• Journal of the Korean Society of Visualization
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• v.8 no.4
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• pp.38-42
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• 2010

Ion concentration polarization is an electrokinetic phenomenon which occurs in membrane systems, such as in an electrodialysis and fuel-cell system. But the phenomenon is not fully understood because hydrodynamics, electrokinetics and electrochemistry are coupled with each other. Here, we report that there occurs a change of pH value of buffer solution in concentration polarization phenomenon. To visualize the change of pH, the litmus solution which is one of the pH indicators was used. It is conjectured that the pH of solution changes because hydrogen ions were concentrated in cathodic side and hydroxide ions were concentrated in anodic side. We anticipate that this work may contribute to the fundamental understanding on the ion concentration polarization phenomenon.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.1
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• pp.94-97
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• 2015

In this study, we introduce a yellowing phenomenon in silver nanowire laser patterning and attempt to understand the cause of this phenomenon. Silver nanowire is a promising alternative to indium tin oxide as a transparent electrode owing to its flexibility. Additionally, silver nanowire can be easily patterned by laser ablation, which is free of dangerous chemicals. However, a yellowish color change reducing visibility is observed on the patterned area of the silver nanowires, and this yellowing phenomenon prevents the use of silver nanowire as a transparent electrode material. We concluded that resolidified debris of melted and evaporated silver nanowires after laser ablation causes the color change of the electrode. Further research is needed to determine a means of mitigating this yellowing phenomenon.

• International Journal of Fluid Machinery and Systems
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• v.7 no.2
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• pp.54-59
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• 2014

Particle Image Velocimetry combined with developed image processing method is adopted to study the liquid-solid two phase flow in the centrifugal pump impeller with crystallization phenomenon. The tracer particle is used to follow the liquid phase, which has the diameter between 8 to $12{\mu}m$. The crystal particle precipitates from the sodium sulfate solution does change the wavelength of the laser, and which has great laser scattering characteristics. The diameter of the crystal particle is larger than $20{\mu}m$. Through calculating the diameter of the particles in the image, the tracer particle and the crystal particle can be distinguished. By analyzing the experimental result, the following conclusion has been obtained. During the delay period, there is not any crystal particle and the pump performance has not been changed. As the crystallization process begins, the crystal nuclei appears from the supersaturation solution and grows larger with temperature decreasing, which has the tendency of moving towards the pressure side. The characteristics of liquid-solid two phase flow with crystallization phenomenon in the pump are obtained according to analysis of experimental results, and some guiding advices are presented to mitigate the crystallization phenomenon in pump impeller.

• The Research Journal of the Costume Culture
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• v.17 no.5
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• pp.733-745
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• 2009

The contra-sexual phenomenon that is recently focused is one of the new factors, which is focused when explaining the life style of progressive woman's image and it is creating cultural category. Moreover, the contra sexual people that are rising as new consuming subjects are not simple primary consumers but their shopping culture and cultural tastes are giving effects to many people. Because of the tendency, marketer of consuming industry are making efforts to predict the changes of contra-sexual people's shopping habits and tastes. Therefore, it is necessary to grasp contra-sexual phenomenon and research the fashion design aiming at that in order to predict woman's fashion image in the future. Therefore, the study considered concept and characteristic of contra-sexual phenomenon and surveyed its example in the popular culture. And, the study analyzed the formative characteristic of contra-sexual fashion shown in the public cultures such as drama and movie. On the basis of the result, design was suggested by reflecting contra-sexual fashion characteristic under the concept of 'Urban Splendor'. From the results above, it was possible to grasp the concept and characteristic of contra-sexual phenomenon, which appeared as a trend and understand new woman's image and the fashion that has changed because of it. It is considered that the establishment of the foundation of contra-sexual phenomenon, which plays as an important variable in woman's fashion, fashion accessory, cosmetic and advertisement field but it is hard to clarify, by analyzing the work aiming at contra-sexual phenomenon will be helpful for predicting the change of woman's fashion in the future.

• Journal of Fashion Business
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• v.14 no.5
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• pp.78-92
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• 2010

The culture phenomenon, which the desire of self expression is noticeable and the diversity of gender identity is widely accepted, simply makes a difference in the lifestyle of one human being rather than the dichotomous classification of male and female. Now, the delicate and aesthetic sensitivity classified as the feminine characteristics is no longer the exclusive property of female and this refers to substituting it as a social gender from the concept of biological sex. This phenomenon has influenced on the male culture and is creating various codes according to the cultural gender extended from the gender as a social role. Also, the transition into the western lifestyle has extended the aesthetic emotion to accommodate new codes from the diversification and globalization of lifestyle. The mansumer power, which does not care too much about the money for the emotionally attached items, has enabled various fashion styles. After analyzing the diversified clothing behavior conducted by these people in connection with the social phenomenon, First, this shows the phenomenon of emotional value pursuit that finds pleasure over the clothing as the item of augmented reality is added to the concept of play, in which the real space referred to as garment and virtual space of playing the rock, paper and scissors game meet together within the augmented reality. Second, the convergence concept has enabled the coordination of new style by obscuring the area of design concept and this refers to the changes in design from the development of new items and transformation into double-style details. Third, the divergence that intensively provides specific use/convenience and specialized value shows a change in the fashion market from the phenomenon that admits various gene rations of culture and specifically, takes differently about the recognition of middle-aged males. Fourth, the variety seeking tendency receives attention as the value of future design together with the phenomenon of discriminative value pursuit. In the male fashion, it is linked to the collaboration with the design area and this tells that the fashion with the narcissistic cross-dressing and motto of neutral gender without being sided to male/female is rising.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.6
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• pp.589-595
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• 2013

