• Title/Summary/Keyword: Relative Humidity

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Analysis of Time Variations in Relative Humidity around a Water Area Using Bowen Ratio

  • Kim, Ki-Young;Kim, Kyu-Rang;Kim, Hae-Dong
    • Journal of Environmental Science International
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    • v.23 no.10
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    • pp.1731-1743
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    • 2014
  • The time variations in relative humidity observed at the Gangjeong (Goryeong) Reservoir in the Nakdong River over a one-year period (September 2012-August 2013) were analyzed with the Bowen ratio. The thermal vertical scale of the reservoir was also evaluated following Yamamoto's method. The study's results showed that the relative humidity at the reservoir was higher than that of the Daegu Meteorological Observatory (inland) all year round. The difference was slightly larger at nighttime (17-20 %) than at daytime (13-15 %) in all seasons except summer. The quantitative order of latent heat flux was summer, spring, autumn, and winter. This finding signifies that the thermal vertical scale of the reservoir corresponds to that of a shallow lake. The Bowen ratio was smallest at midday of the summer season. In other words, the net radiation energy was converted more as latent heat flux than sensible heat flux during a higher temperature period.

A Comparative Functionality Evaluation of Paulownia Wood Storage Boxes and Acid-free Archival Boxes to Store the Annals of Joseon Dynasty - Indoor and Outdoor Temperature and Relative Humidity Controls, and Heat Release Rate -

  • Park, Hae Jin;Kim, Seong Eun;Lee, Jin Kyung;Chung, Yong Jae
    • Journal of Conservation Science
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    • v.38 no.1
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    • pp.72-79
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    • 2022
  • A paulownia wood has been widely used with various advantages as its low weight, permeability, convenient workability and aesthetic patterns for a long time. However, the related empirical researches and simultaneous evaluations of functionality are insufficient compared with acid-free archival boxes for now. In this study, the indoor and outdoor temperature and relative humidity control and heat release rate were evaluated under the controlled and uncontrolled circumstance in 2018. The paulownia wood storage box showed superior control effect of relative humidity than the acid-free archival box in constantly uncontrolled environment. Also, the possibility of the flame diffusion from the surface of the materials was higher for the paulownia materials, and the acid-free archival box showed more dangerous patterns in the early stages of the fire.

A STUDY ON THE INCUBATION OF INDIGENOUS (DESI), KHAKI CAMPBELL AND CROSSBRED (INDIAN RUNNER × KHAKI CAMPBELL, F1) DUCK EGGS UNDER TWO PRE-INCUBATION HOLDING PERIODS

  • Saha, S.K.;Chowdhury, S.D.;Hamid, M.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.3
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    • pp.541-544
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    • 1992
  • Duck eggs from Indigenous (desi), Khaki Campbell and Crossbred (Indian Runner $\times$ Khaki Campbell, $F_1$) were incubated to investigate fertility, hatchability and other related traits. The fertility was highest in crossbred followed by Khaki Campbell and Indigenous ducks respectively. The embryonic mortality was highest in Khaki Campbell followed by Indigenous and crossbred respectively. The embryonic mortality was higher in eggs of 7 days pre-incubation holding period and lower in eggs of 3 days pre-incubation holding period. A significant positive correlation was found between temperature and embryonic mortality as well as relative humidity and embryonic mortality. The hatchability on fertile eggs was highest in crossbred ducks and almost similar in both Khaki Campbell and Indigenous ducks. The hatchability was higher in eggs stored for 3 days in comparison with that of 7 days pre-incubation holding period. A negative correlation was found between temperature and hatchability as well as humidity and hatchability. The normal ducklings hatched out from the eggs of Khaki Campbell ducks was highest followed by Indigenous and crossbred respectively. There was a negative correlation between temperature and normal ducklings hatched as well as relative humidity and normal ducklings hatched. The preincubation holding temperature and relative humidity had positive correlation with dead-in-shell.

