• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.9
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• pp.477-483
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• 2013

A numerical analysis of solid-liquid phase change was performed on a heat transfer module which consisted of circulating water path (BRINE), heat transfer plate (HTP) and phase change material (PCM) layers, such as high temperature PCM (HPCM, $78{\sim}79^{\circ}C$) and low temperature PCM (LPCM, $28{\sim}29^{\circ}C$). There were five arrangements, consisting of BRINE, HTP, LPCM and HPCM layers in the heat transfer module. The time and heat transfer rate for melting/solidification was compared to their arrangements, against each other. As results, the numerical time without convection was longer than the experimental one for melting/solidification. Moreover, the melting/solidification with the BRINE I-LPCM-BRINE II-HPCM arrangement was faster(10 hours) than the others; HPCM-BRINE-LPCM, BRINE I-HPCM-LPCM-BRINE II one.

• 전기의세계
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• v.28 no.3
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• pp.65-71
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• 1979

This paper examines the reasonable winding arrangements of designing tapped winding capacitor motors to used in two voltage sources. The approach of this paper is based partly on a hybrid equivalent circuit of a single phase induction motor, together with an experimental method by sample machines. In results, the distribution of etra and main windings ia the stator is to be balanced in each magnetic pole and in order to have the same torque output characteristics for two different voltage sources, the extra/main winding ratio is to be adjusted. Experimental results obtaired with sample macines of about 1/8 hp output rating are used with analysis to predict the favorable winding conditions.

• Journal of Information Technology Applications and Management
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• v.24 no.3
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• pp.23-49
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• 2017

This paper is part of the dissertation for an MSc in Project Management and Innovation of Strathclyde Business School The research aims at understanding how IT-SMEs (Small and Medium-sized Enterprises in Information Technology Business) implement and use Flexible Work Arrangements and Flexible Working Hours (FWH/FWA) in their organisations. In-depth interview data was collected from managers and business owners of 31 companies whose needs for Work-Life Balance varied. Results show that many factors positively influence IT-SMEs to use FWH/FWA. For example, customers and partners working at different work-hours, traffic congestions between home and office, and the general stereotype of IT personnel. However, the results also found several concerning factors that may hamper the success of FWH/FWA implementation. They include the inadequacy of management skills in tracking, monitoring, and assessing employee's real performance, contextual factors for Thai IT-SMEs, i.e. conflict resolution culture, IT people's protocol of communication exchanges, and shortcoming of technology infrastructure. The findings also show that many companies that had used FWA eventually stopped. Thus, a four-phase cyclical framework called PLIC (Purpose-Limitation-Implementation-Consequence) has been developed as an approach to FWH/FWA implementation.

• Journal of IKEEE
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• v.24 no.2
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• pp.441-445
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• 2020

A Permanent Magnet Synchronous Motor (PMSM) for an electrical power steering system (EPS) is adopting various dual three-phase type stator windings to get the high fault tolerance capability when the motor runs at the failure condition. In this paper, we analyze the effects of stator winding arrangements on the characteristics such as torque and efficiency of the PMSM with leading and lagging current angle variations using finite element method. As a result, the most valuable design criteria are proposed to select stator winding method. Especially, we suggest the most appropriate winding method in terms of torque and efficiency, extending constant output area and decreasing noise and torque ripples.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.13-18
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• 2019

The domestic overhead transmission lines use a vertical configuration and reverse phase arrangement, but when there is a limitation in steel tower height because the transmission lines pass a height limit zone or special zone, an application of triangular arrangement is necessary, and a study on the optimal phase arrangement to minimize inductive interference for this is necessary. If conductor arrangement are changed, the action of electrostatic induction and electromagnetic induction becomes different from before changes, so the changed conductor arrangement should be reviewed in terms of inductive interference. So this paper presents an optimal phase arrangement to reduce inductive interference by calculating electrostatic induction and electromagnetic induction according to conductor arrangement.

• Journal of Korean Vacuum Science & Technology
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• v.2 no.1
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• pp.43-48
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• 1998

The effect of mcirostructure on the electrical properties of yttria stabilized zirconia (YSZ) was analyzed by modeling layer arrangements and mixed phase structure. The YSZ thin films were deposited by RF magnetron sputtering using 30mol% YSZ and 8 mol% YSZ targets with yttrium pellets on porous alumina substrates. The structure, composition and electricla properties of the YSZ films were investigated as functions of sputtering conditons and layer arrangements by XRD, TEM, XPS and acimpedance spectroscopy. The results showed that the triple palyered YSZ films had highermicrohardness, lower compressive stress state and higher ionic conductivity by one order than single and double layered YSZ films. However, sputtered YSZ films have low conductivity compared to YSZ pellets or doctor bladed YSZ thin plates. These results were probably due to the influence of insulating alumina substrates, impractical for most stacking geometries and inductance induced by relatively long platinum, lead wire on YSZ conductivity.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.4
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• pp.240-245
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• 2000

The self-field losses in a long multifilamentary Bi-2223/AgMgNi tape with varying transport current, voltage tap configurations, frequency and tape arrangements were investigated. Experimental results show that the measured losses are strongly dependent on voltage gap configurations but independent on tape arrangements. All voltage taps except the center tap are found to agree well with those predicted by Norris for an elliptical conductor. The self-field losses are purely hysteretic in nature in the range of applied frequencies for the transport currents below the critical current.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1379-1381
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• 1999

The unbalance current on the bundled conductors of the UHV overhead transmission line is one of the factors affected on power transmission system. It is varied by distance between of bundled conductors and of phase to phase, phase arrangement. In this paper, we calculated unbalance current on the bundled conductors by a variety of line arrangements and also calculated magnetic field at the circumference of the line fed with this unbalance current.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.371-373
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• 2002

High current density Bi-2223 tapes have recently become commercially available. The ac loss is an important issue in the design of high-T$_{c}$ superconducting power cables. In such complicated devices, special caution is required in the placing of voltage leads for measuring the in-phase voltage. In this paper, the ac losses for different contacts and arrangements of voltage leads have been experimentally investigated in a single layer model cable and discussed.d.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.210-212
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• 2003

High current density Bi-2223 tapes have recently become commercially available. The ac loss is an important issue in the design of high-T$_{c}$ superconducting power cables. In such complicated devices, special caution is required in the placing of voltage leads for measuring the in-phase voltage. In this paper, the ac losses for different contacts and arrangements of voltage leads have been experimentally investigated in a single layer model cable and discussed.d.