• Ocean Science Journal
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• v.40 no.3
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• pp.127-143
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• 2005

The taxonomic sufficiency approach has been proposed as a surrogate for the typical analysis of species-abundance data, especially in conditions involving prominent pollution gradients. Here, we evaluate the use of taxonomic sufficiency with infralittoral macrobenthic data derived from samples taken in a moderate polluted subtropical environment in southeastern Brazil, analysing five taxonomic levels and including two functional levels throughout polychaete feeding guilds and trophic groups. The data were collected seasonally at nine stations and studied for two abundance data series (0.5 and 1.0 mm sieve mesh-size). The results showed a similar ordination pattern between the two sieve mesh-size, but with the 0.5 mm sieve data a different pattern was observed during austral summer. A slight loss of information was detected using genus, family, polychaete species and their feeding guilds as taxonomic/functional units. These results together with those of the cost! benefit ratio, suggested that the family level seemed to be sufficient to detect the impact caused by moderate pollution in this shallow-water, subtropical environment. In additional, through the use of feeding guilds, similar patterns are obtained. Correlation analysis showed that chlorophyll a, total organic matter, zinc, and chromium sediment content were the variables that best explained the biological pattern observed and not always the best correlation coefficient occurring at the species level. The feeding guild approach seems to be useful and generates interpretable results similar to those obtained with the species level of the whole macroinfauna. The results showed an important cost reduction in the sample processing, suggesting that it is possible to adopt a coarser taxonomic level monitoring program even in species-rich communities.

• Journal of information and communication convergence engineering
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• v.9 no.4
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• pp.475-482
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• 2011

In this research, we have attempted to estimate the water quality of fish farms in terms of parameters such as water temperature, dissolved oxygen, pH, and salinity by employing observational data obtained from a coastal ocean observatory of a national institution located close to the fish farm. We requested and received marine data comprising nine factors including water temperature from Korea Hydrographic and Oceanographic Administration. For verifying our results, we also established an experimental fish farm in which we directly placed the sensor module of an optical mode, YSI-6920V2, used for self-cleaning inside fish tanks and used the data measured and recorded by a environment monitoring system that was communicating serially with the sensor module. We investigated the differences in water temperature and salinity among three areas - Goheung Balpo, Yeosu Odongdo, and the experimental fish farm, Keumho. Water temperature did not exhibit significant differences but there was a difference in salinity (significance <5%). Further, multiple regression analysis was performed to estimate the water quality of the fish farm at Keumho based on the data of Goheung Balpo. The water temperature and dissolved-oxygen estimations had multiple regression linear relationships with coefficients of determination of 98% and 89%, respectively. However, in the case of the pH and salinity estimated using the oceanic environment with nine factors, the adjusted coefficient of determination was very low at less than 10%, and it was therefore difficult to predict the values. We plotted the predicted and measured values by employing the estimated regression equation and found them to fit very well; the values were close to the regression line. We have demonstrated that if statistical model equations that fit well are used, the expense of fish-farm sensor and system installations, maintenances, and repairs, which is a major issue with existing environmental information monitoring systems of marine farming areas, can be reduced, thereby making it easier for fish farmers to monitor aquaculture and mariculture environments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.5
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• pp.1390-1411
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• 2024

Underwater Wireless Sensors Networks (UWSNs) are deployed in remotely monitored environment such as water level monitoring, ocean current identification, oil detection, habitat monitoring and numerous military applications. Providing scalable and efficient routing is very challenging in UWSNs due to the harsh underwater environment. The biggest difficulties are the nodes inherent movement due to water current, long delay in data transmission, low bandwidth of the acoustic signal, high error rate and energy scarcity in battery powered nodes. Many routing protocols have been proposed to solve the aforementioned problems. There are three broad categories of routing protocols namely depth based, energy based and vector-based routing. Vector Based Forwarding protocols perform routing through virtual pipeline by defining their radius which give proper direction to packets communication. We proposed a routing protocol termed as Path-Oriented Energy Scaled Expanded Vector Based Forwarding (PESEVBF). PESEVBF takes into account all parameters; holding time, the source nodes packets routing path and void holes creation on the second hop; PESEVBF not only considers the packet upward advancement but also focus on density of the forwarded nodes in terms of number of potential forwarding and suppressed nodes for path selection. Node selection in resultant holding time is based on minimum Path Factor (PF) value. Moreover, the suppressed node will be selected for packet forwarding to avoid the void holes occurrences on the second hop. Performance of PESEVBF is compared with other routing protocols using matrices such as energy consumption, packet delivery ratio, packets dropping ratio and duplicate packets creation indicating considerable performance improvement.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.4
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• pp.253-264
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• 2002

