• Title/Summary/Keyword: High humidity

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Adsorption Characteristics of a Respirator Cartridge for Organic Vapor Packed with Activated Carbon Fiber (활성탄소섬유가 충전된 유기가스용 방독마스크 정화통의 흡착특성)

  • Shin, Chang-Sub;Kim, Ki-Hwan;Kang, Young-Goo
    • Journal of the Korean Society of Safety
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    • v.15 no.2
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    • pp.84-91
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    • 2000
  • The adsorption characteristics of a respirator cartridge is affected by the kind of adsorbent, concentration of organic vapor, humidity and packing density of cartridge. In this study, activated carbon fiber(ACF) instead of activated carbon is used as a adsorbent of cartridges for the removement of organic vapor and the adsorption characteristics were examined. ACF made of cellulose showes high efficiency for the removal of carbon tetrachloride and the adsorption capacity was 0.569g/g ACF at 450 ppm. The relative humidity dose not affected to the adsorbed amount and Langmuir Isotherm was more adequate than Freundlich Isotherm for this adsorption phenomena.

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ANN Modeling of a Gas Sensor

  • Baha, H.;Dibi, Z.
    • Journal of Electrical Engineering and Technology
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    • v.5 no.3
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    • pp.493-496
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    • 2010
  • At present, Metal Oxide gas Sensors (MOXs) are widely used in gas detection because of its advantages, including high sensitivity and low cost. However, MOX presents well-known problems, including lack of selectivity and environment effect, which has motivated studies on different measurement strategies and signal-processing algorithms. In this paper, we present an artificial neural network (ANN) that models an MOX sensor (TGS822) used in a dynamic environment. This model takes into account dependence in relative humidity and in gas nature. Using MATLAB interface in the design phase and optimization, the proposed model is implemented as a component in an electronic simulator library and accurately expressed the nonlinear character of the response and that its dependence on temperature and relative humidity were higher than gas nature.

Seasonal Variation of Nitrate in the Greater Seoul Area Using a Photochemical Box Model and a Gas/Aerosol Equilibrium Model (광화학 상자모델과 기체/입자 평형모델을 이용한 서울ㆍ수도권의 계절별 질산염 농도 변화)

  • Lee S.;Ghim Y. S;Kim Y. P;Kim J. Y
    • Journal of Korean Society for Atmospheric Environment
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    • v.20 no.6
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    • pp.729-738
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    • 2004
  • Seasonal variation of major inorganic ions in the greater Seoul area was estimated using a photochemical box model and a gas/aerosol equilibrium model with emphasis on semi -volatile nitrate. Pollutant emission was determined by season by comparing the predicted concentration with the measurement one obtained for a year from the late 1996. The results showed that particulate nitrate was the highest in summer but about 40% of total nitrate was present in the gas phase. This was due to volatilization at high temperature since ammonia was sufficient to neutralize all nitrate regardless of season. As relative humidity in summer was higher than the deliquescence point, particulate ion concentration with water was two times higher than that in other season. So called ‘NOx disbenefit’ indicating increase in particulate ion concentration with decrease in NOx emission was evident especially in winter.

Cloud Forecast using Numerical Weather Prediction (수치 예보를 이용한 구름 예보)

  • Kim, Young-Chul
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.15 no.3
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    • pp.57-62
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    • 2007
  • In this paper, we attempted to produce the cloud forecast that use the numerical weather prediction(NWP) MM5 for objective cloud forecast. We presented two methods for cloud forecast. One of them used total cloud mixing ratio registered to sum(synthesis) of cloud-water and cloud-ice grain mixing ratio those are variables related to cloud among NWP result data and the other method that used relative humidity. An experiment was carried out period from 23th to 24th July 2004. According to the sequence of comparing the derived cloud forecast data with the observed value, it was indicated that both of those have a practical use possibility as cloud forecast method. Specially in this Case study, cloud forecast method that use total cloud mixing ratio indicated good forecast availability to forecast of the low level clouds as well as middle and high level clouds.

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Characterization of a Loess Module for Manufacturing Loess Red Ginseng

  • Kim, Il-Chool;Yang, Jung-Hwan;Hur, Sang-Sun
    • Journal of Ginseng Research
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    • v.34 no.4
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    • pp.282-287
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    • 2010
  • An optimized manufacturing process was developed for the production of high-quality loess red ginseng using a hybrid process in which loess (yellow earth) was incorporated into the conventional ginseng manufacturing process system. We designed conventional ginseng processing facilities and prepared the loess module by baking loess that contained 42% water at $860^{\circ}C$ for 8 h. The loess module showed excellent performance in deodorization and humidity control. The optimum steaming temperature at which maximum expansion of starch organisms occurred was 90 to $98^{\circ}C$.

