• 제목/요약/키워드: selective

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Hole Selective Contacts: A Brief Overview

  • Sanyal, Simpy;Dutta, Subhajit;Ju, Minkyu;Mallem, Kumar;Panchanan, Swagata;Cho, Eun-chel;Cho, Young Hyun;Yi, Junsin
    • Current Photovoltaic Research
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    • 제7권1호
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    • pp.9-14
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    • 2019
  • Carrier selective solar cell structure has allured curiosity of photovoltaic researchers due to the use of wide band gap transition metal oxide (TMO). Distinctive p/n-type character, broad range of work functions (2 to 7 eV) and risk free fabrication of TMO has evolved new concept of heterojunction intrinsic thin layer (HIT) solar cell employing carrier selective layers such as $MoO_x$, $WO_x$, $V_2O_5$ and $TiO_2$ replacing the doped a-Si layers on either front side or back side. The p/n-doped hydrogenated amorphous silicon (a-Si:H) layers are deposited by Plasma-Enhanced Chemical Vapor Deposition (PECVD), which includes the flammable and toxic boron/phosphorous gas precursors. Due to this, carrier selective TMO is gaining popularity as analternative risk-free material in place of conventional a-Si:H. In this work hole selective materials such as $MoO_x$, $WO_x$ and $V_2O_5$has been investigated. Recently $MoO_x$, $WO_x$ & $V_2O_5$ hetero-structures showed conversion efficiency of 22.5%, 12.6% & 15.7% respectively at temperature below $200^{\circ}C$. In this work a concise review on few important aspects of the hole selective material solar cell such as historical developments, device structure, fabrication, factors effecting cell performance and dependency on temperature has been reported.

수중 주파수 선택적 채널에서 주파수 다이버시티의 채널 선택 판정법에 따른 선택 합성법의 성능 (Performance of selective combining according to channel selection decision method of frequency diversity in underwater frequency selective channel)

  • 이채희;정현수;박규칠;박지현
    • 한국정보통신학회논문지
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    • 제26권3호
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    • pp.436-442
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    • 2022
  • 본 논문은 수중 주파수 선택적 채널에서 주파수 다이버시티의 채널 선택 판정법에 따른 선택 합성법 (selective combining)의 성능을 평가하였다. 천해 수중 음향 채널은 경계면 반사와 수온 층에 따른 음파 굴절 등의 다양한 환경요인이 결합하여 복잡한 다중경로의 특성을 가진다. 특히, 다중경로에 의한 주파수 선택성 (frequency selectivity)는 통신 채널의 에너지 변동을 발생시키고, 이로 인해 SNR (Signal to Noise Ratio)가 감소하여 통신성능이 저하된다. 본 논문에서는 다중경로의 주파수 선택성에 따른 통신성능 확보를 위해 다수의 채널을 이용하는 주파수 다이버시티 기법을 적용하였다. 각 채널은 4-FSK (Frequency Shift Keying)과 선택 합성법을 적용하였으며, 선택 합성법의 복조 채널 선택 판정을 위해 신호의 최댓값, 평균값 그리고 심벌 비교 판정 (majority decision)을 적용하여 성능을 평가하였다.

가교된 PVA/PAA막을 이용한 물-페놀 계의 투과증발 분리

  • 임지원;손민영;이규호
    • 한국막학회:학술대회논문집
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    • 한국막학회 1992년도 춘계 총회 및 학술발표회
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    • pp.58-59
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    • 1992
  • 투과 증발법에 의한 유기 성분을 포함하는 물의 농축은 일반적으로 water-selective와 organic-selective인 2개의 투과 증발 장치를 연결하여 사용되어지며 이때 organic permeate는 재순환되고 그리고 organic retentate는 회수되어지며, water retentate는 다른 곳에 사용된다. 본 논문에서는 이중 두번째 단계인 water- selective 막을 이용한 투과 증발 분리에 대해 조사하였다.

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Selective Latch Technique을 이용한 고속의 Dual-Modulus Prescaler (A High-Speed Dual-Modulus Prescaler Using Selective Latch Technique)

  • 김세엽;이순섭김수원
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 추계종합학술대회 논문집
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    • pp.779-782
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    • 1998
  • This paper describes a high-speed Dual-modulus Prescaler (DMP) for RF mobile communication systems with pulse remover using selective latch technique. This circuit achieves high speed and low power consumption by reducing full speed flip-flops and using a selective latch. The proposed DMP consists of only one full speed flip-flop, a selective latch, conventional flip-flops, and a control gate. In order to ensure the timing of control signal, duty cycle problem and propagation delay must be considered. The failling edgetriggered flip-flops alleviate the duty cycle problem andthis paper shows that the propagation delay of control signal doesn't matter. The maximum operating frequency of the proposed DMP with 0.6um CMOS technology is up to 2.2㎓ at 3.3V power supply and the circuit consumes 5.24mA.

