• 제목/요약/키워드: Bottom structures

검색결과 759건 처리시간 0.031초

원추형 하단부 구조를 갖는 캡슐의 하나로와의 양립성시험 (Compatibility Test of the Capsule with Cone Shape Bottom Guide Structures to the HANARO Reactor)

  • 최명환;조만순;주기남;박승재;김봉구;강영환
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.444-449
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    • 2004
  • The design modification of bottom guide structures of the instrumented capsule, which is used for the irradiation test in the HANARO reactor, was required because of the trouble of the bottom guide arm's pin during irradiation. The previous structure with 3-pin arms was changed into the cone shape of one body. The specimens of the bottom end cap ring with three different sizes (${\Phi}68/70/72mm$) were designed and manufactured. The out-pile tests for the capsule with previous and new three bottom guide structures were performed in the one-channel flow test facilities. In order to evaluate the compatibility with HANARO and the structural integrity of the capsule, a loading/unloading, a pressure drop, a thermal performance, a vibration, and an endurance test were conducted. From out-pile test results, the capsule with the cone shape bottom guide structures was found to be more stable than the previous structure and the optimized size of the bottom guide structure selected was 70mm in diameter. It is expected that the new bottom guide structures will be applicable to all material and special capsules which will be designed and manufactured for the irradiation tests in the future.

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지반과 구조물 사이의 상호작용을 고려한 농업용 사이로의 해석에 관한 연구(IV) -제 4 보 관행설계법과의 비교 (An Analysis of the Farm Silo Supported by Ground)

  • 조진구;조현영
    • 한국농공학회지
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    • 제30권2호
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    • pp.44-54
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    • 1988
  • This study was carried out to investigate the applicability of the conventional design method for ground supported circular cylindrical shell structures. For this purpose, the ensiled farm silo was adopted as a model structures. Herein, the conventional design method was based on the assumption that such structures are clamped at the bottom edges or the ground pressure is independent of the deflection at the surface. In the present paper, the applicability of above assumption was checked out by comparison with an exact method considering soil-structure interaction. Some results of numerical calculation show us ; When the ground is very hard, for example Winkler's constant k is larger than 100 kg / cm$^2$ / cm, or the bottom plate of structures has a infinitely stiffness, for example the bottom plate thickness is larger than 100 cm, the sectional forces, obtained from the conventional method at any wall of structures resting on an elastic foundation, can used for design purpose. Therefore, if the above condition is satisfied then the conventional assumptions can be justified for the design purpose. In this case, the assumption that such structures are fixed at the lower edges was more realistic than the assumption that the reaction pressure acting on structures is uniformly disributed since the accuracy of results of the analysis by the former assumption was higher than that obtained from the latter assumption. But the sectional forces in the bottom plate resting on ground directly could not be evaluate correctly by the conventional method.

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Bottom 컬렉터와 단일 금속층 구조로 설계된 SiGe HBT의 전기적 특성 (Electrical Properties of SiGe HBTs designed with Bottom Collector and Single Metal Layer Structures)

  • 최아람;최상식;김준식;윤석남;김상훈;심규환
    • 한국전기전자재료학회논문지
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    • 제20권8호
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    • pp.661-665
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    • 2007
  • This paper presents the electrical properties of SiGe HBTs designed with bottom collector and single metal layer structure for RF power amplifier. Base layer was formed with graded-SiGe/Si structures and the collector place to the bottom of the device. Bottom collector and single metal layer structures could significantly simplify the fabrication process. We studied about the influence of SiGe base thickness, number of emitter fingers and temperature dependence $(<200^{\circ}C)$ on electrical properties. The feasible application in $1{\sim}2GHz$ frequency from measured data $BV_{CEO}{\sim}10V,\;f_T{\sim}14GHz,\;{\beta}{\simeq}110,\;NF{\sim}1dB$ using packaged SiGe HBTs. We will discuss the temperature dependent current flow through the e-b, b-c junctions to understand stability and performance of the device.

