• 풍력에너지저널
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• 제14권3호
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• pp.100-108
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• 2023

The aim of this study is to develop guidelines for predicting interference between drones and wakes during non-destructive blade inspections in wind power systems. The wake generated by wind towers and blades can affect the stability of drone flights, necessitating the establishment of guidelines to ensure safe and efficient inspections. In order to predict the interference between drones and blades, environmental variables must be considered, including quantification of turbulence intensity in the wake generated by the tower and blades, as well as determining the appropriate distance between the drone and the tower/blades for flight stability. To achieve this, computational fluid dynamics (CFD) analysis was performed using cross-sectional geometries corresponding to the main wind turbine blade and tower span locations. Based on the CFD analysis results, a safe flight path for drones is proposed, which minimizes the risk of collision and interference with towers and blades during maintenance operations of wind power systems. Implementation of the proposed guidelines is expected to enhance the safety and efficiency of maintenance work.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.377-380
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• 1996

Most manufacturing systems are large and complex. It is natural to divide the control into a hierarchy consisting of a number fo different levels. Each levels is characterized by the length of the planning horizon and the kind of data required for the decision making process. This paper describes an approach for the incorporation of Maintenance times into a hierachical scheduling for a failure prone flexible manufacturing system. The Maintenance should not be performed too often because of the resulting reduction of capacity. The machine failure and preventive maintenance are considered simultaneously.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.855-858
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• 1988

Two methods for probabilistic maintenance scheduling are developed and compared ; one with operation and supplied-shortage cost and other with risk level of LOLP. Based on the real economic power dispatch, quadratic optimal maintenance conditions are obtained and simple amtrix equations are suggested for solutions. Both methods are compared in a sample system of 26,000 [MW] peak and 32,000 [MW] generation capacity.

• 대한전기학회논문지:전력기술부문A
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• 제53권8호
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• pp.477-483
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• 2004

In competitive electricity markets, maintenance schedule is submitted by generation companies (GENCOs) and transmission companies (TRANSCOs), and coordinated by Independent System Operator (ISO) with the adequacy criterion. This paper presents an alternative coordination procedure by ISO on the maintenance schedule. In this paper, it is focused on modeling a coordination algorithm by ISO for the maintenance schedule based on the Simulated Annealing algorithm. The proposed model employs the minimum information such as generator capacity, forced outage rate and generator maintenance schedules. The objective function of this model represents minimization of adjustment on schedules submitted by GENCOs.

• 한국구조물진단유지관리공학회 논문집
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• 제11권4호
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• pp.147-151
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• 2007

재하시험은 교량의 내하력을 측정하는 효과적인 방법이다. 국내에서 교량의 내하력평가는 계측값과 해석값을 비교하여 산정된 응답보정계수를 사용하여 산정한다. 본 논문에서는 통행차량에 의한 응답보정계수를 결정하는 방법을 개발하였다. 제안된 방법은 차량효과를 고려하기 위하여 컴퓨터 시뮬레이션의 결과에 기반을 두었다. 제안된 방법과 기존 방법의 비교결과는 제안된 방법이 교량의 공용 내하력을 비교적 잘 예측한다는 것을 알 수 있다.

• 한국구조물진단유지관리공학회 논문집
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• 제5권2호
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• pp.121-128
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• 2001

Reinforced concrete frame buildings in regions of low to moderate seismicity are typically designed only for gravity loads with non-seismic detailing provisions of the code. These buildings possess strong beam-weak column, which brings about the brittle structural performance like the column sidesway failure mechanism during the strong lateral load. The objective of this paper is to enhance the column strength and deformation capacity for reconfiguring the structural failure mode by averting a column soft-story collapse and moving to a more ductile beam-sides way mechanism suing new reinforcing materials. Aramid fiber sheet and reinforcing rod-composite materials was used for this purpose. The column was modeled by the 2/3 scale experimental specimen retested. According to the concept of the capacity design, the damaged column was strengthened by the column jacketing using new reinfocing materials such as rod-composite materials. In conclusion, the improvement of the flexural strength is observed and the capacity of the energy dissipation and the ductility is enhanced, too.

• 한국구조물진단유지관리공학회 논문집
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• 제4권4호
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• pp.201-210
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• 2000

The Rehabilitation and repair of structurally deteriorated reinforced concrete structure become more necessary as time goes by. The goal of this study is that provide the data about flexural retrofitted effect of RC beam strengthened by Steel Plate. In order to provide the data, 6 specimens were manufactured and divided with standard specimen and damaged degree A, B, C. Division of damaged A, B, C is based on deflection and degree of crack. In the determination of deflection and degree of crack, we loaded standard specimen to failure under two-point bending to find yielding load and failure load, and then we found deflections and degree of crack that correspond to 75%, 100%, 105% of the yielding load of standard specimen respectively. When we are compared with standard specimen and strengthened specimens, we founded from the experimental results that flexural capacity of structurally damaged beam strengthened by Steel Plate incremented highly, ductility was decreased, and energy absorbtion capacity was almost same.

• 한국구조물진단유지관리공학회 논문집
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• 제19권5호
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• pp.112-119
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• 2015

본 논문에서는 기둥이 취약한 골조의 내진성능을 향상시키기 위한 공법을 제안하였다. 이를 위하여 기둥을 아라미드 시트로 횡구속하여 취성적인 특성을 개선하였으며, S형 스트럿을 가지는 강재 댐퍼를 설치하여 에너지 소산 능력을 증진시켰다. 비보강 실험체 및 보강 실험체를 실물크기로 제작하여 수평하중 저항 능력을 평가하였다. 파괴 양상, 강도, 강성 저하 및 에너지 소산 능력 등에서 보강 실험체의 효과를 확인할 수 있었다. 또한 ABAQUS를 이용한 FE 해석으로부터, 대상 실험체의 이력 거동을 예측 및 평가하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제23권4호
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• pp.53-60
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• 2019

이 연구에서는 정적 변위를 사용하는 유전자 알고리즘을 이용한 교량의 유한요소해석모델 개선 기법을 제안하며, PSC 거더교를 대상으로 한 실증시험 데이터를 이용하여 제안된 방법을 검증하였다. 실증 재하시험으로 정적재하시험과 의사정적재하시험을 수행하였으며, 각 재하시험의 계측 데이터를 이용하여 대상교량의 유한요소해석모델 개선을 진행하였다. 최종적으로 의사정적재하시험의 계측 데이터를 통해 개선된 모델을 이용하여 공용 내하력평가를 수행하였다. 내하력평가에는 현 도로교설계기준과 구 도로교설계기준, AASHTO LRFD의 설계 활하중을 이용하였으며, 각 설계기준 별 내하력평가 결과를 비교하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1848-1852
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• 2008

Maintenance of quality of the compaction is accomplished with the plate load test and density management in roadbed. With the different structure differently the quality of roadbed evaluates indirectly as density and bearing capacity. Control of quality of the compaction very importance but the maintenance of quality is managed still so far with the paper. Recognizes the importance of maintenance of quality from the present paper consequently, and develops a data base one maintenance of quality system with hereafter is expected with the fact that the big help will become in DATA BASE system roadbed plan which is continuous and maintenance of quality.