• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2965-2972
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• 2011

The 21th century is carried out a rearing activity of green industries as a part of friendly echo policy for preservation of earth environment. Korean government is spreaded on a whole country to setting up a goal to a sustainable growth power of national for low carbon green growth. The recently rolling stock is received the footlights as a best friendly echo transportation of transport system of automobile, airplane, ship etc., also that is playing a big role to reduction of $CO_2$ greenhouse gas and a discharge of air pollution. This study was carried out the investigation and analysis for technology trend of the system light-weighting of a recently urban railway vehicle on commercial operating in domestic and foreign countries. As the results are proposed a short-term development technology and a long-term development technology of the system light-weighting to be developed for reduction weight of urban railway vehicle.

• Transactions of Materials Processing
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• v.26 no.1
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• pp.55-62
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• 2017

This paper proposes the process to develop a light-weighting automotive door assembly using high strength steel with low cost penalty. In recent years, the automotive industry is making an effort to reduce the vehicle weight. In this study, inner panels for automotive front door using thinner sheets and quenchable boron steel were designed to reduce the weight of conventional one. In order to evaluate the stiffness properties for the proposed door design, the several static tests were conducted using the finite element method. Based on the simulation results, geometry modifications of the inner panels were taken into account in terms of thickness changes and cost saving. Furthermore, a prototype based on the proposed design has been made, and then static stiffness test carried out. From the results, the proposed door is proved compatible and weight reduction of 11.8% was achieved. It could be a reference process for automotive industry to develop the similar products.

• Textile Coloration and Finishing
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• v.9 no.6
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• pp.51-57
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• 1997

The lightness, chroma and hue tolerances with respect to the standard colour position in the CIELAB space have been studied in detail using the various existing data sets and the set form this study. The lightness tolerance showed a clear dependency upon the metric lightness for medium to light colour, but in the case of dark colours there was a discrepancy between the data sets. Both the chroma and hue tolerances showed dependency upon both the chroma and hue-angle and not the single dependency upon the metric chroma, as assumed in the CIE94 formula. New weighting functions were derived from the above experimental evidence, and finally a new formula, LCD(Leeds Colour Difference) was proposed. The LCD formula is nearly as simple and flexible as CIE94 but smoothes the individual weighting functions, especially for lightness tolerances for light colours and chromaticity discrimination near the blue region.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.291-294
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• 2005

In this study, we compared and analyzed the floor impact sound insulation performance produced by the rating methods. The rating methods are using reversed A-weighting curve, A-weighted sound pressure levels and arithmetic average. On-site floor impact sound pressure levels of living room and room are measured. The results of this study are 1)the rating using reversed A-weighting curve for heavy-weight impact sound's standard deviation is lower than that of light-weight impact sound, 2)the number of rating using A-weighted sound pressure levels and arithmetic average is larger than that of using reversed A-weighting curve, and 3)the number of rating using reversed A-weighting curve mainly depends on impact sound pressure level of 63Hz in heavy-weight impact sound.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.612-615
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• 2006

In this study, we compared and analyzed the floor impact noise insulation performance produced by the rating methods. The rating methods are using reversed A-weighting curve, A-weighted sound pressure levels(dB(A)). The results of this study are(1)dB(A) by the specified frequency is 0.5dB(A) at light weight and 2.5dB(A) at heavy weight upper than all pass dB(A)(2)the rating using reversed A-weighting curve is 5dB lower than dB(A)(3)the number of rating using reversed A-weighting curve mainly depends on impact noise pressure level of 63Hz in heavy weight but dB(A) does not.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.4
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• pp.347-353
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• 2008

Reflected light can be decomposed into specular and diffuse components according to the light reflectance theory and experiments. The specular component appears in smooth surfaces mainly, while the diffuse one is visible in rough surfaces mostly. Therefore, each component can be used in forming their correlations to a surface roughness. However, they cannot represent the whole surface roughness seamlessly, because each formulation is merely validated in their available surface roughness regions. To solve this problem, new approaches to properly blend two light components in all regions are proposed in this paper. First is the weighting function method that a blending zone and rate can be flexibly adjusted, and second is the neural network method based on the learning from the measurement data. Simulations based on the light reflectance theory were conducted to examine its performance, and then experiments conducted to prove the enhancement of the measurement accuracy and reliability through the whole surface roughness regions.

• Composites Research
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• v.28 no.5
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• pp.322-326
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• 2015

We developed the high-power LED beacon and investigated the applicability of composite materials for the light-weight design of LED beacon. By means of the application of composite materials, the vertical deformation could be reduced by 17% and the total weight of LED beacon 8.9 kg comparable to 20% light-weighting against aluminum beacon. In thermal radiation test, the maximum temperature of LED package was measured to $63.5^{\circ}C$ under ambient temperature ($20^{\circ}C$), which is acceptable considering both performance and lifespan of LED packages. In this study, the applicability of composite materials was demonstrated for light-weight design of high-power LED beacon.

• The monthly packaging world
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• s.358
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• pp.91-95
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• 2023

• Journal of Korea Foundry Society
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• v.31 no.3
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• pp.101-105
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• 2011

• The monthly packaging world
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• s.312
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• pp.71-75
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• 2019