• 제목/요약/키워드: The carrier

검색결과 6,836건 처리시간 0.029초

통계적 기법을 이용한 선택적 CVD 텅스텐 공정 최적화 연구 (The Optimization of the Selective CVD Tungsten Process using Statistical Methodology)

  • 황성보;최경근;박흥락;고철기
    • 전자공학회논문지A
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    • 제30A권12호
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    • pp.69-76
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    • 1993
  • The statistical methodology using RSM (response surface method) was used too ptimize the deposition conditions of selective CVD tungsten process for improving the deposition rate and the adhesion property. Temperature, flow rate of SiH$_4$ and WF$_6$ and H$_2$ and Ar carrier gases were chosen for the deposition variables and process characteristics due to carrier gas were intensively investigated. It was observed that temperature was the main factor influencingthe deposition rate in the case of H$_2$ carrier gas while the reactant ratio, $SiH_{4}/WF_{6}$, had the principal effect on the deposition rate in the case of Ar carrier gas. The increased deposition rate and the good adhesion to Si were obtained under Ar carrier gas compared to H$_2$ carrier gas. The optimum conditions for deposition rate and antipeeling property were found to be the temperature range of 300~32$0^{\circ}C$ and the reactant ratio, $SiH_{4}/WF_{6}$, of 0.5~0.6.

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위성방송용 QPSK 복조기를 위한 DPLL구조의 Carrier Recovery Loop 설계 (Design of Carrier Recovery Loop in DPLL Structure for QPSK Demodulator Satellite Broadcasting)

  • 하창우;이완범;김형균;김환용
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
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    • pp.165-168
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    • 2001
  • In this W the complexity of implementation is reduced by the reduction into half of the number of the multiplier in filter structure of the conventional carrier recovery loop, and as the drawback of NCO of the conventional carrier recovery loop wastes a amount of power for the structure of lookup table, We designed the structure of combinational logic without the lookup table. In the comparison with dynamic power of the proposed NCO, the power of NCO with the lookup table is 175${\mu}$W, NCO with the proposed of structure is 24,65${\mu}$W. As if result, it is recognized that about one eight of loss power is reduced In the simulation of carrier recovery loop designed QPSK demodulator, it is known that the carrier phase is compensated.

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중국해상법상의 해상물건운송 중 실제운송인에 관한 연구 (A Study on the Actual Carrier in Carriage of Goods by Sea in Maritime Code of China)

  • 마염추
    • 한국항해학회지
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    • 제25권3호
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    • pp.269-281
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    • 2001
  • 실제운송인은 해상물건운송 법률관계의 특수한 주체이다. 함부르크 규칙은 실제운송인 제도를 설립하였다. 중국해상법은 함부르크 규칙을 참조하고 실제운송인 제도를 도입하여 제4장에서 실제운송인에 관하여 규정하고 있다. 그러나 실제운송인에 대한 법리 해설과 사법실무에는 문제가 많이 생긴다. 본 논문은 중국해상법상 실제운송인의 의의, 실제운송인의 인정, 실제운송인의 책임에 관하여 연구하고자 한다.

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Efficient Hybrid Carrier Based Space Vector Modulation for a Cascaded Multilevel Inverter

  • Govindaraju, C.;Baskaran, K.
    • Journal of Power Electronics
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    • 제10권3호
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    • pp.277-284
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    • 2010
  • This paper presents a novel hybrid carrier based space vector modulation for cascaded multilevel inverters. The proposed technique inherits the properties of carrier based space vector modulation and the fundamental frequency modulation strategy. The main characteristic of this modulation are the reduction of power loss, and improved harmonic performance. The carrier based space vector modulation algorithm is implemented with a TMS320F2407 digital signal processor. A Xilinx Complex Programmable Logic Device is used to develop the hybrid PWM control algorithm and it is integrated with a digital signal processor for hybrid carrier based space vector PWM generation. The inverter offers less weighted total harmonic distortion and it operates with equal electrostatic and electromagnetic stress among the power devices. The feasibility of the proposed technique is verified by spectral analysis, simulation, and experimental results.

단일 반송파를 이용한 비엔나 정류기의 전압 제어 (A single-carrier comparison PWM for Voltage Control of Vienna Rectifier)

  • 윤병철;김학원;조관열;임병국
    • 전력전자학회논문지
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    • 제17권2호
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    • pp.129-134
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    • 2012
  • In this paper, a new simple PWM method for Vienna rectifier is proposed. The previous SVPWM method for Vienna rectifier is very complex and difficult to implement. To solve these problems, a new single-carrier comparison PWM method for voltage control of Vienna rectifier is proposed. Because of using the only single carrier, implementation of the proposed PWM is very simple. In the proposed PWM method, carrier comparison parts of the PWM block is only changed from the 2 level PWM control block. The usefulness of the proposed PWM method is verified by the simulation and experiment.

