• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.986-993
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• 2010

Spatially distributed on-site devices such as bioretentions and bioboxfilters are becoming more common as a means of controlling urban stormwater quality. One approach to modeling the cumulative catchment-scale effects of such devices is to resolve the catchment down to the scale of a land parcel or finer, and then to model each device separately. The focus of this study is to propose a semi-distributed model for simulating urban stormwater quantity and identifying best sites for spatially distributed on-site stormwater control devices in an urban drainage system. A detailed model for urban stormwater improvement conceptualization simulation is set up for a $0.9342km^2$.

• Journal of Soil and Groundwater Environment
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• v.21 no.6
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• pp.14-21
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• 2016

This study evaluated the applicability of stabilization of arsenic (As)-contaminated soil with iron (Fe) oxides at the former Janghang smelter site. Three Fe oxides (magnetite, goethite, and hematite) were tested as stabilizing agents to one soil sample collected from the study site. Amendment of 5% of magnetite, goethite, or hematite for one week showed the 64, 58, and 36% of reduction of the SBRC (Solubility/Bioavailability Research Consortium)-extractable (bioaccessible) As, respectively. Duration of stabilization more than one week did not show an additional reduction in SBRC-extractable As. Amendment of 5% of magnetite, which showed the highest As stabilization efficiency, was applied to 24 soil samples collected from the same site for one week, and 72% of reduction in the bioaccessible As was observed. The potential carcinogenic human health risk at the study site caused by As was $1.7{\times}10^{-5}$, which could be reduced to $8.1{\times}10^{-6}$ by the amendment of 5% magnetite for one week.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1318-1327
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• 2008

Geotechnical sites in urban areas may have embedded structures such as utility lines and underground concrete structures, which cause difficulties in site investigation. This study is a preliminary research to establish knowledge base for developing an optimal technique for site investigation in urban areas. Surface-wave method and resistivity survey, which are frequently adopted for non-destructive site-investigation for geotechnical sites, were investigated to characterize effects of adjacent structures. In case of surface wave method, patterns of wave propagation were investigated for typical sets of multi-layered geotechnical profiles by numerical simulation based on forward modeling theory and field experiments for small-size model tests and real-scale tests in the field. In case of resistivity survey, 3-D finite element analyses and field tests were performed to investigate effects of adjacent concrete structures. These theoretical and experimental researches for surface-wave method and resistivity survey resulted in establishing physical criteria to cause interference of adjacent structures in site investigation at urban areas.

• Transactions on Electrical and Electronic Materials
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• v.11 no.1
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• pp.11-14
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• 2010

The interaction of -$Al(CH_3)_2$ with -OH on a fully OH-terminated Si (001) surface was studied using density functional theory. Two sites for $Al(CH_3)_3$ to react with the -OH on the surface were identified. The $-Al(CH_3)_2$ product energetically favored the dimer-row site rather than the inter-row site because the Al atom of $-Al(CH_3)_2$ at the dimer-row site was attracted by the lone pair electrons of the O atom in the neighboring -OH. The energy barrier for the transfer of the $-Al(CH_3)_2$ between the two sites was 0.11 eV, and therefore, the $-Al(CH_3)_2$ at the inter-row site can easily transfer to the dimer-row site at room temperature.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.4
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• pp.21-30
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• 2022

To mitigate the environmental impacts of the energy sector, the government of South Korea has made a continuous effort to facilitate the development and commercialization of renewable energy. As a result, the efficiency of renewable energy plants is not a consideration in the potential site selection process. To contribute to the overall sustainability of this increasingly important sector, this study utilizes the Black-Scholes model to evaluate the economic value of potential sites for off-site wind farms, while analyzing the environmental mitigation of these potential sites in terms of carbon emission reduction. In order to incorporate the importance of flexibility and uncertainty factors in the evaluation process, this study has developed a site evaluation model focused on system dynamics and real option approaches that compares the expected revenue and expected cost during the life cycle of off-site wind farm sites. Using sensitivity analysis, this study further investigates two uncertainty factors (namely, investment cost and wind energy production) on the economic value and carbon emission reduction of potential wind farm locations.

