• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.53.4-53
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• 2001

This paper described about the system which can be inspect work roll surface for deciding a milling schedule and roll changing at hot strip mill in POSCO. Developed system consists of CCD camera, Xenon lamp with fiber bundle and mechanical control part. The water probe build up water pole between head of probe and roll surface to acquisite a good image from a work roll surface under the bad environment with steam, cooling water and high temperature. This system is possible to monitor a work roll surface of about 12${\times}$9mm. We have shown the validation of the developed system which can monitor the evolution of degradation on work roll surface.

• KSBB Journal
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• v.27 no.3
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• pp.145-150
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• 2012

This study was accomplished using packed bed column reactors that contain nonsurface-modified polypropylene media and surface-modified media from hydrophobic surface property into hydrophilic property by ion beam irradiation. The objectives of this research was investigated the characteristics of organic compounds removal and microbe attachment from sewage of school cafeteria in these reactors. In 736.8 mg/L of the average inflow $COD_{Cr}$ concentration the reactors with and without surface modification showed 81.8% and 70.3% of average $COD_{Cr}$ removal efficiencies, respectively, which proves the $COD_{Cr}$ removal efficiency of surface-modified media reactor is higher than that of nonsurface-modified media reactor. After 90 days, there were maximum differences between modified system and non-modified system. In that time the maximum removal efficiency of $COD_{Cr}$ was 96.5% in modified system and was 85.2% in non-modified system that showed removal efficiency of surface-modified media system is 11.3% higher than that of nonsurface-modified media system. The average removal efficiency of SS was 80.4% for the surface modified system and 61.6% for the non-modified system under same condition. Also, the reactor of surface-modified media has advantage on microbe attachment and biofilm formation.

• Journal of computational fluids engineering
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• v.12 no.4
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• pp.68-73
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• 2007

Computational Fluid Dynamics (CFD) approach is now playing an important role in the engineering process in these days. Generating proper grid system in time for the region of interest is prerequisite for the efficient numerical calculation of flow physics using CFD approach. Grid generation is, however, usually considered as a major obstacle for a routine and successful application of numerical approaches in the engineering process. CFD approach based on the unstructured grid system is gaining popularity due to its simplicity and efficiency for generating grid system compared to the structured grid approaches, especially for complex geometries. In this paper an automated triangular surface grid generation using CAD(Computer Aided Design) surface data is proposed. According to the present method, the CAD surface data imported in the STL(Stereo-lithography) format is processed to identify feature edges defining the topology and geometry of the surface shape first. When the feature edges are identified, node points along the edges are distributed. The initial fronts which connect those feature edge nodes are constructed and then they are advanced along the CAD surface data inward until the surface is fully covered by triangular surface grid cells using Advancing Front Method. It is found that this approach can be implemented in an automated way successfully saving man-hours and reducing human-errors in generating triangular surface grid system.

• Science of Emotion and Sensibility
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• v.2 no.1
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• pp.105-111
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• 1999

In order to introduce the touch to engineering and industries, it must be preceded to dstablish a quantitative barometer of the feeling. for this purpose, we developed a tactile measuring system to measure physical properties of texture, such as surface roughness, friction coefficient and compliance. The tactile measuring system uses a LASER type displacement sensor, which is a non-contacting system, in measuring the surface roughness. By considering that human tactile system is a contacting mechanism, this non-contacting method needs to be modified. As a precedent research of that, we compared the contacting and non-contacting method in this paper. Surface roughness of ten cloths were measured by using the measuring system, then compared to the test results using the Kawabata evaluation system(KES), which uses a contacting method in measuring the surface roughness.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.10
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• pp.68-74
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• 1997

The surface finishing system using the micro abrasive film was designed and manufactured to make the mirror surface of the cylindrical workpices. An experimental study of srface finishing was carried out to investigate the performance of mirror surface finishing system. The surface roughness value of stainless steel was about 0.2 .approx. 0.25 .mu. m Rmax, 0.02 .approx. 0.04 .mu. m Ra, using abrasive grain size of 12, 9 .mu. m. The surface roughness value of chrome coated workpiece was about 0.07 .approx. 0.11 .mu. m Ra using abrasive grain size 3 .mu. m. In the same condition, the chrome coated workpiece has obtained better surface roughness charateristics than the one of stainless steel.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1099-1104
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• 2004

