• Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.183-190
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• 2002

To determine the effect of body size on the clearance rate and ingestion rate of small intertidal bivalves, Glauconome chinensis, feeding experiments were conducted on individuals of 12 different size classes, from 4 to 16 mm in shell length. Relationships between morphological parameters were also determined. The clearance and ingestion rates of G. chinensis responded similarly to their body size, ranging from 1.3 to 28.2 mL/hr/ind. and from 24.0 to 458.5, ${\mu}gC/hr/ind$., respectively. Both rates increased significantly (p<0.001) as shell length increased from 4 to 9 mm, although neither rate changed significantly when shell length was in the range from 12 to 16 mm. The weight-specific clearance rate $(CR_w)$ and ingestion rate $(IR_w)$ decreased with increasing body size, with values from 1.0 to 3.1 L/hr/g and from 17.9 to 51.3 mgC/hr/g, respectively. The $CR_w$ of G. chinensis was intermediate compared to those of larger bivalve species. The clearance rate (CR) relative to flesh dry weight (FDW) of G. chinensis were fitted well to the power function: $CR=0.43\times(FDW)^{0.71}\;(r^2=0.89)$. The exponent of fitting equation (0.71) of G. chinensis was higher than those of Mytilus edulis (Walne, 1972), Crassostrea gigas (Walne, 1972), and Placopecten magellanicus (MacDonald and Thompson, 1986).

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.6
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• pp.289-299
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• 2019

The tendency to use a probabilistic design method rather than a deterministic design method for the design of nuclear power plants (NPPs) will increase because their safety should be considered and strictly controlled in relation to various causes of damage. The distance between a seismically isolated NPP structure and a moat wall is called the clearance to stop. The clearance to stop is obtained from the 90th percentile displacement response of a seismically isolated NPP subject to a beyond design basis earthquake (BDBE) in the probabilistic design method. The purpose of this study is to analyze the effects of heating and buckling effects on the 90th percentile displacement response of a lead-rubber bearing (LRB) subject to a BDBE. The analysis results show that considering the heating and buckling effects to estimate the clearance to stop is conservative in the evaluation of the 90th percentile displacement response. If these two effects are not taken into account in the calculation of the clearance to stop, the underestimation of the clearance to stop causes unexpected damage because of an increase in the collision probability between the moat wall and the seismically isolated NPP.

• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.263-272
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• 2018

Purpose: The load on the planet gear of a planetary gear set is uniformly distributed. However, manufacturing and assembly errors cause uneven load sharing in the planetary gear set. To solve this problem, most studies have suggested applying a floating sun gear to the planetary gear set. However, the effect of the floating ring gear and floating carrier has not been extensively studied. This study aimed to investigate the effect of the floating ring gear. Methods: Two models were developed; one was the fixed ring gear model, and the other was the floating ring gear model. In the fixed ring gear model, the clearance between the ring gear and the housing was $0{\mu}m$, and in the floating ring gear model, the clearance was from $10{\mu}m$ to $100{\mu}m$. The load sharing of the planetary gear set was evaluated by the load sharing factor. Results: Our study showed that with increase in clearance, the load sharing factor of the planetary gear set approached unity. In addition, when the clearance increased above a certain level by which a fully floating ring gear was achieved, the load sharing factor was not affected by the clearance. Conclusions: This indicates that the fully floating ring gear increased the power density of the planetary gearbox by uniformly dividing the load of the planetary gear set. For this reason, the size of the gearbox could be decreased by using a fully floating ring gear.

• Journal of Ginseng Research
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• v.21 no.1
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• pp.49-52
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• 1997

There are many mechanisms that mediate progression of renal injury, such as abnormalities of nitric oxide (NO) regulation, increased Platelet aggregatlon, and oxygen free radical injury. Ginseng has been known to have NO dependent vasorelaxant effect and antioxidant effect, also inhibit thrombin stimulated platelet aggregation. And these effects of ginseng may have some roles in prevention of renal injury. So we studied 24 patients with mild pathologic proteinuria and hypertension to evaluate the effect of ginseng on progression of renal injury. After 1 month treatment, creatinine clearance was significantly increased especially in the patient group with normal serum creatinine level without specific side effect. The result of this study suggest that ginseng may pre vent or retard the progression of renal injury especially in early stage.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.5
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• pp.142-151
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• 2005

