• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.223-226
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• 2005

In this study on the appliable Asphalt sheet of monolithic and inorganic matter waterproofing ,Fing material using of field because of problem of complex waterproofing sheet. Before this cement polymer modified waterproof coating and appliable asphalt sheet of monolithic whether have stability by method of construction about all style waterproofing that evaluate to new method of construction development naturally big emphasis put and try to approach. Did performance test item first at, as a result, drew by suitable thing in all KS items. This is considered to have more effective spot construction work because if means that have stability by material as well as method of construction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.10
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• pp.1005-1013
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• 2009

In this paper, the performance improvement of a decentralized brake system for railway rolling stocks is investigated. In order to verify the effectiveness of the decentralized brake system, it is compared to the truck unit brake system which has only one control unit per a truck. The adaptive sliding mode control scheme is used to realize a robust anti-slip brake control system. Through computer simulations, it is verified that the decentralized brake system has better braking performance than the truck unit brake system.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.343-346
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• 2005

This study makes the performance evaluation of water-jet chipping through analysis of ruggedness of chipping surface. The ruggedness is mapped by 3D Laser Scanner and the results are also compared with the chipping surface by mechanical chipping. And the details of in-situ works is investigated for increasing interface adhesion between existing concrete and repairing mortar. Water-jet has good operation efficiency which is up $60m^2$ per hour when the chipping depth is 7cm and also has a large ruggedness about 1.65.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.517-520
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• 2006

The waterproofing of Building on the roof has been exposed more underground or the other part of waterproofing than environmental factor(solar heat, UV, salt, acid rain, wind, temperature, snow, rain, etc.) or physical factor. So it must be have a waterproofing performance and it has a special technique for the maintaining of concrete durability. Therefore, exposed waterproof layer has to protected from UV, solar heat, rain and the outside environment also, to endurance durability methods spread face plate topcoat material on the waterproof layer. But, actuality faceplate waterproof layer of topcoat materials are unbearable to UV, solar heat and moisture etc. and it doesn't have adhesion with waterproof layer in the middle. So it happens to crack, separating and heaving etc. Therefore, in the study, we will suggest that using of the exposed roof waterproof layer topcoat materials test method manage rooftop waterproof layer for the durability and the stability.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.04a
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• pp.1-19
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• 2003

The electronic market thrust for many hybrid circuit manufacturers is changing because commercial market segments such as telecommunications, automotive and consumer electronics have increased the demand world wide for environmentally friendly thick film products. This, in turn, places a stronger emphasis on the material suppliers within the circuit fabrication industry to provide toxin free products with equal or higher performance than traditional technology. A new group of silver based thick film conductors, which are totally free of such toxins as cadmium, nickel and Bead have been developed to meet new environmental requirements. Traditional thick film products and newly developed toxin free compositions will be compared and data will be presented. To evaluate their performance, both groups of conductors were tested for solder acceptance, leach resistance and aged adhesion with standard lead-containing solder and higher temperature lead-free solder.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.3
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• pp.71-78
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• 2010

The end shape of tube for automobile power steering system has influence on the ability of performance. In this case study, we attempted to optimize the forming process of a small tube using Taguchi experimental design methodology. A preliminary experiment was conducted and four main control factors were selected. The experiment was set up as an $L_9(3^4)$ orthogonal array, and determined the optimal levels of the four factors through the analysis of the experimental results. As a result, the performance characteristic(close adhesion power) of the product was improved about 36%. In addition, the process capability index $C_{pk}$ is enhanced from 0.94 to 6.85.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.214-230
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• 2014

This paper presents a high performance sensor less control four motorized wheels for electric vehicle. Firstly, we applied a sensor less master-slave DTC based control to both the two in wheel motors by using sliding mode observer for its quick response and its high reliability in electric vehicle application. Secondly, to overcome the possible loss of adherence of one of the four wheels which is likely to destabilize the vehicle a solution is proposed in this paper. Thirdly, a Fuzzy logic anti-skid control structure well adapted to the non-linear system is used to overcome the main problem of power train system in the wheel road adhesion characteristic. Various Simulation results have been include in this paper to show that the proposed control strategy can prevent vehicle sliding and show good vehicle stability on a curved path.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.2
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• pp.114-118
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• 2009

PVA (polyvinyl alcohol) brush cleaning method is a typical cleaning method for semiconductor cleaning process especially post-CMP cleaning. PVA brush contacts with the wafer surface and abrasive particle, generating the contact rotational torque of the brush, which is the removal mechanism. The brush rotational torque can overcome theoretically the adhesion force generated between the abrasive particle and wafer by zeta potential. However, after CMP (chemical mechanical polishing) process, many particles remained on the wafer because the brush was contaminated in previous post-CMP cleaning step. The abrasive particle on the brush redeposits to the wafer. The level of the brush contamination increased according to the cleaning run time. After cleaning the brush, the level of wafer contamination dramatically decreased. Therefore, the brush cleanliness effect on the cleaning performance and it is important for the brush to be maintained clearly.

• Elastomers and Composites
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• v.54 no.1
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• pp.30-34
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• 2019

Four different diisocyanates (IPDI; isophorone diisocyanate, HDI; hexamethylene diisocyanate, HMDI; dicyclohexylmethane-4,4'-diisocyanate, and XDI; m-xylylene diisocyanate) were used to prepare polyurethane gel-coats, and the weatherabilities, physical properties, and surface characteristics of the gel-coats were investigated with respect to the chemical structure of the diisocyanates. The weathering test results indicated that all of the diisocyanates used in this study were suitable for use in the preparation of the polyurethane gel-coat. However, the set-to-touch times and physical properties of the polyurethane gel-coat indicated that the cycloaliphatic diisocyanate (IPDI and HMDI) were ideal for the preparation of polyurethane gel-coats.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.75-76
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• 2020

In this study, in order to check whether the adhesion strength can be secured when installing concrete by mixing super-retarding agents, the splitting tensile strength of the joints of each mold was measured and then analyzed. The results of the experiment showed that the bonding performance of the joint is adversely affected if the installation delay is delayed for more than 24 hours, and that the attachment performance can be secured if the installation is delayed within about 24 hours.