• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.11
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• pp.1071-1077
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• 2010

The reduction of the vehicle interior noise has been the main interest of noise and vibration harshness(NVH) engineers. A passenger vehicle has various and complicated transmission paths of sound and vibration. In order to identify the mechanism of transfer path, estimation of excitation force and exact modeling of transfer path are required. This paper presents method for estimating the noise source contribution on the road noise of the vehicle in a multiple input system where the input sources may be coherent with each other. And vector synthesis technique is employed to identify the characteristics of road noise and its transmission to vehicle compartment through noise and vibration analysis. Vibration reduction efficiency of each transfer path is evaluated by comparing individual vector components obtained virtual simulation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.361-364
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• 2011

In this paper, This work demonstrates a experimental evaluation for vehicle road noise NVH performance from the component-level NVH measurements of Tire. The power unit noise from tire emitted by cars has been reduced. It has been found that tire noise dominates noise produced by the power train when vehicles are driven at high constant speed. Therefore tire pattern noise is affected by pattern and vehicle and transmission loss. Tire noise mechanism is generated by several mechanisms. The sound of tire can propagate either through the air or through the structure of vehicle. Pattern noise is the result of pressure variations through the air to the interior side of vehicle. Especially, smooth asphalt, the periodicity of tread design, groove depth is important factor, which have an influence on the reduction of tire pattern noise.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.1023-1027
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• 1996

In this paper, the new technology and R&D status is presented, which accelerates the projectile using the electrical energy to overcome the limit of the conventional gun. The ETC (electro_thermal_chemical) gun, one kind of electric guns, seems to be the highly probable candidate as the next generation gun. The high density power supply and the forming and control of the current pulse are required to develop the ETC gun. And, the interior ballistics considered the mechanism of ETC gun must to be studied.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.340-343
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• 2006

As the needs of consumer on ride comforts increase and the reduction of road traffic noise tightened step by step, the power unit noise emitted by cars has been reduced. It has been found that tire noise dominates noise produced by the power-train when vehicles are driven at high speeds. Therefore, in these days, tire/pavement noise is concerned. Tire/pavement noise is affected by pavement type and vehicle???s transmission loss. Tire noise mechanism is produced by several mechanisms. The sound of tire can propagate either through the air or through the structure of vehicle. Pattern noise is the result of pressure variations through the air to the interior side of vehicle. Especially, on smooth asphalt the periodicity of tread design, pitch sequence is important factor, which have an influence on the reduction of tire noise.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.58-63
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• 2002

For the experiment the four types of spacer were distinguished by arrangement. The flashover characteristic on each types of spacer was investigated and the flashover phenomena were observed to understand breakdown mechanism in liquid nitrogen($LN_{2}$). The spacer should be placed interior coil as an insulator, a cooling channel and s supporter of structures. The simulated electrode used in the experiment was made from five turns of HTS tape. Experimental results revealed that multi-layer and barrier effects did work well in Air but did not in $LN_{2}$. These result suggested that the flashover in LN2 caused by the bubbles due to partial discharge at micro gap, g. The flashover characteristics decreased to 70% when g is 0.2 mm. The degradation was improved by even treatment on surface of coil electrode.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.600-604
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• 2013

A CTBA(Coupled Torsion Beam Axle) is a general type for rear suspension of small/compact sedans. It connects left and right knuckles using torsion beam axle and trails rear wheels. Therefore, a CTBA performs a main role of ride & handing. But, a CTBA suspension has main bending mode around 120Hz and causes road booming noise in the interior of a car. Therefore, the mode control of a CTBA is very important for reducing road noise. In this paper, we optimized the shape of a CTBA to reduce road noise considering R&H performance, simultaneously. The vibration mechanism of CTBA was investigated using ODS(Operational Deflection Shape) and mode shape.

