• Child Health Nursing Research
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• 제18권4호
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• pp.201-206
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• 2012

Purpose: In this study changes were observed in body temperature, heart rate and arterial oxygen saturation (SaO2) of newborns after bathing and to determine the effects of covering their heads with cotton hats after bathing. Methods: Participants were 58 newborn infants, 31 in the experimental group had their heads covered with cotton hats after their bath while 27 in the control group did not. Body temperature, arterial oxygen saturation and heart rate were measured at 8 consecutive times after bathing. Data were analyzed using t-test and repeated measures ANOVA. Results: Body temperature declined shortly after bathing. The experimental group showed faster recovery (p<.001). Heart rate increased after bathing in both groups. Heart rate in the experimental group decreased for 120 minutes and gradually increased to baseline (p<.001). In the control group, heart rate decreased for 180 minutes and then increased but did not reach the baseline (p<.001). Arterial oxygen saturation decreased shortly after bathing and recovery to the baseline was more rapid in the experimental group (30 minutes vs. 60 minutes) (p<.001). Conclusion: With significant changes observed in newborns' body temperature, arterial oxygen saturation and heart rate, covering the head right after bathing is effective in stabilizing infants' physiological system.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1243-1249
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• 2004

This study is focused on the comparison between the internal saturation temperature of the working fluid and the surface temperature of adiabatic zone of two-phase closed thermosyphons with various helical grooves. Distilled water, methanol and ethanol have been used as the working fluid. In the present work, a copper tube of the length of 1200mm and 14.28mm of inside diameter is used as the container of the thermosyphon. Each of the evaporator and the condenser section has a length of 550mm, while the remaining part of the thermosyphon tube is adiabatic section. A experimental study was carried out for analyzing the performances of having 50, 60, 70, 80, 90 helical grooves. A plain thermosyphon having the same inner and outer diameter as the grooved thermosyphons is also tested for the comparison. The results show that the numbers of grooves and the type of working fluids are very important factors for the operation of thermosyphons. A good agreement between the internal saturation temperature of working fluid and the surface temperature of adiabatic zone of two-phase closed thermosyphons with various helical grooves is obtained.

• Bulletin of the Korean Chemical Society
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• 제29권3호
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• pp.555-561
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• 2008

In air stripping of ammonia from the aqueous solution, a new removal model was presented considering the equilibrium principles for the ammonia in aqueous solution and between the aqueous and air phase. The effects of pH, temperature and airflow rate on the ammonia removal were evaluated with the model. In addition, the saturation degree of ammonia in air was defined and used to evaluate the effect of each experimental factor on the removal rate. As pH (8.9 to 11.9) or temperature (20 to 50 oC) was increased, the overall removal rate constants in all cases were appeared to be increased. Our presented model shows that the degrees of saturation were about the same (0.45) in all cases when the airflow condition remains the same. This result indicates that the effect of pH and temperature were directly taken into consideration in the model equation. As the airflow increases, the overall removal rate constants were increased in all cases as expected. However, the saturation degree was exponentially decreased with increasing the airflow rate in the air phase (or above-surface) aeration. In the subsurface aeration the saturation degree remains a constant value of 0.65 even though the airflow rate was increased. These results indicate that the degree of saturation is affected mainly by the turbulence of the aqueous solution and remains the same above a certain airflow rate.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3685-3693
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• 2021

This paper presents a disturbance observer-based robust backstepping load-following control (DO-RBLFC) scheme for modular high-temperature gas-cooled reactors (MHTGRs) in the presence of actuator saturation and disturbances. Based on reactor kinetics and temperature reactivity feedback, the mathematical model of the MHTGR is first established. After that, a DO is constructed to estimate the unknown compound disturbances including model uncertainties, external disturbances, and unmeasured states. Besides, the actuator saturation is compensated by employing an auxiliary function in this paper. With the help of the DO, a robust load-following controller is developed via the backstepping technique to improve the load-following performance of the MHTGR subject to disturbances. At last, simulation and comparison results verify that the proposed DO-RBLFC scheme offers higher load-following accuracy, better disturbances rejection capability, and lower control rod speed than a PID controller, a conventional backstepping controller, and a disturbance observer-based adaptive sliding mode controller.

• 여성건강간호학회지
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• 제15권1호
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• pp.32-42
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• 2009

Purpose: This study was done to examine the effects of abdominal breathing on VAS-Anxiety (VAS-A), blood pressure, peripheral skin temperature and saturation oxygen in pregnant women in preterm labor. Method: The study design was a matched control group interrupted time series. Forty-six women matched to gestational age were assigned to either the experimental group (26) or control group (20). Data were collected between March 2007 and May 2008. For the experimental treatment the women performed abdominal breathing 30 times, which took 5 minutes, and did one set of 5-minute abdominal breathing daily for three days. Data collection was done before and after the abdominal breathing to measure VAS-A, blood pressure, peripheral skin temperature and oxygen saturation. Descriptive, $X^2$, Mann-Whitney U tests were used to analyze the data with the SPSS/PC+Win 15.0 program. Result: For the experimental group there were significant decreases in VAS-A (Z=-4.37, p=.00), systolic blood pressure (Z=-3.38, p=.00), and an increase in skin temperature (Z=-4.50, p=.00) and oxygen saturation (Z=-3.66, p=.00). Conclusion: These findings suggest that abdominal breathing in pregnant women in preterm labor results in decreases in anxiety(VAS-A) including biological evidences such as systolic blood pressure, and increases in peripheral skin temperature and oxygen saturation. Further longitudinal study is needed on the lasting effects and obstetric and neonatal outcomes following abdominal breathing.

