• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.12
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• pp.927-934
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• 2014

In this paper, analysis of the vibration characteristic for the mine detectable test platform is described. The test platform system is the multi-sensor mine detectable vehicle. This multi-sensor mine detectable unit is more efficient detection performance than other conventional methods. The test platform system has five subsystems, the UWB(ultra wide band) sensor scanner, the MD(metal detector) sensor scanner, the ND(neutron detector) sensor scanner, and the detectable vehicle. We perform the vibration tests for the test platform and analyze the vibration characteristic, such as the max displacement, the max deformation and the max Von-Misses stress.

• Transactions of Materials Processing
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• v.12 no.6
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• pp.566-571
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• 2003

The metal forming behavior and defect formation in Ti-6Al-4V tube during hot backward extrusion were investigated. Dynamic material model(DMM) including Ziegler's instability criterion was employed to predict the forming defects such as shear band, inner and/or surface cracks. This approach was coupled to the internal variables generated from FE analysis. The simulation results fur the backward extrusion were compared with the experimental observation. The chilling effect and friction indicated a great influence on the deformation mode of the tube and the formation of surface cracks. The formation of forming defects in the extruded tube was attributed to non-uniform distribution of strain, strain rate and temperatures in the extruded tubes for the given test conditions.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.90-94
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• 2002

In this paper, Compression in the case where dissimilar blocks are twinned variously are carried out in the condition of lubricated interface. The degree of growth is experimentally investigated. Moreover, numerical simulations are carried out by the elastic-plastic FEM for the case of the dissimilar blocks with the initial sawtooth angle of 60。. The dissimilar blocks are twinned, larger difference between material properties leads smaller growth, and the degreased interface leads smaller growth than that in the lubricated one. Furthermore, by the simulation of compression where dissimilar blocks are twinned, it is confirmed that the tendency of the general deformation pattern is very similar to the experiment.

• Archives of Pharmacal Research
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• v.28 no.4
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• pp.458-462
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• 2005

The water content of skin was determined using a FT near infrared (NIR) spectrometer. NIR diffuse reflectance spectra were collected from hairless mouse, in vitro, and from human inner arm, in vivo. It was found that the variation of NIR absorbance band 1450 nm from OH vibration of water and 1940 nm from the combination involving OH stretching and OH deformation, depending on the absolute water content of separated hairless mouse skin, in vitro, using the FT NIR spectrometer. Partial least squares regression (PLSR) was applied to develop a calibration model. The PLS model showed good correlation. For practical use of the evaluation of human skin moisture, the PLS model for human skin moisture was developed in vivo on the basis of the relative water content of stratum corneum from the conventional capacitance method. The PLS model predicted human skin moisture with a standard errors of prediction (SEP) of 3.98 at 1130-1830 nm range. These studies showed the possibility of a rapid and nondestructive skin moisture measurement using FT NIR spectrometer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.10
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• pp.784-789
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• 2011

A linear spring model, where the interactions among atoms are assumed to be isotropic and elastic, is employed for the study of non-polar optical phonon scattering in the valence band of alloy semiconductors. The force equations of n atoms are used in the spring model for the consideration of the random distribution of constituent atoms in an alloy semiconductor. When the number of atoms in a unit cell is assumed to be two based on the experimental result, the optical deformation potent is valid for compound semiconductors as well as alloy semiconductors.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1262-1267
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• 1999

Optimum reaction conditions for gel formation of rapeseed, Brassica napus, protein catalyzed by microbial TGase(transglutaminase) were evaluated by measuring breaking strength and deformation of gel. The polymerization of the protein gel was ascertained by SDS-PAGE and content of GL crosslinking$[{\varepsilon}-({\gamma}-glutamyl)lysine]$. In the reaction between rapeseed protein and TGase at $45^{\circ}C$ for 60 min, the breaking strength and deformation of the gel was the maximum at the ratio of 1 : 40 of enzyme to substrate. 10%(w/v) of rapeseed protein concentrate was optimum for gel production. The maximum breaking strength and deformation was shown at $45^{\circ}C$ The breaking strength increased linearly up to 90 min of the reaction time and remained unchanged. The breaking strength and deformation by TGase treatment was pH dependent and pH 7 was optimum for 10% rapeseed protein solution. SDS-PAGE analysis indicated that new band of highmolecular polymers were formed by the enzyme reaction, with disappearing the original bands of rapeseed protein. According to HPLC analysis. the content of GL crosslinking was increased from 0 to $7.14\;{\mu}mol/g$ gel for 90 min of the reaction time.

