• 환경영향평가
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• 제18권6호
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• pp.367-376
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• 2009

This paper proposes an application methodology of AHP(Analytic Hierarchy Process) based decision making theory for improvement priority by assessment of various risk factors affecting on deterioration of water supply systems, as major social infrastructure. AHP method is organized with three level of hierarchy which is introduced for multi-criteria decision making in this study. In the first level, assessment outputs are calculated by AHP for each affecting factor. In the second level, criteria are estimated by using assessment results with respect to structural and environmental factors. Consequently, ranking decision is performed in the third level. In order to present the effectiveness, a proposed method is compared with FCP(Fuzzy Composite Programming) for decision making. Since the results of the proposed method show better performance with consistent results, it can be applied as an efficient information for the determination for improvement priority of the study infrastructure.

• 품질경영학회지
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• 제47권3호
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• pp.467-478
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• 2019

Purpose: The purpose of this paper is to improve quality for water infiltration to FCISA during military aircraft operation. Methods: A series of troubleshooting studies were conducted to identify the root cause of the water infiltration and reproduce the defects through various simulation tests. And design improvement measures were derived, and countermeasures were taken to prevent recurrence of moisture inflow defects. Conclusion: FCISA operates a very important role in the operation of military aircraft, and defects due to water infiltration are very fatal to flight safety. In this study, the root cause was identified and the design improvement to prevent recurrence was carried out through the failure investigation performed in this study, and the FCISA was improved so that the flight safety was not affected. The results of this study will be valuable back data that can be reflected in the design process through Lessons-Learned in the design phase of the aircraft that will be developed in the future.

• 한국농공학회논문집
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• 제61권2호
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• pp.25-39
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• 2019

The water pollution Accident in the South Han River is increasing due to increase of pollutants inflow from small streams from rural areas and reduced flow rate. This study predicted the change of water quality in the main stream of the South Han River due to climate change through the linkage of watershed and water quality models. Also, This study analyzed the effect of water quality improvement on Seomgang and the South Han River by securing the flow during the dry season. According to the scenarios for securing the river flow during drought season, the river flow in the Seomgang is increased up to 2.19 times, and the water quality during the drought season was improved up to $BOD_5$ 20.5%, T-N 40.8%, T-P 53.4%. Also, the water quality of the main stream of the South Han River improved to 5.22% of $BOD_5$, 5.42% of T-N and 7.69% of T-P as the river flow was secured from the Seomgang. The result of this study confirms that securing the baseflow in the Seomgang according to the scenarios for securing the river flow during the dry season has a positive effect on the improvement of the water quality of the rivers in the main river of the Seomgang and South Han River. The results of this study will contribute to the establishment of reasonable management to improve the water quality of the main stream of the Seomgang and South Han River.

• Environmental Engineering Research
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• 제19권4호
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• pp.309-316
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• 2014

The water quality improvement of golf course ponds, as representative stagnant stream channels, was evaluated by applying a biological activated carbon (BAC) process composed of four consecutive activated carbon reactors. The study was performed from autumn to winter in order to evaluate the feasibility of the BAC process under low temperature conditions. In the study, water quality of pond A (target pond) and pond B (reference pond) were monitored. Pond water was pumped into the BAC process, and was then returned to the pond after treatment. The optimal conditions were determined to be 2 hr of empty bed contact time (EBCT) at a temperature above $4^{\circ}C$, in which improvements of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) of pond A compared to pond B were 3.62%, 3.48% and 1.81%, respectively. On the other hand, as the temperature was below $4^{\circ}C$, some degree of water quality improvement was achieved even when EBCT were 1 or 0.5 hr, suggesting that the BAC process can be successfully applied for the improvement of pond water quality in winter months. The values of biomass concentration and microorganism activity in each condition were highest where 2 hr of EBCT was applied at a temperature above $4^{\circ}C$, but values were similar throughout all treatment conditions, and thus, adsorption is considered to be the dominant factor affecting process efficiency. From the denaturing gel gradient electrophoresis (DGGE) results, no significant differences were observed among the activated carbon reactors, suggesting that the number of reactors in the system could be decreased for a more compact application of the system.

