• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.32-40
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• 2006

The Ichthyofauna and fish community were studied in the lower course of Imjin River from April 2003 to October 2004. During the survey period 80 species belonging to 23 families were collected. Twenty-five species (31.1%) of them were Korean endemic species. Exotic fishes were Carassius cuvieri, Lepomis macrochirus and Micropterus salmoides, and they complied 1.3% of total catch. The species of Hemibarbus mylodon was identified as natural monument, and acheilognathus signifer, Pseudopungtungia tenuicorpa, Gobiobotia macrocephala and Gobiobotia brevibarba were endangered species. Migration fish were Coilia ectens, Anguilla japonica, Plecoglossus altivelis and Takifugu obscurus. Dominant species were Zacco platypus (St. 1), Microphysogobio yaluensis (St. 2), Hemibarbus labeo (St. 3, 4) and coilia ectens (St. 5). The lower course of Imjin River was more abundance of species, high diversity and richness, and lower dominance index than those of the lower course of Han River.

• Journal of Korean Neurosurgical Society
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• v.58 no.3
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• pp.175-183
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• 2015

Objective : Intracranial ruptured vertebral artery dissecting aneurysms (VADAns) are associated with high morbidity and mortality when left untreated due to the high likelihood of rebleeding. The present study aimed to establish an endovascular therapeutic strategy that focuses specifically on the angioarchitecture of ruptured VADAns. Methods : Twenty-three patients with ruptured VADAn received endovascular treatment (EVT) over 7 years. The patient group included 14 women (60.9%) and 9 men (39.1%) between the ages of 39 and 72 years (mean age 54.2 years). Clinical data and radiologic findings were retrospectively analyzed. Results : Four patients had aneurysms on the dominant vertebral artery. Fourteen (61%) aneurysms were located distal to the posterior inferior cerebellar artery (PICA). Six (26%) patients had an extracranial origin of the PICA on the ruptured VA, and 2 patients (9%) had bilateral VADAns. Eighteen patients (78%) were treated with internal coil trapping. Two patients (9%) required an adjunctive bypass procedure. Seven patients (30%) required stent-supported endovascular procedures. Two patients experienced intra-procedural rupture during EVT, one of which was associated with a focal medullary infarction. Two patients (9%) exhibited recanalization of the VADAn during follow-up, which required additional coiling. No recurrent hemorrhage was observed during the follow-up period. Conclusion : EVT of ruptured VADAns based on angioarchitecture is a feasible and effective armamentarium to prevent fatal hemorrhage recurrence with an acceptable low risk of procedural complications. Clinical outcomes depend mainly on the pre-procedural clinical state of the patient. Radiologic follow-up is necessary to prevent hemorrhage recurrence after EVT.

• Atmosphere
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• v.27 no.4
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• pp.435-444
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• 2017

By analyzing Asian Precipitation-Highly-Resolved Observational Data Integration Towards Evaluation (APHRODITE) from May to September for 1951~2007, this study investigates impacts of two dominant boreal summer intraseasonal oscillation (BSISO) modes on precipitation over Monsoon Asia including Korea and long-term change of 10~20-day and 30~60-day ISO over Korea. It is shown that BSISO strongly modulates rainfall variability over the many part of Monsoon Asia including Korea. Korea tends to have more (less) rainfall during the phases 3~5 (7~8) of BSISO1 representing the canonical northward/northeastward propagating 30~60-day ISO and during the phases 6~8 (3~5) of BSISO2 representing the northward/northwestward propagating 10~20-day ISO. It is found that the 10~20-day ISO variability contributes to summer mean rainfall variability more than 30~60-day ISO over Korea. For the 57 years of 1951~2007, the correlation coefficient between the May to September mean precipitation anomaly and standard deviation of 10~20-day (30~60-day) ISO is 0.71 (0.46). It is further noted that there is a significant increasing trend in the 10~20-day and 30~60-day ISO variability in the rainy season during the period of 1951 to 2007.

