• Title/Summary/Keyword: 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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    • v.7 no.1
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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.

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

  • Lee, Chaehui;Jeong, Hyunsoo;Park, Kyu-Chil;Park, Jihyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.3
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    • pp.436-442
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    • 2022
  • In this paper, the performance of the selective combining according to the channel selection decision method of frequency diversity is evaluated in the underwater frequency selective channel. The underwater acoustic channel in the shallow sea has a complex multipath characteristic by combining various environmental factors such as boundary surface reflection and sound wave refraction according to the water temperature layer. In particular, frequency selectivity due to multipath causes energy fluctuation in a communication channel, which reduces SNR (Signal to Noise Ratio) and deteriorates communication performance. In this paper, we applied the frequency diversity technique using multiple channels to secure the communication performance according to the frequency selectivity by multipath. For each channel, 4-FSK (Frequency Shift Keying) and selective combining were applied, the performance was evaluated by applying the maximum value, average value, and majority decision of the signal in order to decide the demodulation channel selection of the selective combining.

가교된 PVA/PAA막을 이용한 물-페놀 계의 투과증발 분리

  • 임지원;손민영;이규호
    • Proceedings of the Membrane Society of Korea Conference
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    • 1992.04a
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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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A High-Speed Dual-Modulus Prescaler Using Selective Latch Technique (Selective Latch Technique을 이용한 고속의 Dual-Modulus Prescaler)

  • 김세엽;이순섭김수원
    • Proceedings of the IEEK Conference
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    • 1998.10a
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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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A Study on the Validity of the Selective Arbitration Clause on Construction Arbitration (건설중재에 있어서 선택적중재합의의 유효성에 관한 연구)

  • Suh, Jeong-Il
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.25
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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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Delay Analysis of Selective Repeat ARQ for a Markovian Source Over a Wireless Channel (무선 채널에서의 Selective Repeat ARQ 프로토콜의 Delay 성능 분석)

  • Kim Jeong Geun;Kim Young Soo;Lee Kyesan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.11B
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    • pp.930-937
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    • 2004
  • In this paper, we analyze the delay performance for a Markovian source transported over a wireless channel with time-varying error characteristics. To improve the reliability of the channel, the end points of the wireless link implement a selective-repeat (SR) ARQ error control protocol. We provide an approximate discrete-time analysis of the end-to-end mean packet delay, which consists of transport and resequencing delays. Numerical results and simulations indicate that our approximate analysis is sufficiently accurate for a wide range of parameter values.

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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    • v.20 no.1
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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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Robotic Lateral Compartment Selective Neck Dissection in Well-Differentiated Thyroid Carcinoma (갑상선 분화암에서 로봇을 이용한 측경부 림프절 절제술)

  • Tae, Kyung
    • Korean Journal of Bronchoesophagology
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    • v.17 no.2
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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
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.7A
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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