• Title/Summary/Keyword: Humidity variation

Search Result 403, Processing Time 0.026 seconds

Characteristics of Climate in the Eastern Coastal Regions of Korean Peninsula (한반도 동해안 지방의 기후 특성)

  • KIM Young-Seup;HAN Young-Ho;SHIN Soo-Kyeong;HONG Sung-Kun
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.27 no.3
    • /
    • pp.314-325
    • /
    • 1994
  • Characteristics of climate in the eastern coastal regions of Korean Peninsula were studied using the meteorological and coastal sea surface temperature (SST) data which were compiled from 1961 to 1990. In the winter half year (from October to March), air temperature (AT) and precipitation of the eastern coastal regions were considerably higher than those of the western and inland regions, but relative humidity was $8{\sim}15\%$ lower. AT of coastal regions was closely related to the variation of coastal SST. These characteristics were more noticeable in the eastern coastal areas and in lower latitude regions. Quantitatively, the $1.0^{\circ}C$ variation of coastal SST may have resulted in the $1.0^{\circ}C{\sim}1.5^{\circ}C$ variation for AT in coastal regions. In the same way as temperature, vapor pressure in coastal regions was also influenced by coastal SST. Relative humidity change corresponding to the $1.0^{\circ}C$ variation of coastal SST was $3.7\%{\sim}6.5\%$. Net heat exchange amounts were positive (sea surface gaining energy) in all coastal regions. Sea surface gained net heat from March to September, and lost it from October to February. Variation of AT in coastal regions was also related to the sensible and latent heat exchanges. Sensible and latent heat amount corresponding to the $1.0^{\circ}C$ variation of AT were $10Wm^{-2}$ at Kangnung, and $8Wm^{-2}$ at Pohang and $13Wm^{-2}$ at Pusan.

  • PDF

On the Prediction and Variation of Air Pollutants Concentration in Relation to the Meteorological Condition in Pusan Area (기상조건에 따른 부산지역 대기오염물질 농도변화와 예측에 관한 연구)

  • 정영진;이동인
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.14 no.3
    • /
    • pp.177-190
    • /
    • 1998
  • The concentrations of air pollutants In large cities such as Pusan area have been increased every year due to the increasing of fuels consumption at factories and by vehicles as well as the gravitation of the population. In addition to the pollution sources, time and spatial variation of air pollutants concentration and meteorological factors have a great influence on the air pollution problem. Especially , its concentration is governed by wind direction, wind speed, precipitation, solar radiation, temperature, humidity and cloud amounts, etc. In this study, we have analyzed various data of meteorological factors using typical patterns of the air pressure to investigate how the concentration of air pollutants is varied with meteorological condition. Using the relationship between meteorological factors (air temperature, relative humidity, wind speed and solar radiation) and the concentration of air pollutants (SO2, O3) , experimental prediction formulas for their concentration were obtained. Therefore, these prediction formulas at each meteorological factor in a pressure pattern may be roughly used to predict the air pollutants concentration and contributed to estimate the variation of its value according to the weather condition in Pusan city.

  • PDF

The Relationship of Particulate Matter and Visibility Under Different Meteorological Conditions in Seoul, South Korea (서울의 기상 조건에 따른 미세먼지와 시정의 상관성)

  • Kim, Minseok;Lee, Seoyoung;Cho, Yeseul;Koo, Ja-Ho;Yum, Seong Soo;Kim, Jhoon
    • Atmosphere
    • /
    • v.30 no.4
    • /
    • pp.391-404
    • /
    • 2020
  • To understand the characteristics of the relationship between visibility and particulate matter (PM) in different meteorological conditions, we investigated the contributions of PM and relative humidity (RH) to visibility in Seoul, South Korea. For the period from 2001 to 2018, both PM and RH show descending trends, resulting in a visibility increase. PM has little impact on the hourly variation of visibility, which could be explained more by the RH variability. Meanwhile, the daily change of PM accounts for daily visibility variation. For the monthly variation of visibility, both PM and RH showed similar influence. The correlation coefficients of PM10, PM2.5, and RH with visibility was -0.486, -0.644, and -0.556, respectively, which became higher during the high PM seasons of spring and winter. The correlation coefficient between PM2.5 and visibility was -0.454 for RH higher than 80%, and -0.780 for RH between 40% and 60%. From 2017 to 2018, there were 10 cases of extreme visibility impairment, among which five cases were incurred by high PM pollution, and two cases were by high humidity. Further analysis with PM chemical composition measurements is required to better understand the characteristics of visibility in Seoul.