• 한국가스학회지
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• 제22권1호
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• pp.1-8
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• 2018

수소연료전지 자동차 압력 용기에는 연료전지 스택으로 수소의 흐름을 제어하기 위해 전자 밸브가 부착되고 있다. 전자 밸브의 솔레노이드는 전기 신호에 의해 유로를 개폐하는 역할을 하며, 전원이 인가되는 시간이 경과함에 따라 온도가 상승하여 일정 온도에서 포화된다. 특히 온도의 상승은 솔레노이드의 흡인력을 감소시키므로 안정적인 수소 공급을 위해서 설계 시 포화 온도와 온도에 따른 흡인력 특성 파악이 요구된다. 본 연구에서는 솔레노이드 설계 변수에 따른 포화 온도 계산식을 제안하고 열 유동 해석을 통해 타당성을 확인하였다. 또한, 온도에 따른 흡인력 변화를 분석하기 위해 전자기장 해석을 수행하였으며 온도 특성 실험을 통해 포화 온도와 흡인력 해석 결과를 검증하였다. 포화온도는 계산식과 해석결과를 비교하였을 때 $5.3^{\circ}C$, 해석 결과와 실험 결과를 비교하였을 때 $5.9^{\circ}C$의 오차가 발생하였으며, 흡인력은 1.0 N, 최대 2.1 N의 오차가 발생하였다.

• 한국자기학회지
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• 제2권3호
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• pp.211-215
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• 1992

The temperature-dependent saturation magnetization curves of amorphous $Fe_{80-x}Co_xB_{20}$ (8 ${\le}$ x ${\le}$ 40, the step of x is 8) alloys were measured using a vibrating sample magnetometer from 77 K up to 1000 K. Curie temperature and the Bloch coefficient were estimated from the saturation magnetization curves. The low temperature dependence of magnetization is in good agreement with Bloch relation, $M_s(T)$=$M_s(O)$ (1-$BT^{3/2}$ - ${\cdots}.$). The spin wave stiffness constant, tne range of the exchange interaction, and the probable atomic spin were calculated from the saturation magnetization values.

• 한국약용작물학회지
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• 제9권3호
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• pp.232-237
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• 2001

본 연구는 야콘의 광합성 효율증진을 위한 기상환경 조건을 규명하여 재배적지의 선정과 재배관리에 대한 기초적 자료를 제공하고자 광도와 온도, 그리고 $CO_2$의 농도에 대한 광합성과 증산량을 조사하였다. 광 보상점은 ${58\;{\mu}mol\;m^{-2}\;s^{-1}}$이었고, 포화점은 ${1708\;{\mu}mol\;m^{-2}\;s^{-1}}$이었다, 증산량은 광도가 증가할수록 높아져 광도 ${2193\;{\mu}mol\;m^{-2}\;s^{-1}}$에서 약 4 mmol ${m^{-2}\;s^{-1}}$간에 이르렀다. 광합성의 최적온도는 ${24^{\circ}C}$였으며, 온도의 변화에 의하여 증산량이 4 mmol ${m^{-2}\;s^{-1}}$에서 8 mmol ${m^{-2}\;s^{-1}}$까지 증가하였을 때 광합성은 오히려 감소하는 경향이었다. 이산화탄소 보상점은 63 mol mol ${m^{-2}\;s^{-1}}$이었고, 포화점은 1155 vpm이었으며, 이산화탄소 농도가 350vpm에서 1300vpm까지 증가함에 따라 광포화점은 높아졌다.

• 한국농공학회지
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• 제42권4호
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• pp.59-66
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• 2000

This study was carried out to investigated the water requirement of twisted sweet peppers which are cultivated in a green house. The meteorological conditions during the experiment period was close to that of normal year except the temperature and relative humidity. The growth status was improved with the increased saturation ratio. The range of the variation of daily water requirement were very large. The peak consumption occurred in the early August. And the higher saturation ratio resulted in higher water requirement. The total water requirement were about 57.180g/d/plant for pot with 100% (P100) of saturation , about 38.700g/d/plant for pot with 80%(P80) of saturation , about 23,720g/d/plant for pot with 60%(P60) of saturation, and about 53, 390g/d/plant for field cultivation in the green house, respectively. The water requirement was correlated with average ambient temperature and growing status, while no significant correlation were found between water requirement and minimum relative humidity or intensity of solar radiation. And the higher correlation was shown as the saturation ratio was increased. The transpiration coefficients of twisted sweet pepper were 378.0g/g for field cultivation in the green house, 363.3g/g for P100, 338.7g for P80 which was the smallest among pot cultivation , and 472.1g/g for P60 , respectively.

• Journal of Magnetics
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• 제20권4호
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• pp.421-426
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• 2015

This paper presents a practical method for estimation of average temperature in the permanent magnet (PM) of electric machine by using finite element analysis (FEA) and dynamo load experiment. First of all, the temperature effect of PM to the torque has been employed by FEA in order to evaluate the Temperature-Torque characteristic curve. The 1st order polynomial equation which is torque attenuation coefficient is derived by the FEA result of the Temperature-Torque curve. Next, torque saturation test with constant current condition is performed by dynamo load experiment. Then, the temperature trend can be estimated by adding the initial starting temperature using the torque attenuation coefficient and torque saturation curve. Lastly, estimated temperature is validated by infrared thermometer which measures temperature of PM surface. The comparison between the estimated result and experimental result gives a good agreement within a deviation of maximum $8^{\circ}C$.