• 제목/요약/키워드: inductive

검색결과 1,459건 처리시간 0.027초

가공송전선 유도장해 특성을 고려한 최적 상배열 연구 (Study on Optimal Phase Arrangement Considering the Characteristics of Inductive Interference from Overhead Transmission Lines)

  • 강경두;김진규
    • 전기학회논문지
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    • 제68권1호
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    • pp.13-18
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    • 2019
  • The domestic overhead transmission lines use a vertical configuration and reverse phase arrangement, but when there is a limitation in steel tower height because the transmission lines pass a height limit zone or special zone, an application of triangular arrangement is necessary, and a study on the optimal phase arrangement to minimize inductive interference for this is necessary. If conductor arrangement are changed, the action of electrostatic induction and electromagnetic induction becomes different from before changes, so the changed conductor arrangement should be reviewed in terms of inductive interference. So this paper presents an optimal phase arrangement to reduce inductive interference by calculating electrostatic induction and electromagnetic induction according to conductor arrangement.

반도체 제조장비용 무접점 Inductive Coupler의 성능개선을 위한 연구 (A Study on the Performence improvment of Contactless Inductive Coupler for the Stocker System)

  • 김현우;반상호;권호;박재범;이주;이철직;김석태;김준호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 B
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    • pp.923-925
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    • 2002
  • The existing contactless inductive coupler has many problems because of its large volume and high level of exciting current, so a new contactless inductive coupler is being required under the circumstances and the load requirement. For a contactless inductive coupler in the manufacturing equipment of semiconductor, the coupler's efficiency is low because of its small magnetic inductance and large leakage inductance. Moreover, the high frequency switching to increase energy density per unit volume increases the iron loss and the eddy current loss, so it must be considered deeply when selecting core materials. Therefore, this paper presents core materials and shape to improve the performance of the contactless inductive coupler according to the coil positions.

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Hammett 치환기 상수에 대한 분자궤도론적 해석 (I) (Molecular Orbital Analyses on Hammett Substituent Constant (I))

  • 박병각;이갑룡
    • 대한화학회지
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    • 제30권2호
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    • pp.172-180
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    • 1986
  • 치환-벤조산, -베젠 및 -나프탈렌의 세 계열에 대해 LCAO MO법으로 Hammett치환기 상수를 해석하였다. Hammett ${\sigma}$값은 이론적으로 유도효과와 공명효과의 독립적인 기여의 합으로 취급됨을 알았다. 즉, 유도효과를 정적유도효과(static inductive effect, Is)와 동적유도효과 (dynamic inductive effect, Id)로 나누어 각각 net charge 및 근사자기편극률 지수로 취하고 공명효과로서 치환 분자와 비치환분자의 HOMO에너지 차$({\Delta}E^{HOMO})$로 취하였으며 계산결과 Hammett ${\sigma}$값은 정적유도효과, 동적유도효과 및 ${\Delta}E^{HOMO}$의 합에 의존됨을 알았다.

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실천추론에 의한 귀납의 정당화 (A Vindication of Induction by Practical Inference)

  • 이병덕
    • 논리연구
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    • 제12권2호
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    • pp.59-88
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    • 2009
  • 귀납추론은 연역추론이 아니기 때문에 연역적으로 정당화될 수 없다. 또한 귀납추론을 귀납적으로 정당화하는 것은 순환적이다. 따라서 흄은 귀납추론을 합리적으로 정당화할 수 없다고 주장한다. 흄이 이와 같은 귀납의 문제를 제기한 이후 오랜 동안 많은 철학자들이 이 문제를 해결하고자 시도해 왔다. 그럼에도 불구하고, 아직껏 대다수의 철학자들이 동의하는 해결책이 제시되지 않고 있다. 셀라스에 따르면 귀납의 문제는 이론추론이 아니라 오직 실천추론을 통해서만 해결할 수 있다. 이 논문은 셀라스가 제안한 실천추론에 의한 귀납의 정당화를 좀 더 명확한 형태로 발전시켜 설명함으로써 그의 해결책이 귀납의 문제에 대한 근본 해결책임을 주장한다.

