• Journal of Radiation Protection and Research
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• v.22 no.4
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• pp.273-288
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• 1997

A three dimensional sea-land breeze model and Lagrangian particle dispersion model have been employed for the study on the mesoscale atmospheric dispersion of radioactive materials released from Wolsung NPPs. In this study, atmospheric dispersion simulations are carried out under two synoptic weather conditions : the geostrophic flow is a weak northerly wind(CASE 1) and a strong northerly wind(CASE 2) on a clear day in spring. The results show that atmospheric dispersion is affected by sea-land breeze and the recirculation of particles by the change of wind direction between sea breeze and land breeze plays an important role in atmospheric concentration distribution of radoactive materials.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.6
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• pp.481-492
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• 2009

The characteristic of cold water by upwelling in the southeast of the Korean Peninsula and the effect of sea breeze in this region are investigated. The coastal upwelling around the southeast coast of the Korea Peninsula is analyzed by using Coastal Oceanographic Data statistical analyses for 5 years were carried out. The period of an cold water event, on the average, was observed southwesterly wind events. The analysis suggests that strong and persistent southwesterly winds in period of an cold water play an important role of bring the moisture to the surface, generating persistent cyclone as jangma. In order to investigate the effect of cold water on sea breeze, we considered two case. First, Exp. 1 is not occurred coastal upwelling on sea breeze. Second, Exp. 2 is occurred cold water on sea breeze. Two experiments were completed separately to the effects of cold water by upwelling. The results show the sea breeze is stronger in Exp. 2, when the cold water occurs, and weaker in Exp. 1, when there is no cold water. In order to verify the effect of the sea breeze on the cold water by upwelling, on the intensification and change of direction of the prevailing wind, the sea breeze effectively intensify cold water condition.

• Explosives and Blasting
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• v.37 no.1
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• pp.34-47
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• 2019

This case study is concerned with the project of the explosive demolition for the DCRE Incheon plant located in Hakik district in Incheon city. The building was severely aging due to the high temperature and sea winds of hundreds of degrees emitted by chimney-shaped steel structures inside the building. Due to this, the concrete of the column and the beam fell off and rusted rebar were exposed, and some of the slabs were severely damaged, making it difficult for workers to access the structure. Therefore, it is not possible to apply a mechanical demolition method in which heavy equipment enters the interior of the building, and an explosive demolition method was applied to allow the building to be demolished without dismantling the internal facilities of the building. The order of blasting proceeded in the order of (1) building ${\rightarrow}$ (2) chimney 2 ${\rightarrow}$ (3) chimney 1. A total of 406 electronic detonators (Unitronic 600) was used to sequentially initiate the explosives installed at appropriate in building and chimneys.

• Atmosphere
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• v.29 no.1
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• pp.41-51
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• 2019

The characteristics of the sea breeze were investigated using the wind and temperature data collected from 300-m tower at Boseong from May 2014 to April 2018. Sea breeze day was detected using following criteria: 1) the presence of a clear change in wind direction near sunrise (between 1 hour after sunrise and 5 hours before sunset) and sunset (from 1500 LST to midnight), 2) presence of thermal forcing of sea breeze and 3) no heavy precipitation (rain < $10mm\;d^{-1}$). Sea breeze days occurred on 569 days for 4 years. The monthly distribution of sea breeze day occurrence shows maxima in May and September and minimum in December. The average onset and cessation times of the sea breeze are 0942 LST and 1802 LST, respectively. Although the 10-m wind shows clockwise rotation with time in the afternoon, the observed hodograph does not show an ideal elliptical shape and has different characteristics depending on the upper synoptic wind direction. Vertical structure of sea breeze shows local maximum of wind speed and local minimum of virtual potential temperature at 40 m in the afternoon for most synoptic conditions except for southeasterly synoptic wind ($60^{\circ}{\sim}150^{\circ}$) which is in the same direction as onshore flow. The local minimum of temperature is due to cold advection by sea breeze. During daytime, the intensity of inversion layer above 40 m is strongest in westerly synoptic wind ($240^{\circ}{\sim}330^{\circ}$) which is in the opposite direction to onshore flow.

• Journal of Environmental Science International
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• v.30 no.6
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• pp.465-474
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• 2021

This research investigated the characteristics of fine particle concentration and ionic elements of PM_2.5 during sea breeze occurrences during summertime in Busan. The PM₁₀ and PM_2.5 concentrations of summertime sea breeze occurrence days in Busan were 46.5 ㎍/m³ and 34.9 ㎍/m³, respectively. The PM₁₀ and PM_2.5 concentrations of summertime non-sea breeze occurrence days in Busan were 25.3 ㎍/m³ and 14.3 ㎍/m³, respectively. The PM_2.5/PM₁₀ ratios of sea breeze occurrence days and non-sea breeze occurrence days were 0.74 and 0.55, respectively. The SO₄^2-, NH₄⁺, and NO₃^- concentrations in PM_2.5 of sea breeze occurrence days were 9.20 ㎍/m³, 4.26 ㎍/m³, and 3.18 ㎍/m³ respectively. The sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR) of sea breeze occurrence days were 0.33 and 0.05, respectively. These results indicated that understanding the fine particle concentration and ionic elements of PM_2.5 during sea breeze summertime conditions can provide insights useful for establishing a control strategy of urban air quality.

