• Title/Summary/Keyword: Inside temperature

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Estimation of Thermal Humidity Inside Concrete and Prediction of Carbonation Depth (콘크리트 내부 온습도 추정 및 탄산화 깊이 예측)

  • Park, Dong-Cheon
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.197-198
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    • 2021
  • The temperature and humidity inside concrete affects the depth of carbonation. In this study, the temperature and humidity inside concrete were predicted by the numerical method under the boundary conditions of ambient temperature, humidity, solar radiation, and wind. Using the results of the thermal humidity analysis, diffusion of carbon dioxide and the reaction of cement hydration products were calculated for carbonation depth.

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Fabrication of a novel micromachined measurement device for temperature distribution measurement in the microchannel (마이크로채널 내의 온도 분포 측정을 위한 미소 측정 구조물의 제작)

  • Park, Ho-Joon;Lim, Geun-Bae;Son, Sang-Young;Song, In-Seob;Pak, James-Jung-Ho
    • Proceedings of the KIEE Conference
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    • 2001.07c
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    • pp.1921-1923
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    • 2001
  • In this work, an array of resistance temperature detector(RTD) was fabricated inside the microchannel in order to investigate in-situ flow characteristics. A rectangular straight microchannel, integrated with RTD's for temperature sensing and a heat source for generating the temperature gradient along the channel. were fabricated with the dimension of $200{\mu}m(W){\times}{\mu}m(D){\times}$48mm(L), while RTD measured precise temperatures at the inside-channel wall. 4" $525{\pm}25{\mu}m$ thick P-type <100> Si wafer was used as a substrate. For the fabrication of RTDs. 5300$\AA$ thick Pt/Ti layer was sputtered on a Pyrex glass wafer. Finally, glass wafer was bonded with Si wafer by anodic bonding, therefore RTD was located inside the microchannel. The temperature distribution inside the fabricated microchannel was obtained from 4 point probe measurements and Dl water is used as a working fluid. Temperature distribution inside the microchannel was measured as a function of mass flow rate and heat flux. As a result, precise temperatures inside the microchannel could be obtained. In conclusion, this novel temperature distribution measurement system will be very useful to the accurate analysis of the flow characteristics in the microchannel.

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Effect of Heat Input of Outside Weld on Low Temperature Toughness of Inside Weld for Multiple Electrode SA Welded API 5L X70 with Sour Gas Resistance (내부식용 API 5L X70 다전극 SAW 용접부의 내면 저온인성에 미치는 외면 입열의 영향)

  • An, Hyun-Jun;Lee, Hee-Keun;Park, Young-Gyu;Eun, Seong-Su;Kang, Chung-Yun
    • Journal of Welding and Joining
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    • v.32 no.1
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    • pp.93-101
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    • 2014
  • This study aims to investigate the effect of heat input of outside SAW weld on low temperature toughness($-20^{\circ}C$) of inside SAW weld for API 5L X70 with sour gas resistance. As increasing heat input of the outside weld, low temperature toughness of the inside weld was decreased. Especially, in spite of the same heat input, the value of low temperature toughness was fluctuated. On the basis of fracture and microstructure analysis, the low temperature toughness is correlated with the fracture area ratio of shear lips and four kinds of fracture sections. These sections were divided with size and shape of dimple correlated with grain boundary ferrite and cleavage correlated acicular and polygonal ferrite in grain. Therefore, it was seen that these sections were two of final solidification area in the inside weld and the outside weld, no reheated zone and reheated zone in the inside weld. In conclusion, it is thought that the difference of low temperature toughness at the same heat input is due to the fact that each of impact test specimens could have the different microstructure, even though the notch was machined under the error tolerance of 1mm. It is because the final solidification area of the inside weld is very narrow.

Development the protective clothing for a dropworts cropping workers (미나리 작업자를 위한 작업복 개발에 관한 연구)

  • 최정화;백윤정
    • Journal of the Korean Society of Clothing and Textiles
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    • v.24 no.8
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    • pp.1266-1275
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    • 2000
  • This study was to research the actual condition of a dropworts working environment and to develope the clothing to reduce the work road. The actual conditions of working environment, working position and clothing were surveyed. Experiments were performed in the chamber and in the field. In the chamber, rectal temperature, 11 points skin temperatures(forehead, chest, abdomen, upperarm, forearm, dorsum manus, palm, thigh, calf, dorsum pedis and pelma), heart rates, microclimates inside clothing on the chest and subjective sensations were measured for comparing between 2 different types o garments. In the field, rectal temperature, abodomen skin temperature, 3 points microclimates inside clothing(chest, back and thigh), heart rates, the volume of EMG and subjective sensations were measured. The results were as follows; 1. There were no significant differences in rectal temperature between a old type protective clothing and a new type both in the chamber and the field. 2. Subjects wearing a old type clothing responded \"a little cold\", \"a little uncomfortable\" and subjects wearing a new type protective clothing responded \"normal\", \"comfortable\" both in the chamber and the field. 3. In the field test results, abodemen skin temperature in a old type clothing was higher and microtemperatures inside clothing of chest, back and thigh in a new type protective clothing were higher. 4. The volume of EMG was lower in the new type protective clothing than in the old one.protective clothing than in the old one.