• Korean Journal of Remote Sensing
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• v.32 no.6
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• pp.567-577
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• 2016

SqueeSAR is a new technique to combine Persistent Scatterer (PS) and Distributed Scatterer (DS) for deformation monitoring. Although many PSs are available in urban areas, SqueeSAR analysis can be beneficial to increase the PS density in not only natural targets but also smooth surfaces in urban environment. The height of each targets is generally required to remove topographic phase in interferometric SAR processing. The result of PSInSAR analysis to use PS only is not affected by DEM resolution because the height error of initial input DEM at each PSs is precisely compensated in PS processing chain. On the contrary, SqueeSAR can be affected by DEM resolution and precision since it includes spatial average filtering for DS targets to increase a signal-to-noise ratio (SNR). In this study we observe the effect of DEM resolution on deformation measurement by PSInSAR and SqueeSAR. With ALOS-1 PALSAR L-band data, acquired over Daejeon city, Korea, two different DEM data are used in InSAR processing for comparison: 1 m LIDAR DEM and SRTM 1-arc (~30 m) DEM. As expected the results of PSInSAR analysis show almost same results independently of the kind of DEM, while the results of SqueeSAR analysis show the improvement in quality of the time-series in case of 1-m LIDAR DSM. The density of InSAR measurement points was also improved about five times more than the PSInSAR analysis.

• Economic and Environmental Geology
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• v.35 no.5
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• pp.465-478
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• 2002

We measured subsidences occurred in a coastal reclaimed land, Noksan industrial complex, from May 2, 1996 to February 21, 1998, using 5 interferograms of JERS-1 L-band SAR. SAR with a spatial resolution of about 16 m can detect the two-dimensional distribution of subsidence that is difficult to be estimated from in situ measurements. Accuracy of the subsidences estimated by 2-pass DInSAR was evaluated using the measurements of Magnetic Probe Extensometer (accuracy of :${\pm}$1 mm) installed at 42 stations. DInSAR measurements were well correlated with the field measurements showing an average correlation coefficient of 0.77. The correlation coefficient was further improved to be 0.87 (with RMSE of 1.44 cm) when only highly coherenced (>0.5) pixels were used. The slope of regression line was 1.04, very close to the unit value. In short, DInSAR measurements have a good linear relation with field measurements so that we can effectively detect a subsidence in the coastal reclaimed area especially using pixels of high coherence (>0.5). The maximum accumulated subsidence was about 60 cm in the study area, while the subsidence in the northern and south western areas were less than 20 cm. The resuts show that DInSAR is extremely useful for geotechnical applications as well as observation of natural deformation.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.968-976
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• 2004

In the paper, deformation characteristics of fiber-mixed-soils, mixed polypropylene staple fibers of 0.3% fiber content with sands of various gradation, and their effectiveness of reinforcement were evaluated. A series of Resonant Column tests were performed with specimens prepared with varying Uniformity Coefficient and constant Curvature Coefficient. Maximum shear moduli 01 fiber-mixed-soils were increased by up to 30% and modulus reduction was also restrained in nonlinear range. Normalized shear modulus reduction curves of fiber-mixed-soils shift close to the upper limit of Seed curd Idriss's curves and are located within narrower band than those of unmixed soils, which proves the effectiveness on stiffness increment by reinforcing soils with fibers.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.542-545
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• 2005

Spaceborne radar interferometry has been widely used to estimate the topography and deformation of the Earth. It is difficult to obtain coherent interferometric SAR pairs especially over coastal areas mainly because of variation of surface conditions. We carried out the experiment using a cross-interferometric pair with a perpendicular baseline of about 1.4 km, a 30 minutes temporal separation and the height sensitivity of about 6 meters. The temporal decorrelation can be reduced by the cross interferometric technique with a 30 minutes temporal separation. Accurate coregistration was performed through resampling of ENVISAT ASAR data to equivalent pixel spacing to the ERS SAR data, because of the differences of the pulse repetition frequency and range sampling rate between the two sensors. Then we estimated range and azimuth offset to a sub-pixel accuracy using image intensity cross correlation. A larger window chip size than a general case was used because it was difficult to distinguish typical features. As range bin increased, the difference of Doppler centroid also increased. It resulted in lower coherence in far range than in near range. Coherences over wetland in near and far range were about 0.8 and 0.5, respectively. The coherence was improved by applying azimuth and range common band filtering, but coherence gap still existed. ERS-ENVISAT cross-interferogram usually lost information in urban area. However, high coherence over a city in this pair was shown, because of less man-made structures than other major cities. Accuracy of the DEM constructed by the ERS-ENVISAT 30-minute pair in a coastal area is to be evaluated.