• Earthquakes and Structures
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• v.7 no.3
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• pp.365-384
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• 2014

The intensity of a ground motion can be measured by a number of parameters, some of which might exhibit robust correlations with the damage of structures subjected to that motion. In this study, 204 near-fault pulse-type records are selected and their seismic parameters are determined. Time history and damage analyses of a tested 3-storey reinforced concrete frame representing for low-rise reinforced concrete buildings subjected to those earthquake motions are performed after calibration and comparison with the available experimental results. The aim of this paper is to determine amongst several available seismic parameters, the ones that have strong correlations with the structural damage measured by a damage index and the maximum inter-story drift. The results show that Velocity Spectrum Intensity is the leading parameter demonstrating the best correlation, followed by Housner Intensity, Spectral Acceleration and Spectral Displacement. These seismic parameters are recommended as reliable parameters of near-fault pulse-type motions related to damage potential of low-rise reinforced concrete structures. The results also reaffirm that the conventional and widely used parameter of Peak Ground Acceleration does not exhibit a good correlation with the structural damage.

• Korean Journal of Optics and Photonics
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• v.17 no.5
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• pp.391-395
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• 2006

In this paper, radiometric calibration of a FTIR spectrometer for passive remote sensing application was introduced and verified. Radiometric calibration is a significant signal processing procedure to retrieve the object radiance from the measured spectrum. The object radiance is measured and registered distorted by the detector's responsivity dependent on wavelength and instrument self-emission. Radiance of two temperature points, hot temperature and cold temperature, from a well-controlled blackbody was measured and used to obtain the scale factor and offset factor which are required for radiometric calibration. For gas phase C2H5OH. radiometric calibration was done and verified through comparison of its emission line width and intensity with the standard spectrum.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1998.06b
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• pp.122-128
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• 1998

• The Bulletin of The Korean Astronomical Society
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• v.32 no.1
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• pp.88.2-88.2
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• 2007

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.728-731
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• 2005

The objective of this paper is to perform measurements of vibration intensity of a coupled beam. The propagation of flexural waves generates the out of plane vibration of the coupled beam. The longitudinal waves are generated due to the mode conversion at the structural joint of the coupled beam. The propagation of longitudinal waves generates the in plane vibration of the coupled beam. In order to identify the direction of vibrational power on the coupled beam, the in plane vibration intensity as well as the out of plane vibration intensity needs to be measured. The cross spectral method has been implemented to measure the in-plane vibration intensity as well as out of plane vibration intensity. The results shelved that the experimental method can be effectively used to measure the in-plane vibration intensity as well as the out of plane vibration intensity of coupled beams.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.06a
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• pp.1-14
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• 1993

Ground reinforcements is the essential method to prevent the liquefaction of loose sand deposit, However, in the construction of the life lines, it is impossible to treat the whole loose deposit against liquefaction. As an countmeasure for the life lines against the liquefaction, a monitorning system can be considered for an immediate judgement of the liquefaction occurrence during an earthquake. Through shaking table tests on model grounds, pore presure developments were investigated in terms of the surface spectral velocity, which was verified as a tool for the immediate judgement of the liquefaction occurrence.

• ETRI Journal
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• v.33 no.4
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• pp.497-505
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• 2011

Image fusion is a technical method to integrate the spatial details of the high-resolution panchromatic (HRP) image and the spectral information of low-resolution multispectral (LRM) images to produce high-resolution multispectral images. The most important point in image fusion is enhancing the spatial details of the HRP image and simultaneously maintaining the spectral information of the LRM images. This implies that the physical characteristics of a satellite sensor should be considered in the fusion process. Also, to fuse massive satellite images, the fusion method should have low computation costs. In this paper, we propose a fast and efficient satellite image fusion method. The proposed method uses the spectral response functions of a satellite sensor; thus, it rationally reflects the physical characteristics of the satellite sensor to the fused image. As a result, the proposed method provides high-quality fused images in terms of spectral and spatial evaluations. The experimental results of IKONOS images indicate that the proposed method outperforms the intensity-hue-saturation and wavelet-based methods.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.1
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• pp.43-52
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• 2021

According to several seismic design standards, a ground motion time history should be selected similar to the design response spectrum, or a ground motion time history should be modified by matching procedure to the design response spectrum through the time-domain method. For the response spectrum matching procedure, appropriate seed ground motions need to be selected to maintain recorded earthquake accelerogram characteristics. However, there are no specific criteria for selecting the seed ground motions for applying this methodology. In this study, the characteristics of ground motion time histories between seed motions and spectral matched motions were compared. Intensity measures used in the design were compared, and their change by spectral matching procedure was quantified. In addition, the seed ground motion sets were determined according to the response spectrum shape, and these sets analyzed the response of nonlinear and equivalent linear single degrees of freedom systems to present the seed motion selection conditions for spectral matching. As a result, several considerations for applying the time domain spectral matching method were presented.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.1185-1188
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• 2002

The objective of this paper is to apply experimental methods to measure the in-plane vibration intensity of a semi-infinite beam. Two experimental methods have been implemented to measure the in-plane vibration intensity of the beam. The first method is the cross spectral intensity measurement method using two accelerometers. The second method is the frequency response method using the only one acrelerometer. It has the advantages of shortening measurement time and reducing accelerometer phase error. Experimental results showed that those experimental methods can be effectively used to measure the structural In-plane vibration intensity.

• Bulletin of the Korean Chemical Society
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• v.9 no.2
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• pp.106-108
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• 1988

The effects of surfactants, CTAB, SDS, and TX-100, on the fluorescence emission intensity of Be-morin complex was studied in terms of pH, temperature, added electrolyte, and concentration of surfactants. The ionic surfactants decreased the fluorescence intensity of the complex. However, the addition of TX-100 caused a substantial increase in the fluorescence intensity without spectral shift, by which means the detection limit of Be was obtained to be 0.3 ppb. Optimum pH for Be determination was near 9.6 and the fluorescence intensity showed a continuous decline with the increase of temperature. Nitrate ion lowered the fluorescence intensity considerably. Mechanism of the interference remains to be elucidated.