• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2006년도 춘계학술발표대회 논문집
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• pp.197-201
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• 2006

Following to current interior design that becoming more varied and composite, minimal tendency has also been changed. Furthermore, according to the lapse of time, minimalism, a space design, has been developed in a new look among such complex trends. Therefore, in this study, changes of tendency into a style of minimalism and characteristics thereof shown in interior design amid current of times were carefully reviewed, and local and foreign artists together with their works were investigated and analyzed having focused on the inclination of minimalism displayed in interiors of commercial spaces, especially before or after 2000s by dividing them into distinctive features in connection with space, material and type. It is thought that the interior space under the concept of minimalism will be changed and developed further in a variety of shapes to suit the environments in the current era getting rid of simple physical characteristics.

• Journal of Astronomy and Space Sciences
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• 제17권1호
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• pp.99-106
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• 2000

When a deployed probe is biased by a high positive potential during a space experiment, the payload is induced to a negative voltage in order to balance the total current in the whole system. The return currents are due to the responding ions and secondary electrons on the payload surface. In order to understand the current collection mechanism, the process was simulated with a combination of resistor, inductor, and capacitor in SPICE program which was equivalent to the background plasma sheath. The simulation results were compared with experimental results from SPEAR-3 (Space Power Experiment Aboard Rocket-3). The return current curve in the simulation was compatible to the experimental result, and the simulation helped to predict the transient plasma response to a high voltage during the plasma sheath formation.

• 전력전자학회논문지
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• 제23권5호
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• pp.336-344
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• 2018

This study proposes a new PWM method for leakage current reduction and neutral point (NP) current control in three-phase three-level converter employed in bipolar DC distribution systems. The proposed PWM method uses medium vectors only when there is no need to control the NP current. Thus, common mode voltages are held constant to realize zero leakage current. Some space vectors that produce low-frequency common mode voltages are employed to minimize leakage currents when the average NP current needs to be a positive or negative value. The proposed space vector PWM is implemented based on barycentric coordinate. The validity of the proposed PWM method is verified by simulations and experiments.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권1호
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• pp.39-39
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• 2004

It has been known that ring current particles can be lost through dayside MP(magnetopause). However, details of the loss mechanism of this process has not received much attention. In this study, we show that the solar wind dynamic pressure P$\sub$D/ can play a significant role in the dayside loss. In order to show that, we have first conducted superposed epoch analysis using 95 geomagnetic storm events selected from the period 1997 to 2002. (omitted)

• 전자공학회논문지A
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• 제32A권2호
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• pp.324-331
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• 1995

The leakage current characteristics of the low temperature processed LDD structure poly-Si TFT is analyzed. The excimer laser technology was applied to the recrystallization process of poly-Si film and the maximum processing temperature was retained under 600.deg.C. From the fabricated LDD space 0.3.mu.m to 3$\mu$m, the best on/off current ration could be obtained with the 1.3$\mu$m LDD space. And the threshold voltage did not increase more than 4V over 0.8$\mu$m LDD space. The characteristics of leakage current was compared to non-LDD structure TFT to analyze the mechanism of leakage current. Consequently, it could be concluded that the leakage current is strongly affected by the trap states as well as high electric field between gate and drain.

• 전기학회논문지
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• 제65권10호
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• pp.1639-1647
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• 2016

This paper deals with eddy current loss analysis of Slotless Double sided Cored type permanent magnet linear generator by using analytical method, space harmonic method. In order to calculate eddy current, this paper derives analytical solution by the Maxwell equation, magnetic vector potential, Faraday's law and a two-dimensional(2-D) cartesian coordinate system. First, we derived the armature reaction field distribution produced by armature wingding current. Second, by using derived armature reaction field solution, the analytical solution for eddy current density distribution are also obtained. Finally, the analytical solution for eddy current loss induced in permanent magnets(PMs) are derived by using equivalent, electrical resistance calculated from PMs volume and eddy current density distribution solution. The analytical result from space harmonic method are validated extensively by comparing with finite element method(FEM).

• 천문학회보
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• 제41권1호
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• pp.46.1-46.1
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• 2016

The formation process of a current sheet is important for solar flare from a viewpoint of a space weather prediction. We therefore derive the temporal development of the spatial and statistical distribution of electric current density distributed in a flare-producing active region to describe the formation of a current sheet. We derive time sequence distribution of electric current density by applying a nonlinear force-free approximation reconstruction to Active Region 12158 that produces an X1.6-class flare. The time sequence maps of photospheric vector magnetic field used for reconstruction are captured by a Helioseismic and Magnetic Imager (HMI) onboard Solar Dynamic Observatory (SDO) on 10th September, 2014. The spatial distribution of electric current density in NLFFF model well reproduce observed sigmoidal structure at the preflare phase, although a layer of high current density shrinks at the postflare phase. A double power-law profile of electric current density is found in statistical analysis. This may be expected to use an indicator of the occurrence of a solar flare.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.615-619
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• 1998

Active power filter is a kind of device used for compensating instantaneous reactive and harmonic current in three-phase circuits. An essential technology that determines the behavior of an active power filter is the method of detecting the distorted current. Using three-dimensional space vectors, this paper describes a simple method for detecting the distorted current without any coordinate transformation. The effectiveness of the novel method is verified by the theoretical analysis and simulation.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권2호
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• pp.23.1-23.1
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• 2009

Space physics is more than fifty years old and is going through middle age. Looking back and thinking about what has been learned during the past fifty years, one finds that progress was made at the expense of exactness. Past observations have been interpreted using theory with unreal assumptions. Theory and models must be testable, verifiable and consistent with observations. Current theory cannot explain many important observational results that are relevant for understanding how space plasmas work. This talk will examine the current model of space plasma and assess its capabilities. We will then discuss the required level of theory and models that should be developed to advance space physics to the next tier.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.36.4-37
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• 2008

KASI is planning a large telescope project to acquire 10% share of the GMT (Giant Magellan Telescope) extremely large telescope as one of national R&D project. By participating in GMT, we expect to provide the best environment for observational astronomers in Korea and give opportunity to upgrade the current research and instrumentation level to world-leading class. In this contribution, we will report the concept of the GMT project and Korean participation plan as well as the current status of fundraising activity.