• 전기전자학회논문지
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• 제15권1호
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• pp.96-103
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• 2011

본 논문에서는 발전기, 스위치보드, VFD, 추진전동기 등으로 구성된 전기추전선박의 전력 네트워크를 모델링하고, 전력조류해석과 단락전류해석을 통하여 계절별 선박 운용에 따른 전력시스템 특성 해석 및 단락사고 발생 시차단기의 용량을 선정한다. 이와 더불어 3.7MW급 유도전동기 및 영구자석형 동기전동기의 정성적, 정량적 비교 해석을 통해 전기선박 추진전동기로 적합성에 대해 추가 고찰한다.

• 한국자동차공학회논문집
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• 제20권1호
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• pp.53-60
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• 2012

As enforced by the regulation on the improving fuel efficiency and increased the demand on green technology, many interests are focused on electric vehicles and hybrid vehicles. Thus the technology development in electrification of vehicle operation system, including steering and braking field, is actively progressive. Especially electric power steering substitutes for hydraulic power steering rapidly in the market, which is more complex and bigger in packaging volume compared with electric power steering system. The core component in electric power steering system is a motor, which is required to be silent and powerful to guarantee required system performance. Brushless synchronous motors are widely used and many variations of the motors are introduced in the market, while the performance of each type is not well defined or studied for electric power steering system. In this paper, recent developments in brushless synchronous motor are reviewed and compared applying finite element analysis in electromagnetic field. As results, each characteristic of different types of brushless synchronous motors is compared and summarized for optimized selection in electric power steering system.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권6호
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• pp.403-410
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• 2000

This paper deals with a study to improve the performance of Moving Coil type Linear Oscillatory Actuator (MC-LOA) considering unbalanced magnetic circuit. MC-LOA has an unbalanced magnetic circuit due to its asymmetric structure. In this type of LOA, the airgap flux density tends to have different magnitude along mover's displacement and the current directions. The above property causes eccentric of displacement center and interferes with the proper oscillation of LOA. Therefore, this paper presents two models having the unbalanced magnetic circuit and the other balanced by the saturated core. In order to compare the characteristics between the two models, a characteristic analysis for both the basic model and the improved model is performed by their dynamic analysis composed of kinetic and electric equations and Finite Element Method (FEM). The propriety of the improved model is verified through the experimental results.

• 한국전기전자재료학회논문지
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• 제16권11호
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• pp.1008-1013
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• 2003

We have studied the effect of black matrix (BM) according to the dielectric anisotropy of liquid crystals (LCs) for a homogeneously aligned LC cell driven by fringe-electric field. The results show that for a LC with positive dielectric anisotropy (+LC) there is a large transmittance change when using a conductive BM, whereas the transmittance change is low for a LC with negative dielectric anisotropy (-LC). The conductive BM existing on top substrate produces vertical electric field, which makes the LC molecules be tilt upward from the substrate and have small twist angle for the +LC. However, for the -LC the conductive BM affects the LC distribution only slightly due to characteristic of the -LC orienting perpendicular to the field. Therefore, for the +LC the electro-optic characteristics are strongly dependent on conductivity of the BM on top substrate in a homogeneous liquid crystal cell driven by fringe-electric field.

• 마이크로전자및패키징학회지
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• 제27권4호
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• pp.77-81
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• 2020

Resistive RAM (ReRAM)은 전이금속 산화물의 저항변화 특성을 이용하는 차세대 비휘발 메모리로 전이금속산화물 내의 산소공공의 재분포를 통한 저항변화 특성을 이용한다. 따라서 저항변화 특성을 위해 전이금속산화물 내에는 일정량 이상의 산소공공이 요구되며 이를 위해서는 박막 형성 공정에서 산화 수를 조절할 수 있는 공정이 필요하다. 본 연구에서는 직접패턴이 가능한 photochemical metal organic deposition (PMOD) 공정을 사용하여 UV 노출에 의해 photochemical metal organic precursor의 ligand가 분해되는 과정에서 전기장을 인가하여 박막내의 산화 수를 조절하는 실험을 진행하였다. Electric field assisted PMOD (EFAPMOD) 법을 이용하여 FeOx 박막의 산화 수 조절이 가능함을 x-ray photoelectron spectroscopy (XPS) 분석과 I-V 측정을 통하여 확인하였으며, EFAPMOD 공정 중 인가하는 전압의 크기를 조절하여 박막의 산화 수를 조절할 수 있음을 확인하였다. 따라서 EFAPMOD 공정 중 인가전압의 크기를 이용하여 저항변화 특성에 적합한 적정한 산화수를 가지는 금속산화물 박막을 얻고 그 저항변화 특성을 조정할 수 있음을 확인하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1292-1296
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• 2004

