• Title/Summary/Keyword: 최소온도

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Relationship Between the Minimum Ignition Energy(MIE) and the Temperature (최소발화에너지와 온도의 관계)

  • 하동명
    • Fire Science and Engineering
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    • v.11 no.2
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    • pp.3-10
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    • 1997
  • Attempts are being made to investigate temperatures dependence of minimum ignition energy (MIE) based on concept of quantity of heat and thermal ignition theory. Regression equations for predicting MIE by means of temperature variations on the basis of statistical and mathematical methods are proposed. This study is undertaken to learn what proposed method is satisfactory hydrocarbons(propane and pentane). The proposed method has been tested and compared sucessfully with previously reported data in various journal.

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Measurement of Flash Points and Autoignition Temperatures for Xylene Isomers (크실렌 이성질체의 인화점과 최소자연발화온도의 측정)

  • Ha, Dong-Myeong;Lee, Sung-Jin
    • Journal of the Korean Institute of Gas
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    • v.13 no.4
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    • pp.40-45
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    • 2009
  • In order to investigate the compatibility of data in MSDS(Material Safety Data Sheet), the flash point of xylene isomer was measured by using Pensky-Martens closed cup (ASTM D93), Setaflash closed cup(ASTM D3278), Tag open cup(ASTM D1310), and Cleveland open cup (ASTM D92) testers. Also, the AITs(autoignition temperatures) of xylene isomers were measured by using ASTM E659-78 tester. The measured the flash points and the AITs were compared with literatures and MSDS in KOSHA(Korea Occupational Safety and Health Agency). The measured the flash points and the AITs were different from those in literatures and MSDS. As a result, this paper is shown that it is needed to investigate combustion characteristics of xylene isomer for the fire safety objectives.

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Measurement of Autoignition Temperature of Ethylbenzene+n-hexanol and Ethylbenzene+n-propionic Acid Systems (Ethylbenzene+n-hexanol 계와 ethylbenzene+n-propionic acid계의 최소자연발화온도의 측정)

  • Ha, Dong-Myeong;Lee, Sung-Jin
    • Fire Science and Engineering
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    • v.21 no.3
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    • pp.33-40
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    • 2007
  • The values of the AITs(Autoignition temperatures) for fire and explosion protection are normally the lowest reported. This study measured the AITs of ethylbenzene+n-hexanol and ethylbenzene+n-propionic acid Systems from ignition delay time(time lag) by using ASTM E659-78 apparatus. The AITs of ethylbenzene, n-hexanol and n-propionic acid which constituted binary systems were $475^{\circ}C,\;275^{\circ}C\;and\;511^{\circ}C$, respectively. The experimental ignition delay time of ethylbenzene+n-hexanol and ethylbenzene+n-propionic acid systems were a good agreement with the calculated ignition delay time by the proposed equations with a few A.A.D.(average absolute deviation).

프로판가스의 자연발화온도 및 폭발한계 예측에 관한 연구

  • 하동명;이수경
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 2001.11a
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    • pp.61-66
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    • 2001
  • 가스 공정에서 취급하는 가연성물질의 연소 특성 파악은 공정의 안전 확보에 가장 중요한 문제이다. 따라서 연소특성들은 가연성물질이 공정의 취급상 부주의로 인해 누출되어 주위에 공기와 혼합되면 화재 및 폭발이 발생할 수 있는 잠재적 위험성을 평가할 수 있다. 연소특성들로는 폭발한계, 인화점, 최소자연발화점, 최소산소농도, 최소발화에너지, 연소열 등을 들 수 있다/sup 1)/.(중략)

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Machine Transplanting Cultivation with Infant Seedling in Rice Plant II. Effects of Raising Temperature, Duration and Nutritional Residue in Endosperm on Seedling Growth after Transplanting. (벼 어린모(유묘) 기계이앙 재배연구 II. 육묘온도, 육묘일수 및 배유양분잔존량이 이앙후 조기생육에 미치는 영향)

  • Yang, Won-Ha;Yun, Yong-Dae;Song, Moon-Tae;Lee, Moon-Hee;Lim, Moo-Sang;Park, Rae-Kyeong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.4
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    • pp.434-439
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    • 1989
  • This study was carried out to investigate the minimum days for raising infant rice seedling with different temperature (day/night $^{\circ}C$ : 20/12, 25/18, 30/20) and to compare with seedling growth and rooting ability at 10 days after transplanting with endosperm-intacted and removed seedlings. The minimum days for raising infant rice seedling was shown differently with different temperatures, thus there were turned out by mat formation to be 10 days at 20/12$^{\circ}C$ (day/night), 8 days at 25/18$^{\circ}C$ and 6 days at 30/20$^{\circ}C$, respectively. Seedling height, leaf number and dry weight of top part at the minimum days for raising infant rice seedling were 8-12cm, 1.5-1.7 leaves and 6.9-7. 5cm per seedling, respectively. The seedling growth at 10 days after transplanting was better at high temperatures (25/18$^{\circ}C$) than low temperature (20/12$^{\circ}C$) at transplanting, and the growth of infant rice seedling with endosperm -intacted was better than that with endosperm-removed. This tedency was shown significantly in transplanting at 20/12$^{\circ}C$ (day/night) of 4 days seedling.