Surface ozone concentrations measured at 40 monitoring sites in three major cities (Seoul, Busan, and Daegu) of Korea during 1993~2000 were analyzed to understand the characteristics of temporal and spatial distributions. Trends were analyzed for annual mean, 95th percentiles of daily 8-hour maximum and days exceeding 8-h ozone standard of 60 ppb. Three indicators exhibited increasing trends (+0.75 ppb yr$^{-1}$ , +2.20 ppb yr$_{-1}$ , and +5.35 days yr$_{-1}$ on average) throughout the study period at all cities. Diurnal and seasonal variations were the largest in Seoul followed by Daegue and Busan, due to the high photochemical production and titration of ozone (Seoul), strong wind and constant supply of background ozone from the ocean (Busan). In the urban centers and industrial areas at all cities, scavenging of ozone by NO reduces the daily 8-hour maximum ozone by 10 ppb on average. High concentrations of ozone have frequently occurred in downwind eastern (Seoul and Daegu) or northern (Busan) sides of the territory. In particular, the coastal area of Busan had relatively high ozone level due to the local sea land breeze circulation. The results indicated that the temporal and spatial variations of ozone concentration were non -uniform and were closely related to the local environments; emission levels, climates, and geographic locations.

• Journal of Environmental Science International
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• v.28 no.2
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• pp.191-201
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• 2019

This study suggested a vegetation restoration plan for a coastal area where the ecosystem conservation fund return project, targeting the whole area of Dalmaji-gil, located in Haeundae, Busan. After distinguishing if it would be a proper site for the operation of the ecosystem conservation fund return project by analyzing the ecological environment, human environment, and the current status of land owners, the target species for vegetation restoration was determined, and the facilities and programs were selected in accordance with the spatial division of the biosphere reserve. The basic direction is as follows. First, is the expansion of green space and the securement of life habitats downtown. Second, is the conservation of core areas by separating the conserved area from the space for use. Third, is the establishment of ecological resting space and the reinforcement of an ecological educational programs. The significance of this study is to suggest a vegetation restoration plan of a coastal area, fully utilizing the existing vegetation of the subject area, by suggesting the land use and flow planning, environmental improvement (vegetation restoration) plan, life habitats establishment plan, planting plan, and hydrologic plan, facilities, maintenance, and monitoring plan based on the basic direction. This study would provide useful basic data for ecosystem conservation and restoration in the Korean Peninsula, surrounded by the ocean on three sides.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.3
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• pp.278-286
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• 2019

The Port of Pyeong Taek is located on the west coast, meaning that the difference between the rise and fall of tide is great (flood tide 1.8 to 2.9 knots, ebb tide 1.6 to 2.9 knots). Due to mainly N~NW'ly strong winds & high waves during winter, navigating as well as loading & discharging vessels must focus on cargo handling. The strong tidal and wind forces in the Port of Pyeong Taek can push an LNG carrier away from its berth, which will end up causing forced disconnection between the vessel's cargo line and shore-side loading arm. The primary consequence of this disconnection will be LNG leakage, which will lead to tremendous physical damage to the hull and shore-side equipment. In this study, the 125K LNG Moss Type ship docked at No. 1 Pier of the Pyeong Taek is observed, and the tension of the mooring line during cargo handling is calculated using a combination of wind and waves to determine effective mooring line and mooring line priority management. As a result if the wind direction is $90^{\circ}$ to the left and right of the bow, it was found that line monitoring should be performed bearing special attention to the Fore Spring Line, Fore Breast Line, and Aft Spring Line.

• Mycobiology
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• v.49 no.6
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• pp.551-558
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• 2021

The Federated States of Micronesia (FSM) is an island country in the western Pacific and is a known biodiversity hotspot. However, a relatively small number of fungi (236 species) have been reported till July 2021. Since fungi play major ecological roles in ecosystems, we investigated the fungal diversity of FSM from various sources over 2016 and 2017 and constructed a local fungal inventory, which also included the previously reported species. Fruiting bodies were collected from various host trees and fungal strains were isolated from marine and terrestrial environments. A total of 99 species, of which 78 were newly reported in the FSM, were identified at the species level using a combination of molecular and morphological approaches. Many fungal species were specific to the environment, host, or source. Upon construction of the fungal inventory, 314 species were confirmed to reside in the FSM. This inventory will serve as an important basis for monitoring fungal diversity and identifying novel biological resources in FSM.

