36 research outputs found
Enterotoxin 생성 Clostridium perfringens 균주의 한국내 분리와 PCR을 이용한 신속검출법
학위논문(석사)--서울대학교 대학원 :협동과정 농업생물공학과,1998.Maste
Big Bang Cosmology, Quantum Physics, and Origins of Culture - in the light of theories of John Polkinghorne and René Girard -
일반화된 자기 형성 진화 알고리즘의 개발과 제어 문제에 대한 효율적 응용에 대한 연구
널리 쓰이는 진화 알고리즘은 크게 두가지가 있다. 유전 알고리즘과 진화 기법이 그것이다. 이들 알고리즘은 실행 전에 사용자가 정해주어야 하는 변수들을 가지고 있다. 본 논문에서는 이 두 알고리즘을 일반화시키고 집단의 크기, 교차변이 연산자 적용 확률 그리고 돌연변이 연산자 적용 확률과 같은 변수들을 알고리즘이 수행되는 동안 스스로 정하는 일반화된 자기 형성 진화 알고리즘을 제안한다. 제안된 알고리즘의 타당성과 효용성은 시스템 동정화와 다개체 시스템 제어의 두가지 복잡한 제어 문제에 대한 적용을 통해 보여진다
A new hyvrid genetic algorithm and its application to control
학위논문(석사) - 한국과학기술원 : 전기 및 전자공학과, 1994.2, [ iii, 70 p. ]한국과학기술원 : 전기 및 전자공학과
Effects of Mass Media on the Voting Decisions in the National Assembly -Focused on Mutz’s Impersonal Influence
탐색 성능 향상을 위한 감소된 조기 집중 현상을 갖는 하이브리드 유전 알고리즘
학위논문(박사) - 한국과학기술원 : 전기및전자공학과, 1999.2, [ vi, 108 p. ]This thesis deals with the search performance enhancement techniques in genetic algorithms (GAs). Evolutionary algorithms are computational optimization techniques that use simulated evolution. In control area, especially the genetic algorithm has been widely used. Although GAs are good at finding near global optimum quickly, they are poor in the fine tuning of solutions, which may cause `premature convergence``. This thesis is aimed to improve the search performance of GAs with elitist strategy by reducing premature convergence through hybridization or appropriate modification to the algorithms. In order to accomplish the goals, three new genetic algorithms and two new local search operators are proposed. The first method, the modified genetic algorithm (MGA) consists of a fitness modification scheme and adaptive mutation operator. The second method, the adaptive genetic algorithm (AGA) determines crossover and mutation probabilities by itself according to the fitness of a solution to be crossed or mutated. The schema theorem for AGA is derived. The third method, adaptive simulated annealing genetic algorithm (ASAGA) uses simulated annealing-like mutation operator. A novel way of generating a new solution by using a gaussian random number with time-varying variance is proposed and proved to be effective. The first local search operator makes use of neural networks. The second one named SLSO (simple local search operator) uses the difference between the most recent best fitness and a newly found best solution``s fitness, which is computationally simpler than the first one and proved to be powerful. The test problems considered for the performance comparison include the traditional set of test functions, system identification, neural network controller for cart-pole system, evolutionary design of a multi-agents playing a simplified soccer and nonlinear constrained optimization problems. Nine hybrid genetic algorithms are constructed using the proposed algorithms...한국과학기술원 : 전기및전자공학과
