• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2003.11a
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• pp.279-281
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• 2003

We analysed the operating properties of resistive type superconducting fault current limiters (SFCLs) based on YBCO thin films with a single line-to-ground fault. When a single line-to-ground fault occurred, the short circuit current of a fault phase increased up to about 6 times of transport currents immediately after the fault instant and was effectively limited to the designed current level within 2 ms by the resistance development of the SFCL. The fault currents of the sound phases almost did not change because of their direct grounding system. The unsymmetrical rates of a fault phase were distributed from 6.4 to 1.4. It was found that the unsymmetrical rates of currents were noticeably improved within one cycle after the fault instant. We calculated the zero phase currents for a single line-to-ground fault using the symmetrical component analysis. The positive sequence resistance was reduced remarkably right after the fault but eventually approached the balanced positive resistance component prior to the system fault. This means that the system reaches almost the three-phase symmetrical state in about 60 ㎳ after the fault. The ground currents were almost 3 times of the zero phase mts since most of the fault currents flowed through the grounding line.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1996.12a
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• pp.64-64
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• 1996

Transgenic animal and cell line models which are recently developed in toxicology field combined with molecular biological technique, are powerful tools for studying of mutation in vivo and in vitro, respectively. The Big Blue mutagenesis assay system is one of the most widely used transgenic systems. Especially, for the study of direct acting mutagens, Big Blue cell line is very useful and powerful to evaluate mutagenicity because the mutation frequency and mutationspectrlun showed no distinct differences between cell line and animal. The Big Blue cell lines carry stably integrated copies of lambda shuttle vector containing lac I gene as a mutational target. These lambda shuttle vectors are useful for various mutagenesis related studies in eukaryotic system due to their ability to be exposed mutagen and then transfer a suitable target DNA sequence to it convenient organism for analysis. We tried to assess the mutagenic effect of 4-NQO with Big Blue cell line. After the treatment of 4-NQO, genomic DNA was isolated and lambda shuttle vector was packaged by in Vitro packaging and then these were plated on bacterial host in the presence of X-gal to screen mutation in the lac I. We determined MF as a ratio of blue plaques versus colorless plaques and now undergoing the mutation spectrum of 4-NQO in lac J gene sequence.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.11
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• pp.1925-1929
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• 2007

This paper is studied on a novel Electric Safety Protection Device (ESPD) of high speed for incapable operation of Earth Leakage Circuit Breaker (ELB) and Molded_case Circuit Breaker (MCCB) using the low voltage distribution line. The major causes of electrical fire are classified to short circuit fault, overload fault, electric leakage and electric contact failure. The occurrence factor of the fire is electric arc or spark accompanied with electrical faults. Residual Current Protective Device (RCD), that is ELB and MCCB, of high sensitivity type used at low voltage wiring cuts off earth leakage and overload, but the RCD can't cut off electric arc or spark to be a major factor of electrical fire. As the RCDs which are applied low voltage distribution panel are prescribed to rated breaking time about 30[ms] (KS C 4613), the RCDs can't perceive to the periodic electric arc or spark of more short wavelength level. To be improved on such problem, this research development is proposed to a novel ESPD of high speed to trip of distribution line on electric arc or spark due to electrical fire. Some experimental results of the proposed ESPD are confirmed to the validity of the analytical results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.10
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• pp.2339-2344
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• 2014

of a microstrip transmission line, this transmission line can operate as the microstrip line or the coplanar line according to open or short connection between the ungrounded copper plane and grounded plane on the base plane. Two different type operation of the transmission line means that one transmission line can have two different characteristic impedances. This paper proposes and fabricates the circuit to be operated 2-ports power transmission line or 2-way power divider with the stable input matching characteristic by using this dual-impedance transmission line. The proposed circuit operates 2-ports power transmission line in case of the coplanar line or 2-way power divider line in case of the microstrip line. The fabricated circuit shows $S_{21}$ > -0.2 dB and $S_{11}$ < -15 dB above 700 MHz when the circuit operates 2-ports power transmission line. And, it is $S_{21}$ > -3.8 dB, $S_{11}$ < -10 dB and $S_{21}/S_{31}$ < ${\pm}0.3dB$ above 700 MHz when the circuit operates 2-way power divider.

