• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.3169-3174
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• 2008

Future power plants will be required to adopt some type of carbon capture and storage (CCS) technologies to reduce their CO2 emissions. One of distinguished CCS techniques expected to resolve the green house effect is to apply the oxy-fuel combustion technique to power plant, and a lot of research/demonstration programs have been going on in the world. In this paper, CO2-capturing power plants based on gas turbine and oxy-fuel combustion are investigated over several types of configurations. As a prior step, simulation model for 500 MW-class combined cycle power plant was set and was used as a reference case. The efficiencies of several power plants was compared and the advantages and disadvanteges was investigated.

• Nuclear Engineering and Technology
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• 제41권3호
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• pp.327-334
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• 2009

Elastic wave is one of the most useful tools for non-destructive tests in nuclear power plants. Since the elastic properties are indispensable for analyzing the behaviors of elastic waves, they should be predetermined within an acceptable accuracy. Nuclear power plants are exposed to harsh environmental conditions and hence the structures are degraded. It means that the Young's modulus becomes unreliable and in-situ measurement of Young's modulus is required from an engineering point of view. Young's modulus is estimated from the group velocity of propagating waves. Because the flexural wave of a plate is inherently dispersive, the group velocity is not clearly evaluated in temporal signal analysis. In order to overcome such ambiguity in estimation of group velocity, Wigner-Ville distribution as the time-frequency analysis technique was proposed and utilized. To verify the proposed method, experiments for steel and acryl plates were performed with accelerometers. The results show good estimation of the Young's modulus of two plates.

• 한국연초학회지
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• 제33권1호
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• pp.1-7
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• 2011

Major diseases of tobacco plants were surveyed throughout the Korea in 2011. Mosaic, bacterial wilt and hallow stalk were most severe during the harvest season on not only flue-cured tobacco plants but also burley tobacco plants. On flue-cured tobacco plants, mosaic caused by potato virus Y were more severe than those by tobacco mosaic virus or cucumber mosaic virus. The mosaic caused by potato virus Y was severe at Yeongwol and Chungju. On burley tobacco plants, mosaic were more severe at Jeongeup and Gochang than those at Chungnam and Jeonnam. A negative correlation between the mosaic incidence and the precipitation was recognized. On the other hand, there was a positive correlation between the incidence of hallow stalk incidence of flue-cured tobacco plants in harvesting stage and the precipitation during June was recognized significantly.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.104-107
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• 1998

The studies for antithrombotic substances from medicinal plants in my laboratory were started from the studies on PAF-antagonistic substances from Korean medicinal plants. The screening studies of PAF-receptor binding antagonistic activity were conducted on the extracts of 300 Korean medicinal plants, 37 tropical medicinal plants, 20 mushrooms, and 30 vegetables. From the results of screening studies, it was possible to select two Korean medicinal plants, i.e. 1) the leaf of Biota orientalis and 2) the seed of Arctium lappa, and two tropical medicinal plants, i.e. 3) the rhizome of Alpinia officinarum and 4) the leaf of Ardisia crispa as the candidates for the activity guided isolation of PAF-antagonistic substances.

• 한국약용작물학회지
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• 제19권6호
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• pp.407-413
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• 2011

This study was analyzed and investigated to evaluate ecological distribution of medicinal plants in Miho Stream of Korea. Totality 463 taxa of vascular plants were appeared in lower part of Miho Stream. Medicinal plants were distributed 253 taxa, which were 54.6% of the total vascular plants appeared. Medicinal plants of official drug compendium(Korean pharmacopoeia) were 85 taxa. Medicinal plants were distributed most of the forest area, and followed field surrounding, stream surrounding and paddy surrounding respectively. The distribution of life form hemicryptophyte was the most frequent. Plant community of appearing area of medicinal plants was classified into Salix koreensis, Phragmites japonica, Echinochloa crusgalli, Artemisia selengensis, Miscanthus sacchariflorus, Setaria faberii, Panicum dichotomiflorum, Bidens frondosa, Humulus japonicus, Monochoria vaginalis var. plantaginea, Eleocharis kuroguwai, Erigeron acris, Pinus densiflora, Pinus rigida, Quercus acutissima, Quercus serrata, Robinia pseudoacacia and Castanea crenata community. Medicinal plants in plant communities that occur frequently were Humulus japonicus, Corylus heterophylla and Liriope spicata.

• 인간식물환경학회지
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• 제22권1호
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• pp.91-98
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• 2019

This study aimed to provide basic data on current trends in floriculture through a survey. The exhibitors' purposes and items displayed at the Tokyo International Flowers & Plants Expo in 2017 were surveyed. The survey was conducted among 238 exhibitors during the exhibition period from October 11 to 13, 2017. As a result, participants came from 14 countries including Belgium, China, Colombia, Japan, Korea and France. The purposes of the majority of the surveyed exhibitors were to display cultivars (86 exhibitors, 36.3%), followed by to display merchandise, subsidiary materials and cultivation techniques. Among cultivars, pot plants accounted for the majority of the entire cultivars (54 exhibitors, 55.1%), followed by cut flowers (35 exhibitors, 35.7%), sapling, and seeds. The most of the displayed pot plants were ornamental plants (27 exhibitors, 43.5%), followed by garden trees, ground cover plants, bedding plants and succulent plants. The most of the displayed cut flowers were rose (8 exhibitors, 21.1%), followed by lisianthus, chrysanthemum and dahila. In terms of cultivation techniques, those using moss were displayed by 7 exhibitors (50%) and green-wall techniques were displayed by 6 exhibitors (42.9%). In terms of merchandise, processed products were displayed by 21 exhibitors (41.2%), followed by floral products. Therefore, the IFEX can be used as a place to understand current trends in the floriculture market.

