• Journal of Veterinary Clinics
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• v.30 no.1
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• pp.27-31
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• 2013

We investigated the effects of Ponciri Fructus (PF) and Aurantii Fructus Immaturus (AI) on the cicular and longitudinal smooth muscle of rat gastric fundus. Methanol extracts of PF (PFM) and AI (AIM), water-fractions (PFW, AIW) and chloroform-fractions (PFC, AIC) of the extracts induced relaxation in the rat fundic circular muscle pre-contracted by U46619. All extracts showed relaxation without significant differences among the extracts. In the longitudinal smooth muscle, PFM and its water fraction, PFW, showed multiphasic effects, fast relaxation and rebound contraction followed by lasting relaxation. AIM and AIW showed diphasic effects, transient contraction followed by lasting relaxation. However, PFC and AIC induced only relaxation in the rat fundic longitudinal muscle contracted by U46619. PFM showed significantly more effective relaxation compared with PFW, AIM and AIW. Hesperidin, flavonoids known as common constituent of PF and AI and it's an aglycon, hesperetin, induced relaxation in both fundic circular and longitudinal smooth muscle pre-contracted by U46619. Poncirin, known as flavonoid content of PF showed also induced relaxation in the both circular and longitudinal smooth muscle pre-contracted by U46619. These results suggest that both PF and AI has relaxing effects on the gastric fundus smooth muscle and its effects might be caused by their flavonoids constituents.

• The Korean Journal of Applied Statistics
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• v.24 no.1
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• pp.45-59
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• 2011

When using X-12-ARIMA for seasonal adjustment, we usually check whether the series has stable seasonality or not via D8 F-tests, Kruskal-Wallis test, and the spectral diagnostics. In this paper, we develop several smooth tests for seasonality based on a Fourier series to improve the spectral diagnostics of X-12-ARIMA. A simulation study is conducted to compare five smooth tests for seasonality and X-12-ARIMA's D8 F-test an Kruskal-Wallis test. The simulation study shows that smooth tests for seasonality performed well compared with D8 F-tests and a Kruskal-Wallis test.

• Structural Engineering and Mechanics
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• v.66 no.4
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• pp.531-542
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• 2018

In this paper an analytical model in a closed form able to reproduce the monotonic flexural response of external RC beam-column joints with smooth rebars is presented. The column is subjected to a constant vertical load and the beam to a monotonically increasing lateral force applied at the tip. The model is based on the flexural behavior of the beam and the column determined adopting a concentrated plasticity hinge model including slippage of the main reinforcing bars of the beam. A simplified bilinear moment-axial force domain is assumed to derive the ultimate moment associated with the design axial force. For the joint, a simple truss model is adopted to predict shear strength and panel distortion. Experimental data recently given in the literature referring to the load-deflection response of external RC joints with smooth rebars are utilized to validate the model, showing good agreement. Finally, the proposed model can be considered a useful instrument for preliminary static verification of existing external RC beam-column joints with smooth rebars for both strength and ductility verification.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.11B
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• pp.999-1006
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• 2003

In the paper, we investigate the impact of handoff on the packet delivery in the Mobile IPv6 networks, where the smooth handoff is adopted. That is measured by an 'unstable time period (UTP)', a 'silence time period(STP)', and a 'handoff time period (HTP)' in the mobile node's perspective. Then, we propose a queuing model to get the exact value of the handoff transient time. The numerical results show that the queuing delay for the handoff packets and the involved link (or route) capacities affect the estimated UTP, STP, and HTP. On the other hand, the damage of application caused by handoff will increases when the handoff transient time becomes longer. We show that the priority scheduling method can achieve shorter STP and UP than the FIFO scheduling method that is generally used in best-effort IP network.

• BMB Reports
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• v.46 no.11
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• pp.550-554
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• 2013

The platelet-derived growth factor (PDGF) signaling pathway is essential for inducing a dedifferentiated state of vascular smooth muscle cells (VSMCs). Activation of PDGF inhibits smooth muscle cell (SMC)-specific gene expression and increases the rate of proliferation and migration, leading to dedifferentiation of VSMCs. Recently, microRNAs have been shown to play a critical role in the modulation of the VSMC phenotype in response to extracellular signals. However, little is known about microRNAs regulated by PDGF in VSMCs. Herein, we identify microRNA- 15b (miR-15b) as a mediator of VSMC phenotype regulation upon PDGF signaling. We demonstrate that miR-15b is induced by PDGF in pulmonary artery smooth muscle cells and is critical for PDGF-mediated repression of SMC-specific genes. In addition, we show that miR-15b promotes cell proliferation. These results indicate that PDGF signaling regulates SMC-specific gene expression and cell proliferation by modulating the expression of miR-15b to induce a dedifferentiated state in the VSMCs.

• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.131-136
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• 2008

Three-dimensional characteristics of fluid flow and heat transfer around a wavy circular cylinder having sinusoidal variation in cross sectional area along the spanwise direction are numerically investigated using the immersed boundary method. The three different wavelengths of ${\pi}/4$, ${\pi}/3$ and ${\pi}/2$ and at the fixed wavy amplitude of 0.1 have been considered to investigate the effects of waviness on especially the forced convection heat transfer around a wavy cylinder when the Reynolds and Prandtl numbers are 300 and 0.71, respectively. The present computational results for a wavy cylinder are compared with those for a smooth cylinder. The time- and total surface-averaged Nusselt number for a wavy cylinder with is larger than that for a smooth cylinder, whereas that with ${\lambda}={\pi}/4$ and ${\pi}/3$ is smaller than that for a smooth cylinder. However, because the surface area exposed to heat transfer for a wavy cylinder is larger than that for a smooth cylinder, the total heat transfer rate for a wavy cylinder with different wavelengths of ${\lambda}={\pi}/4$, ${\pi}/3$ and ${\pi}/2$ is larger than that for a smooth cylinder.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.5
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• pp.1725-1734
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• 1996

Experimental condensation and evaporation heat transfer coefficients were measured in a horizontal smooth tube and a horizontal micro-finned tube with HFC-134a. The test sections are straight, horizontal tubes with have a 9.52mm outside diameter and about 5000mm long. The micro-finned tube had 60 fins with a height of 0.12mm and a spiral angle of 25.deg.. The condensation test section was a double-pipe type with counter flow configuration. The evaporation test section employed an electic heating method. Enhancement factors which is defined as a ratio of the heat transfer coefficient for micro-finned tube to that for smooth tube, varied from 1.3 to 1.6(mass flux:110~190kg/m$^{2}$s) for condensation and 1.2 to 1.5 (mass flux:70~160kg/m$^{2}$s) for evaporation. The experimental data of condensation and evaporation heat transfer coefficients were compared to several empirical correlations. Based on these comparisons, modified correlations of the condensation and evaporation heat transfer coefficient for both smooth and micro-finned tubes were proposed.

• The Journal of Internal Korean Medicine
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• v.13 no.1
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• pp.143-155
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• 1992

The following results were obtained from the observation on the change of plasma cortisol concentration in the experiment of intravenous administration of Haengsoyeum Water Extract in the rabbit. And the effects of Haengsoyeum extract on the contractile force of the isolated guinea pig trachea smooth muscle. 1. In intravenous administration the plasma cortisol concentration increased significantly about 1 hours after with a does of 0.2 ml/kg. 2. In intravenous administration the plasma cortisol concentration increased significantly about from 1 to 3 hours after with a does of 0.4 ml/kg. 3. The contractile response of the trachea smooth muscle of isolated guinea pig to histamine $10^{-4}\;M$ was significantly inhibited by Haengsoyeum extract. 4. The contractile response of the trachea smooth muscle of isolated guinea pig to acetylcholine $10^{-4}\;M$ was considerably inhibited by Haengsoyeum extract. 5. The contractile response of the trachea smooth muscle of isolated guinea pig to 5-hydroxytryptamine $10^{-4}\;M$ was inhibited by Haengsoyeum extract.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.191-198
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• 2014

This paper proposes a simple linear function approximation method to solve an economic load dispatch problem with complex non-smooth generating cost function. This algorithm approximates a non-smooth power cost function to a linear approximate function and subsequently shuts down a generator with the highest operating cost and reduces the power of generator with more generating cost in order to balance the generating power and demands. When applied to the most prevalent benchmark economic load dispatch cases, the proposed algorithm is found to dramatically reduce the power cost than does heuristic algorithm. Moreover, it has successfully obtained results similar to those obtained through a quadratic approximate function method.

• Journal of Food Hygiene and Safety
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• v.11 no.2
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• pp.83-87
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• 1996

The objective of this study is to investigate the direct effects of green tea catechins(GTC) on vascular smooth muscle tension and 45Ca2+ Uptake in rat aorta. The methods used in this study are isometric tension measurements using physiograph, Lanthanum method for 45Ca2+(2 uCi/ml) uptake measurement in rat aorta. GTC modified tension induced by 40 mM KCl or 1 uM norepinephrine in rat aorta. Low concentrations of GTC(<0.5mg/ml) increased tension by 40 mM KCl or 1 uM norepinephrine, individually. However, high conecentration of GTC(>0.5 mg/ml) inhibiited tension by 40 mM KCl or 1 uM norepinephrine, individually. GTC increased 45Ca uptake induced by 40 mM KCl in a dose-dependent manner. From these results, GTC has the dual actions in vascular smooth muscle in vitro. Low concentrations of GTC augments tension by K or norepinephrine. However, high concentrations of GTC inhibits tension by K or norepinephrine GTC may have Ca2+ channel activation, action, which may result in unphysiological vasodilation by Ca2+ overload in vascular smooth muscle.