• Plant Journal
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• v.12 no.3
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• pp.32-38
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• 2016

In this study, the effect of wake on the energy production of a downstream wind turbine was analyzed on the base of operation practices of wind farm in the coastal complex terrain which has 2 row array of wind turbines. And changes in the variation of wind speed and turbulence intensity was analyzed. In case wind turbines are spaced 4-rotor diameter-apart in the prevailing wind direction, reduction in energy production was confirmed due to the decrease of wind speed and the increase of turbulence intensity by wake. Especially a radical change of wind direction caused wind turbine a sudden stop and energy production significantly reduced. It is considered improvement of yaw brake can prevent the sudden stop and increase energy production.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.6
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• pp.63-74
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• 2010

In this study, wetlands and forest vegetation surrounding rail, road of DMZ area and Civilian Control Line were studied as follows: Plant communities hierarchical system of forest vegetation classified according to the results of phytosociological methods of Braun-Blanquet (1964) as; Quercus mongolica community, Quercus mongolica-Quercus variabilis community and Quercus acutissima -Quercus mongolica community. Wetland vegetation major communities; Scirpus wichurae community, Scirpus fluviatilis community, Juncus effusus var. decipiens community, Typha orientalis community, Typha angustata community, Juncus alatus community, Miscanthus sacchariflorus community, Phragmites communis-Miscanthus sacchariflorus community, Hragmites communis community, Phragmites communis-Alnus japonica community, Alnus japonica community, Phragmites japonica community, Salix koreensis community, Prunus padus community, Alnus japonica community, Zizania latifolia community and Amorpha fruticosa community were surveyed. Coastal sand dune vegetation in a DMZ area and the Civilian Control Line was mainly characterized by; Carex pumila, Elymus mollis, Carex kobomugi, Rosa rugosa, Calystegia soldanella, Lathyrus japonica and Aster hispidus, species that are of typically sand dune vegetation.

• ALGAE
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• v.36 no.2
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• pp.91-109
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• 2021

The occurrence of benthic dinoflagellates, many of which are known to be toxic, is a critical concern for scientists, government officers, and people in the aquaculture, dining, and tourism industries. The interest in these dinoflagellates in countries with temperate climate is increasing because tropical or subtropical species introduced into temperate waters by currents are able to survive the winter season in the new environment owing to global warming. Recently, several species from the benthic dinoflagellate genera Amphidinium, Coolia, Ostreopsis, Gambierdiscus, and Prorocentrum have been reported in the waters of the South and East Sea of Korea. The advent of the benthic dinoflagellates in Korean waters is especially important because raw or slightly cooked seaweeds, which may harbor these benthic dinoflagellates, as well as raw fish, which can be potentially intoxicated by phytotoxins produced by some of these benthic dinoflagellates, are part of the daily Korean diet. The recent increase in temperature of Korean coastal waters has allowed for the expansion of benthic dinoflagellate species into these regions. In the present study, we reviewed the species, distribution, and toxicity of the benthic dinoflagellates that have been reported in Korean waters. We also provided an insight into the ecological and socio-economic importance of the occurrence of benthic dinoflagellates in Korean waters.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.51-52
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• 2019

In the past, waves, which are the main external forces acting on marine and coastal structures, have been dealt with only in terms of safety. Recently, various studies have been conducted to define the characteristics of waves in a specific area in order to respond to the increasing demand for diversified marine activities such as ocean energy development and marine leisure sports. Although the characteristics of waves are specific to the site, the available spectrum model proposed in previous studies are limited. In this study, we analyzed the shape of the ocean wave spectrum by comparing it with the standard spectrum model.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.3
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• pp.334-343
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• 2019

The Al-Zour coastal area, located in southern Kuwait, is a region of concentrated industrial water use, seawater intake, and the outfall of existing power plants. The Al-Zour LNG import facility project is ongoing and there are two issues regarding the seawater temperature in this area that must be considered: variations in water temperature under local meteorology and an increase in water temperature due to the expansion of the thermal discharge of expanded power plant. MIKE 3 model was applied to simulate the water temperature from June to July, based on re-analysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF) and the thermal discharge input from adjacent power plants. The annual water temperatures of two candidate locations of the seawater intake for the Al-Zour LNG re-gasification facility were measured in 2017 and compared to the numerical results. It was determined that the daily seawater temperature is mainly affected by thermal plume dispersion oscillating with the phase of the tidal currents. The regional meteorological conditions such as air temperature and tidal currents, also contributed a great deal to the prediction of seawater temperature.

