• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.109-112
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• 2001

A case study of foodwaste treatment was conducted to compare the impacts of four scenarios: incineration, incineration after biogasification, biogasification followed by composting, and composting. Potential contributions to climate change, acidification, consumption of landfill and human toxicity were assessed. Characterization of human toxicity caused by metals and PCDD/DF was performed by three multimedia fate models. Scenarios with a biogasification process showed lower impact on climate change and human toxicity. The ranking of four scenarios on human toxicity varied depending on the characterization models applied. The steady state models placed high priority on emission of heavy metals to farmland, whereas the dynamic model estimated the emission of PCDD/DF from the incineration process as more significant.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1634-1642
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• 2009

본 연구는 자체재질로 복합재 적용한 경우를 기존의 금속구조 차체와 25년 운행기간을 기준으로 환경영향을 비교평가하였다. 본 연구는 알루미늄, 스틸, 하이브리드 복합재, 전체 복합재 인 종 4종의 자체를 고려하였다 네가지 차체 시나리오에 대해 원자재 생산, 차체 제작, 25년 사용 단계, 폐기까지의 환경영향에 대해 LCA 기법을 사용하여 평가하였다. 모든 시나리오 경우, 사용단계가 환경영향 카테고리를 좌우했다. 전제 복합재 시나리오가 매립 또는 소각에 대한 가장 낮은 영향을 주었다. 복합재 차체는 금속자제와 비교해 환경영향 측면에서 30$\sim$50 % 개선효과를 보였다.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.249-265
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• 2006

A life cycle assessment(LCA) is increasing its applicability as a powerful tool for an environmental burdens analysis. In this study, some cases are compared in terms of analysis procedures and results obtained with LCAs for evaluating power generation technologies in Korea. For the comparison, 3 power generation technologies are selected because they produces almost 90% of 2003 total electricity generation in Korea. It is shown that the range of evaluation values amounts to maximally the order of about 105, which is rather large discrepancy than the level of 101 in comparison with foreign studies. The difference seems to be due to the simplicity of modeling used in each case study. It is proposed that this large discrepancy should be obviously clarified to improve their reliability in that electricity is a essentialness for all industries and the capacity of LCA of national-level electricity affects the results of LCA for the other sectors.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1536-1544
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• 2006

The aim of this paper is to show how LCA(Life Cycle Assessment) is used as a tool to evaluate the environmental burdens associated with EMU(Electronic Motor Unit), especially one of main components, an interior panel. Thus, the LCA results are polished into the general environmental product declaration format to communicate with the industrial and institutional customers. The format includes the product information and environmental information. In the list of environmental information, profile is consisted of two major results from the LCA study. One is the inventory analysis and the other is the characterized impact results. The format shown in this paper can be the one of option to choose environmentally preferable product and suggestion aimed at the institutional consumer such as government procurement office and corporation's purchasing department.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.7_spc
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• pp.485-494
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• 2016

The risk-based assessment, also called time-based assessment of structure is usually performed to provide seismic risk evaluation of a target structure for its entire life-cycle, e.g. 50 years. The prediction of collapse probability is the estimator in the risk-based assessment. While the risk-based assessment is the key in the performance-based earthquake engineering, its application is very limited because this evaluation method is very expensive in terms of simulation and computational efforts. So the evaluation database for many archetype structures usually serve as representative of the specific system. However, there is no such an assessment performed for building stocks in Korea. Consequently, the performance objective of current building code, KBC is not clear at least in a quantitative way. This shortcoming gives an unresolved issue to insurance industry, socio-economic impact, seismic safety policy in national and local governments. In this study, we evaluate the comprehensive seismic performance of an low-rise residential buildings with discontinuous structural walls, so called piloti-type structure which is commonly found in low-rise domestic building stocks. The collapse probability is obtained using the risk integral of a conditioned collapse capacity function and regression of current hazard curve. Based on this approach it is expected to provide a robust tool to seismic safety policy as well as seismic risk analysis such as Probable Maximum Loss (PML) commonly used in the insurance industry.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.138-148
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• 2003

In the study, current status of waste plastic recycling was investigated. Some factors to obstruct recycling of waste plastic was analyzed. These factors include the difficulty of obtaining location and man power, unclear marking of recyclable plastic and inefficient rate in producer and consumer deposit system. Life cycle assessment(LCA) study was performed to investigate the environmental impact of waste plastic(PET) recycling. When the recycled raw plastic material is used together with the virgin raw plastic material, all the environmental impact showed (-) value except ozone depletion impact category. The environmental avoided impact was the greatest in the global warming impact category. For active promotion of recycling activity, source separation system of waste plastic should be established first of all. Also, marking system of the recycling waste plastic should be made more clear so that consumers can understand it easily. Other strategies include the determination of decent rate for producer and consumer deposit system, establishment of infrastructure and information system for waste plastic recycling and citizen's cooperation through intensive public education.