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A Study on Frost Protection Methods for Water Meter in Seoul Area (서울지역의 수도계량기 동파방지방안 연구)

  • Kim, H.I.;Ryu, T.H.;Park, T.J.;Oh, S.Y.;Choi, Y.J.
    • Proceedings of the SAREK Conference
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    • 2007.11a
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    • pp.612-617
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    • 2007
  • Water meter frost in winter is a nuisance to the water administration and citizen as well. It causes stop of water supply, possibility of accident due to leakage freezing, and additional official work to change frost water meters. This study was carried out to give some basic information of water meter frost condition, to verify the effect of frost protection devices such as lagging vinyl cover, electric heater, and meter pit using subterranean heat. Nearly half of the number of the water meter frost happens in old apartment house with outer corridor, and temperature of the meter box was measured in that kind of apartment house, comparing with atmosphere temperature. The capability of three kinds of lagging vinyl cover was investigated by measuring the inside temperature of the insulated box. Also the capability of existing meter pits and new meter pits using subterranean heat was compared by measuring the inside temperature of the pits. One of the result is that the inside temperature of meter pits using subterranean heat was higher than that of the existing ones, and deeper pit causes higher inside temperature in case of using subterranean heat.

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A study on the temperature inside clothing as fundamental data for development of the heat energy harvesting clothing (인체 전력에너지 수확의류 개발을 위한 의복내 온도 측정의 기초적 고찰)

  • Yang, Jin-Hee;Cho, Hyun-Seung;Park, Sun-Hyung;Lee, Joo-Hyeon
    • Science of Emotion and Sensibility
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    • v.16 no.1
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    • pp.125-132
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    • 2013
  • Recently, the consciousness of energy crisis is rapidly growing and sustainable eco-friendly energy sources are becoming issue. Therefore the portable electronic device requires new energy sources for providing continuous power supply and the power energy harvesting system of the human body that enables the power-harvesting research requests anytime, anywhere. One of the sources for energy harvesting is heat energy, which is the difference in temperature of the body and the surrounding environment. We tried to analyze the temperature difference between the environmental temperature and the temperature inside clothing according to the structure of the closed portion. And we examined the temperature difference between the environmental temperature and the temperature inside clothing according to the material of the clothing. The analysis showed that we have been able to get different results at parts of the body in the temperature inside clothing according to the structure of clothing. In upper torso of the chest and back, the temperature inside clothing of 'closed structure' was higher than the temperature inside clothing of 'opened structure'. In the section of arm and leg, it was reduced the difference of temperature inside clothing between 'closed structure' and 'opened structure'. It was particularly noticeable in the section of leg. The results of analysis of the difference between the environmental temperature and the temperature inside clothing according to the material of the clothing, in both cases of the two materials, 'closed structure' was higher than the 'opened structure' in the difference value between the environmental temperature and the temperature inside clothing. There was a difference according to the material in the section of leg. In this study, we outlined the basic guidelines for developing heat energy harvesting clothing by exploring the structure and material of clothing suitable for the heat energy harvesting.

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A Comparative Study Between Linear Regression and Support Vector Regression Model Based on Environmental Factors of a Smart Bee Farm

  • Rahman, A. B. M. Salman;Lee, MyeongBae;Venkatesan, Saravanakumar;Lim, JongHyun;Shin, ChangSun
    • Smart Media Journal
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    • v.11 no.5
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    • pp.38-47
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    • 2022
  • Honey is one of the most significant ingredients in conventional food production in different regions of the world. Honey is commonly used as an ingredient in ethnic food. Beekeeping is performed in various locations as part of the local food culture and an occupation related to pollinator production. It is important to conduct beekeeping so that it generates food culture and helps regulate the regional environment in an integrated manner in preserving and improving local food culture. This study analyzes different types of environmental factors of a smart bee farm. The major goal of this study is to determine the best prediction model between the linear regression model (LM) and the support vector regression model (SVR) based on the environmental factors of a smart bee farm. The performance of prediction models is measured by R2 value, root mean squared error (RMSE), and mean absolute error (MAE). From all analysis reports, the best prediction model is the support vector regression model (SVR) with a low coefficient of variation, and the R2 values for Farm inside temperature, bee box inside temperature, and Farm inside humidity are 0.97, 0.96, and 0.44.

