• 제목/요약/키워드: Change Type

검색결과 6,800건 처리시간 0.039초

산불지역에서 경관유형과 식생구조의 변화 (Changes of Landscape Pattern and Vegetation Structure in Rural Areal Area Disturbed by Fire)

  • 이창석;홍선기
    • The Korean Journal of Ecology
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    • 제21권4호
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    • pp.389-399
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    • 1998
  • this study was focused on the effects of fire on spatial change of vegetation landscape in rural region. Fire types recognized as erown fire, severe surface fire and light surface fire in order of increasing intensity were described in a fire map. GIS was introduced to understand the relationship between fire types and topographic conditions or vegetation types. We also investigated land-use type and regeneration strategies after burning. Fire intensity depended on topographic conditions and vegetation types. Special land-use type in this area was collection of edible mushroom (Tricholoma matsutake). Mushrooms had been obtained from Pinus densiflora forests existing as edaphic climax or managed artificially. Regeneration strategy in burned areas was to make sprouts from burned oak stumps. A higher density and growth rate of sprouts, as compared to those on unburned areas, facilitated vegetation succession from P. densiflora forest to oak forest and consequently led to change of landscape pattern.

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전도성 카본 잉크를 이용한 직류 저항형 습도센서 제작 및 평가 (Evaluation of DC Resistive Humidity Sensors Based on Conductive Carbon Ink)

  • 안태창
    • 센서학회지
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    • 제26권6호
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    • pp.397-401
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    • 2017
  • A DC resistance type humidity sensor using conductive carbon ink was fabricated and its performance was evaluated. The humidity sensor was fabricated using a screen printing technique and have a structure that does not require additional metal electrodes to measure resistance change. To evaluate the performance of the humidity sensor, we measured the DC resistance change under various relative humidity levels. The fabricated humidity sensor showed a resistance change of about $2.5{\sim}50k{\Omega}$ in 11 ~ 95% RH environment. It also shows a linear relationship in the relative humidity versus log DC resistance graph. In comparison with commercial humidity sensor under real environment, it can be confirmed that the resistance of the humidity sensor changes to almost the same level as the measured humidity. These results show that the resistance type humidity sensor can be operated stably in actual environment.

청주 구도심 지역의 가로·가구·필지체계의 형성과 변천 (Formation and Change of Road·Block·Lot System of Old Inner Cheongju City)

  • 원세용;김태영
    • 한국농촌건축학회논문집
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    • 제5권2호
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    • pp.10-19
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    • 2003
  • The purpose of this study was to analyze the formation and change of road-block-lot of the old inner city in cheongju The result of this study are as follows; (I)Among others a system roads of in around the old castle in cheongju city is most of feature north and south direction of road. Lot system is organic relations of north and south direction of road. Therefore, urban tissue in around the old castle in cheongju city is established order road system keep on the change of expansion urban tissue. (2) Block type classified into non-division, 2division and over 3division. (3) The square block remains mostly in Cheongju old castle, two-division block was around south of castle. And block of the grid-form street system divided into over 3 division. Through the guideline about characteristic of block type, residential area should be developed as a characteristics area in the urban area.

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Band engineering of bilayer graphene by metal atoms: First-principles calculations

  • Oh, D.H.;Shin, B.G.;Ahn, J.R.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.267-267
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    • 2010
  • The continuous change in the electronic band structure of metal-adsorbed bilayer graphene was calculated as a function of metal coverage using first-principles calculations. Instead of modifying the unit cell size as a function of metal coverage, the distance between the metal atoms and bilayer graphene in the same $2{\times}2$ unit unit cell was controlled to change the total charges transferred from the metal atoms to bilayer graphene. The validity of the theoretical method was confirmed by reproducing the continuous change in the electronic band structure of K-adsorbed epitaxial bilayer graphene, as shown by Ohta et al. [Science 313, 951 (2006)]. In addition, the changes in the electronic band structures of undoped, n-type, and p-type bilayer graphene were studied schematically as a function of metal coverage using the theoretical method.

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메틸 5-하이드록시 디나프토 [1, 2-2', 3'] 후란-7, 12 디온 6-키복시레이트의 물성 및 변색기전 (Physico-chemical properties and mechanism of color change of methyl 5-hydroxy-dinaphtho [1, 2-2', 3'] furan-7, 12-dione-6-carboxylate)

  • 장혜선;박유미;강경환;우영아;박정일;김박광
    • 약학회지
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    • 제37권2호
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    • pp.198-203
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    • 1993
  • Physico-chemical properties of methyl 5-hydroxy-dinaphtho[1,2-2',3'] furan-7,12-dione-6-carboxylate(MHDDC) were examined. The yellowish color of the solution at pH 8 below changes to a bluish color when the solution is basified to pH 10 above. This color change was presumed to a change of the molecular structure from a quinoid-type to a quinoid-type with the dissociation to the hydroxyl group as shown in chart 1.

