• Title/Summary/Keyword: flow contraction

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Study on the Anti-inflammatory, Analgesic and Anti-thrombotic Effects of Shintongchugeotang in the Experimental Animals (신통축어탕(身痛逐瘀湯)의 항염(抗炎), 진통(鎭痛) 및 항열전효과(抗血栓效果)에 관(關)한 연구(硏究))

  • Liu, Ji-Yong;Lee, Gi-Sang;Moon, Byung-Soon
    • The Journal of Internal Korean Medicine
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    • v.18 no.1
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    • pp.69-85
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    • 1997
  • This study was designed to elucidate the anti-inflammatory, cardiovascular, anti-thrombotic and analgesic effects of Shintongchugeotang. The anti-inflammatory effect was measured by the method of carragenin induced edema, protein leakage test using CMC-pouch, and the analgesic effect was measured by the acetic acid method and hot plate method, and the effect of Shintongchugeotang on the cardiovascular system was observed by the change of flow rate of Ringer solution in the vascular system in the ear of rabbit, and the contraction and dilatation of rat tail artery. Death rate, platelet aggregation, plasma coagulation activity was observed for the measurement of the anti-coagurative effect of Shintongchugeotang. The result was as follows : 1. After the administration of Shintongchugeotang extract, Carragenin induced edema and CMC-pouch protein leakage were significantly decreased. 2. The slight analgesic effect of Shintongchugeotang extract was confirmed by the observation of writhing syndrome, paw licking time, and escape time. 3. The drug increased the auricular blood flow in rabbit. 4. The drug relaxed the artery contraction by pretreated norepinephrine in rat. 5. The drug inhibited the death rate of mouse which was led to thromboembolism by serotonin and collagen. 6. The drug inhibited the platelet aggregation in rat. 7. The drug prolonged the prothrombin time and activated partial thromboplastin time on the test of plasma coagulation factor activity in rat, but was not valuable.

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Study on the Antiinflammatory, Anticoagulative and Analgesic effects of Sambitang in the experimental animal model (삼비탕(三痺湯)의 항염(抗炎), 항응고(抗凝固) 및 진통효과(鎭痛效果)에 대(對)한 연구(硏究))

  • Rhy, Jun-Kiu;Lee, Young-Goo;Moon, Byung-Soon
    • The Journal of Internal Korean Medicine
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    • v.19 no.2
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    • pp.88-106
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    • 1998
  • This study was designed to elucidate the antiinflammatory, cardiovascular, antithrombotic, and analgesic effect of Sambitang. The antiinflammatory effects was measured by the method of carrageenin induced edema, protein leakage test using CMC-pouch, and the effect of Sambitang on the cardiovascular system was observed by the change of flow rate of Ringer solution in the vascular system in the ear of rabbit, and the contraction and dilatation of rat tail artery. Death rate, platelet aggregation, plasma coagulation activity was observed for the measurement of the anticoagurative effect of Sambitang, and the analgesic effect was measured by the acetic acid method and hot plate method. The result was as follows: 1. Sambitang administration, edema and protein leakage was significantly decreased. 2. The drug increased the auricular blood flow in rabbit. 3. The drug relaxed the artery contraction by pretreated norepinephrine in rat. 4. The drug inhibited the death rate of mouse which was led to thromboembo- lism by serotonin and collagen. 5. The drug inhibited the platelet aggregation in rat. 6. The drug prolonged the prothrombin time and activated partial thromboplastin time on the test of plasma coagulation factor activity in rat, but was not valuable. 7. The slight anagesic effect of Sambitang extract was confirmed by the observation of writhing syndrome, paw licking time, and escape time.

