• Journal of the Korean institute of surface engineering
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• v.15 no.1
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• pp.24-38
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• 1982

The Objective of this study is to analyze structural and operational aspects of the govern-ment, its associations, industries and academic associations related to metal-plating industry, and thereby recommend ways of promotion of subsector, which is yet to be developed. Stages for the implementation are proposed as follows. 1) Stage One: Preparation for formation of proper atmosphere. ⅰ) Clearance of unlicenced metal-plating factories. ⅱ) Strengthening of functions of the association. ⅲ) Provision of incentives through the tax system. 2) Stage-Two : Modernization and maturity ⅰ) Introduction of system for indicating quality of products. ⅱ) Implementation of joint and cooperative-based programs ⅲ) Technical advancement of the closed system and anti-pollution treatment. 3) Stage Three : Settlement ⅰ) Systematic use of statistics and information. ⅱ) Standardization of quality of the products.

• Corrosion Science and Technology
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• v.6 no.5
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• pp.245-250
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• 2007

Recently, to avoid global warming, reduction of $CO_2$ generation has been demanded. Each car manufacture takes positive actions for improvement in fuel consumption by various kinds of countermeasures, e.g. improving engine efficiency, using alternative fuels, lightening the car body. Regarding lightening of the car body, aluminum alloys and high tensile strength steels has been gradually adopted as lightweight materials. However, such materials are normally not easy to be treated with zinc phosphate system. Focusing the pre-treatment processes, low temperature phosphate system could be demanded for energy saving. This time, new surface conditioning process for lightweight materials and low temperature phosphate system shall be discussed.

• Journal of the Korean institute of surface engineering
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• v.32 no.3
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• pp.303-306
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• 1999

On the effect of substrate bias at first stage of diamond synthesis at lower substrate temperature(approximately 673K) using microwave plasma CVD and effect of reaction gas system for the bias enhanced nucleation were studied. The reaction gas was mixture of methane and hydrogen or carbon monoxide and hydrogen. The nucleation density of applied bias -150V using $CH_4-H_2$ reaction gas system, significantly higher than that of $C-H_2$ reaction gas system. When the $CH_4-H_2$ reaction was used, nucleation density was increased because of existence of SiC as a interface for diamond nucleation. By use of this negative bias effect for fabrication of CVD diamond film using two-step diamond growth without pre-treatment, fabrication of the diamond film consist of diamond grains $0.2\mu\textrm{m}$ in diameter was demonstrated

• Korean Journal of Digital Imaging in Medicine
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• v.11 no.2
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• pp.101-107
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• 2009

With the recent development of diagnosis using radiation and increasing demand of the medical treatment, we need to minimize radiation exposure dose. So, This is the method which reduce patient dose by measuring surface dose of radiographic change factor and by comparing theoretical and actual dose, when we take an X-ray which is generally used. By changing the factor of kV, mAs, FSD, whose range is 60 to 120 kV, 20 to 100 mAs, 80 to 180 cm, we compared theoretical surface dose with actual surface dose calculated by the simple calculation program, Bit system, and NDD-M method As a result, when kV and mAs were higher, theoretical surface dose and actual surface dose were more increased. but the higher FSD was, the more decreased surface dose was. According to this, the error were measured about 0.1 to 0.2 mGy in low dose part and about 0.7 to 1.5 mGy in high dose part. Therefore, this shows that theoretical surface dose calculation method is more correct in low dose part than in high dose part. In conclusion, we will have to make constant efforts which can reduce patient and radiographer's exposure dose, studying methods which can predict patient's radiation exposure dose more exactly.

• Biomedical Science Letters
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• v.14 no.2
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• pp.105-113
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• 2008

The objective of this study was to evaluate the influence of surface modifications on the bonding characteristics and cytotoxicity of specific titanium porcelain bonded to milling titanium and cast titanium. Milling titanium and cast titanium samples were divided into 8 test groups. These groups are as follow: i) sandblasted with particles of different size of $220{\mu}m\;and\;50{\mu}m$, ii) different sequences of sandblasting treatment and etching treatment, iii) etched with different etching solutions, and iv) preheated or not. The surface characteristics of specimens were characterized by the test of mean roughness of surface and SEM. The bond strength of titanium-ceramic systems was measured by using three-point bending test and SEM. The results show that the mean roughness of surface of sample sandblasted with $220{\mu}m$ aluminum oxide increased and bond strength were higher than sample sandblasted with $50{\mu}m$ aluminum oxide. The mean roughness of surface decreased, but the bond strength increased when the samples sandblasted with $220{\mu}m$ aluminum oxide were preheated. The sample sandblasted with $220{\mu}m$ aluminum oxide after oxidized with occupational corrosive agent I (50% NaOH, 10% $CuSO_4{\cdot}5H_2O$) and II (35% $HNO_3$, 5% HF) showed higher bond strength than sample oxidized with 30% $HNO_3$ after sandblasted with $220{\mu}m$ aluminum oxide. Group NaCuNF220SP (milling Ti: 35.3985 MPa, casting Ti: 37.2306 MPa) which was treated with occupational corrosive agent I (50% NaOH, 10% $CuSO_4{\cdot}5H_2O$) and II (35% $HNO_3$, 5% HF), followed by sandblasting with $220{\mu}m$ aluminum oxide and preheating at $750^{\circ}C$ for 1 hour showed the highest bond strength and significant differences (P<0.05). The method for modifying surface of titanium showed excellent stability of cells.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.121-124
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• 2001