The observation of Temperature and Humidity in Dirt walled Storehouse manufactured as reduced scale (축소제작된 흙담저장고의 온습도 변화 관측)

  • Eom, Seong-Jun;Rhee, Shin-Ho;Kim, Jai-Shik;Jang, Moon-Ki
    • Proceedings of the Korean Society of Agricultural Engineers Conference
    • /
    • 2002.10a
    • /
    • pp.73-76
    • /
    • 2002
  • The temperature and humidity of dirt-walled storehouse are observed in order to verify the traditional storehouse (main material : soil) during 7days (4th. $Sep{\sim}10th$. Sep). Because the width of the daily variation of temperature is small as $2.5^{\circ}C{\sim}5^{\circ}C$, the reduction of energy supply for low temperature is expected. Because the relative humidity is high and it's variation is small ($4%{\sim}9%$), the inner humidity of dirt-walled storehouse is easily maintained above 80% is expected.

  • PDF

Environmental Analysis of a Windowless Delivery Swine Building : Temperature and Relative Humidity (무창분만돈사의 온.습도 환경 분석)

  • 이성현;조한근;장유섭
    • Journal of Animal Environmental Science
    • /
    • v.3 no.2
    • /
    • pp.77-85
    • /
    • 1997
  • Recently, local swine producers are rapidly adopting the indoor production system which developed in foreign countries. However, this imported system is reported as not functioning properly because of different climate conditions. The objective of this project was to investigate the environment characteristics of a windowless delivery swine building. The parameters studied were the heating and cooling loads, the daily changes of indoor temperature and relative humidity, the horizontal and the vertical distributions of indoor temperature, and the effect of mist cooling on indoor temperature. From this study, the following are founded : 1. The maximum cooling and heating loads were - 317.0kcal/㎡$.$h and 336.5kal/㎡$.$h in summer and in winter. The large loads seems to be on account of inappropriate operations of ventilating fans. 2. The daily variations of relative humidity in indoor were smaller than those in outside. Those values both in summer and in winter as relative humidities in door was lower than optimum for growing pigs, the additional humidifier might be helpful to increase the relative humidity in indoor. 3. The horizontal distribution of the indoor temperature was found to be uniform in the variation range of 1$^{\circ}C$. 4. The vertical distribution of the indoor temperature was not found to be uniform; the temperature of upper part was higher than that of slot part. 5. Average values of indoor temperature became lower by 3$^{\circ}C$ by mist cooling. But the variation of temperature was found to be larger; The middle part of the room was cooled down, but the corner part of the room was not affected by misting due to uneven nozzle configuration.

Experimental Study on Capacity Variation of Paving Materials with TiO2 in Wet Condition (광촉매 이산화티타늄(TiO2)을 혼합한 도로 포장재의 습윤 조건에서의 성능 변화에 관한 실험적 연구)

  • Seo, Dawa;Yun, Tae Sup
    • Journal of the Korean Geotechnical Society
    • /
    • v.32 no.5
    • /
    • pp.49-55
    • /
    • 2016
  • This study aims to present the practical Nitrogen monoxide (NO) removal capacity of cement mortar with Titanium dioxide ($TiO_2$) which is one of the paving materials by considering the environment of pavement in urban areas. NO removal capacity test under designated conditions of humidity of inflow gas and the test with variation of the degree of saturation of specimen were conducted. In the test for humidity, dry specimen is subject to the test and NO removal ratio was observed. Humidity-NO removal ratio curve is a log normal distribution in shape, and the maximum NO removal ratio appears at specific humidity. NO removal capacity test relying on the degree of saturation was carried out with wet specimen to reflect the unsaturated pavement by rainfall and domestic sewage. Wet specimen presents less NO removal capacity than dry specimen and the recovering evolution of NO removal capacity follows evaporation. Moreover, $TiO_2$ under the specific depth of specimen hardly contributes to NO removal capacity.

