• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.300-301
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• 2003

갈치 (Trichiurus lepturus Linnaeus)는 우리나라 서해 및 남해, 동중국해, 발해, 일본 서부 및 류슈 연안 등 한국 주변 수역에 넓게 분포하는 난류성 저어어종이다. 우리나라 갈치의 주어장은 EEZ 설정 후 어장이 많이 축소되어 최근에는 흑산도, 제주도 인근의 서해남부 및 제주도 서방해역에서 근해안강망, 쌍끌이기선저인망, 대형트롤, 대형선망, 근해채낚기 등에 주로 어획된다. 우리나라 갈치의 어획량은 1970년대 초반에는 급격한 증가추세로 1974년에 17만톤으로 가장 많았으며, 이후 1977년에 7만톤 수준으로 떨어졌고, 1997년부터 다시 높은 수준으로 회복 되면서 1983년에 다시 15만톤의 어획을 기록하였다. (중략)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2020.11a
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• pp.28-30
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• 2020

우리나라 해역은 크게 동해, 서해와 남해로 나뉜다. 해역별 특성은 공간적 및 유체역학적으로 상이하여 해역별 수중거주시설의 설계에 있어 서로 다른 주요건과 시설구성을 필요로 한다. 본 연구는 거시적 수중주거시설 설계기술 연구의 일환으로서 특히 해역별 공간 특성을 잘 갖춘 3곳의 입지 후보지(동해:Phoenix point, 남해:South Brother point와 서해:Mud point)에 대하여 요구되는 해역별 설계 환경부하를 최근 태풍Haishen, 태풍Maysak과 태풍 Bavi의 기상 예측자료 및 관측자료를 통해 비교하고 가정한 건축목표(Phoenix point: 속초시에 탈탄소 전력공급, South Brother point:부산항 수소연료 비축기지 및 해상 수소충전소, Mud point:에너지 자립형 기후중립 수산양식 기지)에 부합하도록 시설구성을 제안함으로써 우리나라 연안의 천해와 심해에서의 수중거주 가능성을 조사했다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.7
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• pp.777-786
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• 2020

This study examines the efficiency of safety management measures taken in coastal waters to prevent coastal accidents. Recent years have witnessed about 800 cases of large and small coastal accidents in coastal waters annually. On average, these accidents have been responsible for 129 deaths annually, Thus, there is a need for effective preventive measures. Accordingly, the Korea Coast Guard enacted the Coastal Accident Prevention Act in 2014 and has cooperated with related organizations, such as local governments and the Ministry of Oceans and Fisheries, to safely manage coastal waters. However, compared to the rapid increase in human coastal activities, coastal accidents continue to occur due to the lack of a safety mindset among the Korea Coast Guard, a lack of public safety awareness, a lack of safety management facilities, and poor interest from related organizations, among others. This study examines the conditions and problems faced with regard to safety management in coastal waters based on recent coastal accident data, and analyzes foreign coastal waters safety management cases. Various methods to improve the safety management efficiency in coastal waters are proposed, such as enhancing the safety mindset and capabilities of the Korea Coast Guard, strengthening cooperation among related organizations, increasing the role of local governments, expanding and strengthening safety management facilities by applying new technologies, inculcating a culture of maritime safety, and activating private-public collaborative governance.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.536-542
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• 1984

Fish eggs and larvae in the western waters of Korea are surveyed during the periods from February to August in 1982. Six species of eggs and forty-two species of larvae are occurred in the survey area. The dominant species occurred during the study periods are Ammodytes personatus, Enedrias sp., Engraulis japonica, Callionymus sp., Gobiidae, etc. Major spawning month and ground of each species are estimated from the data, i.e., occurrence month and abundance of eggs and larvae by survey month and area, as well as the optimum water temperature and salinity for spawning.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.14-22
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• 2017

The frequency and scale of natural disasters due to the abnormal climate phenomena caused by global warming have being increasing all over the world. Various natural disasters, such as typhoons, earthquakes, floods, heavy rain, drought, sweltering heat, wind waves, tsunamis and so on, can cause damage to human life. Especially, the damage caused by natural disasters such as the Earthquake of Japan, hurricane Katrina in the United States, typhoon Maemi and so on, have been enormous. At this stage, it is difficult to estimate the scale of damage due to (future) natural disasters and cope with them. However, if we could predict the scale of damage at the disaster response level, the damage could be reduced by responding to them promptly. In the present study, therefore, among the many types of natural disaster, we developed a function to estimate the damage due to wind waves caused by sea winds and waves. We collected the damage records from the Disaster Report ('91~'14) published by the Ministry of Public Safety and Security about wind waves and typhoons in the western coastal zone and, in order to reflect the inflation rate, we converted the amount of damage each year into the equivalent amount in 2014. Finally, the meteorological data, such as the wave height, wind speed, tide level, wave direction, wave period and so on, were collected from the KMA (Korea Meteorological Administration) and KHOA (Korea Hydrographic and Oceanographic Agency)'s web sites, for the periods when wind wave and typhoon damage occurred. After that, the function used to estimate the wind wave damage was developed by reflecting the regional characteristics for the 9 areas of the western coastal zone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.83-91
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• 1984

