• Special Issue of the Society of Naval Architects of Korea
• /
• 2009.09a
• /
• pp.6-17
• /
• 2009

The present paper addresses development of a GTT NO96 membrane type 170K m3 LNG carrier targeted to operate in moderate ice infested seas including Baltic Sea, Sakhalin port of Sea of Okhotsk, Murmansk port of Barents Sea, etc. Critical design issues are covered in detail to meet the requirements coming from the missioned operation conditions comprising low design ambient temperature, harsh wave conditions, stringent environmental protection policies, etc.

• Korean Journal of Remote Sensing
• /
• v.36 no.1
• /
• pp.41-53
• /
• 2020

The production of near- and off-shore fisheries in South Korea is decreasing due to rapid changes in the fishing environment, particularly including higher sea temperature in recent years. To improve the competitiveness of the fisheries, it is necessary to provide fish catch information that changes spatiotemporally according to the sea state. In this study, artificial intelligence models that predict the CPUE (catch per unit effort) of mackerel, anchovies, and squid (Todarodes pacificus), which are three major fish species in the near- and off-shore areas of South Korea, on a 15-km grid and daily basis were developed. The models were trained and validated using the sea surface temperature, rainfall, relative humidity, pressure,sea surface wind velocity, significant wave height, and salinity as input data, and the fish catch statistics of Suhyup (National Federation of Fisheries Cooperatives) as observed data. The 10-fold blind test results showed that the developed artificial intelligence models exhibited accuracy with a corresponding correlation coefficient of 0.86. It is expected that the fish catch models can be actually operated with high accuracy under various sea conditions if high-quality large-volume data are available.

• Korean Journal of Environmental Biology
• /
• v.21 no.2
• /
• pp.101-113
• /
• 2003

The spatial distributional pattern of macrobenthic fauna was investigated to assess the summer benthic environmental conditions in Gwangyang Bay, the southern coast of Korea. The macrobenthic faunal community from 38 sites in Gwangyang Bay comprised 154 species and showed an overall mean density of 1,280 individuals $m^{-2}$. Polychaetes were the most important component of the macrofaunal community in species richness, abundance and biomass. The dominant species in abundance were polychaetes like Tharyx sp. (44.8%), Lumbrineris longifolia (14.0%), Heteromastus filiformis (3.6%), a mussel Mytilus edulis, and an amphipod crustacean Corophium sinense. The abundance and biomass in the western part of the bay were lower than those in the channel regions and mouth of the bay. The community indices showed the same trend in the spatial distribution with the abundance and species richness. All macrobenthic faunas were assigned into a specific functional group according to their ecological responses to the environmental stress. The benthic community health based on the Benthic Pollution Index (BPI) or Biotic Coefficient (BC) seemed to be in the normal to unbalanced er transitional condition, indicated by the dominance of small polychaete worms like Tharyx sp. in the mouth part of the bay.

• Fisheries and Aquatic Sciences
• /
• v.10 no.4
• /
• pp.215-219
• /
• 2007

Long-tenn variation in krill (Euphausia superba) and salp (mainly Salpa thompsoni) stocks was compared to environmental changes in the Atlantic and Indian sectors of the Antarctic. Environmental conditions examined were air temperature, water temperature, salinity, and sea-ice extent from 1926 to 1938 and from 1982 to 2000. The long-term pattern of krill was opposite to that of salp: krill stock decreased while salp stock increased concurrently. Krill stock was about three-fold higher from 1926 to 1938 than from 1982 to 2000, but salp was about four -fold lower in 1926-1938 than in 1982-2000. A wanning trend was observed in the environmental data, and the long-term variation in krill and salp stocks was affected by this trend.

• Journal of Environmental Impact Assessment
• /
• v.14 no.5
• /
• pp.275-289
• /
• 2005

In Korea, health-related items under current EIA (Environmental Impact Assessment) system can only be found in the categories of hygiene and public health. However, environment and public health are not adequately connected and also health is underestimated even though health is an important component of environmental assessments. As a result, health is not well integrated within criteria for investigating the impacts on environment. International trends in HIA (Health Impact Assessment) to strengthen the connection between environment and health were investigated in this research. Definitions, functions, circumstances, and merits of HIA in foreign countries were compared. By collecting and analyzing international organizations' and other countries' data related with HIA and EIA, preceding conditions and execution plans were suggested to link EIA and HIA from SEA (Strategic Environmental Assessment) aspects and to successfully accomplish EIA in Korea. According to this research, EHIA (Environmental Health Impact Assessment) can predict and manage the results of economical development only under the principles of inhabitants' participation, sustainability, and social justice. EHIA should be modified and improved towards increasing regional and national capabilities. For this, preparation of adequate procedure is required to connect EIA and HIA.

