodgson[=M. sifanicus Przewalski]. Geographic distribution of M. moschiferus L. divided Sibirica group and himalaica group. Group himalaica contains three subspecies: Korean musk deer(M. moschiferus parvipes Hol.), Chinese musk deer(M. chrysogaster Hodgson), and Himalayan musk deer(M. leucogaster Hodgson). The genetic divergence between M. moschiferus L. and other species was clearly distinguished from the others. M. berezovskii Flerove was less than the others. However, the divergence among M. chrysogaster Hodgson, M. fuscus Li, and M. leucogaster Hodgson were quite low. Musk deers are mostly distributed around the high-plateau. Moschus were from Nepal, Bhutan, Russia, China. Forest musk deer(M. berezovskii Flerove) farming was conducted in China from 1950s. In the Korean hebal pharmacopoeia, Moschus include l-muscone($C_{16}H_{30}O$ : 238.40) over 2% for quantitative test. Conclusions : There are three species of musk deer, Siberian musk deer(M. moschiferus L.), forest musk deer(M. berezovskii Flerove), and Alpine musk deer(M. chrysogaster Hodgson) for medicinal usages.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.5
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• pp.17-35
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• 2011

The purpose of this study is to offer the raw data for management and conservation of national park by systematic and objective surveying and analysing the flora distributed in the Hwarang district, Gyeongju national park. The results are as follows. The vascular plants in this site were summarized as 396 taxa: 95 families, 272 genera, 351 species, 2 subspecies, 38 varieties and 5 forma. The rare plants designated by Korea Forest Service were 5 taxa: Exochorda serratifolia S.Moore, Potentilla discolor Bunge, Prunus yedoensis Matsum, Lysimachia coreana Nakai and Inula salicina var. asiatica Kitam.. The korean endemic plants were 6 taxa: Populus tomentiglandulosa T.B.Lee, Clematis trichotoma Nakai, Lespedeza maritima Nakai, Lysimachia coreana Nakai, Forsythia koreana (Rehder) Nakai and Weigela subsessilis (Nakai) L.H.Bailey. The specific plants by floristic region were 30 taxa: Asplenium sarelii Hk., Salix chaenomeloides Kimura, Lysimachia barystachys Bunge, Achillea alpina L., Celtis aurantiaca Nakai, Vitex negundo var. incisa (Lam.) C.B.Clarke and so forth. The plants with approval for delivering oversea were 6 taxa: Clematis trichotoma Nakai, Exochorda serratifolia S.Moore, Glycine soja Siebold & Zucc., Lespedeza maritima Nakai, Lysimachia coreana Nakai and Weigela subsessilis (Nakai) L.H.Bailey. The naturalized plants were 49 taxa: Bilderdykia dumetora (L.) Holub, Descurainia pinnata Britton, Oxalis corymbosa DC., Bidens frondosa L., Panicum dichotomiflorum Michx. and so forth. The invasive alien plants were 2 taxa: Ambrosia artemisiifolia L. and Aster pilosus Willd. In future, if we will survey the flora of whole Gyeongju national park, we will offer the help to establishing the conservation plan of ecosystem in Gyeongju national park.