• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.2
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• pp.183-189
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• 2012

Most of the domestic residential buildings have used the traditional radiant heating system, circulating hot water through the cross-linked polyethylene(PE-X) pipe buried in the floor panel of the heating space. New type of the heating panel was recently developed using heat pipes with double wicks. Some experiments were carried out in this study to verify the thermal characteristics of this heating system at the unit heating space which surrounded by outer space whose temperature of air be maintained scheduled value with time. Through the various experiments with several parameters, such as flow rate, inlet and outlet temperatures of hot water and the heating duration and so on, we found that the floor heating system with heat pipes was able to reduce the pumping power for hot water circulation by 4~31% compared with the conventional panel heating system using PE-X pipe. These results could be used for optimal design and efficient operation of the heating system as well as improvement of thermal comfort.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.9
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• pp.527-535
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• 2009

The aim of this study is to investigate the daily heating performance of ground source multi-heat pump system with vertical single U-tube type GLHXs, which were installed in a school building located in Cheonan. Daily average COP of heat pump unit on Jan. 12th, 2009 at heating mode was lower than it on Nov. 10th, 2008 and Dec. 15th, 2008, because of lower EWT of the outdoor heat exchanger and relatively smaller size of condenser and evaporator. But, the system COP on the former was higher than it on the latter because ground loop circulating pump was operated in rated speed. It is suggested that the new algorithms to control the flow rate of secondary fluid for GLHX according to load change have to be developed in order to enhance the performance of the system COP.

• Journal of Chest Surgery
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• v.13 no.2
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• pp.85-91
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• 1980

Extracorporeal circulation by hemodilution technique has been currently used with its clinical safety and good peripheral tissue perfusion in open heart surgery. There is no doubt that $O_{2}$ carrying capacity of the blood is disturbed by decreased hemoglobin level resulting from hemodilution of the circulating blood. From the view point of the blood gas exchange, these experimental studies were undertaken to determined the sate limit of hemodilution in the condition of cardiopulmonary bypass with a constant perfusion flow rate. Twelve adult mongrel dogs weighing 10 to 13 Kg. were anesthetized with pentobarbital and then respiration was controlled with Harvard volume respirator using room air. The cardiopulmonary by pass was performed by use of Sarns heart lung machine (console 5000, 5 head and 2 roller pumps) and Travenol pediatric bubble oxygenator. The perfusion rate during bypass was maintained at a constant rate of 80 ml/min/Kg of body weight. The ratio of oxygen gas flow to blood flow was kept in 3 to 1 constantly. International hemodilution was attained by serial blood withdrawals and immediate infusion of equal volumes of diluants composed of Ringer's lactate, 5% dextrose in water and 25% mannitol solution, proportionally 60%, 30%, and 10%. Arterial and venous blood samples were obtained between 15 and 20 minutes following each hemodilution. Hematocrits and hemoglobin values, $PO_{2}$, $PCO_{2}$ and pH were measured. Oxygen and carbon dioxide contents oxygen consumption and carbon dioxide elimination were calculated groups according to different hematocrit values and the correlations were evaluated. Result were as follows. 1. the arterial $O_{2}$ tension and $O_{2}$ saturation were maintained at the physiological level irrespective of the hematocrit value. 2. The venous $O_{2}$ tension and $O_{2}$ saturation showed a tendency to decline with the decrease in hematocrit value and positive correlation between them (r = +0.49, r = +0.76), The mean values of venous $O_{2}$ tension and $O_{2}$ saturation, however, were not decreased when the hematocrit levels were lower than 20%. 3. The arterial $O_{2}$ content declined lineally in proportion to the fall of hematocrit level with a positive correlation between them (r = +0.95). 4. The venous $O_{2}$ contents were decreased gradually as the hematocrit value decreased with positive correlation between them ( r =+0.89). The trend of diminution of venous $O_{2}$ content, however, was became low according to progressive decrease of hematocrit level. 5. Systemic oxygen consumption was in higher range than $O_{2}$ requirement of basal metabolism when the hematocrit value was above 20%, but abruptly decreased when the hematocrit value became to below 20%. 6. The arterial $CO_{2}$ tension and $CO_{2}$ content showed trend of increasing with progressive decrease of hematocrit value but exhibited a rather broad range and there was no relationship between those value and the hematocrit value. 7. The venous $CO_{2}$ tension and $CO_{2}$ content have also no correlation with change of Ht. value but related directly to those value of arterial blood with positive correlation between them (r = +0.78, r = +0.95_. 8. A-V difference of $CO_{2}$ content and $CO_{2}$ elimination wasnot significantly influenced by Ht. value. From the results, we obtained that feasible limit in inteneional hemodilution is above the hematocrit value of 20% under the given experimental condition.

