• International Journal of Control, Automation, and Systems
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• 제3권1호
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• pp.100-108
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• 2005

This work presents a novel control index to regulate the pump speed of an axial flow blood pump for the left ventricular assist device (LVAD). The control index is based on the characterization of pump operating conditions such as normal or suction status. The pump operating characteristics reveal that a certain pulsatility relationship between the pump pressure difference and the pump flow is a unique index to identify the pump operating status under the diverse pump operating environments.

• 재활간호학회지
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• 제4권2호
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• pp.251-264
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• 2001

The purpose of study was to compare body image between diabetes mellitus patients who used insulin pump therapy and didn't use insulin pump therapy. The study design was comparative survey study the subjects were 60 diabetes mellitus patients who used insulin pump therapy and 60 diabetes mellitus patients who didn't use insulin pump therapy at B hospital in Busan. The data were collected from 15th April to 20th August, 1998. The instrument used for this study were Osgood's body image scale. The collected data were analyzed frequency, percentage, $X^2$-test, mean, standard deviation, t-test, ANOVA, Scheffe test. The results were as follows 1. Demographical characteristics between diabetes mellitus patients who used insulin pump therapy and didn't use insulin pump therapy were no significant difference. 2. Characteristics related disease between diabetes mellitus patients who used insulin pump therapy and didn't use insulin pump therapy were significant difference in paticipation of D.M. meeting, no of paticipation of D.M. meeting. 3. Body inmage score of diabetes mellitus patients was $69.08{\pm}18.13$. In body image, diabetes mellitus patients who used insulin pump therapy were higher than that didn't use insulin pump therapy(t=1.964, P<.05) 4. In body image's each item, common-strange item, noble-humble item, competent-incompetent item, light-heavy item, diabetes mellitus patients who used insulin pump therapy were higher than diabetes mellitus patients who didn't use insulin pump therapy(P<.05). 5. In body image according to economic status, marital status, occupational status were significantly difference. 6. In body image according to causes of regular hospital visiting, paticipation of diabetes mellitus class were significantly difference. In conclusion, diabetes mellitus patients who used insulin pump therapy were more positive than diabetes mellitus patients who didn't use insulin pump therapy.

• 대한조선학회논문집
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• 제55권2호
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• pp.153-160
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• 2018

In order to develop the driving pump for High-speed Cavitation Tunnel(HCT) which can experiment the super-cavitating submerged body, KRISO decided on the pump specification, designed the mixed-flow pump on the basis of the existing pump data and predicted the performance of the design pump using commercial CFD code (CFX-10). After the manufacture and installation of the driving pump, KRISO conducted the trial-test for HCT, analyzed the pump performance and compared trial-test results to those of design stage. The trial-test items for the HCT driving pump are measurements of output current/voltage at the inverter of the driving pump and the flow velocity in the HCT test section. The trial-test results showed the decrease in the flow rate of about 4.6% and the increase in pump head of about 8%, compared with those of the pump prediction. After the trial-test, the performance of the driving pump is predicted using CFX-10 with measured flowrates and pump rotational velocities. Though there is some difference between trial-test and prediction results due to inadequate motor data, it is thought that the tendency is reasonable. It is found that CFX-10 is useful to predict a mixed-flow pump.

• 재활간호학회지
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• 제4권1호
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• pp.105-118
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• 2001

The purpose of study was to compare body image between diabetes mellitus patients who used insulin pump therapy and didn't use insulin pump therapy. The study design was comparative survey study the subjects were 60 diabetes mellitus patients who used insulin pump therapy and 60 diabetes mellitus patients who didn't use insulin pump therapy at B hospital in Busan The data were collected from 15th April to 20th August, 1998. The instrument used for this study were Osgood's body image scale. The collected data were analyzed frequency, percentage, $X^2$-test, mean, standard deviation, t-test, ANOVA, Scheffe test. The results were as follows 1. Demographical characteristics between diabetes mellitus patients who used insulin pump therapy and didn't use insulin pump therapy were no significant difference. 2. Characteristics related disease between diabetes mellitus patients who used insulin pump therapy and didn't use insulin pump therapy were significant difference in paticipation of D.M. meeting, no of paticipation of D.M. meeting. 3. Body inmage score of diabetes mellitus patients was $69.08{\pm}18.13$. In body image, diabetes mellitus patients who used insulin pump therapy were higher than that didn't use insulin pump therapy(t=1.964, P<.05) 4. In body image's each item, common-strange item, noble-humble item, competent-incompetent item, light-heavy item, diabetes mellitus patients who used insulin pump therapy were higher than diabetes mellitus patients who didn't use insulin pump therapy(P<.05) 5. In body image according to economic status, marital status, occupational status were significantly difference. 6. In body image according to causes of regular hospital visiting, paticipation of diabetes mellitus class were significantly difference. In conclusion, diabetes mellitus patients who used insulin pump therapy were more positive than diabetes mellitus patients who didn't use insulin pump therapy.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2003년도 춘계학술발표논문집
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• pp.288-290
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• 2003

Artificial heart is divided by pulsation flow type and continuous flow type according to blood circulation pattern. Axial flow blood pump is a kind of continuous flow type artificial heart. Axial flow blood pump would be different pump performance according to impeller's shape and rotating velocity. Pump performance be able to compare by flow rate according to differential pressure and Impeller's rotating velocity. It confirms Impeller model of better efficiency according to compare Pump performance of axial flow blood pump using CFD with actual experiment result.

