• Journal of Surface Science and Engineering
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• v.33 no.5
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• pp.387-397
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• 2000

Antimony in the galvanizing bath had greater effect on the growth of grains in the solidification of molten coating layer and on the decrease of its surface roughness than lead. Particularly 0.01 wt % antimony in the galvanizing bath showed much stronger effect than expected considering its low surface tension value. These effects were seemingly originated from the development of preferred orientation of (0002) plane parallel to steel surface. Antimony was found to be widely distributed in form of orderly arrangement throughout the coating layer unlike lead from the results of surface analyses on coating layers as received and on those as etched in chromating solution. In addition, supercooling in the 0.07 % antimony and the 0.2 % lead galvanizing bath was also measured to be in the range of$ 2~4^{\circ}C$ and $9~11^{\circ}C$ respectively, and it indicates that antimony forms fine dendrite expanded rapidly on the steel surface.

• Journal of Power Electronics
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• v.19 no.5
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• pp.1122-1132
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• 2019

In this paper, aiming at high-voltage applications, transformer windings schemes of multiple-output two-transistor flyback converters are investigated, which are mainly based on the stray capacitances effect. First, based on a transformer model including equivalent stray capacitors, the operational principle of the converter is presented, and the main influence of its stay capacitors is determined. Second, the windings structures of the transformer are analyzed and designed based on the stray capacitances effect. Third, the windings arrangements of the transformer are analyzed and designed through a coupling analysis of the secondary windings and a stray capacitance analysis between the primary and secondary windings. Finally, the analysis and design conclusions are verified by experimental results obtained from a 60W laboratory prototype of a multiple-output two-transistor flyback converter.

• Wind and Structures
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• v.27 no.6
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• pp.439-449
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• 2018

Wind loading of a tall building built amidst a group of buildings in urban environment is always greatly affected by shielding effects. Wind tunnel tests were carried out to assess the shielding provided by a row of low-rise or medium-rise buildings upstream a square-section tall building of height-to-breadth ratio 6. Mean and dynamic wind loads on the tall building were measured at different wind incidence angles and presented as interference factors (IFs). It is found that presence of a row of upstream buildings provides significant shielding to the tall building. At normal wind incidence, the mean along-wind loads and all components of fluctuating wind loads on the tall building are always reduced by shielding. Vortex shedding seems to still occur on the upper exposed part of the tall building but the vortex excitation levels are largely reduced. The degree of shielding is found to depend on a number of arrangement parameters of the row of upstream buildings. Empirical equations are proposed to quantify the shielding effect based on the wind tunnel data.

• International Journal of Computer Science & Network Security
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• v.21 no.6
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• pp.54-60
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• 2021

Monte-Carlo GO is a computer GO program that is sufficiently competent without using knowledge expressions of IGO. Although it is computationally intensive, the computational complexity can be reduced by properly pruning the IGO game tree. Here, I achieve this by using a potential model based on the knowledge expressions of IGO. The potential model treats GO stones as potentials. A specific potential distribution on the GO board results from a unique arrangement of stones on the board. Pruning using the potential model categorizes legal moves into effective and ineffective moves in accordance with the potential threshold. Here, certain pruning strategies based on potentials and potential gradients are experimentally evaluated. For different-sized boards, including an official-sized board, the effects of pruning strategies are evaluated in terms of their robustness. I successfully demonstrate pruning using a potential model to reduce the computational complexity of GO as well as the robustness of this effect across different-sized boards.

• Journal of Institute of Convergence Technology
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• v.11 no.1
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• pp.7-12
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• 2021

The magnetic gear, which amplifies the torque by filtering the magnetic field generated by the low-speed permanent magnet with a modulator, can exclude gear contact and can be effectively applied when there are environmental restrictions. In this paper, we discuss the magnetic force characteristics of a magnetic gear using a magnetic focusing array that replaces a general permanent magnet array magnetized in a radial direction along the circumferential direction. The torque increasing effect of the discussed array, known as an arrangement that increases the principal component by focusing a radial magnetic field, is compared with that of a general magnetic gear. In particular, in a magnetic gear using such an array, the sensitivity of torque according to variables is analyzed to see how various variables known as factors affecting torque have an effect.

