• Journal of the Korean Geographical Society
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• v.48 no.4
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• pp.497-508
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• 2013

The objective of this study is to determine the spatiotemporal influences of climatic factors and atmospheric aerosol on phenological cycles of the Korea Peninsular on a regional scale. High temporal-resolution satellite data can overcome limitations of ground-based phenological studies with reasonable spatial resolution. Study results showed that phenological characteristics were similar among evergreen forest, deciduous forest, and grassland, while the inter-annual vegetation index amplitude of mixed forest was differentiated from the other forest types. Forest types with high VI amplitude reached their maximum VI values earlier, but this relationship was not observed within the same forest type. The phase of VI, or the peak time of greenness, was significantly influenced by air temperature. Aerosol optical thickness (AOT) time-series showed strong seasonal and inter-annual variations. Generally, aerosol concentrations were peaked during late spring and early summer. However, inter-annual AOT variations did not have significant relationships with those of VIs. Weak relationships between AOT amplitude and EVI amplitude only indicates that there would be potential impacts of aerosols on vegetation growth in the long run.

• Korean Journal of Environmental Biology
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• v.34 no.1
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• pp.8-17
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• 2016

Ecosystems have functions of providing, supporting, regulating and cultural services. In particular, there is an increasing attention to the importance of regulating ecosystem services in carbon sequestration function, since it is closely related to the issue of climate change. In this study, to quantify benefits of climate regulating ecosystem services, the carbon storage was defined as an indicator. Nine major Korean ecosystems were classified and research papers on carbon storage were analyzed. The collected carbon storage data were categorized according to classified ecosystems, methodologies, and carbon storage components. For each category, the mean, standard error and coefficient of variation were calculated. The carbon storage indicator was highest in vegetation biomass of deciduous forest ecosystems. The uncertainty was also estimated by the IPCC 2006 guidelines. The estimations of the uncertainty differed by methodologies and carbon storage components. With exception of forest ecosystems, the limited number of studies were available which might have hindered to conduct accurate estimations. These findings indicate that there are needs for further clarification in the measurement standards by different ecosystems.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.64-75
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• 2012

To predict the future distribution of forest vegetation, the present forest stand distributions of South Korea were represented by multinomial logit model with the following environmental variables: summer average precipitation, the coldest month average temperature, elevation, degree of base saturation, and soil organic matter. The future forest community was predicted by applying the MIROC3.2 hires A1B scenario. The future climate data were downscaled by statistically method. The coldest month average temperature increased $4.4^{\circ}C$, $6.0^{\circ}C$, and $9.4^{\circ}C$, and 3 months average precipitation changed -1.2%, 5.7%, and 5.3% for 2020s, 2050s, and 2080s respectively. For the projected summer precipitation and the coldest temperature, the future deciduous and mixed forests in the study area increased 56.9% and 8.3% and the coniferous forest decreased 11.2% in 2080s based on present.

• The Korean Journal of Ecology
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• v.28 no.1
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• pp.37-43
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• 2005

This study presents the Mid-Lateglacial vegetation history of southwestern Korea. From the result of AMS dating and pollen analysis, four local pollen assemblage zones(BS) were recognized. The four local pollen assemblage zones are BS 1. 12,222cal BC$\sim$9,160cal BC: cool-temperate northern/altimontane mixed coniferous & deciduous broad-leaved forest, BS 2. 9,160cal BC$\sim$ 4,210cal BC: cool-temperate central/montane deciduous broad-leaved forest, BS 3. 4,210cal BC$\sim$125cal BC: cool-Temperate southern/submontane mixed coniferous & deciduous broad-leaved forest. BS 4. BC125cal ${\sim}$present: warm-temperate/cool-temperate southern/submontane coniferous forest. Pine forest expanded since 4,210cal BC and full-scale rice cultivation might started since 2,120cal BC. A radical expansion of Pinus densiflora forest after postglacial stage might be caused by human impacts including full-scale agriculture.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.246-260
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• 2014

A 90-m horizontal-resolution numerical model was configured to study the micrometeorological features of local winds in the valley of Gwangneung KoFlux (Korea Flux network) Sites (GDK: Gwangneung Deciduous forest site in Korea, GCK: Gwangneung Coniferous forest site in Korea) during summer days. The U. S. Geological Survey (USGS) Shuttle Radar Topography Mission (SRTM) data were employed for high-resolution model terrain height. Model performance was evaluated by comparing observed and simulated near-surface temperature and winds. Detailed qualitative analysis of the model-simulated wind field was carried out for two selected cases which are a clear day (Case I) and a cloudy day (Case II). Observed winds exhibited that GDK and GCK, as well as Case I and Case II, had differences in timing, duration and strength of daytime and nighttime wind direction and speeds. The model simulation results strongly supported the existence of the drainage flow in the valley of the KoFlux tower sites. Overall, the simulated model fields realistically presented the diurnal cycle of local winds in and around the valley, including the morning drainage-upslope transition and the evening reversal of upslope wind. Also, they indicated the complexity of local winds interactions by presenting that daytime westerly winds in the valley were not always pure mountain winds and were often coupled with larger-scale wind systems, such as synoptic-scale winds or mesoscale sea breezes blowing from the west coast of the peninsula.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.73-87
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• 2018

