• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.137-146
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• 1999

The SSI(Soil-Structure Interaction) analyses are being performed for the KNGR(Korean Next Generation Reactor) design because the KNGR is developed as a standard nuclear power plant concept enveloping various soil conditions. the SASSI program which adopts the flexible volume method is used for the SSI analyses. The soil curves used in the three dimensional SSI analyses of KNGR Nuclear Island(NI) structures are based on the upper bound shear modulus curve and lower bound damping degradation on SSI response the average shear modulus curve with average damping curve was used for two soil cases. This study presents the results of the variances by using different soil nonlinearity parameters based on the paametric SSI analyses. The results include the maximum member forces(shear and axial force) at the base of the NI structures and the 5% damping Floor Response Spectra (FRS) at some representative locations at the top of the NI superstructures. They are also compared together with the enveloped SSI results for eight soil cases and fixed-base analysis for rock case by using two control motions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.3 no.1
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• pp.83-95
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• 1974

This experiment was initiated to determine the effective components of garlic during the growth stages and to regulate the contents artificially. The following results were obtained : 1. Alliin content was increased during its growth and showed drastic increase at maturing stage. 2. The kinds of free amino acids detected during growth stages were 15 for leaf growth, 14 for bulbing and 18 for maturing stage. The total content of free amino acids was high. est at maturing stage. 3. The optimum conditions for the maximum amounts of alliin and free amino acid determined by the binary interaction of Systematic Variations Method were 40% $NO_3^{-1}+60%\;SO_4^{-2}$, 62% $NO_3^{-1}+38%\;PO_4^{-3}$, 42% $K^{+1}+58%\;Ca^{+2}$ and 56% $K^{+1}+44%\;Mg^{+2}$ for alliin, and 72% $NO_3^{-1}+28%\;SO_4^{-2}$, 49% $NO_3^{-1}+51%\;SO_4^{-2}$, 45% $K^++55Ca^{+2}$ and 66% $K^{+1}+34%\;Mg^{+2}$ for free amino acid. 4. Ideal curve for alliin and free amino acid was attained by applying the binary interaction of Systematic Variations Method and it was possible to approach the optimum ionic proportion from the optimum contents on this curve.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.8
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• pp.100-107
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• 2002

The extruder screw is a part for extruding material in a injection molding machine. The screw's geometrical shape can mathematically be described by a sweep surface which is constructed by sweeping a section curve composed of a few circular arcs, along a helical guide curve. In the paper we developed a dedicated CAD system which basically is parametric in a sense that the system initially takes several design parameters to construct the geometric elements including the final sweep surface of the screw as well as section & guiding curves, along with feasibility check of the input parameter values, without further user interaction. The system has been developed as a built-in module onto a commercial CAD system, which can further incorporate additional NC-out functions with ease.

• Structural Engineering and Mechanics
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• v.66 no.2
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• pp.151-160
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• 2018

With the aim to evaluate the fatigue damage accumulation and predict the residual life of engineering components under variable amplitude loadings, this paper proposed a new strain energy-based damage accumulation model by considering both effects of mean stress and load interaction on fatigue life in a low cycle fatigue (LCF) regime. Moreover, an integrated procedure is elaborated for facilitating its application based on S-N curve and loading conditions. Eight experimental datasets of aluminum alloys and steels are utilized for model validation and comparison. Through comparing experimental results with model predictions by the proposed, Miner's rule, damaged stress model (DSM) and damaged energy model (DEM), results show that the proposed one provides more accurate predictions than others, which can be extended for further application under multi-level stress loadings.

• Steel and Composite Structures
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• v.5 no.5
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• pp.375-394
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• 2005

An experimental study was conducted to develop a new base plate anchorage system for concrete filled tubular column under an axial load and a moment. The column was connected to a concrete foundation using ordinary deformed reinforcing bars that are installed at the inside and outside of the column. In order to investigate the moment resisting capacity of the system, horizontal cyclic loads are applied until the ultimate condition is reached with the axial load held constant. To derive a design method for moment resisting capacity, the reinforced concrete section approach was investigated with the assumption of strain compatibility. The results by this approach agreeded well with those of experiments when the bearing pressure of confined concrete and tangent modulus of steel bars are assumed appropriately. Also, it was found that the column interaction curve can be used to predict the yield strength of the base plate system.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.294-306
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• 2019

