• Journal of the Korean institute of surface engineering
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• v.41 no.5
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• pp.205-213
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• 2008

A 3D particle code is developed to analyze electron behavior in a planar magnetron sputtering cathode either in balanced or unbalanced configuration. Three types of collisions are included; electron - neutral elastic, excitation to a metastable state and ionization. Flight path is calculated by a 4-th order Runge-Kutta method with a time step of 10 ps. Effects of electron starting position, magnetic field intensity and configuration were analyzed. For a more efficient and accurate modeling, multithreading technique is considered for multicore CPU computers. Under an assumption of cold ion approach, target erosion profiles are predicted for a flat target surface.

• International Journal of Control, Automation, and Systems
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• v.5 no.6
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• pp.621-629
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• 2007

In the adaptive fuzzy control field for affine nonlinear systems, there are two basic configurations: direct and indirect. It is well known that the direct configuration needs more restrictions on the control gain than the indirect configuration. In general, these restrictions are difficult to check in practice where mathematical models of plant are not available. In this paper, using a simple extension of the universal approximation theorem, we show that the only required constraint on the control gain is that its sign is known. The Lyapunov synthesis approach is used to guarantee the stability and convergence of the closed loop system. Finally, examples of an inverted pendulum and a magnet levitation system demonstrate the theoretical results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.83-88
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• 1993

Recently, the analysis of microcutting with submicrometer depth of cut is tried to get a more high quality surface product, but to get a valuable result another method instead of conventional finite element method must be considered because finite elment method is impossible for a very small focused region and mesh size. As the altermative method, Molecular Dynamics or Statics is suggested and acceoted in the field of microcutting, indentation and crack propagation. In this paper using Molecuar Dynamics simulation, the phenomena of microcutting with subnanometer chip thickness is studied and the cutting mechanism for tool edge configuration is evaluated. As the result of simulation the atomistic chip formation is achieved.

• 한국가시화정보학회:학술대회논문집
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• 2005.12a
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• pp.50-53
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• 2005

The turbulent flow around a sphere was investigated in a streamwise meridian plane using two experimental techniques: smoke-wire flow visualization in wind tunnel at Re=5,300 and PIV measurements in a circulating water channel at Re=7,400. The smoke-wire visualization shows flow separation points near an azimuthal angle of $90^{\circ}$, recirculating flow, transition from laminar to turbulent shear layer, evolving vortex roll-up and fully turbulent eddies in the sphere wake. In addition, the mean flow pattern extracted by particle tracing method in water tunnel at Re= 14,500 reveals two distinct comparable toroidal(not closed) vortices in the recirculation region. The mean velocity field measured using a PIV technique demonstrates the detailed wake configuration of close symmetric recirculation and near-wake configuration with two toroidal vortices, reversed velocity zone and vorticity contours.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.5
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• pp.630-634
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• 2016

We report the computer aided design results for a GaSb/InAs broken-gap gate all around nanowire tunneling FET (TFET). In designing, the semi-empirical tight-binding (TB) method using $sp3d5s^*$ is used as band structure model to produce the bulk properties. The calculated band structure is cooperated with open boundary conditions (OBCs) and a three-dimensional $Schr{\ddot{o}}dinger$-Poisson solver to execute quantum transport simulators. We find an device configuration for the operation voltage of 0.3 V which exhibit desired low sub-threshold swing (< 60 mV/dec) by adopting receded gate configuration while maintaining the high current characteristic ($I_{ON}$ > $100 {\mu}A/{\mu}m$) that broken-gap TFETs normally have.

• Journal of the Korean Electrochemical Society
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• v.20 no.1
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• pp.18-25
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• 2017

In this review, I have summarized the solar water splitting research based on the organic metal halide perovskite material, which has recently been spotlighted worldwide. Significantly, to date, recent reports have been categorized as photovoltaic-electrolyzer configuration and integrated photoelectrolysis. Research in this field is still in its early stages, and it is necessary to develop an effective protection film and manufacture a high-voltage tandem cell in the future.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1327-1331
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• 1990

A new dual loop controller using color LCD bar graphs with LED back lights has been developed. An optional memory card is used to load or save the controller configuration, which may be a preprogrammed standard package or a user-programmed configuration, in addition to the built-in functions ready for user selection. The bar-graph display is selectable for single-loop or dual-loop use. A high grade of self-tuning functions using a modeling technique is built-in as standard. The controller can accommodate optional plug-in modules for thermocouples, communication, etc. All the options are fully field upgradable.

• Journal of Electrical Engineering and Technology
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• v.6 no.3
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• pp.328-333
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• 2011

A Distribution Automation System (DAS) is operated by monitoring and control of the field statesusing Feeder Remote Terminal Units (FRTUs) installed together withautomatic switches.An optimal placement of automatic switchescan enhanceefficiencyof the operation and restoration, and improve the power supply reliability ofa DAS.This paper proposes an algorithm to decide the optimal placement of automatic switches ina DAS.The proposed algorithm was developed ona DAS witha six sections and three links configuration. The proposed algorithm was provided inaneight-feeder power distribution system.

• Proceedings of the Technology Innovation Conference
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• 1999.06a
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• pp.226-244
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• 1999

Very closely related to technologies, patents, standards, and licensing interact with them, cores of technology innovation, as the technology diffusion media for technology innovation. Todays it is usually impressed that no one can face to international technology competetion environment without the strategy of patent, standardization, and licensing. In this paper, the whole configuration of technology innovation is represented including the patent, standard, licensing as these media, their basic characteristics and how they roles as technology diffusion media interacting with the technology, core of the technology innovation configuration are analyzed, and some related practical cases to be understood as the applications of these three media for technology innovation are also explained : such as IMT-2000 and CDMA technology which have been international issues currently involved in patents and standardization together, the advent of Linux operating system being the new event in the field of computer technology. Finally this paper intends to have the implicated meanings needed for national policy improvement, through appreciating the importance and the mechanism of roles of three media factors for technology innovation.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.89.2-89.2
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• 2011

The geometry of an MC (magnetic cloud) in the interplanetary space can be estimated by the magnetic flux rope model. But the single point observation in the interplanetary space near the Earth is scanty to comprehend the global configuration of MC because the MC is considered a huge loop extending from the Sun with both legs rooted on the Sun. If the MC is observed at two different locations sufficiently far away from each other, it may provide the global configuration of the MC. In this study, we model the MC which is observed two different locations using a simple straight cylinder model. The MC model fit parameters are the flux rope axis orientation (${\Theta}$, ${\phi}$), the intensity of the magnetic field at the flux rope axis ($B_0$), the radius of the MC ($R_0$), and the impact parameter (p), etc. With the MC model fit parameters we look into the difference between two observed MC geometries and also calculate the magnetic flux and helicity of the MC.