• 한국미생물·생명공학회지
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• 제48권4호
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• pp.423-428
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• 2020

In vitro evolution is a powerful technique for the engineering of yeast strains to study cellular mechanisms associated with evolutionary adaptation; strains with desirable traits for industrial processes can also be generated. There are two distinct approaches to generate evolved strains in vitro: the sequential transfer of cells in the stationary phase into fresh medium or the continuous growth of cells in a chemostat bioreactor via the constant supply of fresh medium. In culture, evolutionary forces drive diverse adaptive mechanisms within the cell to overcome environmental or intracellular stressors. Especially, this engineering strategy has expanded to the field of human cell lines; the understanding of such adaptive mechanisms provides promising targets for the treatment of human genetic diseases and cancer. Therefore, this technology has the potential to generate numerous industrial, medical, and academic applications.

• 한국생산제조학회지
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• 제19권6호
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• pp.826-833
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• 2010

Electric-thermal-structural actuated compliant mechanisms are mechanisms onto which electric voltage drop is applied as input instead of force. This mechanism is based on thermal expansion of material while being heated. Compliant mechanisms are designed subjected to electric charge input using BESO(bi-directional evolutionary structural optimization) method. Reliability-based topology optimization (RBTO) is applied to the topology design of actuators. performance measure approach (PMA), which has probabilistic constraints that are formulated in terms of the reliability index, is adopted to evaluate the probabilistic constraints. In this study, BESO method is used to obtain optimal topology of compliant mechanisms from initial design domain. PMA approach is used to evaluate reliability index. The procedure has been tested in numerical applications and compared with the results obtained by other methods to validate these approaches.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.685-689
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• 2009

진화연산은 최적화와 기계학습에 널리 사용되지만 또한 창조적이고 새로운 것을 만드는 데에도 사용될 수 있다. 본 논문에서는 지식을 표현하는 유연한 구조인 토픽맵에 주목하여, 새롭고 창의적인 토픽맵을 생성하는 토픽맵의 진화 시스템을 제안한다. 여기서는 만들어진 토픽맵이 유효한지에 대한 사람의 평가를 활용하는 대화형 진화 연산 방법(Interactive Evolutionary Computation)이 사용된다. 본 진화하는 토픽맵 시스템은 창의성을 도모하는 도구로서, 사용자들에게 새롭고 창의적인 지식을 떠올릴 수 있도록 도울 수 있을 것이다. 앞으로는 이 시스템에 보다 토픽맵에 정교한 사용자 인터페이스와 시각화 방법을 도입하고 기계학습을 활용하여 시스템의 진화 중에 나타나는 사용자의 피로를 크게 줄이는 방법을 연구할 것이다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.893-896
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• 1998

A new evolutionary programming technique using multiple subpopulations with completely differnt evolution mechanisms is propsed to solve the optimization problems. Three subpopulations, each has different evolution charcteristics and uses different EP algorithms such as SAEP, AEP and FEP, are cooperating with synergy effect in which it increases the possibility to quickly find the global optimum of continuous optimization problems. Subpopulations evolve in differnt manner and the interaction among these leads to global minimum quickly.

• Molecules and Cells
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• 제43권8호
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• pp.728-738
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• 2020

Time and cost-effective production of next-generation sequencing data has enabled the performance of population-scale comparative and evolutionary studies for various species, which are essential for obtaining the comprehensive insight into molecular mechanisms underlying species- or breed-specific traits. In this study, the evolutionary and functional analysis of Korean native pig (KNP) was performed using single nucleotide polymorphism (SNP) data by comparative and population genomic approaches with six different mammalian species and five pig breeds. We examined the evolutionary history of KNP SNPs, and the specific genes of KNP based on the uniqueness of non-synonymous SNPs among the used species and pig breeds. We discovered the evolutionary trajectory of KNP SNPs within the used mammalian species as well as pig breeds. We also found olfaction-associated functions that have been characterized and diversified during evolution, and quantitative trait loci associated with the unique traits of KNP. Our study provides new insight into the evolution of KNP and serves as a good example for a better understanding of domestic animals in terms of evolution and domestication using the combined approaches of comparative and population genomics.

• 한국시뮬레이션학회논문지
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• 제27권2호
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• pp.101-114
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• 2018

무인 비행체의 실시간 경로계획 생성 시 최적의 경로를 찾기 위한 다양한 연구가 진행되어 왔다. 본 논문에서는 진화알고리즘을 통한 무인비행체의 경로계획 생성을 수행하고, 이를 에이전트 기반 시뮬레이션 환경에서 구현 및 테스트가 가능함을 검증하였다. 이를 위해, Repast toolkit에 JGAP 패키지를 탑재하여 Java 기반의 유전 알고리즘 프로그래밍을 통한 무인 비행체의 경로 계획을 생성하였고, 해당 결과를 에이전트 기반으로 시뮬레이션을 수행하였다. 본 논문에서는 에이전트 기반 시뮬레이션 소프트웨어를 소프트웨어 공학 개발 생명주기에 맞춰 문서화하여 설계 및 구현되었으며, 에이전트 모델링 설계는 자동화, 적응성 및 에이전트 간의 상호 작용에 초점을 맞추었다. 또한, 시뮬레이션을 통해 에이전트 기반 환경에서 설계한 모델 및 시나리오를 검증하여 다수의 비행 에이전트에 내재된 동적 경로계획 알고리즘이 실시간으로 자율적인 경로 생성이 가능함을 증명하였다.

