• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1276-1281
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• 2007

This study examined the procedures and legal issues for introduction and current Salary-structures and methods for system introductions centered around Seoul Metro which is railway related public company along with the background on introducing Salary-peak system and national/international situations according to the changes in paradigms. Base on these, the study deduced presented plans for improving corporate competitiveness by the introduction of Salary-peak system such as target for applications and ages for Salary-peak and the rate of fall, plans for adjusting duties to present optimum plans according to the introduction of Seoul Metro Salary-peak System.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.136-140
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• 1999

Measurements of AE signals caused by partial discharges were performed by using an ultrasonic measurement technique to diagonise the electrical treeing deterioration in XLPE cable. We also examined the partial discharge magnitude and AE signals(peak-to-peak) with the increase of the deterioration time. From these results, it was found that AE signal due to partial discharge can be greatly detected at the peak value of positive polarities prior to the breakdown voltages, and the magnitude of AE signals was closely related to the current pulses by the increase of deterioration, and it appeared that AE signals(peak-to-peak) was proportional to partial discharge magnitude. Attenuation and time-delaying characteristics of ultrasonic signals propagated in various polymers sample by using ultrasonic oscillation and receiving systems are also reported as a basic data of ultrasonic measurements in XLPE cable.

• Journal of the Korean Ceramic Society
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• v.48 no.3
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• pp.205-210
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• 2011

The dependence of sulfur redox behavior and its diffusivity on temperature and composition was studied in mixed alkali silicate melts by means of square wave voltammetry (SWV) at different frequencies in a temperature range of $1000^{\circ}C$ to $1400^{\circ}C$. The voltammograms showed two reduction peaks at high frequency but only one peak at low frequency. Irrespective of $K_2O/(Na_2O+K_2O)$, each peak potential due to reduction of $S^{6+}$ to $S^{4+}$ and $S^{4+}$ to $S^0$ moved toward a negative direction with temperature decrease, and the peak current showed a strong dependence on frequency at a constant temperature. However, the compositional dependence of the peak potential showed an inconsistent behavior with an increase of $K_2O$. The mixed alkali effect was not observed in sulfur diffusion. This inconsistency of both peak potential and diffusion for compositional dependence may be derived from the strong volatilization of sulfur in melts.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1732-1734
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• 2001

The purpose of this experiment was to develope Triggered Vacuum Switch(TVS) and to improve understanding of the high current vacuum arc phenomena in the TVS. The TVS has an array of rods of alternate polarity in which a fixed gap spacing is maintained between the rods. The cross section of each rod has trapezoidal shape. Breakdown of the TVS produced high current vacuum arc plasma. A spectroscopic measurement was performed over 20 kA peak current in the center of electrodes, in the vicinity of cathode, and outside electrodes. The electrode material tested was Fe. Measured Fe spectrum range was from 200 nm to 900 nm. Measurement result showed that over 90 percent of the charge states were FeII and the others were FeI and FeIII. The electron temperature was determined from the relative line intensity ratio methode of FeII system by assuming the local thermal equilibrium(LTE). The electron temperature at the center of electrodes was measured as 1.5 eV at 26 kA peak current. The electron temperature varied with its peak current. Intensity of spectrums is the highest in the vicinity of the cathode. Further we will also present study result of the diode phenomena in the TVS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.717-722
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• 2016

In this paper, in order to support the peak current limiting function depending on the intensity of the fault current at the early stage of failure, a two magnetically coupled type superconducting fault current limiter (SFCL) is proposed, which includes high-Tc superconducting (HTSC) element 1, where the existing primary and secondary coils are connected to one iron core in parallel, and HTSC element 2, which is connected to the tertiary winding using an additional iron core. The results of the experiments in this study confirmed that the two magnetic coupling type SFCL having coil 1 and coil 2 connected in parallel using dual iron cores is capable of having only HTSC element 1 support the burden of the peak current when a failure occurs. The reason for this is that although HTSC element 1 was quenched and malfunctioned because the instantaneous factor of the initial fault current was large, the current flowing to coil 3 did not exceed the critical current, which would otherwise cause HTSC element 2 to be quenched and not function. In order to limit the peak current upon fault through the sequential HTSC elements, the design should allow it to have the same value as the low value of coil 1 while having coil 3 possess a higher self-inductance value than coil 2. In addition, a short-circuit simulation experiment was conducted to examine and validate the current limiting and recovery characteristics of the SFCL when the winding ratio between coil 1 and coil 2 was 0.25. Through the analysis of the short-circuit tests, the current limiting and recovery characteristics in the case of the additive polarity winding was confirmed to be superior to that of the subtractive polarity winding.