On the basis of the Computational Fluid Dynamics technique (CFD) combined with the overlap grid method, this paper establishes a numerical simulation method to study the problem of ice-propeller interaction in viscous flow and carries out a simulation forecast of the hydrodynamic performance of an ice-class propeller and flow characteristics when in the proximity of milling-shape ice (i.e., an ice block with a groove cut by a high-speed revolving propeller). We use a trimmed mesh in the entire calculation domain and use the overlap grid method to transfer information between the domains of propeller rotation calculation and ice-surface computing. The grid is refined in the narrow gap between the ice and propeller to ensure the accuracy of the flow field. Comparison with the results of the experiment reveals that the error of the hydrodynamic performance is within 5%. This confirms the feasibility of the calculation method. In this paper, we calculate the exciting force of the propeller, analyze the time domain of the exciting force, and obtain the curve of the frequency domain using a Fourier transform of the time-domain curve of the exciting force. The existence of milling-shape ice before the propeller can greatly disturb the wake flow field. Unlike in open water, the propeller bearing capacity shows a downward trend in three stages, and fluctuating pressure is more disordered near the ice.

• Journal of Pharmaceutical Investigation
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• v.27 no.1
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• pp.51-56
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• 1997

This study was attempted to investigate the pharmacokinetic interaction of vancomycin (10 mg/kg, i.v.) and probenecid (7.5. 15, and 30 mg/kg, oral) in rabbits. The area under curve (AUC) of plasma vancomycin concentration was significantly increased (p<0.01) in rabbits when the probenecid was coadministrated. Volume of distribution (Vd) was significantly decreased (p<0.05) in rabbits coadministrated with probenecid (15 and 30 mg/kg) and total body clearance (CLt) was decreased significantly (p<0.05. p<0.01) in rabbits coadministrated with probenecid (7.5, 15 and 30 mg/kg). There was significant correlation between AUC and probenecid dose. From the results of this experiment, it is desirable to adjust dosage regimen of vancomycin for reduction of side or toxic effect when the probenecid is coadministered in clinical practice.

• Journal of Pharmaceutical Investigation
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• v.26 no.2
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• pp.113-117
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• 1996

This study was attempted to investigate the pharmacokinetic interaction between sodium valproate (4, 8, 16 mg/kg, i.v.) and phenytoin (4 mg/kg, i.v.) in rabbits. The plasma concentration and area under the curve (AUC) of phenytoin were increased significantly (p<0.05, p<0.01) when coadministered with sodium valproate (4, 8, 16 mg/kg) in rabbits. The volume or distribution and total body clearance of phenytoin were decreased significantly (p<0.05, p<0.01) when coadministered with sodium valproate (8, 16 mg/kg) in rabbit. From the results of this experiment, it is desirable that dosage regimen of phenytoin should be adjusted and therapeutic drug monitoring should be performed for reduction of side or toxic effect when phenytoin will be coadministered with sodium valproate in clinical use.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.109-114
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• 2003

It is the common practice to reinforce excessively the secondary tunnel lining due to the lack of rational insights into the ground loosening loads. The main load of the secondary lining for drained-type tunnels is the ground loosening. The main cause of the load for secondary tunnel lining is the deterioration of the primary support members such as shotcrete, steel ribs, and rockbolts. Accordingly, the development of the analysis model to consider the ground-primary supports-secondary lining interaction is very important for the rational design of the secondary tunnel lining. In this paper, the interaction is conceptually described by the simple mass-spring model and the load transfer from the primary supports to the ground and the secondary lining is showed by the characteristic curves including the secondary lining reaction curve for the theoretical solution of a circular tunnel. And also, the application of this model to numerical analysis is verified in order to review the potential tool for practical tunnel problems with the complex conditions like non-circular shaped tunnels, multi-layered ground, sequential excavation and so on.

• Earthquakes and Structures
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• v.13 no.1
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• pp.39-50
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• 2017

Displacement response and corresponding maximum response energy of structures are key parameters to assess the dynamic effect or even more destructive structural damage of the structures. By employing them, this research has compared the structural responses of jacket supported offshore wind turbine (OWT) subjected to seismic excitations apprehending earthquake incidence, when (a) soil-structure interaction (SSI) has been ignored and (b) SSI has been considered. The effect of earthquakes under arbitrary angle of excitation on the OWT has been investigated by means of the energy based wavelet transformation method. Displacement based fragility analysis is then utilized to convey the probability of exceedance of the OWT at different soil site conditions. The results show that the uncertainty arises due to multi-component seismic excitations along with the diminution trend of shear wave velocity of soil and it tends to reduce the efficiency of the OWT to stand against the ground motions.