Surface-modified silica holds considerable promise in the development of advanced materials for good mechanical properties and stability. In this work, the surface and mechanical interfacial properties of silicas treated with silane coupling agents, such as Y-methacryloxy propyl trimethoxy silane (MPS). Y-glycidoxy propyl trimethoxy silane (GPS), and Y-mercapto propyl trimethoxy silane (MCPS), are investigated. The effect of silane surface treatments of silica on the surface properties and surface energetics are studied in terms of surface functional values and contact angle measurements. And their mechanical interfacial properties of the silica/rubber composites are studied by the composite tearing energy ($G_{IIIC}$). As a result. the mechanical interfacial properties are improved in the case of silane-treated composites compared with untreated one. It reveals that the functional groups on silica surface by silane surface treatments play an important role in improving the degree of adhesion at interfaces in a silica-filled rubber system.

• Journal of Environmental Science International
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• v.15 no.9
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• pp.871-880
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• 2006

Water management treatment of coastal region has been an important problem in Jeju city since the distributions of pipeline of the pumping system made a bad view in coastal region. To solve the problem, we observed the pipelines that are on the surface around the coastal region from Tapdong to Doduhang. From the observations, we found that Todong and Dodu areas were not unsightliness because the all pipelines were located in underground. However, the other areas, such area Yongdam, Handugi, Yongdam fishing village, had a serious problem for the coastal landscape view. To solve the problem, at we estimated coastal land color characteristics of Jeju city based on the observation of the pipelines. The estimated color panel shows that the green, blue and grey colors are a dominant factors of the Jeju coastal region. Based on the color panel, we proposed two methods, that is, one is a short time treatment, the other is a long time one. The short is based on the colour treatment, which is pipeline colour changing into surround natural one. The long time is the construction plan design method. Although the later method was very useful in Jeju island. However, it takes a lot of time and money. Therefore, in the situation, the short time is the better than the long time one.

• Journal of the Korean Vacuum Society
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• v.19 no.1
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• pp.22-27
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• 2010

To improve surface wettability, each sample was treated by atmospheric pressure plasma (APP) using dielectric barrier discharge (DBD) system. Argon and oxygen gases were used for treatment gas to modify the $TiO_2$ surface by APP with RF power range from 50 to 200 W. Water contact angle was decreased from $20^{\circ}$ to $10^{\circ}$ with argon only. However, water contact angle was decreased from $20^{\circ}$ to < $1^{\circ}$ with mixture of argon and oxygen. Water contact angle with $O_2$ plasma was lower than water contact angle with Ar plasma at the same RF power. It seems to be increasing the polar force of $TiO_2$ surface. Also, analysis result of X-ray photoelectron spectra (XPS) shows the increase of intensity of O1s shoulder peak, resulting in increasing of surface wettability by APP. Moreover, each water contact angle increased according to increase past time. However, contact angle increase with plasma treatment was lower than without plasma treatment. Additionally, the efficiency of $TiO_2$ photocatalyst was improved by plasma surface-treatment through the degradation experiment of phenol.

• Journal of the Korean Ceramic Society
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• v.30 no.9
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• pp.775-783
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• 1993

TiO2-SiO2 system anti-reflective(AR) film was prepared to decrease reflectance on the glass surface. The experiments were carried out as fellow, 1) preparation & hydrolysis of TiO2-SiO2 system sols. 2) glass dipping, and 3) drying & heat treatment. We investigated the refractive index and thickness of film with viscosity, zeta-potential of sol, sol concentration, withdrawal speed, drying and heat treatment condition. As a result, we prepared good qualitative Quarter-Half-Quarter type anti-reflective film that had minimum, 0.02% and average reflectance, 0.087% in the visible region.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.1
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• pp.13-17
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• 2017

The sectors of the Root industry include casting, plastic works, welding, surface treatment, and heat treatment. While the industry is concerned with the processing technologies that are used in most of the manufacturing industries, the sophistication of the corresponding manufacturing information systems is very low. This paper describes a manufacturing information system for the building sector for which the smartphone devices that the workers use in their daily lives are employed, and where the cost of the adaption of the manufacturing system at their factories is minimized. The proposed system consists of the following three parts: UI composer, General Application, and Gateway.