• 한국자원식물학회지
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• 제28권4호
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• pp.475-486
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• 2015

This survey was conducted in order to investigate the vascular plants of Hak Reservoir Valley in the DMZ Area, Korea. The vascular plants were collected six times (from April 2014 to November 2014) and consisted a total of 238 taxa; 69 families, 172 genera, 206 species, 2 subspecies, 26 varieties and 4 forms. The observed rare plant species as designated by Korea Forest Service were 3 taxa including Carex capricornis Meinsh. ex Maxim., Acorus calamus L., Penthorum chinense Pursh. Endemic plant species were 2 taxa including Salix koriyanagi Kimura, Clematis brachyura Maxim. 17 taxa were listed as specific plant species based on phytogeographical in the investigated area. 25 taxa were recorded as naturalized plants, and their Naturalization Ratio and Urbanization Index were recorded as 10.46%, and 7.78%, respectively. Of the 238 taxa listed; 105 were pasturing plants, 92 edible plants, 76 medicinal plants, 24 ornamental plants, 6 stain plants, 4 timber plants, 2 fiber plants, 2 industrial plants and 55 unknown plants.

• Corrosion Science and Technology
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• 제9권5호
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• pp.187-195
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• 2010

Hyper duplex stainless steels have been developed in Korea for the purpose of application to the seawater system of Korean nuclear power plants. This system supplies seawater to cooling water heat exchanger tubes, related pipes and chlorine injection system. In normal operation, seawater is supplied to heat exchanger through the exit of circulating water pump headers, and the heat exchanged sea water is extracted to the discharge pipes in circulating water system connected to the circulating water discharge lines. The high flow velocity of some part of seawater system in nuclear power plants accelerates damages of components. Therefore, high strength and high corrosion resistant steels need to be applied for this environment. Hyper duplex stainless steel (27Cr-7.0Ni-2.5Mo-3.2W-0.35N) has been newly developed in Korea and is being improved for applying to nuclear power plants. In this study, the physical & mechanical properties and corrosion resistance of newly developed materials are quantitatively evaluated in comparative to commercial stainless steels in other countries. The properties of weld & HAZ (heat affected zone) are analyzed and the best compositions are suggested. The optimum conditions in welding process are derived for ensuring the volume fraction of ferrite(${\alpha}$) and austenite(${\gamma}$) in HAZ and controlling weld cracks. For applying these materials to the seawater heat exchanger, CCT and CPT in weldments are measured. As a result of all experiments, it was found that the newly developed hyper duplex stainless steel WREMBA has higher corrosion resistance and mechanical properties than those of super austenitic stainless steels including welded area. It is expected to be a promising material for seawater systems of Korean nuclear power plants.

• 농업생명과학연구
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• 제50권5호
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• pp.1-9
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• 2016

Plant growth and development strongly influenced by light quantity and its spectral composition. Young tomato plants were cultivated in growth cabinets under artificial light provided by red and blue light emitting diodes(LEDs) during 12 hours, then plants were exposed to monochromatic ultraviolet, blue, green and red lights as an end-of-day(EOD) treatment during 4 hours to study their effect on plant growth parameters. EOD lighting from various LEDs increased total fresh and dry weights as well as assimilation area compared to those in control. Blue light increased stem height, internode length and stem diameter. Monochromatic UV-A light reduced stem elongation, highly increased stomatal conductance. Compactness and health index of young tomato plants were increased in UV-A and red light treatments.

• 한국환경과학회지
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• 제19권4호
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• pp.459-481
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• 2010

This study was carried out to investigate the vascular flora of Mt. Munsu. The vascular plants collected in 13 times(from Mar. to Oct. 2009) were identified as 511 taxa in total, including 113 families, 332 genera, 445 species, 5 subspecies, 46 varieties, 5 forms. Among them, 6 taxa of the Korea Forest Service-designated rare & endangered plants and the Korean endemic plants were identified as 2 taxa. Based on the list of approved for delivering overseas of plants, 6 taxa were recorded in the investigated area. The Ministry of Environment-designated plants, which should be protected by the wildlife protection law, were identified as 2 taxa and 39 taxa of specially designated plants by the Ministry of Environment. The naturalized plants were identified as 53 taxa, and their naturalization ratio and urban index were found to be 10,3%, and 18.5% respectively. There existed many kinds of plants resources having conservational value like Ranunculus trichophyllus var. kadzusensis, Jeffersonia dubia etc, in this area, but there remains a fear of nature destruction's acceleration due to indiscriminate human development and access of a lot of visitors, so it is judged that there should be a management plan, such as a limit on the number of visitors or rest-year-system for restoration of nature.