• 제목/요약/키워드: surface humidity

검색결과 904건 처리시간 0.032초

양방향 반사 지연선을 이용한 무선, 무전원 SAW 기반 온, 습도 센서 개발 (Development of a Wireless, Battery-free SAW-based Temperature and Humidity Sensor incorporating a Bidirectional Reflective Delay Line)

  • 임천배;이기근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1515_1516
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    • 2009
  • A 440MHz wireless and passive surface acoustic wave (SAW) based micro-sensor was developed for simultaneous measurement of temperature and humidity. The developed sensor is composed of a SAW reflective delay lines structured by an IDT (Inter-Digital Transducer), four reflectors and humidity sensitive film (polyimide). Polyimide was dry-ecthed by RIE (Reactive Ion Etching) to obtain high roughness, which gives the large reaction area resulting in high sensitivity. In wireless testing using a network analyzer, sharp reflection peaks with high S/N ratio, small signal attenuation, and few spurious peaks were observed in the time domain. High sensitivity towards the temperature and humidiy were also observed in the large concentration range. The obtained sensitivity was $16.8^{\circ}/^{\circ}C$ for temperature sensor and $15.8^{\circ}$/%RH for humidity sensor.

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다공질 실리콘층을 이용한 정전용량형 습도센서의 개발 (Development of Capacitance-type Humidity Sensors Using Porous Silicon Layer)

  • 김성진;이주혁;윤여경;최복길
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.1014-1016
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    • 1998
  • A capacitance-type humidity sensor using porous silicon layer is developed. The unique property of this sensor is a structure which has electrodes on the surface of the wafer like a general IC device. To do this. the sensor was fabricated using process such as localized formation of porous silicon, oxidation of porous silicon layer, and etching of oxidized porous silicon layer. The measurement of humidity-sensing ability was done for two type of sensors using porous silicon layer formed in 25 and 35% HF solutions, respectively. As the result, the former sensors showed larger value and variation of capacitance for the relative humidity.

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미세구조 $TiO_2$계 습도센서의 특성 (Characteristics of Fine Structure $TiO_2$-based Humidity Sensors)

  • 임재영;윤여경;이성필;고성택
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1993년도 춘계학술대회 논문집
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    • pp.129-133
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    • 1993
  • $TiO_2-V_2O_5-Nb_2O_5$ humidity sensors have been fabricated in the ceramic type and their physical and hygroscopic characteristics have been investigated. The additives and sintering conditions affect the humidity sensitivity. XRD patterns, SEM photographs were used for the analysis of crystal structures and surface morphology. $TiO_2-V_2O_5-Nb_2O_5$ humidity sensors had good linearity in the range from 20%RH to 90%RH and the sensitivity of sensor sintered at $1,000^{\circ}C$ for 1hr was 73% at operating temperature $60^{\circ}C$.

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실란 바인더에 따른 탄소나노튜브 박막의 감습 특성 (Response Characteristics of CNT Thin Film on Humidity by Silane Binders)

  • 김성진;이호중
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.196-196
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    • 2010
  • In this work, we deposited SWNTs/silane hybrid thin films by multiple spray-coating on glass substrate, and examined their electrical response for humidity. Generally silane binders which are often used in CNT solution to adhere CNTs to substrate well can be easily functionalized to each own group on the surface of CNTs after they are hardened by way of the hydrolysis reaction. We investigated how silane binders (TEOS,, MTMS and VTMS) in SWNTs hybrid thin films make effect to their electrical response on humidity. As the result, we observed that the resistance in the sample using TEOS was changed dramatically while it was almost invariant in the samples using MTMS and VTMS for increasing humidity.

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철근콘크리트 내부 온습도 경시변화 추정 모델 구축 (Prediction Model for the Change of Temperature and R.H. inside Reinforced Concrete)

  • 박동천
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 추계 학술논문 발표대회
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    • pp.83-84
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    • 2016
  • Surplus water inside a concrete other than moisture that is used for hydration of the cement affects the physical properties of the concrete (modulus of elasticity, compressive strength, drying shrinkage, and creep) by drying. Changes in temperature and humidity inside a concrete has correlation with the movement speed and reaction rate of deterioration factors such as carbon dioxide and chloride ions. In this study, comparison was performed between temperature and relative humidity inside the concrete and meteorological data for exposure environment through measurement at the site for two years. Surface temperature of the concrete (depth 1cm) was measured higher by 6℃ during the summers, while it was measured lower by 2℃ during the winters due to solar radiation, wind, and radiation cooling. As for relative humidity, change was large in the depth of 1cm, while more than 85% was maintained in the depth of 10cm.