• Ocean and Polar Research
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• v.33 no.4
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• pp.421-434
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• 2011

Although thermal effluent from coastal power plants affects marine ecosystems, few studies have examined the spatiotemporal distribution of macrobenthic communities in a coastal area of Korea with thermal discharge. This study analyzed the species composition and abundance of a macrobenthic community in relation to environmental variables for a period of 1 year. In total 334 macrobenthic faunal species were collected; the mean density was 3,221 ind/$m^2$. The number of species and the density of macrobenthic fauna increased with distance from the thermal discharge site. Cluster analysis indicated that the macrobenthic community could be divided into two groups: group I in shallow (< 30 m deep) and group II in the outer areas (> 30 m deep). Group I showed the lowest species density and diversity. Four polychaetes, including Magelona japonica, Spiophanes bombyx, Scolotoma longifolia and Chaetozone setosa, all of which have been dominant species since 1987, exhibited higher mean densities in the area distant from the thermal discharge (the outer and north areas). Conversely, the warm-adapted and opportunistic species, such as the amphipods Urothoe convexa and Mandibulophoxus mai, the bivalve Felaniella sowerbyi, and the polychaete Rhynchospio sp., were more abundant in the thermal discharge region. The results of this study indicate that thermal effluent influences macrobenthic communities in the shallow area, while other environmental variables, such as depth, sediment grain size, and TOC, are more important determinants of the macrobenthic communities in deeper regions (> 30 m deep).

• The Journal of Korean Physical Therapy
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• v.18 no.3
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• pp.79-87
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• 2006

Purpose: The present study purposed to examine induced characteristic or erythema and safety by medium wave ultra violet(UVB) lamp. Methods: We compared sunshine and UVB lamp using spectroradiometer and UV radiometer. For measuring sunshine irradiation, we used spectoradiometer and detected from 8 to 18 o'clock every each hour on the beach, playground and rooftop of a 5 story building. The subjects for erythema examination were 5 healthy subjects who have no pathologic history of photosensitivity reaction, psoriasis and vitiligo. They were exposed to UVB radiation at the abdominal area for 2 hours and after irradiation, we observed the change of skin color every 12 hours over a period of 1 week. Results: Between sunshine and UVB lamp, sunshine had higher data on the chromaticity coordinates, dominant and peak wavelength, bandwidth and purity than the UVB lamp but on the color temperature, brightness the UVB lamp had higher data than the sunshine. In comparison of sunshine and UVB lamp, UVB lamp irradiated constantly such as $3.9-4.4{\mu}W/cm^2$ at a distance of 100cm between bed and lamp which was same as early morning irradiation on the sunshine. The erythema didn't appear to any subject. Conclusion: This results suggest that the UVB lamp has lower irradiance as much as early sunshine. Therefore the UVB lamp had no influence of inducing erythema at a distance of 100cm between bed and lamp.

• Journal of Korean Society of Steel Construction
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• v.12 no.3 s.46
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• pp.251-258
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• 2000

Based on the numerical investigations using steel bridge pier subjected to strong seismic excitations a new approach to seismic damage assessment for steel structures and their members has been proposed in conjunction with the suggested definition of failure state. The relevant failure form of the steel pier is evaluated. It is revealed that when a seismic load has a short period, the failure of global buckling beyond the allowable displacement is more dominant than that by that of the local buckling caused by the accumulation of plastic strain. When a seismic load is not beyond this certain part, but repeats within the range of where a plastic deformation occurs, the plastic strain is accumulated on the partial element of bottom edge of steel pier and the failure occurs by the local buckling from the accumulated plastic local strain.

• Journal of Soil and Groundwater Environment
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• v.20 no.5
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• pp.34-40
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• 2015

It is reported that the intensity of rainfall will likely increase, on average, over the world on 2000. For water resources security, many studies for flow paths from rainfall or snowmelt to subsurface have been conducted. In Korea, few isotopic studies for characterizations of flow path have been undertaken. For a better understanding of how water derived from atmosphere moves to subsurface and from subsurface to stream, an analysis of precipitation and stream water using oxygen-18 and deuterium isotopes in a small watershed, Dorim-cheon, Seoul, was conducted with high resolution data. Variations of oxygen-18 in precipitation greater than 10‰ (δ¹⁸O_max = −1.21‰, δ¹⁸O_min = −11.23) were observed. Isotopic compositions of old water (groundwater) assumed as the stream water collected in advance were −8.98‰ and −61.85‰ for oxygen and hydrogen, respectively. Using a two-component mixing model, hydrograph separation of the stream water in Dorim-cheon was conducted based on weighted mean value of δ¹⁸O. As a result, except of instant dominance of rainfall, contribution of old water was dominant during the study period. On average, 71.3% of the old water and 28.7% of rainfall contributed to the stream water. The results show that even in the small watershed, which is covered with thin soil layer in granite mountain region, the stream water is considerably influenced by old water inflow rather than rainfall.