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Temporal Dynamics of Triflumizole Residue in Tomato Leaves as Affected by Temperature and Its Effects on Cladosporium fulvum (토마토 잎에 집적된 Triflumizole 잔류량의 온도에 따른 경시적 동태와 잎곰팡이병균에 대한 약호)

  • 오연이;박은우;조일규;강창성;김성기;양장석
    • Korean Journal Plant Pathology
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    • v.12 no.3
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    • pp.307-315
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    • 1996
  • 토마토 잎에 집적된 triflumizole 잔류량 동태에 미치는 온도 영향과 Cladosporium fulvum에 대한 triflumizole의 살균효과를 구명하였다. 8주간 키운 토마토 식물체에 triflumizole을 분무 살포한 후 식물생장용 항온실에서 키우면서 4가지 온도 조건을 처리하였다. 주기적으로 토마토 잎을 채취하여 HPLC 방법을 이용하여 triflumizole의 잔류량을 조사하였다. Triflumizole 잔류량의 경시적 동태는 약제살포후 적산온도를 독립변수로 사용하는 지수적 감소 몸형으로 나타낼수 있었으며, 이는 triflumizole의 잔류성이 온도 영향을 크게 받는다는 것을 뜻한다. 경기도 농촌진흥원에 위치한 토마토 비닐하우스에서 수행한 실험에서 얻은 자료를 이용하여 평가한 결과 이 모형의 타당성이 인정되었다. Triflumizole의 약효에 대한 in vitro 실험 결과, 이 살균제는 C. fulvum의 균사 생장과 포자형성을 뚜렷이 억제하였으며, 잎곰팡이병 방제를 위해서는 토마토 잎에 집적된 triflumizole 잔류량이 최소한 10 ppm 이상이 되어야 할 것으로 추측된다. 본 연구에서 연구된 지수적 감소 모형은 토마토 잎에 집적된 triflumizole 잔류량을 추정하는데 활용될 수 있으며, 실용적인 측면에서 볼 때, 토마토 잎곰팡이병을 효과적으로 방제하는데 필요한 triflumizole의 최소 잔류량을 식물체에 유지하기 위하여 triflumizole을 살포해야 할 시기를 결정하는데 활용될 수 있다.

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Relationship between Autoigniton Temperature(AIT) and Ignition Delay Time for Acids (산(Acid)류의 자연발화온도와 방화지연시간의 관계)

  • 하동명
    • Fire Science and Engineering
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    • v.18 no.2
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    • pp.27-33
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    • 2004
  • An accurate knowledge of the AIT(Autoignition temperatures) of chemicals is important in developing appropriate prevention and control measures in industrial fire protection. The AITs describe the minimum temperature to which a substance must be heated, without the application of a flame or spark, which will cause that substance to ignite. The measurement AITs are dependent upon many factors. namely initial temperature. pressure, volume, fuel/air stoichiometry. catalyst material, concentration of vapor, ignition delay time. This study measured the AITs of acids from ignition delay time by using ASTM E659-78 apparatus which was produced in the year 1994. The experiment AITs were a good agreement with the calculated AITs by the proposed equations with a few A.A.P.E.(average absolute percent error) and A.A.D.(average absolute deviation).

Measurement of physiological response and estimation of subjective sensation with cool biz (쿨비즈 복장에 의한 생리적 반응 측정과 주관적 감각평가)