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Increased impedance by quench at a shield layer of HTS power cable for fault current limiting function

  • Choi, Youngjun;Kim, Dongmin;Cho, Jeonwook;Sim, Kideok;Kim, Sungkyu;Kim, Seokho
    • 한국초전도ㆍ저온공학회논문지
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    • 제21권4호
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    • pp.59-63
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    • 2019
  • To reduce the fault current below the current capacity of a circuit breaker, researches on HTS (High Temperature Superconductor) power cables with fault current limiting (FCL) function are increasing. An FCL HTS power cable transports current with low a impedance during normal operation. Yet, it limits the fault current by an increased inductive or resistive impedance of conducting layer when quench occurs at the FCL HTS power cable by the large fault current. An inductive type FCL HTS power cable uses increased inductive impendence caused by leakage magnetic flux outside the cable core when the quench occurs at a shield layer losing the magnetic shielding effect. Therefore, it has an advantage of less resistive heating than resistive type FCL HTS power cable and temperature increase is suppressed. This paper describes an ideal circuit model for the FCL HTS power cable to investigate the effectiveness of increased inductive impedance when quench occurs at the shield layer. Then, FEM analysis is presented with a simplified model cable composed of various iron yokes to investigate the effect of the shape of yoke on the generation of the inductive impedance.

배지 성분에 따른 인간 지방조직기원 CD146 양성 혈관내피세포의 증식 및 기능의 평가 (Proliferation and Functional Activity of Human Adipose Tissue-Derived CD146 Positive Endothelial Cells According to Culture Mediums)

  • 박봉욱;하영술;김진현;조희영;정명희;김덕룡;김신원;김욱규;김종렬;변준호
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제32권6호
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    • pp.504-510
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    • 2010
  • Purpose: This study was to examine the proliferation and function of the adipose tissue-derived endothelial cells according to different culture medium conditions. Materials and Methods: Adipose tissue-derived CD146 positive endothelial cells were cultured in according to different culture mediums (DMEM culture medium with or without osteogenic inductive agents and EBM-2 culture medium with or without osteogenic inductive agents). The proliferation and function of the adipose tissue-derived endothelial cells was examined in different culture medium conditions. Results: Adipose tissue-derived endothelial cells formed tube-like structures on Matrigel in EBM-2 culture medium with or without osteogenic inductive agents. However, the cells did not form tube-like structures on Matrigel in DMEM medium with or without osteogenic inductive agents. After 24 hours of culture, among the culture medium using EBM-2, the proliferation of the cells were promoted in EBM-2 medium without osteogenic inductive agents than in EBM-2 medium with osteogenic inductive agents. However, 72 hours of culture, the proliferation of the cells were promoted in EBM-2 medium with osteogenic inductive agents than in EBM-2 medium without osteogenic inductive agents. Conclusion: These results suggest that the proliferation and function of the adipose tissue-derived CD146 positive endothelial cells could be maintained in EBM-2 with osteogenic inductive agents.

골막기원세포의 조골세포 분화과정에서 나타나는 혈관내피전구세포의 증식 (PROLIFERATION OF ENDOTHELIAL PROGENITOR CELLS BY OSTEOGENIC DIFFERENTIATION OF PERIOSTEAL-DERIVED CELLS)

