• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.478-481
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• 2010

본 논문에서는 경제학, 사회학, 수학 분야에서 수십년 전부터 연구해오던 죄수의 딜레마 게임의 협동진화에 대해 고찰해보고자 한다. 반복적 죄수의 딜레마 게임은 게임이론의 가장 기본적인 이론으로써, 사회적 상호작용, 경제활동, 국제관계 등 다양한 현상들을 모델링 하기 위한 하나의 방법이다. 그 중에 N명이 참가하는 반복적 죄수 딜레마 게임의 전략은 유전 알고리즘(Genetic Algorithms, GAs)을 통해 진화적으로 만들어 낼 수 있으며, 이 경우에 그 결과를 일반적인 내쉬 균형 이 아닌, 모든 개체들이 유전알고리즘을 통해 협동으로 수렴하도록 유도할 수 있다는 사실은 상당히 시사하는 바가 크다. 기존에 주로 연구되어오던 죄수의 딜레마 게임은 협동으로의 수렴과정에서 일반적으로 순위기반선택(Rank-based selection)과 1점 교배기법(1point crossover)을 사용한다. 그러나 순위기반선택은 모든 개체에 순위을 매겨야 하기 때문에, 개체수가 커질수록 성능이 저하되며, 1점 교배기법은 개체 값이 분산되어있을 경우, 최적해(Optimal solution)을 찾기 힘들다는 단점이 있어, 개체수가 많은 경우에 적용하기에는 비효율적이다. 본 논문에서는 토너먼트 선택기법(Tournament selection)과 자기 적응형 교배기법(Self-adaptive crossover)을 적용한 새로운 기법을 제안한다. 또한 기존 기법과 비교 실험을 통해 제안기법이 기존기법에 비해 평균 수렴시간과 수렴 횟수에서 뛰어난 성능을 보이고 있음을 확인하였다.

• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.139-150
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• 2010

In recent years, more generic drug products became available. The current regulation for assessing the bioequivalence of two drug formulations is based on the concept of average bioequivalence. This approach has been indicated to be insufficient for assessing switchability between two drug formulations and US FDA has adopted individual bioequivalence as one of the bioequivalence criterion since 2001. The US FDA recommends that individual bioequivalence be assessed based on $2\;{\times}\;4$ crossover design, while a $2\;{\times}\;3$ crossover design may be used as an alternative design to reduce the length and cost of the study. In this paper, a statistical procedure for assessment of individual bioequivalence under $3\;{\times}\;2$ crossover designs is proposed and some statistical points are discussed with $2\;{\times}\;3$ crossover design and $2\;{\times}\;3$ extra-reference design through simulation studies.

• 대한예방의학회:학술대회논문집
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• 1999.10a
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• pp.100-101
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• 1999

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.34-34
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• 2003

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05b
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• pp.199-202
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• 2004

DMFC 성능을 개선시키기 위한 연구의 큰 영역은 고분자전해질막에 있으며 methanol crossover에 대한 영향을 최소화시킬 수 있는 소재개발이 우선적으로 요구되는 실정이다. 이러한 문제의 해결을 위해 Pivovar와 Cussler [1] 등은 투과증발 막분리공정에서 메탄올 저항체로 잘 알려진 폴리비닐알콜(poly vinyl alcohol, PVA)를 이용한 전해질막 연구를 하였다.(중략)

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.2
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• pp.103-110
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• 2008

The most failure mode of PEM fuel cell is gas crossover caused by pinhole formation in MEAs. The degradation phenomena of MEA with pinholes were evaluated in various accelerated operation condition, such as OCV, low humidity and high partial pressure of oxygen. The performances of MEA with pinholes were almost same before and after normal 144 hours operation($70^{\circ}C$, $640mA/cm^2$, 65%RH $H_2/air$). The results of accelerated operation showed that OCV and low humidity condition more deteriorated MEA than gas crossover owing to pinholes. When oxygen was used as cathode gas, the pinholes of MEA were enlarged due to heat of combustion reaction on Pt catalyst of electrodes. This combustion reaction occurred at pinholes near gas inlet and resulted in local MEA failure.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.2
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• pp.406-417
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• 2014

