• Title/Summary/Keyword: paddle

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In vitro/In vivo Correlation of Sustained Release Diltiazem (딜티아젬서방정을 이용한 In vitro/In vivo 상관성)

  • Choi, Myoeng-Sin;Kang, Chan-Soon;Choi, Bo-Kyung;Hong, Chong-Hui;Kim, Kil-Soo
    • Journal of Pharmaceutical Investigation
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    • v.32 no.4
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    • pp.321-325
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    • 2002
  • IVIVC (In vitro/in vivo correlation) is useful for predicting in vivo results from in vitro data. The aim of this study was to develop IVIVC of sustained release diltiazem. For this purpose, three types of diltiazem tablets with different in vitro dissolution rates were prepared. An in vitro dissolution testing method comprising of paddle apparatus, 50 rpm, water as dissolution medium was developed. Under these condition, we demonstrated that AUCinf could be predicted by evaluating $d_{70%}$ (time dissolved 70%) in vitro since the in vivo AUCinf was correlated with the in vitro $d_{70%}$ (r=-0.9981).

A Study on the flow Characteristics of a Horizontal Paddle Flocculator Installed in a Filtration Plant by PIV (정수장에서의 수평축 응집기 PIV 유동해석)

  • Park, Young-Geun;Lee, Joong-Ryul;Kim, Beom-Seok;Lee, Young-Ho
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.11a
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    • pp.176-177
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    • 2005
  • KOWACO - ChangWon Branch - have conducted the new study which aimed to improve flocculation performance in Mixers. The Purposes in this study were increasing flocculation efficiency by finding significant factor which was affected flow characteristics. In the result of this research we modified the error in equation of G-value and RPM which have been used till quite recently. Also we developed program auto-calculating G-value and RPM and then we had made their statistical list. We had conducted experiment with flocculation Mixer's model sized 1/10 by PIV's method. We analysed characteristic of all flow fields by changing case such as changing direction of flocculator roatation etc.

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Analyses Thermal Stresses for Microaccelerometer Sensors using SOI Wafer(I) (SOI웨이퍼를 이용한 마이크로가속도계 센서의 열응력해석(I))

  • Kim, O.S.
    • Journal of Power System Engineering
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    • v.5 no.2
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    • pp.36-42
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    • 2001
  • This paper deals with finite element analyses of residual stresses causing popping up which are induced in micromachining processes of a microaccelerometer sensors. The paddle of the micro accelerometer sensor is designed symmetric with respect to the direction of the beam. After heating the tunnel gap up to 100 degree and get it through the cooling process and the additional beam up to 80 degree and get it through the cooling process. We learn the thermal internal stresses of each shape and compare the results with each other, after heating the tunnel gap up to 400 degree during the Pt deposition process. Finally we find the optimal shape which is able to minimize the internal stresses of microaccelerometer sensor. We want to seek after the real cause of this pop up phenomenon and diminish this by change manufacturing processes of microaccelerometer sensor by electrostatic force.

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Revision of Lateral Arm Free Flap; Can It be a Substituete for Radial Forearm Free Flap? (외측상박 유리피판의 유용성에 관한 재조명; 전박부 유리피판을 대체할 수 있는가?)

  • Ahn, Hee-Chang
    • Archives of Reconstructive Microsurgery
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    • v.6 no.1
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    • pp.80-86
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    • 1997
  • The lateral arm flap was reported first by Song et al. in 1982, and Katsaros and colleagues described an anatomic study and clinical cases in 1984. This flap is thin, has relatively constant vascular anatomy, and provides relatively acceptable scar at the donor site. Despite its many advantages its wide application has been limited by its short vascular pedicle with small diameter of lumen, and its small skin paddle. We studied its anatomical structure to get longer length of vascular pedicle, wide diameter and thinner part of flap beyond the lateral condyle through 6 fresh cadaver dissection and dye injection study. We experienced 21 cases of lateral arm free flaps and 26 cases of forearm free flaps from May, 1992 to January, 1996. We compared its usefulness with forearm free flaps in the aspects of donor morbidity, operative factors, quality of flap, and versatility. In conclusion, lateral arm flap can replace the role of forearm flap in most cases so that patient's donor morbidity can be reduced especially in the women.

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Numerical investigation of floating breakwater movement using SPH method

  • Najafi-Jilani, A.;Rezaie-Mazyak, A.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.3 no.2
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    • pp.122-125
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    • 2011
  • In this work, the movement pattern of a floating breakwater is numerically analyzed using Smoothed Particle Hydrodynamic (SPH) method as a Lagrangian scheme. At the seaside, the regular incident waves with varying height and period were considered as the dynamic free surface boundary conditions. The smooth and impermeable beach slope was defined as the bottom boundary condition. The effects of various boundary conditions such as incident wave characteristics, beach slope, and water depth on the movement of the floating body were studied. The numerical results are in good agreement with the available experimental data in the literature The results of the movement of the floating body were used to determine the transmitted wave height at the corresponding boundary conditions.