• 한국유체기계학회 논문집
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• 제2권4호
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• pp.9-15
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• 1999

A screw-type centrifugal pump was manufactured to carry primarily solids and its impeller had a wide flow passage. However, there was an effect on the flow passage shape on delay of the choke due to entrained air not being clarified yet. Moreover, because its impeller has a particular shape, only few studies have tried to clarify the pump performance and details of internal flow pattern of that pump. For this reason, we carried out the pump performance experiment under air-water two-phase flow condition with different impeller tip clearances, pump rotational speeds and void fractions by using a small screw-type centrifugal pump designed to acquire basic data. In a general centrifugal pump, it was reported that there was a loss of pump head from single-phase flow to the choke due to air entrainment near the best efficiency point being large. However, the loss near the best efficient point in a screw-type centrifugal pump became less than that in a general centrifugal pump.

• 한국유체기계학회 논문집
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• 제12권4호
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• pp.14-22
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• 2009

The head-capacity curves for pumps developed by the pump manufacturer are based on tests of a single pump operating in a semi-infinite basin with no close walls or floors and with no stray currents. Therefore, flow into the pump intake is with no vortices or swirling. However, pump station designers relying on these curves to define the operating conditions for the pump selected sometimes meet the reductions of capacity and efficiency, as well as the increase of vibration and additional noise, which were caused by air-entered flow in the pump station. From this background, the authors are carrying out a systematic study on the flow characteristics of intakes within a sump of pump station model. Multi-intake sump model with anti-submerged vortex device basin is designed and the characteristics of submerged vortex is investigated in the flow field by numerical simulation. In this study, a commercial CFD code is used to predict the vortex generation in the pump station accurately. The analysed results by CFD show that the vortex structure and effect of anti-submerged vortex device are different at each pump intake channel.

• Nuclear Engineering and Technology
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• 제56권7호
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• pp.2576-2583
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• 2024

In this paper, the similarity criterion and dimensionless conversion method combined with the elasticity condition and Hooke's law are used to derive the functional relationship of the maximum effective value of the vibration velocity between the prototype pump and the model pump. The seawater circulation pump of a nuclear power plant is used as the prototype pump, and the model pump is obtained by performance conversion and choosing the appropriate scale, and the vibration state of the model pump under different flow rates is measured and analyzed. The vibration data of the model pump through the function relationship to find out the vibration parameters of the prototype model pump, and compare with the vibration data of the seawater circulation pump in reality. It can be seen that with the increase of flow rate, the maximum effective value of the vibration velocity of both model and prototype decreases and then increases, and the relative error is small, the maximum value is 7.7757%. Therefore, it can be considered that the functional relationship of model pump converted to prototype pump derived in this paper can be used to analyze the vibration of the actual seawater circulation pump of coastal nuclear power plant.

• 한국유체기계학회 논문집
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• 제20권1호
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• pp.74-80
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• 2017

Pump sump system or pumping stations are built to draw water from a source such as river and used for irrigation, thermal power plants etc. If pump sump is improperly shaped or sized, air entraining vortices or submerged vortices may develop. This may greatly affect pump operation if vortices grow to an appreciable extent. Moreover, the noise and vibration of the pump can be increased by the remaining of vortices in the pump flow passage. Therefore, the vortices in the pump flow passage have to be reduced for a good performance of pump sump station. In this study, the effect of pump intake leaning angle and flow rate on the pump sump internal flow has been investigated. There are three cases with different leaning angle. Moreover, a pipe type with elbow also has been studied. The flow rate with three classes of air entraining vortices has been examined and investigated by decreasing the water level. The result shows that the air entraining vortices easily occurs at the pump intake with large leaning angle. Moreover, the elbow type of the pump intake easily occurs air entraining vortices at the high flow rate (or velocity) in comparison to other pump intake type.

• 전자공학회논문지C
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• 제34C권11호
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• pp.76-85
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• 1997

Charge-pump loop filter was designed using GaAs MESFET for GHz-range PLL system applications. Characteristics of charge-pump loop filter and stability of charge-pump PLL, system were analyzed. Performance specifications were defined and a charge-pump loop filter was designed that satisfies these specifications.