• Clinical and Experimental Pediatrics
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• v.51 no.8
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• pp.861-867
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• 2008

Purpose : We carried out this study to determine if there is any difference in the occurrence rate of the epileptiform discharge between awake EEG and sleep EEG and if there are any factors influencing on the occurrence rate of EEG. Methods : This study included 178 epileptic children who had visited neurology clinic of the department of pediatrics, Pusan National University Hospital from July 2005 to July 2006. The medical and EEG records of these children who had had both awake EEG and sleep EEG were reviewed. We analysed the occurrence rate of the epileptiform discharge between awake EEG and sleep EEG. We investigated the related clinical factors which included sex, seizure types, underlying causes, age at first seizure, antiepileptic drug (AED) medication, age at recording, and background activity. Results : Among 178 epileptic children, 91 patients (51.1%) showed epileptiform discharge in awake or sleep states, 10 patients (11.0%) abnormal only in awake, 40 patients (44.0%) abnormal only in sleep, 41 patients (45.0%) abnormal in both awake EEG and sleep EEG. The occurrence rate of sleep EEG was 81 of 178 patients (45.5%) which was more than that of the awake EEG (28.7%) (P<0.001). The occurrence rate of sleep EEG is more than that of the awake EEG regardless of sex and underlying causes. But there is no significant difference from awake EEG and sleep EEG in finding the epileptiform discharge in the patient with generalized seizure, younger than 5 years old at first seizure, younger than 10 years old at recording, no antiepileptic medication, and abnormal background activity. Conclusion : The sleep EEG is thought to be more helpful in the diagnosis of childhood epilepsy.

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.124.2-124.2
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• 2009

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.88-88
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• 2009

• Journal of the Institute of Convergence Signal Processing
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• v.3 no.3
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• pp.6-13
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• 2002

In this paper, we propose an image processing based method to measure red-time and green-time backward moving shockwave speed automatically at signalized intersections. Shockwave means the discontinuous boundary line between different vehicle traffic flows, and its moving speed is called shockwave speed which is obtain from the slope of boundary line. In this paper, we compose distance-time diagram for measuring shockwave speed automatically. By global vehicle tracking, we draw all of the vehicle moving path on distance-time diagram. We analyze the slope change pattern of curved moving path line, and compute red-time and green-time backward moving shockwave speed. We obtain the measurement result of shockwave speed, when applying above mentioned proposed method to experiment at signalized intersections, Once we can measure the shockwave speed, we could apply the result to highway ramp metering and automatic signal control at intersections effectively since we know the situation of frontal congestion easily.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.89-93
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• 2016

In this study, we investigated the separation behavior of the anticancer agent paclitaxel and its semi-synthetic precursor 10-deacetylpaclitaxel (10-DAP) from plant cell cultures. As a result of sequential separation/purification performed by biomass extraction with solvent, liquid-liquid extraction, adsorbent treatment, hexane precipitation, and fractional precipitation, the adsorbent treatment was found to be the most effective in separating and recovering 10-DAP from paclitaxel. The optimal adsorbent type, crude extract/adsorbent ratio, and adsorbent treatment temperature were sylopute, 1:1.5 (w/w), and $20^{\circ}C$, respectively. The separation/recovery of 10-DAP from paclitaxel was 74.1% in adsorbent treatment process under optimal conditions.

• Journal of the Korean Geotechnical Society
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• v.30 no.5
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• pp.5-15
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• 2014

Rockfill zone is a main part of the CFRD for safety and it is important to evaluate the status such as shear wave velocity profile of the rockfill zone. A surface wave method can be used to evaluate the rockfill zone but general surface wave method can have a difficulty to be applied for valuation of rockfill zone because of a stiff slope of dam and background noise in the field. In this research, HWAW method is applied to evaluate the shear wave velocity of rockfill zone. The field test of the proposed method is simple and fast and the HWAW method can determine the reliable shear wave velocity profile under severe noise field condition. To show feasibility of the proposed method, numerical simulation and field tests were performed. Through the numerical and field tests, the applicability of the proposed method was shown.

• Journal of the Korean Geotechnical Society
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• v.30 no.5
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• pp.17-24
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• 2014

This paper determines 1D shear wave velocity (Vs) distribution of rockfill zone of CFRD using Vs profile determined by the surface wave test. There exists uncertainty in the field test result because of a spatial variation of material property. The harmonic wavelet transform is used to evaluate the uncertainty of test result and generate random 1D Vs distributions which may exist in the rock fill zone. Through the statistical analysis of generated random Vs distributions, the representative 1D Vs distribution considering the uncertainty of test results is proposed for the rockfill zone of CFRD in Korea.

• The Journal of the Acoustical Society of Korea
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• v.39 no.3
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• pp.163-169
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• 2020

The asynchronous bistatic sonar needs to estimate direct blast arrival time at a receiver to localize targets, and therefore the direct blast arrival time estimation error could be added to target localization error in comparison with synchronous system. Direct blast especially appears as several peaks at the matched filter output by multipath, thus we compared the first peak detection technique and the maximum peak detection technique of those peaks for direct blast arrival time estimation through sea trial data. The test was performed in a shallow sea with bistatic sonar made up of spatially separated source and line array sensors. Line array sensors obtained the target signal which is generated from the echo repeater. As a result, the first peak detection technique is superior to maximum peak detection technique in direct blast arrival time estimation error. The result of this analysis will be used for further research of target tracking in the asynchronous bistatic sonar.

• Journal of the Korean GEO-environmental Society
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• v.7 no.1
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• pp.55-66
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• 2006

Laboratory tests have revealed that the liquefaction resistance of sands depends strongly upon the degree of saturation, which is expressed in terms of the pore pressure coefficient, B. The velocity of compression waves(i.e. P-waves), which have been known to be influenced largely by the degree of saturation and can be measured conveniently in the field, appears as an indicator of saturation. In this paper, the Stokoe type torsional shear(TS) testing equipment is modified to saturate the specimen and measure the velocities of P-wave and S-wave and pore pressure buildup. The velocities of P-wave and S-wave for Toyoura sand from Japan is measured and compared at the various B-value (degree of saturation) which are partially saturated to fully saturated conditions. Additionally, the variation of the pore water pressure induced during undrained TS tests at the various B-value is measured and analyzed.

• The Journal of Engineering Geology
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• v.23 no.4
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• pp.503-510
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• 2013

Shear wave velocity is widely used as an parameter for investigating subsurface characteristics and for obtaining the design parameters based on theoretical equations. This study seeks to estimate the coefficient of shear wave velocity in Busan clay via laboratory tests. Eight specimens were extracted at depths of 10, 12, 15, 20, 22, 25, 30, and 31 m. The specimens were subjected to the consolidation test to determine the relationship between effective stress and shear wave velocity. The relationship shows a non-linear trend and is similar to the results of a previous study. The coefficient shows constant coverage and a relationship between ${\alpha}$ and ${\beta}$ is suggested. The results demonstrate that this coefficient could be used as a reference value to determine engineering parameters based on the shear wave velocity.