• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.396-399
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• 2003

This paper proposes a simple digital image stabilization(DIS) algorithm for roll motion, which has not been compensated in the 2-axes mechanical stabilization system, using aero-crossing of the rotational motion vectors. The 2-axes stabilization system cannot stabilize rolled images, which causes the deteriorated performance of the object detection and recognition. In this paper, we propose the rotational motion stabilization algorithm which estimates and compensates global motion in terms of rotational center and rotational angle. Both the synthetic images with undesirable rotational disturbance and the real images from 2-axes stabilization system are used to evaluate the proposed algorithm. The results show that our proposed algorithm suppresses the undesirable rotational disturbance effectively.

• Earthquakes and Structures
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• v.16 no.6
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• pp.665-677
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• 2019

This study utilizes large-scale shake table test to investigate the seismic performance of an isolated bridge with lead rubber bearings crossing an active fault. Two transverse restraining systems with and without shear keys are tested by applying spatially varying ground motions. It is shown that the near-fault span exhibits larger bearing displacement than the crossing-fault span. Bridge piers away from the fault rupture are more vulnerable than those adjacent to the fault rupture by attracting more seismic demand. It is also verified that the shear keys are effective in restraining the bearing displacement on the near-fault span, particularly under the large permanent ground displacement.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.2
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• pp.134-141
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• 2022

This study presents a method for reducing current distortion that occurs when a dual-buck inverter generates reactive power. Dual-buck inverters, which are only capable of unity power factor operation, can generate reactive power capabilities by modifying a modulation technique. However, under non-unity power factor conditions, current distortion occurs at zero-crossing points of grid voltage and output current. This distortion is caused by parasitic capacitors, dead-time, and discontinuous conduction mode operation. This study proposes a modified modulation method to alleviate the current distortion at zero-crossing point of the grid voltage. A repetitive controller is applied to reduce this distortion of the output current. A 1 kVA prototype is built and tested. Simulation and experimental results demonstrate the effectiveness of the proposed method.

• Smart Structures and Systems
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• v.32 no.5
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• pp.339-347
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• 2023

Both the first author and the company of the second author were involved, directly or indirectly, in the design stage of a permanent link between the bottom of the Italian peninsula and the nearby Sicily island. This ambitious project was left in stand-by from 2013 to 2023. The current political revival originates some thoughts on the updated desired performance of suspension bridges, without any immediate reference to that specific crossing. It is simply regarded as a starting point. After an update on recent worldwide realizations, the authors focus their attention on four basic aspects: the span length, the girder scheme, the foundation technology and the bridge runability. Eventually, structural control and monitoring aspects are discussed as potentially innovative options in designing suspension bridges with railway crossing.

• Journal of Navigation and Port Research
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• v.48 no.2
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• pp.88-96
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• 2024

This study examined challenges posed by two ferry routes, namely, Likoni and Mtongwe crossings, in the Mombasa Channel and their impact on navigational safety. Utilizing the Environmental Stress (ES) model, this study analyzed current ship traffic and assessed stress levels imposed by ferry crossing traffic on navigators. ES values revealed significant stress at these ferry crossings attributed to varying transit speeds. Standardizing transit speeds at two ferry passages can reduce high stress levels, presenting a viable solution. Furthermore, the IWRAP Mk2 simulation underscores crossing collisions as a significant concern, particularly at Likoni and Mtongwe crossings, due to increased ferry traffic. This research offers valuable insights for stakeholders, such as the Kenya Ports Authority (KPA), to develop targeted safety measures and enhance the flow of ship traffic in the channel.

• Journal of Korean Society of Transportation
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• v.33 no.2
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• pp.136-144
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• 2015

It has reported that a median bus-stop island on an exclusive median bus corridor has shortened a unit crossing distance, encouraged a pedestrian's illegal jay walking, and thus increased the number of accidents in the area. Therefore, this study plans to analyze the various crossing patterns of pedestrians at exclusive median bus corridors. This study analyzes 30,184 pedestrian crossing data which are collected from the median bus-stops, 'Express Bus Terminal,' and reveals that the rate of spatial jaywalking was 37.8%. This rate is 11.1 times higher than the rate of traffic signal violation. Therefore, this study suggests that more research needs to be done to provide a traffic safety facilities for protecting spatial crossing pedestrians and preventing jaywalking and traffic signal violation.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.10
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• pp.1353-1358
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• 2000

