• Journal of the Korean Society of Safety
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• v.8 no.1
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• pp.47-53
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• 1993

Residual Deformation Analysis(RDA) is a new method for ratings of the continuous bridges. The RDA makes it possible to expand the inelastic steel girder bridge design method set forth in the American Association of State Highway Officals'(AASHTO) Guide Specifications for Alternate Load Factor Design Procedures for Steel Beam Bridges Using Braced Compact Sections(1986) into an inelastic rating method. It is a method to assess the residual moments and deformations that are set up in a beam that has been loaded into the post-elastic range This method combines classical elastic conjugate beam theory with linear moment-rotation relationships for midspan inelastic positive moment. The limit state is inelastic serviceability limit. which is defined as the ratio of the span to midspan inelastic deflection(C=L/D).

• Journal of Korean Society of Steel Construction
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• v.18 no.1
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• pp.101-111
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• 2006

The SCP girder, which compensates for the shortcomings of conventional girders through the effective composition of concrete, steel, and PS tendon, has recently been developed and applied on real bridges. Developed as a simple-support type, it may be applied on simple-support and continuous bridges by connecting the simple-support SCP girders to the interior supports. A continuous SCP girder, which has structural and cost advantages over the simple-support SCP girder, is proposed in this study. Likewise proposed herein is a new method of constructing a continuous SCP girder, using segments of the girder sequentially. A two-span, half-scale specimen was designed and constructed to verify the propriety of the continuous SCP girder bridge. A static load test was also carried out, using this specimen, to examine the behavior of the continuous SCP girder. Based on the results of the study, it is expected that the continuous bridge that uses the continuous SCP girder can guarantee the structural safety of the simple-support SCP girder.

• The Journal of the Korea Contents Association
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• v.15 no.8
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• pp.564-578
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• 2015

The present study is aimed to investigate antecedents(person-job fit, human capital investment) and outcome variable(subjective career success) of continuous-related career learning, and to demonstrate mediating effects of continuous-related career learning. The data which was applied to analysis was collected from 241 office workers who have worked for automobile company in Ulsan and public companies in Jeju and applied temporal separation of measurement as an alternative for common method bias. The results are as follows. First, person-job fit, human capital investment affected to career-related continuous learning positively. Second, the impacts of career-related continuous learning to subjective career success was positively significant. Third, the mediating effects by career-related continuous learning demonstrated statistically significant in the links between antecedents-outcome variables as partial mediation. Implications of this study contribute to expand research area of continuous-related career learning with regard to job and organizational variables, and to facilitate of research interests on subjective career success. In addition, the mechanism of career advance was empirically proved by continuous-related career learning.

• Journal of KIISE:Databases
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• v.34 no.1
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• pp.70-83
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• 2007

Most of works for skyline queries have focused on static data objects. With the advance in mobile applications, however, the need of continuous skyline queries for moving objects has been increasing. To process continuous skyline queries, the 4-phased decision method of skyline regions has been proposed recently. However, it is not feasible for a large number of data because of the high cost of computing skyline regions. To solve this problem, this paper first provides a theoretical analysis of the 4-phased decision method. Then we propose a progressive decision method of skyline regions for the 4-phased decision method, which consists of a distance-based pruning and an extent shrinking of region decision lines. The proposed method can efficiently reduce the cost of the decision of skyline region in the 4-phased decision method. This paper also presents the experimental results to show the effectiveness of the proposed method.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.146-152
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• 2020

This study was initiated to develop an effective inspection method to detect defects such as corrosion in closed-cell steel members in steel-box girder bridges. The ultrasonic velocity method among various non-destructive method was selected as a rapid and effective method to derive the average propagation velocity in the medium by using the ultrasonic wave velocity method for specimens of different thickness. The regression analysis was performed based on the experimental results, and the results was interpolated to evaluate the prediction accuracy. If the material properties are identical, this ultrasonic velocity method can predict the thickness using the averaged transmitted velocity. In addition, a continuous scanning method moving at 200 mm/s was tested for scanning a wide area of a bridge. The results exhibited that the continuous scanning method was able to effectively scan the different thickness of a bridge.

