• 제목/요약/키워드: LTS

검색결과 183건 처리시간 0.029초

저온초전도전원장치의 시스템 특성해석 및 요소실험 (Characteristic Analysis and Experiments on Components of Low-Tc Power Supply)

  • 윤용수;주민석;고태국
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제53권2호
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    • pp.76-81
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    • 2004
  • This paper deals with characteristic analysis and experiments on components of low-Tc(LTS) power supply. A LTS power supply consists of two exciters, a rotor, a stator, and an LTS magnet. The power supply has eight rotating poles, which make rotational magnetic flux. These flux penetrate superconducting sheets and cause currents which charge an LTS load. In this experiment, a 25.8mH LTS magnet was used, and rotor revolutions from 30 to 300rpm were used. In order to measure the pumping-current with respect to the magnet flux changes, a hall sensor was installed at the center of the LTS magnet. The experimental observations have been compared with the theoretical predictions. In this experiment, the pumping-current has reached about 372A.

LTS 명세 검증을 위한 모델 검증기 개발 (A Study on Implementation of Model Checking Program for Verifying LTS Specification)

  • 박용범;김태균;김성운
    • 한국정보처리학회논문지
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    • 제5권4호
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    • pp.995-1004
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    • 1998
  • 본 논문은 LTS 프로세스 명세 검증을 위해 프로토콜의 행위와 상태에 대한 deadlock, livelock, reachability, liveness 검증을 위한 모델 검증기 구현에 대해 기술하였다. Modal mu-calculus를 사용하여 구현된 모델 검증기는 modal logic으로 표현된 프로토콜 특성이 LTS 명세하에서 만족하는지를 자동적으로 검증해 주는 model checking 도구이고 LTS 명세의 Safety와 Liveness 검증에 매우 강력한 성능을 보이는 것을 구현을 통해 실험적으로 증명하였다. 제시된 도구는 Windows NT 환경하에서 IBM PC로 $C^{++}$언어를 사용하여 구현되었다.

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LMDS용 평면형 안테나의 실용화 방안 (A Study on the Practice Method of Planar Antenna for LMDS)

  • 이형수;설동범;이윤경;윤현보
    • 한국전자파학회논문지
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    • 제11권3호
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    • pp.474-483
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    • 2000
  • 본 논문에서는 LMDS용 평변형 안테나로 28 GHz에서 동작하는 LTS 안테나와 Vivaldi 안테나를 시간영역 유한차분법(Finite Difference Time Domain Method)를 이용하여 최적화한 후 제작 및 측정하였다. 부엽의 크기 를 줄이기 위하여 corrugation 구조를 설계한 평변형 안테나에 적용하여 FDTD 방법으로 최적화 한 후, 제작 및 측정하였다. 측정결과, corrugation 구조를 갖는 LTS 안테나와 Vivaldi 안테나의 부엽의 크기가 약 4 dB 감소됨을 확인하였다.

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정밀 좌표측정용 머신비전 시스템의 광학적 해석에 관한 연구 (A Study on the optical aspects of machine vision based dimensional measurement system)

  • Lee, E.H.
    • 한국정밀공학회지
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    • 제11권2호
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    • pp.149-163
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    • 1994
  • A novel method of dimensional measurement using machine vision, which is called Landmark Tracking System, has been developed. Its advantages come form tracking only the bright, standard shaped "landmarks" which are made from retroreflective sheets. In the design of the LTS, it is essential to know the relationship between optical parameters and their influence on system performance. Such optical parameters include the brightness of landmark image, the illumination system design, and the choice of imaging optics. And the performance of retroreflective material also plays important role in the LTS performances. Influences of such optical parameters on LTS's dimensional measurement characteristics are investigated, with respect to the retroreflective material, the imaging optics, and the illumination system. Measuremtn errors due to parameter variations are also analyzed. Experiments are performed with a LTS prototype. Retroreflective characteristics are verified, and the LTS's measurement performances are measured in the form of repeatability and accuracy. Experimental results shgow that the LTS has repeatability better than 1/30,000 of a field of view(30 degrees), and accuracy better tha 1/3,000 of a field fo view.d fo view.

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초보자에서 후두튜브기도기와 후두마스크기도기의 삽관 비교 - 마네킨 연구 - (Comparison between laryngeal tube suction II and laryngeal mask airway in novice users - A manikin study -)

  • 황지영;조근자
    • 한국응급구조학회지
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    • 제16권3호
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    • pp.19-28
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    • 2012
  • Purpose : The present study was designed to provide basic data for advanced pre-hospital airway management by comparing the insertion time and success rate between laryngeal tube suction II (LTS II) and laryngeal mask airway (LMA) in a manikin. Methods : A total of 32 participants were novice users to both of devices among paramedic students. After taking the introductory lecture and demonstrations, the participants made an attempt to insert the LTS II and LMA to compare the insertion time and success rate. They marked the easiness of insertion of the score ranged from 1 to 10 score scale and preference of the two devices. Results : The insertion time of the LTS II was significantly shorter than that of the LMA (p =.000). There was no significant difference between LTS II and LMA in the success rate. In the easiness of insertion, the score of LTS II $(8.47{\pm}1.41score)$ was significantly higher than that of LMA $(7.19{\pm}1.98score)$(p =.001). The preference of LTS II (75%) was much higher than that of LMA (25%). Conclusion : The manikin study data showed that the LTS II may be a good alternative airway device for providing and maintaining a patent airway.