• Journal of Environmental Impact Assessment
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• v.18 no.3
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• pp.151-160
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• 2009

In order to use fundamental data for conservation of species diversity and stream health with dam development, fish investigation in up- and downstream of Pyeonglim Dam was seasonally conducted in 2007~2008. In addition, data of water qualities, investigated for environmental impact assessment, were used to determine a water quality standard level in Pyeonglim Stream, and it revealed that water environment condition was good in the stream. During the study period, a total number of fish caught from the 4 study sites was 5,449 representing 9 families 25 species, and there were 8 Korean endemic species (32.0%) including Rhodeus uyekii, Squalidus gracilis majimae, and Microphysogobio yaluensis. Two species of Zacco temminckii (37.5%) and Zacco platypus (26.3%) were dominant and subdominant in all sites. There were few individuals of the $2^{nd}$-class endangered species (Sand lamprey, Lampetra reissneri) and the introduced species (Bluegill, Lepomis macrochirus), found in the upstream of the dam. and further investigation for conservation of the endangered species and for prevention of the introduced species is needed in future. With fish fauna and multi-metric health assessment model in each sampling attempt, index of biotic integrity(IBI) was evaluated and it resulted mostly in good(26~35) and excellent(36~40) condition in all sites. The results indicate that it is very important to study not only environmental impact assessment with fish composition but also stream health assessment in order to conserve healthy aquatic ecosystem.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.2
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• pp.1-12
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• 2017

This study aims to provide the basic habitat data for the alternative breeding sites of Family Ardeidae including Ardea cinerea, Egretta alba modesta, Egretta intermedia, Egretta garzetta, Bubulcus ibis and Nycticorax nyciticorax. Species numbers, flight directions for detecting foraging grounds and current vegetation structure were investigated nesting at Gunsan urban forest area. Data were collected over a period of 10 weeks, from 15 June - 31 August 2014. The total nest and population of Family Ardeida were 684 and 1,712 respectively. Percentage of birds observed flying in 8 major compass directions were as follows. 57.27% of all birds were observed flying northwest, 22.09% were observed flying south and 13.40% were flying north. For possible foraging areas, to the northwest, there are Geumgang river tidal flats, and to the south, paddy fields and streams within 2km. Flying directions by species (${\chi}^2=287.18$, P<.001, Cramer's V=0.12) and by seasons(${\chi}^2=839.94$, P<.001, Cramer's V=0.19) showed significant difference statistically. In relation between species and directions, 60.31% and 24.05% of Bubulcus ibis and 59.40% and 23.00% of Ardea cinerea were observed flying northwest and south respectively. Vegetation in the sites consist of an overstory of 3 to 7 species. At site 1, Pinus thunbergii was the dominant species and site 2, Chamaecyparis obtusa. Understory vegetation is composed of shrubs, saplings and small trees of Chamaecyparis obtusa, Quercus acutissima, Smilax china and Platycarya strobilacea. Egrets and herons usually nested at the dense population and canopy overlayed forest, and especially branches and leaves of smallwood with less than 10cm of breast height diameter were relatively severely damaged due to the nesting and excreta.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.21-29
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• 2010

The phenolic compounds are a major contaminant class often found in industrial wastewaters and the biological treatment is an alternative tool commonly employed for their removal. In this sense, monitoring microbial community dynamics is crucial for a successful wastewater treatment. This work aimed to monitor the structure and activity of the bacterial community during the operation of a laboratory-scale continuous submerged membrane bioreactor (SMBR), using PCR and RT-PCR followed by denaturing gradient gel electrophoresis (DGGE) and 16S rRNA libraries. Multivariate analyses carried out using DGGE profiles showed significant changes in the total and metabolically active dominant community members during the 4-week treatment period, explained mainly by phenol and ammonium input. Gene libraries were assembled using 16S rDNA and 16S rRNA PCR products from the fourth week of treatment. Sequencing and phylogenetic analyses of clones from the 16S rDNA library revealed a high diversity of taxa for the total bacterial community, with predominance of Thauera genus (ca. 50%). On the other hand, a lower diversity was found for metabolically active bacteria, which were mostly represented by members of Betaproteobacteria (Thauera and Comamonas), suggesting that these groups have a relevant role in the phenol degradation during the final phase of the SMBR operation.