• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.288-293
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• 2018

This study was conducted to understand the characteristics of the seasonal and regional distribution of phytoplankton communities in the Fisheries Resources Protection Area of Korea (FRPA). We investigated the phytoplankton composition, abundance and dominant species collected from five different regions (Cheonsu, Tongyeong-I, Tongyeong-II, Hansan, and Jindong) in 2016. According to the results, most environmental parameters, such as temperature, salinity and nutrients, showed statistically significant seasonal differences. Suspended particulate material (SPM) only showed a statistically significant regional difference. The mean abundance of phytoplankton ranged from 13 to $4,062cells{\cdot}ml^{-1}$, with large spatio-temporal fluctuations. In particular, the bloom of phytoplankton (>$10^3cells{\cdot}ml^{-1}$) in Cheonsu Bay occurred in April and October with Skeletonema spp. and Chaetoceros socialis being the dominant species during these two seasons, respectively. The dominant species in the FRPA were diatoms (Pseudo-nitzschia spp., Skeletonema spp., and Chaetoceros pseudocriniuts) and dinoflagellates (Scrippsiella trochoidea and Tripos furca). The seasonal distribution of phytoplankton communities showed typical characteristics of coastal waters, i.e., that diatoms usually dominated in winter and autumn, while dinoflagellates tended to dominate in spring and summer. Meanwhile, the dominance rate of diatoms in the phytoplankton community in Cheonsu Bay, which is located in a high-turbidity region, was 9~27 % greater than that of diatoms in the phytoplankton community found in the south coastal waters, which is a low turbidity region.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.590-598
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• 2015

Despite various control methods for pine wilt disease, the disease has been increasing at an alarming rate every year in Korea. Still there is a lack of research on the problems of the current methods used to curb the disease. One main method to control pine wilt disease is fumigation for eliminating the larva of the pine sawyer beetle (Monochamus alternatus) which is known as the vector insect for pine wilt disease. We surveyed and analyzed the amount of destroyed uninfected trees in the fumigated area by studying 32 survey plots ($100m^2$) in Miryang city. The destroyed trees' crown area was estimated by induced regression between root collar area and crown area of the remaining trees (coniferous tree: $R^2=57.4$, deciduous broad-leaved tree: $R^2=63.8$). According to the analysis results, the infected trees (cut trees) were 18.7% and cut trees which were not infected were 35.5% of the total tree population of the study area on the basis of total crown area. In case of pine trees, 8.4% of uninfected trees were cut off but 62% of uninfected deciduous broad-leaved trees including Quercus spp. were affected and damaged during the fumigation process. Since these broad-leaved trees dominate the sub-canopy layer of the forest, this indiscriminate interruption of broad-leaved trees has the adverse effect of depriving the public benefits such as shadow, a cooler weather, controlling humidity, etc.

• The Journal of the Petrological Society of Korea
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• v.8 no.3
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• pp.171-182
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• 1999

The Myeonbongsan caldera, 10.2X8.0 km, developed within older sequences of sedimentary formations and intermediate composition volcanis in the southern Cheongsong area. Volcanic rocks in the caldera block include lower intermediate volcanics, middle tuffaceous sequences and upper silicic ones. The silicic volcanics, which is named Myeonbongsan Tuff, are composed of crystal-rich ash-flow tuff(300 m) , bedded tuff(30 m) and pumice-rich ash-flow tuff(700 m) in ascending order. Several intrusions dominate the early sequences within the caldera. The caldera collapsed in a trapdoor type when silicic ash-flow tuffs erupted fro major vent area in the caldera. Normal faulting along a ring fault system except the southwestern part dropped the tuffs down to the northrase with a maximum displacement of about 820 m. The Myeonbongsan Tuff is just about 1,030 m thick inside the northeastern caldera, with its base not exposed, and southwestward thinning down. Rhyolitic plug and ring dikes are emplaced along the central vent and the caldera margins, and the ring dikes are cut by plutonic stocks in the southeastern and northwestern parts. The caldera volcanism eviscerated the magma chamber by a series of explosive eruptions during which silicic magma was erupted to form the Myeonbongsan Tuff. Following the last ash-flow eruption, collapse of the chamber roof resulted in the formation of the Myeonbongsan caldera, a subcircular trapdoor-type depression subsiding about 820 m deep. After the collapse, stony to flow-banded rhyolites were emplaced as circular plugs and ring dikes along the central vent and the caldera margins respectively. Finally after the intrusions, another plutons were emplaced as stocks outside the caldera.

