• 제목/요약/키워드: Temperature index

검색결과 2,661건 처리시간 0.039초

실내 내장 벽지의 고온산소지수에 대한 연구 (A Study on the Oxygen Index of Interior Wallpapers at Elevated Temperature)

  • 오규형;이성은;김황진
    • 한국화재소방학회논문지
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    • 제22권2호
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    • pp.57-62
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    • 2008
  • 한국의 실내장식재로는 대부분 벽지를 사용하고 있다. 이러한 주거공간에 화재발생시 화재 확대요인중의 하나는 벽지의 연소를 통해 이루어진다. 그동안 산소지수 관련연구들이 많이 이루어져 왔지만 상온에서의 연구가 많았다. 본 연구에서는 실내화재에서 화재의 확대요인이 될 수 있는 벽지의 산소지수가 상온과 고온에서 얼마나 차이가 발생하며 이러한 차이가 화재확대에 미치는 영향을 고찰하고자 하였다. 실험을 통해 LOI 및 TOI 측정한 결과 벽지의 상온과 고온에서의 산소지수는 $5{\sim}8%$정도의 차이가 나타났다. 실험에서 산소지수 0.1%의 차이로도 연소 길이에 현저한 차이가 나타나기 때문에 고온에서의 산소지수 감소가 화재확대에 큰 영향을 미치는 요인임을 알 수 있었다.

반응시간지수(Response Time Index)를 이용한 국내 화재감지기 등급분류에 관한 연구 (A Study on the Classification of Domestic Fire Detector using Response Time Index)

  • 홍성호;김동석;최기옥
    • 한국안전학회지
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    • 제32권2호
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    • pp.46-51
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    • 2017
  • This paper presents classification of domestic fire detector using response time index. Response time is measured using fire detector distributed in Korea, and the response time index is estimated. Plunge test prescribed by FM is conducted to measure response time of fire detector. The detector used to test is fixed temperature type(thermistor and bimetal type) and rate of rise temperature type(thermistor and pneumatic type). The nominal operation temperature of fixed temperature type detector is $70^{\circ}C$ and rate of rise temperature is $15^{\circ}C/min$. The fixed temperature type is measured 7 products, and the rate of rise temperature type is measured 5 products. The results show that in case of fixed temperature type(thermistor) is classified "Quick" or "Standard" and fixed temperature type(bimetal) is not classified. The rate of rise temperature type(thermistor) is classified "Fast" or "Ultra Fast" and the rate of rise temperature type(pneumatic) is classified "Very Fast" or "Ultra Fast". The pneumatic type shows more fast response than thermistor type. Also these results indicate the fixed temperature type(bimetal) is not suitable for early stage fire detection.

광섬유 브래그 격자가 포함된 측면 연마된 광섬유를 이용한 매질의 온도와 굴절률 동시 측정 (Simultaneous Measurement of Temperature and Refractive Index of a Medium Using by a Side-Polished Fiber Containing a Fiber Bragg Grating)

  • 김광택
    • 한국전기전자재료학회논문지
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    • 제28권8호
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    • pp.513-517
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    • 2015
  • We proposed and demonstrated a simultaneous measurement method to detect the refractive index and temperature of a medium using a side-polished fiber involving FBG (fiber Bragg grating). The temperature of a medium was obtained by using the Bragg wavelength shift of FBG, while the refractive index of medium were calculated by using the transmission loss. The Bragg wavelength is independent on the refractive index of the covering medium placed on surface of side-polished fiber, while the transmission loss at off-Bragg wavelength highly depends on the environmental temperature because of thermo-optic effect of the medium.

