• 제목/요약/키워드: Natural interaction

검색결과 1,332건 처리시간 0.027초

Diversity, Interspecific Interaction and Abundance of Undergrowth in Monocultures and Integrated Systems of Natural Rubber Plantation in Danzhou, Southern China

  • Chima, Uzoma Darlington;Qi, Dongling;Wu, Zhixiang;Lan, Guoyu;Chen, Li
    • Journal of Forest and Environmental Science
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    • 제38권2호
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    • pp.75-89
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    • 2022
  • The negative impact of monoculture rubber plantations on biodiversity and associated ecological processes/ecosystem services has led to suggestions on the use of integrated land use systems for rubber cultivation and production in order to ensure environmental sustainability. However, there is paucity of information on the effect of such integrated land use systems on the diversity and abundance of the rubber plantation undergrowth. We evaluated and compared undergrowth plant species composition, richness, abundance, diversity and interaction, in three integrated systems (Rubber-Strelitzia reginae Integrated System - RSrIS, Rubber-Podocarpus nagi Integrated System - RPnIS & Naturally Managed Rubber Plantation - NMRP) with three Rubber Monoculture Plantations (RMP1, RMP2 & RMP3) adjacent to the integrated systems, respectively, at the Investigation and Experiment Station of Tropical Crops, Danzhou, Hainan, China. Undergrowth species density was higher in the rubber monocultures than in the integrated systems except in RSrIS. Species richness and diversity were also higher in the monocultures except in NMRP. Species similarity/interaction between the monocultures and the integrated systems was highest between RMP3 and NMRP. The NRMP proved to be the best model of natural rubber integrated system for the conservation of undergrowth species richness, diversity and interspecific interaction. However, the conservation of undergrowth species in other forms of integrated natural systems can be enhanced by considering the ecology of species to be integrated in terms of their growth characteristics, competitive nature, and ability to grow in association with other species.

능동제어되는 자기부상열차와 교량의 동적상호작용해석 (Dynamic interaction analysis between actively controlled Maglev and bridge)

  • 이준석;권순덕;여인호;김문영
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2008년도 정기 학술대회
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    • pp.555-560
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    • 2008
  • Dynamic interaction analysis between actively controlled Maglev and bridge is carried out. For this, dynamic governing equation for 2-dof Maglev vehicle and optimal feedback control scheme of DOFC are developed. And then the dynamic effect of the 1st natural frequency of bridge, vehicle/bridge mass ratio and damping coefficient of bridge to the both of air-gap variations of UTM-01 maglev vehicle and bridge center maximum displacement response are investigated. From the results of numerical simulation, it is found that the 1st natural frequency of bridge, vehicle/bridge mass ratio and damping coefficient of bridge does not affect greatly within design velocity of the vehicle.

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Wind-induced responses of supertall buildings considering soil-structure interaction

  • Huang, Yajun;Gu, Ming
    • Wind and Structures
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    • 제27권4호
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    • pp.223-234
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    • 2018
  • In this study, a simplified three-dimensional calculation model is developed for the dynamic analysis of soil-pile group-supertall building systems excited by wind loads using the substructure method. Wind loads acting on a 300-m building in different wind directions and terrain conditions are obtained from synchronous pressure measurements conducted in a wind tunnel. The effects of soil-structure interaction (SSI) on the first natural frequency, wind-induced static displacement, root mean square (RMS) of displacement, and RMS of acceleration at the top of supertall buildings are analyzed. The findings demonstrate that with decreasing soil shear wave velocity, the first natural frequency decreases and the static displacement, RMS of displacement and RMS of acceleration increase. In addition, as soil material damping decreases, the RMS of displacement and the RMS of acceleration increase.

해저지반-구조물 상호작용을 고려한 해상풍력발전타워의 진동특성 (A Study on the vibration characteristics of offshore wind turbine tower including seabed soil-structure interaction)

  • 이정탁;이강수;손충렬;박종빈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 춘계학술대회 논문집
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    • pp.416-422
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    • 2009
  • Offshore wind turbine are subjected to more various loads than general land structures and the stability of structures is supported by the piles driven deeply in the subsoil. So it is more important for offshore structures to consider seabed soil-structure interaction than land structures. And the response of a fixed offshore structure supported by pile foundations is affected by resist dynamics lateral loading due to wave forces and ocean environmental loads. In this study, offshore wind tower response are calculated in the time domain using a finite element package(ANSYS 11.0). Several parameters affecting the vibration characteristics of the natural frequency and mode shape and the tower response have been investigated.