Analysis of the Thermal Environment in the Laying House (산란계사내부 열환경 분석)

  • Kim Y. B.;Lee S. K.;Kim S. T.;La W. J.;Chang H. H.
    • Journal of Animal Environmental Science
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    • v.11 no.3
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    • pp.177-188
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    • 2005
  • In this study, the thermal environmental factors in a layer f(arm such as dry bulb temperature, relative humidity, black globe temperature and illumination intensity were measured and analyzed to serve as basis for effective design and plan of poultry houses. The correlation analysis between the different factors was also done. Heat Index as measure of the thermal stress was also calculated and analyzed. A $1,000m^2$ laying house, 4 meters high with 52,000 layers in six-stage type cages was used in the measurement of the different environmental parameters. The results were as follows; 1. The temperature of the inside air and materials was directly related to the increase in aerial temperature based on the dry-bulb, black globe temperature reading. The correlation factor of the outside to inside air based on dry bulb setting was very significant at 0.927 The dry bulb temperature for inside temperature ranged from $19.9\~28.8^{\circ}C\;with\;SD+2.2^{\circ}C$ while that of the outside air was $16.2\~33.1^{\circ}C,\;SD+3.5^{\circ}C$. In addition, the temperature of the inside air was very stable. 2. The black globe temperature of the inside air ranged from $20.1\~28.8^{\circ}C,\;SD+2.3^{\circ}C$ while that of the outside air was $16.2\~47.5^{\circ}C,\;SD+6.0^{\circ}C$. 3. The relative humidity of the outside and inside air was $72.4\~100\;and\;50.2\~85.6\%$ with an average of $89.2\;and\;71.7\%$, respectively. 4. The illumination intensity in the laying house was less than 7 lux, with an average of $1.2\~2.5lux$ relative to height indicating that the laying house was well isolated from outside radiation. 5. The heat index of the inside air of the laying house had a high variation from $20.5^{\circ}C,\;SD+2.5^{\circ}C$ while that of the outside air was $13.1\~45.5^{\circ}C$, with an average of $21.6^{\circ}C,\;SD+6.3^{\circ}C$.

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Change in the Plant Temperature of Tomato by Fogging and Airflow in Plastic Greenhouse (포그분사 및 공기유동에 의한 온실재배 토마토의 엽온 변화)

  • Nam, Sang-Woon;Kim, Young-Shik;Seo, Dong-Uk
    • Journal of Bio-Environment Control
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    • v.23 no.1
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    • pp.11-18
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    • 2014
  • To investigate the influence of surrounding environment on the plant temperature and examine the effect of plant temperature control by fogging and airflow, plant temperature of tomato, inside and outside air temperature and relative humidity, solar radiation and wind speed were measured and analyzed under various experimental conditions in plastic greenhouse with two-fluid fogging systems and air circulation fans. According to the analysis of plant temperature and the change of inside and outside air temperature in each condition, inside air temperature and plant temperature were significantly higher than outside air temperature in the control and shading condition. However, in the fogging condition, inside air temperature was lower or slightly higher than outside air temperature. It showed that plant temperature could be kept with the temperature similar to or lower than inside air temperature in fogging and airflow condition. To derive the relationship between surrounding environmental factor and plant temperature, we did multiple regression analysis. The optimum regression equation for the temperature difference between plant and air included solar radiation, wind speed and vapor pressure deficit and RMS error was $0.8^{\circ}C$. To investigate whether the fogging and airflow contribute to reduce high temperature stress of plant, photosynthetic rate of tomato leaf was measured under the experimental conditions. Photosynthetic rate was the highest when using both fogging and airflow, and then fogging, airflow and lastly the control. So, we could assume that fogging and airflow can make better effect of plant temperature control to reduce high temperature stress of plant which can increase photosynthetic rate. It showed that the temperature difference between plant and air was highly affected by surrounding environment. Also, we could estimate plant temperature by measuring the surrounding environment, and use it for environment control to reduce the high temperature stress of plant. In addition, by using fogging and airflow, we can decrease temperature difference between plant and air, increase photosynthetic rate, and make proper environment for plants. We could conclude that both fogging and airflow are effective to reduce the high temperature stress of plant.

Variation Profiles of Temperature by Green Area of Apartments in Gangnam, Seoul (서울 강남지역 아파트단지의 녹지면적에 따른 온도변화 모형)

  • 홍석환;이경재
    • Korean Journal of Environment and Ecology
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    • v.18 no.1
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    • pp.53-60
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    • 2004
  • This study was carried out to investigate the effect of green area in apartment complexes to variation of temperature. The inside temperature of each site was estimated by analyzing Landsat ETM+ image data. The factors on variation of temperature were landcover type, building density, and Normalised Difference Vegetation Index(NDVI). The results of correlation between inside temperature of apartment complex and land cover type showed that the green area ratio had negative(-) correlation and impermeable pavement ratio had positive(+) correlation. Building-to-land ratio was not significant with inside temperature. A coefficient of correlation between the temperature value and the value of permeable pavement ratio added up green area ratio was higher than a coefficient of correlation between the temperature value and the value of permeable pavement ratio added up impermeable pavement ratio. Thus we may define that permeable pavement area decrease urban temperature with green area in apartment complex. Floor area ratio had no significant correlation with inside temperature. Inside temperature was decreased as the NDVI was increased. To establish the temperature distribution model in a development apartment complex, As the result of regression analysis between inside temperature as dependent variable and permeable pave ratio+green area ratio, green area ratio, building-to-land ratio and NDIT as independent variables, only permeable pavement ratio added up green area ratio of the independent variables was accepted fur regression equation in both two seasons and adjusted coefficient of determination was 41.4 on September, 2000 and 40.4 on June,2001.