• 대한환경공학회지
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• 제39권10호
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• pp.581-590
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• 2017

석문호 수질을 가장 효율적으로 개선하기 위한 최적의 방안을 마련하기 위해 본 연구에서는 지류하천의 수질 및 유량조사, 퇴적물 조사, 오염원 조사, 하천그룹화를 통한 중점관리 대상유역 선정을 포함한 다양한 분석을 수행하였다. 석문호 유역의 주요 지류하천은 대부분 BOD농도는 낮은 반면 COD농도는 높은 경향을 보였으며, 역천, 당진천, 시곡천, 백석천, 진관소하천, 장항소하천 등은 수질항목에 관계없이 수질농도가 높은 경향을 보였다. 석문호 유역 내 오염원은 생활계, 축산계 및 산업계가 대부분으로 지역에 따라 다양하게 분포하는 것으로 조사되었다. 석문호 수질개선을 위해 중점관리 대상하천으로 선정된 당진천, 역천, 백석천, 장항소하천 유역 내 위치하고 있는 오염원의 우선적인 저감이 필요한 것으로 판단된다. 석문호 수질개선을 위한 다양한 시나리오별 수질개선효과를 수질모델을 이용하여 정량적으로 평가한 결과, 유역 내 오염물질 배출량 관리를 위해 공공하수처리시설을 신설 및 증설만 하여도 호소 수질 V등급을 만족하는 것으로 나타났다.

• 상하수도학회지
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• 제22권5호
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• pp.489-493
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• 2008

• 대한환경공학회지
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• 제31권12호
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• pp.1051-1070
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• 2009

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1182-1183
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1996년도 학술발표회 논문집
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• pp.617-622
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• 1996

• 한국항해항만학회지
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• 제37권4호
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• pp.419-427
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• 2013

본 연구는 수상레저 활성화를 위한 선진국의 관련규제 분석 및 개선 방향을 제시하기 위해 수행되었다. 이러한 연구목적을 달성하기 위해 수상레저 선진국인 미국, 영국, 호주 및 일본의 수상레저 면허 및 교육, 등록 및 검사 그리고 사업에 대한 사례 분석을 실시하였고 국내 수상레저 활동자와 종사자들에게 면허 및 교육, 등록 및 검사 그리고 사업의 애로사항에 대한 인식도를 실증적으로 분석하였으며 다음과 같은 결론을 도출하였다. 첫째, 수상레저 면허제도에 대한 필요성은 '필요하지않다'가 높게 나타났으며 그 이유로는 '교육으로 대체가능'하기 때문이라는 응답이 가장 높았으며 반대로 면허제도가 필요한 이유로는 '수상레저 활동의 안전' 확보로 나타났다. 또한 수상레저 면허 제도의 문제점으로는 '운영제도의 어려움'과 '운영기관의 부족' 등의 순으로 나타났으며 면허제도의 개선방향으로는 '교육기관 및 인력확대', 그리고 '단계별 교육 차별화' 등의 순으로 나타났다. 둘째, 수상레저 등록 및 검사제도의 개선의 필요성에서는 '수상레저기구 등록절차 간소화', '수상레저기구 등록 및 검사기관 확대 필요성' 그리고 '수상레저기구 등록범위 확대 필요성'에 대한 인식도가 높은 것으로 나타났다. 셋째, 종사자들이 인식하는 수상레저사업장의 애로사항으로는 '수상레저기구 입출항 신고 절차의 복잡성', '수상레저사업 신고 및 등록 절차의 복잡성' 그리고 '수상레저 활성화 지원 정책 및 제도 미흡'등의 순으로 나타났다. 결론적으로 국내 수상레저의 활성화를 위해서는 수상레저 활동자들에게는 면허 및 교육제도의 접근성과 편리성을 확보하고 종사자들에게는 수상레저사업의 복잡성을 해결해 줄 수 있는 지원정책의 수립이 지속적으로 이루어져야할 것이다. 즉 수상레저 활동과 사업을 규제하고 있는 수상레저안전법은 수상레저 활동자 및 종사자들의 수요와 요구를 반영할 수 있도록 지속적인 개정 작업이 이루어져야 한다.