• Title/Summary/Keyword: pump

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An Investigation of the Pump Operating Characteristics as a Novel Control Index for LVAD Control

  • Choi Seongjin;Boston J. Robert;Antaki James F.
    • International Journal of Control, Automation, and Systems
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    • v.3 no.1
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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.

Comparision of Body Image between DM Patients who used Insulin Pump and didn't use Insulin Pump (인슐린 펌프 착용 유무에 따른 당뇨병환자의 신체상 비교)

  • Lee, Myung-Hwa;Woo, Kyung-Mi;Kim, Kyung-Hee
    • The Korean Journal of Rehabilitation Nursing
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    • v.4 no.2
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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.

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Development of the Driving Pump for the Super-cavitation & High-speed Cavitation Tunnel (초공동 고속 캐비테이션 터널 구동펌프 개발)

  • Ahn, Jong-Woo;Kim, Gun-Do;Paik, Bu-Geun;Kim, Kyoung-Youl
    • Journal of the Society of Naval Architects of Korea
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    • v.55 no.2
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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.

Comparision of Body Image between DM patients who used Insulin Pump and didn't use Insulin Pump (인슐린 펌프 착용 유무에 따른 당뇨병환자의 신체상 비교)

  • Lee, Myung-Hwa;Woo, Kyung-Mi;Kim, Kyung-Hee
    • The Korean Journal of Rehabilitation Nursing
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    • v.4 no.1
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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.

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Pump performance analysis of Axial Flow Blood Pump using CFD (CFD를 활용한 축류형 혈액펌프의 펌프 특성 해석)

  • 최승한;김동욱
    • Proceedings of the KAIS Fall Conference
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    • 2003.06a
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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.

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Characteristics of a Small Screw-type Centrifugal Pump Operating in Air-Water Two-Phase Flow (소형 스크류식 원심펌프의 기액 이상류 특성)

  • Kim, You-Taek;Tanaka, Kazuhiro;Lee, Young-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.2 no.4 s.5
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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.

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Numerical Analysis on the Flow Uniformity in a Pump Sump Model with Multi Pump Intake (다중 흡수정을 갖는 펌프장 모델의 유동균일성 해석)

  • Choi, Jong-Woong;Choi, Young-Do;Lim, Woo-Seop;Lee, Young-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.12 no.4
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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.

The Effect of Pump Intake Leaning Angle and Flow Rate on the Internal Flow of Pump Sump

  • Lee, Youngbum;Kim, Kyung-Yup;Chen, Zhenmu;Choi, Young-Do
    • The KSFM Journal of Fluid Machinery
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    • v.20 no.1
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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.

Design loop-filter for GHz-range charge-pump PLL (GHz급 charge-pump PLL응용을 위한 루프 필터 설계)

  • 정태식;전상오
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.11
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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.

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Development of Simulation Software for Metering Pump of Synthetic Fibers with Image Processing (영상처리 기법에 의한 합섬방사용 미터링 펌프의 시뮬레이션 소프트웨어 개발)

  • Cho Yon-Sang;Bae Myung-Ho
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.3 s.168
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    • pp.101-106
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    • 2005
  • It needs to accumulate a store of know-how on the design, precision processing and appraisement for metering pump which is a kind of gear pump fer synthetic fibers. But the period and cost fur development is not effective, because designers experience many trial and error for the pump design and manufacturing process. Therefore, in order to curtail the period and cut down expenses, the analysis and simulation system is required for a designed metering pump. In this study, the pump simulation software was developed with the visual C++ language and the image processing algorithm, and was investigated through a discharge test for the planetary gear type metering pump.