• Korean Business Review
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• v.18 no.1
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• pp.59-79
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• 2005

recently, world is progressing large quantity consumption with continuous Innovation and economic growth and pollution is accelerated at these process. Increase of industry activity and service that is point of corporation activity is discharging environmental pollutants at whole process to manufacture of end product and exhaust process from acquisition of raw material for accompanied product production hereupon. At the same time, being promoting resources consumption by that use much raw material, As a result, is becoming obstacle factors in sustainable development. So, corporation's responsibility for environmental protection is emphasized. Corporation which must prepare in green round or environmental problems should consider environmental effects that is happened over whole life of products that include waste treatment after raw material acquisition and use as well as selling end product simply. A Life Cycle Assessment techniques is normalized and standardized in International Standard Organization for technical committee 207(TC 207) world widely, and effort to apply in corporation's activity because mastering LCA techniques in domestic several corporations is undergone actively. Coming into effect of Kyoto's Protocol and International Organization for Standard 14000 series revision are presenting new survival principle in competition between country or corporation. LCA technique may become very useful means to corporation which wish to attempt environment management in real condition that awareness for environment is important. Also, An LCA to each product is going to cause big effects in corporation's whole image as well as competitive power raising for single product. Therefore, this research wishes to examine some instances for the future competitive product development at the estimation of environmental friendliness using LCA techniques and more theoretical considerations of the LCA techniques that can dominate corporation's fate.

• Journal of the Korean Geographical Society
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• v.50 no.4
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• pp.431-449
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• 2015

Philosophical roots and discussion frames of neoliberalism are very heterogeneous and approaches to neoliberalism including anarchism, post-neoliberalism also take diverse stances. Even if neoliberalism is losing legitimacy and stability through the global financial crisis, 2008, spatial perspective is becoming more and more important as neoliberalism constantly evolve with creating immense variations. Especially, urban space has become strategically crucial arenas as spatio-temporal strategies and generative nodes for reproduction of neoliberalism. Urban enclosure plays a key role in the specific process of neoliberal urbanization as a kind of capitalist formal and real subsumption. Contemporary capitalism continuously has been sustaining the accumulation by dispossession based on urban enclosure through reshaping the primitive accumulation mechanism. These enclosures are embodied by the change of public use concept from public ownership to economic benefits and public-private taking for private capital. Urban enclosure promotes reification deepening the separation and alienation of workers from the means of production and survival, and interdiction from free place appropriation, transformation of urban economy to patrimonial forms. Also it is pervasive in a daily life space and everyday experience in the city, and private tangled social rules dominate public space and the publicity of space.

• International Commerce and Information Review
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• v.14 no.4
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• pp.491-516
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• 2012

The purpose of this study is to research the situation of Technical Barriers of Trade(TBT) between Korea and China and analyze a pending issue such as a regular TBT notifications and specific trade concerns informed to WTO/TBT committee by Korea and China and seek the Countermeasures for Technical Barriers of Trade in Korea-China FTA. Generally, in case of a regular TBT notifications, "a protection of human health or safety" and "protection of the environment" are drawn a main articles from TBT committee data. And in case of a specific trade concerns, "international standard" and "transparency" are drawn a important factor from the said data. Henceforth those kinds of articles shall be an issuable matters for negotiation of Technical Barriers of Trade in Korea-China FTA. The results of the study indicate mainly that as Countermeasures of Korea for Technical Barriers of Trade in Korea-China FTA, Korean government level requires to withdraw an exclusive technical regulation of China and supports to improve Chinese technology for safety of products. Korean enterprises should develop products to meet an environment regulation and Korean government should support finance incentive, tax incentive to enterprises. Besides, regarding new international standard it is necessary for Korean side to dominate a relative regulation. First of all, it is important to secure a strength of capability and human resource for international standard activity. For improving a conveyance of notification information and transparency between Korea and China, it is efficient to establish a mutual direct network of notification.

• Journal of Radiation Protection and Research
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• v.16 no.2
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• pp.27-39
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• 1991

The diffusion of Sr-85, Cs-137, Co-60 and Am-241 in compacted domestic bentonite was studied, using a diffusion cell unit in which diffusion took place axially from the center of cylindrical bentonite sample body. The effects of compaction density and heat-treated bentonite on diffusion were analysed. And the diffusion mechanism of radionuclide was also analysed by evaluating the measured diffusivity of anion Cl-36. The apparent diffusivities obtained for Sr-85, Cs-137, Co-60 and Am-241 were $l.07{\times}10^{-11},\;6.705{\times}10^{-13},\;l.226{\times}10^{-13}\;and\; l.310{\times}10^{-14}m^2/sec$, respectively. When the as-pressed density of bentonite increased from $1.8\;to\;2.0g/cm^3$, the apparent diffusivity of Cs-137 decreased by quarter. In the case of bentonite heat-treated to $150^{\circ}C$, no significant change in diffusivity was observed, which showed the possibility that the domestic bentonite could be used as a chemical barrier to retard the radionuclide migration at below $150^{\circ}C$. From the calculated pore and surface diffusivity, the surface diffusion due to the concentration gradient of radionuclide sorbed on the solid phase was found to dominate greatly in total transport process.