판재 스크래치 저감을 위한 제관 라인 이송 핑거 접촉부의 설계 개선 (Design Improvement of Carrier Finger on Sheet Metal Forming Line for the Prevention of Scratch)

  • 이민;김태완
    • Tribology and Lubricants
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    • 제28권5호
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    • pp.240-245
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    • 2012
  • In this study, we developed a new carrier finger to prevent scratches in a sheet metal forming line. The developed carrier finger was designed to have a streamlined shape with a larger radius of curvature at the edges, as well as a smaller contact area. To evaluate the scratch alleviation effect, a sliding contact analysis and scratch test using the pin on a plate wear tester were conducted for both the old and new carrier fingers. The results show that, for both transverse and longitudinal movements of the strip, the newly designed carrier finger reduces both the friction and scratch depth by its streamlined shape, which decreases the pressure spike at the edge.

Carrier Tracking Loop using the Adaptive Two-Stage Kalman Filter for High Dynamic Situations

  • Kim, Kwang-Hoon;Jee, Gyu-In;Song, Jong-Hwa
    • International Journal of Control, Automation, and Systems
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    • 제6권6호
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    • pp.948-953
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    • 2008
  • In high dynamic situations, the GPS carrier tracking loop requires a wide bandwidth to track a carrier signal because the Doppler frequency changes more rapidly with time. However, a wide bandwidth allows noises within the bandwidth of the tracking loop to pass through the loop filter. As these noises are used in the numerical controlled oscillator(NCO), the carrier tracking loop of a GPS receiver shows a degraded performance in high dynamic situations. To solve this problem, an adaptive two-stage Kalman filter, which offers the NCO a less noisy phase error, can be used. This filter is based on a carrier phase dynamic model and can adapt to an incomplete dynamic model and a quickly changed Doppler frequency. The performance of the proposed tracking loop is verified by several simulations.

저가항공 관련 국내학술지 네트워크 텍스트 분석 (Bibliometric Network Analysis on Low Cost Carrier Research)

  • 나진성;최동현
    • 한국항공운항학회지
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    • 제23권1호
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    • pp.14-23
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    • 2015
  • This study applied the network text analysis to reveal the scope and trends of low cost carrier studies. We analyzed low cost carrier research published in Korean journals and news articles. The results showed that there are three clusters in terms of research topics. First dimension consists of articles investigating growth in the low cost carrier industry. The second dimension is associated with service characteristics. The last dimension has strong ties organizational and human resource dimension. We run Krkwic, Krtitle, Netdraw, and Ucinet 6.0 to conduct the network text analysis. This study suggests the direction of low cost carrier research in the future.

p-채널 Poly-Si TFT s 소자의 Hot-Carrier 효과에 관한 연구 (A Study on the Hot-Carrier Effects of p-Channel Poly-Si TFT s)

  • 진교원;박태성;백희원;이진민;조봉희;김영호
    • 한국전기전자재료학회논문지
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    • 제11권9호
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    • pp.683-686
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    • 1998
  • Hot carrier effects as a function of bias stress time and bias stress consitions were syste-matically investigated in p-channel poly-Si TFT s fabricated on the quartz substrate. The device degradation was observed for the negative bias stress, while improvement of electrical characteristic except for subthreshold slope was observed for the positive bias stress. It was found that these results were related to the hot-carrier injection into the gate oxide and interface states at the poly-Si/$SiO_2$interface rather than defects states generation within the poly-Si active layer under bias stress.

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Polyolefin용 수성 Gravure Ink의 인쇄작성 (Printability of an Aqueous Gravure Ink for Polyolefin)

  • 김종원
    • 한국인쇄학회지
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    • 제12권1호
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    • pp.1.1-11
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    • 1994
  • The photosensitive properties and carrier transport in the organic photoconductor with the carrier transport layers(CTL) of polymer matrix doped with two carrier transport materials above carrier generation layer(CGL) containing oxotitanium phthalocyanine (TiOPc) were investigated. The CGL of TiOPc dispersed in poly(vinylbutyral) was formed as thickness of 0.1${\mu}{\textrm}{m}$and the carrier transport layer was prepared by coating polycarbonate and polyester doped with oxadiazoly(OXD), polyvinylcarbazole (PVK), trinitro fluorenone(TNF) as thickness of 10~15${\mu}{\textrm}{m}$, respectively. We have measured half decay exposure,sensitivity and xerographic gain from the photo-induced discharge curve(PIDC). In this work, it was found that the characteristics of carrier transport were mainly caused by the ionization potential difference of constitutive materials in molecularly doped polymer.

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