• Journal of the Korea Safety Management & Science
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• v.9 no.5
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• pp.111-116
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• 2007

The objective of this paper is to calculate the minimum scale of management for transportation business in order to achieve a form of enterprise. In this study the tracking minimum scale of business is the minimum number of operating trucks. Transportation companies should ensure the number of trucks for a type of business model rather than a means of livelihood model. The method to calculate the minimum number of trucks for the transportation business model can use an approach of either the qualitative and the quantitative technique. This study chooses the quantitative technique to calculate the minimum number of trucks through the analysis of break-even point.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.9
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• pp.409-416
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• 2001

This paper deals with the design of delay-dependent $H_{\infty}$ control for time-delayed linear systems. We propose the two different model transformations to handle efficiently the time delay and derive conditions linear matrix inequalities (LMI's) of which are dependent on the size of time-delay and its time-derivative. The $H_{\infty}$ controller is obtained by checking the feasibility of these LMI's. Finally, we show the usefulness and applicability of our results by an example.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.4
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• pp.694-699
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• 2011

This paper compares the performance of lightning shielding analysis methods using the seven striking distance formulae in substation. For comparison, we evaluate the number of expected strikes and exposed area using WinIGS Software. Seven striking distance formulae are compared using the electrogeometric model analysis and the rolling sphere method. Based on the electrogeometric model analysis, the risk of shielding failure in either the whole substation or parts of it is determined. According to the simulation results, one can justify whether the substation satisfies the criterion of shielding design. In particular, according to the rolling sphere method, the exposed areas in substation determine the location of the additional shielding poles or shield wires. Therefore, the installation of the additional shielding poles and shield wires in substation was accepted by shield design at the phase conductors exposed in the larger area.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.90-90
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• 2011

Long-term nonstationary oscillations (NSOs) are commonly observed in hydrological and climatological data series such as low-frequency climate oscillation indices and precipitation dataset. In this work, we present a stochastic model that captures NSOs within a given variable. The model employs a data-adaptive decomposition method named empirical mode decomposition (EMD). Irregular oscillatory processes in a given variable can be extracted into a finite number of intrinsic mode functions with the EMD approach. A unique data-adaptive algorithm is proposed in the present paper in order to study the future evolution of the NSO components extracted from EMD.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.73-77
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• 2019

Isothermal (vapor + liquid) equilibrium data measurements were undertaken for the binary mixtures of (propylene oxide + 1-pentanol) system at three different temperatures (303.15, 318.15, and 333.15) K. The Peng-Robinson-Stryjek-Vera equation of state (PRSV EOS) was used to correlate the experimental data. The van der Waals one-fluid mixing rule was used for the vapor phase and the Wong-Sandler mixing rule, which incorporates the non-random two liquid (NRTL) model, the universal quasi-chemical (UNIQUAC) model and the Wilson model, was used for the liquid phase. The experimental data were in good agreement with the correlation results.

• Structural Engineering and Mechanics
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• v.76 no.5
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• pp.643-651
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• 2020

Generally, it is necessary to perform transient structural analysis in order to verify and improve the seismic performance of high-rise buildings and bridges against earthquake loads. In this paper, we propose the model order reduction (MOR) method using the Krylov vectors to perform seismic analysis for linear and elastic systems in an efficient way. We then compared the proposed method with the mode superposition method (MSM) by using the limited numbers of modal vectors (or eigenvectors) calculated from the modal analysis. In the calculation, the data of the El Centro earthquake in 1940 were adopted for the seismic loading in the transient analysis. The numerical accuracy and efficiency of the two methods were compared in detail in the case of a simplified high-rise building.

• Science of Emotion and Sensibility
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• v.16 no.4
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• pp.469-480
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• 2013

In this paper, we propose new method to reduce variance and express mixed feelings in Russell's emotional dimension(A Circumplex model). A Circumplex model shows mean and variance of emotions(joy, sad, happy, enjoy et. al.) in PAD(Pleasure, Arousal, Dominace, et. al.) dimension using self-diagnostic method(SAM: Self-Assessment-Manikin). But other researchers consistently insisted that Russell's model had two problems. First, data(emotional words) gathered by Russell's method have too big variance. So, it is difficult to separate valid value. Second, Russell's model can not properly represent mixed feelings because it has structural problem(It has a single Pleasure dimension). In order to solve these problems, we change survey methods, so that we reduce value of variance. And then we conduct survey(which can induce mixed feelings) to prove Positive/Negative(Pleasure) part in emotion and confirm that Russell's model can be used to express mixed feelings. Using this method, we can obtain high reliability and accuracy of data and Russell's model can be applied in many other fields such as bio-signal, mixed feelings, realistic broadcasting, et. al.

• Archives of Pharmacal Research
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• v.19 no.4
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• pp.302-306
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• 1996

The $^1H- and^{13}C-NMR$ spectra of alaternin, aurantio-obtusin, chryso-obtusin, obtusin and 2-glucosyl obtusifolin isolated from the seeds of Cassia tora have been assigned based on HMBC, long-range HETCOR, fully $^1H-coupled {13}^C-NMR$, deuterium isotope experiment, and by comparison with the model compounds.

• Proceedings of the Korea Water Resources Association Conference
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• 1994.02a
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• pp.405-409
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• 1994

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.525-528
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• 2011

Noise emitted by driving cars affects our daily life, penetrating wherever man lives or works. There are three types of possible sound emitting processes that are aerodynamic sources, air pumping and tire vibration. In this paper, a theoretical model has been studied to describe the sound radiation by the surface vibration of running tires and experimental verification has been conducted to evaluate sound radiation characteristic due to tire vibration.