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Yeast Two Hybrid Assay를 이용한 Lipocortin-1 결합 단백질 유전자의 분리 (Isolation of the Gene for Lipocortin-1 Binding Protein Using Yeast Two Hybrid Assay)

  • 이경화;김정우
    • 자연과학논문집
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    • 제9권1호
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    • pp.25-29
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    • 1997
  • Glucocorticoid에 의한 항염증 작용의 second messenger로 생각되어지는 annexin superfamily중 하나인 37 kDa의 단백질, lipocortin-1의 작용기작을 이해할 목적으로 in vivo에서 protein-protein interaction을 인식하는 yeast-based genetic assay인 yeast two assay를 통하여 lipocortin-1과 결합하는 단백질 유전자를 분리하여 조사하였다. 이 방법으로 실험을 수행한 결과 분리된 유전자가 human serine proteinase 유전자와 homology가 있는 것으로 밝혀졌다.

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우리나라 사이버 패션에 대한 연구-1994년 이후에 나타난 트랜드 중에서- (Study of Cyber Fashion Concept-After 1994 Fashion Trend-)

  • 이은영;이종련;홍윤택
    • 자연과학논문집
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    • 제11권1호
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    • pp.173-193
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    • 1999
  • 94년 이후의 FASHION TREND는 여러요인의 상호작용으로 제안되어졌다. 이 경향은 과학의 발달로 인한 끊임없는 상상력에 기인하다. 그 중에서도 사이버 패션의 경향은 다음과 같은 현대 복식의 착장미를 보여주고 있다. . 파운데이션의 적용 . 구축적 컷팅 . 양면적인 요소들의 상호작용 등이 많이 표현되어 진다.

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Interaction between IGFBP-5 and TNFR1

  • Kim, Eun-Jung;Jeong, Mi-Suk;Hwang, Jae-Ryoung;Lee, Je-Ho;Jang, Se-Bok
    • Bulletin of the Korean Chemical Society
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    • 제31권7호
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    • pp.2019-2024
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    • 2010
  • Insulin-like growth factor binding protein 5 (IGFBP-5) plays an important role in controlling cell survival, differentiation and apoptosis. Apoptosis can be induced by an extrinsic pathway involving the ligand-mediated activation of death receptors such as tumor necrosis factor receptor 1 (TNFR1). To determine whether IGFBP-5 and TNFR1 interact as members of the same apoptosis pathway, recombinant IGFBP-5 and TNFR1 were isolated. The expression and purification of the full-length TNFR1 and truncated IGFBP-5 proteins were successfully performed in E. coli. The binding of both IGFBP-5 and TNFR1 proteins was detected by surface plasmon resonance spectroscopy (BIAcore), fluorescence measurement, electron microscopy, and size-exclusion column (SEC) chromatography. IGFBP-5 indeed binds to TNFR1 with an apparent $K_D$ of 9 nM. After measuring the fluorescence emission spectra of purified IGFBP-5 and TNFR1, it was found that the tight interaction of these proteins is accompanied by significant conformational changes of one or both. These results indicate that IGFBP-5 acts potently as a novel ligand for TNFR1.

유체력을 고려한 3차원 수중압력선체의 진동특성에 관한 연구 (A Study on the Vibration of Characteristics of 3-Dimension Submerged Vehicle in Consideration of Fluid-Structure Interaction)

  • 손충렬;황인하;이강수
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 춘계학술대회 논문집
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    • pp.81-88
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    • 2000
  • Unlike structures in the air, the vibration analysis of a submerged or floating structure such as offshore structures or ships is possible only when the fluid-structure interaction is understood, as the whole or part of the structure is in contact with water. Specially, the importance of the added mass is not necessary to say like the submerged vehicle, all of the hull body, is positioned in the water. This paper introduce two method to find natural frequency in consideration of fluid-structure modal coupled vibration analysis. The purpose of this study is to analyze of the vibration characteristic of submerged vehicle to obtain the anti-vibration design data, which could be used in the preliminary design stage data. Underwater pressure hull of submerged vehicle is used as the model of this study. The F.E.M model is meshed by shell and beam element. Also, considering of the inner hull weight, mass element is distributed in the direction of hull length. Numerical calculations are accomplished using the commercial B.E.M code. The characteristics of natural frequency(eigenvalues), mode shape(eigenvectors) and frequency-displacement response are analyzed. The results of this study will be used as the useful design data in preliminary anti-vibration design stage.

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