• The Journal of Dong Guk Oriental Medicine
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• v.1
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• pp.55-80
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• 1992

In order to examine that the effect of Sam Hwa San, circulating the vital energy of Sam Cho and controlling body fluid metabolism, gives any influence on renal function, changes in the urine flow, eletrolytes excretion, plasma aldosterone concentration and renin activity were observed after intravenous infusion of the Sam Hwa San extract in rabbit. Also in vitro effect of the herb extract on oxygen consumption in renal cortical slices and ATPase activity in kidney microsomes was measured. The following results were obtained : 1. The urine flow was markedly increased at 10 min after intravenous infusion of the Sam Hwa San extract($0.134{\pm}0.015$ vs. $0.433{\pm}0.046ml/min.kg$), but return ed to normal value after 40 min of infusion. 2. The glomerular filtration rate was significantly increased at 10 min after in travenous infusion of the Sam Hwa San extract, and the renal plasma flow at 10 and 20 min after infusion of the Sam Hwa San extract, following return to normal value. 3. $Na^+$ excretion was significantly increased during 10-40 min after intravenous infusion of the Sam Hwa San extract, although showed the maximal rate at 10-20 min. The fractional $Na^+$ excretion was also increased during 10-40 min. $K^+$ excretion was rapidly increased at 10 min after the intravenous Infusion of the Sam Hwa San extract and then gradually decreased to normal level at 40 min. The fractional $K^+$ excretion was significantly increased during 10-40 min after the intravenous infusion of the Sam Hwa San extract. 4. The plasma aldosterone concentration and renin activity were not altered by the infusion of the Sam Hwa San extract. 5. The ouabain-sensitive oxygen consumption of renal cortical slices was significantly reduced by the Sam Hwa San extract(0.5 and 1.0 vol.%). 6. The Na-K-ATPase activity of renal microsomes was strongly inhibited by the Sam Hwa San extract(0.5 and 1.0 vol.%). These results suggest that the Sam Hwa San causes a strong diuretic effect which results from reduction of Na reabsorption in renal tubule by a direct inhibition of Na-pump and, in part, from all increase in renal blood flow. In clinic, it is considered to obtain the therapeutic effect in body fluid metabolism disharmony to cause the circular disorder of vital energy.

• Journal of the Korean Ceramic Society
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• v.50 no.1
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• pp.18-24
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• 2013

This study was conducted to recycle fly ash containing an abundance of CaO generated from combustion in a circulating layer as a carbon storage medium. The study utilized XRD, TG-DTA and XRF analyses during the hydration of fly ash and identified calcium substances within fly ash that could be used in a carbonation process. $Ca^{2+}$ ions in the calcium substances were easily converted to hydrates. A carbonation experiment was done, which used the method of $CO_2$ gas injection to produce suspensions by mixing fly ash with distilled water. The results were analyzed using TG-DTA, XRD, and pH meter measurements. The study was able to verify that the reaction was completed at a $CO_2$ flow rate of 300cc/min approximately 30 minutes after an injection into a solution with a solid-liquid ratio of 1 : 10 of fly ash and distilled water. Moreover, the stirring time of the suspensions did not influence the reaction, and the reaction time was found to diminish as the portion of the fly ash became smaller. Thus, this study produced carbon storage fly ash having a $CO_2$ storage rate of about 71% through the utilization of the CaO content contained within fly ash.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.29 no.3
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• pp.200-213
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• 1993

