• Nuclear Engineering and Technology
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• v.26 no.4
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• pp.570-577
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• 1994

The loss of water in the carbon steel balls and water region of the end shield for CANDU 6 reactor could lead to significant temperature gradient through the end shield structure which amy result in the excessive deformation. With an assumed end shield drained scenario, the heat deposition rates were calculated through the end shield associated with the central fuel channel during full power operation as an initial step to thermal stress analysis. The drained case was compared with that of water present normal case in therms of heat deposition rater and the total heating throughout the end shield regions. The compared results show that the heat deposition and the total heating remain almost the same between the two cases. It was found that the change of volume integrated flux in the end shield regions due to the loss of water contribute a negligible effect on the heat deposition in this region.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.17 no.3
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• pp.304-313
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• 2010

Purpose: The purpose of this study was to examine preventive effects of water drinking on postprandial fall of blood pressure in the elderly. Method: Participants were 25 elders who had experienced postprandial fall of systolic blood pressure of more than 15mmHg in a previous study. Within subject repeated measures design using random order allocation was used to control extraneous variables among participants. During the experiment, each participant had to drink 400mL water before lunch, whereas when in the control, they only had their lunch. Blood pressure and heart rate were measured for both times before lunch and at 15 minutes intervals up to 90 minutes after lunch. Data were analyzed using descriptive statistics, repeated measures of ANOVA, paired t-test and Bonferroni adjustment as Post-hoc analysis. Results: Water drinking before lunch elicited significant pressor effects by increasing systolic and diastolic pressure $13.9{\pm}4.7/5.2{\pm}2.2mmHg$ compared blood pressure during the control p<.005, p<.022. Heart rate, however, did not change significantly at either time. Conclusion: Drinking water before meal is recommended for elders who experience postprandial hypotension. However, the appropriate volume of water to prevent postprandial fall in blood pressure should be further studied.

• Biomolecules & Therapeutics
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• v.8 no.2
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• pp.132-139
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• 2000

This study was performed far investigation of influence on renal function of idazoxan, $\alpha_{2}$-adrenergic antagonist, using the dog. Idazoxan, when giver. into vein, produced the decrease of urine volume(vol) accompanied with the reduction of free water clearance($C_{H2O}$), amounts of sodium excreted in urine($E_{Na}$), with the increase of potassium excreted in urine($E_{K}$), and so ratios of potassium against sodium($K^{+}/Na^{+}$) were elevated, at this time, greatened reabsorption rate of sodium and diministered that of potassium in renal tubules were appeared. Idazoxan administered into a renal artery elicited the augmentation of vol, glomerular filtration rate(GFR), renal plasma flow(RPF) and no change of filtration fraction(FF) in only ipsilateral kidney, whereas $E_{Na},\;E_{K}\;and\;K^{+}/Na^{+}$ were increased and $C_{H2O}$ was decreased in both control and experimental kidney. Idazoxan given into carotid artery showed partial increased vol, remarkable expanded RPF and unchanged GFR, and so filtration fraction(FF) was markedly reduced. Above results suggest that anti- diuretic action of idazoxan given into vein is mediated by reduction of $C_{H2O}\;and\;E_{Na}$, diuretic action only in the ipsilateral kidney by idazoxan given into a renal artery is caused by hemodynamic improvement through expansion of vas afferens in glomeruli.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.1
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• pp.82-91
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• 1997

R-410a and R-407c witch have the best potential among the substances being considered as R-22 alternatives were tested as "drop in" refrigerants against a set R-22 baseline tests for comparison. The performance evaluations were carried out in a psychrometric calorimeter test facility using the residential split-type air conditioner under the ARI rating conditions. Other than the use of different lubricant and a hand-operated expansion valve, one of the commercial systems was selected for the experiment. Performance characteristics were measured; compressor power, capacity, VCR, mass flow rate and COP. The tests showed that R-407c can be directly applied to the existing refrigeration system because of its similar vapor pressure and other thermopysical properties with those of R-22. However, it required change to the volume flow rate of compressor in order to achieve the similar performance with R-22 because of its relatively small VCR and capacity. Meanwhile, R-410a has too high a vapor pressure to be applied to the existing system and this feature results in relatively low COP of the system compared to that of R-22. But this could be improved by changing compressor design considering R-410a's relatively high VCR and capacity compared to those of R-22.