To predict the fatigue life of the Hub Bearing Unit(HBU), preload effect and initial axial clearance have to be considered. Various theory and equations for the HBU design used in the passenger car are well developed in many literatures. But most design hand book for bearings or bearing catalogues do not consider the initial axial clearance and preload effect. So there are limits and difficulties to use those data in actual bearing design. To consider the preload effect and initial axial clearance, complex elliptic integrals and nonlinear equations are involved. These equations are difficult to solve during the design process. In order to solve these problems effectively, a program is developed to solve these equations reliably and to help the designer in obtaining the performance data of the HBU such as load distribution, maximum contact stress and fatigue life. The preprocessor of the program helps users to prepare the input data through a dialog box and the post processor makes graphical presentation of the result. In this paper, theoretical and numerical background for the prediction of the fatigue life of the HBU is explained. A simple example is presented to show the usefulness of developed program.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.441-454
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• 2018

Since the permanent shutdown of Kori Unit 1 in 2017, a full-scale decommissioning project for a commercial nuclear reactor has been approaching. It is estimated that about 160,000 t of low-activity concrete waste will be produced from decommissioning of one unit of this commercial nuclear power reactor. Accordingly, it is necessary to review whether the effectiveness of the current regulatory framework for clearance waste (i.e. waste stream that meets activity concentration guidelines or dose criteria for clearance set forth in NSSC Notice No. 2017-65) can be maintained for the clearance of a bulk amount of concrete waste. In this regard, the IAEA SRS No. 44, which was used as a basis for revision of the Korean clearance regulations, is thoroughly analyzed and the radiological effects from four different clearance scenarios, along with input values and parameters derived from industrial practices in Korea, were evaluated. Though it is shown that the maximum annual dose from most recycling scenarios will be less than the clearance dose criterion for the normal scenario (i.e. an order of magnitude of $0.01mSv{\cdot}y^{-1}$), the radiation dose, estimated with conservative assumptions for the banking scenario, may exceed the above clearance dose criteria. Therefore, for safe and sustainable clearance of the bulk amount of concrete waste, it is required to diversify the concrete waste processors, perform more detailed site-specific assessment, and apply limiting conditions to the banking scenario.

• Journal of Ocean Engineering and Technology
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• v.12 no.2 s.28
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• pp.87-96
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• 1998

A numerical simulation was done to investigate the performance of thin wings in close vicinity to ground. The simulation is based on Vortex Lattice Method(VLM) and freely deforming wake elements are taken into account for a sudden acceleration case. The parameters covered in the simulation are angle of attack, aspect ratio, ground clearance, sweep angle and taper ratio. In addition, the effect of the wing endplate on the ground effect is included. The wing sections used for present computations are uncambered, cambered and S-types. The present computational results are compared with other published computational results and experimental data.

• The Journal of Korean Medicine
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• v.23 no.2
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• pp.28-38
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• 2002

Objectives : This study was to examine the efficacy of GCT on the hepatoprotective effect in the liver function and immune octivity. Methods : The experiment to investigate the hepatoprotective effect of GCT on the liver damage was conducted with D-galactosamine. The experiments to verify the effects of GCT on the immune activity were conducted by carbon clearance assay, plaque-forming cell SRBC assay of IgM, lymphoproliferation assay of T and B cells, and adherence and phagocytosis of mocrophages. Results: In the damage of liver induced by D-galactosamine, GCT carried hepatoprotective effect on AST. In carbon clearance assay GCT showed significant effect on phagocytosis of Kuffer cells. In the plaque-forming cell assay, GCT improved the formation of IgM. In the lymphoproliferation assay, GCT activated the formation of T and B lymphocytes. In macrophages, GCT activated adherence and phagocytosis. Conclusion : Though further study is needed, our findings suggest that GCT could be recommended as hepatoprotector and immune modulator for liver disease.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1440-1443
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• 2004

Shearing including punching, blanking, trimming, slitting, etc is one of the most frequently used processes in sheet metal manufacturing. It has been widely used for manufacturing autobody, electronic components, aircraftbody, etc. In this paper, it has been researched by the experiment to examine the effect of burr height corresponding to die clearance, cutting angle, tool sharpness, etc. This paper presents the experimental results with using Al alloy sheet.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.10a
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• pp.217-224
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• 1997

Static characteristics of hemispherical aerodynamic bearing is studied theoretically. In this paper nonlinear equation of second order considering compressibility and slip effect of air is calculated by Newton-Raphson method. Results indicate that axial load capacity has maximum value when the inclination angle of groove is about 30$\circ$, the ratio of groove clearance to ridge clearance is two. We also present the design method of hemispherical Aerodynamic bearing based on it's load capacity taking into account manufacturing and assembling viewpoint.