This study is experimented results of running characteristics about electric locomotive. it executed to study a power quality in the substation of Honam electrification line and to promote knowledge, observation and management in electric rail-system. we measured to know the more exactly running characteristics that electric locomotive and electric substation at the same time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.540-541
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• 2005

• Korean Journal of Acupuncture
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• 제21권4호
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• pp.21-30
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• 2004

Objectives : Assuming that the characteristic of meridian system has been similar to this of electric potentials in human body and that measurements of electric potential at well(井穴) and sea(合穴) points in branches of the twelve meridians(WSBTM) will be representative of measurements of the twelve meridians, to measure the electric potentials of 13 patients with Arthroncus of Knee(슬안풍<膝眼風>, AK), to find out the characteristic of meridian system in patients with AK. Methods : Electric potentials of well and sea points in the meridians in twenty one patients with the pain in the lion diagnosed as AK were repeatedly measured by physiograph(PowerLab). Measurements of those electric potentials were analyzed by factor analysis. Results : Their electric potentials at the left and right side were factors which are different from each side. In the left side, Factor 1 included Small Intestine, Pericardium, Spleen, Kidney meridian, and Factor 2 included Heart, Tripple Energizer, Bladder, Liver meridian. Factor 3 included Large Intestine, Stomach, Gall bladder meridian, and Factor 4 included Lung meridian. In the right side, Factor 1 included Heart, Pericardium, Tripple Energizer, Spleen, Bladder meridian and Factor 2 included Lung, Liver, Gall bladder meridian. Factor 3 included Small Intestine, Stomach, Kidney meridian and Factor 4 included Large Intestine Meridian. Conclusions : The electric potentials of AK differ from those of normal bodies as well as of bodies with other diseases-shoulder lesions, waist lesions, Lumbago due to Strain and Contusion-. Thus electric potentials of well and sea points might be the representative meridian to show their characteristics.

• 자원환경지질
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• 제13권3호
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• pp.159-166
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• 1980

A model study was conducted for the investigation of apparent resistivity variation along with electric resistivity variation of host rock and dip variation of bed. Experiments were carried out for the cases of horizontal and dipping beds in a water tank by using Wenner and Schlumberger arrays and by changing salinity of water. The ratios of resistivity values of the bed to that of brine were 1 : 10, 1 : 50, 1 : 100 and 1 : 500. Natural coally-shale of $55cm{\times}35cm{\times}3.5cm$ was used as a bed for experimental model, and brine as a host rock. Equi-resistivity curves and characteristic curves were obtained for each case of the experiment. The equi-resistivity curve was drawn both on the cross section parallel to strike of bed and longitudinal section perpendicular to it. The characteristic curve was drawn on the cross section. In the case of dipping bed of different dips, the curves are parallel to the boundary of the bed in the upper part of the bed, and are inclined to the opposite direction with the same angle of the dip of bed in the lower part. We can deduce, from the equi-resistivity curves, the location, shape and dip of the bed. It is shown in the characteristic curves that when the ratio of resistivity value of bed to that of host rock increases, the slope of curves becomes steeper, location of low-resistivity zone lower, and the width of it narrower. The slope of curves also becomes steeper when dip of bed increases. We can deduce, from the characteristic curves, the ratio of resistivity values between adjacent beds. It was found out from the experiments that electric resistivity method could be applicable to prospecting for underground geology with an electric resistivity contrast of 1 : 10. This fact strongly suggests that distinction of coal from coally-shale could be possible in a certain field condition.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.447-448
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• 2007

Product development is consisting by trend that accommodate almost function digital cam in camera phone that can speak of Mobile appliance, and competition about number of elemental area of image sensor is consisting for market prior occupation between these. Propose in this research and small size camera phone self-focusing adjustment actuator that do city manufacture is similar with general storehouse pickup actuator drive way, but selected in cylindrical to reduce space that lens holder occupies because there is restriction loading of lens and space enemy. Target number of research established that execute drive displacement more than $600{\mu}m$ in 2.75V that is house voltage that is used in Mobile device that is general. Also, described about maximum transfer displacement characteristic, displacement response characteristic, hysteresis, response characteristic, smallest transfer step characteristic, actuator's drive characteristic that is manufactured to examination item of maximum consumption electric power by special quality estimation system that apply laser displacement sensor that produce itself to evaluate city manufactured actuator's special quality.