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프리캐스트 Girder-Beam 접합부에서 Girder Ledge의 전단내력에 관한 실험적 연구 (An Experimental Study on Shear Strength of Girder Ledge of Precast Girder-Beam Connection)

  • 배준우;박성무
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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    • pp.408-415
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    • 1996
  • This study is aimed to define the behavior of the girder ledge of precast girder-beam joint in rame type precast concrete construction method. The variable of this study is followed : 1) The change of the maximum shear strength depended on the transformation of concrete compressive strength 2) The change of the behavior of ledge depended on the transformation of shear-span ratio 3) The change of maximum shear strength and ductility by the type of reinforcement. The results of this study show the behavior of ledge is affected by shear-span ratio and the maximum shear strength is depended on the concrete compressive strength, reinforcement ratio and effective section area. In addition, through the investigation of the established study, the results of this study suggest the shear friction formula of Raths.

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1945년 이후 한국병원건축 병동부의 변화 (Change of Ward Design in Korean Hospital Architecture since 1945)

  • 유영민
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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    • 제22권4호
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    • pp.67-77
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    • 2016
  • Purpose: This paper aimis to analyze the characteristics of ward plan of Korean hospital architecture constructed in each periods and identify the change since 1945. Methods: Literature review was conducted while ward plans for analysis were sellected. And then the important points of ward design were analyzed in each periods. Results: The important points of ward design - type of corridor in ward plan, number of beds per nursing unit, location of nurse station, organization of multi-bed rooms, location of patient toilet, number of day room, concentration and separation of elevator halls for patient and general- were analyzed and the characteristics of change were identified in each periods. Implications: This paper could be a basic data for arranging the history of hospital architecture in Korea.

상변화 구동 방식 마이크로 펌프의 제작 및 시험 (The Fabrication and Test of a Phase-change Type Micropump)

  • 심우영;이상우;양상식
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제49권6호
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    • pp.360-366
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    • 2000
  • This paper presents the fabrication and test of a micropump consisting of a pair of Al flap valves and a phase-change type actuator. The actuator is composed of a heater, a silicone rubber diaphragm and a working fluid chamber. The diaphragm is actuated by the vaporization and the condensation of the working fluid. The micropump is fabricated by the anisotropic etching, the boron diffusion and the metal evaporation. The forward and the backward flow characteristics of the flap valves illustrate the appropriateness as a check valve. Also, the flow rate of the micropump is measured. When the square wave input voltage of 8 V, 70% duty ratio and 2 Hz is applied to the heater, the maximum flow rate of the micropump is $97\muell/min$ for zero pressure difference.

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탄성 변형을 이용한 동력이 표시되는 감속기 (Speed reducer be indicated a power using of elastic strain)

  • 노수영;남원기;강현국;김남일;김영탁;오세훈
    • 동력기계공학회지
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    • 제10권4호
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    • pp.181-186
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    • 2006
  • In this paper, a noncontact type torque meter using silicone rubber to measure the exact torque value and reduce a vibration and a noise, was developed. When planetary gear speed reducer runs, torque, RPM etc.. of motor change according to load or speed change. So, it needs a device to detect load's change or to diagnose the state of thewhole drive department by monitoring these result values. The noncontact type torque meter using silicone rubber that we're trying to develop this time is low-cost and can measure RPM and torque value simply. Also, it caculate a power using this value and indicate them on screen.

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N-type doping and band gap change of Calix adsorbed on Graphene

  • 박선민;양세나;김기정;김봉수;노광현;이한길
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.341-341
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    • 2010
  • Electronic structure of Calix adsorbed on epitaxial graphene (EG) was investigated using high resolution photoemission spectroscopy (HRPES). Increasing the deposition of calix molecule, we found that EG becomes n-type doping using secondary edge measurement (work function change). As we observe bonding nature of O 1s peak, we found that single O 1s peak can be clearly distinguished in the spectra indicating equivalent adsorption state. Finally, we were able to control the band gap of EG using valence band spectra as we change the amount of calix molecule. In this study, we will propose the possibility of band gap modulation of EG using calix molecule.

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