The three-way rotational crossing experiment has been conducted to evaluate heterosis effects on jumping height and body weight. Yonakuni wild mice (Y) and two genetic groups of $CF_{{\sharp}1}$ (C) and C3H/HeNCrj (H) laboratory mice were used as materials. Reciprocal rotational crossing was made by crossing C male${\times}$Y female and Y male${\times}$C female to produce basic group designated $G_0$ and ${G_0}^{\prime}$, respectively. The females of the $G_0$ and ${G_0}^{\prime}$ were mated to the H sire to produce second generation ($G_1$ and ${G_1}^{\prime}$), and at the following generation the replacement females were mated to Y or C sire according to the basic group to produce $G_2$ to $G_3$ and ${G_2}^{\prime}$ to ${G_3}^{\prime}$. Individual jumping height data at Wk6 and body weight data at 1 (Wk1), 3 (Wk3), 6 (Wk6) and 10 (Wk10) weeks of age were analyzed. The results showed that effects of genetic group, sex and interaction of genetic group by sex were significant (p<0.01) for jumping height. For males, 55.34%~79.17% and 54.46%~78.29% of heterosis were reached at $G_1$ to $G_3$ and ${G_1}^{\prime}$ to ${G_3}^{\prime}$, respectively. While for females at $G_1$ to $G_3$ and at ${G_1}^{\prime}$ to ${G_3}^{\prime}$, heterosis effects were 61.53%~80.42% and 47.79%~85.86%, respectively. For body weight, genetic group was a significant source of variation at all ages studied. Sex effect was significant at Wk3, Wk6 and Wk10, and interaction between genetic group and sex was significant at Wk6 and Wk10 (p<0.01). C sires resulted in the highest body weight of offspring, while H sires were the intermediate and Y sires were the lightest. The significant positive and negative heterosis effects for body weight were exhibited. Crossing involved the Y sires in addition to smaller maternal effects of Y dams tended to result in small heterosis.

• Journal of Astronomy and Space Sciences
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• v.22 no.3
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• pp.249-262
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• 2005

Optimization problems are formulated to calculate optimal impulses for deflecting Earth-Crossing Objects using a Nonlinear Programming. This formulation allows us to analyze the velocity changes in normal direction to the celestial body's orbital plane, which is neglected in many previous studies. The constrained optimization in the three-dimensional space is based on a patched conic method including the Earth's gravitational effects, and yields impulsive ${\Delta}V$ to deflect the target's orbit. The optimal solution is dependent on relative positions and velocities between the Earth and the Earth-crossing objects, and can be represented by optimal magnitude and angle of ${\Delta}V $ as a functions of a impulse time. The perpendicular component of ${\Delta}V $ to the orbit plane can sometimes play un-negligible role as the impulse time approaches the impact time. The optimal ${\Delta}V $ is increased when the original orbit of Earth-crossing object is more similar to the Earth's orbit, and is also exponentially increased as the impulse time reaches to the impact time. The analyses performed in present paper can be used to the deflection missions in the future.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.3
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• pp.299-305
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• 2011

Purpose: In watching 3D stereoscopic display using the binocular disparity, effect of difference of the pupillary distance between the adults and children on the perception of depth were investigated. Methods: The average PD of children was determined from the PD measurements of children of the elementary school of 2nd and 3rd grade in Seoul. The location of crossing visual axes were derived from the relation of the binocular disparity and the PD for the adults and children. Results: The average PD of the children was measured to be 57.3 mm which was smaller than the average PD of the adults that was known to be about 65 mm. As the binocular disparity increases to the positive direction, the crossing location steeply moves farther behind the screen. On the other hand, when the binocular disparity increases to the negative direction, the crossing location gradually moves toward the viewer. For the same amount of the binocular disparity, the crossing locations were derived to be larger for the children than the adults due to the difference of the PD. Therefore, children will perceive larger depth than the adults. Conclusions: Small PD of the viewer causes the larger amount of the depth perception. In producing the stereoscopic images, the average PD of children as well as adults need to be considered.

• FLOWER RESEARCH JOURNAL
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• v.18 no.3
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• pp.193-200
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• 2010

Current rose cultivars are all composed of heterozygous genome due to long history of out crossing including interspecific hybridization. It has been adapted by artificial selection and crossing by breeders that mainly based on the crossing with fertile pollen derived from inter- or intra-specific hybridization. Pollen viability and germination ability tests provide valuable information for the designing of parentage for more successful breeding efficacy. In this study, we tested the pollen viability and germination ability in seven rose cultivars to find any relationship among several factors including pollen size, ploidy levels, and crossing compatibility. The pollen viability showed wide ranges from 39% 'Pinocchio' as minimum to 82% 'Scarlet Mimi' as maximum, whereas pollen germination rate were from 1% 'Mini Rosa' to 41% 'Scarlet Mimi' as a highest. Pollen size ranged from 41.3 to $45.4{\mu}m$ in large sized pollen and 30.7 to $37.4{\mu}m$ in small sized pollen. The mean diameter of large sized pollen is approximately 10-40% bigger than that of small sized pollen. There are positive relationships among ploidy level, total chromosome length, and pollen size. Crossing list showed that seed setting ratio and seed germination were related to pollen viability, pollen germination, and ploidy level.