한반도의 날씨 스트레스 지수 NET(Net Effective Temperature) 분포의 특성 (The Spatial and temporal distributions of NET(Net Effective Temperature) with a Function of Temperature, Humidity and Wind Speed in Korea)

  • 허인혜;최영은;권원태
    • 대한지리학회지
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    • 제39권1호
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    • pp.13-26
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    • 2004
  • 본 연구는 상대적 날씨 스트레스 지수로 NET의 적용 가능성을 파악하고자 하였다. 기상청에서 예보하고 있는 기온, 습도, 바람 자료를 이용하여 NET 값의 시공간적 분포 특성을 분석하였다. 여름철 스트레스 지수인 일 최고 NET의 지역별 스트레스 기준값은 바람과 습도보다는 기온의 영향을 받으므로 일 최고 기온의 분포와 유사하다. 겨울철 스트레스 지수인 일 최저 NET의 스트레스 기준값은 산지 지역과 서울 이북 지역에서는 낮은 기온의 영향을. 해안 지역에서는 강한 바람의 영향으로 기준값이 여름철에 비하여 다양하게 나타난다. 스트레스가 강한 날의 발생 빈도는 여름철은 뚜렷한 연변화가 나타나지 않지만, 겨울철에는 1990년대 중반 이후 뚜렷한 증가 경향을 보인다.

온실작물의 관개계획의 수립을 위한 엽온의 활용 (Using Leaf Temperature for Irrigation Scheduling in Greenhouse)

  • 이남호;이훈선
    • 한국농공학회지
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    • 제43권6호
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    • pp.103-112
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    • 2001
  • The development of infrared thermometry has led many researchers to use plant temperatures, and specifically the temperature of the crop canopy in the field, for estimating the water stress of a crop. The purpose of this study was to evaluate the role of leaf temperature in irrigation scheduling. An experiment was carried out in a greenhouse with chinese cabbage. Leaf temperature was measured with infrared thermometry and evapotranspiration of the crop was measured by lysimeters. Influence of the difference between leaf temperature and air temperature on crop evapotranspiration was evaluated under varying water stress condition. A further objective was to evaluate the effect of other climatic variables on the relationship between evapotranspiration and temperature difference between leaf and air. A statistical model for estimating evapotranspiration using the temperature difference, relative humidity. and radiation was developed and tested. Crop water stress index was calculated using vapour pressure deficit and the temperature difference. Relations between the crop water stress index and crop evapotranspiration was tested. The index was closely related with evapotranspiration.

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Temperature Stabilization of Group Index in Silicon Slotted Photonic Crystal Waveguides

  • Aghababaeian, Hassan;Vadjed-Samiei, Mohammad-Hashem;Granpayeh, Nosrat
    • Journal of the Optical Society of Korea
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    • 제15권4호
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    • pp.398-402
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    • 2011
  • In this paper, we have proposed a principle to design wideband, low dispersion and temperature stabilized slow light structure in slotted photonic crystal waveguide (SPCW). The infiltration of the silicon photonic crystal with polymer will enhance the slow light and increase the group index, whereas the different signs of thermo-optic coefficients of polymer and silicon make the proposed structure stable on temperature variation over $60^{\circ}C$ and improves the group index-bandwidth products of the designed structure. The SPCW structure is modified to maximize the slow light effect and minimize the dependence of the group index and hence the group velocity dispersion to temperature.

한반도 2007년 여름철 인지온도 특성 연구 (A Study on the Characteristics of Perceived Temperature over the Korean Peninsula During 2007 Summer)

  • 변재영;김정식;김지영;최병철;최영진
    • 대기
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    • 제18권2호
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    • pp.137-146
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    • 2008
  • This study examines one thermal index, perceived temperature (PT), over the Korean Peninsula during 2007 summer. Heat/cold stress has been described using air temperature and humidity for warm seasons and air temperature and wind velocity in the cold conditions, while PT is based on a heat budget model of the human body that considers air temperature, humidity, wind velocity and radiation effect regardless of climates, regions and seasons. PT is higher about $4-5^{\circ}C$ than air temperature in the summer. Humidity increases PT, while wind tends to reduces PT possibly by evaporation of water vapor. The geographical distribution of summer PT indicates that the lowest PT happened in the east central region, with the appearance of the highest PT in the inland of southern region in Korea. Although the latitudinal trend shows that PT decreases northward, inland PT is higher than that of coastal region. Compared to the heat index or the discomfort index that considers air temperature and humidity, PT represents distinctive regional characteristics of thermal comfort. The distribution of PT shows that it may be a useful thermal index for the assessment of thermal comfort or stress region in the Korean Peninsula.