• Journal of the Korean institute of surface engineering
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• v.8 no.1
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• pp.15-23
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• 1975

Electrodeposition of metals form aqueous solutions (eg, electroplating ) is frequently accompanied, by the discharge of hydrogen ions(in acidic solutions) or water molecules ( in alkaline electrolytes). The atomic hydrogen produced thus may partly diffuse into the interior of the substrate and when this is absorbed by iron/steel substrate, it has detrimental effects on the mechanical properties of the steel, leading to ahydrogen embrittlement. Steels, particularly the high strength steels, are prone to hydrogen embrittlement. In view of the increasing applications of high strength steels in variousindustries, particularly in the aircraft manufacture, there has been renewed interest in the studiesonhydrogen embrittlement during electroplating of metals. In this review, the author summarizes the reports on hydrogen embrittlement during preplating of metals. In this review , the author sumamrizes the hydrogen embrittlement during electroplating of metals. In this review , the author summarizes the reports on hydrogen embrittlement during preplating operations and electroplating of metals like copper, nickel, tin, zinc ,cadimum and chromium. Finally, the effect of degassing by baking to deembrittle the plated high tensile steels and mechanism of hydrogen embrittlement are briefly indicated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.29-30
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• 2019

The indoor air quality of modern people who work indoors more than 80 percent a day has also become a very important factor in their lives. But most indoor air quality is highly polluted due to energy conservation and lack of ventilation. This can lead to pneumonia, asthma and even lung cancer, which can be fatal to children, the elderly and the elderly. Indoor pollutants are caused by boards, wallpaper, paint, etc. used in interior By producing indoor finishing materials using active alumina gel, which is used as dehumidifier, indoor pollutants will be reduced and the possibility of developing respiratory diseases and lung cancer will be reduced.

• Korean Institute of Interior Design Journal
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• v.21 no.1
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• pp.40-50
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• 2012

This study aims at suggesting the applicability of color combination based upon the characteristics of environmental color perception and the nuance concept of Natural Color System(NCS). The results are summarized below: First, NCS is a scientific coloring system in consideration of the relevance between people, light and environment, to be based on a phenomenological point of view. NCS can be called a psychometric model reflecting our natural color sense. Second, the color triangle established by NCS is one of the methods of expression based on the human visual mechanism, which is classified by two attributes of hue and nuance, not by the three color attributes of hue, lightness and saturation. The nuance concept of NCS implies the impression, atmosphere and tone that are perceived in colors, which are related to lightness and saturation. Accordingly, this paper suggests that the coloring arrangement emphasizing nuance and tone is more useful than hue in color planning. Third, aesthetic impression in environmental color perception is inclusive of instantly perceptive nuance, which is connected with affordance. The affordance is revealed by the different relation of similarity. In this regard, a strong relationship is noticed between color combination and the sense of pleasantness. The hypothesis regarding the complementation and similarity of contrasting nature is judged to provide observers with aesthetic order. Finally, this paper also suggests four harmonizing methods in the NCS color triangle based upon equal blackness, equal whiteness, equal chromaticness and same nuance. At the same time, opposition and a different concept of hue, lightness and lightness are combined complementarily with the nuance value to suggest patterns of color combination.

• Korean Institute of Interior Design Journal
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• v.19 no.2
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• pp.90-98
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• 2010

The concepts of laws like regularity or persistence or recurrence those are discovered in nature, became the essential elements in speculative philosophy, study and scientific technology. Western civilization was spread out by these natural laws. As this background, this study is aimed to research the theories of natural laws and the development of geometry as the descriptive tools and the development aspects of the concepts of space. According to Whitehead's four theories on the natural laws, the result of this study that aimed like that as follows. First, the theories on the immanence and imposition of the natural laws were the predominant ideas from ancient Greek to before the scientific revolution, the theory on the simple description like the positivism made the Newton-Cartesian mechanism and an absolutist world view. The theory on the conventional interpretation made the organicism and relativism world view according to non-Euclidean geometry. Second, the geometrical composition of ancient Greek architecture was an aesthetics that represented the immanence of natural laws. Third, in the basic symbol of medieval times, the numeral symbol was the frame of thought and was an important principal of architecture. Fourth, during the Renaissance, architecture was regarded as mathematics that made the order of universe to visible things and the geometry was regarded as an important architectural principal. Fifth, according to the non-Euclidean geometry, it was possible to present the natural phenomena and the universe. Sixth, topology made to lapse the division of traditional floor, wall and ceiling in contemporary architecture and made to build the continuous space. Seventy, the new nature was explained by fractal concepts not by Euclidean shapes, fractal presented that the essence of nature had not mechanical and linear characteristic but organic and non-linear characteristic.