• The Journal of the Acoustical Society of Korea
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• v.32 no.4
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• pp.361-368
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• 2013

As one way to describe the behavior of a vibrating string, analogies to a transmission line have been made based on the fact that they have oppositely travelling waves on each of them. In such analogies, a rigid end to the string has been represented as an open circuit, and the displacement of the string as the current on the transmission line. However it turns out that the rigid end corresponds to a short circuit, the displacement to the voltage by the theory of the transmission line, and it is confirmed by experiments with circuit simulations. Based on these discoveries, a transmission line based plucked string model comprising a transmission line, two piecewise linear current sources, and switches is proposed. The proposed model is validated by showing that the voltage at the arbitrarily chosen location, and the voltage calculated over an infinitesimal portion at the end of the transmission line are consistent with the displacement at the corresponding location and the force on the rigid end of the string from the well known difference form of a wave equation governing the behavior of the string with its fundamental frequency tuned to that for the proposed model, respectively. Moreover, the applicability of the proposed model to modeling string and wind instruments is presented.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.616-619
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• 1995

This paper describes developement of on-line system for vibration signal analysis. In the power system, the main reason of transformer fault is due to a large amount of current by a short-circuit and a ground-fault. The electromagnetic force caused by fault-current deforms transformer windings and results in vibration pattern change. Therefore if the continuous on-line vibration monitoring on transformer is performed, an incipient failure can be detected. The developed system is composed of data acquisition devices, user interface program, signal processing program, diagnosis and trend analysis program, self diagnosis program and communication program.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.497-509
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• 2022

Lines are the oldest visual elements in human history and are closely related to human life and drawings and symbols drawn with lines on cave paintings and rocks have existed as alternative images for human survival. In arts the line reveals the core of the object within a short period of time and in art therapy it becomes a medium that can diagnose the client's psychological state and intervene therapeutically. However although line drawing has therapeutic importance in the process as well as diagnosis studies on its effectiveness and therapeutic characteristic have not been actively conducted. Therefore in this study the characteristics related to line art in art therapy are first derived through 'Triangular Verification of Theory', 'Qualitative Content Analysis', and 'Finding Common Parts' in domestic and foreign literature. As a result I will examine the Movement which is a key therapeutic element of line drawing in connection with the brain structure. Through this I will examine the therapeutic mechanisms that affect the body, brain and mind of the movement of line drawing and examine and suggest how it can be used in art therapy.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.8
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• pp.1420-1431
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• 2001

This research was done to classify lower body types by direct measurements, side and back view types from waistline to gluteal furrow line individually, and to analyze correspondence these lower body types with side and back view types from waistline to gluteal furrow line. The subjects of this study were 191 female college students from 18 to 25 years old residing in Pusan urban area. Type 1(long and slim) of lower body types by direct measurements was correspond with Type 1(slim curve) and Type 4(slim and protrusive hip) of side view and Type 3(wide and curve) and Type 4(trapezoid shape) of back view. Type 2(short and thick) of lower body types was correspond with Type 3(thick and droopy hip) of side view and Type 1(wide and straight) of back view. Type 3(short and slim) of lower body types was correspond with Type 2(slim and flat hip) of side view and Type 2(narrow and curve) of back view.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.1
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• pp.149-156
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• 2012

In this study, we propose a novel transmission line employing inverted PACD (Periodically Arrayed Capacitive Devices) for application to a development of miniaturized passive components on MMIC. The novel microstrip line employing Inverted PACD structure showed a loss much lower than conventional microstrip line. Using the inverted PACD structure, we fabricated a miniaturized impedance transformer on MMIC. the size of the impedance transformer was 0.012 $mm^2$, which is only 1.7% of conventional one. The impedance transformer showed good RF performances in a frequency range of 2.25~6.5 GHz.

• FLOWER RESEARCH JOURNAL
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• v.16 no.4
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• pp.317-320
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• 2008

A new spray chrysanthemum(Dendranthema grandiflorum Ramat.) cultivar 'Yes Line' was originated from a cross between 'T22319' and 'SP02-037-13'. This cultivar was tested on the characteristics from 2004 to 2007 for the evaluation and selection including shading and retarding culture. The natural flowering time of 'Yes Line' is late October, but year-round production is possible by shading, lighting and retarding culture. This cultivar was single in flower type, with a color of red-purple(RHS 74C), with the flowers of 21.4 per stem. 'Yes Line' showed the vase life of 16.5 days in autumn season. The diameters of flower and flower center were 4.3 cm, 1.2 cm respectively. The days to flower under the short day treatment was 7.5 weeks and preference of consumers were high at 3.86 ranged up to 5.00. It has resistance to white rust and was possible to cultivate all-year-round.