• 제목/요약/키워드: Top-fixed

검색결과 231건 처리시간 0.032초

개흙의 제염에 미치는 볏짚, 석회의 병용효과 (Desalinization of marine soil by the application of straw and lime)

  • 오왕근
    • 한국토양비료학회지
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    • 제24권1호
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    • pp.35-40
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    • 1991
  • 유기물(볏짚)의 병용과 부숙이 탄산석회에 의한 갯흙의 제염에주는 영향을 밝히기 위하여 컬럼시험을 한 결과는 아래와 같다. 1. 볏짚과 탄산석회를 미리 시용하여 부숙시켰을 경우는 투수속도가 빨라졌으나 석고처리에는 미치지 못했으며, 제염(Na) 효과는 $CaCO_3$단용 또는 $CaCO_3$+볏짚분(미부숙)을 따르지 못하였다. 부식된 볏짚에 흡착되어 제염이 늦어진 것으로 판단되었다. 2. Na와 Mg를 치환 침출하기에 충분하지 못한(1/3) $CaCO_4$를 시용했을 경우와 $CaCO_3$만을 시용했을 경우는 표층에 Mg를 집적시키고 그 직하층에서 Mg 를 용탈하여 아랫층에 집적시켰으니, 볏짚분이 병용된 처리에서는 이런 용탈현상없이 물리세탈만이 일어났다. 3. $Na^+$의 제염은 세탈용액의 염농도와 비례하는 것으로 보여서, 상충토가 세탈되여 하충토양용액의 염농도가 높아졌을 경우는 염농도가 높아진 층에서 $Na^+$의 치환제거가 많다. 이 말은 염류의 공급원이 세탈되면 표층토의 Na제염이 부진하다는 것을 의미한다.

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경전철/모노레일의 ATP/ATO를 위한 Tag in-Tag out 설계 (Design of Tag in-Tag out for ATP/ATO in the Light Rail and Monorail)

  • 유등열;이기서;오상민
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 추계학술대회 논문집
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    • pp.1264-1269
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    • 2008
  • We designed a track circuit of Tag in-tag out type that can be used for light rails and monorails. This method is called RFID-Tag and it literally uses RFID-Tag and replaces a fixed track circuit and implements a moving block. The distance between RFID-Tags is set to the length of a train and thus a train is always in contact with one of the tags. A train runs in RFID-Tag in -RFID-Tag out type at all times and the distance between trains can be precisely controlled through the application of a moving block combined with the basic principle of a fixed block, which enables the continuous speed control and enhances the satisfaction of passengers. When constructing a track circuit using RFID-Tag the Tag in-tag out brings us the cost reduction and is more economical than the existing fixed track circuit in that sense and easy for installation and maintenance. The wireless communication between onboard and wayside makes the continuous control possible and can improve the control capacity of ATP/ATO by the implementation of a moving block on top of a fixed one.

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에지 검출을 위한 변형된 top-hat 및 bottom-hat 변환 알고리듬에 관한 연구 (A Modified Top-hat and Bottom-hat transform for Edge Detection)

  • 백운석;이하운
    • 한국전자통신학회논문지
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    • 제11권9호
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    • pp.901-908
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    • 2016
  • 에지는 영상의 가장 기본적인 특징을 나타내며, 에지 검출은 영상처리 분야 및 컴퓨터 비전 영역에서 매우 중요한 역할을 한다. 이러한 에지를 검출하기 위한 연구들이 국내 외적으로 많이 수행되고 있다. 기존의 에지 검출 방법에는 로버츠, 소벨, 프리윗, 라플라시안 등 고정된 값의 마스크를 사용하는 방법들이 있으며 모폴로지 처리 기술 가운데 팽창과 침식을 이용하는 모폴로지 그라디언트 방법 등이 있다. 그러나 이러한 방법들은 대각선 방향이나 완만한 영상의 변화가 있는 경우 에지 검출이 잘 되지 않는 문제가 있다 따라서 본 논문에서는 이러한 경우에도 에지 검출이 잘 되는 변형된 top-hat 및 bottom-hat 변환 방식의 에지 검출 알고리듬을 제안하였다. 제안된 알고리듬을 기존의 방법들과 비교하여 에지 검출 영상을 제시하였으며 코사인 기반의 유사도를 사용하여 성능 및 유사성을 평가하였다.