Two-Chip Integrated Humidity Sensor Using Thin Polyimide Films (폴리이미드 박막을 이용한 투 칩 집적화 습도 센서)

  • 민남기;김수원;홍석인
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.9
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    • pp.77-86
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    • 1998
  • A two-chip humidity sensor system has been developed which consists of a capacitive sense element die and a CMOS interface chip. The sense element was fabricated using thin polyimide films on (100) silicon substrate and showed excellent linearity(0.72%FS), low hysteresis (<3%) and low temperature coefficient(-0.0285 ~-0.0542pF/K) over a wide range of relative humidity and temperature. The capacitance-relative humidity characteristic exhibited a drift of 2~3% after 9 weeks of exposure to 4$0^{\circ}C$/90%RH. The signal-conditioning circuitry was fabricated using an 1.2- ${\mu}{\textrm}{m}$, one poly double metal CMOS process. The measured output voltage of the sensor system was directly proportional to relative humidity and showed good agreement with theory.

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Change in Curl of Newsprint by Physical Treatments - Effects of roll diameter, storage time, winding methods, calendering and humidity on curl - (물리적 처리에 의한 신문용지의 컬 변화 -권취롤의 직경, 저장 기간, 권취 방법, 캘린더링 및 습도의 영향-)

  • Lim, Yeon-Ju;Paik, Ki-Hyon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.3
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    • pp.60-66
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    • 2004
  • The effects of roll diameter, winding time, winding methods and relative humidity on curl In newsprints(46$g/m^2$, 54 $g/m^2$, and 54 $g/m^2$ SNC) are examined. The larger MD curl appears at smaller roll diameter, with the extension of winding time, and at the treat ment of soft nip calendering. The MD curl shows the back side curl at winding methods with top side as outer side(TSO), and the top side curl with top side as inner side(TSI). While the CD curl in newsprints( 46 $g/m^2$, and 54 $g/m^2$ SNC) treated with calender is hardly influenced by the storage times, roll diameter, and winding methods. However the CD curl in newsprint(54 $g/m^2$) gradually increases to a two weeks, and then hold constant regardless of roll diameter and winding methods.. The CD curl shows always the top side curl regardless of winding methods. At high relative humidity, the CD curl largely reduces, but the MD curl is not nearly changed. Especially, the CD curl in news-prints(54 $g/m^2$ SNC) is little affected by the changes of relative humidity.

A Survey on the Sanitary Condition of Kitchens in School Food-service Programs (일부 학교급식소 조리실의 위생관리에 관한 조사연구)

  • 김종규
    • Journal of Environmental Health Sciences
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    • v.29 no.2
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    • pp.87-93
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    • 2003
  • A survey including an inspection was conducted to assess the sanitary condition of kitchens in the school food-service programs and to prepare background data for improving the safety of school meals. The survey was carried out over a two-month period (September-October, 2001). A self-administered questionnaire recommended by the Korea Ministry of Education & Human Resources Development (MOEHRD) was offered to a random sample of dieticians of twenty-five elementary schools in one region of Korea about food, sanitation, and safety inspection of their kitchens. Air temperature, relative humidity, and airborne microbes in the kitchens were monitored during preparation, cooking, and service. The inspection results showed their sanitary rendition met the level B of the recommendation of the Korea MOEHRD. The range of air temperature of the kitchens was 21.4~22.4$^{\circ}C$. and the range of relative humidity was 62.4~69.6%. The microbiological evaluation of kitchen samples indicated aerobic plate count levels from 22..5 to 26.5 CFU/15 minutes. Although the results of inspection show that the levels of sanitary condition of kitchens in the schools were good, they are not satisfactory for safe food-servile because the temperature and humidity levels are high. This study indicates that the school kitchens should be monitored and strict inspection is necessary. The legal standards for school food-service should include standards for kitchen air temperature, relative humidity, and airborne microbes.

Studies on the Impedance-Hymidity Characteristics of $TiO_2$-$V_2O_5$ Humidity Sensor ($TiO_2$-$V_2O_5$ 습도감지소자의 감습특성에 관한 연구)

  • 박재환;박순자
    • Journal of the Korean Ceramic Society
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    • v.27 no.4
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    • pp.529-535
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    • 1990
  • This paper describes the factors which control the impedance-relative humidity characteristics of the TiO2-V2O5 humidity sensor. To obtain the quantitative relationships between impedance and many manufacturing parameters such as V2O5mol%, the sintering time and temperature, various sets of samples are preared and tested. With changing relative hymidity from 20% to 80%, it is measrued that the corresponding capacitance and impedance from the semicircles which complex impedance plots make. As a result we found that the impedance-relative humidity characteristics are mainly controlled by the doping amount of V2O5 total pore volume and bulk resistence of the elements. We can assume the equivalent circuits of each samples and finally control the sintering time to get a linear humidity impedance response curve which plays an important role in device making. 4mol% V2O5-TiO2 specimen sintered at 90$0^{\circ}C$ for 10min. show liear log(Z) vs. RH characteristics and 10mol% V2O5-TiO2 specimen sintered at the same temp. for 20min. show linear (Z) vs. RH.