Study on Applicability of Ultimate Strength Design Formula for Sandwich Panels - Application Cases of Double Hull Tanker Bottom Structures

  • Kim, Bong Ju
    • 한국해양공학회지
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    • 제34권2호
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    • pp.97-109
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    • 2020
  • In this study, ultimate strength characteristics of clamped sandwich panels with metal faces and an elastic isotropic core under combined in-plane compression and lateral pressure loads are investigated to verify the applicability of the ultimate strength design formula for ship structures. Alternative elastomer-cored steel sandwich panels are selected instead of the conventional bottom stiffened panels for a Suezmax-class tanker and then the ultimate strength characteristics of the selected sandwich panels are examined by using nonlinear finite element analysis. The change in the ultimate strength characteristics due to the change in the thickness of the face plate and core as well as the amplitude of lateral pressure are summarized and compared with the results obtained by using the ultimate strength design formula and nonlinear finite element analysis. The insights and conclusions developed in the present study will be useful for the design and development of applications for sandwich panels in double hull tanker structures.

Seismic control of structures using sloped bottom tuned liquid dampers

  • Bhosale, Amardeep D.;Murudi, Mohan M.
    • Structural Engineering and Mechanics
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    • 제64권2호
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    • pp.233-241
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    • 2017
  • Earlier numerous studies have been done on implementation of Tuned Liquid Damper (TLD) for structural vibration control by many researchers. As per current review there is no significant study on a sloped bottom TLD. TLD's are passive devices. A TLD is a tank rigidly attached to the structure and filled partially by liquid. When fundamental linear sloshing frequency is tuned to structure's natural frequency large sloshing amplitude is expected. In this study set of experiments are conducted on flat bottom and sloped bottom TLD at beach slope $20^{\circ}$, $30^{\circ}$ and $45^{\circ}$, for different types of structures, mass ratio, and depth ratio to investigate the overall effectiveness of TLD and specific effect of TLD parameters on structural response. This experimental study shows that a properly designed TLD reduces structural response. It is also observed that effectiveness of TLD increases with increase in mass ratio. In this experimental study an effectiveness of sloped bottom TLD with beach slope $30^{\circ}$ is investigated and compared with that of flat bottom TLD in reducing the structural response. It is observed from this study that efficiency of sloped bottom TLD in reducing the response of structure is more as compared to that of flat bottom TLD. It is shown that there is good agreement between numerical simulation of flat bottom and sloped bottom TLD and its experimental results. Also an attempt has been made to investigate the effectiveness of sloped bottom TLD with beach slope $20^{\circ}$ and $45^{\circ}$.

Bottom ash를 이용한 경량판넬의 특성 연구(2) (A Study on the acoustic characteristic of the Light weight Concrete Pallet using bottom ash)

  • 정갑철;이성호;정진연
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 추계학술대회논문집
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    • pp.384-387
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    • 2006
  • Recently, the method of the apartment building design has been changed from wall type structures to moment structures. With like this reason, dry walls we used plentifully. Especially, the gypsum board was used from previously plentifully however the weak point of it is difficult to maintain because it weak strength. For the improvement of gypsum board, light weight concrete panel using cement board is used recently. As this study is the research of the series t on the development of non-bearing light weight concrete panel using bottom ash, the purpose of this study is to obtain basic data for application in the field. The results are that the structure 1 satisfies domestic standard concerned with sound insulation between households at the laboratory and field test.

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Bottom ash를 이용한 경량판넬의 특성 연구 (A Study on the acoustic characteristic of the Light weight Concrete Panel using bottom ash)

  • 이성호;정갑철;정진연
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.1379-1382
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    • 2006
  • Recently, the method of the apartment building design has been changed from wall type structures to moment structures. With like this reason dry walls are used plentifully. Especially, the gypsum board was used from previously plentifully however the weak point of it is difficult to maintain because it weak strength. For the improvement of gypsum board, light weight concrete panel using cement board is used recently. As this study is the research of the series t on the development of non-hearing light weight concrete Panel using bottom ash, the Purpose of this study is to obtain basic data for application in the field. The results are that the structure 1 satisfies domestic standard concerned with sound insulation between households at the laboratory and field test.

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ZnO-based thin-film transistor inverters using top and bottom gate structures

  • Oh, Min-Suk;Kim, Yong-Hoon;Park, Sung-Kyu;Han, Jeong-In;Lee, Ki-Moon;Im, Seong-Il;Lee, Byoung-H.;Sung, Myung-M.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.461-463
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    • 2009
  • We report on the fabrication of ZnO-based thin-film transistor (TFT) inverters with top and bottom gate structures with $Al_2O_3$ dielectrics grown by atomic layer deposition (ALD). Since the top gate ZnO-based TFT showed somewhat lower field effect mobility than that of the bottom gate device, our ZnO-based TFT inverters were designed with identical dimensions for both channels. This TFT inverter device demonstrated an high voltage gain at a low supply voltage of 5 V and clear dynamic behavior.

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