• 제목/요약/키워드: Branching characteristics

검색결과 131건 처리시간 0.024초

나노구조 단분자막의 전기적 특성 (Electrical Characteristics of Nano-Structural Monolayer)

  • 최용성;조장훈;송진원;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.166-167
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    • 2006
  • Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendrimeric macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and photoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current. Functional photoisometrization organic molecular the photo-stimulus to organic monomolecular L-films and LB films of dendrimer and 8A5H were performed. The 8A5H organic monolayer in case of pressure stimulus occurred that positive course but in case of the photo-stimulus compared positive and negative. It is assumed that generation forms of displacement current were measured when photo-stimulus for Impression.

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국내 자생식물의 유기용매추출물로부터 양파부패균 Penicillium sp. ON-211에 대한 항균활성 검정

  • 하철규;태언희;강선철
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.729-732
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    • 2000
  • 양파의 저온저장중 부패방지를 위한 천연항균제 개발의 일환으로 저장양파로부터 부패세균을 분리한 후 이 균에 대한 식물추출물의 항균활성을 조사하였다. 양파의 저온저장중 과육으로부터 분리한 곰팡이를 MEA와 PDA에서 배양하면서 분생자병과 분생자의 형태적 특성을 조사한 결과 플라스크형의 phialide, 분생자병의 branching type이 simple type이며, conidial head가 columnar shape 가지고 있는 것으로 확인되어 Penicillium sp. ON-211으로 동정하였다. 또한 자생 식물은 채집하여 각종 유기용매로 추출한 후 항균활성을 조사하였다. 정향나무, 탱자나무의 잎은 chloroform 분액에서 높은 활성을 나타내었고, 측백나무 열매는 물분획에서 높은 활성을 나타내었으며, 연필향나무의 잎은 ethyl acetate 분획에서 비교적 높은 항균 활성이 나타났다.

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다중모드 무단 변속기의 구조이론에 관한 연구 (Basic Theory on a Multi-Mode CVT)

  • 이진원;장욱진;박진호;박영일;이장무
    • 대한기계학회논문집A
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    • 제24권10호
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    • pp.2477-2486
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    • 2000
  • A planetary gear assembly is a key component to combine and/or split a power from the source. With a planetary gear assembly, a continuously variable unit extends its capacity by means of power bra nching mechanism. Power branching with one planetary gear assembly and one continuously variable unit is categorized into 12 basic types. Each type represents peculiar power transmitting characteristics. Additionally, a multi-mode (range) continuously variable transmission can be designed with accompanying clutches. A multi-mode continuously variable transmission changes the path through which the source power is transmitted. Each path has its own features, such as high efficiency. In this paper, some design principles are examined such as, criteria to guarantee the minimum power efficiency, and constraints to guarantee the smooth mode shift after discussing well-known features of multi-mode M mathematically.

Modification of amylose content of sweetpotato starch by RNAi technique

  • Shimada, Takiko;Otani, Motoyasu;Hamada, Tatsurou;Kim, Sun-Hyung
    • 한국식물생명공학회:학술대회논문집
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    • 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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    • pp.351-355
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    • 2005
  • In the storage roots of sweetpotato (Ipomoea batatas (L.) Lam. cv. Kokei 14), 10 to 20% of starch is essentially unbranched linear amylose and the other major component is branched amylopectin. Amylose is produced by the enzyme GBSSI (granule bound starch synthase I), whereas amylopectin is produced by a concerted action of soluble starch synthase and starch branching enzymes (SBEI and SBEII). We constructed double-stranded RNA (dsRNA) interference vectors of GBSSI and IbSBEII and introduced them into sweetpotato genome via Agrobacterium-mediated gene transformation. The endogenous GBSSI expression was inhibited by dsRNA of GBSSI in 73 % of transgenic plants giving rise to the storage tubers containing amylopectin but not amylose. On the other hand, all sweetpotato plants transformed with dsRNA of IbSBEII contained a larger amount of amylose than the non-transgenic control (up to 25% compared to 10% in the controls). The RNA interference (RNAi) is effectively inhibited the gene expression in thestarch metabolic pathway and modified the characteristics of starch in sweetpotato.