• Journal of Environmental Impact Assessment
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• v.31 no.5
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• pp.334-342
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• 2022

The stringent air environment conservation act forced to build an indoor dome for coal storage. However, it causes some problems due to accumulation of fly ash and harmful substances inside. To solve this problem, this study analyzed the pattern of internal airflow and the amount of ventilation for an indoor coal yard. Overall, the airflow inside the indoor coal yard tended to move to the southwest facing the mountain. In addition, sea-breeze was blowing from the northern louver window facing the sea, where airflow was flowing in. The total flow rate flowing into the indoor coal yard was 918,691 m³/h, and the number of natural ventilation per hour was 0.6 times. Therefore, it is proposed to install a forced ventilation device at the location where internal air flow is concentrated.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.4
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• pp.247-258
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• 2023

Purpose : This study aims to evaluate the effectiveness of a sea breeze walking program by analyzing the metabolic disease-related, immune-inflammation-related, and respiratory health-related variables of the test subjects associated with improved respiratory health. Methods : In the experiment, 30 patients with metabolic diseases were divided into an experimental group (n=15) and a control group (n=15). The experimental group walked on the Namparang-gil, Geoje trail, while the control group walked on the Hoeya-cheon, Yangsan trail. Both groups participated in the same walking program for two hours, twice a week for four weeks. Thereafter, the metabolic disease-related, immune inflammation-related, and respiratory health-related variables were measured and compared between the two groups. Results : After the four-week sea breeze walking program, in terms of changes in the metabolic disease-related variable, a statistically significant interactive effect was found in waist circumference (p<.001). The experimental group showed a significant decrease in waist circumference after the program. After the four-week sea breeze walking program, the control group showed a statistically higher increase in lactic acid (p.<05), whereas the experimental group exhibited a decrease in lactic acid. For the respiratory health-related variables, no statistically significant differences were found after the sea breeze walking program. However, the experimental group showed an increase in FEV1,while the control group showed a decrease in FEV1. For the maximum oxygen intake, no statistically significant interactive differences were found but there was a statistically significant effect in time (p<.05). The two groups exhibited an increase in maximum oxygen intake. Conclusion : After the sea breeze walking program, positive physical changes were observed in the metabolic disease-related and immune inflammation-related variables.

• Korean Journal of Environment and Ecology
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• v.16 no.1
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• pp.10-21
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• 2002

This study was intended to investigate injury rates of landscape trees planted in the reclaimed seaside areas and to analyse their causes in planting environment. The planting environment such as soil properties, reclaimed depth of soil, soil hardness, salt consistency of soil, and drainage system were surveyed in 8 reclaimed seaside areas in the middle and southern regions of the country. Injury rates of 42 species, 1,233 trees and growth of branches in 6 species. 130 trees were measured and analysed to fond out salt-resistant trees in the reclaimed lands. The results of the survey are as follows; the average injury rate of evergreen trees was 32%. which was much lower than that of deciduous trees as 52%. The lower injured trees in the 8 reclaimed lands were Pinus thunbergii, Pinus parvinora. Juniperus chinensis 'Kaizuka', Pinus koraiensis, Acer trifdum, Koelreuteria paniculata and Metasequoia glyptostroboides. The higher injured trees were Acer palmatum, Magnolia kobus. Lagerstroemia indica, Diospiros kaki, Cercidiphyllum japonicum, Sorbus commixta, Prunus yedoensis, Pinus desinora, Chaenomeles sinensis, Albizzia julibrissin and Zelkowa serrata. At least the mounding of 1.7m depth of soil is needed from the tidal saline soil to the roots of trees to protect trees from salt injury Roots of trees were found to have infiltrated to 0.77m under the soil of which solidity was over 4.5kg/㎥. And 22 of total 25 soils were acid from pH 3.72 to pH 5.85. Injury rate of trees was much higher when they were detached from the sea, and planted on the drainage.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.1-6
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• 1984

Soils in Cheju Island, derived mostly from volcanic ashes, were collected for chemical analysis to determine the effect of land utilization pattern on soil chemical characteristics. The coastal area has long been used for intensive farming and some of the mid-mountain region were recently reclaimed for agricultural crop production. The cation exchange capacity and the organic matter in the soils increased in the order of coastal area < mid-mountain belt < upper mountain area, while pH, base saturation, available phosphorus and exchangeable bases decreased with the elevation. Generally, the organic matter, the cation exchange capacity and the exchangeable bases of the Cheju soils were found to be considerably higher than the Korean mainland soils. However, the base saturation and the available phosphorus were far below the mainland average. The ratio of monovalent basic cations to total exchangeable bases showed the highest in the soils of the mountain belts and the lowest in the coastal area soils. These data suggest that a higher soil pH in the coastal area as compared to the mountainous slopes has resulted not from the sea water but from continuous application of alkaline fertilizers and times.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.375-382
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• 2014

The objective of this study was to investigate suitable plantation site for planted Chamaecyparis obtusa seedlings from the analysis of regional early growth performances. Two years old C. obtusa seedlings were planted with the density of $3,900seedlings{\cdot}ha^{-1}$ in late March, 2011 at Haeman and Jangseong, Jeollanamdo. In each study site, three plots ($400m^2$ per plot) were established and root collar diameter (mm) and tree height (cm) of each C. obtusa were measured in April, 2011 and October from 2011 to 2013. We also analyzed soil physical and chemical properties of sites and compartmental nitrogen and phosphorus concentrations of C. obtusa. Although the concentrations of soil nitrogen, organic matter, and C.E.C. at Haenam site were higher than those at Jangseong site, early growth performances of planted C. obtusa at Jangseong site were significantly better than those at Haenam site. The reasons for these results were probably related to deep available soil depth at Jangseong site and relatively low annual precipitation and sea wind at Haenam site, which was adjacent to the sea. The compartmental nitrogen and phosphorus concentrations of C. obtusa was in the order of needles > current twigs > fine root > stem and branches root above 2 mm in diameter. The phosphorus concentration of needles at Haenam site was significantly higher than that at Jangseong site. The results of this study might be useful for the selection of suitable plantation site for C. obtusa.