• 제목/요약/키워드: Hall studies

검색결과 200건 처리시간 0.025초

Magneto-optical Measurements of Semiconductor Quantum Structures in Pulsed-magnetic Fields

  • Kim, Yongmin
    • Applied Science and Convergence Technology
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    • 제23권1호
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    • pp.1-13
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    • 2014
  • Semiconductor quantum structures are often characterized by their energy gaps which are modified by the quantum size effect. Energy levels in semiconductors can be realized by optical transitions within confined structures. Photoluminescence spectroscopy in magnetic fields at low temperatures has proved to be a powerful technique for investigating the electronic states of quantum semiconductor heterostructures and offers a complimentary tool to electrical transport studies. In this review, we examine comprehensive investigations of magneto-excitonic and Landau transitions in a large variety of undoped and doped quantum-well structures. Strong magnetic fields change the diamagnetic energy shift of free excitons from quadratic to linear in B in undoped single quantum well samples. Two-dimensional electron gas induced by modulation doping shows pronounce quantum oscillations in integer quantum Hall regime and discontinuous transition at ${\nu}=1$. Such discontinuous transition can be explained as the formation of spin waves or Skyrmions.

항일의병기념관 계획 (A Plan Memoral Hall of loyal troops Resistance to Japan)

  • 차상기
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2007년도 추계학술발표대회 논문집
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    • pp.198-201
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    • 2007
  • Currently, both Korea and Japan have cooperated to get a foothold in economic major countries in the Asia through the various economic cooperation and the overcoming of cultural difference in cultural interchanges between two countries. However, in the present age, two countries are on the other road in historical view and conception; the final report over 3 year studies by the two countries' history study partnership commission shows the above views; while Korea has been in base of Japan colonialization's unjustification, Japan has been in base of its facts. The aboves have proved that Japan has not taken an honest self examination and conscience over the history. Accordingly, Japan resistance volunteer memorial is proposed as the educational place to carry down the martyr's holy patriotism in later ages and practice its spirit by learning the resistance volunteer resistance volunteer movement, which focused on resisting the Japan invasion and fighting the independence.

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자기스케일을 이용한 비접촉식 변위센서 (Noncontact displacement sensors using magnetic scale)

  • 이성필;서영진
    • 센서학회지
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    • 제18권3호
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    • pp.197-201
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    • 2009
  • This paper studies on the noncontact displacement sensor system to detect the displacement of the cylinder rod. For an inexpensive and a simple process, magnetic scales are printed on the cylinder rod, and magnetized by the specially designed magnetizer that has an yoke through the alternation of N and S pole. Noncontact displacement sensor system consists of cylinder with magnetic scales, Hall sensor, linear guide, controller and display. The system can detect the displacement of moving cylinder with 5 cm/sec in the case of 1 mm magnetic scale. It shows a possibility of position detection of hydraulic cylinder and air cylinder.

칼만 필터를 적용한 레졸버 위치 오차 보상기법 (Position Error Compensation Method for Resolvers using Kalman Filter)

  • 안지혜;안형진;박준열
    • 조명전기설비학회논문지
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    • 제29권5호
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    • pp.50-56
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    • 2015
  • As rotor position is a reference of coordinate in vector control of PMSM, the information of exact rotor position is required. To measure the position of motors, hall-effect sensors, encoders, resolvers, etc. are used. Among these sensors, resolvers have good endurance in the variation of circumstance and can be used in a wide range of temperature, but resolvers are less exact than encoders. In addition, resolvers have a drawback that the output signal contains periodic error components. Thus, this paper proposes a compensation method for the unique position error in resolvers using Kalman filter to achieve high performance control of PMSM. The validity of the proposed scheme is demonstrated through simulation studies.

대용량 HVDC 컨버터의 Busbar 설계 (Busbar Design of High Power HVDC Converter)

  • 김찬기;박용훈;김진영
    • 전기학회논문지
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    • 제61권7호
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    • pp.923-927
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    • 2012
  • This paper studies a busbar design of high power HVDC converter. In order to design a electrical busbar, we need to consider electrical, mechanical and environmental condition. In this papre, we focus on the electrical design in terms of temperaure and currnet. Busbar conductor can be damaged to burn due to the temperature and fault current of busbar. In this paper, Busbar design of Jindo-Jeju HVDC #2 System that will start operate in 2012 is considered.

co-sputtering법으로 제조한 Insb박막의 후열처리기술에 의한 자기저항 특성 (Properties of Magneto-resistance by annealing using by co-sputtering method)

  • 김태형;소병문;송민종;박춘배
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 제4회 영호남학술대회 논문집
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    • pp.128-132
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    • 2002
  • Many compound semiconductors which have high carrier mobility and small band gap have attentive in application of various practical a field. Especially, InSb served for Hall device and magnetic resistor such as magnetic sensor because InSb thin film has high mobility. Many studies on InSb thin film deposistion because In and Sb has been very different feature of vapor pressure($10^{-4}$ times) When In and. Sb deposited. In this paper studied it In and Sb deposited simultaneously using by method of co-sputtering deposotion. This process, get to effects of manufacture process simplification. After that this paper observed micro structure and electronic behavior of InSb thin film using by co-sputtering and we study properties of magneto-resistance by annealing

