• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.479-493
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• 2023

The need for safety management has arisen due to the increasing number of years of operated underground structures, such as tunnels and utility tunnels, and accidents caused by those aging infrastructures. However, in the case of privately managed underground utility ducts, there is a lack of detailed guidelines for facility safety and maintenance, resulting in inadequate safety management. Furthermore, the absence of basic design information and the limited space for safety assessments make applying currently used non-destructive testing methods challenging. Therefore, this study suggests non-destructive inspection methods using ultrasonic and impact-echo techniques to assess the quality of underground structures. Thickness, presence of rebars, depth of rebars, and the presence and depth of internal defects are assessed to provide fundamental data for the safety assessment of box-type general underground structures. To validate the proposed methodology, different conditions of concrete specimens are designed and cured to simulate actual field conditions. Applying ultrasonic and impact signals and collecting data through multi-channel accelerometers determine the thickness of the simulated specimens, the depth of embedded rebar, and the extent of defects. The predicted results are well agreed upon compared with actual measurements. The proposed methodology is expected to contribute to developing safety diagnostic methods applicable to general underground structures in practical field conditions.

• Journal of Environmental Health Sciences
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• v.47 no.1
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• pp.20-35
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• 2021

Objectives: Waste treatment by incineration is gradually increasing as the emission of harmful substances has decreased owing to developments in incineration technology. However, residents living near incinerators continue to express anxiety regarding the effects on their health. Therefore, we attempted to summarize the health impact of incinerators by comprehensively reviewing the recently reported literature. Methods: Sixty-two epidemiological research papers related to incineration and health effects were selected from the Google Scholar database and analyzed (from between January 2001 and December 2019). Results: When compared to older incinerators, newer incinerators established after 2000 are considered relatively safe in terms of health effects. Nevertheless, there have been some studies that have linked them to various diseases, such as malignant tumors including soft tissue cancer and non-Hodgkin's lymphoma, reproductive disorders, respiratory diseases, and more. In addition, incinerator workers and local residents are considered to be exposed to dioxins and some heavy metals from the incinerator. Since most studies included subjects exposed to older incinerators, it is difficult to apply these results to the health impact assessment of new incinerators. However, it is not appropriate to conclude that new incinerators made with state-of-the-art technology are safe, as chronic environmental diseases caused by hazardous substances tend to appear only after prolonged exposure. Conclusions: In terms of environmental health, it is necessary to continuously monitor the health effects of incinerators. Also, there is a need to develop a research methodology that can minimize various confounders in incineration-related epidemiological study.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.259-260
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• 2016

Recently, world-wide focusing on the interest for the reduction of greenhouse gas emissions associated with climate change and global warming, South Korea also has set up a national greenhouse gas reduction target and action plans seeking to achieve them. In particular, in the construction area, to encourage green building certification of the building and carbon labeling acquisition of building products, in order to reduce the environmental impact caused by the industrial activities have been in steady efforts. Therefore, this study estimates the life cycle carbon footprint of building construction materials applied to carbon emissions reduction technology and analyzes the results. Through the CO₂ emissions analysis in construction phase and maintenance phase of the building, it provides basic resource for future research expansion and establishes a step-by-step whole life cycle carbon emissions reduction plan in new construction and existing buildings.

• Journal of Environmental Health Sciences
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• v.44 no.3
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• pp.217-226
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• 2018

Objectives: Despite the positive effects of Off-site risk assessment (ORA) system such as prevention of chemical accidents, some problems have been constantly raised. The purpose of this study is to analyze the problems that have occurred through the implementation of the ORA system for the past three years and to suggest reasonable directions for improvement in the future. Methods: In order to identify the problems with the methodology and procedure of ORA system, we analyzed statutes, administrative rules and documents related to the ORA system. A survey of ORA reviewers in National Institute of Chemical Safety was conducted to investigate the weight of determinants considered when judging the level of total risk in ORA. Results: In this study, we found out the uncertainty of the estimation of the number of people in the impact range in the procedure of the risk assessment of individual handling facilities, the lack of quantitative risk analysis methods for environmental receptors, and the ambiguity of the criteria for the total risk. In addition to suggesting solutions to the problems mentioned above, we also, suggested a decision tree for total risk in ORA. Conclusion: We anticipate that the solutions including the systematic decision tree for total risk suggested will contribute to the smooth operation of the ORA system.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.6
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• pp.722-727
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• 2007