A model experiment on a midwater rope trawl net which is used in the North Pacific to catch alaska pollack is carried out in the circulating tank to examine the basic efficiency of the net. The prototype is the net used by M/S Hanil(1, 179GT, 2, 700PS), a Korean trawler. The model net was made according to the Tauti's Similarity Law of Fishing Gear in 1/100 scale by considering the condition of the tank. To measure the basic efficiency of the standard model net, the vertical opening and width between some points marked on the net were measured, and the hydrodynamic resistance were determined. Then the constructive conditions of the net were varied as follows and the factors were measured again to compare the efficiency of those nets with that of the standard net(A-1 type) front weight multiplied 1.5 times: A-2 type. buoyancy and depressing force multiplied 1.7 times: A-3 type. front weight multiplied 1.5 times on A-3 type: A-4 type. depressors rigged at ground rope: B type. cod-end stuffed with cashmylon wad: C type. The results obtained can be summarized as follows: 1. The vertical opening at the center of head rope was steeply decreased with the flow velocity increasing and the vertical opening H(m) can be expressed in H=1.2v super(-1.2)(v : flow velocity in m/sec). The width of the net varied a little when the flow velocity was over 0.4m/sec, and the width of net mouth showed about 37% of the distance between the fore tips of net pendant. The shape of net mouth was almost a circle at 0.2m/sec and then steeply flatted elliptically with the flow velocity increasing and the area of mouth S(m super(2)) can be expressed in S=(1.65-2.3v)$\times$10 super(-2). The hydrodynamic resistance of the net increased almost linearly with the flow velocity increasing and the resistance R(kg) can be expressed in R=3.2$\times$d/l$\times$abv. where d/l denotes the mean of d(diameter of netting twine) and l(length of a leg in a mesh) from wing tip to the end of bag-net except cod-end on the side pannel, and a denotes the strectched circumference of the net at the fore end of a meshed part and b the stretched length of the whole net from wing tip to the end of cod-end. 2. In the condition-varied nets, the vertical opening of head rope showed some increase in every type net except the C type, and the increase showed the greatest in the B type by 30~54%, whereas it showed decrease in the C type by 5~10%. Variation of the area of net mouth showed almost the same tendency as the vertical opening and the increase showed the greatest in the B type by 20%, whereas it showed decrease in the C type by 12%. Hydrodynamic resistance showed some increase in every type compared with the standard net, and the rate of increase indicated 5~10% in the A-2, A-3 and A-4 type, 22% in the B type and 3% in the C type.

• Clean Technology
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• v.17 no.1
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• pp.62-68
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• 2011

Hydrodynamic characteristics in multistage annular type fluidized bed (riser: $0.01{\times}0.025{\times}2.8m^3$, J-valve: $0.009{\times}0.015m^2$)were investigated. Glass beads ($d_p=101{\mu}m$, ${\rho}_b=1,590kg/m^3$, $U_{mf}=1.25{\times}10^{-2}m/s$, Geldart classification B) was used as a bed material. Accumulated weight by the electronic balance was measured to determine the solid flow rate in batch-type. In circulation condition, we measured the accumulated weight of particle transported from riser. At the steady state condition, solid circulation rate was calculated from time interval of the heated bed material passing between two thermocouples. Solid flow rate increased with increasing inlet gas velocity ($1.2-2.6U_{mf}$) and the static bed height (z, 0.24-0.68 m) from 2.2 to 23.4 kg/s. However, mean residence time decreased with increasing inlet gas velocity ($1.2-2.6U_{mf}$) and the static bed height (z, 0.24-0.68 m) from 1,438 to 440 s. The solid holdup in the riser was determined by measuring pressure differences according to the riser height. These results showed a similar trend to that of simple exponential decay type except for the top section of the riser. To verify the gas bypassing from top bubbling beds to middle bubbling beds, $CO_2$ gas was injected by tracer gas in constant ratio, and then was measured $CO_2$ concentration in outlet gas by gas chromatography. Gas bypassing occurred below 2.6% which is negligible value.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.428-434
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• 1995

The purpose of this study is to develop a sanitary aquarium for the safety slices of raw fish by using U.V. light. Water re-circulating system was composed of two tanks. One of the tanks $(90\times45\times45cm\;in\;size),$ was used for rearing fish and the other $(90\times45\times45cm\;in\;size),$ with 37 pieces of corrugated plastic plates was used for the growth of Nitrosomonas and Nitrobacter to remove ammonia from the water. Consequently, bactericidal effects of U.V. light were examined under the controlled condition of water with flow rate 730m1/sec (water flow thickness: 10mm), the width 41cm of water flow route, and the distance 4.75cm from the lamp to its water bottom, and U.V. light 75W (5 lamps). The water of the aquarium tank will be theroetically circulated 1 cycle per 18 min. In these conditions the bactericidal effect was $85\%$ just after passing through U,V. light and 3 log cycle in aquarium tank water. The count of Vibrio parahaemolyticus just after irradiation was decreased by about over than 3 log cycle. Under the irradiation for 72 hours, viable cell counts in both skin and gill of fish reared were decreased into about 2 log cycle, but there was no significant decrease in viscera. When the temperature of the tank was controlled at about $20-23^{\circ}C$ under the same condition, viable cell counts were reduced about 2 log cycle, and fecal coliforms were reduced about 1 log rycle and 3 log cycle in Crassostrea gigas and Mytilus edulis, respectively.

