• 제목/요약/키워드: Resistance Coupling

검색결과 248건 처리시간 0.023초

Structure and Properties of the Organoclay Filled NR/BR Nanocomposites

  • Kim Won-Ho;Kim Sang-Kwon;Kang Jong-Hyub;Choe Young-Sun;Chang Young-Wook
    • Macromolecular Research
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    • 제14권2호
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    • pp.187-193
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    • 2006
  • Organoclay, was applied as a filler, in place of carbon black and silica, to a natural rubber (NR)/butadiene rubber (BR) blend. A compounding method was used to disperse and separate the layered silicates. The effect of a coupling agent on the vulcanizates was evaluated using both the silica and organoclay filled compounds. After the compounding processes were completed, the XRD diffraction peaks disappeared, but then reappeared after vulcanization. The scorch times for the organoclay-filled compounds were very short compared to those for carbon black and silica-filled compounds. The organoclay-filled compounds showed high values of tensile strength, modulus, tear energy, and elongation at the break. When ranked by viscosity, the compounds appeared in the following order: silica > silica (Si-69) > organoclay > organoclay (Si-69) > carbon black. Fractional hysteresis, tensile set, and wear rates were very consistent with the viscosity of the vulcanizates. The Si 69 coupling agent increased reversion resistance, the maximum torque values in the ODR, modulus, and wear resistance, but decreased elongation at the break, fractional hysteresis, and tension set of the vulcanizates.

웨어러블 디바이스 사용 결정요인: 행동경제학을 중심으로 (Determinants of Wearable Device Usage: Perspectives of Behavioral Economics)

  • 신명곤;손달호
    • 한국정보시스템학회지:정보시스템연구
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    • 제27권3호
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    • pp.181-202
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    • 2018
  • Purpose Wearable device is considered as one of the methods powering the growth of the next generation. However, ICT's innovation resistance has been a contributing factor in slowing down this spread of wearable devices. Taking into consideration the lack of empirical research to this phenomenon, this study served to examine the effect of determinants of wearable devices to usage with the perspectives of behavioral economics. Design/methodology/approach: For research purposes, this study developed research hypotheses in order to empirically examine the factors that might have a significant effect on the usage of the wearable device. The empirical research was based on a survey which carried through 500 participants. Research results were evaluated via SPSS Statistics 21.0 and AMOS 19 statistical package program. Findings: Results showed that perceived costs and benefits had a significant effect on coupling. It means that perceived benefits lowering coupling and perceived costs increasing coupling. Perceived costs and benefits also had a significant effect on innovation resistance. Finally, perceived costs and benefits had a significant effect on the consumers' usage of wearable devices.

Influence of a silane coupling agent on the optoelectrical properties of carbon nanotube/binder hybrid thin films

  • Han, Joong-Tark;Woo, Jong-Seok;Jeong, Hee-Jin;Jeong, Seung-Yol;Lee, Geon-Woong
    • Carbon letters
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    • 제12권2호
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    • pp.90-94
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    • 2011
  • We present the effect of a coupling agent on the optoelectrical properties of few-walled carbon nanotube (FWCNT)/epoxy resin hybrid films fabricated on glass substrates. The FWCNT/epoxy resin mixture solution was successfully prepared by the direct mixing of a $HNO_3$-treated FWCNT solution and epoxy resin. FWCNT/binder hybrid films containing different amounts of the coupling agent were then fabricated on UV-ozone-treated glass substrates. To determine the critical binder content ($X_c$), the effects of varying the binder content in the FWCNT/silane hybrid films on their optoelectrical properties were investigated. In this system, the $X_c$ value was approximately 75 wt%. It was found that above $X_c$, the coupling agent effectively decreased the sheet resistance of the films. From microscopy images, it was observed that by adding the coupling agent, more uniform FWCNT/binder films were formed.

개구부 신설에 따른 병렬 전단벽의 거동특성 (Behavior of Coupling Shear Wall with New Openings)

  • 최현기;최윤철;최창식
    • 한국구조물진단유지관리공학회 논문집
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    • 제12권5호
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    • pp.152-160
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    • 2008
  • 벽식 구조 형식의 아파트는 횡력에 저항하는 주요 부재로 내력벽을 사용하기 때문에 내력벽에 개구부를 설치함으로써 발생하는 단면손실로 인한 내력 손실은 구조물 전체에 심각한 문제를 발생시킬 수도 있다. 또한 개구부 설치에 따라 발생되는 연결보(개구부 상부의 인방)및 연결 슬래브(인방이 없을 경우)에 대한 평가는 미흡한 실정이다. 이에 본 연구에서는 개구부를 설치한 전단벽의 연결부재에 따른 벽체의 거동특성을 알아보고자 1/2 축소된 2층 독립 전단벽체를 계획하였다. 실험결과 개구부 설치에 따른 유효 단면 감소에 의한 내력 감소가 나타났으며, 강성, 에너지 소산능력 등에 있어 연결부재인 연결보와 연결슬래브에 따라 차이를 보였다.