• Fisheries and Aquatic Sciences
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• 제20권6호
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• pp.8.1-8.18
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• 2017

Background: Metallothionein (MT) is a multifunctional protein playing important roles in homeostatic regulation and detoxification of metals. Mollusk species have been considered as useful sentinel platforms for MT-based biomarker approaches, and they have been reported to display an extraordinary structural diversity of MT proteins. However, potential diversity of molluskan MTs has not been fully explored and recent updates have suggested the need of revision of evolutionary hypothesis for molluskan MTs. Results: Based on bioinformatic analysis and phylogenetic evidences, novel divergence mechanisms and paths were hypothesized in both gastropod and bivalve MT groups. Our analyses are suggestive of the taxon- or lineage-specific domain multiplication/duplication from the ancestral or prototypic MT. Diversification and selection of molluskan MTs might be driven by the needs for acquiring metal selectiveness, specialized novel function, and improved capacity of metal detoxification under environmentally stressed conditions. Conclusion: The structural diversity and variations of molluskan MTs are significantly larger than previously understood. Undoubtedly, molluskan MTs have undergone dynamic divergent processes in their evolutionary histories, giving rise to the great diversity of domain structures in extant MT isoforms. Novel evolutionary paths for molluskan MTs newly proposed in this review could shed additional light onto the revision of the hypothesis for evolutionary differentiation of MTs in the molluskan lineage.

• 한국지능시스템학회논문지
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• 제8권4호
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• pp.36-42
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• 1998

동적으로 변화하는 환경속에서 적절히 적응하며 행동하는 이동로봇의 제어기를 구성하기는 어렵다. 이를 위하여 진화적 방식을 적용하여 제어기를 구성하고자 하는 연구가 활발히 진행되고 있는데 아직까지는 진화결과 구성된 제어기의 정확한 동작 메커니즘에 대한 분석은 미비한 실정이다. 이 논문에서는 진화결과 구성된 제어기의 동작 메커니즘을 오토메타를 통하여 체계적으로 분석하였다. 그 결과 진화방식은 주어진 문제를 적절히 해결할 수 있는 제어기를 만들어 낼 수 있음을 알 수 있었다. 이때 주어진 문제를 여러 부문제로 세분하고 각 부문제를 해결하는 적절한 메커니즘을 획득하였으며 이러한 메커니즘의 사？작용을 통하여 주어진 전체 문제를 해결하고 있음을 알 수 있었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제18권6호
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• pp.1500-1517
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• 2024

With the rapid development of the tourism economy, large-scale construction of tourist attractions to achieve resource utilization and ensure the healthy development of the tourism industry has become a hot topic. However, there are still issues with resource utilization and coordinated management in the economic development of the tourism industry, which in turn affects the coordinated development of the tourism industry economy. Therefore, this study utilizes self-organization theory to explore the structure, organizational mechanism, conditional driving force of evolution, and evolutionary operation mechanism of the tourism system, analyze the current tourism situation in Hunan Province and related regions, and construct a self-organization evolution model of the tourism system. The result shows that the cumulative variance contribution rate of tourism areas in Hunan Province is 78.8%, with Zhangjiajie having the highest industrial management factors and tourism resource levels in the province, with 1.6 and 3.2 respectively. Hunan Province has abundant tourism resources but overall uneven development, with a comprehensive score of -1.03. Therefore, it is necessary to leverage the coordination advantages of various departments and industries to promote sustainable and healthy development of tourism areas. The self-organizing evolution of the tourism system not only discovers the current problems of the tourism industry, but also provides theoretical support and mechanism suggestions for the tourism system.

• 천문학회보
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• 제40권1호
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• pp.89.2-89.2
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• 2015

This research is to study the effects of individual metal elements(C, N, O, Na, Mg, Al, Si, and Fe) on the standard stellar models. The mixtures of the stellar models have been constructed to analyze the stars, extremely changed in the abundance of these elements. Therefore the mixture are based on the recent observation of stars in globular clusters. And the mass and metallicity grids have been decided in range $0.7{\sim}1.0M_{\odot}$ and 0.0002 ~ 0.007, respectively. The evolutionary tracks and isochrones, as well as the physical changes at each evolutionary phase, have been analyzed. Consequently, we present the mechanisms of the physical changes at each phase, and the quantified effects of the individual elements.