• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.422-423
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• 2005

RF Micro switches is a miniature device or an array of integration devices and mechanical components and fabricated with Ie batch-processing techniques. RF Micro switches application area are in phased arrays and reconfigurable apertures for defence and telecommunication systems, switching network for satellite communication, and single-pole double throw switches for wireless application. Recently, RF Micro switches have been developed for the application to the milimeter wave system. RF Micro switches offer a substantilly higher performance than PIN diode or FET switches. In this paper, SPDT(single-pole-double-throw) switch are designed to use 10 GHz. Actuation voltage and displacement are simulated by tool.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.5
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• pp.627-634
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• 2006

We have proposed the methods how to control the slope of CMOS inverter's characteristic and how to shift it in y axis. We control the MOS transistor threshold voltage for these methods. By observing that two transistors are in saturation region at the center of the CMOS inverter's characteristic, we have presented how to make the characteristic for one pole neuron. The circuit level simulation is used for verifying the proposed method. PSpice(OrCAD Co.) is used for circuit level simulation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.652-655
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• 2004

RF MEMS is a miniature device or an array of integration devices and mechanical components and fabricated with If batch-processing techniques. RF MEMS application area are in phased arrays and reconfigurable apertures for defence and telecommunication systems, switching network for satellite communication, and single-pole double throw switches for wireless application. Recently, RF MEMS switches have been developed for the application to the milimeter wave system. RF MEMS switches offer a substantilly higher performance than PM diode or FET switches. In this paper, SPDT(single-pole-double-throw) switch are designed to use 10 GHz. Actuation voltage and displacement are simulated by tool. And stress and distribution are simulated.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.118-120
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• 2002

Voltage drop of low voltage distribution line is closely related with proper voltage regulation. It depends on the voltage drop of pole transformer, low voltage distribution line, and low voltage customer entrance line. Using above voltage drop factors, we proposes an estimation method of voltage drop in low voltage distribution line. Proposed method has been applied to a 22.9kV practical distribution system.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.2
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• pp.121-125
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• 2014

This paper presents a successful stand-alone pico-hydro generation system using a high-efficiency interior permanent-magnet (IPM) synchronous generator. A 1-kW 4-pole V-type IPM generator with low voltage regulation is used for laboratory test in stand-alone hydro energy conversion system. It has been found from experimental results that the constant output voltage is supplied stably by the proposed system under wide speed range.

• Journal of Welding and Joining
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• v.29 no.6
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• pp.71-76
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• 2011

Submerged arc welding method from both sides is generally applied to the welding of main panel manufacturing process during ship construction. The tandem SAW method is applied to improve the productivity. The various weld defects that occur during tandem SAW method are melt through, incomplete penetration, undercut and overlap etc. It could be thought that the reasons for these defects are mainly lack of prediction ability for penetration depth and deposited metal area. In this research, total 5 kinds of welding factors for experiment like current of lead pole, voltage of lead pole, current of trail pole, voltage of trail pole and welding speed are adopted. Weld tests are carried out for the analysis of variation effects of these factors on penetration depth and deposited metal area. Based on the test and analysis results, it is possible to obtain the prediction equation for the effect of these factors on the amount of deposited metal and penetration depth. As per the verification of the results by additional tests, it is confirmed that the prediction equation, include a error margin of ${\pm}2mm$ for penetration depth and ${\pm}10mm2$ for deposited metal area.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.134-136
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• 2005

The author present a modified multi-loop algorithm Including feedforward for controlling a 55kW stepdown chopper in the power supply of Maglev The gains of the control algorithm were selected based on pole locations formulated from a prototype Bessel transfer function model. The design incorporate tradeoffs in DC-to-DC converter hard-ware para-meters and pole locations. This perturvation is derived by subtracting the desired output voltage from the actual output voltage. The proportional and integral action stabilizes the system and minimizes output voltage error. In order to verify the validity of the proposed multi-loop controller, simulation study was tried using Matlab simulink.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.12
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• pp.1115-1120
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• 2007

This paper presents a novel mechanism of electro-spray micro-thruster featured by a nozzle with a conductive pole inside, referred to here as a pole type nozzle. And the effects of the pole type nozzle on the efficiency of the jetting are numerically and experimentally investigated. The electric voltage signal applied to the upper electrode plate, against the pole as the ground, allows a ejection of spray to take place. It is verified experimentally that the use of the pole type nozzle allows a stable and sustainable jetting mode of ejection for a wider range of applied voltages because it can concentrate the electric field more on the centre of the meniscus. According to results about size effect, experiments indicates that the proposed mechanism allows that operation of micro thruster at less than 500 volts through nanoscale nozzle.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.7
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• pp.339-350
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• 2002

Pole arcs, turn-on angle, and turn-off angle are major design factors, which affects Switched Reluctance Motor's torque performance. If these design factors are considered independently, the enhancement of SRM performance is restricted. Therefore, we need to consider pole arcs, turn-on angle and turn-off angle at the same time, when we design SR. In this paper, we analyze how these factors affect to torque ripple and average torque by using dynamic Finite Element Method(FEM) with derive circuit and present the good design results according to the various speeds. Especially, we formulate turn-on and turn-off angle from a voltage equation and present effective design range.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.24-26
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• 1999

In this paper, the conceptual design and FE analysis results of salient pole type alternator under no load condition are described. The designed alternator's rating is 180kW, 3-phase, 4pole, 380/220V, 0.8pf, 60Hz. The conceptual design is described by the process of designing the armature, field, and obtaining some of equivalent circuit parameters. The comparison of FE analysis to the designed results of alternator's output voltage value shows a good agreement.