  • Gang, Nu-Ri;Lee, Ji-Yeon;Na, Yeong-Ju
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2009.11a
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    • pp.236-238
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    • 2009
  • 에너지 절약차원에서 냉방을 줄여 지구온난화 방지에 일조하고자 여름철에 가벼운 차림의 의복을 권장하는 쿨비즈 캠페인이 시작되었으나 이의 정량적인 효과를 분석하는 연구가 미흡하였다. 본 연구에서는 여름철 온실가스 줄이기 및 직장인 등의 건강증진 등을 위하여 기후복장 적응형에 대한 범국민 인식 및 실천 필요를 바탕으로, 실험을 통해 쿨비즈에 의한 생리적 반응 측정 및 주관적 감각평가를 실시하였다. 1 차실험은 두 복장(전통의복,기후의복)의 피부온 측정실험으로, 환경온 25, $27^{\circ}C$, 상대습도 50% RH 에서 20 대 성인남성 4 명을 대상으로 실험을 하였다. 피험자는 심신을 안정할 수 있도록 30 분간의 안정기를 가진 후에 60 분 동안 실험을 하였으며, 사무실 내 작업환경과 같은 분위기 조성을 위해 편안하게 의자에 앉아 가벼운 대화나 컴퓨터 워드작업 및 설문을 응할 수 있도록 피험자 앞 책상 위에는 노트북을 설치해 두었고, 실험 진행기간 동안 피부온, 직장온, 습도, 발한량, 열화상 카메라, 온열감, 습윤감, 쾌적감 등과 같은 주관적 감각을 측정하였다. 2 차 실험은 동일 피부온 발현하는 환경온 찾기로 기준온도($27^{\circ}C$)에서 전통복장을 입고 온도를 점진적으로 하강시키면서 $27^{\circ}C$ 기후 복장을 입은 상태의 피부온도와 동일해지는 실내온도를 측정한다. 착의 형태에 따른 피부온도 변화에서 환경온도 $25^{\circ}C$ 전통의복 기후의복에 의한 피부온도의 차이는 전통의복이 최소 0.3~최대 $1.6^{\circ}C$ 더 높게 나타났으며, 환경온도 $27^{\circ}C$에서 전통의복 기후의복에 의한 피부온도의 차이는 대체적으로 전통의복이 최소 0.4~최대 $1.0^{\circ}C$ 더 높게 나타났다. 주관적 감각평가에서도 기후의복보다 전통의복에서 온열감 습윤감 불쾌감이 더 높은 경향을 보였다. 주관적 감각으로는 $25^{\circ}C$ 전통의복과 $27^{\circ}C$ 기후의복에서 중립적인 느낌을 나타냈다.

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Precision and accuracy of CARS spectrometer for instantaneous temperature measurement (순간 온도 측정을 위한 CARS 분광기의 정밀 정확도 분석)

  • 박승남;박철융;한재원;길용석;정석호
    • Korean Journal of Optics and Photonics
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    • v.7 no.4
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    • pp.348-356
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    • 1996
  • A mobile CARS spectrometer is constructed to measure the instantaneous temperature of gases, of which software include the quick fit methods and a least square fitting method to obtain temperatures from the spectra. Two quick-fit-methods give smaller variance of temperatures than the least square fitting method even though they consume much shorter time to yield temperatures. The precision and accuracy of CARS temperature is measured in the graphite tube blackbody furnace in reference to a radiation pyrometer. The accuracy of the CARS temperature is $\pm$2% from 1000K to 2400K and the precision is $\pm$35K at 1600K with the most accurate quick-fit-method. As a demonstration of the instantaneous measurement, the spectrometer is applied for measurement of the turbulent combustion at a certain condition. eograms(HS) are made using a relatively small number of synthesized 2D images. The influence of aliasing artifacts caused by insufficient or improper sampling is presented, and a new sampling theory is proposed, which is used to making holographic stereograms. Also, the optical system for extension of viewing distance and viewing zone is proposed. Results of this analysis can be applied to design normal holographic stereograms and computer based holographic stereograms.

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Feasibility study on the development of Liquid crystal-optical fiber temperature sensor for minimal invasive laserthermia (LC(Liquid crystal)-광섬유를 이용한 최소 침습적 레이저 온열 치료용 온도 측정 센서의 개발을 위한 기초 연구)

  • Lee, Bong-Soo;Hwang, Young-Muk;Chung, Soon-Cheol
    • Journal of Sensor Science and Technology
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    • v.12 no.5
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    • pp.225-230
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    • 2003
  • Nowadays, laserthermia is widely used to treat malignant tumors with generating heat as the one of minimal invasive surgeries. Generally, the laserthermia probe system consists of the fiber-optic laser and light guides, image guide and temperature sensor. It is very important to measure the temperature of treating tumor and make a stable temperature ($42{\sim}43^{\circ}C$) during the treating time. Therefore, laserthermia probe needs temperature sensor which can measure it exactly and fast. In this study, to develop a new type of temperature sensor with LC(liquid crystal) and optical fiber, the reflectivity of LC according to the temperature changes are measured. Also, the relationships are derived from the results.