• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.151-164
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• 2006

We monitored the current macrozoobenthic community structure after the Sea Prince oil spill around Keumo-do and Sori-do, Korea. Macrobenthic animals were collected seasonally around Sori-Keumo do using a van Veen grab ($0.1m^2$) from October 1999 to April 2000. In total, 196 species were identified at 46 sites around Keumho-do. The mean density was 1,460 individuals/$m^2$, and polychaetes comprised 80% of the total density of the macrozoobenthic. Dominant species were the polychaete Tharyx sp. (51%), the echinoderm Amphioplus megapomus (5%) and the polychaete Lumbrineris longifolia (3%). We identified 176 macrobenthic species at 36 sites around Sori-do. The mean density was 1,068 individuals/$m^2$, and polychaetes was the most abundant faunal group, comprising 41%, followed by mollusks (24%) and echinoderms (20%). Dominant species in Sori-do were the mollusk Potamocorbula amurensis (23%), the chinoderm Amphioplus megapomus (14%), and the polychaete Tharyx sp. (10%). The overall community structures in the study area showed few seasonal changes, although there was a gradual change in the species composition within each benthic community. Tharyx sp. was the most abundant species in the study area. Because this species has not been found in the other coastal areas except during recent investigations, it is considered to have increased during the course of community succession after the oil spill. The macrozoobenthic around Keumo-do showed little change in species richness, whereas around Sori-do, it showed a few increases in species richness after the summer of 1998. The overall density showed the same trend as species richness. Based on improved community indices, we suggest that the macrozoobenthic communities around Sori-Keumo Islands are gradually recovering from the oil-spill damagecaused by the oil spill.

• 한국해양학회지
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• v.30 no.4
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• pp.271-278
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• 1995

A study of heavy mineral sands in terms of heavy mineral group and concentration has been carried out by analyzing 88 grab samples from the continental shelf off the southeast coast of Korea. Heavy mineral groups seem to be outlined and classified into four regions in the study area: 1) the western region; high concentrations of stable minerals, such as opaque mineral, magnetite, garnet and ZTR, 2) Korean Trough region; moderate concentrations of stable minerals, 3) the eastern region; abundant altered mineral and amphibole with minor of pyroxene concentration, and 4) the northeastern shelf-break region; low concentration of stable minerals with abundant altered minerals. The sedimentologic natures of four major heavy mineral regions (groupings) seem to be influenced by physical, dynamic and hydraulic milieu and also aerial and/or subaqueous weathering processes. It seems to be, further, plausible that shallow marine waves and currents associated with neritic dynamic condition of transgressive sea might be very effective on the concentration and groupings (sorting) of heavy min-erals in the surficial sediments of the continental shelf. The pyroxene-abundant heavy mineral suite (group), in fact, seems to suggest a sediment source from Japanese Islands.

• Applied Biological Chemistry
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• v.41 no.2
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• pp.197-200
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• 1998

The MeOH extracts obtained from the flower petals of Carthamus tinctorius were solvent-fractionated with EtOAc, n-BuOH, and $H_2O$, successively. From the n-BuOH extract 2 flavonoid compounds were isolated through the repeated silica gel column chromatographies. From not only the results of physico-chemical data including HMBC but also the adaptation of acid hydrolysis, the chemical structures of the compounds were determined as $3-O-[{\beta}-D-glucopyranosyl(1{\rightarrow}2)\;{\beta}-D-glucopyranosyl]\;kaempferol$ and $3-O-[{\alpha}-L-rhamnopyranosyl(1{\rightarrow}6)\;{\beta}-D-glucopyranosyl]\;kaempferol$. The compounds exhibited $IC_{50}$ values in Grab2-Shc activity to be 43 and $47{\mu}g/ml$, respectively.

• Journal of Families and Better Life
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• v.22 no.6 s.72
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• pp.133-142
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• 2004

The purpose of this study was to investigate the spatial composition characteristics of elderly housing facilities in Korea, in order to refer them in establishing the basic plan for elderly housing in Korea. The case study performed in this study from October 16 to October 31 is based on ten housing facilities for the elderly in KOREA. During the site visits, the interview with the custodians, survey of the space, picture taking and diagram gathering were carried out. The results of this study were as follows; 1. The type of floor plan was classified into ㅁ type, L type, and ㅡ type. And they hadn't an outside space called a garden(courtyard). 2. The kinds of common spaces could be grouped as the space for basic living, for leisure, and for convenient living. Also it was all common that the housing facility had common diningroom laundry room once, and activity room. The type of the common spaces was categorized into three types, the centralized type where the shared space was located at the center of the housing facilities, the distributed type, depending on the degree of separation between common spaces and units, and another each building type. 3. The kinds of units was classified into studio, oneroom, one bedroom and two bedroom. 4. Elevator, safety grab bar, emergency bell, and the door handle of lever or bar type were placed in these facilities.

