• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.1053-1057
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• 1997

Laser thin film process with a Q-switch pulsed YAG laser was performed for micro machining. In this research, we performed basic Cr thin film on glass substrates removal machining experiments. Form experiments, it happens not only evaporration of thin film but also spatter and cohesion of melting substance in working region, when machining a Cr thin film by Q-switch YAG laser beam irradiation. Critical energy of surface irradiation type by irradiation direction of laser in a face composing thin film on the glass is higher than that of back irradiation type, but the latter is favorable because of spatter appearance. In case of image formation position when laser beam is irradiated, the defocus is permitted to a certain extent within forcus depth. Ifexceeds focus depth, formation of pattern is vanishing step by step.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.469-473
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• 2006

Film-forming yeasts generate an undesirable yeasty flavor in fermented vegetables such as kimchi in the presence of oxygen. Antimicrobial materials including garlic oil (GO), heated garlic (HG), and allyl alcohol (AA) were investigated for use as alternative natural food preservatives to inhibit the growth of film-forming yeasts in fermented vegetables. Using the fermentation of cucumber pickles as a model system, GO, HG, and AA were effective in preventing film formation at concentrations of 0.006, 3.0, and 0.02%, respectively. The effectiveness of HG in preventing the growth of a film yeast, Hansenula anomala, was not influenced by pH, while that of potassium sorbate, a typical anti-yeast food preservative, was highly dependent on pH. All tested materials were effective when added at the beginning of fermentation due to their negligible inhibitory activity toward lactic acid bacteria.

• Applied Science and Convergence Technology
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• v.27 no.5
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• pp.105-108
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• 2018

Transparent $TiO_2$ nanotube arrays are successfully prepared by a two-step approach involving electrochemical anodization and RF magnetron sputtering. First, a Ti film is deposited on an FTO substrate by RF magnetron sputtering at room temperature. The morphologies of the Ti film are controlled by the working distance, Ar flow, and DC power. Second, an anodization treatment is electrochemically performed for the formation of nanotube arrays from the deposited Ti film, followed by post-annealing treatment in air for the formation of $TiO_2$ crystallization. The back side of the crystallized $TiO_2$ nanotube arrays is illuminated with solar light to characterize the photoelectrochemical reaction, and their photoelectrochemical properties are investigated. This work provides information on application of a thin film deposited by RF sputtering in the field of photoelectrochemical water splitting.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.87-89
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• 1994

The effects of low molecular weight components of LDPE and sample molding condition were investigated to find the orgins for heterocharge in LDPE without any addtives. Low molecular weight chains of LDPE encourages the formation of heterocharge by being charged and migrating the counter electrode. The formation of heteroohage in LDPE was also effected by sample preparation process and the kind of a moling film. When PET film is used as a molding layer, the carbonyl, which may lead to increase the heterocharge, formed at surface of LDPE.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.125-139
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• 2014

In this study, we're going to look at the formation process of Youth film Festival and factors affecting that process. The Youth film Festival didn't appear suddenly in a day. There have been various trial regarding media education by civil society organizations (NGO) until the mid 1990s, principal Youth film Festival has been held from 1997s to 2001s and established a framework for Youth film Festival. There were some progress after those times and then in 2008 Youth film Festival faced some changes such as screening online, and responded rapidly to the current image industry and the cultural stream like the appearance of HD camcoder and smart phone till now. We can divide two areas regarding factors that affecting those formation process of Youth film Festival. First, they are explained as economic and social factors that the situation of South Korea extremely such as the efforts of civil society organizations (NGO), image technology and development of the industry, IMF bailout era and so on, second cultural and educational factors that the rise of virtual culture, the University entrance and results of awards. Thus Youth film Festival has been evolved in various affects, so we can look into the various sections of korea society through these formation process of Youth film Festival.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.35-38
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• 1995