This paper was to study the effect to Yongrak phenomenon of I groove submerged arc welding depending on the plasma cutting surface characteristics, and how to reduce the causes and characteristics Yongrak phenomenon. Shipbuilding and marine structures is designed to use the thick plates and welded by high current to obtain deep penetration. Yongrak phenomenon has been occurred frequently depending on the quality of cutting surface and it makes degrade of the welding quality and modification of the welding. As a result, it was confirmed that I Groove plasma cutting characteristics get bevel form of 2 to 4 degrees to one side direction from the vertical position with Yongrak phenomenon. This is the main reason of Yongrak phenomenon in butt joint welding and 4 degree reverse bevel on the upper surface of base metal by submerged arc welding brought the effect of significant reduction of Yongrak phenomenon.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.994-999
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• 2011

The main wearing slider of pantograph is a difference which is considerable to wear phenomenon according to material properties. Especially, Cu-type wearing slider suddenly occurs the abnormal wear by precipitation, this threatens the travelling safety of the train. The abnormal wear by precipitation and arc influences are main factor decided to life time of Cu-type wearing slider and contact wire. Consequently, the application of the main wearing slider with wear resisting capacity, electrical conductivity, resistance arc and lubrication is demanded. In this paper through tribologic approach, overcame abnormal phenomenon of the Cu-type wearing slider by the precipitation and for the economic efficient augmentation by durability improvement and the travelling safety were accomplished. The Cu-type wearing slider which has excellent electric conductivity and arc characteristic but it occurs the normal and abnormal wear phenomenon according the precipitation which changes, respectively. Consequently, this phenomenon grasps fixed quantity according to precipitation, a mileage and wear volume then Fe-type wearing slider compared and analyzed.

• Journal of KSNVE
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• v.4 no.3
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• pp.353-363
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• 1994

The non-preiodic fluctuation of the engine torque appears to be the major source of the torsional vibration of the automotive driveline. The reduction of this torsional vibration hs become a significant problem along with the requirements of higher performance. The shuffle(tip-in, tip-out) is the transient vibration phenomenon of a vehicle which appears at the sudden change of an accelerator under traveling. By executing of an experiment and a simulation using a model, it has become possible to obtain the design parameter of a driveline for the torsional vibration. This paper presents an experimental and theoretical research on the transient vibration phenomenon of a vehicle which appears at the sudden change of an accelerator under traveling. A dynamic model for the automotive driveline was developed, and all parameters of the mmdel were evaluated with experimental data. The results are as follows: (1) The lower the gea ratio of the transmission is, the more the transient vibration phenomenon of a vehicle appears clearly. (2) The transient vibration phenomenon of a vehicle is affected by the design parmeter of the driveline.

• Bulletin of the Korean Mathematical Society
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• v.42 no.4
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• pp.855-867
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• 2005

Shattering or disintegration of mass is a well known phenomenon in fragmentation processes first introduced by Kol­mogorov and Filippop and extensively studied by many physicists. Though the mass is conserved in each break-up, the total mass decreases in finite time. We investigate this phenomenon in the n particle system. In this system, shattering can be interpreted such that, in uniformly bounded time on n, order n of mass is located in order o(n) of clusters. It turns out that the tagged particle processes associated with the systems are useful tools to analyze the phenomenon. For the newly defined stochastic shattering based on the above ideas, we derive far sharper conditions of fragmentation kernels which guarantee the occurrence of such a phenomenon than our previous work [9].

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.1
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• pp.1-6
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• 2016

Recently, proportion of the induction motor load is gradually increased. When a contingency in the power systems, it has been discovered phenomenon that the voltage is delayed recover caused mechanical characteristics of the induction motor load. It can be a serious impact on the voltage stability of the power system considering induction motor load. The scheme to mitigate this phenomenon tripping off the motors to prevent voltage drop and delayed voltage recovery on the load demand side. Fault induced delayed voltage recovery phenomenon is caused by stalling of small induction motor load in transmission level contingencies. In this paper, fault induced delayed voltage recovery phenomenon mitigation method implementation under voltage load shedding on the korean power system considering induction motor load.