• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1550-1552
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• 1994

In order to investigate the effect of electrolyte solutions on the activities of bow-tie water trees in XLPE insulated power cable, we have tried to observe the characteristics on water treeing ( bow-tie type ) using several electrolyte solutions such as $CH_3COOH$, $MgCl_2$,HCl and NaCl solution and tap water. Bow-tie tree density in $CH_3COOH$ and $MgCl_2$ solution was higher than in any other solution, and the growth of tree was stimulated in NaCl and $CH_3COOH$ solution, and diffusion of bow-tie trees into insulation in $MgCl_2$, HCl and NaCl solutions was faster than in $CH_3COOH$ solution and water. Also, although the increase of applied voltage caused bow-tie tree density to be high, it didn't affect the growth of tree maximum length noticeably.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.23 no.1
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• pp.4-15
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• 2014

A face-bow and an articulator have been used as crucial devices in a prosthodontic reconstruction of a collapsed occlusal plane. In order to avoid inaccuracy of median line in maxilla and the canted occlusal plane both of which may result from using a facebow with ear rods, a facebow that locate a patient's facial median line as reference line has been under development. A mounting technique that tries to bring a center of patient's face into line with the center of the articulator, called esthetic mounting, is currently employed to overcome the imprecision resulted from mounting with ear-bow transfer. We would like to study a case that used OP finder 1, one of the esthetic mounting techniques.

• Nuclear Engineering and Technology
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• v.50 no.2
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• pp.297-305
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• 2018

Fuel assembly (FA) bow in pressurized water reactor (PWR) cores is considered to be a complex process with a large number of influencing mechanisms and several unknowns. Uncertainty and sensitivity analyses are a common way to assess the predictability of such complex phenomena. To perform such analyses, a structural model of a row of 15 FAs in the reactor core is implemented with the finite-element code ANSYS Mechanical APDL. The distribution of lateral hydraulic forces within the core row is estimated based on a two-dimensional Computational Fluid Dynamics model with porous media, assuming symmetric or asymmetric core inlet and outlet flow profiles. The influence of the creep rate on the bow amplitude is tested based on different creep models for guide tubes and fuel rods. Different FA initial states are considered: fresh FAs or FAs with higher burnup, which may be initially straight or exhibit an initial bow from previous cycles. The simulation results over one reactor cycle demonstrate that changes in the creep rate and the hydraulic conditions may have a considerable impact on the bow amplitudes and the bow patterns. A good knowledge of the specific creep behavior and the hydraulic conditions is therefore crucial for making reliable predictions.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.5
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• pp.91-100
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• 2008

A technique strengthened to the reinforced concrete members using the external post- tensioned method offers the advantages in speed and simplicity of installation over other, established, strengthening techniques. But this technique has many unreasonable facts. This paper are analyzed an unreasonable facts of the previous external post-tension technique. The purpose of this paper proposed Bow system as the new technique strengthened to the reinforced concrete members. The Bow system which is better technique than the previous technique was introduced with the experimental/analytical data.

• Bulletin of the Society of Naval Architects of Korea
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• v.5 no.2
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• pp.27-33
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• 1968

The resistance decreasing effects of a bulbous bow have been investigated with the model test results of the Korean standard type 10,000GT cargo vessel equipped with several different sized bulbous bows. The best bulbous bow for the design is 3.66% bulb which decrease the residual resitance 5%. The new hull combined with a bulbous bow have to be designed in other to get more effects.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.259-259
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• 2017

• Journal of the Korean Solar Energy Society
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• v.32 no.spc3
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• pp.194-198
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• 2012

Crystalline silicon solar cell remains the major player in the photovoltaic marketplace with 80% of the market, despite the development of various thin film technologies. Silicon's excellent efficiency, stability, material abundance and low toxicity have helped to maintain its position of dominance. However, the cost of silicon materials remains a major barrier to reducing the cost of silicon photovoltaics. Using the crystalline silicon wafer with thinner thickness is the promising way for cost and material reduction in the solar cell production. However, the thinner the silicon wafer is, the worse bow phenomenon is induced. The bow phenomenon is observed when two or more layers of materials with different temperature expansion coefficiencies are in contact, in this case silicon and aluminum. In this paper, the solar cells were fabricated with different thicknesses of Al layer in order to reduce the bow phenomenon. With less amount of paste applications, we observed that the bow could be reduced by up to 40% of the largest value with 120 micron thickness of the wafer even though the conversion efficiency decrease by 0.5% occurred. Since the bowed wafers lead to unacceptable yield losses during the module construction, the reduction of bow is indispensable on thin crystalline silicon solar cell. In this work, we have studied on the counterbalance between the bow and conversion efficiency and also suggest the formation of enough back surface field (BSF) with thinner Al layer application.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.1
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• pp.66-70
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• 2005

Cupid's bow, upper lip, columella, and ala of nose are esthetically important, in which their symmetrical plasties determine success or failure of the surgery in cleft lip and palate patients. Z-palsty and its modifications are simple and effective. The double Z-plasty is economical in surgical time and esthetics in reconstructing the cupid's bow compared with other methods. We report a 29-year-old male patient who represented reversed cupid's bow and whistle deformity after the primary repair of the cleft lip. He was corrected the cupid's bow using a double Z-plasty. The reversed cupid's bow was corrected to a normal shape and the whistle deformity disappeared. The tightness of the upper lip was relieved after the operation. The double Z-plasty was esthetically successful because the procedure was limited in the vermilion and did not produce a new scar on the skin. Furthermore, the lip tubercle became protuberant. The cupid's bow was symmetrically smoothly curved at 4 years after the operation. These results indicate that the double Z-plasty is simple, less traumatic to the surrounding tissues, and suitable for the correction of whistle deformity.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.923-929
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• 2018

In this study, we analyzed the resistance performance and running attitude of a catamaran by numerical analysis with a conventional bow, which is generally applied, and a reverse, protruding bow. The shape of the reverse bow was compared through numerical analysis and model tests. The reverse bow shape showed an improved wave pattern by shifting the generation position of the forward divergent wave to the aft in comparison with a conventional bow shape. This effect was found to be effective in determining resistance and stable running attitude. The hull resistance improved by about 2.95 %. The comparative numerical analysis and model test for the reverse bow shape completed in this study should be useful for future hull design application.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.4
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• pp.343-351
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• 2019

Green water impact may sometimes cause some structure damages on ship's bow deck. Prediction of proper design pressure against the green water impact is an essential task to prevent the possible damages on bow deck. This paper presents a computational method of the bow deck's design pressure against the green water impact. Large heave and pitch motions of ship are calculated by the time domain nonlinear strip method. Green water flow and pressure on bow deck are simulated by the predictor-corrector second kind upstream finite difference method. This green water simulation method is based on the shallow water wave equations expanded for moving bottom conditions. For various kind of ships such as container ship, VLCC, oil tanker and bulk carrier, the green water design pressures on bow deck are computed and discussed. Also, the obtained results of design pressure on bow deck are compared with those of the classification society rules and discussed.