• Journal of Life Science
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• v.26 no.11
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• pp.1253-1258
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• 2016

Although major advances have been achieved in our understanding and treatment of diseases in many areas of medicine, relatively few improvements have been made in the area of gastrointestinal (GI) motor function. The dried root of Codonopsis pilosula (Franch.) Nannf. (CP) has been used as a traditional folk medicine for improving poor GI function in East Asia, including China and Korea. In the present study, neither aqueous (CP-W) nor ethanolic (CP-E) extracts of CP showed significant toxicity, even at an oral dose of 5 g/kg to mice. The effects of CP-W and CP-E on GI motor function were investigated by measuring in vivo the gastric emptying rate (GER) and intestinal transit rate (ITR) in mice. In normal mice, the ITR was significantly increased by CP-W in a dose-dependent manner, whereas the GER was not significantly affected by any CP extracts. The ITR was significantly retarded in the mice with experimental GI motility dysfunction (i.e., peritoneal irritation by acetic acid) compared with that in normal mice. However, the retardation was significantly recovered by the pre-treatment of CP-W in a dose-dependent manner. The above results suggest that CP-W might be a potential prokinetic agent preventing or alleviating GI motility dysfunctions in human patients.

• Journal of Life Science
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• v.29 no.6
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• pp.735-739
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• 2019

The dried rhizomes and roots of Gentiana scabra (GS) have been frequently prescribed as a traditional folk medicine in East Asia (including China, Japan, and Korea) for the treatment of various pathophy-siological conditions, such as inflammatory skin diseases, anorexia, indigestion, gastric infections, and diabetes mellitus. In the present study, the effects of aqueous (GS-W) and ethanolic (GS-E) extracts of GS on gastrointestinal (GI) motor function were investigated by measuring the in vivo gastric emptying rate (GER) and the intestinal transit rate (ITR) in mice. The GER was significantly increased by GS-W at a dose of 1 g/kg. The ITR was significantly increased by GS-W (at doses of 0.1 and 1 g/kg) or GS-E (at a dose of 1 g/kg) in a dose-dependent manner. Furthermore, the ITR value of GS-W (at a dose of 1 g/kg) appeared to be higher than that of cisapride, which was the most prominent prokinetic agent in the 1900s but was removed from the market in 2000 due to its fatal side effects. The above results suggest that GS-W might be a potential prokinetic agent to replace cisapride.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.457-458
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• 2009

• Journal of the Society of Naval Architects of Korea
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• v.45 no.6
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• pp.688-694
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• 2008

The reduction of the structure-borne noise is very important in order to reduce the noise of a ship. The noise at the high frequency range usually comes from the fluid flowing. The noise from the sea-water conveying pipe is one of the main source on these high frequency range. Therefore, the transmissibility variations are evaluated according to the shape of the rubber mount. The evaluations are performed with the frequency response function numerically and experimentally.

• Proceedings of the KTCVS Conference
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• 1998.10a
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• pp.201-201
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• 1998

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.4
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• pp.35-43
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• 2016

Recently, the pipeline system for waste transportation has been increasingly constructed as new solution for the waste collection and disposal system by constantly increasing domestic waste which issued as social problem. The pipeline system is constructed through long distance, so proper long-term monitoring system is necessary which available to detect the damage location for the effective maintenance. In this paper, the experimental study is carried out to evaluate the applicability of optical strain gauge sensor based on FBG for the long-term monitoring system. Three test parameters such as pressure leaking, blockage and deformation are considered as typical damages for real-scale pipeline test specimen. In order to measure flexural and volumetric strain and temperature, three FBG sensors are installed at each monitoring sections. From the test results, this study suggested effective methods of sensor installation and arrangement. Also the sensor spacing for the design of monitoring system using FBG sensor is derived by the correlation of distances from deformation between sensor responses.

• Journal of Korea Water Resources Association
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• v.38 no.3 s.152
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• pp.223-233
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• 2005

In this study, a two-dimensional model for identifying areas of erosion and deposition over a basin was developed based on the mass balance principle in a distributed model. The program consists of three steps: (a) estimation of soil erosion; (b) determination of flow amount and direction; and (c) estimation of mass balance. Soil erosion was estimated with USLE. A single-direction (SF) and a multi-direction flow algorithm (MF) were applied to estimate slope length (L). The Maximum Downhill Slope Method (MDS) and the Neighborhood Method (NBH) were used to estimate the slope degree (S). Sediment transport resulting from eroded soil was estimated using Ferro's (1998) and Swift's (2000) sediment delivery ratio (DR). The model was validated by comparing the predicted sediment yields for three basins with measured data. The developed algorithm showed that Ferro's DR method combined with the MDS and MF produced the best agreement with the dredging records of three agricultural reservoir basins in Korea.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.5
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• pp.320-333
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• 2019

In this study, a physics-based 3D morphology model for the estimation of an erosion rate of nourished beach is newly proposed. As a hydrodynamic module, IHFOAM toolbox having its roots on the OpenFoam is used. On the other hand, the morphology model comprised a transport equation for suspended sediment, and Exner type equation derived from the viewpoint of sediment budget with the bed load being taken to accounted. In doing so, the incipient motion of sediment is determined based on the Shields Diagram, while the bottom suspended sediment concentration, the bed load transport rate is figured out using the bottom shearing stress directly calculated from the numerically simulated flow field rather than the conventional quadratic law and frictional coefficient. In order to verify the proposed morphology model, we numerically simulate the nonlinear shoaling, breaking over the uniform beach of 1/m slope, and its ensuing morphology change. Numerical results show that the partially skewed, and asymmetric bottom shearing stresses can be successfully simulated. It was shown that sediments suspended and eroded at the foreshore by wave breaking are gradually drifted toward a shore and accumulated in the process of up-rush, which eventually leads to the formation of swash bar. It is also worth mentioning that the breaker bar formed by the sediments dragged by the back-wash flow which commences at the pinnacle of up-rush as the back-wash flow gets weakened due to the increased depth was successfully duplicated in the numerical simulation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.04a
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• pp.187-187
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• 2019

• Journal of the Society of Naval Architects of Korea
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• v.46 no.3
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• pp.290-302
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• 2009

Pipe system widely used in a ship is usually attached to the hull of a ship, and its vibration lead to structure-borne noise. Rubber mount is usually used as a vibration isolator of a pipe in a ship. In this paper, the effects of several factors, besides the stiffness and damping of the rubber mount, on vibration-isolating performance are taken into consideration. The parameters considered in this paper are hardness of the rubber material, painting on the rubber and deformation from clamping. Through the results of parametric study, the effective specifications of rubber mount are suggested to improve vibration-isolating performance. The performance under fluid flowing condition is calculated numerically and verified experimentally.