• 제목/요약/키워드: Combinatorial

검색결과 693건 처리시간 0.035초

Search for Phosphors for Use in Displays and Lightings using Heuristics-based Combinatorial Materials Science

  • Sharma, Asish Kumar;Sohn, Kee-Sun
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.207-210
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    • 2009
  • According to the recent demand for materials for use in various displays and solid state lightings, new phosphors with improved performance have been pursued consistently. Multi objective genetic algorithm assisted combinatorial material search (MOGACMS) strategies have been applied to various multi-compositional inorganic systems to search for new phosphors and to optimize the properties of phosphors.

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Identification of Homoserine Lactone Derivatives Using the Methionine Functionalized Solid Phase Synthesis by Gas Chromatography/Mass Spectrometry

  • Moon, Hong-Sik
    • Archives of Pharmacal Research
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    • 제27권1호
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    • pp.25-30
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    • 2004
  • Combinatorial homoserine lactone mixtures and individual products were obtained from the methionine-functionalized resin in solid-phase synthesis. The four-step process consisting of a coupling step of an N-Fmoc-L-methionine, deprotection of N-Fmoc group, N-coupling with a carboxylic acid, and cleavage reaction through a polymer supported strategy is described. Gas chromatography-mass selective detector (GC-MSD) techniques provide the most powerful methods for identifying both the combinatorial mixtures and individual products.

A Hybrid of Evolutionary Search and Local Heuristic Search for Combinatorial Optimization Problems

  • Park, Lae-Jeong;Park, Cheol-Hoon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제1권1호
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    • pp.6-12
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    • 2001
  • Evolutionary algorithms(EAs) have been successfully applied to many combinatorial optimization problems of various engineering fields. Recently, some comparative studies of EAs with other stochastic search algorithms have, however, shown that they are similar to, or even are not comparable to other heuristic search. In this paper, a new hybrid evolutionary algorithm utilizing a new local heuristic search, for combinatorial optimization problems, is presented. The new intelligent local heuristic search is described, and the behavior of the hybrid search algorithm is investigated on two well-known problems: traveling salesman problems (TSPs), and quadratic assignment problems(QAPs). The results indicate that the proposed hybrid is able to produce solutions of high quality compared with some of evolutionary and simulated annealing.

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Combinatorial Approach Using Caenorhabditis elegans and Mammalian Systems for Aging Research

  • Lee, Gee-Yoon;Sohn, Jooyeon;Lee, Seung-Jae V.
    • Molecules and Cells
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    • 제44권7호
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    • pp.425-432
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    • 2021
  • Aging is associated with functional and structural declines in organisms over time. Organisms as diverse as the nematode Caenorhabditis elegans and mammals share signaling pathways that regulate aging and lifespan. In this review, we discuss recent combinatorial approach to aging research employing C. elegans and mammalian systems that have contributed to our understanding of evolutionarily conserved aging-regulating pathways. The topics covered here include insulin/IGF-1, mechanistic target of rapamycin (mTOR), and sirtuin signaling pathways; dietary restriction; autophagy; mitochondria; and the nervous system. A combinatorial approach employing high-throughput, rapid C. elegans systems, and human model mammalian systems is likely to continue providing mechanistic insights into aging biology and will help develop therapeutics against age-associated disorders.

PRAFFIAN AND YOUNG TABLEAUX

  • Choi, Seul-Hee
    • 대한수학회논문집
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    • 제12권3호
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    • pp.789-796
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    • 1997
  • We consider a Pfaffian and its combinatorial model. We give a bijection between Pfaffian and the generating function of weights of generalized Young tableaux by this combinatorial model, and we find an explicit formula for the Pfaffian by this bijection.

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순열 조합 이해 과제에서의 안구 운동 추적 연구 (Eye Movements in Understanding Combinatorial Problems)

  • 최인용;조한혁
    • 대한수학교육학회지:수학교육학연구
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    • 제26권4호
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    • pp.635-662
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    • 2016
  • 조합(combinatorics)은 확률적 사고의 기초가 되며 정보, 과학 등 타교과와 연계성이 높은 중요한 영역이지만, 학교 수학에서 학생들이 가장 어려워하는 단원 중 하나이다. 본 연구는 순열 조합 문제의 구조를 나타낼 수 있는 표현식을 도입하여, 문제를 표현식으로 변환하는 대학원생의 안구 운동을 분석함으로써 순열 조합 문장제의 이해 과정과 의미 구조에 따른 난이도 차이를 조사하였다. 연구 결과, 연구참여자들의 순열 조합 문장제 이해 전략은 문제에 대한 수학적 모델을 내적으로 직접 표상하는 전략과 보기에 주어진 표현식과 문제를 비교하여 답을 찾는 전략으로 분류할 수 있었다. 전문가 집단인 연구참여자들은 대상들의 구별성, 중복가능성, 의미 구조에 관한 단어나 수치 정보 등 문제의 핵심정보를 빠르게 파악하고 주의를 기울였다. 의미 구조의 변환이 필요한 문제를 풀 때 학생들은 문제의 핵심정보를 더 많이 보고, 보기의 표현식을 더 오래 응시하며, 문제와 보기 사이의 비교를 더 많이 하는 등 복잡한 인지 처리와 연관된 안구운동 지표가 나타났다. 안구 운동 데이터는 문제 이해 과정에서 연구참여자의 수학적 인지를 분석하는데 유의미한 정보를 제공하였다.