Indium Tin Oxide(ITO) thin film is transparent to visible ray and conductive in electricity. It is seen that the samples made by the sputtering process have high transmission rate to visible ray and high adhesion , but the planar type magnetron sputtering process with is very well known in industrial region have a defect of partial erosion on the surface of target and a high loss of target and also since the substrate is positioned in plasma, the damage on thin film surface is caused by the reaction with plasma. In cylindrical magnetron sputtering system. it is known that the loss of target is little , the damage of thin film is very little and the adhesion of thin film with substrate is strong. In this study, we have made ITO thin film in the cylindrical DC magnetron system with the variable of substrate temperature , magnetic field, vacuum condution and the applied voltage. The general temperature for formation on ITO is asked at 350 $^{\circ}C$~400$^{\circ}C$ but we have made ITO is low temperature(80-150$^{\circ}C$) By studing electrical and optical properties of ITO thin fims made by varing several condition, we have searched the optimal condition for formation in the best ITO in low temperature.

• Journal of the Korean Electrochemical Society
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• v.13 no.1
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• pp.19-33
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• 2010

The surface film, which is formed on graphite negative electrodes during the initial charging, is a key component in lithium secondary batteries. The battery reactions are strongly affected by the nature of the surface film. It is thus very important to understand the physicochemical properties of the surface film. On the other hand, the surface film formation is a very complicated interfacial phenomenon occurring at the graphite/electrolyte interface. In studies on electrode surfaces in lithium secondary batteries, in-situ experimental techniques are very important because the surface film is highly reactive and unstable in the air. In this respect electrochemical atomic force microscopy (ECAFM) is a useful tool for direct visualizing electrode/solution interfaces at which various electrochemical reactions occur under potential control. In the present review, mechanism of surface film formation and its correlation with electrolyte are summarized on the basis of in-situ ECAFM studies for understanding of the nature of the surface film on graphite negative electrodes.

• Korean Journal of Materials Research
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• v.4 no.7
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• pp.750-758
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• 1994

The purpose of present study is to find out the formation mechanism of hemi-spherical grained(HSG) polysilicon film. Silicon film was deposited using LPCVD. Polycrystalline silicon film was deposited at $575^{\circ}C$ contained crystalline HSG in the amorphous matrix phase. The crystalline HSG can be categorized into two grains : lower grains and upper grains. Lower grains are located at interface between silicon dioxide and silicon film, and upper grains are located at surface. The growth orientations of HSG were identified as (311) or (111) directions for lower grains and perferentially (110) direction for upper grains. This difference of growth orientations seems to be caused by the difference of formation mechanisms. That is, lower grain is formed by soild phase crystallization, on the other hand, upper grain is formed by surface diffusion of silicon atoms. It was thus, proposed that the formation of practical HSG polysilicon film is mainly controlled by surface diffusion of silicon atoms.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.05a
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• pp.226-234
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• 2002

A systematic study of the role of transfer films on friction properties was performed with various temperatures in the brake system. An NAO friction material specimens containing 9 ingredients were tested using a pad-on-disk type friction tester A new method of measuring the transfer film thickness was developed by considering the electrical resistance of the transfer film using a 4-point probe technique. The properties of transfer film such as surface morphology and film distribution vaied according to the relative amount of graphite and magnesium oxide. By using SEM, it was possible to obtain information about the chemical composition of the transfer film. Results showed that there detected a threshold value of the relative amount of a two active materials to maintain a certiain thickness of a transfer film. Results also showed that formation of friction layer generated on the friction surface was strongly affected by chemical action of two ingredients during sliding due to chemical reaction of solid lubricants at different interface temperature. The results suggested that no apparent relationship between transfer film thickness and the average friction coefficient was founded and friction characteristics were affected more by the property of the solid lubricant and abrasive in the material.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.554-557
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• 2011

One of the issues that occurs in development of a combustor using Metal Powder as a fuel is an alumina slag processing. A water film formed inside the combustor is expected to be able to solve this issue. The experiments about the formation of a water film were carried out as a preliminary study. As the tangential velocity of water jet is increasing, the angle derivation from horizontal is decreasing for the test model. Results of the experiments showed that the thin water film on the inner surface appeared at the velocity of 10~15 m/s.