• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.838-840
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• 1998

$BiNbO_4$ ceramics with 0.06wt% CuO, 0.1wt% $V_{2}O_{5}$ sintered at $900^{\circ}C$. The strip line chip filter has been design and fabricated by screen printing with silver electrode after tape casting. The characteristics of the fabricated filters were compared with the simulated results. In the strip line chip filter, insertion loss value of band pass width was 3.65[dB] and return loss was 8.9[dB] and center frequency was similar that simulation results.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 1999년도 제1회 학술대회논문집(KIASC 1st conference 99)
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• pp.54-57
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• 1999

AC losses per cycle properties at 77K have been investigated on the Ag sheathed Bi2223 wire through two kinds of measuring methods(transport method and magnetic method). In case of transport method, the absolute value of losses agree with the results of Norris theory(strip and ellipse). In case of 19-filamentary tape, AC transport losses almost agree with those of magnetic method. In case of 1-filamentary tape, However, AC losses of magnetic method is smaller than AC transport losses

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권7호
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• pp.437-443
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• 2004

In this work the AC loss measurement setup based on an iron core background magnet, not used in a conventional one, has been successfully developed. To prove its validity, a round-robin test for the same Bi-2223 tape sample among three institutes has been done. The results show that the self-field and magnetization losses from the developed setup well agree with the losses measured at two other institutes of Korea Basic Science Institute and Yokohama National University. The measured magnetization losses for parallel or perpendicular fields can be well predicted from the slab model or the strip model for a filamentary region. However the magnetization losses for longitudinal fields can be rather predicted by the slab model for a decoupled filament. The self-field losses are well explained by the Norris ellipse model.

• 한국항공우주학회지
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• 제47권10호
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• pp.712-719
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• 2019

본 연구에서는 최근 다양한 큐브위성 임무에 사용되는 테이프 스프링 힌지의 거동 해석을 수행하였다. 테이프 스프링은 곡선 단면을 갖는 직선형의 얇은 스트립이며 곡률에 따라 달라지는 강성변화로 인해 비선형성이 강하게 발생한다. 이전 연구에서 제시된 회전-모멘트 선도 모델을 바탕으로 테이프 스프링의 거동 특성을 분석하였으며, 시중에 판매되는 상용 테이프 스프링 형상을 정확하게 모사하여 ABAQUS 수치 해석을 진행하였다. 테이프 스프링을 굽히는데 소요되는 최대 모멘트를 예측하였으며 단면의 원호각이나 두께 등의 변화에 따른 파라미터 스터디를 수행하였다. 또한 간략한 실험을 통해 수치해석 결과를 비교 검증하여 보다 정밀한 큐브위성 동적 거동 해석을 위한 향후 연구 방향을 제시한다.

• Progress in Superconductivity
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• 제6권1호
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• pp.32-36
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• 2004

To investigate the influence of strip width and inter-strip separation on the ac loss, arrays of parallel strips with different widths and separations were prepared. Studies on the hysteresis-loss characteristics of multifilamentary YBCO films were performed. The local magnetic field due to magnetization currents is measured by a scanning Hall probe microscope. Based on these results a conceptual design for a low loss YBCO coated conductor is suggested.

• Progress in Superconductivity
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• 제6권2호
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• pp.99-103
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• 2005

For ac applications a detailed understanding of the ac power losses associated with different conductor configurations is of crucial importance. YBCO thin films were divided into parallel filaments with widths of 1, 2, and 4 mm to reduce hysteresis losses. The measured hysteresis losses show a linear relationship between the strip width and hysteresis loss as anticipated. The influence of different inter-filament separations on the hysteresis loss is investigated.

• 한국기계가공학회지
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• 제15권6호
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• pp.9-15
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• 2016

Due to material-specific vulnerabilities, the surfaces of the liquid crystal glasses used in mobile phones can crack easily, with even the smallest cracks undergoing propagation. To protect the glass surfaces, films are attached to the surfaces during the mobile phone production process. However, after machining the liquid crystal, removal of the film on the liquid crystal surface using chemical and mechanical methods is required. In this research, a peeling apparatus was developed for removing the films attached to liquid crystal surfaces during the production process. Mechanical attachment and design automation through experimentation and finite element modelling were performed to confirm the validity of the design.

• Journal of Advanced Marine Engineering and Technology
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• 제40권7호
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• pp.642-646
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• 2016

본 논문에서는 종이에 전도성 테이프를 이용하여 만든 웨어러블 안테나를 소개한다. 제안하는 안테나는 A4 복사 용지에 반파장 도체 다이폴 스트립과 기생 도체 스트립으로 구성이 되며, SMA 커넥터를 통해 다이폴의 중앙에 급전되는 구조이다. 제안하는 안테나의 모양은 종이 접기에 따라 모양이 달라지며, 따라서 종이를 접었을 때와 펼쳤을 때 안테나의 방사패턴이 가변된다. 이것은 안테나 방사패턴의 영점(null)에 의해 신호의 수신율이 낮아지는 문제점을 해결할 수 있다. 제안하는 안테나의 반사계수와 방사패턴을 900 MHz에서 시뮬레이션과 실험을 통해 제시하였고, 제안하는 종이 안테나가 900 MHz에서 종이접기 방식에 따라 재구성(reconfigurable) 특성이 있음을 보였다.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2004년도 High Temperature Superconductivity Vol.XIV
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• pp.49-49
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• 2004

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권10호
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• pp.554-559
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• 2002

The at loss is an important issue in the design of superconducting cables and transformers. In these devices the Bi-2222 tapes are usually placed face-to-face. In such arrangements ac loss is influenced by adjacent tapes. The effect is investigated by measuring the magnetization loss in the stacked conductor, which consists of various numbers of Bi-2223 tapes. For the single tape the magnetization loss in perpendicular field is larger than that in parallel field by about a factor 10. This agrees well with the prediction for hysteresis loss in slab and strip models. For the stacked conductor in perpendicular field the magnetization loss at low fields is greatly decreased, compared to the loss of the single tape. However the loss at high fields is nearly unaffected. This behavior is well described by the slab model.