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Sol-Gel법에 의한 $TiO_2$ 박막의 제작과 전기적 특성에 관한 연구 (A study on the fabrication and the electrical properties of TiO$_{2}$ thin films by Sol-Gel method)

  • 유도현;강대하;이능현;김진수;이덕출
    • E2M - 전기 전자와 첨단 소재
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    • 제7권4호
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    • pp.325-330
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    • 1994
  • In this paper, $TiO_2$ thin films were fabricated by Sol-Gel method and their electrical conductivity and humidity sensing properties have been investigated. The structure of Sol can be changed by controlling for hydrolysis condition. The uniform surface of thin films was confirmed by SEM. The electrical conductivity of thin films decreased with increasing heat treatment temperature. The humidity sensing properties of thin films were good in high humidity and low frequency regions.

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강제환기를 적용한 이글루형 탄약고 저장환경 개선에 관한 수치적 연구 (Numerical Study on Improvement of Storage Environment of Igloo-Shaped Magazine Using Forced Ventilation)

  • 윤해든;김성훈
    • 한국군사과학기술학회지
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    • 제24권1호
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    • pp.99-106
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    • 2021
  • This study explores the improvement of storage environment of igloo-shaped magazine using forced ventilation. Conjugate heat transfer analysis of forced convection and conduction are performed to calculate the flow, temperature, and relative humidity field in igloo-shaped magazine. Through the conjugate heat transfer analysis, the effects of inlet vent, volume flow rates of jet, and jet angles on the condensation and relative humidity are numerically investigated. The area of condensation in igloo-shaped magazine and relative humidity at the surface of ammunitions are then calculated.

고온 다습한 환경에서의 주관적 착용 쾌적감과 관련 물성 변인 (Subjective Evaluation of Wear Comfort and Related Physical Variables under Warm and Humid Condition)

  • 김정화;홍경희;조승식
    • 한국의류학회지
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    • 제21권6호
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    • pp.1021-1030
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    • 1997
  • Physical variables related to the subjective evaluation of wear comfort were explored. Experimental fabrics was those used in the previous paper where subjective sensations of women's thin shirts were reported. Fabrics include 100% cotton (unfinished), 100% cotton (water repellent finished), cotton/polyester 35/65 (unfinished), cotton/polyester 35/65 (peach skin finished), 100% polyester fabric(plain), 100% polyester crepe. Among various physical properties of the experimental fabrics, heat 8E moisture transport properties and surface properties were chosen as important variables based on the regression coefficient. Especially, humidity at the microclimate in dynamic mode was highly correlated to the subjective evaluation and appeared to be a sensitive physical predictor, compared to dry thermal transmission rate or water vapor transmission rate. Surface characteristic parameters, however, did not show consistant trend in the prediction of the human's subjective sensation. Interaction between surface properties and humidity measurement was also observed.

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SPCP를 이용한 오염물질 ($SO_2$, NOx) 처리 특성 (The Characteristics of the Treatment of Pollutants ($SO_2$, NOx) Using Surface Discharge Induced Plasma Chemical Process)

  • 봉춘근;부문자
    • 한국대기환경학회지
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    • 제14권4호
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    • pp.333-342
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    • 1998
  • Plasma process has great possibilities to remove SOx, NOx simultaneously with high treatment efficiency and is expected to be suitable for small or middle plants. It was accomplished to evaluate SO2, NOx control possibility and achieve basic data to control pollutants by use of Surface Discharge Induced Plasma Chemical Process (SPCP) in this study. O3 generation characteristics by discharge of a plate was proportional to O2 concentration and power consumption and inversely proportional to temperature and humidity, In case of dry air, NOx was highly generated by N2 and O2 in air during the plasma discharge process but it was decreased considerably as H2O was added. SO2 removal efficiency was very high, and removal rate was 170,350 mEA at 30,50 watt respectively in flue gas which is usually contain HIO. NOx removal efficiency was about 57% at 40 watt power consumption with 7.5% humidity. It is estimated that H2O has an important role in reaction mechanism with pollutants according to plasma discharge.

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공동주택 지하주차장의 벽체(壁體) 표면결로방지(表面結露防止)를 위한 적정 공법 선정에 관한 연구 (A Study on the Adoption of optimum Construction Method to prevent Condensation on the wall of Underground Parking Lot in Apartment Project)

  • 오길환;이일재;김성규
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2007년도 추계 학술논문 발표대회
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    • pp.101-104
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    • 2007
  • Currently most of underground structures in domestic apartment projects are being designed for parking lot and essential parking area is growing due to the increase in car-holding number per household. Moreover, most underground parking lots of today are combined with basement, therefore a pleasant environment in underground space is strongly needed for the dwellers' use. However, there always occur high percentage of humidity and surface condensation in underground parking lot because of the nature of underground structure and they are having a bad influence on the comfort and health of dwellers. Therfore, this study is planned to compare and examine the porformance and properties of currently used construction methods to prevent condensation and finally present the most suitable method.

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