• Journal of Construction Engineering and Project Management
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• v.2 no.2
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• pp.53-60
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• 2012

Accurate assessment of $CO_2$ emission from buildings requires gathering $CO_2$ emission data of various construction materials. Unfortunately, the amount of available data is limited in most countries. This study was conducted to present the $CO_2$ emission data of concrete, which is the most important construction material in Korea, by conducting a statistical analysis of the concrete mix proportion. Finally, regression models that can be used to estimate the $CO_2$ emission of concrete in all strengths were developed, and the validity of these models was evaluated using 24 and 35MPa concrete data. The validation test showed that the error ratio of the estimated value did not exceed a maximum of 5.33%. This signifies that the models can be used in acquiring the $CO_2$ emission data of concrete in all strengths. The proposed equations can be used in assessing the environmental impact of various construction structural designs by presenting the $CO_2$ emission data of all concrete types.

• Structural Engineering and Mechanics
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• v.77 no.2
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• pp.197-215
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• 2021

Under a severe environment of multiple hazards such as earthquakes and winds, the life-cycle performance of engineering structures may inevitably be deteriorated due to the fatigue effect caused by long-term exposure to wind loads, which would further increase the structural vulnerability to earthquakes. This paper presents a framework for evaluating the lifetime structural seismic performance under the effect of wind-induced fatigue considering different sources of uncertainties. The seismic behavior of a high-rise steel-concrete composite frame with buckling-restrained braces (FBRB) during its service life is systematically investigated using the proposed approach. Recorded field data for the wind hazard of Fuzhou, Fujian Province of China from Jan. 1, 1980 to Mar. 31, 2019 is collected, based on which the distribution of wind velocity is constructed by the Gumbel model after comparisons. The OpenSees platform is employed to establish the numerical model of the FBRB and conduct subsequent numerical computations. Allowed for the uncertainties caused by the wind generation and structural modeling, the final annual fatigue damage takes the average of 50 groups of simulations. The lifetime structural performance assessments, including static pushover analyses, nonlinear dynamic time history analyses and fragility analyses, are conducted on the time-dependent finite element (FE) models which are modified in lines with the material deterioration models. The results indicate that the structural performance tends to degrade over time under the effect of fatigue, while the influencing degree of fatigue varies with the duration time of fatigue process and seismic intensity. The impact of wind-induced fatigue on structural responses and fragilities are explicitly quantified and discussed in details.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.258-264
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• 2023

The greenhouse gas (GHG) emission assessment of kenaf pellet, produced from locally generated kenaf residues in South Korea, has been studied based on the EU RED-II methodology for calculating GHG impact of biomass fuels. Based on the production pathway of kenaf residue pellet and emission coefficients from EU JRC report, the life cycle GHG emission of kenaf residue pellet is assessed as 3.0 gCO₂eq/MJ_pellet and the life cycle GHG emission of electricity generated from kenaf residue pellet is assessed as 11.9 gCO₂eq/MJ when electrical efficiency of final conversion is 25%. The potential GHG emission reduction of electricity produced from kenaf pellet is 90.3% compared to the domestic electricity emission factor 42.8 kgCO₂eq/MWh. Also, the electricity produced from kenaf pellet can reduce at least 59.6% of GHG emission compared to the electricity produced from imported wood pellets.

• Korean Journal of Construction Engineering and Management
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• v.19 no.6
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• pp.46-54
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• 2018

In the 21st century, the Earth has continued its efforts to reduce carbon emissions to overcome the crisis caused by climate change. The construction industry, which is a representative industry that produces large amounts of the environmental load during construction, should actively reduce the amount of the environmental load. From the planning stage of the construction facility, it is necessary to consider the environmental load such as route selection and structure type selection to reduce the environmental load. However, the environmental load can be estimated based on the input resource amount. However, in the planning stage, it is difficult to accurately calculate the environmental load due to lack of information on the construction amount. The purpose of this study is to select the environmental load factors for IPC girder bridges to be used in the environmental load estimation model in the planning stage. Specific information related to the environmental load was selected from a list of information available in the planning stage, reflecting the Life Cycle Assessment(LCA), correlation, principal components analysis and expert opinion. The list of selected planning stage information is 10 such as span length and bridge extension, and it is expected to be used as a basic data for the future development of environmental load estimation model.