• The Journal of Internal Korean Medicine
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• v.16 no.1
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• pp.40-61
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• 1995

This study was performed to investigate concept, systoms, causes of disease, pathogenic mechanisms, therapies and precriptions about senile constipation through the successive medical literature, recent chinese medical literature and chinese medical joumals. Senile constipation seems to be applicable to dryness syndrom and constipation of insufficiency type, have something to do with kidney(the most), lung, spleen and large intestine. The most principal cause of disease is yin-fluid, the rest deficiency of qi, insufficiency of yang, stagnation of qi and retention of fever etc. There are enriching the blood and moistening dryness in principal therapy, the rest are invigorating qi and loosing the bowel, warming and invigorating the spleen and kidney, regulating the flow of qi and promoting the stagnancy of qi and expelling the pathogenic heat etc. In prescriptions there are Yunjangtang, Jengaektang, Hwanggitang, Jechunjeon, Yukmatang and Majainhwan as the causes of disease, meanwhile are Yungjang-tang, Jechunjeon and Majainhwan in the vulgaris prescriptions. And in medical herbs there are nourishing yin medicines as Rhizoma rehmanniac, Radix ophiopogonis and Radix scrophulariae etc., invigorating qi medicines as Radix astragali, Radix codonopsitis and Radix polygoni multiflori etc, invigorating yang medicines as Caulis cistanchis and Semen psoraleae etc., promoting qi circulating medicines as Radix saussurea, Lignum aquilariae and Radix linderae etc., and reducing fever and therapeutic method to keep the adverse qi flowing downward medicines as Semen cannabis, Rhizoma rhei, Fructus immaturus ponciri, and Cortex magnoliae etc.. Meantime Rhizoma rehmanniae, Radix ophiopogonis, Caulis cistanchis, Radix angelicae gigantis, Semen cannabis, Semen biotae, Semen pruni japonicae and Semen persicae in principal herb-medicines. In clinical reports the process of disease was between 10 to 20 years, the evacuation cycle between 4 to 7 days, generally possessed chronic diseases as hypertension, diabetes, arteriosclerosis and cerebro- vascular disorders etc. and the efficiency rate was more than 90%. The senile constipation is occured in succession or promoted by chronic diseases as obesity, hypertension, diabetes, arteriosclerosis. hrperlipemia, cerebro- vascular disorders etc., so diet-regulating, adequate exercise, proper evacuation-habit and psychologic rest etc. are important more than medicine-treatments.

• Journal of the Korean Solar Energy Society
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• v.38 no.5
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• pp.49-62
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• 2018

This study aims to analyze the performance of solar thermal system with heat pump for domestic hot water and heat supply. There are four types of system. Systems are categorized based on the existence of a heat pump and the ways of controlling the working fluid circulating from the collector. Working fluid is controlled by either temperature level (categorized as system 1 and 2) or sequential flow (system 3 and 4). Heat balance of the system, the solar fraction, hot water and heating supply rates, and performance of heat pump are analyzed using TRNSYS and TESS component programs. Technical specifications of the main facilities are as follow; the area of the collector to $25m^2$, the volumes of the main tank and the buffer tank to $0.5m^3$ and $0.8m^3$, respectively. Heating capacity of the heat pump in the heating mode is set to 30,000 kJ / hr. Hot water supply set 65 liters per person each day, total heat transfer coefficient of the building to 1,500 kJ / kg.K. Indoor temperature is kept steadily around $22^{\circ}C$. The results are as follows; 6 months average solar fraction of system 1 turns out to be 39%, which is 6.7% higher than system 2 without the heat pump, indicating a 25% increase of solar fraction compared to that of system 2. In addition, the solar fraction of system 1 is 2% higher than that of system 3. Hot water and heating supply rate of system 1 are 93% and 35%, respectively. Considering the heat balance of the system, higher heat efficiency, and solar fraction, as whole, it can be concluded that system 1 is the most suitable system for hot water and heat supply.