• Journal of Radiation Protection and Research
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• v.34 no.3
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• pp.151-154
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• 2009

The Radiation Emergency Plan (REP) can be divided into a technical and an administrative responses. The domestic NPP's REPs are reviewed from the viewpoint of the administrative response and improvement methods are also suggested in this treatise. The fields of the reviews are the composition of the emergency response organizations, the activation criteria of the organizations, the selection of the staffings and the reasonableness of the REP's volume. In addition, the limitations of the current radiation exercises are reviewed and the improvement method of the exercise is presented. It is expected that the suggested recommendations will be helpful in establishing useful REPs and making practical radiation exercises in Korea.

• Journal of the Korean Ceramic Society
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• v.34 no.10
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• pp.1074-1082
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• 1997

Microstructure and permeability as a function of sintering temperature and composition were studied on the Ni$\delta$Cu0.4-$\delta$Zn0.6Fe2O4 ($\delta$=0, 0.1, 0.2, 0.3, 0.4) which was prepared by Cu2+ substitution for Ni2+ in Ni.0.4Zn0.6Fe2O4, then followed by 8 wt% CuO and 1wt% Bi2O3 as sintering aids. It was found that NiCuZn ferrite in which Cu2+ is substituted for Ni2+ is more effective in reduction of sintering temperature than Ni.0.4Zn0.6Fe2O4, containing CuO as a sintering aid. The specimen $\delta$=0.2 sintered at 90$0^{\circ}C$ for 2hr exhibited the highest initial permeability value ($\mu$o=280 at 1Mhz), but the real permeability decreased at the frequency under 10 MHz. EPMA analysis showed that Ni$\delta$Cu0.4-$\delta$Zn0.6Fe2O4 ($\delta$=0.4), sintered at 95$0^{\circ}C$ for 2hrs consisted of three phase regions of Ni.0.3Cu0.1Zn0.6Fe2O4 region, Cu and Bi liquid existed at the 3-point boundary, although the stabilization energy of Ni2+ is higher than that of Cu2+ in B site.

• Journal of the Korean Ceramic Society
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• v.25 no.6
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• pp.571-576
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• 1988

The microstructure and electrical properties of 0.02Pb[Cd1/2W1/2)O3-0.505PbZrO3-0.475PbTiO3 with MnO2 addition have been investigated. The amount of MnO2 addition was 0, 0.2, 0.4, 0.6, 0.8, 1wt%, respectively. When MnO2 is added up to 0.2wt%, Mn3+ which is substituted for Ti4+ site make hole and act as a acceptor. When MnO2 is added over 0.2wt% Mn3+ which is substituted for Cd2+ site create electron and act as a donor. The variation of grain size show that it was rapidly increased by 0.4wt% addition of MnO2, and while that in the range of over 0.6wt% addition of MnO2 it was decreased. The solid solution range of MnO2 that assumed in this composition according to the variations of microstructure and electrical properties was 0.4-0.6wt%.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.2
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• pp.42-49
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• 2001

This design proposal was presented to a design competition for renovation of the Pagoda Park, located in Chongro-2ga, Chongro-gu, Seoul, where the first ˝Manse˝ (hurrah) Movement fighting against Japanese colonization, broke out on March 1st, 1919. The park has been considered to be the first modern park in Korea also. The objectives for the design were to make a sacred place to commemorate the 3.1 ˝Manse˝ Movement, to preserve and symbolically memorialize historic remains of the old ˝Wongaksa˝ Temple, an to provide natural and rest areas for citizen. For the space composition, three axes symbolic of, ´freedom and independence´, ´mercy´, and ´nature´, were created. For the freedom and independence axis, exiting facilities, such as statures and monuments related to the 3.1 Movement, were relocated centering around the octagonal pavilion, which was the starting point for the movement, to give order of the site. For the ercy axis, symbols of traditional temple structures, such as, ´Iljugate´-´Pian bridge´-´Chongwang gate´-´Haetal gate´-Pagoda-Buddhist sanctum, were created to symbolize the temple remains and placeness. For the nature axis, tree groves, walking trails, and rest areas for citizen were provided around the site. As a whole the design provided structural orders from secular spaces outside to sacred spaces inside.

• Korean Journal of Microbiology
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• v.28 no.3
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• pp.204-209
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• 1990

The total and heterotrophic bacterial distributions, compositions and alkaline phosphatese actibities were analyzed in Lake Soyang from Sep. 1987 to Aug. 1988. The heterotrophic bacteria was small portion, 0.07-2.63% of total bacterial number which ranged from $3.2{\times}10^{5}$ to $3.2{\times}10^{6}$ cells/${\mu}\ell$. The composition of bacterial community was less diverse in summer and at the fish farm site and Peridinium blooming site. Pseudomonas and Flavo bacterium were the dominant genera in all sites. The highest proportion and activity of alkaline phsophatase was appeared in Flavobacterium, while Pseudomonas was the most predominant group.

• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.331-337
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• 2015

$LaBO_3$ (B = Cr, Mn, Fe, Co, and Ni) perovskites, the most common perovskite-type mixed ionic-electronic conductors (MIECs), are promising candidates for intermediate-temperature solid oxide fuel cell (IT-SOFC) cathodes. The catalytic activity on MIEC-based cathodes is closely related to the bulk ionic conductivity. Doping B-site cations with other metals may be one way to enhance the ionic conductivity, which would also be sensitively influenced by the chemical composition of the dopants. Here, using density functional theory (DFT) calculations, we quantitatively assess the activation energies of bulk oxide ion diffusion in $LaBO_3$ perovskites with a wide range of combinations of B-site cations by calculating the oxygen vacancy formation and migration energies. Our results show that bulk oxide ion diffusion dominantly depends on oxygen vacancy formation energy rather than on the migration energy. As a result, we suggest that the late transition metal-based perovskites have relatively low oxygen vacancy formation energies, and thereby exhibit low activation energy barriers. Our results will provide useful insight into the design of new cathode materials with better performance.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.197-201
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• 2009

A lot of work is carried out concerning to acicular ferrite formation in the weld metal of high strength and low-alloy steel. Those results are suggesting that oxides that contain titanium elements provides nucleation site of intragranular ferrite, referred as acicular ferrite. Thus, when intragranular ferrite is expected to form in heat-affected zone, oxide containing titanium element should be formed in the steel. However, normal steel is deoxidized by using aluminum element (Al-killed steel) with little oxygen content. It means almost oxygen is deoxidized with aluminum elements. In the present work, in order to form the acicular ferrite in the heat affected zone, with the same concept in the case of weld metal, the steel deoxidized with titanium element (titanium killed-steel) is prepared and the acicular ferrite formation is observed in detail by using laser-conforcal microscopy technique. The confocal technique makes it possible that the morphological change along the phase transformation from austenite to ferrite is in-situ tracked. Thus, the inclusion that stimulated the ferrite nucleation could be directly selected from the observed images, in the HAZ of the Ti-killed steel. The chemical composition of the selected inclusion is analyzed and the nucleation potential is discussed by changing the nucleation site with boron element. The potency for the ferrite nucleation is summarized and the existence of effective and ineffective manganese sulfide for nucleation is made clear.

• Animal cells and systems
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• v.15 no.2
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• pp.169-177
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• 2011

In August 2002, a heavy rainfall (445 mm in total for 5 consecutive days) resulted in a catastrophic flood, and it completely washed away the benthic fauna from the mainstream channel of the Gapyeong stream, a typical mid-sized stream in the central Korean peninsula. This study was to investigate the recovery patterns of aquatic insect communities that were damaged by the flood. Aquatic insects were sampled quantitatively using a Surber sampler ($50{\times}50$ cm, 1 riffle and 1 pool/run habitats per site) from three sites (4th-6th order) of the Gapyeong stream prior to 2000 and seasonally after the flood event from 2003 to 2006. Before the flood in the reference year (2000), a total of 77 species of aquatic insects were collected, whereas after the flood 47 species (2003), 51 species (2004), 64 species (2005) and 55 species (2006) were collected from the whole sampling sites. The aquatic insect density decreased to 26.85% (2003), 90.25% (2004), 52.53% (2005) and 54.95% (2006) of that recorded in the reference year. Although approximately 70% of the aquatic insect fauna has recovered since the flood event, the species composition in the most recent year differed substantially (similarity ca. 50%). On the other hand, the compositions of functional groups have not significantly changed. Aquatic insect communities at the riffle sites were affected more profoundly than those at the pool/run sites. The aquatic insect communities at the upstream site recovered more rapidly than those at the downstream sites.

• Archives of Plastic Surgery
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• v.48 no.1
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• pp.10-14
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• 2021

Soft tissue filler injections are widely used due to their immediate effects, predictable results, and high stability. However, as the use of soft tissue filler injections has increased, various complications have been reported. We report a life-threatening complication in a patient who developed sepsis and necrotizing fasciitis. A 45-year-old woman presented with right leg pain and discharge from the labia majora. The patient had received a soft tissue filler injection of unknown composition 1 year earlier and had recently undergone incision and drainage for an inflammatory cystic nodule. Antibiotic treatment was administered for cellulitis, but the infection progressed to necrotizing fasciitis and sepsis. Fasciotomy and intensive care unit treatment improved the systemic infection, but the soft tissue filler injection site did not respond to treatment for 1 month. Thus, the injection site was covered with a pedicled vertical rectus abdominis musculocutaneous flap after wide excision. The area of skin necrosis on the leg was covered with split-thickness skin grafts. Infections occurring after soft tissue filler injections are related to biofilms, and treatment is sometimes difficult. Therefore, although soft tissue filler injections have a favorable safety profile, it is important to be aware of the risk of life-threatening complications.

• Journal of Ecology and Environment
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• v.45 no.4
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• pp.218-227
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• 2021

Background: Artificial light at night has recently been identified as a major factor adversely affecting global insect diversity. Here, we compared the insect diversity in Gwangneung Forest Biosphere Reserve, specifically in the Korea National Arboretum (with no artificial light at night), with that of three nearby urban sites with a gradient of artificial light at night (five locations at each site). We analyzed the effects of the artificial night lighting index, mean annual temperature, and field light intensity (lux) at night on the insect community structure. Results: The urban sites generally exhibited higher species richness and abundance as well as clear indicator species compared with the control site. The size distribution of the collected insects markedly differed between the control and the three urban sites. The abundance of herbivorous and omnivorous insects increased and decreased, respectively, with the increase in light intensity. Species richness of herbivorous and omnivorous insects was likely correlated with the field light intensity at night and artificial night lighting index, respectively. Conclusions: This study demonstrates the association between nighttime environment and marked changes in insect community structure and revealed consequent transition of ecosystem services by changes in trophic group composition.