• Journal of Species Research
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• v.2 no.2
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• pp.159-166
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• 2013

Typical of large, oligotrophic lakes, Lake H$\ddot{o}$vsg$\ddot{o}$l, Mongolia, exhibits complex morphometry which should support a spatially heterogeneous community of benthic macroinvertrates. The lake also exhibits a broad range of land uses. Based on the variation in land use and complex physical habitat of the lake (e.g. substrate variation and presence of affluent streams in bays), we asked two questions. First, does density of total benthic macroinvertebrates vary between different bays in Lake H$\ddot{o}$vsg$\ddot{o}$l? Second, does density of individual benthic taxa vary by bay? Samples collected in 1997, the last year for benthic sampling of the lake, were designed to test for variation in macroinvertebrate density between bays and can now be used to establish baseline variation in density for future studies. A total of 56 Ponar grab samples were analyzed from six bays in Lake H$\ddot{o}$vsg$\ddot{o}$l. Results of a general linear model analysis of variance showed that total density of macroinvertebrates varied only slightly between bays of the lake, but that most individual taxa showed significant variation between bays. Variation in density for most taxa was linked to substrate composition rather than other geographic or physical variables in the lake. Recent increases in grazing intensity and ecotourism along the shores should be managed to reduce the nutrient load into the lake to avoid impairment of the benthic biota of this unique, ancient ecosystem.

• Ocean and Polar Research
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• v.29 no.4
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• pp.339-348
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• 2007

In this work, we compared the characteristics of three benthic biotic indices (BPI, AMBI, BIBI) which indicates the health condition of benthic communities in Masan Bay, Korea where anthropogenic impacts have been concentrated. Also we evaluated the usefulness of these benthic indices and some problems if they were applied to the Korean coastal waters. For this we used the macrozoobenthos data collected using van Veen grab ($0.1\;m^2$) at 21 sites in Masan Bay in February and August 2004. Based on the BPI values, two stations in the inner bay were found in a very hard polluted condition and three stations in the middle bay were also in a highly polluted condition. Only one station located in the bay mouth was in a normal condition. The inner bay stations showed very high AMBI values (${\geq}5.0$), indicating a highly polluted condition. The bay mouth station was assessed in a moderately polluted condition. The overall BIBI values in Masan Bay were in the range between 1.0 and 3.0. The inner bay stations showed low BIBI values (${\leq}2.0$) in the severely degraded condition. The bay mouth station with high BIBI value over 3.0 was assessed as a normal condition. All three benthos indices showed that macrozoobenthic communities in the inner bay were in a seriously polluted condition all year round, and macrobenthic faunas in the bay mouth seemed in a bad healthy condition (slightly polluted) based on AMBI during summer season. These three benthic biotic indices showed the similar assessment result, and thus we consider that each of them is a useful tool for the assessment of coastal benthic ecosystems under the organic enrichment in sediment.

• Journal of Digital Convergence
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• v.16 no.10
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• pp.545-555
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• 2018

The current study uses photovoice, a participatory and quantitative method of research, to understand the stress in the youth through the experiences of university students. The study was conducted in the order of education, data collection, data analysis for six session college students in J city. The results was largely categorized into three themes as follows. Firstly, as sub-themes of meaning of stress, there were 'Spider web that clogs the head', 'Seemingly endless passage', 'Anxiety that keeps hands fidgeting', Secondly, factors of stress, there were 'Life does not depend on the class rank', Financial hardships,' Frustrated with getting a job', 'Difficulty in time management', Thirdly, how to cope with stress, there were 'A friend you can freely talk to and laugh with', 'Grab some food and release some stress', 'Get away from daily life', Positive thinking relaxes body and spirit'. Based 0n the analyzed results, we can understand the causes and coping strategies of college students in depth, suggested the practical suggestions and limitation of college society about stress and the educational implication of utilizing photovoice.

