• Title/Summary/Keyword: synthesize

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A Study of BaTiO3 Synthesis by Direct Wet Process (BaTiO3의 습식 직접 합성(I))

  • 이경희;이병하;이희승
    • Journal of the Korean Ceramic Society
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    • v.21 no.4
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    • pp.323-326
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    • 1984
  • In this study we are going to develop the process of a synthesis about BaTiO3 at the room temperature. We use BaTiO3 as a high dielectric constant in many dielectric materials and more stable in the temperature, We need high temperature over 1300$^{\circ}C$ for the synthesis of BaTiO3 by the process of industrials and there are difficulty which synthesize a final products not to have a intermediate composition. So we studied to synthesize a pure BaTiO3 from the room temperature to 90$^{\circ}C$ and also to develop the process of synthesis which can control the particle size and which has the final product not to have a intermediate composition.

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Biosynthesis of Two Flavones, Apigenin and Genkwanin, in Escherichia coli

  • Lee, Hyejin;Kim, Bong Gyu;Kim, Mihyang;Ahn, Joong-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.25 no.9
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    • pp.1442-1448
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    • 2015
  • The flavonoid apigenin and its O-methyl derivative, genkwanin, have various biological activities and can be sourced from some vegetables and fruits. Microorganisms are an alternative for the synthesis of flavonoids. Here, to synthesize genkwanin from tyrosine, we first synthesized apigenin from p-coumaric acid using four genes (4CL, CHS, CHI, and FNS) in Escherichia coli. After optimization of different combinations of constructs, the yield of apigenin was increased from 13 mg/l to 30 mg/l. By introducing two additional genes (TAL and POMT7) into an apigenin-producing E. coli strain, we were able to synthesize 7-O-methyl apigenin (genkwanin) from tyrosine. In addition, the tyrosine content in E. coli was modulated by overexpressing aroG and tyrA. The engineered E. coli strain synthesized approximately 41 mg/l genkwanin.

The Studies on the Synthesis of a Tetramethyl-4,4'-diaminobenzophenone (Tetramethyl-4,4'-diaminobenzophenone 合成에 關한 硏究)

  • Jeon, Poong-Jin;Kim, Jin-Il
    • Journal of the Korean Chemical Society
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    • v.4 no.1
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    • pp.67-69
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    • 1957
  • The synthetic method of tetramethyl-4,4'-diaminobenzophenone accomplished by W. Michler is to pass gaseous carbonyl chloride in dimethylaniline until theoretical value of weight increases at room temperature and synthesize the ketone by heating it at above 120$^{\circ}C. In the result of the experiment to synthesize the ketone by Michler's method, it was observed that if gaseous phosgen was to be used at room temperature according to the method, the gas inhaling tube would be closed up by reaction products (gruel-like crystals) before the theoretical amount of gases passed in and causing difficulty for gas to be produce or inhaled With a view to remove the difficulty, the author examined an article published by W. Michler entitled. "The synthesis of organic acid with phosgen" and guessing that the use of liquid phosgen could overcome the difficulty, succeeded in synthesizing the substance in good yield easily by reacting dimethylaniline with phosgen that was condensed into liquid state.

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A Method of Interna State reduction in the Synthesis of Multipul-Input asynchronous Sequential circuits Using Transition-Sensitive Flip-Fops (다입력변화 천이응동비동기순서논리회로의 내부상태 감소법에 관한 연구)

  • 임재탁;이근영
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.11 no.2
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    • pp.22-26
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    • 1974
  • To synthesize transition-sensitive asynchronous sequential circuits, D-type transition-sensitive flip-flop is used.4 new concept, a pair of input state is introduced and used to reduce the number of internal states. We proposed an algorithm to synthesize multiple-input change asynchronous sequential circuits directly from a primitive state table an6 demonstrated the method is better than the one which is due to Bredeson and Hulina and Others.

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physical structure of dynamic systems to implement a given system function (시스템함수를 실현하는 동적시스템의 물리구조에 관하여)

  • 박전수;김종식
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.294-298
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    • 1996
  • This paper presents an attempt to find the physical structure of dynamic systems which achieves the behavior of a given system function. The scheme pursued by te paper would be regarded as synthesizing dynamic systems, and a method to synthesize them analytically is proposed by means of bond graph prototypes. The method proposed adopts several concepts used to synthesize networks in the electrical field, but yet demonstrates its own strengths such as the freedom from the causality assignment and determination of junction types. Also, it is shown that this method has further advantages in reticulating a given specification into feedforward and feedback expansions relative to electrical network synthesis and the method introduced by Redfield. The proposed method is examined through an example to trace the outline of the analytical synthesis of dynamic systems using bond graph prototypes.