• Advances in Computational Design
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• v.7 no.4
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• pp.345-369
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• 2022

Infectious disease emergency hospitals are usually temporarily built during the pneumonia epidemic with higher requirements regarding diagnosis and treatment efficiency, hygiene and safety, and infection control.This study aims to identify how the Building Information Modeling (BIM) + Industrialized Building System (IBS) approach could rapidly deliver an infectious disease hospital and develop site epidemic spreading algorithms. Coronavirus-19 pneumonia construction site spreading algorithm model mind map and block diagram of the construction site epidemic spreading algorithm model were developed. BIM+IBS approach could maximize the repetition of reinforced components and reduce the number of particular components. Huoshenshan Hospital adopted IBS and BIM in the construction, which reduced the workload of on-site operations and avoided later rectification. BIM+IBS integrated information on building materials, building planning, building participants, and construction machinery, and realized construction visualization control and parametric design. The delivery of Huoshenshan Hospital was during the most critical period of the Coronavirus-19 pneumonia epidemic. The development of a construction site epidemic spreading algorithm provided theoretical and numerical support for prevention. The agent-based analysis on hospital evacuation observed "arched" congestion formed at the evacuation exit, indicating behavioral blindness caused by fear in emergencies.

• Korean Journal of Construction Engineering and Management
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• v.15 no.6
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• pp.71-82
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• 2014

Korea's labor productivity in construction sites is dependent on experience and act in accordance with the human element of the construction workers. In order to increase the work productivity of the construction site that requires a strategic management to potentially hindrance factors of labor productivity. However, without considering the potential problems, management of labor productivity in prior studies is focused only on the immediate problems. The purpose of this study is to compare the site-specific analysis of labor productivity impediments using easy IPA to identify potential causes. As a result of the analysis was to identify the realistic problems of job insecurity and poor working conditions as well as economic problems. It is expected that it is possible to provide the basic data to strategy suggestions for long-term labor productivity improvement of the construction site.

• Environmental Engineering Research
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• v.7 no.2
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• pp.59-66
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• 2002

• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.319-326
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• 2018

Since the Fukushima Daiichi nuclear disaster, concern and worry about multiunit accidents have been increasing. Korea has a higher urgency to evaluate its site risk because its number of nuclear power plants (NPPs) and population density are higher than those in other countries. Since the 1980s, technical documents have been published on multiunit probabilistic safety assessment (PSA), but the Fukushima accident accelerated research on multiunit PSA. It is therefore necessary to summarize the present situation and draw implications for further research. This article reviews journal and conference papers on multiunit or site risk evaluation published between 2011 and 2016. The contents of the reviewed literature are classified as research status, initiators, and methodologies representing dependencies, and the insights and conclusions are consolidated. As of 2017, the regulatory authority and nuclear power utility have launched a full-scale project to assess multiunit risk in Korea. This article provides comprehensive reference materials on the necessary enabling technology for subsequent studies of multiunit or site risk assessment.

• International conference on construction engineering and project management
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• 2024.07a
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• pp.33-40
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• 2024

Off-site construction (OSC) is an architectural approach involving the prefabrication of building structures, components, parts, and equipment in a factory, followed by transportation to the construction site for assembly and installation. This method is particularly suitable for buildings with simple, repetitive structures and straightforward processes, such as hospitals, hotels, and schools. However, the inherent prefabrication characteristic has led to a widespread negative perception among the general public, resulting in significant resistance, especially from parents, concerning educational buildings utilizing OSC. In response, this study targeted users currently employing OSC in institutional buildings to analyze critical perception factors and derive avenues for enhancing the activation of OSC methods. The survey, categorized into seven factors, revealed that safety factors received the most positive responses, while social factors were identified as the most negatively perceived. The analysis of improvement requirements for OSC indicated that addressing issues related to hazardous material exposure and improving air quality are crucial in the equipment and eco-friendly aspects. In terms of design and usability improvement, maintaining harmony with the surrounding environment was identified as essential. Ultimately, this study anticipates the activation of OSC through the analysis of user perceptions and improvement suggestions for each OSC factor.