• 제목/요약/키워드: Large-scale synthesis

검색결과 152건 처리시간 0.025초

시간지연을 갖는 이산시간 대규모 시스템의 강인 안정화 (Robust Stabilization of Large-Scale Discrete-Time Systems with Time-Delays)

  • 박주현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2293-2295
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    • 2000
  • This paper describes the synthesis of robust decentralized controllers for uncertain large-scale discrete-time systems with time-delays in subsystem interconnections. Based on the Lyapunov method, a sufficient condition for robust stability, is derived in terms of a linear matrix inequality(LMI). The solutions of the LMI can be easily obtained using various efficient convex optimization techniques. A numerical example is given to illustrate the proposed method.

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Protection Process of the tert-Butyl Group as a Non-Polar Moiety of D-Serine: Unexpected Rearrangement

  • Choi, Bo-Eun;Jeong, Jin-Hyun
    • Archives of Pharmacal Research
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    • 제23권6호
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    • pp.564-567
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    • 2000
  • The use of amino acid derivatives as building blocks in peptide synthesis is increasingly being recognized as a potential route for the development of pharmaceutical agents. Side chain protection of polyfunctional amino acids such as Ser, Thr, Tyr is viewed as being particularly important. Although these derivatives are commercially listed, they are expensive and not widely available. We describe here a practical large-scale synthesis of t-butyl introduced D-serine, one of the building blocks of zoladex, a peptide drug.

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진세노사이드 $Rh_2$의 방향선택적 합성 (Regioselective Synthesis of Ginsenoside $Rh_2$)

  • 신명희;정지형;장은하;임광식
    • 약학회지
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    • 제45권4호
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    • pp.328-333
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    • 2001
  • Ginsenoside Rh$_2$, a minor glycoside constituent of the red ginseng is known as an unique antitumor compound. Several attempts to prepare it in a large scale including semisynthesis from betulafolientriol, an 3-epimer of 20(S)-protopanaxadiol, has been reported. We have previously reported a synthesis of ginsenoside Rh$_2$from 20(S)-protopanaxadiol obtained by alkaline hydrolysis of total ginsenoside. The regioselective synthesis of this compound was achieved by protection of 12-OH group.

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A New Pruning Method for Synthesis Database Reduction Using Weighted Vector Quantization

  • Kim, Sanghun;Lee, Youngjik;Keikichi Hirose
    • The Journal of the Acoustical Society of Korea
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    • 제20권4E호
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    • pp.31-38
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    • 2001
  • A large-scale synthesis database for a unit selection based synthesis method usually retains redundant synthesis unit instances, which are useless to the synthetic speech quality. In this paper, to eliminate those instances from the synthesis database, we proposed a new pruning method called weighted vector quantization (WVQ). The WVQ reflects relative importance of each synthesis unit instance when clustering the similar instances using vector quantization (VQ) technique. The proposed method was compared with two conventional pruning methods through the objective and subjective evaluations of the synthetic speech quality: one to simply limit maximum number of instance, and the other based on normal VQ-based clustering. The proposed method showed the best performance under 50% reduction rates. Over 50% of reduction rates, the synthetic speech quality is not seriously but perceptibly degraded. Using the proposed method, the synthesis database can be efficiently reduced without serious degradation of the synthetic speech quality.

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대용량 인버터 시스템을 위한 공간벡터 PWM 인버터의 병렬 운전 (Parallel Operation of Space Vector PWM Inverters for Large Capacity Inverter System)

  • 지준근;이현동
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제49권8호
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    • pp.509-513
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    • 2000
  • This paper deals with the parallel operation of space vector PWM for large capacity inverter system. To enlarge the capacity of inverter system and to reduce the current ripples on inverter output side, two or more inverters are operated in parallel. In this paper, a new parallel operation strategy which minimizes the harmonic distortion of the output stage is described. The proposed method is developed on the basis of the space-vector PWM in order to increase the linearly controllable voltage range. With the help of the proposed voltage synthesis method, the total harmonic distortion of the output stage can be greatly reduced in compared with that of conventional method with sinusoidal PWM or that of the single inverter operation case. The experimental results with reduced scale test show the feasibility of the proposed voltage synthesis method.

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Biological green synthesis of gold and silver nanoparticles

  • Sur, Ujjal Kumar
    • Advances in nano research
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    • 제2권3호
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    • pp.135-145
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    • 2014
  • Nanomaterials synthesized by natural bioresources such as microorganisms, animals and plants in nature can also be synthesized in laboratories even on large scale. This is considered as an attractive prospect for eco-friendly or so-called green synthesis. Development of eco-friendly synthesis of biocompatible nanoparticles and their potential biomedical applications introduces the concept of nanobiotechnology. The lower cost and lesser side effects as compare to chemical methods of synthesis are the main advantages of biosynthesis. This review article demonstrates the role of various biological resources e.g. bacteria, fungi, actinomycetes, plant leaves, fruits and honey as well as animal tissues for the synthesis of nanoparticles mainly gold and silver with an overview of their potential applications.

Fabrication of Large-Scale Single-Crystal Organic Nanowire Arrays for High-Integrated Flexible Electronics

  • 박경선;성명모
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.266.1-266.1
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    • 2013
  • Large-scale single-crystal organic nanowire arrays were generated using a direct printing method (liquidbridge- mediated nanotransfer molding) that enables the simultaneous synthesis, alignment and patterning of nanowires from molecular ink solutions. Using this method, single-crystal organic nanowires can easily be synthesized by self-assembly and crystallization of organic molecules within the nanoscale channels of molds, and these nanowires can then be directly transferred to specific positions on substrates to generate nanowire arrays by a direct printing process. Repeated application of the direct printing process can be used to produce organic nanowire-integrated electronics with two- or three-dimensional complex structures on large-area flexible substrates. This efficient manufacturing method is used to fabricate all-organic nanowire field-effect transistors that are integrated into device arrays and inverters on flexible plastic substrates.

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NNDI decentralized evolved intelligent stabilization of large-scale systems

  • Chen, Z.Y.;Wang, Ruei-Yuan;Jiang, Rong;Chen, Timothy
    • Smart Structures and Systems
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    • 제30권1호
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    • pp.1-15
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    • 2022
  • This article focuses on stability analysis and fuzzy controller synthesis for large neural network (NN) systems consisting of several interconnected subsystems represented by the NN model. Advanced and fuzzy NN differential inclusion (NNDI) for stability based on the developed algorithm with H infinity can be designed based on the evolved biological design. This representation is constructed using sector linearity for NN models. Sector linearity transforms a non-linear model into a linear model based on proposed operations. New sufficient conditions are realized in the form of LMI (linear matrix inequalities) to ensure the asymptotic stability of the trans-Lyapunov function. This transforms the nonlinear model into a linear model based on multiple rules. At last, a numerical case study with simulations is derived as illustration to prove its feasibility in real nonlinear structures.