• 제목/요약/키워드: Total Synthesis

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A Study on the Identification and Improvement of Dynamic Characteristics of Large Structure by Component Mode Synthesis Method (부분 구조합성법을 이용한 대형구조물의 동특성 규명 및 개선에 관한 연구)

  • 오재응;이정환;임동규
    • Journal of KSNVE
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    • v.4 no.3
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    • pp.327-335
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    • 1994
  • In this paper, to identify the dynamic characteristics of antenna system, the antenna is divided into 4 components and those were analyzed with a conventional FEM package MSC/NASTRAN. Using a Component Mode Synthesis Method, dynamic characteristics of total system is also identified. The Coherence of each component to total system is evaluated by using strain and kinetic component to total system is evaluated by using strain and kinetic energy. The improving strategy of dynamic characteristics is suggested by changing mass and stiffness of large coherence components.

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Influence of Refeeding with Vitamin, Mineral and Fibre on Protein Synthesis and Messenger Ribonucleic Acid Content in the Liver and Muscle of Fasted Chicks

  • Aman Yaman, M.;Kita, K.;Pinontoan, R.;Okumura, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.5
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    • pp.545-549
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    • 1998
  • The influence of refeeding with either vitamin, mineral, fibre of water on protein synthesis and mRNA content in the liver and breast muscle of fasted chicks was investigated. At 15 d of age, chicks were fasted for 2 d and then refed either vitamin, mineral, fibre or water. The fractional synthesis rate (FSR) of protein was measured after 30 min of refeeding by using a large dose injection of L - 2, $6[^3H]$ phenylalanine. In the liver, FSR was reduced by fasting and tended to increase but not significantly by refeeding with vitamin or mineral. FSR was not affected by refeeding with fibre or water. There was no influence of fasting and refeeding on ribosomal capacity (the RNA : protein ratio) and ribosomal efficiency (total protein synthesised per total RNA). The absolute synthesis rate (ASR) of liver protein and hepatic mRNA content were reduced by fasting and unchanged by refeeding. In the muscle, FSR, ASR and mRNA content were significantly decreased by fasting and not recovered by refeeding with either vitamin, mineral, fibre or water. It concluded that vitamin, mineral, fibre and water have little capacity to stimulate liver and muscle protein synthesis reduced by fasting.

First Total Synthesis of Highly Anti-Inflammatory Active Licochalcone D Through Water-Accelerated [3,3]-Sigmatropic Rearrangement

  • Kim, Si-Jun;Jun, Jong-Gab
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.54-58
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    • 2013
  • Licochalcones, derived from the dried roots of Glycyrrhiza inflata, have been reported to show various biological activities including antitumor, antiparasitic, antileishmanial, antioxidative, superoxide scavenging, antibacterial, and PTP1B activity. Licochalcone D has an allyl group on ring A instead of ring B, however, most other natural licochalcones possess the group on ring B. Total synthesis of licochalcone D has not been reported even possessing the strongest anti-inflammatory activity. Therefore, the first total synthesis of licochalcone D has been developed by using water-accelerated [3,3]-sigmatropic rearrangement method.

A Frequency Transfer Function Synthesis of QFT Using Total Least Squares Method (완전최소자승법을 이용한 QFT의 주파수 전달함수 합성법)

  • Kim, Ju-Sik;Lee, Sang-Hyuk
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.8
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    • pp.649-654
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    • 2002
  • The essential philosophy of the QFT(Quantitative Feedback Theory) is that a suitable controller can be found by loop shaping a nominal loop transfer function such that the frequency response of this function does not violate the QFT bounds. The loop shaping synthesis involves the identification of a structure and its specialization by means of the parameter optimization. This paper presents an optimization algorithm to estimate the controller parameters from the frequency transfer function synthesis using the TLS(Total Least Squares) in the QFT loop shaping procedure. The proposed method identifies the parameter vector of the robust controller from an overdetermined linear system developed from rearranging the two dimensional system matrices and output vectors obtained from the QFT bounds. The feasibility of the suggested algorithm is illustrated with an example.

First Total Synthesis of (-)-Antofine by Using Catalytic Phase Transfer Alkylation.

  • Lee, Jae-Kwang;Lee, Tae-Ho;Park, Hyeung-Geun;Kim, Deuk-Joon;Kim, Sang-Hee
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.183.3-183.3
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    • 2003
  • Phenanthroindolizidine alkaloid, (-)-antofine has attracted attention because of its extremely potent inhibition of cancer cell growth (Its $IC_50$ values have the low nanomolar range). The frist asymmetric total synthesis of (-)-antofine is described. An important feature of this synthesis is the creation of a stereogenic center by enantioselective alkylation using the phase transfer catalyst (PTC) and ring-closing metathesis (RCM) for pyrrolidine ring construction. This synthesis is efficient to allow the asymmetric preparation of other naturally occurring phenanthroindolizidine and phenanthroquinolizidine alkaloid.

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