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건설중재에 있어서 선택적중재합의의 유효성에 관한 연구 (A Study on the Validity of the Selective Arbitration Clause on Construction Arbitration)

  • 서정일
    • 무역상무연구
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    • 제25권
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    • pp.165-187
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    • 2005
  • Arbitration is a creature of contract. The parties agree that selective dispute resolution clause provides them with a choice to litigate or arbitrate certain disputes. Under the agreements, the parties had the option in the action. In the event any dispute arises between the parties concerning our representation or payment of our fees and disbursements which cannot be promptly resolved to our mutual satisfaction, you agree that dispute will be submitted to arbitration. Arbitration is a matter of contract and a party cannot be required to submit to arbitration any dispute which he has not agreed so to submit. The selective arbitration agreement has become an accepted method of dispute resolution. However, the trend of dispute settlement has changed. The selective arbitrations clauses are to be construed as broadly as possible, and arbitration will be compelled unless it may be said with positive assurance that arbitration clause is not susceptible of an interpretation that covers the asserted dispute.

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무선 채널에서의 Selective Repeat ARQ 프로토콜의 Delay 성능 분석 (Delay Analysis of Selective Repeat ARQ for a Markovian Source Over a Wireless Channel)

  • 김정근;김영수;이계산
    • 한국통신학회논문지
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    • 제29권11B
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    • pp.930-937
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    • 2004
  • 이 논문에서는 시간에 따라 채널 상태가 변화는 무선 채널 상에서 Markov 소스의 딜레이 성능을 분석하였다. 무선 링크의 양단에서 Selective-repeat (SR) ARQ 프로토콜을 사용한다고 가정했다. 이 논문에서는 대기 시간과 전송 및 재전송 시간 그리고 재 정렬 시간으로 구성된 단대단 평균 패킷 딜레이에 대한 근사화된 분석 방식을 제안하였다. 수치적인 분석과 시뮬레이tus 결과와의 분석을 통해서, 이 연구에서 제안한 분석 방식이 대부분의 경우 정확한 결과를 예측하고 있음을 증명하였다.

Optimal Immobilization of Penicillinase for Ion-selective Electrode

  • Hur, Moon-Hye;Kang, Hee-Jin;Min, Hye-Young;Lee, Ji-Yeun;Lee, Ki-Hyun;Ahn, Moon-Kyu
    • Archives of Pharmacal Research
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    • 제20권1호
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    • pp.68-71
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    • 1997
  • Penicillin sensor was prepared by immobilizing penicillinase (Pcase) on $H^{+}$-selective carboxylated poly (vinyl chloride) (PVC-COOH) membrane or cellulose filter membrane. The immobilization techniques are as follows. Pcase was immobilized with GTH on $H^{+}$-selective PVC-COOH membrane or some amount of BSA was dropped on that membrane. Another method to make immobilization is to mix type I Pcase with GTH and drop on a cellulose filter membrane. According to immobilization techniques, there were some differences in response properties of enzyme electrodes, however, all electrodes responded to Pcase-resistant penicillin derivatives. Pcase immobilized on cellulose filter membrane with $H^{+}$-selective PVC membrane eletrode was more stable and more sensitive to penicillinase-resistant penicillin derivatives than any other immobilization techniques.

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갑상선 분화암에서 로봇을 이용한 측경부 림프절 절제술 (Robotic Lateral Compartment Selective Neck Dissection in Well-Differentiated Thyroid Carcinoma)

  • 태경
    • 대한기관식도과학회지
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    • 제17권2호
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    • pp.83-88
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    • 2011
  • Robotic thyroidectomy has been developed to minimize neck scarring, and several authors have described its feasibility and safety, and have reported surgical outcomes comparable with conventional open thyroidectomy. The da Vinci surgical system robot provides a three-dimensional $10-12{\times}$magnified view of the surgical area. It also provides hand-tremor filtration, fine motion scaling, and precise and multi-articulated hand-like motions. Recently, robotic technology has also been applied to lateral compartment neck dissection in thyroid cancer. We have developed a new novel selective neck dissection procedure by a gasless unilateral axillo-breast (GUAB) approach with a da Vinci Surgical System for well-differentiated thyroid carcinoma to avoid a long visible neck scar. Based on our early experience, robotic selective neck dissection by GUAB approach is a safe, feasible and cosmetically excellent procedure. It can be an alternative to conventional open surgery in the highly selected patients with well-differentiated thyroid carcinoma. The oncologic safety of robotic selective neck dissection should be verified with long-term follow-up data.

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On Maximum Diversity Order over Doubly-Selective MIMO-OFDM Channes

  • Yang Qinghai;Kwak Kyung Sup
    • 한국통신학회논문지
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    • 제30권7A호
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    • pp.628-638
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    • 2005
  • The analysis of maximum diversity order and coding gain for multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems over time-and frequency-selective (or doubly-selective) channels is addressed in this paper. A novel channel time-space correlation function is developed given the spatially correlated doubly-selective Rayleigh fading channel model. Based on this channel-model assumption, the upper-bound of pairwise error probability (PEP) for MIMO-OFDM systems is derived under the maximum likelihood (ML) detection. For a certain space-frequency code, we quantify the maximum diversity order and deduce the expression of coding gain. In this wort the impact of channel time selectivity is especially studied and a new definition of time diversity is illustrated correspondingly