• Journal of Environmental Impact Assessment
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• v.5 no.1
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• pp.47-60
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• 1996

Nitrate contamination problems from groundwater supplies have been reported throughout many countries in the world, including Korea. Nitrate salts can induce methemoglobinemia and possibly human gastric cancer. To reduce human health risk from nitrate in groundwater supplies, several nitrate risk-management strategies can be developed based on the acceptable level of human health risk, the reasonableness of nitrate-control cost, and the technical feasibility of nitrate-control methods. However, due to a lack of available information, assessing risk, cost and technical feasibility contains elements of uncertainty. In the present paper, a nitrate risk-management methodology using fuzzy sets in combination with a multiobjective decision-making (MODM) technique is developed to assist decision makers in evaluating, with uncertain information, various nitrate risk-management strategies in order to decide a proper strategy.

• Journal of the Korea Institute of Building Construction
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• v.16 no.2
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• pp.141-149
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• 2016

Recently, in an attempt to overcome the defects of quiescent power shutdown system, smart quiescent power control system has been developed. However, due to its higher investment costs, feasibility evaluation must be conducted. While LCCA (Life Cycle Cost Analysis) model is useful to estimate net savings of alternatives that differ with respect to initial costs and operating costs, the environmental burdens are not considered. On the contrary, LCA (Life Cycle Assessment) model is suitable to assess environmental impacts associated with the stages of a product's life but it does not consider costs. In this study, a comprehensive analysis on the economic and environmental impacts of smart quiescent power control system is conducted by using LCCA and LCA model. In addition, sensitivity analysis is carried out to quantify accuracy of estimates.

• Korea Journal of Hospital Management
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• v.23 no.4
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• pp.15-25
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• 2018

Purposes: The objectives of this study present the direction of the criteria for the separately reimbursement of therapeutic medical device. Methodology: We summarized experts' opinion using Delphi survey and Analytic Hierarchy Process(AHP). 48 experts were gathered from Medical Insurance Review Nurses Association, medical device industry, academy and association, Medical Device Expert Evaluation Committee. Descriptive statistics, consistency index, content validity ratio were analyzed. Findings: Clinical utility, patient safety, infection control, cost-homogeneity, cost-effectiveness showed high feasibility and importance, but market contribution and functional utility showed low feasibility and importance in a relative sense. The results of functional utility differed between clinical and non-clinical experts. Measurability was low across the whole area. Among the criteria for the separately reimbursement of therapeutic medical device. Patient safety/infection control and clinical utility showed the highest relative importance values, analyzed using AHP. Practical Implications: Patient safety and infection control are needed to be considered as one of Value Assessment Criteria. It is important to find out how to improve the measurability of therapeutic medical device.

• Journal of Soil and Groundwater Environment
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• v.25 no.4
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• pp.77-86
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• 2020

Persulfate-based advanced oxidation processes (AOPs) can oxidize various organic pollutants. In this study, persulfate/Fe(II) system was utilized in phenol removal, and the effect of various organic and inorganic chelators on Fe(II)-medicated persulfate activation was investigated. The feasibility of persulfate/Fe(II)/chelator in cleanup of phenol-contaminated sediment was confirmed through toxicity assessment. In persulfate/Fe(II) conditions, the rate and extent of phenol removal increased in proportion to persulfate concentration. In chelator injection condition, the rate of phenol removal was inversely proportional to chelator concentration when it was injected above optimum ratio. Thiosulfate showed greater chelation tendency with persulfate than citrate and interfered with persulfate access to Fe(II), making the latter a more suitable chelator for enhancing persulfate activation. In contaminated clay sediment condition, 100% phenol removal was obtained within an hour without chelator, with the removal rate increased up to four times as compared to the rate with chelator addition. A clay sediment toxicity assessment at persulfate:Fe(II):phenol 20:10:1 ratio indicated 71.3% toxicity reduction with 100% phenol removal efficiency. Therefore, persulfate/Fe(II) system demonstrated its potential utility in toxicity reduction and cleanup of organic contaminants in sediments.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.432-439
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• 2009

This research project was carried out to develop the technique to assess quantitatively and rapidly the stability of a tunnel by using the measured displacement at the tunnel construction site under excavation. To achieve this purpose, a critical strain concept was introduced and applied to an assessment of a tunnel under construction. The new technique calculates numerically the strains of the surrounding ground by using the measured displacements during excavation. A numerical practical system was developed based on the proposed analysis technique in this study. The feasibility of the developed analysis module was verified by incorporating the analysis results obtained by commercial programs into the developed analysis module. To verify the feasibility of the developed analysis module, analysis results of models both elastic and elasto-plastic grounds were investigated for the circular tunnel design. Then the measured displacements obtained in the field are utilized practically to assess the safety of tunnels using critical strain concept. It was verified that stress conditions of in-situ ground and ground material properties were accurately assessed by inputting the calculated displacement obtained by commercial program into this module for the elastic ground. However for the elasto-plastic ground, analysis module can reproduce the initial conditions more closely for the soft rock ground than for the weathered soil ground. The stability of tunnels evaluated with two types of strains, that is, the strains obtained by dividing the crown displacement into a tunnel size and the strains obtained by using the analysis module. From this study, it is confirmed that the critical strain concept can be fully adopted within the engineering judgment in practical tunnel problems and the developed module can be used as a reasonable tool for the assessment of the tunnel stability in the field.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.251-259
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• 2023