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Isolation and Identification of Tetrodotoxin-producing Marine Microorganism from Pufferfish (복어로부터 복어독(Tetrodotoxin) 생성능이 있는 해양 미생물의 분리 및 동정)

  • 윤성준;차병윤;이명자;정동윤;송병권;김희숙;김동수;이은열
    • Journal of Life Science
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    • v.9 no.6
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    • pp.653-658
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    • 1999
  • A novel marine microorganism, Vibrio sp. YE-101, was isolated from pufferfish and investigated for its ability to synthesize tetrodotoxin (TTX). Various strains isolated from the intestine of pufferfish were grown on TCBS agar plate, and then cultured on Ocean Research Institute (ORI) medium supplemented with 3% NaCl at 23$^{\circ}C$ for 3days. The cells were harvested, disrupted, fractionated by Bio-Gel P-2 column chromatography and then TTX-producing strain, Vibrio sp. YE-101, was identified using mouse bioassay. The isolated TTX from Vibrio sp. YE-101 was also analyzed and identified by HPLC and gas chromatography-mass spectrometer (GC-MS). The mass fragmentation of trimethylsilyl derivatives of C9-base of TTX from Vibrio sp. YE-101 was interpreted and the pattern of fragmentation was same with that of authentic standard. The purfied TTX was also positive to the mouse bioassay, which clearly represents that Vibrio sp. YE-101 can synthesize TTX.

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Realization of Digital Music Synthesizer Using a Frequency Modulation (FM 방식을 이용한 디지탈 악기음 합성기의 구현)

  • 주세철;김진범;김기두
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.7
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    • pp.1025-1035
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    • 1995
  • In this paper, we realize a real time digital FM synthesizer based on genetic algorithm using a general purpose digital signal processor. Especially, we synthesize diverse music sounds nicely using a synthesis model consisting of a single modulator and multiple carriers. Also we present genetic algorithm-based technique which determines optimal parameters for reconstruction through FM synthesis of a sound after analyzing the spectrum of PCM data as a standard music sound using FFT. Using the suggested parameter extractiuon algorithm, we extract parameters of several instruments and then synthesize digital FM sounds. To verify the validity of the parameter extraction algorithm as well as realization of a real time digital music synthesizer, the evaluation is first done by listening the sound directly as subjective test. Secondly, to evaluate the synthesized sound objectively with an engineering sense, we compare the synthesized sound with an original one in a time domain and a frequency domain.

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Advanced Algorithm for $H_{\infty}$ Optimal controller synthesis ($H_{\infty}$ 최적 제어기 구성을 위한 개선된 알고리즘)

  • 김용규;양도철;유창근;장호성
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.149-152
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    • 2002
  • The aim of this study is to analyse the problems occurred by using classical algorithm to synthesize the H$\infty$ optimal controller. The obtained result of analysis applied to the composition of algorithm for the new H$\infty$ optimal controller which was introduced in this study. The study investigates and compares H$\infty$ optimal controller formed by new algorithm with the one formed by classical algorithm. In particular, robustness related to the robust control is systematically described by using the composition of algorithm for the classical H$\infty$ optimal controller. In addition, the flow charts classified into classical algorithm and new one are discussed to synthesize the H$\infty$ optimal controller.

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PROSODY CONTROL BASED ON SYNTACTIC INFORMATION IN KOREAN TEXT-TO-SPEECH CONVERSION SYSTEM

  • Kim, Yeon-Jun;Oh, Yung-Hwan
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1994.06a
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    • pp.937-942
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    • 1994
  • Text-to-Speech(TTS) conversion system can convert any words or sentences into speech. To synthesize the speech like human beings do, careful prosody control including intonation, duration, accent, and pause is required. It helps listeners to understand the speech clearly and makes the speech sound more natural. In this paper, a prosody control scheme which makes use of the information of the function word is proposed. Among many factors of prosody, intonation, duration, and pause are closely related to syntactic structure, and their relations have been formalized and embodied in TTS. To evaluate the synthesized speech with the proposed prosody control, one of the subjective evaluation methods-MOS(Mean Opinion Score) method has been used. Synthesized speech has been tested on 10 listeners and each listener scored the speech between 1 and 5. Through the evaluation experiments, it is observed that the proposed prosody control helps TTS system synthesize the more natural speech.

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Comparision of Irregular Quadtree Decomposition with Full-search Block Matching for Synthesizing Intermediate Images

  • Kim, Kyung-Tae
    • Journal of the Optical Society of Korea
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    • v.8 no.3
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    • pp.108-114
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    • 2004
  • To allow multiple viewers to see the correct perspective and to provide a singh1 viewer with motion parallax cues during head movement, more than two views arc needed. Since it is prohibitive to acquire, process, and transmit a continuum of views, it. would preferable to acquire only a minimal set of views and to synthesize intermediate images. This paper presents how to synthesize the intermediate images using irregular quadtree decomposition and compares the proposed methods with full-search block matching. The image at the middle viewpoint between both viewpoints is synthesized and yields a 32.8 ㏈ peak-signal-to-noise ratio (PSNR) which is 2.8 ㏈ high and has a running time 30% of that for conventional full-search block matching.