• Title/Summary/Keyword: Synthesis

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Total Synthesis of Isopimarol Diterpene (Isopimarol Diterpene의 전합성)

  • 서영거;전라옥
    • YAKHAK HOEJI
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    • v.43 no.6
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    • pp.696-702
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    • 1999
  • The first and versatile total synthesis of isopimarol diterpene has been achieved via stereoselective construction of C-13 quaternary carbon unit as a key step. Isopimarol diterpene was synthesized from the known decalone in 17% overall yield of 16 steps.

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Synthesis, properties and applications of Halogen containing polyimides

  • Kravtsova, V.D.;Zhubanov, B.A.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.255-258
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    • 2000
  • The new approach for synthesis of novel condensation monomers and polyimides on the basis of them was developed. The correlation between synthesis regularities, structure and properties of monomers and polyimides was studied. The areas of industrial application of synthesized polymer were determined.

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Template Synthesis of New Polyazamacrocycles

  • Lee, Young-Hoon;Lee, Man-Kil
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.339.2-339.2
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    • 2002
  • Interest in the synthesis and chemistry of multidentate macrocyclic ligands is currently very high. Synthetic macrocycles arise from the fact that many biologically important molecules are metal complexes of macrocyclic organic systems: and in order to understand the mechanism of action of the naturally occurring complexes. chemists have resorted to the synthesis and study of so-called model systems. (omitted)

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Design of Linguistic Contents of Speech Copora for Speech Recognition and Synthesis for Common Use (공동 이용을 위한 음성 인식 및 합성용 음성코퍼스의 발성 목록 설계)

  • Kim Yoen-Whoa;Kim Hyoung-Ju;Kim Bong-Wan;Lee Yong-Ju
    • MALSORI
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    • no.43
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    • pp.89-99
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    • 2002
  • Recently, researches into ways of improving large vocabulary continuous speech recognition and speech synthesis are being carried out intensively as the field of speech information technology is progressing rapidly. In the field of speech recognition, developments of stochastic methods such as HMM require large amount of speech data for training, and also in the field of speech synthesis, recent practices show that synthesis of better quality can be produced by selecting and connecting only the variable size of speech data from the large amount of speech data. In this paper we design and discuss linguistic contents for speech copora for speech recognition and synthesis to be shared in common.

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Facile Regiocontrolled Three-Step Synthesis of Poly-Substituted Furans, Pyrroles, and Thiophenes: Consecutive Michael Addition of Methyl Cyanoacetate to α,β-Enone, CuI-Mediated Aerobic Oxidation, and Acid-Catalyzed Paal-Knorr Synthesis

  • Kim, Se-Hee;Lim, Jin-Woo;Lim, Cheol-Hee;Kim, Jae-Nyoung
    • Bulletin of the Korean Chemical Society
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    • v.33 no.2
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    • pp.620-624
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    • 2012
  • An efficient synthesis of poly-substituted furans, pyrroles, and thiophenes was carried out in a regiocontrolled manner via a three-step process; (i) conjugate addition of methyl cyanoacetate derivatives to ${\alpha}$,${\beta}$-enones, (ii) CuI-mediated aerobic oxidation, and (iii) Paal-Knorr type synthesis of five-membered heterocycles.

Model based optimal FIR synthesis filter for a nosy filter bank system

  • Lee, Hyun-Beom;Han, Soo-Hee;Kwon, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.413-418
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    • 2003
  • In this paper, a new multirate optimal finite impulse response (FIR) filter is proposed for the signal reconstruction in the nosy filter bank systems. The multirate optimal FIR filter replaces the conventional synthesis filters and the Kalman synthesis filter. First, the generic linear model is derived from the multirate state space model for an autoregressive (AR)input signal. Second, the multirate optimal FIR filter is derived from the multirate generic linear model using the minimum variance criterion. This paper also provides numerical examples and results. The simulation results illustrate that the performance is improved compared with conventional synthesis filters and the proposed filter has advantages over the Kalman synthesis filter.

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Colloidal Synthesis of Octahedral Shaped PbSe Nanocrystals from Lead Oleate and Se : Temperature Effect

  • Gokarna, Anisha;Jun, Ki-Won;Khanna, P.K.;Baeg, Jin-Ook;Seok, Sang-Il
    • Bulletin of the Korean Chemical Society
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    • v.26 no.11
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    • pp.1803-1806
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    • 2005
  • Formation of octahedral shaped PbSe quantum dots at higher synthesis temperature is being reported in this paper. The synthesis includes the reaction between lead oleate and trioctylphosphine selenide under inert gas conditions to produce PbSe. TEM, SEM, XRD and EDS were used to characterize the samples. The SEM exhibited the formation of spherical shaped nanocrystals at temperature below 140 ${^{\circ}C}$ and octahedral shaped nanoparticles at higher temperatures. Moreover, the TEM also showed the well resolved (111) lattice fringes proving that the nanocrystals were crystalline in nature. Synthesis of highly pure PbSe nanocrystals was another interesting aspect of this research.

Biological green synthesis of gold and silver nanoparticles

  • Sur, Ujjal Kumar
    • Advances in nano research
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    • v.2 no.3
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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.

Perceptual Evaluation of Duration Models in Spoken Korean

  • Chung, Hyun-Song
    • Speech Sciences
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    • v.9 no.1
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    • pp.207-215
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    • 2002
  • Perceptual evaluation of duration models of spoken Korean was carried out based on the Classification and Regression Tree (CART) model for text-to-speech conversion. A reference set of durations was produced by a commercial text-to-speech synthesis system for comparison. The duration model which was built in the previous research (Chung & Huckvale, 2001) was applied to a Korean language speech synthesis diphone database, 'Hanmal (HN 1.0)'. The synthetic speech produced by the CART duration model was preferred in the subjective preference test by a small margin and the synthetic speech from the commercial system was superior in the clarity test. In the course of preparing the experiment, a labeled database of spoken Korean with 670 sentences was constructed. As a result of the experiment, a trained duration model for speech synthesis was obtained. The 'Hanmal' diphone database for Korean speech synthesis was also developed as a by-product of the perceptual evaluation.

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