Desalting Method for Removing $Cl^-$ Ions from the Exacavated Irons Objects (출토 철제 유물의 탈염 처리 방법 고찰)

  • Moon, Whan-Suk;Hwang, Jin-Ju;Jung, Young-Dong
    • 보존과학연구
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    • s.17
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    • pp.1-19
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    • 1996
  • Desalting methods for chloride ions from the excavated iron objects were studied. These methods were compared with room temperature and heating condition of treating solution. During the Desalting treatments the $Cl^-$concentration of the solution were measured regularly and the plotted for $Cl^-$concentrations the square root of time, heating methods showed that the $Cl^-$ ions are more extracted. For the desalting treatments these plots were found to be flattening line, it was showed the changing second solution. Also, the changing solution in the room temperation detected less $Cl^-$ ions of heating treatment solution. As the examination for the relative humidity has compared for desalting objects during 8 days, it was showed a re-corroded appearance of R.H90%. As it did not detected a $Cl^-$ ions of re-corroded section, these phenomena were showed the naturally occuring corrosion of the objects in the high relative humidity.

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

  • Oh, Kil-Hwan;Lee, Il-Jae;Kim, Sung-Gyu
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2007.11a
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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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An Experimental Study on the Prediction of Concrete Compressive Strength by the Maturity Method Using Embedded Wireless Temperature and Humidity Sensor (콘크리트 매립형 무선 온습도 센서 기반 적산온도법을 이용한 콘크리트 압축강도 예측에 관한 실험적 연구)

  • Mun, Dong-Hwan;Jang, Hyun-O;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.11a
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    • pp.94-95
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    • 2018
  • Prediction of compressive strength of concrete by Maturity Method is applied in construction site. However, due to the use of wired type high-priced equipment, economic efficiency and workability are falling. In this study, a newly developed concrete embedded wireless sensor is used to perform a mock-up test. Next, the concrete compressive strength of the Maturity Method is predicted using Saul and Plowman's function as measured temperature data. The predicted concrete strength at the beginning of the age was the actual strength and stiffness, but the error rate was less than 1% at 28th day.

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Effects of Vertical Meteorological Changes on Heating and Cooling Loads of Super Tall Buildings

  • Song, Doosam;Kim, Yang Su
    • International Journal of High-Rise Buildings
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    • v.1 no.2
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    • pp.81-85
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    • 2012
  • Vertical meteorological conditions encountered by super tall buildings, such as wind speed, temperature and humidity, vary due to their height. Therefore, it is necessary to consider these environmental changes to properly estimate the heating and cooling loads, and to minimize the energy demands for HVAC in super tall buildings. This paper aims to analyze how vertical meteorological changes affect heating and cooling loads of super tall buildings by using numerical simulation. A radiosonde, which observes atmospheric parameters of upper air such as wind speed, wind direction, temperature, relative humidity and pressure, was used to provide weather data for the building load simulation. A hypothetical super tall building was used for the simulation to provide quantified characteristics of the heating and cooling loads, comparing the lower, middle and upper parts of the building. The effect of weather data on the heating and cooling loads in super tall building was also discussed.

Characteristics of thermal comfort for artificial environment experiment in summer (하계 인공환경실험에서의 온열쾌적특성)

  • 박종일;김경훈;홍희기;민병일;김창주
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.3
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    • pp.368-377
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    • 1998
  • The purpose of this study was to examine theory about indoor thermal comfort-environment as well as to determine thermal sensation and physiological responses for men in summer indoor environment, under various air temperature and relative humidity, with male university students. Subjective Evaluation, Heart Rate(Electrocardiogram), Electroencephalogram(EEG) were examined. We found that comfort of people was achieved at SE $T^{*}$ 24.7$^{\circ}C$, -0.82<PMV<0.93, subject's clothing(0.41c1o)and the difference of skin temperature was found at the calf area as air temperature changes. At low SE $T^{*}$, heart rate was decreased and at high SE $T^{*}$, heart rate was increased but there was no change EEG(keeping $\alpha$-wave).wave).

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