Performance Test of Proton Exchange Membrane Fuel Cell with the Variation of Operation Condition (이온교환막 연료전지용 막 가습기의 운전 조건에 따른 성능 실험)

  • Bae, Ho-June;Kim, Yong-Mo;Lee, Young-Duk;Yu, Sang-Seok
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.6-9
    • /
    • 2008
  • The efficiency and life time of the proton exchange membrane (PEM) fuel cell system is critically changed with its humidity which should be maintained properly during dynamic operation. Membrane humidifier is required to regulate proper humidity level for the design point of the PEMFC system. In this study, we presented the performance of the cylindrical membrane humidifier which is operated as water-to-gas. Dry air pressure, liquid water flow temperature, and air flow rate were chosen as the operating parameters. Humidity level is expressed with dew point.

  • PDF

Electrical Conductivity of Vacuum Evaporated Al Films on Glass (유리표면에 진공증착된 Al박막의 전기전도성)

  • 김동호;박현수;정창주;최석진
    • Journal of the Korean Ceramic Society
    • /
    • v.24 no.2
    • /
    • pp.101-110
    • /
    • 1987
  • The relative electrical conductivity of vacuum deposited Al films on a soda-lime(2947) and an alumino boro silicate(7809) glass was investigated with the variation of the relative humidity,temperature and film thickness. The structure and microstructure of Al films before and after exposure to the humidity wereexamined by the X-ray Diffractormenter(XRD) and Scanning Electron Microscope(SEM). As the relative humidity increased, the electrical conductivity of Al films on both glasses was decreased. However, the Al films on 7809 glass showed higher conductivity than that of 2947 glass under the same testing conditions. The decreasing of electrical conductivity was caused by the formation of Aluminum hydroxide which was made by the reaction between the aluminum films and water vapor.

  • PDF

Comparison of Meteorological Elements by Type of City during Summer Season - Focus on the Daegu Metropolitan City and the Surrounding Four Regions - (하절기 도시 유형별 기상요소 비교 -대구광역시와 인근 4개 지역을 중심으로-)

  • Choi, Dong-Ho;Lee, Bu-Yong;Jeong, Hyeong-Se
    • Journal of the Korean Solar Energy Society
    • /
    • v.34 no.6
    • /
    • pp.111-122
    • /
    • 2014
  • The purpose of this study is to understand relation of meteorological elements of air temperature, relative humidity and vapor pressure of four cities with Daegu. The followings are main results from this study. 1) There is very high correlation of meteorological elements according to distance between city and city. 2) In case of seaside town at Pohang, there were little changes than other cities for temperature, humidity and vapor pressure. 3) It was analysed stable and similar diurnal variation in water vapor pressure than air temperature and relative humidity at all observation site.

The change on characterizations of fruiting body according to the growing humidity in Flammulina velutipes (팽이버섯 생육습도에 따른 균주별 자실체의 특성 변화)

  • Jhune, Chang-Sung;Yun, Hyung-Sik;Kong, Won-Sik;Lee, Chan-Jung;Chung, Jong-Chun;Yoo, Young-Bok
    • Journal of Mushroom
    • /
    • v.8 no.3
    • /
    • pp.109-115
    • /
    • 2010
  • We investigated the morphological traits, hardness and color of fruting bodies on eight strains according to changes of the humidities in mushroom house in Flammulina velutipes. The morphological traits like length and thickness of stipe, diameter and thickness of pilei didn't show any relations to humidity. Variation of these traits were rather showed by strains. ASI 4065 and ASI 4031 produced the longest stipes and ASI 4103 did the shortest ones. Fruiting body of ASI 4103 showed the most thickness of stipe, diameter and thickness of pilei. The pilei of ASI 4065, ASI 4021 and the stipe of ASI 4153 was the thinest. Brightness (L) values of white strains were increased at the low humidity except ASI 4021. But chroma (a, b) value showed little variation according to the humidity. L value of brown strains usually increased at the low humidity and a chroma (a, b) value showed little variation according to the humidity. But the chroma (a) value of pilei increased and the chroma (b) value of pilei decreased at the hight humidity. Most strains were brighter at pilei than at stipes. Hardness were not any relations to the humidity. In general, hardness of stipes were higher than that of pilei and their degrees were different according to strains. Hardness of ASI 4021 was the highest and ASI 4166 was the lowest. White strains were higher than brown strains at the hardness. As a result, hardness was rather affected by strains than by humidity.

  • PDF