  • 김종렬;송정호;김욱규;박봉욱;하영술;김진현;김덕룡;조영철;성일용;변준호
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제35권4호
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    • pp.205-212
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    • 2009
  • Purpose : The purpose of this study was to examine the expression of various angiogenic factors during osteoblastic differentiation of periostealderived cells and the effects of osteogenic inductive medium of periosteal-derived cells on the proliferation of endothelial progenitor cells. Materials and methods : Periosteal-derived cells were obtained from mandibular periosteums and introduced into the cell culture. After passage 3, the cells were divided into two groups and cultured for 21 days. In one group, the cells were cultured in the DMEM supplemented with osteogenic inductive agent, including 50g/ml L-ascorbic acid 2-phosphate, 10 nM dexamethasone and 10 mM -glycerophosphate. In the other group, they were cultured in DMEM supplemented without osteogenic inductive agent. VEGF isoforms, VEGFR-1, VEGFR-2, and neuropilin-1 mRNA expression was observed. Human umbilical cord blood-derived endothelial progenitor cell proliferation was also observed. Results : The expression of VEGF isoforms was higher in osteogenic inductive medium than in non-osteogenic inductive medium. The expression of VEGFR-2 was also higher in osteogenic inductive medium than in non-osteogenic inductive medium. However, the expression of VEGFR-1 and neuropilin-1 was similar in both osteogenic inductive medium and non-osteogenic inductive medium. In addition, conditioned medium from differentiated periosteal-derived cells stimulated human umbilical cord blood-derived endothelial progenitor cell numbers compared to conditioned medium from non-differentiated periosteal-derived cells. Conclusion : These results suggest that in vitro osteoblastic differentiation of periosteal-derived cells has angiogenic capacity to support endothelial progenitor cell numbers.

패치의 길이와 비아의 반경이 Inductive Loaded Patch Antenna의 방사 특성에 미치는 영향 (Effect of the Patch Length and Via Radius on the Radiation Characteristics of an Inductive Loaded Patch Antenna)

  • 곽은혁;윤영민;김부균
    • 대한전자공학회논문지TC
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    • 제49권6호
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    • pp.48-56
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    • 2012
  • 서로 다른 유전 상수를 가지는 기판에서 반 파장 길이 공진 모드를 이용한 ILPA (Inductive Loaded Patch Antenna)와 일반적인 패치 안테나를 설계하여 방사 특성에 대하여 연구하였다. 설계한 ILPA는 일반적인 패치 안테나보다 수평 방향으로의 방사가 억제되고 전방 이득이 향상되는 특성을 가진다. 수평 방향으로의 방사가 가장 크게 억제되며 전방 이득이 가장 큰 ILPA의 방사 패치의 길이와 via 반경이 존재함을 보인다.

개구면 결합 급전을 이용한 Inductive Loaded 마이크로스트립 패치 안테나 (Inductive Loaded Microstrip Patch Antenna Using Aperture Coupled Fed)

  • 구환모;윤영민;김부균
    • 전자공학회논문지
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    • 제49권9호
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    • pp.35-42
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    • 2012
  • 개구면 결합 급전 방법을 이용하여 inductive loaded 마이크로스트립 패치 안테나를 설계하고 병렬 스터브를 이용하여 임피던스 대역폭을 넓히는 방법에 대해 연구하였다. 급전선로에 병렬 스터브를 삽입하여 AIMPA의 임피던스 대역폭을 확장시켰다. 병렬 스터브를 삽입한 AIMPA의 -10 dB 임피던스 대역폭은 5.51 %로 병렬 스터브를 삽입하지 않은 AIMPA의 임피던스 대역폭 2.4 %와 비교하여 대역폭이 약 129.6 % 증가함을 볼 수 있었다. -10 dB 대역폭 내에서 방사 패턴의 전체적인 모양은 크게 변화하지 않음을 확인하였다.

Inductive Micro Displacement Detecting System with High Sensitivity and Low Linearity Error

  • Park, Dong-June;Park, In-Mook;Kim, Soo-Hyun
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권3호
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    • pp.54-60
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    • 2001
  • A newly designed inductive micro displacement detecting system is presented. The proposed inductive system consists of driving coils, position-detecting coils, cores, and closed-loop formed magnetic blocks. The cores and magnetic blocks are made of Mn-Zn ferrite. When AC sine wave is applied to the driving coils, the time derivative flux is generated within the system, and then induced voltages arise in the position-detecting coils according to the core\`s position. Putting the cores to be moved proportionally to the input displacement, the induced voltage is proportional to input displacement. The parameters that affect the system characteristics are turn ratio, air-gap size, excitation frequency, overlap area, load resistance, capacitance effect, and so forth. Based on the experimental results, the system parameters are selected in such a way as to have high sensitivity ad stable responses. The sensitivity of the proposed inductive displacement-detecting system is greater than 2800mV.V-1mm-1 and the linearity error is below $\pm$0.10% in the range of $\pm$200㎛.

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