In this study, as a foundational research aimed at promoting the efficient recycling and environmentally friendly disposal of construction waste through the activation of a selective dismantling system, our primary objective was to analyze the economic feasibility of implementing selective dismantling. To achieve this, we conducted an assessment on a 5-story residential building with a construction area of 2,400 m² as a case study. When considering the additional cost of dismantling construction ① the reduction in waste disposal costs due to decreased mixed waste, ② and the potential revenue from recycling through the separation and sorting of waste materials, and ③ we were able to comprehensively confirm that there is an expected cost-saving effect totaling 34,727,000 KRW when compared to conventional demolition methods.

• Journal of Korea Port Economic Association
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• v.38 no.3
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• pp.69-86
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• 2022

This study analyses the necessity of the large-size shipyard and explores competitiveness factors of it. Furthermore, the competitiveness is evaluated and the economic feasibility of building and operation of shipyard is examined. As a result of AHP analysis of the determining factors of the competitiveness of the repairing shipyard, the importance of the factors was found in the order of arrival and departure safety, repair technology, dock and wharf facilities, repair cost, repair period (on time delivery), and repair parts supply. Moving distance, repair service quality, repair parts supply, arrival and departure safety, repair technology, dock and quay wall facilities, and repair period (on time delivery) were identified as key factors in the AHP analysis for competitiveness of the Busan Port repair shipyard to be built in the future. As a result of the analysing economic feasibility, the net present value of the Busan Port repair shipyard construction and operation investment project was KRW 435.6 billion, and the internal rate of return was 9.8%, higher than the social discount rate (4.5%), and the cost-benefit ratio (B/C) was high at 1.167. As a result of the study, the necessity and economic feasibility of the Busan Port repair shipyard are sufficiently ensured, and the competitiveness assessment was highly positive.

• Fire Science and Engineering
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• v.29 no.5
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• pp.88-95
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• 2015

We propose a weather-related service for fire risk assessment in order to increase fire safety awareness in everyday life. The proposed service offers a fire risk assessment level according to weather forecasts and a degree of fire risk according to fire factors under certain weather conditions. In order to estimate the fire risk, we produced a risk matrix through data mining with a decision tree using investigation data and weather data. Through the proposed service, residents can calculate the degree of fire risk under certain weather conditions using the fire factors around them. In addition, they can choose from various solutions to reduce fire risk. In order to demonstrate the feasibility of the proposed services, we developed a system that offers the services. Whenever weather forecasting is carried out by the Korea Meteorological Administration, the system produces the fire risk assessment levels for seven major cities and nine provinces of South Korea in an online process, as well as the fire risk according to fire factors for the weather conditions in each region.

• Journal of Environmental Impact Assessment
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• v.25 no.2
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• pp.155-164
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• 2016

Soil has been recognized as an important resource due to its finitude and valuable functions. Therefore, many countries have adopted soil quality related indicators in Strategic Environment Impact Assessment(SEIA). However, Korean SEIA has used limited indicators such as soil contamination until now. In this study, the SEIA on "Development Basic Plan" was modified for considering complex characteristics of soil and applied to "Bogeumjari Housing Supply Plan" and "Urban Management Plan". The performance of the SEIA considering soil characteristics was evaluated using a checklist for assessing consistency with upper plan, adequacy of alternatives, and feasibility of siting. Soil organic matter and soil erosion were derived as main indicators for "Basic Development Plans". The proposed SEIA technique equipped with soil indicators is proved to contribute to the soil resource conservation.

• Clean Technology
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• v.16 no.3
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• pp.182-190
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• 2010

The feasibility of clean technology to minimize the $CO_2$ emission by recycling and reuse the waste materials and energy have been studied for the cement industry. A life cycle assessment (LCA) was performed for an alternative raw material-supply method to use the molted slag as the major raw material in the cement clinker manufacturing. Using this new method, a 60% of $CO_2$ could be reduced that comes out during the decarboxylation from the cement rotary kiln. The energy-efficiency improvement and the alternative energy methods that had been determined in our previous study through the environmental assessment of cement industry were applied to the study for the reduction of $CO_2$ emission. The natural gas, one of the fossil fuels, was also used as the first choice to get the result at the earliest time by the most economic and the most efficient green technology and to switch into the carbon neutral energy consumption pattern.