• Journal of Industrial Technology
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• v.25 no.B
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• pp.195-202
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• 2005

The rectifier characteristics and the quality of the input current worsens with the increase of unbalances or harmonics of the supply voltages. Rectifier input current harmonics interfere with proper power system operation, reduce rectifier power factor, and limit the power available from a given source. It is of importance to select appropriately the rectifier's output filter inductance to determine the rectifier input current waveform, the input current harmonics, and the power factor. This paper presents a quantitative analysis of single and three phase rectifier input current harmonics, total harmonic distortion, and power factor as a function of the output filter inductance under balanced and unbalanced conditions. Also, its performance under the supply voltage including harmonics be investigated. These results provide a reference for selecting reasonable rectifier's output filter inductance for given harmonics or power factor criterion.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.3
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• pp.67-73
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• 1998

In this paper, the BPFC(Boost Power Factor Collection) method is proposed to improve power factor and harmonic distortion. This method not only reduces the current and voltage distortion but also the physical size and brings expected high efficiency through current control methods. And the proposed BPFC has a distinct difference by control methods. The BPFC method proposed in this study has the characteristic of the high power factor and low harmonic distortion, and the control method using the peak current control and PWM average current control is comparative.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.153-156
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• 2004

An electric power efficiency of electrodeless fluorescent lamp has big relative property of gas in lamp, gas pressure, lamp formation, ingredients of magnetic substance and shape and action frequency etc. We used magnetic substance that open self examination material of electrodeless fluorescent lamp antenna. Ferrite that is used in this experiment was Mn-Zn type. We have examined resistance kind, impedance, Q-factor's frequency characteristic by ferrite. Impedance, resistance and capacitance did not show difference in start frequency 2.65 [MHz] but there was difference quantity. We could know Q-factor's difference according to material, and Q-factor's is important part of antenna design.

• Journal of Acupuncture Research
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• v.17 no.3
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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.

• Fashion & Textile Research Journal
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• v.11 no.2
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• pp.210-218
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• 2009

The Purpose of this study is to demonstrate Storytelling as an effective device for Fashion Design by establishing relationship between Fashion Design Process and Storytelling. Through researching a social background and a concept of storytelling, found that story used interactively is a powerful tool for attention, understanding and change in both individuals and communities. Analysed the elements and the structure of storytelling and Fashion Design Process, by researching preceding researches. Therefore, we proposed a new four elements -text factor, visual factor, audio factor and virtual factor- and four steps (1)exploring stories, (2)planning a story, (3)building the story, (4)do storytelling- of storytelling and four steps-(1)gathering and analysing informations, (2)building a concept, (3)planning and developing a design, (4)do evaluation and make decision- of fashion design process. Through comparative analysis, we found a closeness between two structures, a use of common factors and also found characteristics to be considered in each stage. In the first stage, we found text, visual and audio factor as common factors. In the second stage, we suggested text and visual factor as common factors and also suggested clarity, realism and probability as characteristics. In the third stage, we found text, visual and virtual factor and also found dynamism, immersion and continuity. In the last stage, we suggested text, visual, virtual and audio factor and also suggested presence and interactivity as characteristics.

• Proceedings of the IEEK Conference
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• 2002.06e
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• pp.311-314
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• 2002

In recent years, various power factor correction(PFC) circuits for the electronic ballasts have been proposed. In this paper, we have studied several passive PFC and compared with their characteristics, used in the electronic ballast for fluorescent. Especially, Improved Valley Fill Circuit (IVF) and the circuit IVF PFC combined with Charge Pumping Capacitors(CPCs) have been reaserched for High Power Factor. In conclusion, we have researched characteristics of Passive PFC and proposed the most effective PFC method.

• Progress in Superconductivity and Cryogenics
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• v.4 no.1
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• pp.66-72
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• 2002

This paper describes numerical modeling for thermal characteristic of vapor-cooled current leads under pulse operation. The transient thermal analysis considers the temperature difference between a helium gas (low and a copper lead and temperature dependent properties of helium gas, copper and stainless steel. This numerical modeling was compensated and validated by an experiment with commercially available 100 A vapor-cooled current leads. A proper overloading factor was suggested for the current leads under pulse operation through this modeling, which can significantly reduce heat input to a cryostat.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.663-667
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• 1998

This paper describes for reducing harmonic distortion on CO2 welding machine with nonlinear load characteristic using single-switch three-phase AC/DC converter. The low-order harmonic component amplitude of the phase current of single-switch three-phase discontinuous mode is calculated. Experimental results show that CO2 welding machine with single-switch three-phase AC/DC converter is effectively controlled with power factor correction for phase current during welding time.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1789-1791
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• 1999

In consideration of piezoelectric characteristic and Temperature stability, 3-element system dopped with NiO, $Cr_2O_3$ well-known as Hardner and Stabilizer whose primary element is PZT was eximanated its structure, piezoelectric characteristics, dopping with Nio, $Cr_2O_3$. We think that piezoelectric Characteristic is developed, remenent polarization and $E_c$ can developed in specimens by dopping with NiO, $Cr_2O_3$ additive. also, electromechanical quality factor largely showed tendency of decrement. According to dopping NiO, $Cr_2O_3$ more.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2205-2213
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• 1993

The characteristic test for gage factors of temperature self-compensated strain gages at cryogenic temperature is presented. By joining the international round robin test on electrical strain gages at cryogenic temperatures, the gage factors of three kinds of widely-used strain gages are obtained at the room temperature, the temperatures of liquid nitrogen and liquid helium. The calibration system which produce precise bending strain is by mechanical loading at cryogenic temperature. This paper also presents the creep characteristic of strain gages at maximum strain level.