Air Flow Sensor with Corrugation Structure for Low Air Velocity Detection (주름구조를 적용한 저속 유속 센서)

  • Choi, Dae-Keun;Lee, Sang-Hoon
    • Journal of Sensor Science and Technology
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    • v.20 no.6
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    • pp.393-399
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    • 2011
  • In this paper, we designed and fabricated the novel air flow sensor using air drag force, which can be applied to the low air flow detection. To measure the low air flow, we should enlarge the air drag force and the output signal at the given air flow. The paddle structure is applied to the device, and the device is vertically located against the air flow to magnify the air drag force. We also adapt the corrugation structure to improve the output signals on the given air velocity. The device structure is made up of the silicon nitride layer and the output signal is measured with the piezoresistive layer. The output signals from the corrugated device show the better measurement sensitivity and the response time than that of flat one. The repeated measurement also shows the stabilized signals.

Theoretical Approach to Calculating rms-Velocity Gradient in Flocculators (응집지 속도경사(G) 계산에 대한 이론적인 고찰)

  • Kim, Ja-Kyum
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.3
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    • pp.351-356
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    • 2004
  • Selecting appropriate G values in flocculator operation is important to produce high quality filter effluent in water treatment plants. However, misunderstanding and misleading of G calculation for the case of having power sources more than one or many paddles with one power source in a flocculation basin sometimes have led to low performance in flocculation. Theoretical analysis confirmed that the total G value in one flocculation unit having power sources more than one or with many paddles is the root-square of the sum of square of individual G value. This analysis also can give a simple calculation method of G value for designers and operators in fields.

Transient Simulation of Solid/Liquid Two-Phase Flow in a Stirred Tank (교반기 내부의 고체/액체 다상 유동의 비정상상태 해석)

  • Kim, Chi-Gyeom;Yong, Suk-Jin;Won, Chan-Shik;Hur, Nahm-Keon
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.236-239
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    • 2008
  • In the present study, a transient glass particle distribution in a stirred solid/liquid mixer was investigated using computational fluid dynamics(CFD). The flow patterns and solid concentaration distriburion in a solid/liquid mixer formed by pitched paddle and baffles were predicted. The numerical results were compared to experimental data from the available literature. Eulerian multi-phase model was used to investigate the influence of the density of solid particle on the same impeller speed. A good agreement was obtained between the experimental data and simulation results.

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The effect of electrolysis conditions on the composition and preferred orientation of Ni-Fe alloy electrodeposits (Ni-Fe합금도금층의 조선 및 우선배향에 미치는 전해조건의 영향)

  • 예길촌;김용웅;김용희;김용주
    • Journal of the Korean institute of surface engineering
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    • v.27 no.6
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    • pp.319-326
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    • 1994
  • The effects of electrolysis conditions on the composition and preferred orientation of Ni-Fe alloy were studied using the sulfate-chloride baths paddle agitated. Cathode current efficiency is higher in the deposits from bath 2 than that of deposits from bath 1. The Fe content of alloy deposits from bath 2 is nearly constant(19∼21wt.%) in the wide range of current density, while it decreases noticeably with current density in the deposits from bath 1. The variation of Fe content at the edge of specimen is lower in deposits from bath 2 than those from bath 1. The alloy deposits show (111) & (200) preferred orientation for the deposits from bath 1 and bath 2 respectively.

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Composition, preferred orientation and magnetic properties of Ni-Fe-Co alloy electrodeposits (Ni-Fe-Co 박막도금층의 조성, 우선배향 및 자기적 성질)

  • 예길촌;김선윤;문근호;김용웅
    • Journal of the Korean institute of surface engineering
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    • v.28 no.6
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    • pp.352-360
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    • 1995
  • The effect of electrolysis conditions on the composition, the magnetic properties and the preferred orientation of Ni-Fe-Co alloy deposits was investigated using the sulfate-chloride bath paddle agitated. Cathode current efficiency increases with the current density, showing the different tendency of the variation from that of the Ni-Fe electrodeposits. The Co content of the deposits decreases with increasing current density, while the content of Ni and Fe is shown to be minimum or maximum at 3A/$dm^2$ respectively. The Ni/Fe ratio of the alloy deposits is lower than that of Ni-Fe deposits. The coercive force($H_c$) of the deposits increases with the Co content in deposit, showing the relatively low value in the range of 1.8~5.0Wt.% Co. The anisotropy field ($H_k$) of the deposits is higher than that of Ni-Fe alloy deposits, The preferred orientation of the deposits is generally (200), but the orientation factor(R) changes with both the increase of current density and the magnetic field applied during deposition.

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