• The Journal of Engineering Geology
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• v.25 no.4
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• pp.485-498
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• 2015

Structural analysis for a large-scale fault in Maegok-dong, Ulsan, was carried out based on filed-works to investigate the geometric and kinematic characteristics of the fault as well as its Quaternary slip. As results, a series of repeated stratigraphy, minor faults, fracture zones, and deformation band clusters are observed over a distance of about 100 m in the first studied site consisting of sedimentary rocks, which may indicate the damage zone of a large-scale fault in this site. In the second site, mainly composed of granitic clastic rocks, a large-scale thrust fault is expected based on low-angle dipping faults showing branched and/or merged patterns. Age of the last slip on this fault was restrained as after 33,275 ± 355 yr BP based on radiocarbon dating for organic material included in the gouge zone. Dimension of fault damage zone, dominant sense of slip, and age of the slip event associated with the fault suggest that these structures have a close relationship with the Ulsan Fault and/or Yeonil Tectonic Line, which are well-known large-scale neotectonic structural features around the study area. Therefore, it is necessary to study the characteristics of the faults in detail based on structural geology and paleoseismology in order to ensure seismic and geologic stability of the buildings under construction, and to prevent geologic hazards in this area.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.386-400
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• 2022

Seismic fragility analysis, a part of seismic probabilistic risk assessment (SPRA), is commonly used to establish the relationship between a representative property of earthquakes and the failure probability of a structure, component, or system. Current guidelines on the SPRA of nuclear power plants (NPPs) used worldwide mainly reflect the earthquake characteristics of the western United States. However, different earthquake characteristics may have a significant impact on the seismic fragility of a structure. Given the concern, this study aimed to investigate the effects of earthquake characteristics on the seismic fragility of concrete containments housing the OPR-1000 reactor. Earthquake time histories were created from 30 ground motions (including those of the 2016 Gyeongju earthquake) by spectral matching to the site-specific response spectrum of Hanbit nuclear power plants in South Korea. Fragility curves of the containment structure were determined under the linear response history analysis using a lumped-mass stick model and 30 ground motions, and were compared in terms of earthquake characteristics. The results showed that the median capacity and high confidence of low probability of failure (HCLPF) tended to highly depend on the sustained maximum acceleration (SMA), and increase when using the time histories which have lower SMA compared with the others.

• Journal of Environmental Impact Assessment
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• v.8 no.2
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• pp.21-29
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• 1999

This study was conducted to investigate the characteristics of surface ozone concentration and occurrence of high ozone concentration using hourly ozone and meteorological data of 1997~1998 in Pusan coastal area. Monthly mean ozone concentration was highest in Spring(35.4ppb) and lowest in Winter(22.2ppb). Relative standard deviation indicating clearness of observation site was 0.42 that is similar to urban area. The diurnal variation of ozone concentration of Dongsamdong showed maximum at 15~16LST and minimum 07~08LST that typical pattern of ozone concentration. In ozone episode period(May 18~23, 1998), diurnal change of ozone concentration was very high, and ozone concentration was related to meteorological parameters such as temperature, relative humidity, wind speed, cloud amount and radiation on a horizontal surface.

• Corrosion Science and Technology
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• v.7 no.2
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• pp.125-129
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• 2008

Results of corrosion testing for different grades of titanium, copper, zinc, alluminium alloys and steels after two years of outdoor exposure under humid tropical urban and marine conditions have been presented and discussed. Mass loss and corrosion product characteristics for the exposed specimens at Hanoi testing site with high humidity and Nhatrang marine stations (at 100 and 1,000 meters distances from sea) with different airborne salinities (35.9 and $90.0mg/m^2.d$ respectively) have been selected for investigation. From time dependence of the specimen mass loss and corrosion product characteristics, the strong influence of environmental parameters upon durability for the investigated metals and alloys has been demonstrated. Only titanium alloys show high resistance to the marine conditions. All the other specimens (copper, zinc, alluminium alloys and steels) have been underwent strong deterioration under influence of aerosol salinity. Results of corrosion products analysis have been also presented for characterization of environmental impact on the metal degradation processes.

• Korean Institute of Interior Design Journal
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• no.26
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• pp.104-111
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• 2001

This study deals with the expressive characteristics of Installation Art and their applicability to environmental design, and as such, aims to specify a artistic methods from the contemporary art. What Installation Art is search of in their works is "the state of relationships" which is "to replace the concept of form with that of structure, and the concept of space with that of the environment" that is, the terms of relations in the overall environment of time and space. Installation Art essentially relies on a multiplicity of forms and attitudes leading to projects which positively make use of "spatial-temporal process" to reaffirm and "problematise" their open-endedness manifest in complex contextuality and shifting temporality. This study presents a new interpretation of spatial-temporal dimension, site-specificity, and intermedia art that we find in Installation Art and tries to combine that new artistic insight a with environmental design to provide a basis for integrated art. This study places a great emphasis on the interdisciplinary approaches to the environment we inhabit, which I hope will contribute to generating a greater number of creative possibilities for environmental design.