As consumer in optics, electronics, aerospace and electronics industry grow, the demand for ultra precision aspherical surface lens increases higher. To enhance the precision and productivity of ultra precision aspherical surface micro lens, the following specification of ultra precision grinding system is required: the highest rotational speed of the grinder is 100,000rpm and its turning accuracy is $0.1{\mu}m$, positioning accuracy is $0.1{\mu}m$. The development process of the grinding system for the ultra precision aspherical surface micro lens for optoelectronics industry is introduced. In the work reported in this paper, an intelligent grinding system for ultra precision aspherical surface machining was designed by considering the factors affecting the surface roughness and profiles accuracy. An aerostatic form was adopted to build the spindle of the workpiece and the spindle of grinder and ultra precision LM guide way was adopted in this system.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.2
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• pp.53-60
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• 1998

In this study, it is experimented to find factors effecting surface roughness using the system of experiments. in the mirror surface finishing system. (1) The film feed and oscillation frequency in $40{\mu}m$ abrasive film, grinding speed in $30{\mu}m$, and machining time in $15{\mu}m$15 are the main factors effecting the surface roughness. (2) Applying the optimal finishing condition to $40{\mu}m$, $30{\mu}m$, $15{\mu}m$ abrasive finishing film in sequence, it is possible to obtian about Ra 10 nm surface roughness on SM45C workpiece. (3) Application of the system of experments to the micro abrasive grain film finishing was very effective method in the extraction of main factor and optimal condition.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.6
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• pp.514-521
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• 2000

In this study, a surface generating system with a bundle of wires, which can reproduce a certain range of surface roughness of the objects without direct machining process, is implemented. The system consists of a bundle of wires, a PZT actuator, a vertical table system actuated linearly along two perpendicular axes, and an image processing system. Through the development of the operational software for all of those subsystems by a common language(Visual C＋＋) of the implemented system, the complete process except arrangement of a bundle of wires are automated. Lastly, through the experiments of generating the flat surface of some virtual object and then of measuring the reproduced surface roughness, it is confirmed that the implemented system has excellent performance.

• Journal of the Korean Solar Energy Society
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• v.29 no.6
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• pp.88-93
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• 2009

This study was conducted to improve the power of PV module using a surface cooling system One of the unique characteristics of PV module is power drop as a module surface temperature increases due to the characteristics of crystalline silicon used in a solar cell. To overcome the output power reduction by temperature effect, module surface cooling using water circulation was performed. By cooling effect, module surface temperature drops maximally $20.3^{\circ}C$ predicting more than 10% power enhancement. Maximum deviation of voltage and current between a control and cooled module differed by 5.1 V and O.9A respectively. The maximum power enhancement by cooling system was 12.4% compared with a control module. In addition, cooling system can wash the module surface by water circulation so that extra power up of PV module can be achieved by removing particles on the surface which interfere solar radiation on the cells. Cooling system, besides, can reduce the maintenance cost and prevent accidents as a safety precaution while cleaning works. This system can be applied to the existing photovoltaic power generation facilities without any difficulties as well.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.309-313
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• 2009

This study was conducted to improve the power of PV module using a surface cooling system. One of the unique characteristics of PV module is power drop as a module surface temperature increases due to the characteristics of crystalline silicon used in a solar cell. To overcome the output power reduction by temperature effect, module surface cooling using water circulation was performed. By cooling effect, module surface temperature drops maximally $20.3^{\circ}C$ predicting more than 10% power enhancement. Maximum deviation of voltage and current between a control and cooled module differed by 5.1V and 0.9A respectively. The maximum power enhancement by cooling system was 12.4% compared with a control module. In addition, cooling system can wash the module surface by water circulation so that extra power up of PV module can be achieved by removing particles on the surface which interfere solar radiation on the cells. Cooling system, besides, can reduce the maintenance cost and prevent accidents as a safety precaution while cleaning works. This system can be applied to the existing photovoltaic power generation facilities without any difficulties as well.