• Journal of Environmental Science International
• /
• v.9 no.1
• /
• pp.19-25
• /
• 2000

As the tideland reclamation is done on a large scale these days, construction work is active in the coastal areas. Facilities in the coastal areas must be built with the tide characteristics taken into consideration. Thus the tide characteristics affect the overall reclamation plan. The analysis of the tide data boils down to a harmonic analysis of the hourly changes of long-term tide data and extraction of unharmonic coefficients from the results. Since considerable amount of tide data of the West Coast are available, the existing data can be collected and can be used to obtain the temporal changes of the tide by being fitted into the tide prediction model. The goal of this thesis lies in assessing whether the mean sea level used in the field agrees with the analysis results from the long-term observation data obtained with their homogeneity guaranteed. To achieve this goal, the research was conducted as follows. First the present conditions of the observation stations, the land level standard, and the sea level standard were analyzed to set up a time series model formula for representing them. To secure the homogeneity of the time series, each component was separated. Lastly the mean sea level used in the field was assessed based on the results obtained form the analysis of the time series.

• Journal of Korean Society for Atmospheric Environment
• /
• v.26 no.2
• /
• pp.137-150
• /
• 2010

A meso-urban meteorological model (Urbanized MM5; uMM5) with urban canopy parameterization (UCP) was applied to the high-resolution simulation of meteorological fields in a complex coastal urban area and the assessment of urban impacts. Multi-scale simulations with the uMM5 in the innermost domain (1-km resolution) covering the Busan metropolitan region were performed during a typical sea breeze episode (4~8 August 2006) with detailed fine-resolution inputs (urban morphology, land-use/land-cover sub-grid distribution, and high-quality digital elevation model data sets). An additional simulation using the standard MM5 was also conducted to identify the effects of urban surface properties under urban meteorological conditions. Results showed that the uMM5 reproduced well the urban thermal and dynamic environment and captured well the observed feature of sea breeze. When comparison with simulations of the standard MM5, it was found that the uMM5 better reproduced urban impacts on temperature (especially at nighttime) and urban wind flows: roughness-induced deceleration and UHI (Urban Heat Island)-induced convergence.

• Journal of Korean Society on Water Environment
• /
• v.23 no.1
• /
• pp.12-18
• /
• 2007

Difference of total coliforms (TC) survival time of mixed samples (effluent were mixed by seawater or freshwater) were examined in various conditions. The time taken to achieve a 90% reduction in the TC concentration ($T_{90}$) of effluent, high initial TC concentration and low initial TC concentration samples indicated 143.9, 121.9 and 89.6 hours at $25^{\circ}C$, respectively. At $4^{\circ}C$, log removal rate after 336 hours were 0.96, 1.04, and 1.30. TC survival time of effluent-inoculated seawater sample was longer than that of effluent-inoculated freshwater sample in laboratory. At outdoor condition, TC inactivation curves of effluent-inoculated seawater or freshwater samples showed similar patterns. And both of them were greatly influenced by climate condition. There was not enough evidence that TC survived longer in freshwater than sea water. It was unlikely that the salinity of sea water contributed to the inactivation process of TC.

• Atmosphere
• /
• v.28 no.2
• /
• pp.153-162
• /
• 2018

The statistical prediction model for wintertime surface air temperature, that is based on snow cover extent and Arctic sea ice concentration, is updated by considering $El-Ni{\tilde{n}}o$ Southern Oscillation (ENSO) and Quasi-Biennial Oscillation (QBO). These additional factors, representing leading modes of interannual variability in the troposphere and stratosphere, enhance the seasonal prediction over the Northern Hemispheric surface air temperature, even though their impacts are dependent on the predicted month and region. In particular, the prediction of Korean surface air temperature in midwinter is substantially improved. In December, ENSO improved about 10% of prediction skill compared without it. In January, ENSO and QBO jointly helped to enhance prediction skill up to 36%. These results suggest that wintertime surface air temperature in Korea can be better predicted by considering not only high-latitude surface conditions (i.e., Eurasian snow cover extent and Arctic sea ice concentration) but also equatorial sea surface temperature and stratospheric circulation.

• Atmosphere
• /
• v.23 no.1
• /
• pp.73-83
• /
• 2013

In recent several years, East Asia, Europe and North America have suffered successive cold winters and a number of historical records on the extreme weathers are replaced with new record-breaking cold events. As a possible explanation, several studies suggested that cryospheric conditions of Northern Hemisphere (NH), i.e. Arctic sea-ice and snow cover over northern part of major continents, are changing significantly and now play an active role for modulating midlatitude atmospheric circulation patterns that could bring cold winters for some regions in midlatitude. In this study, a dynamical seasonal prediction system for NH winter is newly developed using the snow depth initialization technique and statistically predicted sea-ice boundary condition. Since the snow depth shows largest variability in October, entire period of October has been utilized as a training period for the land surface initialization and model land surface during the period is continuously forced by the observed daily atmospheric conditions and snow depths. A simple persistent anomaly decaying toward an averaged sea-ice condition has been used for the statistical prediction of sea-ice boundary conditions. The constructed dynamical prediction system has been tested for winter 2012/13 starting at November 1 using 16 different initial conditions and the results are discussed. Implications and a future direction for further development are also described.