• 제목/요약/키워드: Rearrangement

검색결과 813건 처리시간 0.031초

Synthesis of Novel Mercaptophenyl Carbocyclic C-Nucleoside Analogue Using Sequential [3,3]-Sigmatropic Rearrangement and Ring-closing Metathesis

  • Li, Hua;Hong, Joon-Hee
    • Bulletin of the Korean Chemical Society
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    • 제29권4호
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    • pp.847-850
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    • 2008
  • Novel mercaptophenyl carbocyclic C-nucleoside analogue was synthesized via a cyclopentenol intermediate 10, which was prepared using a sequential [3,3]-sigmatropic rearrangement and ring-closing metathesis (RCM). Friedel-Crafts alkylation was then used to couple the thiophenol.

특허 포트폴리오 구성과 신제품 출시 성과: 특허 재정비 활동의 조절효과를 중심으로 (Patent Portfolio Composition and New Product Introduction: The Moderating Role of Technological Resource Rearrangement)

  • 김나미;이종선
    • 지식경영연구
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    • 제19권3호
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    • pp.63-87
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    • 2018
  • In a rapidly changing technology environment, managing and rearranging the patent portfolios is one of the main sources of competitive advantage for firms. This study analyzes the effects of patent portfolio composition on new product introduction related to resource allocation. This study also looks at the moderating role of rearranging the patent portfolios on new product introduction. Our empirical analysis of the global pharmaceutical industry shows that firms with high-value patent portfolios exhibit a tendency to launch new products, and patent portfolio diversity shows a U-shaped relationship with new product introduction. In addition, the patent portfolio rearrangement positively moderates the relationship between patent portfolio diversity and new product introduction. The results are expected to provide implications for firms' patent portfolio composition and patent portfolio rearrangement related to innovation performance such as new product introduction.

알루미나-활석계의 액상소결에서 알루미나 입자크기가 치밀화 거동에 미치는 영향 (Effects of Particle Size of Alumina on Densification Behaviors of Alumina-Talc System During Liquid-Phase Sintering)

  • 김호양;이정아;김정주
    • 한국세라믹학회지
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    • 제35권12호
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    • pp.1308-1315
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    • 1998
  • Effects of particle size of alumina on densification behavior during liquid-phase sintering of alumina-talc system were investigated with emphasis on particle rearrangement process. In the case of using coarse alu-mina powder densiication of specimens was rapidly accelerated after formation of liquid phase due to easy particle rearrangement process with addition of talc and increase of sintering temperature. On the contrary when fine alumina powder was used premature densification of alumina matrix region formed before for-mation of liquid phase rigid skeleton structure and then it seemed to inhibit rearrangement process during crease of sintering temperature. As results the densification of specimens using coarse alumina powder was higher than that of the case of using fine one.

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해인사 장경판전 주변 건축물 이건에 따른 장경판전 환기 기류 변화 해석 (Numerical Simulation of Ventilation in the Storage Hall of Tripitaka Koreana at Haein Temple in Case of Building Rearrangement)

  • 허남건;이명성;양성진
    • 설비공학논문집
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    • 제19권5호
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    • pp.379-385
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    • 2007
  • In the present study, ventilation flow in the Janggyeongpan-Jeon at Haein temple in case of building rearrangement has been investigated numerically. To achieve more accurate results, detailed shapes such as buildings and the window grills are modeled and tree canopy model is adopted to account for the effect of trees in the computation. Wind velocities as boundary condition are taken from meteorological statistical data. The numerical results show that ventilation flow distributions at Janggyeongpan-Jeon in case of building rearrangement are nearly similar to those before rearrangement.

FINDING EXPLICIT SOLUTIONS FOR LINEAR REGRESSION WITHOUT CORRESPONDENCES BASED ON REARRANGEMENT INEQUALITY

  • MIJIN KIM;HYUNGU LEE;HAYOUNG CHOI
    • Journal of applied mathematics & informatics
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    • 제42권1호
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    • pp.149-158
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    • 2024
  • A least squares problem without correspondences is expressed as the following optimization: Π∈Pminm, x∈ℝn ║Ax-Πy║, where A ∈ ℝm×n and y ∈ ℝm are given. In general, solving such an optimization problem is highly challenging. In this paper we use the rearrangement inequalities to find the closed form of solutions for certain cases. Moreover, despite the stringent constraints, we successfully tackle the nonlinear least squares problem without correspondences by leveraging rearrangement inequalities.

자기 집합 단분자막 개질 금 전극을 이용한 수용액 중 폴리피를 성장에 관한 In-situ EQCM 연구 (In-situ EQCM Study on Growth of Polypyrrole Films Using Gold Electrodes Modified with Self-Assembled Monolayers in an Aqueous Solution)

  • 서경자;전일철
    • 전기화학회지
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    • 제5권3호
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    • pp.143-152
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    • 2002
  • Self-assembled monolayer(SAM)로 변형된 금 전극 위로 폴리피롤의 전기화학적 석출 과정을 수용액 상태에서 in-situ EQCM (Electrochemical Quartz Crystal Microbalance)과 ex-situ AFM (Atomic Force Microscopy)을 이용하여 조사하였다. 금 전극에서 cyclic voltammetry로 살펴본 폴리머의 석출은 산화 제한 전위 (anodic limiting potential) 값에 매우 의존적이었으며 주사 횟수에는 의존하지 않았다. 제한 산화 전위가 0.8V (vs Ag | ArCl) 이상일 때 폴리머의 석출은 크게 증가하였다. 그리고 주사 횟수가 증가하면서 질량의 비이상적 변화가 관찰되었는데 이것은 폴리피롤 필름의 rearrangement가 원인이라고 생각된다. 1-dodecanethiol SAM 전극과 thiophene SAM전극에서는 폴리머가 3차원적으로 성장하며 필름의 rearrangement를 수반하였지만 BPUS $(Bis(\omega(N-pyrrolyl)-n-undecyl)disulfide)$ SAM 전극에서는 2차원적인 layer-by-layer 성장을 하고 필름의 rearrangement는 관찰되지 않았다. 폴리머가 급격하게 전극 면으로 석출되면 사슬 모양과 도너츠 모양의 폴리머를 만들며, 정류 상태에 이르면서 주름잡힌 폴리머 필름이 생성되는 것이 원자 힘 현미경 (Atomic Force Microscopy) 이미지로 관찰되었다.