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Effects of GwakHyangJungGiSan on the Arterial Contraction in Rabbit (곽향정기산(藿香正氣散)이 가토(家兎)의 수축혈관에 마치는 영향(影響))

  • Sun Jung-Ki;Kim Ho-Hyun;Nam Chang-Gyu;Koo Chang-Mo
    • The Journal of Internal Korean Medicine
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    • v.24 no.2
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    • pp.260-268
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    • 2003
  • Object : This study was undertaken to define the mechanism of GwakHyangJungGiSan-induced relaxation in rabbit common carotid artery contracted by agonists. Method : In order to investigate the effect of GwakHyangJungGiSan on rabbit's contracted vascular ring detached from common carotid artery, vascular ring intact or damaged endothelium was used for the experiment using organ bath. To analyze the mechanism of GwakHyangJungGiSan-induced relaxation, GwakHyangJungGiSan extract was infused into contracted vascular ring which had been pretreated by pretreatment of indomethacin(IM), tetraethylammonium chloride(TEA), $N{\omega}-nitro-L-arginine(L-NNA)$. Result : GwakHyangJungGiSan blocks an inflow of $Ca^{2+}$ and relaxes vascular ring by the action of Nitric oxide from endothelium. Consequently when GwakHyangJungGiSan is prescribed, a rise in blood pressure by the resistance of peripheral vessel may be controlled to some extent and so it is anticipated that hypertension, a disorder of blood flow from the vascular contraction and vascular disease will be treated well.

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Clinical and pharmacological application of multiscale multiphysics heart simulator, UT-Heart

  • Okada, Jun-ichi;Washio, Takumi;Sugiura, Seiryo;Hisada, Toshiaki
    • The Korean Journal of Physiology and Pharmacology
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    • v.23 no.5
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    • pp.295-303
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    • 2019
  • A heart simulator, UT-Heart, is a finite element model of the human heart that can reproduce all the fundamental activities of the working heart, including propagation of excitation, contraction, and relaxation and generation of blood pressure and blood flow, based on the molecular aspects of the cardiac electrophysiology and excitation-contraction coupling. In this paper, we present a brief review of the practical use of UT-Heart. As an example, we focus on its application for predicting the effect of cardiac resynchronization therapy (CRT) and evaluating the proarrhythmic risk of drugs. Patient-specific, multiscale heart simulation successfully predicted the response to CRT by reproducing the complex pathophysiology of the heart. A proarrhythmic risk assessment system combining in vitro channel assays and in silico simulation of cardiac electrophysiology using UT-Heart successfully predicted drug-induced arrhythmogenic risk. The assessment system was found to be reliable and efficient. We also developed a comprehensive hazard map on the various combinations of ion channel inhibitors. This in silico electrocardiogram database (now freely available at http://ut-heart.com/) can facilitate proarrhythmic risk assessment without the need to perform computationally expensive heart simulation. Based on these results, we conclude that the heart simulator, UT-Heart, could be a useful tool in clinical medicine and drug discovery.

Application of Superfluid Shock Tube Facility to experiment of High Reynolds number flow (초유동 충격파관 장치의 고레이놀즈수 유동실험에의 응용)

  • ;H. Nagai;Y. Ueta;K. Yanaka;M. Murakami
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.27-30
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    • 2002
  • The particle velocity in superfluid helium (He II) induced by a gas dynamic shock wave impingement onto He II free surface were studied experimentally by using Schlieren visualization method with an ultra-high speed video camera. It is found form visualization results that a dark zone in the immediate vicinity of the vapor-He II interface region is formed because of the high compressibility of He II and is developed toward bulk He II with the flowing-down speed of the vapor-He II interface. The mass velocity behind a transmitted compression shock wave that is equal to the contraction speed of He II amounts to 10 m/sec, the Reynolds number of which reaches $10^{7}$. This fact suggests that the superfluid shock tube facility can be applied to an experimental facility for high Reynols number flow as an alternative to the superfluid wind tunnel.

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CONTRACTION OF HOROSPHERE-CONVEX HYPERSURFACES BY POWERS OF THE MEAN CURVATURE IN THE HYPERBOLIC SPACE

  • Guo, Shunzi;Li, Guanghan;Wu, Chuanxi
    • Journal of the Korean Mathematical Society
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    • v.50 no.6
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    • pp.1311-1332
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    • 2013
  • This paper concerns the evolution of a closed hypersurface of the hyperbolic space, convex by horospheres, in direction of its inner unit normal vector, where the speed equals a positive power ${\beta}$ of the positive mean curvature. It is shown that the flow exists on a finite maximal interval, convexity by horospheres is preserved and the hypersurfaces shrink down to a single point as the final time is approached.

