• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.431-432
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• 2015

본 논문은 초고압 가스절연개폐장치의 메인 접점의 압점력에 따른 절연 특성에 대한 연구이다. 차단기 접점의 접촉이 잘 이루어지지 않는 현상이 발생하게 되면 접촉저항이 증가하여 차단기의 투입 및 개방 시에 전류에 의하여 접점에 손상이 발생한다. 그리고 차단기의 접점의 압점력이 커질수록 큰 조작력이 필요하므로 차단기의 동작에도 영향을 미치는 것은 많이 알려져 있다. 그러나 압점력과 절연 특성의 관계에 대한 연구가 미비하므로 이에 대한 연구가 필요하다. 본 연구는 초고압 가스절연개폐장치의 메인 접점의 압점력에 차이에 따른 전계를 해석하고, 고정측 접점의 쉴드 유무에 따른 절연 내력을 비교 및 분석하였다. 전계 해석 결과를 통해서 메인 접점의 압점력과 절연특성과 고정측 접점 쉴드의 영향을 비교함으로써 차단기 인터럽터 내부의 전계 분포를 확인하고, 전계 강도를 확인함으로 가스절연계폐장치의 적절한 절연내력 확보를 목적으로 한다.

• 한국안전학회지
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• 제29권2호
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• pp.12-17
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• 2014

This paper is aimed to analyze the characteristics of simultaneous voltage, current and temperature signals for poor connection on electrical connector. In order to attain this purpose, detected were the current and voltage signals on electric wire with series arc, named arc signals, and also monitored were the changes of RMS, instantaneous value of waveform in time domain and temperature value with video. Two states are made normal state over $5kgf{\cdot}cm$ and poor connections state below $0.5kgf{\cdot}cm$ by screw gage. In the voltage signal case, the voltage drop was increased with which the current was increased. In the current signal case, poor connections at the time interval 1~4A all showed "shoulder", as distinct difference from the normal state shown waveform pattern. In the temperature signal case, poor connections are twice at 1A and five times at 4A in the normal state. The temperature continues insulation of electrical wiring and connector can be carbonized. The results of this study will be effectively used in developing the preventive devices and system for electric fire by poor connections.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.225-229
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• 2011

The aluminum composite panel are widely used for the external materials of high rise building because of well insulation of heat and sound and improved Constructability. However, the polyethylene in main material of the aluminum composite panel shows weakness in thermal and fire resistances. For this reason, flame is spread more quickly when the fire break out. Therefore, the potentiality of fire spread to the exterior wall is high due to difficulty of early extinguishment and effect of external air. In this study, numerical investigation was performed by using FDS program for flame spread characteristics with various external air velocity and direction in ten-story building with the aluminum composite external materials. As a result, the flame spread velocity is 0.134m/s and it takes 224 seconds for flames to spread to the 10th floor without external air velocity. however, the flame spread velocity decreases 40% and it takes 348 seconds for flames to spread to the 10th floor when external air velocity is 2.5 m/s. and air direction is little effect compared to air velocity.

• 한국의류산업학회지
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• 제18권6호
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• pp.878-888
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• 2016

In this study, wool/nylon(50/50%) blend yarn and its fabrics for tra-biz(complex word of travel+business) garment were prepared, and its wear comfort characteristics were investigated through thermal manikin and human-body wearing experiment. In addition, tactile wearing performance from fabric mechanical properties and the dimensional stability and the pilling of the fabric specimen during wearing and dry-cleaning were measured and compared with those of wool 100% fabric specimen. Heat keepability of the wool/nylon(50/50%) blend fabric by thermal manikin experiment was superior than that of wool 100% fabric, this result was verified with human-body wearing experiment and its result coincided well with this experimental result. Tactile wearing performance of the wool/nylon(50/50%) fabric from fabric mechanical properties measured by FAST system was better than that of the wool 100% fabric. The dimensional stability of the wool/nylon(50/50%) fabric was more stable than that of the wool 100% fabric. Because relaxation shrinkage was lower and hygral expansion of wool 100% fabric was more high. However, the breathability and pilling property of the wool/nylon(50/50%) fabric were inferior than those of the wool 100% fabric. The possibility of application for tra-biz garment of wool/nylon(50/50%) blend fabric was observed because of good heat keepability, tactile wearing performance and washing fastness.

