• Journal of Environmental Science International
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• v.12 no.6
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• pp.615-626
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• 2003

The applied model for this study area is WINFLOW using mite element method, It is thought that the simulation result by WINFLOW model under the steady flow state reflects well the ground water distribution within the reliability level which shows the error range of 1.1% to 8.0% from the comparison between the computed values and the observed, and analyzed that the constant head distribution is shown along the east-west direction and gentle and stable head gradient along the north-south direction. Ground water of the study area shows stable movement from the south to the stream area, and the particle trace for each location shows relatively linear shape from the upstream to the pumping location while the radius of influence according to the pumping amount shows a significant difference at the down stream area from the pumping location. The simultaneous pumping from P and P1 shows more complicated appearance, not the increase of the radius of influence than pumping from a single well P or P1, and it is analyzed that the particle path takes nearly linear form. It is known that the flow direction of the ground water and the velocity of the flow affect on the magnitude of the radius of influence of the wells from the fact that the more decreasing pattern of the ground water head is observed at the side of the well and the down stream area than the upstream area when the ground water moves from south to north regarding the radius of influence according to the pumping amount. Satisfactory results in analyses of ground water movement are obtained through the significant reduction of the physical uncertainties in the flow system as well as the relatively convenient model application using WINFLOW model which is proposed in this study.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.1
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• pp.43-55
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• 2008

The complexity of determining strain associated with shear modulus and damping ratio in torsional tests has been resolved by means of several approaches. Particularly, the modified equivalent radius approach is adequate to when generating the plots of equivalent radius ratio versus strain more effectively over any range of strains in resonant column and torsional shear (RC/TS) tests. The modified equivalent radius approach was applied for hyperbolic, modified hyperbolic, and Ramberg-Osgood models in evaluating damping ratio. Results showed that using a single value of equivalent radius ratio based on conventional equivalent radius approach is not appropriate. A new model was developed to consider the soil damping behavior at small strains as well as hysteretic damping and it was attempted to determine adjustments are required in evaluating strain associated damping when combining the two damping components.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.4
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• pp.34-43
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• 2012

The behaviors of the curved bridges which has been constructed in the RAMP or Interchange are very complicate and different than orthogonal bridges according to the variations of radius of curvature, skew angle and spacing of shoes. Occasionally, the camber of girder and negative reactions can be occurred due to bending and torsional moment. In this study, the effects on the negative reaction in the curved bridge were investigated on the basis of design variables such as radius of curvature, skew angle, and spacing of shoes. For this study, the twin-steel box girder curved bridge with single span which is applicable for the RAMP bridges with span length(L) of 50.0m and width of 9.0m was chosen and the structural analysis to calculate the reactions was conducted using 3-dimensional equivalent grillage system. The value of negative reaction in curved bridges depends on the plan structures of bridges, the formations of structural systems, and the boundary conditions of bearing, so, radius of curvature, skew angle, and spacing of shoes among of design variables were chosen as the parameter and the load combination according to the design standard were considered. According to the results of numerical analysis, the negative reaction in curved bridge increased with an decrease of radius of curvature, skew angle, and spacing of shoes, respectively. Also, in case of skew angle of $60^{\circ}$ the negative reaction has been always occurred without regard to ${\theta}/B$, and in case of skew angle of $75^{\circ}$ the negative reaction hasn't been occurred in ${\theta}/B$ below 0.27 with the radius of curvature of 180m and in ${\theta}/B$ below 0.32 with the radius of curvature of 250m, and in case of skew angle of $90^{\circ}$ the negative reaction hasn't been occurred in the radius of curvature over 180m and in ${\theta}/B$ below 0.38 with the radius of curvature of 130m, The results from this study indicated that occurrence of negative reaction was related to design variables such as radius of curvature, skew angle, and spacing of shoes, and the problems with the stability including negative reaction will be expected to be solved as taken into consideration of the proper combinations of design variables in design of curved bridge.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.54-64
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• 1995

The effects of swirl on early flame development and late combustion characteristic were investigated using a high speed single-shot visualized 51 engine. LDV measurements were performed to get better understanding of the flow field in this combustion chamber. Spark plugs were located at half radius (R/2) and central location of bore. High speed schlieren photographs at 20,000 frames/sec were taken to visualize the detailed formation and development of the flame kernel with cylinder pressure measurements. This study showed that high swirl gave favorable effects on combustion-related performances in terms of the maximum cylinder pressure and flame growth rate regardless of spark position. However, at R/2 ignition the low swirl shown desirable effects at low engine speed gave worse performances as engine speed increased than without swirl. There were distinct signs of slow-down in flame growth during the period when the flame front expanded from 2.5mm in radius until it reached 5.0mm apparently due to the presence of ground electrode. There seemed to be heat transfer effect on the flame expansion speed which was evidenced in high swirl case by the slowdown of the late flame front presumably caused by relatively large heat loss from burned gas to wall compared with low- or no-swirl cases.

