Optimization of Oil Field Development Plan Using Multiple Local Optima

학위논문 (석사)-- 서울대학교 대학원 : 공과대학 에너지시스템공학부, 2018. 8. 최종근.최대한의 이익을 창출하는 유전개발계획을 세우기 위해서는 주입정과 생산정의 위치, 운영조건, 생산기간 등을 최적화하여야 한다. 이러한 변수들에 대해 최적화 알고리즘을 적용하면 지역최적해에 수렴하여 더 좋은 조건을 가진 유전개발계획을 선택하지 못할 수 있다. 변수들에 대해 광역적으로 탐색한 뒤 얻은 해들을 지역적으로 탐색하면 이 한계를 극복할 수 있다. 광역탐색 알고리즘은 수렴속도는 느리지만 광역적으로 해를 탐색하고, 지역탐색 알고리즘은 수렴속도는 빠르지만 지역최적해에 수렴할 수 있다. 본 연구는 두 알고리즘의 장점, 광역탐색능력과 빠른 수렴속도를 결합하였고 다수의 광역해들에 대해 지역탐색을 수행함으로써 지역최적해에 수렴하는 한계를 보완하였다. 본 연구에서는 광역탐색 알고리즘의 하나인 DE(Differential Evolution) 알고리즘, 지역탐색 알고리즘의 하나인 MADS(Mesh Adaptive Direct Search), 그리고 두 알고리즘을 결합한 제안된 방법의 최적화 결과를 비교하였다. 시뮬레이션 횟수에 따른, 탐색된 순현재가치의 변화와 분포를 비교하여 연구결과를 검증하였다. 제안 방법은 빠르고 안정적으로 최적의 유정위치, 운영조건, 생산기간을 찾으며 지역최적해에서 벗어나 광역최적해를 탐색한다.목 차 제 1 장 서론 01 1.1 연구목적 01 1.2 기존연구 05 제 2 장 이론적 배경 09 2.1 유전개발계획 최적화와 경제성평가 09 2.2 Differential Evolution 알고리즘 11 2.3 Mesh Adaptive Direct Search 알고리즘 15 2.4 DE-MADS-N 20 제 3 장 제안방법의 적용 및 검증 24 3.1 저류층모델 정의 및 최적화 변수 24 3.2 알고리즘 수행결과 비교 33 제 4 장 결론 53 참고문헌 55 Abstract 59Maste

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