ZnO 압전박막을 이용한 FBAR의 주파수 응답특성 (Frequency Characteristics of a FBAR using ZnO Thin Film)

  • 도승우;장철영;최현철;이용현
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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    • pp.94-97
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    • 2003
  • This study uses ZnO thin film as a piezoelectric material and Pt as bottom electrode for FBAR (film bulk acoustic resonator) device. ZnO thin film and Pt were deposited by RF-magnetron sputtering method. ZnO thin film and Pt were oriented to c-axis. Top electrode Al was deposited by thermal evaporation. The membrane was formed of bulk micromachining. The FBAR was evaluated by XRD, SEM and electrical characterization. The resonant frequency was measured by HP 8753C Network Analyzer. A fabricated FBAR device exhibited a resonant frequency of 700 MHz ~ 1.5 GHz. When bottom electrode and top electrode thickness were fixed, the resonant frequency was increased as decreasing ZnO thin film thickness.

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RGB LED 배열을 사용하는 역광선 단위의 광학 분석 (Optical Analysis of Backlight Units Using RGB LED Array)

  • 아이시다아웅;이승민;양종경;임연찬;이종찬;박대희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 추계학술대회 논문집
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    • pp.375-376
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    • 2007
  • In this work, we have simulated a 42-inch LED BLU which was based on 300 RGB LEDs. We have done an adjustment of LEDs' strip distance and a height of the top of the LED to the back of the LCD to get white color uniformity. So, we have changed simultaneously the distance between the top of the LEDs and the back of the LCD. Moreover, we set a fixed position for the horizontal of LED's pitch. And then, we have experimented and compared to our simulation data.

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Hybrid-type stretchable interconnects with double-layered liquid metal-on-polyimide serpentine structure

  • Yim, Doo Ri;Park, Chan Woo
    • ETRI Journal
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    • 제44권1호
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    • pp.147-154
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    • 2022
  • We demonstrate a new double-layer structure for stretchable interconnects, where the top surface of a serpentine polyimide support is coated with a thin eutectic gallium-indium liquid metal layer. Because the liquid metal layer is constantly fixed on the solid serpentine body in this liquid-on-solid structure, the overall stretching is accomplished by widening the solid frame itself, with little variation in the total length and cross-sectional area of the current path. Therefore, we can achieve both invariant resistance and infinite fatigue life by combining the stretchable configuration of the underlying body with the freely deformable nature of the top liquid conductor. Further, we fabricated various types of double-layer interconnects as narrow as 10 ㎛ using the roll-painting and lift-off patterning technique based on conventional photolithography and quantitatively validated their beneficial properties. The new interconnecting structure is expected to be widely used in applications requiring high-performance and high-density stretchable circuits owing to its superior reliability and capability to be monolithically integrated with thin-film devices.

링 압축시험에서 마찰인자 구간별 치수 변화의 민감도 (Sensitivity of Dimensional Changes to Interfacial Friction over the Definite Range of Friction Factor in Ring Compression Test)