A Study on Prototype Hybrid (LTS/HTS) Magnet for NMR Application

  • Choi, Suk-Jin;Hwang, Young-Jin;Ko, Tae-Kuk
    • Journal of Magnetics
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    • 제16권3호
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    • pp.312-317
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    • 2011
  • NMR over 1 GHz (23.5 T) level has difficulties in design and fabrication with only low temperature superconducting (LTS) wire because of its material characteristics such as the decay of critical current under the magnetic field. Because High temperature superconducting (HTS) tape has a good performance under the extremely high magnetic field, it has been developed for high-field magnet over 23.5 T. In this paper, the LTS magnet was made for applying magnetic fields externally and the HTS coil was designed and fabricated. The electromagnetic field analysis has been done with respect to the structure and the operating current of the LTS and HTS coil. Considering to the field homogeneity and the center field, the design parameters which is suitable for the HTS coil were found. The HTS insert coil was impregnated with epoxy resin in order to prevent the movement of winding during energizing the magnet. The hybrid magnet (LTS/HTS) magnet was fabricated and tested based on the design parameters. The experimental result shows that the LTS background magnet and the HTS insert coil can be operated stable beyond 220 A and 210 A. The final value 4.32 T at the center was acquired.

딥러닝을 이용한 경량혼합토의 일축압축강도 예측 시스템 (Predictive System for Unconfined Compressive Strength of Lightweight Treated Soil(LTS) using Deep Learning)

  • 박보현;김두기;박대욱
    • 한국구조물진단유지관리공학회 논문집
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    • 제24권3호
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    • pp.18-25
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    • 2020
  • 경량혼합토의 일축압축강도는 배합비에 크게 의존한다. 경량혼합토와 다양한 경량혼합토의 구성성분들의 관계를 특징짓기 위한 기존연구에서는 시험을 통한 회귀모델을 사용하여 정규화계수를 제안하였다. 그러나 실내시험에서 얻은 결과는 재료와 배합비사이의 관계가 복잡하기 때문에 일정한 예측의 정확도를 기대할 수 없다. 이 연구에서는 다양한 배합조건에서 수행된 실내시험결과를 바탕으로 심층신경망 모델을 적용함으로써 경량혼합토의 일축압축강도를 예측하였다. 제안된 심층신경망 모델을 사용함으로써 설계 배합조건으로 구성된 경량혼합토의 일축압축강도 값을 합리적으로 산정할 수 있다.

순간전압강하 저감을 위한 방사상 배전계통에서의 부하 절환 스위칭 (Load Transfer Switching for Reducing the Voltage Sag's Effect in Radial Power Distribution System)

  • 윤상윤;김재철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 추계학술대회 논문집 학회본부 A
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    • pp.208-210
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    • 2000
  • In this paper, we present a method for mitigating the effect of voltage sag in radial power distribution systems using load transfer switching (LTS). The term of LTS is defined that the weakness load points for voltage sag transfer to the alternative source during the fault clearing practices. The sequences of proposed LTS method is divided into the search of weakness points for voltage sag using the risk assessment model and transfer behavior of weakness points. Through the case studies, we verify the effectiveness of proposed LTS method and present the searching method of effective application points of LTS method using the risk assessment model.

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부하 절환 스위칭을 이용한 방사상 배전계통에서의 순간전압강하 대책 (Countermeasure of Voltage Sag in Radial Power Distribution System using Load Transfer Switching)

  • 윤상윤;오정환;김재철
    • 대한전기학회논문지:전력기술부문A
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    • 제49권11호
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    • pp.558-565
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    • 2000
  • In this paper, we propose a method for mitigating for mitigating the effect of voltage of voltage sag in radial power distribution systems using load transfer switching (LTS). The term of LTS is defined that the weakness load points for voltage sag transfer to the alternative source during the fault clearing practices. The sequenced of proposed LTS method is divided into the search of weakness points for voltage sag using the risk assessment model and transfer behavior of weakness points. The search of weakness point is carried out using the risk assessment model of voltage sag and Monte Carlo simulation method and the historical reliability data in Korea Electric Power Corporation (KEPCO) are also used. Through the case studies, we verify the effectiveness of proposed LTS method and present the searching method of effective application points of LTS method using the risk assessment model.

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Regulation of adductor muscle growth by the IGF-1/AKT pathway in the triploid Pacific oyster, Crassostrea gigas

  • Kim, Eun-Young;Choi, Youn Hee
    • Fisheries and Aquatic Sciences
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    • 제22권9호
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    • pp.19.1-19.10
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    • 2019
  • We investigated the insulin-like growth factor 1 (IGF-1)/AKT signaling pathway involved in muscle formation, growth, and movement in the adductor muscle of triploid Pacific oyster, Crassostrea gigas. Large and small triploid oysters (LTs and STs) cultured under identical conditions were screened, and the signaling pathways of individuals with superior growth were compared and analyzed. mRNA and protein expression levels of actin, troponin, tropomyosin, and myosin, proteins important in muscle formation, were higher in LTs compared with STs. Expression levels of IGF-1, IGF binding protein (IGFBP), and IGFBP complex acid-labile subunit were also higher in LTs compared with STs. Phosphorylation of the IGF receptor as well as that of AKT was high in LTs. In addition, the expression of phosphomammalian target of rapamycin and phospho-glycogen synthase kinase $3{\beta}$ was increased and the expression of Forkhead box O3 was decreased in LTs. Therefore, we suggested that the IGF-1/AKT signaling pathway affects the formation, growth, and movement of the adductor muscle in triploid oysters.