• Journal of Ginseng Research
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• v.44 no.1
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• pp.86-95
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• 2020

Background: Ginsenoside Rb1 (Rb1), one of the most abundant protopanaxadiol-type ginsenosides, exerts excellent neuroprotective effects even though it has low intracephalic exposure. Purpose: The present study aimed to elucidate the apparent contradiction between the pharmacokinetics and pharmacodynamics of Rb1 by studying the mechanisms underlying neuroprotective effects of Rb1 based on regulation of microflora. Methods: A pseudo germ-free (PGF) rat model was established, and neuroprotective effects of Rb1 were compared between conventional and PGF rats. The relative abundances of common probiotics were quantified to reveal the authentic probiotics that dominate in the neuroprotection of Rb1. The expressions of the gamma-aminobutyric acid (GABA) receptors, including GABAA receptors (α2, β2, and γ2) and GABAB receptors (1b and 2), in the normal, ischemia/reperfusion (I/R), and I/R+Rb1 rat hippocampus and striatum were assessed to reveal the neuroprotective mechanism of Rb1. Results: The results showed that microbiota plays a key role in neuroprotection of Rb1. The relative abundance of Lactobacillus helveticus (Lac.H) increased 15.26 fold after pretreatment with Rb1. I/R surgery induced effects on infarct size, neurological deficit score, and proinflammatory cytokines (IL-1β, IL-6, and TNF-α) were prevented by colonizing the rat gastrointestinal tract with Lac.H (1 × 10⁹ CFU) by gavage 15 d before I/R surgery. Both Rb1 and Lac.H upregulated expression of GABA receptors in I/R rats. Coadministration of a GABA_A receptor antagonist significantly attenuated neuroprotective effects of Rb1 and Lac.H. Conclusion: In sum, Rb1 exerts neuroprotective effects by regulating Lac.H and GABA receptors rather than through direct distribution to the target sites.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.4
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• pp.213-221
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• 2018

South Korea has been reluctant to open its geospatial information overseas to ensure security as a divided country. However, this cannot continue as the domestic and international environments related to geospatial information and the industrial ecosystem of information and communication technologies have been changing dramatically. Within this context, this study aims to analyze the causal relations among relevant variables and how they change and interact with time using a systems thinking process. First, causal maps were created for the domains of national security, map-based convergence service, and corporate competition. Then, the causal maps for each domain were integrated, based on which the points for policy intervention and dominant feedback loops were identified. The analysis results showed that securing the self-sufficiency of domestic geospatial businesses is a key element to determine the whole causal map, and the variable that changes the dominant feedback loop from a vicious circle to a virtuous one is the decision to open geospatial information overseas. In this study, I found the policy leverage that is a policy intervention point that can produce a great effect with little input by building a causal map of the interactions between major variables. This study is significant in that it identified and analyzed the dominant feedback loop as to which causal structure would dominate the system in the long term. The results of this study can be used to discuss not only the impacts of map data overseas opening on the national security and geospatial information industry, but also the interactions in the future when Google or other global companies request to release the geospatial information.

• Journal of Life Science
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• v.17 no.11
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• pp.1517-1522
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• 2007

Gap junction channels formed by two adjacent cells allow the passage of small molecules up to ${\sim}\;1\;kDa$ between them. Hemichannel (connexon or half of gap junction) also behaves as a membrane channel like sodium or potassium channels in a single cell membrane. Among 26 types of connexin (Cx), $Cx32^*43E1$ (a chimera in which the first extracellular loop of Cx32 has been replaced with that of Cx43), Cx38, Cx46, and Cx50 form functional hemichannels as well as gap junction channels. Although it is known that Xenopus oocytes express endogenous connexin 38 (Cx38), its biophysical characteristics at single channel level are poorly understood. In this study, we performed single channel recordings from single Xenopus oocytes to acquire the biophysical properties of Cx38 including voltage-dependent gating and permeation (conductance and selectivity). The voltage-dependent fast and slow gatings of Cx38 hemichannel are distinct. Fast gating events occur at positive potentials and their open probabilities are low. In contrast, slow gatings dominate at negative potentials with high open probabilites. Based on hi-ionic experiments, Cx38 hemichannel is anion-selective. It will be interesting to test whether charged amino acid residues in the amino terminus of Cx38 are responsible for voltage gatings and permeation.