• Earthquakes and Structures
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• v.21 no.6
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• pp.653-667
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• 2021

In this study, cyclic loading tests were conducted on the precast concrete (PC) wide beam (WB)-column joints. Two beam-column joint specimens were fabricated with the arrangement and anchorage details of the reinforcing bars penetrating the beam and column as variables. Through a cyclic loading test, the lateral load-story drift ratio responses, seismic performance characteristics (e.g., ductility, overstrength factor), energy dissipation, strength and stiffness degradations of each specimen were compared and analyzed based on the various indices and the current structural codes (ACI 318-19 and ACI 374.1-05 report). In addition, the shear lag effect was confirmed through the gauge values of the PC beam, and the differences in seismic performance between the specimens were identified on that basis.

• Transactions on Electrical and Electronic Materials
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• v.15 no.2
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• pp.77-80
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• 2014

The effect of reactive diluents on the ac electrical treeing in epoxy/nanosilicate systems was studied, in a needle-plate electrode geometry. Diglycidyl ether of bisphenol A (DGEBA) type epoxy was used as a base resin, and layered silicate was used as a nano-sized filler. Polyglycol (PG) or 1,4-butanediol diglycidyl ether (BDGE) was introduced as a reactive diluent to the DGEBA/nanosilicate system, in order to decrease the viscosity of the nanocomposite system. PG acted as a flexibilizer, and BDGE acted as a chain extender, after the curing reaction. To measure the treeing propagation rate, a constant alternating current (ac) of 10 kV/4.2 mm (60 Hz) was applied to the specimen, in a needle-plate electrode arrangement, at $30^{\circ}C$ of insulating oil bath. When 10 kV/4.2 mm (60 Hz) was applied, the treeing propagate rate in the DGEBA system was $1.10{\times}10^{-3}$ mm/min, and that in the DGEBA/PG system was $1.05{\times}10^{-3}$ mm/min. As 1.5 wt% of nanosilicate was added to the DGEGA/PG system, the propagation rate was $0.33{\times}10^{-3}$ mm/min. This meant that the nano-sized layered silicates would act as good barriers to treeing propagation. The effect of chlorine content was also studied, and it was found that chlorine had a bad effect on the electrical insulation property of the epoxy system.

• Korean Institute of Interior Design Journal
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• no.3
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• pp.91-99
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• 1994

The purpose of this study was to determine the long term effect of a pleasantly designed interior on pro-saptial behavior. For pleasantly designed interior, the existing interior was remodeled through the change of finishing materials for major architectural elements such as wall, floor and ceiling, and changes of furniture and it's arrangement . Pro-spatial behavior was operationalized as seat arranging behavior and measured through the arranged condition and observable arranging behavior. Time-series design, one of quasi-experimental design was used. The data in this study were extracted from an existing field experimental research. Five hundred survey video tapes record during 2 years period were used. In conclusion, the pleasantly designed environment has a long term effect on the pro-spatial behavior change . While self-centered pro-spatial was improved continuously and even reinforced , altruistic pro-spatial behavior was improved but diminished as time passed. There were no differences in the effect between male and female children. The result of the research provide scientific background of an answer to why Interior Design.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1238-1242
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• 1998

Myocardial bridges as an anatomical arrangement in which an epicardial coronary artery becomes engulfed, for a limited segment, by myocardial fibers. These diseases are recognized primarily because of their systolic narrowing or milking effect as seen on coronary angiography. The most frequent site of myocardial bridging is the middle segment of left anterior descending artery. Myocardial bridges have an ischemic effect capable of causing : angina pectoris, myocardial infarction, ventricular fibrillation, or even sudden death in athletes. We report 2 patients having a milking effect of the middle segment of left anterior descending artery who were suffered from angina. The operation procedure was a simple supraarterial myotomy over the embedded segment of the LAD under cardiopulmonary bypass. Angina and milking effect were disappeared after the operation.

• Journal of the Korean Geosynthetics Society
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• v.10 no.4
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• pp.19-28
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• 2011

This paper presents the results of an investigation into the effect of cyclic wetting-drying on the compressive strength characteristics of decomposed granite soils. A series of plane strain compression (PSC) tests were performed on test specimens with varying fine contents under different wetting-drying cycles to investigate the change in compressive strength under the process of wetting-drying cycles. The effect of wetting-drying cycles on the structural particle rearrangement at a micro-scale level was also examined using scanning electron microscope (SEM) tests. It was shown that the soil containing larger fines showed more significant decrease in compressive strength compared with the soils with less fines. Also found was that the wetting-drying cycle did not have significant effect on the particle arrangement.