• Journal of the Korean Geosynthetics Society
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• v.14 no.4
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• pp.59-77
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• 2015

In order to meet the new requirements for landfill materials, this study planned a study to apply mixed soil of mixing bottom ash and coastal dredged soil to the dredged ground. Coal ash generated from thermal power plant is divided into fly ash and bottom ash. In the case of fly ash, many studies have been conducted because small particles causes permeability coefficient to be small during recycling so no problem has been raised in the environmental area but the utilization of bottom ash has been limited because environmental problems have been raised during recycling due to its larger particle size and greater permeability coefficient. According to recently published studies, however, the results of the study that conducted the water analysis of leachate generated in the ground improvement section using bottom ash showed that heavy metal contamination levels were found to be within the reference value and no significant environmental problems were found so utilization of bottom ash is evaluated to increase significantly in the future. This bottom ash has the particle size of sand and only transportation costs need to be considered when providing materials because the majority has been disposed and it is judged as the most suitable material in dredging landfill in the economic aspect because most thermal power plants are located in the coast and transportation costs can be reduced by ship. Also, research on mixed soil that can maximize the effect of the construction period and construction cost savings than dredged soil is determined as needed because the demand for coastal dredging reclamation is increasing such as Saemangeum project etc. Therefore, we studied self-weight consolidation characteristics depending on sample processing and mixing method of mixed soil by carrying out interior self-weight consolidation experiments on mixed soil of mixing bottom ash and Kaolinite according to the new development needs of recent coastal reclaimed ground and these result findings are expected to be used as basic data when applying the large coastal dredged ground in the future.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.1
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• pp.49-64
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• 2014

Seabed beneath and near the coastal structures may undergo large excess pore water pressure composed of oscillatory and residual components in the case of long durations of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. If the liquefaction occurs in the seabed, the structure may sink, overturn, and eventually fail. Especially, the seabed liquefaction behavior beneath a gravity-based structure under wave loading should be evaluated and considered for design purpose. In this study, to evaluate the liquefaction potential on the seabed, numerical analysis was conducted using 2-dimensional numerical wave tank. The 2-dimensional numerical wave tank was expanded to account for irregular wave fields, and to calculate the dynamic wave pressure and water particle velocity acting on the seabed and the surface boundary of the structure. The simulation results of the wave pressure and the shear stress induced by water particle velocity were used as inputs to a FLIP(Finite element analysis LIquefaction Program). Then, the FLIP evaluated the time and spatial variations in excess pore water pressure, effective stress and liquefaction potential in the seabed. Additionally, the deformation of the seabed and the displacement of the structure as a function of time were quantitatively evaluated. From the analysis, when the shear stress was considered, the liquefaction at the seabed in front of the structure was identified. Since the liquefied seabed particles have no resistance force, scour can possibly occur on the seabed. Therefore, the strength decrease of the seabed at the front of the structure due to high wave loading for the longer period of time such as a storm can increase the structural motion and consequently influence the stability of the structure.

• Korean Journal of Medicinal Crop Science
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• v.5 no.3
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• pp.202-205
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• 1997

This study was carried out to determine the effect of sowing time on the flowering, growth and yield of Scutellaria baicalensis Georg, which was collected from Yeochon district, cultivated after barley in the southern coastal areas of Korea. Emergence and flowering dates in the sowing time of June 1 were earlier than those of the other sowing times. In the sowing time of June 1, length and diameter of main stem, number of node per main stem, number of branch per plant and dry weight of stem leaves were greater than those of sowing times of June 10 and June 20. Yield components such as main stem length and diameter, main stem numbers, branches per plant, dry weight of stem leaves, main root length and thickness, number of large root and fine root per plant, and dry weight of root were the highest at the sowing time of June I as the yield of 71.3kg/10a. Optimum sowing time of Scutellaria baicalensis Georg cultivated after barley was June 1 in southern areas of korea.

• Journal of Environmental Impact Assessment
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• v.26 no.1
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• pp.78-92
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• 2017

Environmental impact assessment(EIA) on the construction and operation of thermal power plant(TPP) is aimed at promoting sustainable coastal development by clearly identifying the marine physics and organisms effects of the project on the surrounding marine environment and minimizing its impact. The primary purpose of this study is to establish EIA guidelines for TPP in order to assess how TPP construction projects influence marine environment and to establish the mitigaion plans of environmental impacts. Through this study, scientific and efficient EIA guidelines for the marine environments were established by a specialist forum consisted of officials from the Ministry of Environment and the Ministry of Trade, Industry and Energy, personnel from five public corporations in charge of TPPs and marine environment experts. In the study, fifteen EIA reports (2009~2015) on TPPs submitted were analyzed to identify the shortcomings of current assessment items on marine environment and to collect a wide range of information including EIA report formulation regulations, domestic and overseas environmental survey guidelines and EIA review comments on TPPs. Based on the findings, a specialist forum put together EIA guidelines for TPP construction projects.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.155-167
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• 2007

This study was carried out to offer the raw data for environment conservation by surveying and analysing the flora distributed over Jinhae-si, and to present the frame for preparing the method of obtaining the bioresource in approach to plant resource. The period of survey was from May, 2005 to June, 2006, and the routes were A(Mt. Jangbok), B(Ahnmin hill) C(Mt. Hwa). The results as follows. The vascular plants were summarized as 447 taxa; 98 families, 286 genera, 394 species, 49 varieties, and 4 forma. The rare plants designated by Korea Forest Service were 2 taxa; Tricyrtis dilatata and Viola albida. The Korean endemic plants were 11 taxa; Tricyrtis dilatata, Salix caprea, Carpinus coreana, Melandryum seoulense, Clematis trichotoma, Thalictrum uchiyamai, Deutzia coreana, Spiraea prunifolia for. simpliciflora, Lespedeza maritima, Forsythia koreana and Weigela subsessilis.