• Title/Summary/Keyword: Quasi-state

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Optimized design of the multimode interferenced-polarization splitter with a photodefinable polyimide (감광성 폴리이미드 재료를 가정한 다중모드 간섭 편광분리 소자의 최적설계)

  • Hong, Jung-Moo;Ryoo, Hyun-Ho;Jeong, Jae-Wan;Lee, Seung-Gol;Lee, El-Hang;Park, Se-Geun;O, Beom-Hoan;Woo, Deok-Ha;Kim, Sun-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.04b
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    • pp.101-104
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    • 2002
  • The beam splitter is important in optical communication systems. in this work, thc quasi-state based on four-mode interference in thc MMI coupler is proposed, and so, device length is shorten to be 1/5 of general designed length. We designed thc polarization splitter based on thc concept of quasi-state. Thc analysis has been accomplished by thc effective index method(EIM) and thc mode propagation analysis(MPA) for given structure.

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A family of Continuous Conduction Mode with Quasi Steady State Approach based on the General Pulse Width Modulator

  • Ala Eldin Abdallah;Khalifa Eltayed
    • Proceedings of the IEEK Conference
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    • 2002.06b
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    • pp.369-372
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    • 2002
  • This paper presents a family of continuous conduction mode with constant-switching pulse width modulator controllers. Unified implementation of quasi steady state approach for various DC-DC converters topoiogies is illustrated. The property and control low for quasi-state approach will be discussed in this paper. The different procedures will be discussed in details with different results for five commonly used DC-DC converters. Both trailing and leading edge pulse width modulation are used. Leading edge modulation can some times lead to simpler control circuitry as will be demonstrated in some circuits. These controllers do not require the multiplier in the voltage feed back loop, error amplifier in the current loop and rectified line voltage sensor, which are needed by traditional control methods. Controller examples and design arc analyzed.

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Electrical Characteristics of Quasi-SOI LDMOSFET (Quasi-SOI LDMOSFET의 전기적 특성)

  • 정두연;이종호
    • Proceedings of the IEEK Conference
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    • 2000.06b
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    • pp.234-237
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    • 2000
  • In this paper, a method to implement new Quasi-SOI LDMOSFET is introduced and the electrical characteristics of the device are studied. Key process steps of the device are explained briefly. By performing process and device simulations, electrical characteristics of the device are investigated, with emphasis on the optimization of the tilt angle of p$\^$0/ channel region. The electrical properties of the Quasi-SOI device are compared with those of bulk and SOI devices with the same process parameters. Simulated device characteristics are threshold voltage, off-state leakage current, subthreshold swing, DIBL, output resistance, lattice temperature, I$\_$D/-V$\_$Ds/, and cut-off frequency.

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A DECOMPOSITION THEOREM FOR UTUMI AND DUAL-UTUMI MODULES

  • Ibrahim, Yasser;Yousif, Mohamed
    • Bulletin of the Korean Mathematical Society
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    • v.58 no.6
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    • pp.1563-1567
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    • 2021
  • We show that if M is a Utumi module, in particular if M is quasi-continuous, then M = Q ⊕ K, where Q is quasi-injective that is both a square-full as well as a dual-square-full module, K is a square-free module, and Q & K are orthogonal. Dually, we also show that if M is a dual-Utumi module whose local summands are summands, in particular if M is quasi-discrete, then M = P ⊕ K where P is quasi-projective that is both a square-full as well as a dual-square-full module, K is a dual-square-free module, and P & K are factor-orthogonal.

A Study on the Quasi-Sliding Mode Condition in Discrete Time Variable Structure Systems (아산시간 가변구조 시스템에서 준 슬라이딩 모드 조건에 관한 연구)

  • 이강웅;최계근
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.8
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    • pp.899-905
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    • 1988
  • In this paper, we suggest a new quasi-sliding mode condition with a wighting factor which guarantees all the states to reach switching planes and improves the convergence of the state trajectories. The result of computer simulation shows that by the suitable selection of a weighting factor, all the state trajectories reach switching planes and enter the sliding mode having the property of the insensitivity to parameter variation and disturbances.

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Determination of Energy Distribution of Interface State Density in the MNOS Memory Device (MNOS 기억소자의 계면상태밀도의 에너지 분포의 결정)

  • 한태현;강창수;박종하;서광열
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1988.10a
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    • pp.1-4
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    • 1988
  • The high frequency and quasi-state C-V curves were measured to determine the interface state density in MNOS devices. Berglund method was appropriate for determination of energy distribution of interface state density all over the energy gap. Applying Vg vs Øs relation by Berlund method to comparison-analysis method of the high-frequency and quasi-static C-V curves, we were able to determine the energy distribution by only measured C-V curves without theoretical C-V curves. The interface state density near the conduction band was high at lower temperature than room temperature.

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Bubble Nucleation and Behavior on Square Micro Heaters (사각 마이크로 히터위에서의 기포의 형성 및 거동)

  • Jung, Jung-Yeul;Kwak, Ho-Young
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1464-1469
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    • 2004
  • In this study, micro square heaters having dimensions of $65{\times}65{\mu}m^2$and $100{\times}100{\mu}m^2$ were fabricated and bubble nucleation experiments on the heaters were performed. Bubble nucleation temperature was also measured using a bridge circuit and the photographs of bubble nucleation and subsequent growth were taken by a camera with a flash unit. Measured bubble nucleation temperatures were found to be closer to the superheat limit of working fluid (FC-72). Also quasi-1D analyses for the square heaters were performed. The quasi-1D analysis yielded proper temperature distribution of the square heater at steady state, however failed to predict the temperature rise up to the steady state. Similar time dependent temperature can be obtained with proper value of thermal diffusivity. For the $100{\times}100{\mu}m^2$ square heater, nucleation of several bubbles was observed while only one bubble was observed to be nucleated on $65{\times}65{\mu}m^2$ heater.

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Method And Mathematical Algorithm For Finding The Quasi-Optimal Purpose Plan

  • Piskunov, Stanislav;Yuriy, Rayisa;Shabelnyk, Tetiana;Kozyr, Anton;Bashynskyi, Kyrylo;Kovalev, Leonid;Piskunov, Mykola
    • International Journal of Computer Science & Network Security
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    • v.21 no.2
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    • pp.88-92
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    • 2021
  • A method and a mathematical algorithm for finding a quasi-optimal assignment plan with rectangular efficiency matrices are proposed. The developed algorithm can significantly reduce the time and computer memory consumption for its implementation in comparison with optimal methods.