• Journal of Life Science
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• v.16 no.5
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• pp.773-779
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• 2006

Eight of the individuals had a unilateral S-RAD TKA and Multi-Radius TKA ($Scorpio^{TM}$ PS, Howmedica-Osteonics, Inc.). The instrument were used Peak Motion Measurement $System^{TM}$, $MYOPAC^{TM}$EMG System, KIN-COM $III^{TM}$ System. The Figure 3 shows that the average time for the S-RAD group to accomplish the sit-to-stand movement was 1.59 s, which was 0.19 s less than the M-RAD group (p= 0.033). In Figure 5, the S-RAD TKA group tended to have $7^{\Omega}{\cdot}S^{-1}$ less trunk flexion velocity than that of the M-RAD group (p= 0.058). The Figure 6 shows that the S-RAD TKA limb tended to have less ADD displacement (p = 0.071) than that of the M-RAD TKA limb. We failed to find significant differences for ABD and ADD displacements between the S-RAD and M-RAD N-TKA limbs (p= 0.128 and 0.457, respectively). The VM of the S-RAD TKA limb demonstrated significant less RMS EMG than that of the M-RAD TKA limb from $60^{\Omega}$ to $15^{\Omega}$ of knee flexion (p 0.05). The VL of the S-RAD TKA limb also demonstrated significant less RMS EMG than that of the M-RAD TKA limb from $60^{\Omega}$ to $45^{\Omega}$ of knee flexion (p 0.05). Similar to the VM and VL, the RF of the S-RAD TKA limb showed less RMS EMG than that of the M-RAD TKA limb from $60^{\Omega}$ to $30^{\Omega}$ of knee flexion (p 0.05).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.326-331
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• 2007

This paper conducts a vibratory loads reduction analysis of an Advanced Active Trailing-edge Flap (AATF) blade utilizing single crystal piezoelectric actuators. For an AATF blade, a new L-L piezostack actuator using single crystal PMN-PT materials is designed. The AATF blade is designed to have similar characteristics to the Advanced Active Twist Rotor (AATR) blade. The active trailingedge flap is assumed to be 20% of the blade span and 15% of the chord, located at 75% of the blade radius. In order to conduct the vibratory loads reduction analysis of the AATF blade in forward flight, DYMORE, a multi-body dynamics analysis code, is used. The simulation result shows that the hub vibratory loads may be reduced by approximately 89% even with a much lower input-voltage when comparing with the other active rotor systems.

• JSTS:Journal of Semiconductor Technology and Science
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• v.11 no.2
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• pp.80-87
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• 2011

Low temperature hole transport characteristics of gate-all-around p-channel metal oxide semiconductor (PMOS) type silicon nanowire field-effect-transistors with the radius of 5 nm and lengths of 44-46 nm are presented. They show coexisting two single hole states randomly switching between each other. Analysis of Coulomb diamonds of these two switching states reveals a variety of electrostatic effects which is originated by the potential of a single hole captured in the trap near the nanowire.

• Journal of The Korean Astronomical Society
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• v.32 no.1
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• pp.17-39
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• 1999

We investigate dynamical evolution of globular clusters with multi-mass component under the Galactic tidal field. We compare the results with our previous work which considered the cases of single-mass component m the globular clusters. We find the followings: 1) The general evolutions are similar to the cases of single-mass component. 2) There is no evidence for dependence on the orbital phase of the cluster as in the case of single-mass component. 3) The escape rate in multi-mass models is larger than that in the single-mass models. 4) The mass-function depends on radius more sensitively in anisotropic models than in isotropic models.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.1
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• pp.57-63
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• 1991

In this paper, propagation characteristics of W-type single mode fiber with dual shape core is investigeted theoretically. Design parameters of DSC(dual shape core) W-type single mode fiber with very low dispersion over a wide wavelength range are computed using scalar approximation. The results have larger core radius and stronger confinement for mode field distribution in core than conventional W-type fiber with single shape core.

• Journal of Veterinary Science
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• v.21 no.4
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• pp.62.1-62.7
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• 2020

A 5-month old Shih Tzu was diagnosed with congenital elbow luxation and uniapical complex angular deformity of the radius. Single radial oblique and dynamic ulnar osteotomies were performed, using patient-specific 3D-printed osteotomy guide. External skeletal fixation was maintained for three weeks to prevent re-luxation of elbow joint. Three months after the surgery, objective gait analysis indicated markedly improved limb function. In addition, radiograph showed improved congruity of elbow joint and appropriate bone healing. In dogs with congenital radial head luxation and concurrent complex angular deformity, a single oblique osteotomy might be a viable option to preserve bone length and correct the luxation of elbow joint.