The formation and structure of tidal front in the eastern part of the Yellow Sea were studied based on the oceanographic data compiled during the periods of $1982{\sim}1983$ and $1966{\sim}1970$. Well-defined fronts occurring in the Yellow Sea in summer mark the boundary between the stratified and vertically mixed regimes. The occurrence of vertically mixed regimes may be interpreted in terms of available turbulent kinematic energy of tidal currents. The tidal frontal regions were determined by horizontal gradients of temperature, salinity and dissolved oxygen, and were verified by water colour and transparency. In summer the tidal fronts were found at depths of $15{\sim}25m$ at about 20 miles from the shore. Potential energy of vortical stratification in the tidal frontal region was 10 $Joule/m^3$. The stratification parameter in the frontal region computed from the numerical tidal model was $S_p=1.0.$ Tidal front is formed in regions with $S_p=1-1.5,$ if surface heat flux are constant. Waters in the stratified region have the layer structures of wind-mixed surface layer, thermocline and tidal-mixed bottom layer. In the vertically mixed region, however, sea water is nearly homogeneous. in winter no distinctive tidal front was seen.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.529-534
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• 1994

The lethal concentration(LC50) of several micropollutants for three species of the fish Paralichthys olivaceus, Mugil cephalus and Sebastes schlegeli were determined by acute toxicity tests. For the determination of definitive test concentrations, the fish were exposed to three test material concentrations spaced at order-of-magnitude intervals based on a logarithmic ratio in range finding tests. LC50 was determined by five concentrations of test material in a geometric progression by means of range finding tests. The 96hr-LC50 values(mg/l) were estimated by the graphical interpolation of probability-logarithm transformations. These indicated that the order of sensitivities to three kind of micropollutants was Mugil cephalus > Paralichthys olivaceus > Sebastes schlegeli.

• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.19-36
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• 2013

Physiochemical characters of sea waters during summer flood- and winter dry-seasons and their spatial variations were investigated along the coastal area off the eastern South Sea, Korea. Using the hierarchical clustering method, in this study, we present comprehensive analyses of coastal waters masses and their seasonal variations. The results revealed that the coastal water of the study area was classified into six water masses (A to F). During summer season, the surface water was mainly occupied by the coastal pseudo-estuarine water (water mass B) with low salinity and high nutrients and the river-dominated coastal water (water mass C) with low nutrients, respectively. The bottom water was dominated by cold water (water mass D) with very low temperature, high salinity and high nutrients, compared to masses of surface water. Notably, the water mass B, with high concentrations of nutrients (silicate and nitrogen) and low salinity, which is strongly controlled by the water quality of river freshwater, seems to play an important role in controlling the water quality and further regulating physical processes on ecosystem in the eastern coastal area of South Sea. The water mass D (bottom cold water) coupled with a strong thermocline, which exists in near-bottom layer along the western margin of Korea Strait, has a low temperature, pH and DO, but abundant nutrients. This water mass disappears in winter owing to strong vertical mixing, and subsequently may act as a pool for nutrients during winter dry-season. On the other hand, vertically well-mixed water column during the winter season was typically occupied by the Tsushima (water mass E) and the coastal water (water mass F) with a development of coastal front formed in a transition zone between them. These winter water masses were characterized by low nutrient concentration and balance in N/P ratio, compared with summer season with high nutrient concentrations and strong N-limitation. Accordingly, the analysis of water masses will help one to better chemical and biological processes in coastal area. In most of the study area, characteristically, the growth of phytoplankton community is limited by nitrogen, which is clearly different with coastal environment of West Sea of Korea, with a relative lack of phosphorus. It showed the western and the southern coasts in Korea are substantially different from each other in environmental and ecological characteristics.

• Korean Journal of Remote Sensing
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• v.23 no.6
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• pp.559-566
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• 2007

The generation of precise digital elevation model (DEM) is very important in coastal area where time series are especially required. Although a LIDAR system is useful in coastal regions, it is not yet popular in Korea mainly because of its high surveying cost and national security reasons. Recently, precise DEM has been made using radar interferometry and waterline methods. One of these methods, spaceborne imaging radar interferometry has been widely used to measure the topography and deformation of the Earth. We acquired ALOS PALSAR FBD mode (Fine Beam Dual) data for evaluating the quality of interferograms and their coherency. We attempted to construct DEM using ALOS PALSAR pairs - One pair is 2007/05/22 and 2007/08/22, another pair is 2007/08/22 and 2007/10/22 with respective perpendicular baseline of 820 m, 312m and respective height sensitivity of 75 m and 185m at southern of Ganghwa tidal flat, Siwha- and Hwaong-lake over west coastal of Korea peninsula. Ganghwa tidal flat has low coherence between 0.3 and 0.5 of 2007/05/22 and 2007/08/22 pair. However, Siwha-lake and Hwaong-lake areas have a higher coherence value (From 0.7 and 0.9) than Ganghwa tidal area. The reason of difference coherence value is tidal condition between tidal flat area (Ganghwa) and reclaimed zone (Siwha-lake and Hwaong-lake). Therefore, DEM was constructed by ALOS PALSAR pair over Siwha-lake and Hwaong-lake. If the temporal baseline is enough short to maintain the coherent phases and height sensitivity is enough small, we will be able to successfully construct a precise DEM over coastal area. From now on, more ALOS PALSAR data will be needed to construct precise DEM of West Coast of Korea peninsular.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.9
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• pp.2073-2078
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• 2014

Based on the DGPS radio wave measurement in the coast of the yellow-sea, south-sea and east-sea, the DGPS service regions in the korean coastal ferry route are analyzed in this paper. The impact of obstacles on the propagation due to the archipelago and island regions are measured and analyzed in the point of service region. The ocean-based DGPS reference stations provide the wide DGPS ocean service regions with signal strength more than $40dB{\mu}V/m$ and signal-to-noise ratio more than 10 dB. Based on the overlapping of the service regions between the DGPS reference stations, the DGPS services with good quality are provided in the coastal ferry route segments. In case of regions where the propagation obstacles are scattered, the increasingly good service can be provided under conditions of output power reinforcement and antenna efficiency enhancement.