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Social Construction of Mathematics Understanding among Student Peers in Small Group Settings

  • Cho, Cheong-Soo
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제3권2호
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    • pp.89-98
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    • 1999
  • The purpose of this review of literature is to investigate what kinds of research have been done on social construction of mathematics understanding among elementary students in small groups. Only empirical studies were reviewed, and then grouping was done in terms of the purpose of the study. This grouping identified three categories: 1) Social and mathematical norms in mathematics classroom, 2) Teaching productive communication behaviors for active learning in small group, and 3) Participation roles and communication behaviors in different group structure. To enhance social construction of mathematics understanding in small group settings two suggestions are made: the importance of the selection of collaborative tasks or problems and teachers' beliefs about mathematics and the teaching an learning of mathematics.

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Overview on Peroxiredoxin

  • Rhee, Sue Goo
    • Molecules and Cells
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    • 제39권1호
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    • pp.1-5
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    • 2016
  • Peroxiredoxins (Prxs) are a very large and highly conserved family of peroxidases that reduce peroxides, with a conserved cysteine residue, designated the "peroxidatic" Cys ($C_P$) serving as the site of oxidation by peroxides (Hall et al., 2011; Rhee et al., 2012). Peroxides oxidize the $C_P$-SH to cysteine sulfenic acid ($C_P$-SOH), which then reacts with another cysteine residue, named the "resolving" Cys ($C_R$) to form a disulfide that is subsequently reduced by an appropriate electron donor to complete a catalytic cycle. This overview summarizes the status of studies on Prxs and relates the following 10 minireviews.

Numerical Study of Low-Power MPD Arcjet

  • Funaki, Ikkoh;Kubota, Kenichi;Okuno, Yoshihiro;Sato, Hiroki;Fujino, Takayasu
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년 영문 학술대회
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    • pp.570-573
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    • 2008
  • In spite of many experimental studies of low-power applied-field magnetoplasmadynamic(AFMPD) thrusters, thrust efficiencies of the past thrusters are very low. Hence, drastic improvement in thrust performance is required for AF-MPD thrusters to compete against other types of electric propulsion in a moderate power regime around 10 kW. For the optimization of AF-MPD thrusters, a numerical code for the flowfield simulation is now under development. A preliminary result shows that the code can deal with a complicated mixture of the induced and applied magnetic fields, which will lead to a combination of the self-field, swirl, Hall, as well as electrothermal accelerations.

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한국의 비판언론학에 대한 비판적 성찰: 문화연구와 정치경제학을 중심으로 (A Critical Review on the Critical Communication Studies in Korea)

  • 조항제
    • 한국언론정보학보
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    • 제43권
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    • pp.7-46
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    • 2008
  • 이 글의 목적은 문화연구와 정치경제학을 중심으로 한국의 비판언론학을 성찰하고 미래의 방향을 제시보고자 하는 데 있다. 1980년대 중후반부터 나타나기 시작한 문화연구의 '소비로의 전환'은 문화연구를 신수정주의로 부르게 만든 결정적인 요소의 하나지만, 한국에서는 비판적 문제의식의 단절로 읽혀져 문화연구에 대한 끊임없는 정체성 논란을 불러일으켰다. 그러나 정작 정치경제학은 자신이 중시하는 생산(과정)/구조에 대해서도 많은 연구를 내지 못했고, 문화연구 역시 이 부문에서는 무관심으로 대응했다. 국면주의는 문화연구가 현실에 개입하는 유력한 방식이지만 초기의 연구 외에는 후속연구가 그다지 활발하지 못해 이론화 수준이 높지 않고, 한국에서의 연구 또한 아직은 많은 논란을 안고 있어 성과 여부가 불투명하다. 비판연구가 가진 저항성의 문제는 운동론에서 두드러지는데, 이 글에서는 문화연구의 특징이 잘 배어 있는 소수자문화운동론에 대한 검토를 통해 사회적 배치의 여전한 중요성을 강조했다. 미래의 방향에서는 일부 논자들이 제안한 바 있는 문화연구와 정치경제학의 화합 가능성을 긍정적으로 검토했고, 이의 근저에 있는 근대주의/탈근대주의 합의의 가능성과 필요성 역시 차이를 인정하면서도 결합의 가능성도 놓치지 않는 '복합적 합의'를 하나의 대안으로 제시했다. 마지막으로 '시공간의 재조직', '소비자본주의', '문화적 시민권'(또는 '문화적 공론장'), '생산문화', '시민/소비자', '차별화/차이', '공영방송의 미래' 등을 양측이 서로 경(결)합할 수 있는 공감대가 큰 연구주제로 꼽았다.

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