• The Journal of the Acoustical Society of Korea
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• v.26 no.2E
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• pp.44-49
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• 2007

Donghae City - Ulleung Island Line (DC-UI Line) is a representative line for underwater and geoacoustic modeling in the middle western East Sea. In this line, an integrated model of P-wave velocity is proposed for a low-frequency range target (<200 Hz), based on high-resolution seismic profiles (2 - 7 kHz sonar and air-gun), shallow and deep cores (grab, piston, and Portable Remote Operated Drilling), and outcrop geology (Tertiary rocks and the basement on land). The basement comprises 3 geoacoustic layers of P-wave velocity ranging from 3750 to 5550 m/s. The overlying sediments consist of 7 layers of P-wave velocities ranging from 1500 to 1900 m/s. The bottom model shows that the structure is very irregular and the velocity is also variable with both vertical and lateral extension. In this area, seabed and underwater acousticians should consider that low-frequency acoustic modeling is very range-dependent and a detailed geoacoustic model is necessary for better modeling of acoustic propagation such as long-range surveillance of submarines and monitoring of currents.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1729-1733
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• 2010

본 연구에서는 7개 지점(여주, 적성, 왜관, 진동, 공주, 구례2, 나주)에 대해 유사량 특성 분석을 수행하였다. 부유사량은 강우가 집중되는 홍수기와 이의 전 후시기인 저 평수기(2회)로 나누어 왕복수심적분법(D-74)으로 측정하였고, 하상토는 BM-54, Grab Sampler(60 L), 선격자 등을 이용하여 홍수기 전 후로 2회 채취하였다. 채취된 시료는 그 목적에 따라 여과법(부유사농도), BW관법(부유사입도분포), 체분석법(하상토입도분포)으로 분석하였고, 그 결과로 작성된 평균 부유사농도 및 Oden Curve와 입도분포곡선과 수리량(수위, 유속, 측정수심, 수면폭, 수면경사, 수온)등의 자료를 이용하여 총유사량(미측정구간의 유사량 포함)을 추정(실측+계산: Modified Einstein)하였다. 총유사량 추정시, 세류사량을 제외한 부유사량을 적용하였다. 유량-부유사농도와 부유사량 및 총유사량 관계에 대한 결과는 다음과 같다: 1) 하나의 강우사상의 수위 상승-첨두-하강에 대한 측정성과는 대체적으로 Loop 형태를 보였고 이로 인해 일부 지점에서 측정성과들 간의 산포도가 다소 크게 나타났으며 수위 하강 때보다 상승시 초기 탁도의 증가 현상으로 부유사농도가 더 높은 것을 볼 수 있었다. 2) 유량-부유사농도, 부유사량, 총유사량 관계에서 왜관과 공주 지점의 경우, 첨두 수위에서 값들의 최고치를 보였고 나머지 지점들은 첨두 수위의 앞선 측정 수위에서 최고치를 보였다. 이는 강우사상별, 강우강도, 댐 방류량, 수위 상승-하강부, 유량에 따른 부유사농도와 부유사량의 특성이 각각 다른 점과 총유사량 추정시, 추정방법에서 추천하는 범위에서 벗어나는 자료를 적용해서 나타나는 결과로 판단된다. 여기서 유량, 수심, 하상토의 입도크기 등 자료의 범위가 추정공식들이 추천하는 범위에서 벗어나면 그 분석 결과도 서로 다르게 나타난다는 것은 그만큼 총유사량 공식의 범용성이 적다는 것을 의미한다. 이러한 점에서 때로는 자료 전체에 대해 전반적으로 양호한 결과를 보이는 공식보다는 정확한 답을 원하는 자료의 범위 내에서 예측하는 공식을 선정하는 것이 필요하다. 즉, 공식을 적용하여 유사량을 추정하고자 하는 하천이나 수로의 특성에 맞는 유사량 공식을 선정하는 것이 중요하다는 것이다.

• Journal of Ocean Engineering and Technology
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• v.31 no.4
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• pp.308-314
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• 2017

The purpose of this study was to investigate the sea floor using a seismic profiler in the northern part of Chagwi-do of Jeju Island in order to select the optimal location for the 60-m-class berth of a sea test bed for wave energy converters and provide basic environmental data for designing a suction anchor. The echo types of the seismic profiles were classified based on the study of Kim et al. (2016a), and the location for installing the suction anchor was selected based on a sediment thickness of more than 10 m. The physical properties of the surface sediments were determined by analyzing the sediment samples obtained from 16 grab sample points. Based on the investigation and analysis, we proposed a survey area in the North-Eastern sea as an optimum location for the 60-m-class berth where the suction anchor could be installed.