• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.826-831
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• 2002

In order to investigate the dynamic characteristics of real structure, many dynamic engineer had been interested in modal test however it is not easy to perform dynamic test of large structure because of many difficulties such as unsatisfied excitation force in global mode frequency range, measurement of dynamic force and so on. Therefore. new type vibration exciter with variable stiffness support system and dynamic force was developed to provide a improved experimental environment for a large and complex structure. The developed exciter improved from two viewpoint, dynamic performance and utility convenience. its characteristics was shown in this paper.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.687-692
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• 2002

In order to verify the effectiveness of adding visooelastic dampers to full-scale steel frame structure on the reduction of their seismic and wind response a experimental work was carried out. First, The test was conducted on the VE dampers subjected to sinusoidal excitations under a variety of ambient temperatures, frequency, and the damper strain. Results from these tests showed that the viscoelastic dampers have high energy dissipation capacity. Second, The vibration tests was conducted of the full-scale steel frame structure with md without added VE dampers at different temperatures. Viscoelastically damped full-scale structure test result on the effect of ambient temperature show that viscoelastic dampers are very effective in reducing excessive vibration of the structure due to sinusoidal excitation over a wide ringe of ambient temperature.

• Smart Structures and Systems
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• v.15 no.4
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• pp.949-961
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• 2015

The goal of this study is to present numerical modeling and analytical testing in order to evaluate an innovative space truss typed temporary structure, which is used to maintenance and repair of road tunnels. The present space truss structure has merits to use UL-700 high strength steel tube as members and to carry out maintenance and repair works of road tunnels without blocking cars and transportations. Numerical modeling and analytical testing of the space truss are investigated by using commercial engineering software, i.e., ABAQUS 6.5-1, and then it is verified that the truss structure has both structural safety and effective function for maintenances and repairs of road tunnels.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.1050-1053
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• 2002

This paper presents metal structure that is fabricated using UV-LIGA process with PMER N-CA3000. In order to fabricate metal structure with high aspect ratio, the systematic optimization method was adopted and then the structure of $36{\mu}m$ thick mold with aspect ratio 7:1 (trench) and $32{\mu}m$ thick nickel structure was obtained. This structure is applied to the fabrication of optical switch.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.82-82
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• 2014

One of the subjects in clouds' structure and development is small scale structure of interstellar cloud. The possibility of AU scale structure (Marscher et al. 1993; Moore & Marscher 1995; Roy et al. 2012) is discussed, and this small scale structure is considered as the result of hydrogen volume density (Moore & Marscher 1995), or small-scale chemical and other inhomogeneities (Liszt & Lucas 2000). In order to study this subject with emission line, extremely high resolution is mandatory by VLBI system. However, the alternative method could be observing the absorption line of interstellar cloud on the continuum object. In this case, the resolution would be restricted to the size of the continuum object, if the size of the object is smaller than the resolution of a used telescope. We observed the previous researchers' three objects (BLLAC, NRAO150, B0528+138), whose spectrums are changed from 1993 to 1998 (Liszt & Lucas 2000), with KVN. Through KVN observation, we found the changes of optical depth spectrum compared with the previous spectrums. We will discuss the optical depth spectrum variation by time variation and the meaning of it.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.65-68
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• 2008

In this study, in order to improve luminous efficacy of AC-PDP, the new facing discharge structure has been suggested. The suggested structure has tilted facing electrode. It shows lower discharge current, higher luminance and luminous efficacy compared with those of reference structure with coplanar electrode structure.

• Journal of Korean Association for Spatial Structures
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• v.1 no.2 s.2
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• pp.101-110
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• 2001

A large floating structure is attracting great attention in recent years from the view of ocean space utilization. Its huge scale in the horizontal directions compared with the wavelength and relatively shallow depth make this type of floating structure flexible and its wave-induced motion be characterized by the elastic deformation. In this paper, a boundary integral equation method is proposed to predict the wave-induced dynamic response mat-like floating offshore structure. The structure is modeled as an elastic plate and its elastic deformation is expressed as a superposition of free-vibration modes in air. This makes it straightforward to expand the well-established boundary integral technique for rigid floating bodies to include the hydroelastic effects. In order to validate the theoretical analysis, we compare with the experimental result of reduced model test. Satisfactory agreement is found between theory and experiment.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.113-116
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• 2005

In this study, in order to. investigate the effectiveness af tuned liquid damper (TLD) for the seismic performance enhancement af the existing reinforced concrete (RC) apartment structure which is nat seismically designed, shaking table test was conducted for the small scale five stary RC structure with TLD. TLD model was constructed to. have the frequency tuned to. the first modal frequency af the structure, $2\%$ mass ratio. af the first modal mass, and 0.08 liquid depth ratio. White noise with $0.2\~5Hz$ frequency bandwidth tests were performed using the shaking table at Korea Institute af Machinery and Materials, and the displacement and absolute acceleration af each floor were measured. Test results indicate that mare than $30\%$ seismic responses reduction can be achieved using TLD for RC structure under white noise.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.11
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• pp.531-535
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• 2002

Nowadays, the most serious problems in ac PDP are high cost and complex manufacturing processes. To solve these problems, fence electrode structure, which eliminates the need for expensive transparent electrodes, has been newly suggested. But it has a lower luminance and luminous efficiency than the conventional stripe type electrode structure. In this study, an improved fence electrode structure has been suggested in order to improve luminance and luminous efficiency. The experimental results show that the luminous efficiency of suggested structure is 25% higher than that of conventional fence electrodes.

• Journal of the Korean Society of Costume
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• v.59 no.1
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• pp.136-145
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• 2009

Growing needs of reducing energy consumption and enhancing creative thinking brought expanding of men's business wear market into more trendy and casual sector. As fashion trend of men's business wear has changes to casual jackets, there is need to study for the inner structure of casual jacket. The inner structure of casual jackets are different from conventional tailored jackets so that they can provide more comforts, functionality and characteristic style. The purpose of this study is to find out how the inner structure of casual jackets are made up by comparing jackets of various brands. In order to categorize the construction methods, where, how and what kind of lining, interlining, sleeve heads and shoulder pads are applied were studied. Although there are considerable varieties in making up methods, it could be concluded that casual jackets have lighter and less time and labour consuming inner structure, i.e. partial linings, fusible inter-linings, ready made sleeve heads and shoulder pads.