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컴퓨터 그래픽스를 활용한 조경수목 형상자료의 가시화 - AccuRender의 수목 모델링 모듈 활용을 중심으로 - (Visualization of Landscape Tree Forms Using Computer Graphic Techniques: Using the Plant Editing Module in AccuRender)

  • 박시훈;조동범
    • 한국조경학회지
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    • 제27권4호
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    • pp.143-150
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    • 1999
  • The purpose of this research is to find som ways to model tree forms more efficiently in reference with surveying structural data and handling parameters in plant Editor of AccuRender, the AutoCAD-based rendering software adopting the procedural plant modeling technique. In case of modelling a new tree, because it is efficient to modify an existing tree data as a template, we attempted to classify 81 species' data from existing plant library including conifers and deciduous tree. According to the qualitative characteristics and quantitative parameters of geometrical and branching structure, 8 types of tree form were classified with factor and cluster analysis. Some critical aspects found in the distributions of standardized scores of parameters in each type were discussed for explaining the tree forms intuitively. For adaptability of the resulted classification and typical parameters, 10 species of tree were measured and modelled, and proved to be very similar to the real structures of tree forms. CG or CAD-based plant modelling technique would be recommended not only as a presentation tool but for planting design, landscape simulation and assessment.

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나노구조 단분자막의 전기적 특성 연구 (A Study of Electrical Characteristics of Nano-Structural Monolayers)

  • 송진원;신훈규;이경섭;최용성
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제55권12호
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    • pp.586-590
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    • 2006
  • Dendrimers represent a new class of synthetic macromoleculcs characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendrimeric macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and photoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current. Functional photoisometrization organic molecular the photo-stimulus to organic monomolecular L films and LB films of dendrimer and 8A5H were performed. The 8A5H organic monolayer in case of pressure stimulus occurred that positive course but in case of the photo-stimulus compared positive and negative. It is assumed that generation forms of displacement current were measured when photo-stimulus for impression.

나노구조 덴드리머의 변위전류 특성 (Displacement Current Characteristics of Nano-Structural Dendrimer)

  • 송진원;최용성;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.358-359
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    • 2006
  • In the Langmuir-Blodgett (LB) technique, a monolayer on the water surface is transferred onto a substrate, which is raised and dipped through the surface. From this, multilayers can be obtained in which constituent molecules are periodically arranged. The LB technique has attracted considerable interest in the fabrication of electrical and electronic devices. Many researchers have investigated the electrical properties of monolayer and multiplayer films. Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendritic macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and ptoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current.

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Algorithm for Computational Age Dating of Nuclear Material for Nuclear Forensic Purposes

  • Park, Jaechan;Song, Jungho;Ju, Minsu;Chung, Jinyoung;Jeon, Taehoon;Kang, Changwoo;Woo, Seung Min
    • 방사성폐기물학회지
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    • 제20권2호
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    • pp.171-183
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    • 2022
  • The parent and daughter nuclides in a radioactive decay chain arrive at secular equilibrium once they have a large half-life difference. The characteristics of this equilibrium state can be used to estimate the production time of nuclear materials. In this study, a mathematical model and algorithm that can be applied to radio-chronometry using the radioactive equilibrium relationship were investigated, reviewed, and implemented. A Bateman equation that can analyze the decay of radioactive materials over time was used for the mathematical model. To obtain a differential-based solution of the Bateman equation, an algebraic numerical solution approach and two different matrix exponential functions (Moral and Levy) were implemented. The obtained result was compared with those of commonly used algorithms, such as the Chebyshev rational approximation method and WISE Uranium. The experimental analysis confirmed the similarity of the results. However, the Moral method led to an increasing calculation uncertainty once there was a branching decay, so this aspect must be improved. The time period corresponding to the production of nuclear materials or nuclear activity can be estimated using the proposed algorithm when uranium or its daughter nuclides are included in the target materials for nuclear forensics.