• Journal of Marine Life Science
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• v.8 no.1
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• pp.68-77
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• 2023

In this study, we investigated the quantitative distribution of microplastics in the surface seawater at 8 points near the Taean Peninsula using fluorescence staining. The study revealed a detection range of microplastics from 0 to 360.5 particles/l, with an average of 149.7 ± 46.0 particles/l. When classifying the microplastics by size, it was found that particles smaller than 50 ㎛ were dominant, although there were differences at Site 3. Moreover, it was not possible to identify clear correlations when comparing the number of microplastics based on collection area and particle size. Various physical and chemical factors, including plastic material, dynamic ocean conditions (such as currents, wind, waves, tides), geological characteristics (topography, slope), sediment materials including coastal organisms, human activities (fishing, development, tourism), and weather conditions (floods, rainfall), affect the behavior of microplastics. Therefore, future efforts should focus on standardizing quantitative analysis methods and conducting fundamental research on microplastic monitoring, including the analysis of environmental factors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.372-378
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• 2016

A mound was constructed to install a caisson and sofa blocks underwater. The mound riprap, which were of uniform grade, size, shape, and specific gravity, formed the foundation for the support superstructure. Also, rubble leveling works were performed before installing structures such as caissons. In this study, underwater construction equipment was developed with a remotely controlled operating system and underwater environment monitoring system for unmanned underwater rubble leveling work. The performance of the developed equipment was verified using on-land and underwater tests. In addition to the performance verification, the construction process and economic efficiency of the equipment should be checked before applying it to the real construction field for commercial purposes. In this paper, a construction process using the developed equipment was proposed and compared with the existing rubble leveling method. The results demonstrated that the new construction method has higher economic efficiency and safety than the existing construction method.

• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.1-4
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• 2008

근년 일본, 캐나다, 호주, 미국, EU(주로 노르웨이, 영국) 등에서 인공위성을 이용한 해양 안전의 확보를 위한 연구개발이 진행되고 있으며, 일부 실해역 적용의 분야도 도출되고 있는 실정이다. 9.11테러 이후, 국제해사기구에서도 해상보안의 문제는 주요 이슈로 대두되어, 해상보안에의 활용 기술 개발이 먼저 시작되었다. 그 외, 밀입국 선박 감시 덴 해양오염 모니터링이 주요 활용분야이다. 간단하게 요약하면 다음과 같다. -노르웨이: Norwegian Defence Hesearch Establishment(NDRE)에서 주도적으로 선박 탐지 실험 및 기술 개발을 실시. 주로, ESA의 위성을 활용. 국가 보안의 목적으로는 적용을 하고 있음. -캐나다: 캐나다에서 소유하고 있는 RADARSAT을 이용하여 가장 많은 실험을 실시함. 영상을 처리하고 결과에 대한 평가를 수행하기 위한 시스템(Ocean Monitoring Workstation, OSM)을 개발하여 보급에 주력. -호주: 주로 캐나다의 위성 및 시스템의 적용을 하고 있음 영해 및 환경 감시의 역할을 수행. Coastwatch조직을 만들어 해상 감시활동을 하고 있음. -영국: 데이터 취득 후, 2.5시간 이내에 선박의 위치를 전송하는 인터페이스를 개발함. 일본의 경우, 다른 선진국에 비해서는 다소 늦게 시작되었다. 2003년 발간된 '재해 등에 대응한 인공위성이용기술에 관한 종합보고서'를 시작으로 정보수집위성 4기 및 지구관측위성을 이용한 해양 감시 활동이 시작되었다. 또한, 제 3기 과학기술기본계획(2006-2012)내에 해양 불법침입 탐지 기술 개발 항목이 반영되어 있다. 유럽의 해상보안서비스(MARISS)의 사용자 워크숍이 ESA ESRIN(이탈리아 프라스카티)에서 2008년 1월 22일 열렸다. 실질적인 내용은, '해상보안을 위한 우주 시스템'에 관한 것으로 인공위성 이용하는데 있어 설계안 및 데이터 이용 컨셉을 제시하는 것이었다. 여기서 중요한 것은 국가간의 협력이 절대적으로 필요하며, 기존의 시스템과의 통합에 있어 신뢰성을 어떻게 확보하는가에 있다고 할 수 있다. 또한, 보안과 환경모니터링의 기능이 분리되어 진행되고 있는 부분에 대한 정보 통합 방향도 제기되었다. 국내에서도 AIS와 SAR정보의 결합에 관한 검토는 이루어졌으며, 이를 바탕으로 EU와 같은 시스템의 구축(조직과 연구개발)을 위한 실질적인 검토가 필요하다.