• 복식문화연구
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• 제21권4호
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• pp.521-534
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• 2013

This study aims to identify the formative features of inflatable fashion that has changed its form or fulfilled specific functions by inserting air between fabrics or between clothes and the human body. Images of inflatable fashion images after the 1990s were collected from the literature and internet data and were analyzed based on the formative features of inflatable design. Through this analysis, it was determined that there were four formative features of inflatable fashion: First, inflatable fashion has functionality. General fashion also has functionality, but inflatable fashion has expanded functionalities such as an air bag effect or insulation due to injected air. Second, the formative potential. Inflatable fashion can be changed into different forms depending on the amount of air injected. Light-weighted air holds up the material of the clothes. So new forms that are different from conventional fashion, which gives inflatable fashion its formative potential, can be suggested. Third, aesthetic expansion. Inflatable fashion when its volume is expanded expresses the beauty of scale, or expresses a voluptuous beauty when part of human body is exaggerated. Fourth, it has an unconstructive characteristic. Space that is visible due to the transparent material of inflatable fashion expresses the intention of the designer to fulfill an unconstructive concept. In conclusion, the formative features of inflatable design have formative significances : practicality, aesthetic significance, semantics and technical significance.

• Transactions on Electrical and Electronic Materials
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• 제6권1호
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• pp.18-21
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• 2005

Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understanding of the relationship between the structure and function of the monolayers. Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuirfilms. MDC flowing across monolayers is analyzed using a rod-like molecular model. A linear relationship between the monolayer compression speed a and the molecular area Am. Compression speed a was about 30, 40, and 50 mm/min. Langmuir-Blodgett(LB) layers of Arachidic acid deposited by LB method were deposited onto slide glass as Y-type film. The structure of manufactured device is Aul Arachidic acid! AI, the number of accumulated layers are $9{\sim}21$. Also, we then examined of the Metal-Insulator-Metal(MIM) device by means of I-V. The I-V characteristics of the device are measured from -3 to+3 V. The insulation property of a thin film is better as the distance between electrodes is larger.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.80-82
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• 2002

To solve the difficulty in obtaining transmission routes and substation sites. increase the transmission capacity between generation sites and load centers. and enhance the stability of the power system. we have constructed and operated the 765kV double circuit transmission line(hereunder T/L) from the Dangjin thermal power plant and the Uljin nuclear power plant to the metropolitan. It makes it possible for us to accumulate know-how of the 765kV system that is the highest operating system level in Asia. As the second 765kV project, we are going to construct the 765kV single circuit T/L between Ansung and Gap yung. Because of the different electrical and mechanical characteristics. we are in need of different design technology. This paper presents the optimal design of 765kV single circuit transmission line after due consideration about the arrangement of conductors. the shape of a tower, insulation, etc.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1054-1056
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• 1999

It is necessary to install the arc generation facility to obtain the important technology for the design of breakers and switches, and the improvement of their performance and reliability. With this facility it is possible to study the characteristics of Arc in air/gas/vacuum insulation environment. The arc generation facility briefly consists of capacitor bank which can charge enormous energy, an air-core reactor, and several measurement equipments. This facility can simulates the arc phenomena in breakers and switches by means of generating high currents. In order to the protect electrode damage during the arcing time in arc extinguishing chamber, we installed auxiliary current source in addition to main capacitor bank, This auxiliary current source produces relatively small arc between electrodes before high current generation by main capacitor bank. Therefore it is possible to observe and measure the arcing phenomenon without damage of electrodes.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.950-952
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• 1999

In this paper, we are studied a electrical properties study with P.D.GEORGE/STER LING Co. P.B 302-LV-2 POLYBUTADIENE RESIN which is used for VPI(Vacuum Pressure Impregnation)processing of field magnet and armature of traction motor in Korean national railroad at present was carried out its FT-IR (Fourier Transform Infra-Red) volume resistivity characteristics. The varnishes were experimented with the temperature range form $25[^{\circ}C]$ to $180[^{\circ}C]$ and applied voltage were supplied at 100, 250, 500, 1,000[V]. In this condition, the volume resistivity for specimens were measured. From the above study, the following data obtained for volume resistivity. It can be confirmed that velume resistivity with the increase of temperature is lower rapidly from room temperature to $130[^{\circ}C]$, and it is lower slowly at temperature higher than $130[^{\circ}C]$. Volume resistivity value is higher, according as the specimen is thick gradually. As the applied voltage is higher in the same temperature, volume resistivity value is lower.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.912-914
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• 1999

Composite insulation system of liquid nitrogen and solid spacer is widely applied in high temperature superconducting power machine. This study has three step procedure. As follow, first step is composition of parallel deposited electrode and vertically deposited electrode along the direction of immersion in liquid nitrogen($LN_2$). Second step is investigation into surface flashover voltage of solid spacer under partially immersed in $LN_2$, and last step is comparison the result of this research with that of fully immersed in $LN_2$ and at cryogenic temperature gaseous nitrogen($GN_2$). This result presented that surface flashover voltage along solid spacer half immersed in $LN_2$ was almost the same as that of fully immersed spacer when the thickness of spacer(t) was t<10 mm. In the case of t>10 mm, however, spacer flashover voltage was equal to that obtained in $GN_2$ at cryogenic temperature.