철근콘크리트 기둥과 철골 보의 접합부 형식 발전 및 용접성능에 관한 시험적 연구 (A Study on the Improvement and Test on Welding Performance of R/C Column-Steel Girder Connection)

  • 최광호;이세웅;김재순;김상식
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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    • pp.569-574
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    • 1997
  • This research has improved composite joint system of R/C column and steel beam developed at previous study. In this system, the shear force occurred at beam is transmitted by bearing resistance of stiffness and moment is resisted by tension capacity of coupling members. As the preliminary step of stress transfer tests of this system, welding performance test of coupling member such as round bar or square bar which has a role of moment transfer has been carried out. From the test, this element has a good welding performance and enough resistance capacity compared to design force.

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NiO/NiFe/Cu/NiFe 스핀-밸브 샌드위치의 자기저항 특성 (Magneto resistance in NiO/NiFe/Cu/NiFe spin-valve Sandwiches)

  • 김재욱
    • E2M - 전기 전자와 첨단 소재
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    • 제10권10호
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    • pp.1016-1021
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    • 1997
  • Magneto resistance properties in spin-valve sandwiches with various thickness of nanmagnetic layer in contact with the ferromagnetic NiFe film were investigated. The NiFe layer in contact with the NiO film was pinned by strongly exchange-biased coupling and the free NiFe layer at the film surface induced a sharp change in the magnetoresistance at -5~15Oe due to small coercivity. The NiO/NiFe/Cu/NiFe film showed a magnetoresistance ratio in the range of 2.3~2.9% and a field sensitivity above 2.2%/Oe with various of nonmagnetic layer. The NiO/NiFe/Cu/NiFe film of the field sensitivity above 2.2%/Oe suggests stang possibility of magnetic sensor matter.

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대규모 그리드 접지전극의 과도접지임피던스의 측정 (The transient grounding impedance measurment of large grid grounding electrodes)

  • 전병욱;이수봉;이봉;이승주;정동철;이복희
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2008년도 추계학술대회 논문집
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    • pp.69-72
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    • 2008
  • This paper presents the transient and conventional grounding impedance behaviors of large grid grounding system associated with the injection point of impulse current The measurement methods consider two possible errors in the grounding-system impedances: (1) ground mutual resistance due to current flow through ground from the ground electrode to be measured to the current auxiliary, (2) ac mutual coupling between the current test lead and the potential test lead The test circuit was set to reduce the error factors. The transient grounding impedance depends on the rise time and injection point of impulse current It is effective that grounding conductor is connected to the center of the large grid grounding system.

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유도전동기 서보운전을 위한 마이크로프로세서-벡터 제어 시스템 (Microprocessor-Based Vector Control System for Induction Motor Servo- Drive)

  • 김광헌;김영렬;원충연;원종수
    • 대한전기학회논문지
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    • 제40권12호
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    • pp.1218-1229
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    • 1991
  • The time optimal position control design can be repeatedly taken from the initial state of a dynamic system to a desired one as fast as possible in the industrial drives. In this case, an induction machine parameters will vary due to temperature, frequency, and saturation effects. In particular, the rotor resistance changes critically with temperature and frequency. These changes affect the command values of the stator current components and slip speed. There is a mismatch between the commanded variables and actual ones of the induction motor drive, and this situation leads to coupling of the vector controller from the plant, i.e. the induction motor . Consequences of such a coupling include the initiation of oscillations of the rotor flux and unsuitable switching of electromagnetic torque for the induction motor servo drive. Therefore, this paper describes a rotor resistance parameter compensating method for the induction motor, And the validity of the proposed design method is confirmed by simulation studies and experiment results.

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손실결합 공동공진기의 간편한 Q 측정 방법 (A simple Q measurement method of a lossy coupled cavity resonator)

  • 한대현
    • 한국정보통신학회논문지
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    • 제22권7호
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    • pp.1015-1020
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    • 2018
  • 공동공진기는 마이크로파 응용에서 많이 사용되는 부품 중의 하나이다. 무부하 Q, 공진주파수, 그리고 결합계수는 공진기 기본 파라미터이다. 손실결합이 있는 공동공진기의 무부하 Q를 측정하는 간편한 절차를 제안하였다. 공진주파수 근처 주파수 대역에서 결합손실을 포함한 등가회로를 보였으며, 결합손실은 공진기의 임피던스를 측정하여 구했다. 결합손실을 보상한 공진기의 임피던스를 스미스차트에 다시 그렸다. 보상한 임피던스 궤적에서 부하 Q와 결합계수를 구하여 무부하 Q를 계산하였다. 제안한 절차를 검증하기 위하여 결합 손실이 없는 공진기를 측정하였다. 결합 손실이 있는 경우와 손실이 없는 경우의 측정결과는 잘 일치 하였다. 측정된 결과는 제안한 절차가 유용함을 확인하였다.