Conceptual design of cryomodules for RAON

  • Kim, Y.;Lee, M.K.;Kim, W.K.;Jang, H.M.;Choi, C.J.;Jo, Y.W.;Kim, H.J.;Jeon, D.
    • Progress in Superconductivity and Cryogenics
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    • v.16 no.3
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    • pp.15-20
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    • 2014
  • The heavy ion accelerator that will be built in Daejeon, Korea utilizes superconducting cavities operating in 2 K. The cavities are QWR (quarter wave resonator), HWR (half wave resonator), SSR1 (sing spoke resonator1) and SSR2. The main role of the cryomodule is supplying thermal insulation for cryogenic operation of the cavities and maintaining cavities' alignment. Thermal and structural consideration such as thermal load by heat leak and heat generation, cryogenic fluid management, thermal contraction, and so on. This paper describes detailed design considerations and current results have being done including thermal load estimation, cryogenic flow piping, pressure relief system, and so on.

Characteristics of Performance for Centrifugal Blower with Different Outlet Geometries (토출구의 형상에 따른 원심 송풍기의 성능특성)

  • Kim, Jae-Won;Kim, Jin-Min;Lee, Kook-Do
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.70-77
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    • 2004
  • Comprehensive investigation on the outlet's geometric shapes of a centrifugal blower with higher inlet resistance than an atmospheric pressure is carried out for improvements of its performance. Most unwanted behaviors of such blower are pulsating flows because of unbalance between inflows and outflows in a scroll casing. In order to reduce this undesirable phenomenon a triump is made for both the shape of outlet duct and an accessory structure inserted in the outlet port of the blower. The modification on the shape is concerned with the contraction of cross sectional area and the attached structure is for an intentional obstruction to cause a flow resistance. The details of the modification are examined for different cases and results. The methodologies for the work are performance evaluations including noise level and velocity measurements with PIV Consequently, the performance of improved system is close to that of the system operating with atmospheric pressure at the inlet.

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Optimization of supersonic ejector (2차 노즐목을 갖는 초음속 이젝터의 최적화)

  • Park, Hyung-Ju;Yoon, Shi-Kyung;Yeom, Hyo-Won;Sung, Hon-Gye
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.130-134
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    • 2010
  • The effects of design parameters of supersonic ejector system under the assumption of constant pressure mixing were performed. Design parameters were mass flow rate ratio, area ratio between primary and secondary flow, and primary Mach number. 1-D theoretical performance of ejector in terms of pressure ratio and contraction ratio with and without loss mechanism such as diffuser efficiency and friction were considered.

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Analysis on Wave Absorbing Performance of a Pile Breakwater (파일 방파제의 소파성능 해석)

  • Cho, Il-Hyoung;Koh, Hyeok-Jun
    • Journal of Ocean Engineering and Technology
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    • v.21 no.4
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    • pp.1-7
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    • 2007
  • Based on the eigenfunction expansion method, the wave-absorbing performance of a square or circular pile breakwater was investigated. Flow separation resulting from sudden contraction and expansion is generated and is the main cause of significant energy loss. Therefore, evaluation of an exact energy loss coefficient is critical to enhancing the reliability of the mathematical model. To obtain the energy loss coefficient, 2-dimensional turbulent flow is analyzed using the FLUENT commercial code, and the energy loss coefficient can be obtained from the pressure difference between upstream and downstream. It was found that energy loss coefficient of circular pile is 20% that of a square pile. To validate the fitting equation for the energy loss coefficient, comparison between the analytical results and the experimental results (Kakuno and Liu, 1993) was made for square and circular piles with good agreement. The array of square piles also provides better wave-absorbing efficiency than the circular piles, and the optimal porosity value is near P=0.1.