• Journal of the Korean earth science society
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• v.28 no.7
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• pp.903-913
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• 2007

In this study, the researchers compared the S-wave velocity structures obtained by two kinds of dispersion curves: phase and group dispersions from a tidal flat located in the SW coast of the Korean peninsula. The ${\tau}-p$ stacking method was used for the phase velocity and two different methods (multiple filtering technique: MFT and continuous wavelet transform: CWT) for the phase velocity. It was difficult to separate higher modes from the fundamental mode phase velocities using the ${\tau}-p$ method, whereas the separation of different modes of group velocity were easily achieved by both MFT and CWT. Of the two methods, CWT was found to be more efficient than MFT. The spatial resolutions for the inversion results of the fundamental mode for both phase and group velocities were good for only a very shallow depth of ${\sim}1.5m$. On the other hand, the spatial resolutions were good up to ${\sim}4m$ when both the fundamental and the 1st higher mode poop velocities obtained by CWT were used for S-wave inversion. This implies that the 1st higher mode Rayleigh waves contain more information on the S-wave velocity in deeper subsurface. The researchers applied the CWT method to obtain the fundamental and the 1st higher mode poop velocities of the S-wave velocity structure of a tidal flat located in SW coast of the Korean peninsula. Thea the S-wave velocity structures were compared with the borehole description of the study area.

• Korean Journal of Food Science and Technology
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• v.51 no.2
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• pp.103-108
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• 2019

This study was conducted to select the optimal extraction method of codonopsis lanceolata saponin. To investigate the lancemasides content depending on each extraction method, various extractions were performed: reflux (methanol and butanol), hot water, as well as ultrasonic bath (40 kHz; continuous irradiation/interval irradiation) and ultrasonicator (20 kHz) extractions. From the result, the overall lancemasides content were the highest in ultrasonic bath (MeOH; continuous irradiation) extraction, followed by ultrasonic bath (water; continuous irradiation)>ultrasonic bath (MeOH; interval irradiation)>ultrasonicator (MeOH)>hot water>MeOH reflux>BuOH reflux extractions in that order. Sample drying method prior to ultrasonic bath extraction was more effective shade drying than freeze drying. Effective duration and temperature of extraction was 2 hr at $64^{\circ}C$. And ingredient change diverted from aster saponin Hb to lancemasides was identified by extraction condition such as extraction time and temperature.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.3
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• pp.221-229
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• 2004

The Continuous Wavelets Transform project signal f(t) to "Time-scale"plan utilizing the time varied function which called "wavelets". This Transformation permit to analyze scale time dependence of signal f(t) thus the local or global scale properties can be extracted. Moreover, the signal f(t) can be reconstructed stably by utilizing the Inverse Continuous Wavelets Transform. In this paper, the EEG signal is analyzed by wavelets coherence method and the De-noising procedure is represented.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.7
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• pp.484-489
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• 1988

Sufficient conditions concerning the perturbation region of system parameters, which guarantee the asymptotic stability of linear time- varying systems, are presented. These conditions are obtained by Lyapunov function approach for continuous-time and discrete-time systems. Also, a computational algorithm using nonlinear programming is proposed for finding the maximum perturbation region which satisfies the sufficient condition for the continuous-time systems. The technique of finding the solution for the continuous-time systems can also be applied to the discrete-time systems. In the continuous-time case, it is shown by an example that the method proposed in this paper yields much larger perturbation region of parameters than other previously reported results. An example of the perturbation region of system paramters for the discrete-time system is also given.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1910-1914
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• 1991

In the continuous casting process, mold level fluctuation Is the major cause of the surface and sub-surface defects. In the No.3 bloom continuous caster at Kobe Works, we ensured that the major cause of mold level fluctuation was mechanical hysteresis which existed in the driving system of mold level control. Moreover, we found out that it was possible to greatly Improve the stability of mold level by estimating this mechanical hysteresis and compensating It on-line. As a result of applying a new level control system based on this method, we got accurate control over good stability.