• Journal of Chest Surgery
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• v.17 no.3
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• pp.418-423
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• 1984

Appreciation of the large volume deficits which may occur in surgical or trauma patients due to blood loss has led to vigorous transfusion techniques designed to overt hypovolemic shock and ischemic damage to vital organs which may develop in minutes during the hypovolemic state. In a significant proportion of patients treated with massive rapid blood or fluid transfusion, hypervolemia occurs and life threatening pulmonary edema may develop. Especially, hypervolemia may occur during transfusion for preventing development of the so-called low output syndrome following cardiac surgery. However, the most effective indicator which reveals the adequate level of transfusion is not settled yet. The present study was aimed to compare the effectiveness of the indicators suggested thus far and to determine the most sensitive one. Eight dogs were experimentally studied in terms of left atrial pressure, pulmonary arterial systolic pressure, central venous pressure, mean systemic arterial pressure and heart rate before and after induced hypervolemia with infusion of 600ml heparinized homologous blood. Immediately after induced overtransfusion of the blood, pulmonary arterial systolic pressure increased 75.0%, in omparison with the control before transfusion, left atrial pressure 58.8%, central venous pressure 44.6%, and mean systemic arterial pressure 10.1%, one hour after transfusion, pulmonary arterial systolic pressure 40.0%, left atrial pressure 21.2%, central venous pressure 14.5%, and mean systemic arterial pressure 3.2%, central venous pressure 14.5%, and mean systemic arterial pressure 3.2%, respectively. Heart rate showed no significant change throughout the experiment. These result suggested that the changes of the pulmonary arterial systolic pressure is the most sensitive indicator for detection of hypervolemia during blood transfusion.

• International Journal of Air-Conditioning and Refrigeration
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• v.6
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• pp.36-44
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• 1998

R-410a and R-407c which have the best potential among R-22 alternatives were tested as drop-in refrigerants against a set of R-22 baseline tests. The performance evaluations were carried out in a psychometric calorimeter test facility using the residential spilt type air conditioner under the ARI rating conditions. Except the lubricant and hand-operated expansion valve, the other parts of the air conditioner were the same with the commercial system. Performance characteristics were measured; compressor power, capacity, VCR, mass flow rate and COP. The tests showed that R-407c can be directly charged into the current refrigeration system because its vapor pressure and other thermochemical properties are similar to those of R-22. However, it is required to change the volume flow rate of compressor in order to achieve the volumetric capacity of R-22. This results from its relatively small VCR and capacity. Meanwhile, R-410a has vapor pressure values too high to be substituted for the current system and this resulted relatively low COP of R-410a compared to that of R-22.

• Transactions on Electrical and Electronic Materials
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• v.17 no.3
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• pp.146-149
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• 2016

The CrN/TiN/Al thin films for solar selective absorber were prepared by dc reactive magnetron sputtering with multi targets. The binary nitride CrN layer deposited with change in N₂ gas flow rates. The gas mixture of Ar and N2 was an important parameter during sputtering deposition because the metal volume fraction (MVF) was controlled by the N2 gas flow rate. In this study, the crystallinity and surface properties of the CrN/TiN/Al thin films were estimated by X-ray diffraction (XRD), atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM). The composition and depth profile of thin films were investigated using Auger electron spectroscopy (AES). The absorptance and reflectance with wavelength spectrum were recorded by UV-Vis-NIR spectrophotometry at a range of 300~1,100 nm.

• Ecology and Resilient Infrastructure
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• v.3 no.2
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• pp.126-129
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• 2016

The risk of flooding and groundwater depletion is increasing due to the increase of impervious area in an urban area that reduces the volume of infiltration and increases the outflow of rainwater. The objective of this study is to examine the impact of installation of roadside tree protectors with infiltration pipes in terms of the change of the infiltration rate. Through this study, it has been attested that roadside tree protectors with infiltration pipes increased the infiltration rate and decreased water level on the ground, and could be applied in an urban area as the low impact development (LID) facilities.

• Journal of the Korean Society for Heat Treatment
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• v.13 no.4
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• pp.265-271
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• 2000

The microstructural change and transformation characteristics with cooling rate i.e. wheel speed were investigated in 82.8wt%Cu-12.8wt%Al-4.3wt%Ni SMA ribbons fabricated by melt-spinning. The thickness and width of ribbon were decreased with increasing wheel speed, while the uniformity of it was improved. At same wheel speed, the grain size of the contact surface of ribbon was smaller than that of free surface. The mean grain size was decreased with increasing wheel speed, resulted in obtaining grains with $3{\mu}m$ in mean diameter in the wheel speed of 30 m/s. However, micro-voids and cracks at grain boundary could be observed at higher wheel speed. $M_s$ and $A_s$ temperatures were decreased, and $M_s{\sim}M_f$ and $A_s{\sim}A_f$ temperature ranges were broadened with increasing wheel speed. All the ribbons were retained the ordered $D0_3$ due to rapid cooling, the volume fraction of it was increased with increasing wheel speed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.3
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• pp.137-140
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• 2014

With the recent advent of through silicon via (TSV) technology, wafer level-TSV interconnection become feasible in high volume manufacturing. To increase the manufacturing productivity, it is required to develop equipment for backside passivation layer deposition for TSV wafer bonding process with high deposition rate and low film stress. In this research, we investigated the relationship between process parameters and the induced wafer stress of PECVD silicon nitride film on 300 mm wafers employing statistical and artificial intelligence modeling. We found that the film stress increases with increased RF power, but the pressure has inversely proportional to the stress. It is also observed that no significant stress change is observed when the gas flow rate is low.