Life Cycle Assessment(LCA) is a tool that quantifies the inputs and outputs, md evaluates the potential environmental impacts during the entire life cycle of a product, material and/or service. Inputs and outputs encompass the consumption of natural resources and emission of pollutants to the environment. One of the deficiencies of the conventional LCA methodology is that it does not consider time explicitly. In addition, there are problems associated with the temporal boundary in the normalization step of LCA. The objective of this study is to propose a new life cycle assessment method that considers time in LCA as called 'Time Load LCA'. Basically Time Load LCA is a method that divides environmental load in each life cycle stage by time duration in each life cycle stage. Time consideration in the proposed method indicated that the new LCA method not only renders new perspective on the environmental impacts of a product system but also rectifies inconsistency in temporal dimension of the normalization step. Basic premise of the time load LCA method is that same amount of load over a shorter time period would affect more seriously on the environment than over a longer time period. therefore, load per time is necessary for the assessment of an impact of the inventory parameters on the environment.

• Structural Engineering and Mechanics
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• v.78 no.3
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• pp.351-368
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• 2021

This paper, by applying a reliability-based framework, develops seismic vulnerability macrozonation maps for Tehran, the capital and one of the most earthquake-vulnerable city of Iran. Seismic performance assessment of 3-, 4- and 5-story steel moment resisting frames (SMRFs), designed according to ASCE/SEI 41-17 and Iranian Code of Practice for Seismic Resistant Design of Buildings (2800 Standard), is investigated in terms of overall maximum inter-story drift ratio (MIDR) and unit repair cost ratio which is hereafter known as "damage ratio". To this end, Tehran city is first meshed into a network of 66 points to numerically locate low- to mid-rise SMRFs. Active faults around Tehran are next modeled explicitly. Two different combination of faults, based on available seismological data, are then developed to explore the impact of choosing a proper seismic scenario. In addition, soil effect is exclusively addressed. After building analytical models, reliability methods in combination with structure-specific probabilistic models are applied to predict demand and damage ratio of structures in a cost-effective paradigm. Due to capability of proposed methodology incorporating both aleatory and epistemic uncertainties explicitly, this framework which is centered on the regional demand and damage ratio estimation via structure-specific characteristics can efficiently pave the way for decision makers to find the most vulnerable area in a regional scale. This technical basis can also be adapted to any other structures which the demand and/or damage ratio prediction models are developed.

• Journal of Environmental Impact Assessment
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• v.8 no.3
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• pp.23-34
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• 1999

The purpose of this research is to establish a green space conservation grade for sustainable urban development of Taegu metropolitan city using GIS and RS methods, together with the valuation items of green spaces centered around ecological, useful, and socio-cultural factors. The results of this study are as follows: 1. According to the ecological factor, the first grade is $81.4km^2$ and then Kachag-myun, Dong-gu in order, have needs of sustaining conservation policy of urban environment improvement and protection of the wild habitats. 2. According to the usefulness of urban parks, the first and second grade which is over 150 $persons/km^2$ in population density of the catchment areas, were Talsung park, Sinam park, Yongsan park and etc., the areas of those parks consists of 0.7% of the whole urban parks. 3. According to the socio-cultural factor, the first grade is located in urban natural parks, and the second grade is which are composed of Green Belt and agriculture in Talsung-gun. 4. Analyzing these results synthetically, the first grade conservation is 18%, as the forest in the upper zone of Mt. Palgongsan, Mt. Bisul, and Mt. Daeduck, these regions needed to preserve absolutely. This research is a basic step to show the methodology for all-round evaluation of green space using GIS and RS. Hereafter, it is necessary to consider general evaluation index of green spaces, and to consider the quantitative and qualitative aspect.