  • 임중연;노정훈;황병복
    • 소성∙가공
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    • 제19권8호
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    • pp.494-501
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    • 2010
  • The main objective of this study is to examine the sensitivity of calibration curves of FEA of ring compression test to frictional shear factor. Ring compression test has been investigated by measuring dimensional changes at different positions of ring specimen and they include the changes in internal diameter at the middle and top section of the specimen, outer diameter at the middle and top section, surface expansion at the top surface, respectively. Initial ring geometries employed in analysis maintain a fixed ratio of 6 : 3 : 2, i.e. outer diameter : inner diameter : thickness of the ring specimen, which is generally known as 'standard' specimen. A rigid plastic material for different work-hardening characteristics has been modeled for simulations using rigid-plastic finite element code. Analyses have been performed within a definite range of friction as well as over whole range of friction to show different sensitivities to the interfacial friction for different ranges of friction. The results of investigation in this study have been summarized in terms of a dimensionless gradient. It has been known from the results that the dimensional changes at different positions of ring specimen show different linearity and sensitivity to the frictional condition on the contact surface.

연곡사 북부도.동부도 긴급보존처리 및 원형복원 (Restoration and Conservation Treatment about North monk-stupa.East monkstupa in Yeongoksa)

  • 김사덕;신은정;이주완;위광철;양희제
    • 보존과학연구
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    • 통권23호
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    • pp.163-177
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    • 2002
  • North monk-stupa and East monk-stupa , which are placed in Yeongoksa, are delicately sculptured and historically valued so they have been determined as National Treasures. It is assumed that North monk-stupa was made in early Goryeo Dynasty period. Parts of it were damaged by grave robbery in 2001. So restoration was begun in 2001. While restoring it, wrong arrangement on top of the monkstupa was rearranged. Top of East monk-stupa was also arranged in a wrong way so it was restored to its original form. Because each part of top of the monk-stupa was adhered with epoxy resin, it was separated by using thin saw. After being arranged in right order, the middle of monk-stupa was fixed by setting up stainless steel shaft. Anda of North monk-stupa, concerned about being damaged by crack, was adhered with epoxy resin.

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TMD 적용에 따른 Twisted 비정형 건축물의 변위 응답 분석 (Displacement Response Analysis of Twisted Irregular Buildings According to TMD)

  • 유상호;김현수;강주원
    • 한국공간구조학회논문집
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    • 제24권1호
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    • pp.89-98
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    • 2024
  • In this study, we investigated the dynamic characteristics of three irregular building models to analyze the effectiveness of displacement response control with Tuned Mass Damper (TMD) installation in twisted irregular buildings. The three irregular models were developed with a fixed angle of twist per story at one degree, subjected to three historical seismic loads and resonant harmonic loads. By designing TMDs with linear and dashpot attributes, we varied the total mass ratio of the installed TMDs from 0.00625% to 1.0%, encompassing a total of 10 values. Two TMDs were installed at the center of the top story of the analysis model in both X and Y directions to evaluate displacement response control performance based on TMD installation. Our findings suggest that the top displacement response control performance was most effective when a 1.0% TMD was installed at the top layer of the analysis model.

최상층면진시스템을 활용한 고층건물의 진동제어 (Vibration Control of High-rise Building Structures using Top-story Isolation Systems)

  • 김태호;김현수
    • 한국공간구조학회논문집
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    • 제8권5호
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    • pp.75-82
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    • 2008
  • 본 연구에서는 최상층면진시스템을 적용한 고층건물의 진동제어 가능성을 검토하여 보았다. 이를 위하여 20층 및 50층 건물을 예제구조물로 선택하였고 El Centro 남북방향 성분을 지진하중으로 사용하여 수치해석을 수행하였다. 그리고 인공풍하중을 사용하여 풍하중에 대한 예제구조물의 사용성을 검토하였다. 면진되는 상부층의 수를 변화시켜가면서 구조물의 응답을 평가함으로써 최적의 면진질량에 대해서 검토하였다. 또한 상부층면진시스템의 고유진동주기 변화에 따른 진동제어성능의 변화를 고정기초구조물과 비교하여 검토하였다. 해석결과 최상층면진시스템은 동조질량감쇠기로서 활용될 수 있으며 풍하중 및 지진하중에 대한 고층건물의 동적응답을 효과적으로 저감시킬 수 있었다.

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