• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.7-14
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• 2008

The main objective of sewer rehabilitation is to improve its function while eliminating inflow/infiltration (I/I). If we can identify the amount of I/I for an individual pipe, it is possible to estimate the I/Is of sub-areas clearly. However, in real, the amount of I/I for an individual pipe is almost impossible to be obtained due to the limitation of cost and time. In this study, I/I occurrence of each sewer pipe is estimated using AHP (Analytic Hierarch Process) and RPDM (Rehabilitation Priority Decision Model for sewer system) was developed using the estimated I/I of each pipe to perform the efficient sewer rehabilitation. Based on the determined amount of I/I for an individual pipe, the RPDM determines the optimal rehabilitation priority (ORP) using a genetic algorithm for sub-areas in term of minimizing the amount of I/I occurring while the rehabilitation process is performed. The benefit obtained by implementing the ORP for rehabilitation of sub-areas is estimated by the only waste water treatment cost (WWTC) of I/I which occurs during the sewer rehabilitation period. The results of the ORP were compared with those of a numerical weighting method (NWM) which is the decision method for the rehabilitation priority in the general sewer rehabilitation practices and the worst order which are other methods to determine the rehabilitation order of sub-areas in field. The ORP reduced the WWTC by 22% compared to the NWM and by 40% compared to the worst order.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1391-1394
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• 2006

노후 상수도관의 개량사업이 지속적으로 시행되고 있지만 노후관 개량사업은 경험적 판단에 의존하는 노후관 평가 및 대안의 선정, 사고예방을 위한 대응적 차원의 개량 사업을 실시함으로 인해 경제적 손실은 물론 시스템의 유기적 기능향상이 이루어지지 않고 있는 실정이다. 이에 본 연구에서는 상수관로 중에서 아연도 강관, 도복장 강관, 닥타일 주철관을 선정하여 현장조사를 실시하였으며, 직접 채취된 관체 시편을 대상으로 육안분석, 관체분석, 그리고 토양부식성 등을 평가하여 채취한 관의 노후도를 종합적으로 평가하였다. 기본적으로 노후도 평가를 점수 평가법을 사용하였으며, 평가된 결과를 바탕으로 향후 노후 수도관 개량사업 추진 내용에서 개대체 우선순위를 결정하기 위한 모델을 제안하였다. 상수관로 노후도 영향 인자 및 가중치 추정은 현재 매설된 상수관로의 노후진척도를 평가하기 위한 노후도 예측모형의 기본 요소이며, 모형의 정확도를 향상시키기 위해 필수적인 사항이다. 관로 노후진척도 분석의 정확도는 장기간의 자료 수집을 통하여 이루어져 이에 대한 분석이 필요하며, 대상관로를 이용하여 개발된 제안식은 향후 지속적으로 현장조사를 실시하여 보완이 필요하겠지만, 노후수도관의 개량 우선순위를 분석하기 위한 매우 유용한 자료가 될 것으로 판단한다.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.5
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• pp.899-908
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• 2021

Since the modern weapon system is composed of a complex system, it is quite difficult to derive the priority of performance improvement factors. In addition, research on the method for prioritizing quantitative performance improvement factors considering the opinions of stakeholders is insufficient. In this study, in order to quantitatively derive the priorities of performance improvement factors for K1 tanks and K2 tanks, a survey was conducted with experts with experience in tank development, and the preface data was analyzed using AHP, scoring method, and TOPSIS methods. As a result, priorities were quantitatively derived. The results of this study are expected to be used as decision-making indicators for stakeholders in the future weapon system development and performance improvement stage.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.171-174
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• 2007

본 논문에서는 다기준 의사결정방법 중에 하나인 AHP(Analytic Hierarchy Process)를 이용하여 상수도관의 개량 우선순위 결정 및 노후화에 영향을 가장 많이 주는 위험요인을 평가할 수 있는 기법을 제안한다. 제안된 방법은 3단계의 계층구조로 구성되어 있으며, 1단계에서는 AHP를 이용하여 우선순위를 예측하고자 하는 관망에 대해서 평가 인자들에 대한 출력값을 산출한다. 2단계에서는 1단계에서 계산된 값들을 이용하여 물리적 척도와 환경적 척도 값을 산출하고, 최종 3단계에서 산출값들을 이용하여 우선순위를 결정하도록 구성되어 있다. 제안된 방법은 FCP에 의한 기존 연구와 비교함으로써 타당성을 검증하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2003.05a
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• pp.481-484
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• 2003

• Journal of Korea Water Resources Association
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• v.44 no.11
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• pp.903-913
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• 2011