This paper presents a numerical optimization method to improve the performance of the propeller with Turbo-Ring using real-coded genetic algorithm. In the presented method, Unimodal Normal Distribution Crossover (UNDX) and Minimal Generation Gap (MGG) model are used as crossover operator and generation-alternation model, respectively. Propeller characteristics are evaluated by a simple surface panel method "SQCM" in the optimization process. Blade sections of the original Turbo-Ring and propeller are replaced by the NACA66 a = 0.8 section. However, original chord, skew, rake and maximum blade thickness distributions in the radial direction are unchanged. Pitch and maximum camber distributions in the radial direction are selected as the design variables. Optimization is conducted to maximize the efficiency of the propeller with Turbo-Ring. The experimental result shows that the efficiency of the optimized propeller with Turbo-Ring is higher than that of the original propeller with Turbo-Ring.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.469-475
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• 2020

During meiosis I, programmed DNA double-strand breaks (DSBs) occur to promote chromosome pairing and recombination between homologs. In Saccharomyces cerevisiae, Mec1 and Tel1, the orthologs of human ATR and ATM, respectively, regulate events upstream of the cell cycle checkpoint to initiate DNA repair. Tel1^ATM and Mec1^ATR are required for phosphorylating various meiotic proteins during recombination. This study aimed to investigate the role of Tel1^ATM and Mec1^ATR in meiotic prophase via physical analysis of recombination. Tel1^ATM cooperated with Mec1^ATR to mediate DSB-to-single end invasion transition, but negatively regulated DSB formation. Furthermore, Mec1^ATR was required for the formation of interhomolog joint molecules from early prophase, thus establishing a recombination partner choice. Moreover, Mec1^ATR specifically promoted crossover-fated DSB repair. Together, these results suggest that Tel1^ATM and Mec1^ATR function redundantly or independently in all post-DSB stages.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.2
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• pp.50-58
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• 1998

Genetic Algorithm (GA) consists of selection, reproduction, crossover and mutation processes and many parameters including population size, generation number, the probability of crossover (Pc) and the probability of mutation (Pm). Determining values of the parameters is found critical in the whole optimization process and a sensitivity analysis with them seems mandatory. This paper tries to demonstrate such importance of sensitivity analysis of GA using an example water supply tunnel network of the New York City. For optimization of the network with GA, Pc and Pm vary from 0.5 to 0.9 by an increment of 0.1 and from 0.01 to 0.05 by an increment of 0.01, respectively, while fixing both the population size and the generation number to 100. This sensitivity analysis results in an optimum design of 22.3879 million dollars at the values of 0.8 and 0.01 for Pc and Pm, respectively. In addition, the probability of recombination (Pr) is introduced to check its applicability in the GA optimization of water distribution network. When Pr is 0.05 with the same values of Pc and Pm as above, the optimum design costs 20.9077 million dollars. This is lower than the cost of 22.3879 million dollars for the case of not using Pr by 6.6%. These results indicate that conducting a sensitivity analysis with parameter values and using Pr are useful in the optimization of WDN.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.165-171
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• 2005

In this paper, the centralized dynamic load-balancing was processed effectively by using the network based parallel genetic algorithm. Unlike the existing method using genetic algorithm, the performance of central scheduler was improved by distributing the process for the searching of the optimal task assignment to clients. A roulette wheel selection and an elite preservation strategy were used as selection operation to improve the convergence speed of optimal solution. A chromosome was encoded by using sliding window method. And a cyclic crossover was used as crossover operation. By the result of simulation for the performance estimation of central scheduler according to the change of flexibility of load-balancing method, it was verified that the performance is improved in the proposed method.