• Bulletin of the Korean Chemical Society
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• v.17 no.8
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• pp.745-749
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• 1996

Fluorescence from the electronically excited thiophosgene (Cl2CS) in its first excited singlet state (S1) is efficiently quenched by collision. Rates of the collision-induced electronic relaxation were obtained for various vibrational levels in the S1 state by measuring the fluorescence lifetimes. We found that the relaxation process is strongly energy-dependent; the rate consistently increases by a factor of ~40 with the increase of vibrational energy from 0 to 1450 cm-1. Collision-induced intersystem crossing from the S1 to the first triplet state (T1) is attributed to the major process responsible for the electronic relaxation.

• Journal of Electrical Engineering and information Science
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• v.1 no.2
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• pp.33-38
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• 1996

In this paper, we present a robust H\ulcorner control design method for parameter uncertain systems that have delay in both state and control input. Through a certain algebraic Riccati inequality approach, a state feedback controller is obtained. The proposed state feedback controller stabilizes parameter uncertain delay systems and guarantees disturbance attenuation within a prescribed level. An illustrative example is given to demonstrate the results of the proposed method.

• International Journal of Automotive Technology
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• v.8 no.3
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• pp.361-373
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• 2007

In previous work, an approach based on maximizing the efficiency of an internal combustion engine while ignoring the power conversion efficiency of other powertrain components, such as the electric motor and power battery or ultracapacitor, was implemented in the steady-state optimization of an internal combustion engine for hybrid electric vehicles. In this paper, a novel control algorithm was developed and successfully justified as the basis for maximal power conversion efficiency of overall powertrain components. Results indicated that fuel economy improvement by 3.9% compared with the conventional control algorithm under China urban transient-state driving-cycle conditions. In addition, using the view of the novel control algorithm, maximal power generation of the electric motor can be chosen.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.172-173
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• 2005

The electronic state of ZnO doped with Y was calculated using the density functional theory. In this study, the program used for the calculation on theoretical structures of ZnO and doped ZnO was Vienna Ab-initio Simulation Package (VASP), which is a sort of pseudo potential method. The detail of electronic structure was obtained by the descrite variational $X\alpha$ (DV-$X\alpha$) method, which is a sort of molecular orbital full potential method. The optimized crystal structures obtained by calculations were compared to the measured structure. The density of state and energy levels of dopant elements was shown and discussed in association with optical properties.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.503-507
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• 2014

The on-state resistance ($R_{ON}$) instability of standard complementary metal-oxide-semiconductor (CMOS) antifuse cells has been observed for the first time by using acceleration factors: stress current and ambient temperature. If the program current is limited, the $R_{ON}$ increases as time passes during read operation.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.203-206
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• 2000

In this paper, we discuss an efficient steady-state analysis of reactance oscillators having multiple oscillations. Our oscillator is consisted of the Cauer or Foster reactance sub-circuit and a negative resistor such as tunnel diode. The reactance circuit has many resonance and antiresonance points on the frequency response curve. Such a circuit having the specified resonance and anti-resonance points can be easily synthesized with the fundamental circuit theory. In this case, the multiple oscillations may occur near at the anti-resonance points. We have developed a user friendly simulator for getting the exact steady state responses using the SPICE.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.879-880
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• 2006

The subject of this paper is to recognize the stable state of EEG using wavelet transform and power spectrum analysis. An alpha wave, showed in stable state, is dominant wave for a human EEG and a beta wave displayed excited state. We decomposed EEG signal into an alpha wave and a beta wave in the process of wavelet transform. And we calculated each power spectrum of EEG signal, an alpha wave and a beta wave using Fast Fourier Transform. We recognized the stable state by making a comparison between power spectrum ratios respectively.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.236-236
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• 2003

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.234-234
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• 2003

• Proceedings of the IEEK Conference
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• 2002.06e
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• pp.319-322
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• 2002

In this Paper, we suggested the Half-Bridge inverter for the automotive HID electronic ballast. electronic ballast for automotive HID lamp should be supplied by low-frequency square wave avoiding the acoustic resonance(11kHz ∼ 825kHz). When the HID lamp is hot state, the electronic ballast should supply the sufficient current for a few milli-second to the lamp at the re-strike ignition state. that is called take-over current. We have introduced the new take-over current control method that could have reduced the peak current and supplied the sufficient take-over current.