• Title/Summary/Keyword: And temperature

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Estimation of Expected Temperature Using Heat Balance Model and Observation Data

  • Kim, Eun-Byul;Park, Jong-Kil;Jung, Woo-Sik
    • Asian Journal of Atmospheric Environment
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    • v.9 no.3
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    • pp.214-221
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    • 2015
  • This study considers mean skin temperature to calculate expected temperature using the new heat balance model because the skin temperature is the most important element affecting the heat balance outdoors. For this, we measured the skin temperature in high temperature condition of Korea and applied it to calculate the expected temperature. The calculated expected temperature is compared with the result calculated using previous models which use the estimated mean skin temperature by considering metabolic rate only. Results show that the expected temperatures are higher when measured mean skin temperature is applied to the model, compared to the expected temperature calculated by applying mean skin temperature data calculated using metabolic rate like previous models. The observed mean skin temperature was more suitable for outside conditions and expected temperature is underestimated when mean skin temperature calculated by the equation using metabolic rate is used. The model proposed in this study has a few limitations yet, but it can be applied in various ways to facilitate practical responses to extreme heat.

A Study on the Surface Temperature Rise in Spur Gear Part I - Flash Temperature (Spur Gear의 표면온도상승에 관한 연구 Part I - Flash Temperature)

  • 김희진;문석만;김태완;구영필;조용주
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2000.06a
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    • pp.251-257
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    • 2000
  • A numerical simulation of the temperature rise for sliding surface in dry contact is based on Jaeger's formula combined with a calculated heat input. A gear tooth temperature analysis was performed. The pressure distribution has the Hertzian pressure distribution on the heat source. The heat partition factor is calculated along line of action. A Temperature distribution of tooth surface is calculated about before and after profile modification. A Temperature of addendum and deddendum in modified gear have reduced.

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Skin Temperature Responses of Hanbok When It Worn (한복 착용에 따른 피보온의 변화)

  • 송명견;신정화
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.6
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    • pp.763-770
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    • 2002
  • The objective of the study was to investigate skin temperature responses of Hanbok when it was worn. Two healthy females(average 21 years, 155cm and 60kg were exposed to a climatic chamber(Room Temp. $21{\pm}1^{\circ}C,\;52{\pm}2%R.H.$, 0.15m/s). During the experiment, rectal temperature, skin temperature of 9 areas, clothing microclimate, subjective sensation were measured. Chima and Jogory to be made of silk nobang(SN) or Ramie were worn for summer. Polyester(P) Chima and Jogori(R) could be wort for spring and autumn. For winter, silk Chima, Jogori(S) and Durumagi(D) were commonly worn. Rectal temperature was high in order of naked(N), R, SN, P, S, D. However Mean skin temperature was reversely high in order of D, S, SN, R, P, naked. In naked, skin temperature was high in order of head, trunk upper extremity and lower extremity. But on wearing of Hanbok, it was the highest at the chest except head regardless of kinds of clothing ensembles. Skin temperature of upper arm was secondly highest on wearing the silk ensemble and the Durumagi ensemble, but skin temperature of buttock was secondly highest on wearing the silk nobang ensemble and the ramie ensemble. Skin temperature on wearing the silk ensemble was generally higher than those on other clothing ensembles. Local and mean skin temperatures on wearing the silk ensemble and the Durumagj ensemble were generally higher than on other clothing ensembles. Heat resistance of the fabric might have affected on the local skin temperature.

Temperature distribution during heavy oil thermal recovery considering the effect of insulated tubing

  • Zhang, Songting
    • Geomechanics and Engineering
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    • v.19 no.6
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    • pp.523-532
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    • 2019
  • Based on the formation characteristics, wellbore parameters and insulated tubing (IT) parameters of the Shengli oilfield, Shandong, China, a geomechanical model is built to predict the temperature distributions of the wellbore and formation. The effects of the IT heat conductivity coefficient (HCC), well depth and IT joint on the temperature distribution of the IT, completion casing, cement sheath, and formation are investigated. Results show the temperature of the formation around the wellbore has an exponentially decreasing relation with the distance to the wellbore. The temperature of the formation around the wellbore has an inverse relation with the IT HCC when the temperatures of the steam and the formation are given. The temperature of the casing outer wall is mainly determined by the steam temperature and IT HCC rather than by the initial formation temperature. The temperature of the casing at the IT joint is much larger than that of the other location. Due to the IT joint having a small size, the effects of the IT joint on the casing temperature distribution are limited to a small area only.

