• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.437-442
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• 2005

This paper deals with the measurement and analysis of radio characteristic of 424 MHz for using the automation of transmission and supply of electric power, ana automatic meter reading(AMR). Normally radio propagation characteristic is the base of system design, performance evaluation and choice of position of the base station in wireless communication. It is the most accurate way to design a base station through practical measurements, but it costs much time, money and engineers. So, we developed 424 MHz short range wave propagation model for AMR service.

• 전력전자학회논문지
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• 제11권3호
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• pp.284-291
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• 2006

최근 가전 및 자동차시스템의 전동화에 따라 고효율 전동기에 대한 관심이 고조되고 있다. 따라서 본 논문에서는 고속구동시 고효율구동이 가능한 코어없는 AFPM전동기의 운전특성에 대해서 기술하고 설계관점에서의 그 전기적 특징에 대해서 논의한다. 특히 전동기 특성에 큰 영향을 미치는 역기전력 및 공극에서의 자계특성을 보이고 또한 인덕턴스특성에 따른 제어특성에 대해서도 시뮬레이션 및 실험을 통해 고찰한다. 회로망법을 기초로한 전동기설계결과와 출력특성실험결과의 비교검토를 통해 토크-속도 및 효율운전특성을 확인하였으며 제어특성을 확인한다. 아울러 코어가 없어짐에 따라 생길 수 있는 진동 및 소음특성에 대해서도 평가한다.

• 전자공학회논문지A
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• 제33A권7호
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• pp.99-110
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• 1996

In this paper, the analysis o fthe electric field distribution for TEM cell which is matched iwth 50 is performed, and the relations of variables for characteristic impedance are derived. Quasi-static approximations are used to calculate the fiedl strength of the internal field of TEM cell. The results of the improved method for analysis of the electric field is compared with that of R.J. Spigel. and the improved method for characteristic impedance and the results of numerical analysis are shown.

• Journal of Advanced Marine Engineering and Technology
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• 제32권8호
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• pp.1296-1302
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• 2008

This paper deals with modeling and dynamic characteristic analysis of a large-powered LNG electric ship propulsion system. Basically, we perform to verify the adequacy of system modeling on the sea going mode and LNG unloading mode based on load flow analysis. And then, we observe the dynamic characteristic of system to perform motor starting analysis and transient stability analysis. Particularly, this paper examine analysis results in comparison with the IEEE standard 141 and the class rule. Hence, this paper has evaluated stability of the electric ship propulsion system at static and dynamic conditions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.116-118
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• 2001

This paper deals with characteristic analysis of a slotless PM linear motor using analytical method. In order to calculate voltage equations, back-EMF waveform and winding inductance are caculated by PM's magnetic field and winding's magnetic field respectively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권3호
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• pp.1030-1050
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• 2021

The edges with "bridge characteristic" play the role of connecting the communication between regions in power optical cable network. To solve the problem of mining edges with "bridge characteristic" in provincial power optical cable network, the complex power optical cable network model is constructed. Firstly, to measure the generated potential energy of all nodes in n-level neighborhood local structure for one edge, the n-level neighborhood local structure topological potential is designed. And the minimum connected chain attenuation is designed to measure the attenuation degree caused by substituted edges. On the basis of that, the minimum connected chain attenuation topological potential based measurement is designed. By using the designed measurement, a bridge-edges mining algorithm is proposed to mine edges with "bridge characteristic". The experiments are conducted on the physical topology of the power optical cable network in Jilin Province. Compared with that of other three typical methods, the network efficiency and connectivity of the proposed method are decreased by 3.58% and 28.79% on average respectively. And the proposed method can not only mine optical cable connection with typical "bridge characteristic" but also can mine optical cables without obvious characteristics of city or voltage, but it have "bridge characteristic" in the topology structure.

• Journal of Acupuncture Research
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• 제17권3호
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• pp.25-35
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• 2000

Objectives : The characteristic of meridian system has been similar to this of electric potentials in human body. Therefore to measure the electric potentials in healthy volunteers and patients, and to find out the characteristic of meridian system and also to do that of differences between them. Methods : Twenty-nine healthy volunteers, thirty patients diagnosed as a cerebral infarction and wind-syndrome caused by hyperactivity of the liver-yang(肝陽化風) were examined into electric potential of well(井穴) and sea(合穴) points in branches of the twelve meridians by physiograph. Results : Measurements were analyzed by factor analysis, then we obtained that both the right and the left electric potential of well and sea points in branches of the twelves meridians in healthy volunteers were divided into two factors, hand meridian and foot meridian. Where as the left electric potential of those in patients with cerebral infarction were divided into three factors, one is foot meridian, another is hand meridian with the exception of large intestine meridian, and the other is large intestine meridian and also the right electric potential were divided into three factors, foot meridian, hand meridian with the exception of large intestine and lung meridian, and large intestine and lung meridian. Conclusions : In the results, healthy volunteers differ from patients in characteristic of electrical potentials, which means that we are able to catch the characteristic of meridian system by electrical potentials of well and sea points.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2003년도 학술대회지
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• pp.229-234
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• 2003

As electrorheological fluid(ER fluid) has a characteristic that apparent viscosity varies when electric field applied, so rheological characteristic(yield stress & viscosity) changes in proportion to the electric field applied and the response time is very short within a few miliseconds . In case of using ER fluid for journal bearing as lubricant, it is estimated that it's possible to realize very effective journal bearing system that is not complicate and has a very quick response time. It is necessary to examine the influence of rheological characteristic that varies with electric field applied on bearing characteristic to apply ER fluid to journal bearing, however there are few studies for about that. As for the journal bearing, it comes under high shear flow mode that has shear rate range of $10^3\~10^4s^{-1}$ because rotational speed is very high and clearance is small. But most of the studies for about ER fluid issued until now is about the range of $10\~10^2s^{-1}$. So, there are a lot of difficulties to understand the characteristic offish shear flow mode and furthermore it is restricted to make an experiment for about the characteristic of ER fluid because of the limitation of experimental equipment. The equipment was prepared to make an experiment lot high shear flow mode that has the range of $10^3\~10^4s^{-1}$ using ER fluid that is composed of silicon oil with dispersed particle of starch. Using the above system, the fluid characteristic of ER fluid was studied.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.9-11
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• 2001

This paper deals with design and characteristic analysis of a permanent magnet linear synchronous motor for magnetic levitation stage of semi-conductor manufacture machine. In order to improve the control performance by detent force minimization, skew and PM offset method are used.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 추계학술논문요약집
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• pp.127-128
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• 2018