• 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.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.1
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• pp.72-79
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• 2013

In the paper, a pattern analysis to decide whether the 1st local peak power point near open circuit voltage is the global peak power point or not, in case that the voltage and current at the 1st local peak power point are in a specific range, for Maximum Power Point Tracking on the photo voltaic power conversion system. When a solar cell panel array is shaded partially, multi-local peak power points can occur. That makes it hard to search the global peak power point. Through Tableau analysis using by piecewise linear solar cell model, V-I characteristic of a solar cell panel array circuit when partial shading problem happens, is simulated. The global peak power and the local peak power points is confirmed by simulations. Voltage and current values and patterns of V-I characteristic are analyzed. The generating efficiency of the solar cell panel array is improved, when the solar cell panel array circuit is operated at the power point estimated by setting up specific range.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.1
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• pp.99-106
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• 2012

For CMOS technology of 65 nm and beyond, the gate leakage current can not be negligible anymore. In this paper, the impact of the gate leakage current in ring voltage-controlled oscillator (VCO) on phase-locked loop (PLL) is analyzed and modeled. A voltage -to-voltage (V-to-V) circuit is proposed to reduce the voltage ripple on $V_{ctrl}$ induced by the gate leakage current. The side effects induced by the V-to-V circuit are described and optimized either. The PLL design is based on a standard 65 nm CMOS technology with a 1.8 V power supply. Simulation results show that 97 % ripple voltage is smoothed at 216 MHz output frequency. The RMS and peak-to-peak jitter are 3 ps and 14.8 ps, respectively.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.2
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• pp.114-121
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• 2016

This paper is Instant space vector PWM(Pulse Width Modulation)power conversion devices in switching power semiconductors from my generation to losses and switching when the voltage surge and current surge of electronic noise(EMI: Electro Magnetic Interference / RFI: Radio Frequency Interference)to effectively minimize the power soft-switching power conversion circuit topologies of auxiliary resonant DC tank for the purpose of high performance realization of the electric power conversion system by the high-speed switching of a semiconductor device(AQRDCT simultaneously : an active auxiliary resonance using auxiliary Quasi-resonant DC tank)DC link snubber switch has adopted a three-phase voltage inverter. AQRDCL proposed in this paper can reduce the effective and current peak stress of the power semiconductors of the auxiliary resonant snubber circuit compared to the conventional active-resonant DC link snubber, it is not necessary to install the clamp switch of the auxiliary resonant DC link, DC the peak current and power loss of the bus line can be reduced.

• Journal of The Association for Neo Medicine
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• v.1 no.1
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• pp.115-122
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• 1996

A clinical observation was done on 98 cases performed neurometer diagnosis before Guibitang administration first, and rechecked neurometer diagnosis after Guibitang administration for 10 days. Electric current post administration was compared with ant administration. The following result were obtained. 1. A peak incidence was observed in 30-39 age group. 37 cases(37.8%) were in 30-39 age group. The ratio of male to female was 1:31.7. 2. Chief complaints were fatigue, menoxenia, indigestion, anorexia, constipation, headache, palpitation, insomnia etc. 3. The common result of neurometer point checking was that patients who had the pecularity of low electric current were much than patients who had the pecularity of high electric current. 4. By neurometer diagnosis a peak incidence was observed in gallbladder. Increment was also highest in gallbladder. Gallbladder has a function of psychomotility in oriental physiology. ?5. After Guibitang administration the increment of neurometer electric current was comparatively high in kidney, stomach, small intestine meridian. According to the above menthioned results I consider that Guibitang has the curative effects along the meridian selectively. and increases in function or preserves health within physycal limit.