Correlative Changes between Photosynthetic Activities and Chlorophyll Fluorescence in Wheat Chloroplasts Exposed to High Temperature

  • Young-Nam Hong
    • Journal of Plant Biology
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    • v.37 no.1
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    • pp.37-42
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    • 1994
  • Correlative changes between photosynthetic O2 exchange rates and room temperature Chl fluorescence were investigated in wheat (Triticum aestivum L.) chloroplasts treated with high temperature for 5 min. With increasing treatment temperature, photosynthetic O2 evolution rate mediated by PSII was decreased, showing 50% inhibition at 38$^{\circ}C$ (I50). But PSI activity measured by O2 uptake rates was stimulated as a function of increasing temperature. Dark level fluorescence (Fo)-temperature (T) analysis showed that fluorescence rising temperature (Tr), critical temperature (Tc), and peak temperature (Tp) was 38, 43, and 52$^{\circ}C$, respectively. Quenching analysis of Chl fluorescence showed that both the oxidized fraction of plastoquinone (qQ) and degree of thylakoid membrane energization (qNP) increased up to 4$0^{\circ}C$ and then declined dramatically. These results suggest that Tr is correlated with temperature showing a 50% of inhibition of photosynthesis and under mild high temperature stress, qNP is worth regarding as indicator for heat-induced damage of photosynthesis.

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Temperature Monitoring System of Power MOSFET for IPCM (지능형 전력제어모듈을 위한 온도 모니터링 시스템)

  • Choi Nak-Gwon;Kim Ki-Hyun;Kim Hyoung-Woo;Seo Kil-Soo;Kim Nam-Kun
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.55 no.1
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    • pp.20-25
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    • 2006
  • We suggest a novel temperature detection method utilized in temperature monitoring system. Suggested method detects temperature variation by using $R_{ds(on)}$ characteristics of MOSFET, while conventional methods are using extra devices such as a temperature sensor or an over-temperature detection transistor. For voltage detection between drain and source, 10 bits resolution ADC is needed. Therefore possible measurement signal range is about ten mV. If detected temperature's voltage exceed protection temperature's voltage then controller generates OT (Over Temperature) signal to stop MOSFET's trigger signal. Whole process of measurement is controlled by software. Experimental results show that the developed temperature monitoring system can provide the suitable temperature monitoring method and difference between detected and data sheet value of the suggested system is about $3\%$.

A Comparison Study on the Skin Temperature on the Adult Male. Female at Environmental Temperature (각 환경기온하에서의 성인 남 . 여자의 피부온 비교)

  • 심부자
    • Proceedings of the ESK Conference
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    • 1997.04a
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    • pp.227-246
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    • 1997
  • With a view of to providing basic data for designing male's and female's clothes, heslthy males and females(five each) were exposed to three different environmental temperature( $20{\pm}1.0^{\circ}C$ $28{\pm}1.0^{\circ}C$,$32{\pm}1.0^{\circ}C$ in the nude. Their adaptation of skin temperature, physilogical responses, oral temperature, blood pressure, pulse rates) and psychological reactions (thermal, comfort and perceptive sweat sensations) were analyzed to be as follows; The subjects's skin temperature had a similar look of adaptation, but the stability of skin temperature differed at the $20{\pm}1.0^{\circ}C$and at the $28{\pm}1.0^{\circ}C$ Males had higher skin temperatures at three environmental temperatures, but females showed a higher temperature change at the $20{\pm}1.0^{\circ}C$ and$28{\pm}1.0^{\circ}C$ and males at the $32{\pm}1.0^{\circ}C$ Thus females were more resistant to the cold, while male were more resistant to the heat. As environmental temperature increased, oral temperature and pulse rates also grew up. Females turned higher in oral temperature and lower in blood pressure, but both sexes had a normal range of physiological reactions. Even though three environmental temperature were same changes in thermal sensation at and in perceptive sweat sensation at $28{\pm}1.0^{\circ}C$and in perceptive sweat sensation at$32{\pm}1.0^{\circ}C$ the two sexes had the same response in comfort sensation at the three environmental temperature.