• Journal of Environmental Impact Assessment
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• v.20 no.5
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• pp.585-600
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• 2011

South Korean central government has launched the first comprehensive climate change policies in 1999, and they have been renewed every three year. The third policies ended in 2007. However, it is quite rare to analyze whether the climate change policies are effective against climate change. In this context, this paper aims at analyzing the effectiveness of climate change policy which was launched for seven years from 1999 to 2007 in South Korea. The effectiveness analysis of policy can be done in terms of the individual policy and/or all policies being synthesized as a comprehensive unit. Employing the latter methodology, this paper analyzed the effectiveness on the basis of economic growth as independent variable, greenhouse gas emission as dependent variable, and energy use and its process as intervening variable. Seven analytic indicators covering the three variables were selected on the basis of two points in time before and after climate change policy having been launched. The seven indicators were analyzed in terms of three aspects. They were the change in the state of each indicator, the effectiveness of climate change policy from 1999 to 2007, and the effectiveness process from 1999 to 2007. The effectiveness process was analyzed in terms of the relational context and its flow processing path. Economic growth was advanced remarkably with increase in the total consumption of energy. As a result, greenhouse gas emission increased. However, energy efficiency increased with significant decrease in energy intensity, carbon intensity, and energy elasticity. The expansion of new and renewable energy over total energy supply was not effective significantly on the decrease in greenhouse gas emission. The processing path of climate change policy being effective advanced toward increase in energy efficiency through energy intensity rather than toward sustainable development. Such a way of the effectiveness of climate change policy implies that most policies focused on adaptation rather than on mitigation.

• Journal of Environmental Impact Assessment
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• v.25 no.6
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• pp.402-413
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• 2016

Marine oil spill accidents are occurring continuously due to the marine transportation of the oil. While building a preventive system for oil spill is uttermost necessary, we also need to have a systematic response system to handle the oil spills that inevitably occur. So far, studies have focused on the environmentally sensitive resources affected by oil spills. However, there is a need to conduct research to evaluate the damage to the socially and economically sensitive resources that make up the life of local residents. This study represents the process of building an analytical framework for the assessment of socioeconomic resources affected by marine oil spills. While it is important to provide a scheme for identification and indexation of socially and economically sensitive resources that is compatible with Korea's situations, using existing data for identifying socio-economically sensitive resources might also be meaningful. However, to allow accurate analysis for better evaluation, we need to select more applicable data among the various indicators. In this research, we have reviewed many existing case studies of sensitive resources, studies of the variables that have been used for indexing sensitive resources, and various factors considered in SIA (Social Impact Assessment). Based on the findings, we classify socio-economically sensitive resources into marine products acquisition, population, land usage, administrative area, and cultural heritage and tourist region.

• Journal of Korean Society of Rural Planning
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• v.25 no.3
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• pp.59-66
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• 2019

This study saw developed to build a landscape monitoring methodology by simulation of landscape effect prediction. A Visual landscape planning and management system has been introduced and implemented by each ministry so as to solve the problems of visual landscape destruction due to recognition on the value of natural landscape of beautiful territory and various development projects. At present, this system emphasizes the importance of the visual and perceptual aspect of the landscape however, there is a lack of techniques required for comprehensively predicting, evaluating, and managing it. Furthermore, sustainable landscape management after the completion of development projects has been inadequately carried out, as the focus has been only on consultation in the planning process of the development project in institutional performance. The viewpoint for judging the change in the visual landscape of the development plan and development project should be selected as the effective point where the development project is expected to result in a remarkable landscape change. As for the method of selecting effective viewpoints, the main viewpoints are selected by analyzing the visible area of the target viewpoint. When selecting the viewpoint centered on the viewpoint target, it was judged that it is possible to reduce the procedure of selecting and checking the existing preliminary viewpoints and widening the effective visible range. The proposed visual landscape monitoring is expected to be able to solve the existing institutional problems, and to be used when the implementers and authors of the development projects review the effects on the landscape.