In this paper important factors in determining improvement priorities for water pipes were categorized into the effects of a pipe failure to entire pipe network and the characteristics of individual pipe. Subsequently, mathematical models that can quantify these factors were developed using the Fuzzy techniques. The effects of a pipe failure to entire pipe network and the characteristics of individual pipe that were estimated byFuzzy techniques were coined as Fuzzy Importance Index and Fuzzy Characteristic Index, respectively. The Fuzzy Characteristic Index was further categorized into Fuzzy Deterioration Index and Fuzzy Difficulty Index. Considerations were given to applying weights to specific factors in the developed model depending on the circumstances of model applications. To provide an example of the methodology an example pipe network, Net3, of the EPANET program was used. The Fuzzy Importance Index (FII) and Fuzzy Deterioration Index (FDI) were calculated for the Net3 network by considering the hydraulic effects of a pipe failure on the entire pipe network and the pipe deterioration as one of the individual pipe characteristics. Subsequently, the improvement priorities of the pipes in the Net3 pipe network were established based on the FII and FDI.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.635-635
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• 2015

1960년대부터 우리나라는 증가하는 용수수요에 대한 안정적인 생 공용수 공급, 수력발전, 하천생태계 유지를 위한 하천유지용수 공급 및 하천 연안지역의 홍수피해 경감 등의 목적으로 댐 사업이 본격적으로 시작되었다. 그러나 현재 댐 건설적지의 감소, 환경보전에 대한 인식 증대 및 지역 주민의 반대 등으로 신규 댐건설에 한계가 있는 실정이다. 또한 국제적으로 댐 건설 패러다임의 변화로 지속가능한 개발을 위한 노후화된 댐의 개량이 새로운 방안으로 제시됨에 따라 국내에서도 이에 대한 대안으로 기존 댐 재개발의 필요성이 대두되고 있다. 한정된 자원과 인력을 통해 댐 재개발의 효과를 극대화하기 위해서는 댐 재개발 우선순위 결정이 필수적이다. 국내에서도 이에 대한 연구가 진행되어 수자원공사 및 농어촌공사에서 각각 댐 및 농업용 저수지의 재개발 우선순위 평가기법을 제시하였으나 최근 기후변화로 인한 영향이 고려되지 않았을 뿐만 아니라 공공서비스 향상, 고령화율과 안전, 환경 및 지역사회 등 여러 측면을 고려한 기준이 제시되어 있지 않았다. 또한 국내 댐 재개발 우선순위 평가 기술은 다른 선진 국가들에 비해 기술적으로 많이 뒤떨어진 실정이다. 본 연구에서는 국내 댐 재개발 우선순위 평가기준 개발을 위한 국내외 사례조사 및 비교분석을 통해 기존의 댐 재개발 우선순위 결정 기술에서 나아가 기후변화 및 시대적 환경적 측면을 고려한 다 기준 댐 재개발 우선순위를 개발하여 향후 기후변화 적응 댐 재개발 실행프레임워크 구축 기술에 활용하고자 한다.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.183-193
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• 2010

Well planned rehabilitation order of pipes is essential for efficient maintenance and management of Water Distribution Systems. In this study, not only deterioration rate of pipes but also structural and nonstructural failure which causes abnormal condition of WDS is considered to determine rehabilitation order. Probabilistic Neural Network is used for calculating deterioration rate at present and the importance of pipes is computed under structural and nonstructural failure by using Pipe by Pipe Failure Analysis and Effect Index. Utopian Approach, one of the Multi-Criteria Decision Making methods, is used for assessment of final rehabilitation order based on distance measure between utopian point and alternative one. Developed model in this study shows that it gives more reliable results than existing methods considering hydraulic relative importance does in application to real networks. In this point, the newly developed model, which gives advantages over existing models, can make a credible decision and simple application.

• Journal of Korea Water Resources Association
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• v.41 no.2
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• pp.127-135
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• 2008

The objective of sewer rehabilitation is to improve its function while eliminating inflow/infiltration (I/I) and insufficient carrying capacity (ICC). Such rehabilitation efforts, however, have not been particularly successful due to a lack of sewer data and unsystematic field practices. The present study aimed to solve these problems by developing a decision making model consisting of two models: the rehabilitation weighting model (RWM) and the rehabilitation priority model (RPM). In RWM, the I/I of each pipe in a drainage district is estimated according to various defects, with each defect given an individual weighting factor using an analytic hierarchy process (AHP). RPM determines the optimal rehabilitation priority (ORP) using a genetic algorithm (GA). The developed models can be used to overcome the problems associated with unsystematic practices and, in practice, as a decision making tool for urban sewer system rehabilitation.

• Journal of the Korean Society for Railway
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• v.14 no.4
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• pp.354-363
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• 2011

Existing railway bridges have been going through various improvements since the past, with new improvement plans being formed based on social and technological demands. However, there is the need, above all, for an efficient execution plan due to the great number of sites and excessive amount of required expenses contrary to limited assets. The system itself must be held in question in order to systemize various improvement plans, to define and describe factors while utilizing evaluation methods for significance and correlation to achieve generalization. This paper is focused on determining the priority of various improvement plans through the optimization selection process of mutually evaluating alternative plans under various evaluation standards, thus corresponding to the decision-making purpose. The AHP analysis technique was applied for systemization setting and preference evaluation, while the HPT procedure was applied to develop and select appropriate improvement plan factors.