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Seasonal Variations of Stream Water Temperature and its Affecting Factors on Mountain Areas (산지계류의 계절적 수온변동 특성 및 영향인자 분석)

  • Nam, Sooyoun;Choi, Hyung Tae;Lim, Honggeun
    • Journal of Korean Society on Water Environment
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    • v.35 no.4
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    • pp.308-315
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    • 2019
  • The objective of this study was to investigate mountain stream water and air temperatures, area, latitude, altitude, and forest coverage in headwater catchments located in Kangwon-do, Mid-eastern Korea from 2015 to 2017. Daily mean value of mountain stream water temperature was approximately $6^{\circ}C$ lower than the daily mean value of air temperature on the monitoring sites during the observation period. Monthly mean value of mountain stream water temperature increased with increasing monthly mean value of air temperature from May to August during the observation period. Seasonal variations of mountain stream water temperature were dependent on air temperature rising and falling periods. Correlation analysis was conducted on mountain stream water temperature to investigate its relationship with air temperature, area, latitude, altitude, and forest coverage of air temperature rising and falling periods. The correlation analysis showed that there exists a relationship (Correlation coefficient: -0.581 ~ 0.825; p<0.05), particularly the air temperature showed highest correlation with mountain stream water temperature. Regression equations could be developed due to contribution of air temperature to affect mountain stream water temperature (Correlation coefficient: 0.742 and 0.825; p<0.01). Therefore, a method using various parameters based on air temperature rising and falling periods, could be recommended for predicting mountain stream water temperature.

Assessment of Degradation Rate Coefficient and Temperature Correction Factor by Seasonal Variation of Concentration and Temperature in Livestock Wastewater Treatment in Field Scale (현장수준의 축산폐수처리에 있어서 계절별 농도 및 온도변화에 따른 분해반응계수 및 온도보정계수의 산정)

  • 박석환
    • Journal of Environmental Health Sciences
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    • v.22 no.2
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    • pp.90-95
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    • 1996
  • This study was performed to calculate the degration rate coefficient, operating parameters to meet the effluent standards, and the temperature adjustment coefficients to each parameter of pollution by seasonal variation of concentration and temperature of influent in livestock wastewater treatment by sequencing batch reactor process in field scale. The followings are the conclusions that were derived from this study. 1. In the field, temperature of livestock wastewater in reactor was 20.3$\circ$C in summer and 6.0$\circ$C in winter. The ratio of BOD:TKN: T-P in influent was 100:80:7. BOD loadings in winter and spring were 0.26 and 0.43 kg $BOD/m^3$ day, respectively. Those in summer and fall were 0.25 and 0.13 kg $BOD/m^3$ day, respectively. 2. The degradation rate coefficient for TKN was larger in summer and fall in which temperature was high than that in which temperature was high than that in winter and spring in which concentration was high. On the contrary, the phosphorus uptake rate was larger in winter and spring than that in summer and fall. 3. The hydraulic retention time in winter and spring was longer than that in summer and fall. Especially, in order to meet the standard for TKN of 120 mg/l in winter in which temperature of wastewater was 6.0$\circ$C, as the MLSS concentration was increased from 4, 000 to 7, 000 mg/l, the hydraulic retention time was increased from 212 to 121 hours. But, in order to shorten that less than 121 hours for the economical wastewater treatment, countermeasure to increase temperature of wastewater in the reactor should be considered. 4. the temperature adjustment coefficients for BOD, $COD_{Mn}$, TKN and T-P were 1.0241, 1.0225, 1.0541 and 1.0495, respectively. Namely, the treatment of TKN was most sensitively affected by temperature. For the purpose of the effective removal of nitrogen and phosphorus which are sensitive to temperature, it is necessary to keep the temperature of livestock wastewater more than 20$\circ$C which is the temperature of it in summer.

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The Bias Drift Due to Fiber Coil Temperature Variation and the Temperature Compensation in Fiber Optic Gyroscope (광섬유자이로의 고리 온도변화에 의한 바이어스 특성 및 온도 보상)

  • Jo, Min-Sik;Chong, Kyoung-Ho;Do, Jae-Chul;Choi, Woo-Seok;Song, Ki-Won;Kang, Su-Bong;Shin, Won-Chul
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.2
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    • pp.222-227
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    • 2009
  • The bias characteristics due to the changes of temperature and temperature gradient of fiber coil are investigated in fiber-optic gyroscope. The bias performance is degraded with the changes of temperature and temperature gradient of fiber coil. The temperature compensation using both the temperature-dependent bias measurement and the temperature-induced error model of fiber-optic gyroscope improves the bias stability about 3 times as much as the uncompensated original case, which leads to very stable bias performance over the temperature range from $-35^{\circ}C$ to $+77^{\circ}C$.