• Title/Summary/Keyword: separations

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Local Recovery in Reliable Multicasting Protocols Applying Separations of Concerns to the NAK message (신뢰성 있는 멀티캐스팅 프로토콜에서 NAK 메시지의 기능분리를 통한 지역적 오류 복구)

  • 이윤희;정충일;박창윤
    • Proceedings of the Korean Information Science Society Conference
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    • 2000.10c
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    • pp.570-572
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    • 2000
  • 멀티캐스팅 프로토콜에서 중요하게 요구되는 사항은 신뢰성과 확장성이다. 그 중 확장성을 향상시키기 위해서 여러 지역적 오류 복구 기법이 사용되고 있다. 본 논문에서는 기존의 지역적 오류 복구 기법에서 발생하는 제한점을 설명하고, 이 문제를 해결하기 위해서 지역대표에 의한 NAK 메시지의 기능분리 방법을 제안하고 구현하였다. 그리고, 제안된 방법에 대해서 시뮬레이션을 통해 확장성에 대한 성능평가를 하였다.

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Strategic Cattle Roundup using Multiple Quadrotor UAVs

  • Jung, Sunghun;Ariyur, Kartik B.
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.2
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    • pp.315-326
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    • 2017
  • Four quadrotor UAVs are maneuvered to guide four animals into their pen within the minimum time by creating noises of predators modeled with an exponential function. The quadrotor UAVs are controlled via PID controllers, follow time optimal trajectories, and avoid collisions through altitude separations. The stability of the proposed PID controller is analyzed and verified using MATLAB/Simulink based simulations. Proposed step by step strategies would be practical solutions of actual cattle roundup problems.

Applications of Polymers in Bioseparations and Delivery of Biomolecules

  • Hoffman, Allan S.
    • Journal of Biomedical Engineering Research
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    • v.7 no.2
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    • pp.109-110
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    • 1986
  • Polymers are widely applied in bioseparation processes as well as in drug delivery systems. These two fields have a certain commonality, in that they involve either removal or delivery of specific biomolecules from or to an aqueous environment It is also to be noted that therapeutic toxin renloval is an example of a bioseparation process. This presentation will focus on the use of polys!ors in physical as well as biospecific separations and delivery of biomolecules. Several new systems will also be described.

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HPLC Resolution of Enantiomers Using Polysaccharide Derivatives as Chiral Stationay Phases

  • Okamoto, Yoshio
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.163-164
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    • 2002
  • In the past two decades, separations of enantiomers (optical isomers) by high-performance liquid chromatography (HPLC) have remarkably advanced [1]. Among many commercially available chiral stationary phases (CSPs) for HPLC, polysaccharide-based CSPs are the most popular ones, which can cover the resolution of a wide range of the chiral compounds [2, 3, 4]. Here, I will explain mainly the HPLC separation of enantiomers using these CSPs. (omitted)

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Theoretical Overview of Membrane Transport (막물질 이동의 이론적 고찰)

  • Park, Young
    • Membrane Journal
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    • v.3 no.3
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    • pp.94-107
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    • 1993
  • Many researchers have discussed how membrane performance can be enhanced through an understanding of polymer science and engineering. The understandings of transport in porous membrane are used to achieve the isolation of certain components from mixtures. Particular emphasis is placed on the applicability of membrane separations for the isolation of macromolecules[1]. An awareness of membrane structure characteristics is required for the rational design of membranes for specific and/or new applications. This understanding rests on the knowledge of fields such as polymer thermodynamics[2], polymer adsorption [3, 4], diffusion in polymers[5, 6], reaction mechanism[7], and the dynamic behavior[8, 9] of polymer in porous membrane.

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A Symbolic Layout Generator for CMOS Standard Cells Using Artificial Intelligence Approach (인공지능 기법을 이용한 CMOS 표준셀의 심볼릭 레이아웃 발생기)

  • 유종근;이문기
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.6
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    • pp.1080-1086
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    • 1987
  • SLAGEN, a system for symbolic cell layout based on artificial intelligence approach, takes as input a transistor connection description of CMOS standard cells and environment information, and outputs a symbolic layout description. SLAGEN performas transistor grouping by a heuristic search method, in order to minimize the number of separations, and then performs group reordering and transistor reordering with an eye toward minimizing routing. Next, SLAGEN creates a rough initial routing in order to guarantee functionality and correctness, and then improve the initial routing by a rule-based approach.

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Gas Separation Membranes - Current Status

  • Puri, Pushpinder S.
    • Membrane Journal
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    • v.6 no.3
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    • pp.117-126
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    • 1996
  • Membrane-based gas separation systems are now widely accepted and employed as unit operation in industrial gas, chemical, and allied industries. Following their successful commercialization in the late seventies to recover hydrogen from ammonia purge gas streams, membrane-based systems have gained acceptance in a wide variety of applications. Numerous systems are in operation today to: recover hydrogen from other purge gas and hydrocarbon streams; adjust the $H_{2}/CO$ ratio in syngas; remove $CO_{2}$ from natural gas; recover helium; dry gas streams; and separate air. Lower cost, ease of operation, operational flexibility and portability are a few of the reasons membrane-based systems are chosen over absorption and cryogenic-based separations in certain applications.

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A Study on the Application of Ultrafiltration Membranes for Separations and Purifications of Proteins (단백질의 분리정제를 위한 한외여과막의 응용에 대한 연구)

  • 손동호;전회진;조남준;구자경
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05b
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    • pp.98-101
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    • 2004
  • 최근에 이루어지고 있는 생명공학의 성장에 따라 단백질을 대량으로 정제할 수 있는 공정 개발에 대한 필요성이 부각되고 있다. 이러한 목적으로 기존에 이루어지고 있는 침전법, 결정화법 그리고 원심분리법과 같은 방법은 선택도가 매우 떨어지는 단점이 있으며, 반면 크로마토그래피 및 전기영동과 같은 방법은 탁월한 선택도에 비해 그 규모가 매우 작은 경우 에 알맞은 방법으로서 대량생산 체계에서는 적합하지 못하다는 것이 그 단점이다.(중략)

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Novel Polypyrrole composite membrane with high gas selectivity and permeability

  • Son, Won-Il;Kim, Byoung-Sik;Hong, Jae-Min
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05b
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    • pp.147-152
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    • 2004
  • Gas separation membrane technology is useful for a variety of applications [1, 2]. such as hydrogen recovery from reactor purge gas, nitrogen and oxygen enrichment, water vapor removal from air, stripping of carbon dioxide from natural gas. etc. Although membrane separations are attractive because of low energy costs and simple operation, low permeabilities and/or selectivity often limit membrane applications [3, 4].(omitted)

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Separations of polystyrene sulfonate by dual pump field flow fractionation using UF hollow fiber membranes (듀얼펌프 중공사막 흐름 장 흐름 분회법을 사용하여 다당류(Polystyrene sulfonate)의 분리)

  • 정도연;최승렬;이승윤;민병렬
    • Proceedings of the Membrane Society of Korea Conference
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    • 2004.05b
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    • pp.192-194
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    • 2004
  • FFF에서 외부장은 시료의 종류에 따라 선택적으로 사용되며, 그 외부장의 종류에 따라 세부기술로 구분되어진다. 원심력(gravitational or centrifugal field)을 외부장으로 사용하는 침강장-흐름분획법(sedimentation FFF)은 지름이 0,05∼1um정도인 콜로이드 입자의 분리에 좋은 방법이다. 온도구배(thermal fradient)를 이용하는 열장-흐름분획법(thermal FFF)은 유기 고분자의 분리 및 고분자의 물성연구에 이용된다.(중략)

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