• Title/Summary/Keyword: Carrier

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DIRECT PROBING OF CARRIER MOTION IN ORGANIC FIELD EFFECT TRANSISTOR BY OPTICAL SECOND HARMONIC GENERATION

  • Iwamoto, Mitsumasa;Manaka, Takaaki;Lim, Eun-Ju
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1561-1563
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    • 2008
  • We report an optical second harmonic generation measurement that allows direct probing of dynamical carrier motion in organic field effect transistors. Carrier injection and transport process are discriminated. The mobility and contact resistance of pentacene FETs are determined from the visualized diffusion-like carrier motion.

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A study on the thermal characteristics of MOSS type LNG carrier (MOSS형 LNG 선박의 열공학적 특성에 관한 연구)

  • 이세동;송성옥;이종원;김춘식;최두열
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.1
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    • pp.28-34
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    • 1998
  • This paper introduced the thermal characteristics of Moss Rosenberg Verft spherical tank type LNG Carrier. Especially described the temperature variation during cooling down condition. It is not easy task to calculate the temperature variation because of unsteady state condition. In this paper, computer simulation program is developed by using a Tomas Algorithm on unsteady state condition and compared with calculation results and experimental results on existing LNG Carrier voyage.

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An Improved Saw Tooth Carrier PWM Method for Three Phase Voltage Source Inverters (3상 전압원 인버터를 위한 개선된 톱니 반송파 펄스 폭 변조 방법)

  • Park, In-Gyu
    • Proceedings of the KIEE Conference
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    • 1995.11a
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    • pp.302-305
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    • 1995
  • An improved carrier PWM method for three phase voltage source inverters is proposed. The basic idea of the proposed method is deleting unnecessary 1/3 of switchings in the saw tooth carrier PWM method. The lowest frequency of the remained harmonics of this method (when the modulation index is large) is about 50% higher and the maximum modulated voltage is about 15% higher than those of the triangular carrier PWM method. This method will be useful especially in the linear feedback current control and MOSFET inverters.

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Development of Cargo Working Education System for LNG Carrier (LNG선 하역작업 교육 시스템 개발에 관한 연구)

  • Kim, Dae-Hee;Yea, Byeong-Deok;Song, Chae-Uk
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.06a
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    • pp.1041-1046
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    • 2005
  • This paper describes a system for LNG carrier's loading and discharging work education. This system consists of three modules(cargo work simulation, ballast work simulation and loading calculation module), and could be a useful to train mariners boarding on LNG carrier so as to take a suitable action while their ship maneuvering and cargo handling.

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Relationship Between GPS Code and Carrier Tracking Performance for GPS Receivers (GPS 수신기에서 코드 추적 성능와 반송파 추적 성능의 관계)

  • 임영재;박찬식
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.56-56
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    • 2000
  • In this paper, the relationship between GPS code and carrier tracking performance is given. Through the error analysis and experiments, the performance of code tracking loop can be improved using narrow correlation. The performance of code tracking loop can be also improved if the better carrier tracking loop is used. On the other hand, the performance of carrier tracking loop is independent of that of code tracking loop.

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Performance Analysis of Least-Squares Estimation and LAMBDA Method for GPS Precise Positioning using Carrier Phase (GPS 반송파 위상을 이용한 정밀 측위의 최소자승법과 LAMBDA기법의 성능분석)

  • 박헌준;원종훈;고선준;이자성
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.146-146
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    • 2000
  • This paper presents field test results of the GPS precise positioning using carrier phase observable. The Least-squares AMBiguity Decorrelation Adjustment(LAMBDA) method is implemented to resolve integer ambiguity problem for two epoch Ll carrier phase measurement data. Field test results show that the GPS precise positioning of cm-level accuracy is obtainable with conventional low cost, single frequency C/A code GPS receivers.

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A Study on the PR Shaped SQAM Performance with Carrier Phase Error (PR Shaped SQAM의 Performance에 Carrier Phase Error가 미치는 영향에 관한 연구)

  • 박용우;이형재
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1983.10a
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    • pp.97-101
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    • 1983
  • A Study is presented showing the effect of carrier phase error on the error-rate of a PR shaped SQAM digital radio system. A simple upper bound on the probability of error as a function of phase error is derived and compared to one another. The result is that if carrier phase error is less than 3 there is no serious degradation.

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Evaluation of Korean Mail Carrier Uniforms for Improvement of Essential Aspects (한국 집배원 유니폼의 개선요소 분석)

  • Jeon, Kyung-Ae
    • Fashion & Textile Research Journal
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    • v.5 no.3
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    • pp.221-226
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    • 2003
  • This study evaluates the problems with various aspects of Korean mail carrier uniforms. It is sponsored by the as part of a 2002 research project. This research project is 'A study on mail collection and delivery environment based on ergonomics'. One of the most urgent tasks to create a better work environment is improvement of mail carrier uniforms. Improved uniforms will result in improved job performance and satisfaction.

A Study on the Automatic Inspection System for Flat Panel Display GLASS Carrier (FPD GLASS Carrier를 위한 자동 검사 시스템에 관한 연구)

  • Kim, Hyo-Nam
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2014.01a
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    • pp.399-400
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    • 2014
  • 최근에 디스플레이 산업이 변화하고 우리나라 기업들이 세계시장을 주도해나가고 있는 실정이다. 특히 FPD 기술에 있어서 화면의 크기가 급속하게 대형화함에 따라 품질향상과 생산성 향상을 위해서 생상환경과 설비의 자동화가 매우 중요한 이슈가 되고 있다. 본 논문에서는 FPD 제조 공정 중 화학 증착 및 메탈 주입 공정 중 원판 GLASS의 이송 및 고정에 있어 항시 사용하는 GLASS CARRIER의 검사에 있어서 자동으로 검사할 수 있는 시스템을 제안한다.

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Performance Analysis of Multi-Carrier CDMA Trellis Coded 16 QAM System with Near/Far Effect in Frequency Selective Multipath Fading Channel (주파수 선택성 다중경로 페이딩 채널에서 Near/Far 영향을 받는 Multi-Carrier CDMA Trellis Coded 16 QAM 시스템의 성능해석)

  • 노재성;강희조;김춘길;김언곤;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.3A
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    • pp.352-361
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    • 2000
  • The performance of a multi-carrier CDMA system is analyzed considering frequency selective multipath fading and Near/Far effects. The number of multicarrier, multiuser, and arms of RAKE receiver, and the decay ratio of frequency selective multipath fading are used as a parameter for the performance analysis. More over, the distribution and the strength of multiuser interference are also considered. To evaluate the Near/Far effects in a multi-carrier CDMA system, three distribution models are assumed. In the first model, interference to carrier Ratio, I/C, ranges from -4 dB to 4dB, and at each 2 dB interval, 20 % of multiuser is assumed to be uniformly distributed. In the second one, I/C ranges from -2 dB to 2 dB, and 33.3% of multiuser is assumed to be equally dispersed at each 2dB interval. The third model is 0 dB of I/C, that is, with perfect power control, multiuser are assumed to be evenly located. In this paper, multi-carrier CDMA system adoption RAKE receiver is proposed to mitigate the frequency selective multipath fading. From the results, the third model(i.e. perfect power control) shows the best performance, and the narrower range of I/C causes the less effects to the desired signal, which reads to the better performance.

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