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Investigation on Conservation Environment of the Seokguram Grotto (National Treasure No. 24) (국보 제24호 석굴암의 보존환경)

  • Hong, Jung-Ki;Eom, Doo-Sung
    • 보존과학연구
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    • s.24
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    • pp.169-184
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    • 2003
  • Yearly mean temperature and relative-humidity of the Seokguram Grotto was measured $19~23^{\circ}C$, 40~44% from May, 1998 to December,2002. The measurement has little differences comparing to the optimum guideline (temperature : $20^{\circ}\pm2^{\circ}C$, relative-humidity : $50^{\circ}\pm5%$). It is necessary to increase humidity in the Seokguram Grotto during winter because of heating and decrease the temperature during summer because of a higher temperature of outside. In addition, the diurnal range keep in $4^{\circ}C$ of temperature and in 10% of relative-humidity. Yearly mean concentration of $CO_2$(carbon dioxide) was measured538~658ppm that is higher than concentration of normal atmosphere(360 ppm). The $CO_2$ has an cumulative effect on the surface of stone cultural properties as a form of carbonic acid($H_2CO_3$) after reaction with water. HVAC (Heating, Ventilation and Air Conditioning) system should be operated to maintain ideal state for the preservation according to the optimum guideline. Also, the entrance into the Seokguram Grotto should be controlled to prevent a sudden fluctuation of humidity and temperature. Human could carry small particles like a microdust, microbe, etc., into the Seokguram Grotto and also could damage the surface by a direct touch.

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A Study of the Characteristic of Friction Coefficient Variation for the External Environment (외부환경에 따른 마찰재의 마찰계수 변화 특성에 대한 연구)

  • Lee, Girhyoung;Lee, Dongkyu
    • Transactions of the Korean Society of Automotive Engineers
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    • v.23 no.6
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    • pp.601-607
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    • 2015
  • The friction material for automobile is manufactured by mixing several composites to stop the running vehicles. Friction characteristics are changed significantly according to the relative amount of the base materials. However, difference of friction coefficient is sometimes measured at the test for the same friction material. Nevertheless, the study for solving these problems is insufficient. In this paper, the friction tests were carried out by changing the external environment and processing condition when the main ingredients are fixed and also evaluated how the friction coefficient changes. The variables are cooling air speed, humidity (Relative humidity and Absolute humidity), scorching time, soaking time and pad area. And it is analytically considered which environmental factor mainly affects the characteristic of friction coefficient variation by experiment. It is expected that the results from this study can be very useful as a database for development of the friction material.

Super-Resolution Reconstruction of Humidity Fields based on Wasserstein Generative Adversarial Network with Gradient Penalty

  • Tao Li;Liang Wang;Lina Wang;Rui Han
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.5
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    • pp.1141-1162
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    • 2024
  • Humidity is an important parameter in meteorology and is closely related to weather, human health, and the environment. Due to the limitations of the number of observation stations and other factors, humidity data are often not as good as expected, so high-resolution humidity fields are of great interest and have been the object of desire in the research field and industry. This study presents a novel super-resolution algorithm for humidity fields based on the Wasserstein generative adversarial network(WGAN) framework, with the objective of enhancing the resolution of low-resolution humidity field information. WGAN is a more stable generative adversarial networks(GANs) with Wasserstein metric, and to make the training more stable and simple, the gradient cropping is replaced with gradient penalty, and the network feature representation is improved by sub-pixel convolution, residual block combined with convolutional block attention module(CBAM) and other techniques. We evaluate the proposed algorithm using ERA5 relative humidity data with an hourly resolution of 0.25°×0.25°. Experimental results demonstrate that our approach outperforms not only conventional interpolation techniques, but also the super-resolution generative adversarial network(SRGAN) algorithm.