Rhizoctonia solani에 의한 큰물개구리밥(Azolla japonica) 마름병 (Rhizoctonia Blight of Azolla japonica Caused by Rhizoctonia solani)

  • 이정한;차재율;노길한;한기수;배동원;권영상;임채신;정성우;권진혁;박정규;곽연식
    • 식물병연구
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    • 제17권3호
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    • pp.405-409
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    • 2011
  • 연 재배연못에서 발견된 큰물개구리밥에 R. solani AHL1에 의해 국지적으로 말라 고사하는 것을 관찰하였다. 병원균을 분리하여 형태적 특징을 조사한 결과 균사는 두께가 $5-6{\mu}m$이고 둔각분지를 하고 있었으며 핵형은 다핵형이었다. 배양적 특성으로 균사생육은 $25^{\circ}C$에서 가장 왕성하였으며 $30^{\circ}C$에서 가장 많은 균핵이 형성되었다. 온도에 따른 병원성과 발병정도를 조사한 결과 $20^{\circ}C$, $25^{\circ}C$$30^{\circ}C$에서 모두 병원성이 나타났으며 발병정도는 $30^{\circ}C$에서 가장 높게 나타났다. 병원균을 유전자 수준에서 동정하기 위해 ITS 영역을 Neighbor-Joining 방법을 이용하여 계통분류분석을 수행한 결과 R. solani로 동정되었다. 본 연구에서 분리된 R. solani AHL1은 벼잎집무늬마름병을 유발하는 병원균과 유사하여 벼에 대한 병 발생 여부는 추가적으로 연구가 필요하다. 현재 농업은 화학비료의 사용을 억제하는 추세로 녹비를 이용한 유기농업으로, 주요 녹비인 Azolla 안정적인 사용을 위하여 Azolla에 발생하는 병에 대한 연구가 더 이루어져야 된다고 사료된다.

질소 분시 비율에 따른 도라지의 생육 및 수량 (Effect of Split Application of Nitrogen Fertilizer on Growth and Yield in Platycodon grandiflorum A. DC.)

  • 성재덕;김금숙;김현태;박충범;김성만
    • 한국약용작물학회지
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    • 제12권6호
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    • pp.437-441
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    • 2004
  • 도라지 재배시 질소 분시 비율이 생육 및 수량에 미치는 영향에 대하여 연구한 도라지 수량 면에서는 2년생 생근과 건근이 50:50 2회 추비 구에서 각각 898 kg, 230 kg으로 가장 많았고, 그 다음이 30:70의 추비 구에서 가장 많았다. 1년차에서의 분시비율은 기비 50%, 추비 50%로 하되, 추비 50%를 2회 나누어 시비하고 2년차는 추비만 시비하는데 이 때 50:50로 2회 나누어 주면 수량 증대에 유리할 것으로 생각된다. 시험결과에서 지상부 생육은 년수 간에는 1년생보다 2년생이 출현기, 개화기가 더 빠르고 경장, 경태가 더 크며 분지수, 엽수도 모두 더 많아 전체적인 생육이 양호하였다. 질소 분시 비율 차이에 따른 지상부 생육은 2년생 근에서는 50:50 2회 추비구가 다른 추비구보다 경태가 굵고, 분지수, 엽수가 많은 경향을 보였다 2년근 지하부 생육은 50:50 2회 추비 구에서 주근장도 가장 길고 지근수도 가장 많아 수량도 건근 230 kg/10a로서 70:30 추비 구 보다 30%의 수량 증대를 보였다. 조사포닌 함량에서도 50:50 추비구가 4.68%로서 가장 높았다. 따라서 도라지 질소 분시 비율은 1년차는 기비 50%와 추비 50%로 하고 2년차는 추비를 50:50 비율로서 2회로 나누어 시비하는 것이 수량과 품질면에서 모두 바람직하며, 특히 2년생 이상을 수확하는 것이 수량면에서 유리할 것으로 보였다.