A variety of micro meteorological variables such as air temperature, wind, solar radiation and latent heat at Gwangneung forests (conifer and broadleaved forests) and AWS (Automated Weather Station) of Pocheon urban area were used to quantify the air temperature reduction effect of forests, which is considered to be an eco-friendly solution for reducing the urban heat island intensity during summer. In June, July and August of 2016 and 2017, the average maximum air temperature differences between above and below canopy of forests, and between the forests and urban areas were $-1.9^{\circ}C$ and $-3.4^{\circ}C$ respectively, and they occurred at 17:00. However, there was no difference between conifer and broadleaved forests. The effect of air temperature reduction by the forests was positively correlated with accumulated evapotranspiration and solar radiation from 14:00 to 17:00 and showed a negative correlation with wind speed. We have developed a model to quantify the effect of air temperature reduction by forests using these variables. The nighttime air temperature reduction effect by forests was due to the generation of cold air from radiative cooling and the air temperature inversion phenomenon that occurs when the generated cold air moves down the side of mountain. The model was evaluated in Seoul by using 28 AWSs. The evaluation shows that the air temperature of each district in Seoul was negatively correlated with the area and size of the surrounding tall vegetation that drives vegetation evapotranspiration during the day. During the night, however, the size of the surrounding tall vegetation and the elevations of nearby mountains were the main influencing factors on the air temperature. Our research emphasizes the importance of the establishment and management of urban forests and the composition of wind roads from mountains for urban air temperature reduction.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.210-215
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• 2013

Litterfall production represents a major contribution of carbon and nutrient cycling in forest ecosystems. This study was carried out to determine the litterfall production in a broadleaved deciduous forest at the Mt. Keumsan Long Term Ecological Research (LTER) site, Southern Korea. Littefall was collected monthly or bimonthly from the site for 7 years from 2004 to2010. Leaf and reproductive (catkins) litters showed a seasonal variation, but litters of needle, branch, and barks were not changed across the seasons. Annual leaf litter of Quercus serrata and Carpinus laxiflora were significantly different (p<0.05) but that of C. cordata, Chamaecyparis obtusa, and Pinus thunbergii was not significantly changed for 7 years (p>0.05). Annual average litterfall production was 5,223 kg/ha, but annual variations were very large with minimum of 4,110 kg/ha/yr in 2004 and maximum of 6,002 kg/ha/yr in 2007. Total litterfall comprised of 2,323 kg/ha/yr in Q. serrata, 442 kg/ha/yr in C. laxiflora, 157 kg/ha/yr in C. cordata, 131 kg/ha/yr in Acer pseudosieboldianum, 390 kg/ha/yr in other deciduous tree species, 74 kg/ha/yr in P. thunbergii, 37 kg/ha/yr in C. obtusa, 672 kg/ha/yr in branches, 515 kg/ha/yr in miscellaneous, 448 kg/ha/yr in reproductive parts, and 54 kg/ha/yr in barks. respectively. The results indicate that litterfall production of the Mt. Keumsan LTER site was yearly fructurated with the positive linear relationship between leaf or total litterfall and annual mean temperature if no disturbance such as a typoon, and was lower than that of other Korean LTER sites.

• Food Science and Preservation
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• v.12 no.1
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• pp.43-47
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• 2005

Ligularia fischeri is widely grown in Korea and is containing medicinal components such as chamomile, jacobine, and ameleme etc.. Its juices from the leaf are well known for anticancer effect. This study was conducted to make Ligularia fischeri as functional food resources as food produce. To examine quality characteristics of Ligularia fischeri - such as color, texture, fiber, minerals, tannin, crude proteins, crude lipids and sensory quality - were determined using physicochemical methods. The content of dietary fibers were 0.56 g in each 100 g of freeze dried Ligularia fischeri. One of the mineral contents, iron showed the highest value. The contents of tannin were 33.3 ppm in fresh Ligularia fischeri. As results of food products having Ligularia fischeri, the content of crude protein were about $9.35\%$ and $10.37\%$ in rolling snack and garlic bread respectively. The content of crude lipid were about $28.27\%$ and $23.39\%$ in rolling snack and garlic bread, respectively. In sensory evaluation, garlic bread appeared better preference than rolling snack, and older age group showed a better acceptability.

• Journal of Life Science
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• v.19 no.8
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• pp.1164-1169
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• 2009

Aberrant DNA methylation plays an important role in the development of cancer. It has been reported recently that DNA hypermethylation is involved in the maintenance of cancer stem cells. The present study was designed to test the hypothesis that the demethylating agent, 5-aza-2'-deoxycytidine (AZA), can inhibit the potential for maintenance of cancer stem cells. To validate this hypothesis, we used 4T1 syngeneic mouse models of breast cancer. The AZA pre-treated 4T1 cells showed a dramatic inhibition of tumorsphere formation, compared to their counterparts in vitro. In addition, the AZA treatment significantly suppressed the expression of stem regulator genes, such as oct-4, nanog and sox2, compared to counterparts in vivo. Therefore, selective inhibition of DNA methylation may be useful for stem-specific cancer therapy.

• Journal of Technology Innovation
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• v.23 no.3
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• pp.21-42
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• 2015

This paper shows the case of the evolution of Korean e-Government services in the theoretical lens of Actor-Network Theory and Structuration Theory. It presents how human actors (i.e. presidents and the central administrations) and non-human actors (i.e. law, standards, and relay systems) have established as the one network together, and how this network affects the evolution of Korean e-Government services. This case demonstrates in public sector can adopt not only Actor-Network Theory, but also Structuration Theory to explain both micro and macro contexts. The practical implications are given especially for the developing countries in pursuing the rapid development process of e-Government services.