• Journal of Environmental Science International
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• v.32 no.1
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• pp.37-46
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• 2023

This study investigated the effect of May 31, 2022 Miryang wildfire on fine particle concentrations in Busan and Gimhae, which are neighboring urban areas. In addition, fine particle characteristics and air pollution concentrations were investigated in Miryang, where haze occurred. The Miryang city wildfire that occurred on May 31, 2022, at 0925 LST, was driven by strong north winds and increased fine particle concentrations in Dongsangdong and Jangyoodong, Gimhae City, which are approximately 35 km to the southeast and south, respectively, of the wildfire occurrence site. Furthermore, the fine particle concentration in Myeongjidong, which is approximately 50 km south-southeast of the wildfire site, exhibited a temporary increase at 1400 LST owing to the effects of wildfire smoke. On the morning of June 1, the day after the fire, the Miryang area had very bad visibility because of the smoke from the fire. Therefore the PM₁₀ and PM_2.5 concentrations in Naeildong, 3 km south of the wildfire site, were 276 ㎍/㎥ and 222 ㎍/㎥, respectively, at 1200 LST. In addition, the gases O₃, CO, and SO₂ showed high concentrations at the time of haze generation. This study provides insights into policy making in response to the rapid increase in fine dust when wildfire occurs near cities.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.300-306
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• 2007

This study was carried out to analyze the characteristics of forest environmental and stream morphological factors by using the quantification theory (I) for prediction of the suitable dam site. The results obtained from this study were summarized as follows; The selection of suitable site for erosion control dam was estimated by normalized score of each category. And the prediction method of suitable site for erosion control dam divided into class I (Very suitable site), II (Suitable site), and III (Poor suitable site) for the convenience of use. In conclusion, if we select the suitable site for construction of erosion control dam for disaster prevention, we could save the loss of tremendous budget, avoid the poor suitable site due to subjective judgment, and it would promote the functions of erosion control dam.

• Journal of the Korean Geotechnical Society
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• v.28 no.3
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• pp.25-34
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• 2012

In order to verify that the recently proposed two-parameters site classification system and the corresponding site coefficients are suitable for the local geological conditions in Korea, a comparison was conducted with current Korean seismic code, Eurocode-8, NYC DOT seismic code. The design spectrum of the current Korean seismic code is significantly amplified in the long-period range, whereas the other response spectra, including the proposed two-parameters approach, are significantly amplified in the short-period range, which is a typical geological condition in Korea. In addition, based on the results of site response analyses in the specific $10km{\times}10km$ area of Gyeongju, spatial distributions of site coefficients from site-specific seismic response analyses were compared with the proposed site coefficients, as well as those specified in the current Korean seismic code. The site coefficients ($F_a$ and $F_v$) from the current Korean seismic codes show significantly high spatial error distributions compared with those specified by the two-parameters site classification system. Therefore, the proposed system is suitable for regions of shallow bedrock including the Korean peninsula.

• Journal of Environmental Impact Assessment
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• v.20 no.1
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• pp.13-24
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• 2011

This study was carried out to analyze ecological characteristics and select target species for effective restoration plans of wildlife corridors at Galmachi of Sungnam City. The actual vegetation in study area was physiognomically mixed with deciduous broad leaved forests dominated by oaks and artificially planted species. And it is a secondary forest formatted by sprout originated stand and being on early succession stage as a young stand. So study site was regarded as not suitable for the habitats for wildlife. The number of mammal species at study site was total 22 species, but most of these species were found as not so many in individual numbers. The individual number of hare was approximately 4 to 8, while the raccoon dog and water deer with 2 to 3 and 1 to 2, respectively. As such, it was estimated as a low population density due to discontinuation of ecosystem and the man-made impacts. In this study, raccoon dog and water deer were selected as the target species because of their migration patterns and ecological value in local ecosystem. It was suggested to establish a wildlife corridors of an over-bridge type at the peak area of Galmachi, known to be the mostly-used migratory route for 2 target species.

• Journal of Environmental Science International
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• v.9 no.6
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• pp.483-488
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• 2000

In this study, the distribution characteristics of volatile organic compounds (VOCs) were investigated on the seasonal basis across spring, summer, and fall during the year of 1998. According to this analysis, most VOC species investigated exhibited strong temporal trends. Over diurnal scale, there distribution characteristics were affected by seasonal factors strongly. While they showed high day/night ratio pattern during spring, the pattern was reversed during fall. When the seasonal mean values were compared between the two seasons, the spring values were systematically higher than their counterparts in most cases. In addition when our VOC measurement date were compared with those reported from elsewhere, we were able to conclude that the VOC levels in the study area are comparable to the level weakly impacted by the regional emissions of VOCs. Although our data are not sufficient enough to systematically explain the atmospheric distribution and behavior of VOCs, the findings of strong correlations among some of VOC species suggests strong need for investigating their interactions in the earth\`s atmosphere.