• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.12
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• pp.88-93
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• 2011

When the ground current is injected into the adjacent ground electrode, the potential interference is caused between ground electrodes, the ground potential interferences have been largely studied with power frequency fault currents. Many attempts to find the frequency-dependent grounding impedance report that the high frequency grounding impedance is very different with the ground resistance. This paper presents experimental data on the frequency-dependent potential interference effects in the vicinity of ground rod. The ground potential rises around the test ground rod of 4 or 6[m] were measured and discussed. As a result, the ground potential rises and potential interference factor are decreased with decreasing the grounding impedance. It was found that the lowering of grounding impedance is critical to reduce the ground potential interference effects.

• Wind and Structures
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• v.9 no.3
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• pp.245-254
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• 2006

The pressure and drag measurements were carried out in the wind tunnel to investigate the drag reduction of the disk by using an interference rod placed upstream. The results indicate that there is a pair of standing vortices in the front stagnation region of the disk induced by the rod. The standing vortices can decrease the pressure on the disk upwind side; hence it can reduce the drag of the disk. With an increasing rod diameter, the standing vortices are strengthened and more drag reduction can be achieved for the disk. With rod diameter d/D = 0.05 (d, D are the diameters of rod and disk, respectively), the total drag of the disk can be reduced by about 9% compared with that of the bare disk.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.351-354
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• 2006

This paper deals with the potential interferences between ground rod and counterpoise. The ground potential rise and coefficient of potential interference were measured by using the hemispherical water tank grounding simulator and calculated from CDEGS program as functions of the configuration and size of grounding electrodes and the distance between grounding electrodes. The ground potential un and potential interference coefficient strongly depend on the distance between grounding electrodes, the arrangement and size of grounding electrodes.

• Applied Microscopy
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• v.50
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• pp.11.1-11.3
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• 2020

The human turbinate-derived mesenchymal stem cells (hTMSCs), which were DiI-labeled and transplanted into the subretinal space in degenerating mouse retina, were observed in retinal vertical sections processed for rhodopsin (a marker for rod photoreceptor) by confocal microscope with differential interference contrast (DIC) filters. The images clearly demonstrated that DiI-labeled hTMSCs have rhodopsin-immunoreactive appendages, indicating differentiation of transplanted hTMSC into rod photoreceptor. Conclusively, the finding suggests therapeutic potential of hTMSCs in retinal degeneration.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.12
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• pp.107-112
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• 2011

Multiple ground rods are commonly used to obtain the low ground impedance, but they will not reduce the ground impedance unless the spacings between the ground rods are sufficient. This paper presents the experimental results of frequency-dependent resultant ground impedance of two ground rods in parallel. The resultant ground impedance of two ground rods in parallel were measured as functions of the spacing and length of ground rods and the frequency of test currents and were discussed based on the potential interferences. As a consequence, the frequency-dependent ground impedance of single ground rod and two combined ground rods give capacitive. It was found that the effect of potential interference on the ground impedance is directly associated with the frequency-dependent ground impedance and is strong in low frequency. Also, in order to reduce the increasing rate of resultant ground impedance of two ground rods due to potential interference to within 10(%), two ground rods in parallel will be placed over one rod length apart.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.204-209
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• 1990

The temperature variation at a laser rod center induced by high repetetion rate pumping was measured by counting the number of inteference frigne shift and found to be consistent with the theoretical value obtained from heat diffusion equation. The spatial homogeneity and energy transfer rate of flashlamp pumping by the single elliptical reflector plated with gold were evaluated by measuring interference fringes oever the cross section of a Nd:YAG laser rod.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.11a
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• pp.261-263
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• 2005

This paper presents the potential interferences between various grounding electrodes. The ground potential rise and potential interference coefficient between grounding grid and ground rod were calculated. The potential rise and potential interference coefficient strongly depend on the distance between grounding electrodes.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.10
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• pp.1651-1658
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• 2001

It is necessary to evaluate fatigue strength and reliability of the connecting rod which is core part in automotive engine to assure the high level of durability of automobile. For this purpose, the loading conditions in automotive engine is obtained by the dynamic analysis. Based on these results, the critical section was identified by the finite element analysis. The fatigue strength under constant amplitude was evaluated and the mean of the fatigue limit at R = -2.27 derived from the staircase method was 311.2MPa. And the failure probability( F$\sub$p/ ) derived from the strength-stress interference model is 0.0003% at the 99.99% confidence level and the mean factor of safety was 4.2.

• Applied Microscopy
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• v.39 no.4
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• pp.291-299
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• 2009

We report on a quantitative analysis of cone and rod photoreceptors in hamster retina. Cone and rod photoreceptors were counted in retinal whole mounts using differential interference contrast (DIC) optics microscopy after staining of cone photoreceptors were stained with peroxidase-labeled peanut lectin. Middle-to-long-wave-sensitive-(M/L-), and shortwave-sensitive-(S-) cone opsins were visualized by observed using confocal microscope after immunocytochemical procedure. The average cone density was 9,307 $cells/mm^2$, giving a total of cones of 293,060 cone cells per retina. The peak density of cone cells (12,857 $cells/mm^2$) was found 0.3 mm from the optic disk (OD) of the nasal retina. The average rod density was 300,082 $cells/mm^2$, giving a total number of rods of 9,448,150 cells. The peak density of rod cells was found 0.3 mm from the OD of the dorsal retina. Of all photoreceptors studied, the total percentage of rods and cones were 96.99% and cones 3.01%, respectively. The mean ratio of rod and cone was 32.24 : 1. The cone photoreceptors of hamster contained both M/L- and S-cone opsins. The present results suggest that the hamster retina is strongly rod-dominated with some photopic property of vision.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.345.2-345
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• 2002