NOAA/AVHRR 자료 응용기법 연구 - 운정.지표온도, 반사도, 해수면 온도, 식생지수, 산불, 홍수 분석 - (A Study on the Application of NOAA/AVHRR Data -Analysis of cloud top and surface temperature,albedo,sea surface temperature, vegetation index, forest fire and flood-)

  • 이미선;서애숙;이충기
    • 대한원격탐사학회지
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    • 제12권1호
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    • pp.60-80
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    • 1996
  • AVHRR(Advanced Very High Resolution Radiometer) on NOAA satellite provides data in five spectral, one in visible range, one in near infrared and three in thermal range. In this paper, application of NOAA/AVHRR data is studied for environment monitoring such as cloud top temperature, surface temperature, albedo, sea surface temperature, vegetation index, forest fire, flood, snow cover and so on. The analyses for cloud top temperature, surface temperature, albedo, sea surface temperature, vegetation index and forest fire showed reasonable agreement. But monitoring for flood and snow cover was uneasy due to the limitations such as cloud contamination, low spatial resolution. So this research had only simple purpose to identify well-defined waterbody for dynamic monitoring of flood. Based on development of these basic algorithms, we have a plan to further reseach for environment monitoring using AVHRR data.

점탄성유체의 점성에 관한 실험적 연구 (An experimental study on the viscosity of visco-elastic fluids)

  • 김춘식;이영호
    • Journal of Advanced Marine Engineering and Technology
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    • 제6권2호
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    • pp.21-41
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    • 1982
  • Viscosity, especially characteristic among various properties of visco-elastic fluids such as high polymer solutions, is affected mainly by temperature and concentration. Hence, it is important for fluid engineering to express, by some equations, how the fluid characteristics vary with the change of temperature and concentration and to analyze them to obtain consistent viscous characteristics. High polymer solutions, synthetic products of modern chemical industry, suggest many interesting investigations because they are typical visco-elastic materials. Experimentation was made to derive some useful fluid characteristic equations of SEPARAN-NP10 (polyacylamide) expressed by n (flow behavior index) and K' (consistency index) when it is given temperature and concentration variation. To measure viscosity, capillary viscometer was adopted and the range of experimentation is 0-2,000 P.P.M. in concentration and 15-55 .deg.C in temperature. The experimental results are summarized as follows: The flow behavior index n 1) has nearly constant results irrespective of temperature variation at same conentration and the results are shown in (Table. 4-4-3) 2) has following equation, regardless of temperature, for the variation of concentration. n=-1.0765*10$^{-4}$ P+0.9915 (P:P.P.M.) The consistency index K' 1) has different results for the variation of temperature at same concentration and the results are given in (Table.4-7-2) 2) has following equation for the variation of concentration at same temperature. log 10$^{4}$K' =6.4785*10$^{-4}$ P-1.0529 (P:P.P.M)

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농도와 온도에 따른 흰죽의 리올로지 특성 변화 (Changes in the Rheological Characteristics by Various Concentrations and Temperatures of Korean white Gruel)

  • 이창호;한억
    • 한국식품조리과학회지
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    • 제11권5호
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    • pp.552-556
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    • 1995
  • The rheological properties of Korean white gruel at various concentrations (4-7%) and temperatures (30-60$^{\circ}C$) were investigated. The rheological behavior of Korean white gruel was evaluated by Herschel-Bulkley equation and showed typical Bingham psedoplastic behavior with yield stress. Flow behavior index was increased at over 5% of rice content. Consistency index was increased by the increase of concentration of rice. But, measuring temperature was not effected in the flow behavior index and consistency index. Yield stress was increased by the incerase of concentration of rice and the decrease of measuring temperature. The activation energy of flow of Korean gruel increased from 7.646 to 32.949${\times}$10/Sup 6/ J/Kg$.$ mole by increasing concentration from 4% to 7%. As the temperature increased from 30$^{\circ}C$ to 60$^{\circ}C$, B-value decresed from 1.214 to 0.947 Flow behavior index and consistency index was reduced during storage.

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