• Title/Summary/Keyword: Delta-1

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Synthesis of 2-acetyl 11-keto-.DELTA.12;13 oleanolic ketol acetate and other derivatives (2-acrtyl-11-keto-.DELTA.12;13-oleanolic ketol acetate급 기타 유도체의 합성)

  • 김경호
    • YAKHAK HOEJI
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    • v.6 no.1
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    • pp.25-27
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    • 1962
  • The derivative of glycyrrhetinic acid which have similar effects of desoxycorticosterone acetate was prepared glycyrrhetinyl chloride by the chlorination with thionyl chloride at low temperature. 2-Acetyl-11-keto-.DELTA. : 13 oleanolic ketol acetate (30) was synthesized by diazotating glycyrrhetinyl chloride with diazomethan and the acetylation with anhydro acetic acid. 2-Acetyl-.DELTA.12 : 13 oleanolic ketol acetate (28) was synthesized by chlorinating oleanolic acid with thionyl chloride, and by diazotatating oleanolyl chloride with diazomethan and the acetylation with anhydroacetic acid.

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광주천 인근 지하수의 수질 및 안정동위원소 특성

  • Yoon, Wook;Ji, Se-Jung
    • Proceedings of the KSEEG Conference
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    • 2003.04a
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    • pp.116-120
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    • 2003
  • 광주 지하수의 대수층은 주로 원형의 화강암 저지대 분지에 형성되어 있으며, 동남부 무등산(1,187m) 일대가 지하수의 주요 함양원 이다. 총 7,540 여 개의 지하수 관정으로부터 하루에 양수되는 추정 배출량은 59,455㎥ 이상으로 보고되고 있다(건설교통부,2000년). 도심지에서는 지하수가 생활 및 공업용수로 주로 이용되나, 농촌지역에서는 음용수 및 농업용수로 사용되고 있다. (중략)

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An Algorithm to Reduce the Pitch Computational amount using Modified Delta Searching in CELP Vocoders (CELP 보코더에서 델타 피치 검색 방법 개선에 대한 연구)

  • Ju, Sang-Gyu
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.269-272
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    • 2010
  • In this paper, we propose the computation reduction methods of delta pitch search that is used in G.723.1 vocoder. In order to decrease the computational amount in delta pitch search the characteristic of proposed algorithms is as the following. First, scheme to reduce the computation amount in delta pitch search uses NAMDF. Developed the second scheme is the skipping technique of lags in pitch searching by using the threshold value. By doing so, we can reduce the computational amount of pitch searching more than 64% with negligible quality degradation.

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C-Glucuronide from O-Glucuronyl Trichloroacetimidate

  • Baek, Seung-Hwa
    • Bulletin of the Korean Chemical Society
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    • v.12 no.6
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    • pp.604-606
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    • 1991
  • From O-glucuronyl trichloroacetimidate (4) and ${\Delta}^6$-tetrahydrocannabinol (5), the C-glucuronide of ${\Delta}^6-tetrahydrocannabinol({\Delta}^6-THC)$ (7) was obtained using mild Lewis acid catalysis. The known method for the synthesis of C-glucuronide from 1-O-unprotected glucuronide provided low chemical yields. The C-glucuronide of ${\Delta}^6-THC$ was obtained through inversion of configuration at the anomeric center in O-glucuronyl trichloroacetimidate (4).

APPROXIMATION BY CONVOLUTION TYPE DELTA SEQUENCE IN HIGHER DIMENSION

  • Shim, Hong-Tae;Park, Chin-Hong
    • Journal of applied mathematics & informatics
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    • v.16 no.1_2
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    • pp.633-641
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    • 2004
  • In this paper we deal with functions in higher dimension. We provide several convergence theorem for approximation by convolution type delta sequence. We also give sufficient and necessary condition for Gibbs phenomenon to exist.

UNIVALENT HARMONIC EXTERIOR MAPPINGS

  • Jun, Sook Heui
    • Journal of the Chungcheong Mathematical Society
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    • v.16 no.2
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    • pp.31-41
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    • 2003
  • In this paper, we will show that the bounds for coefficients of harmonic, orientation-preserving, univalent mappings f defined on ${\Delta}$ = {z : |z| > 1} with $f({\Delta})={\Delta}$ are sharp by finding extremal functions.

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On Almost Continuity

  • Ekici, Erdal
    • Kyungpook Mathematical Journal
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    • v.46 no.1
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    • pp.119-130
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    • 2006
  • A new class of functions is introduced in this paper. This class is called almost ${\delta}$-precontinuity. This type of functions is seen to be strictly weaker than almost precontinuity. By using ${\delta}$-preopen sets, many characterizations and properties of the said type of functions are investigated.

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Performance Improvement of Backpropagation Algorithm by Automatic Tuning of Learning Rate using Fuzzy Logic System

  • Jung, Kyung-Kwon;Lim, Joong-Kyu;Chung, Sung-Boo;Eom, Ki-Hwan
    • Journal of information and communication convergence engineering
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    • v.1 no.3
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    • pp.157-162
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    • 2003
  • We propose a learning method for improving the performance of the backpropagation algorithm. The proposed method is using a fuzzy logic system for automatic tuning of the learning rate of each weight. Instead of choosing a fixed learning rate, the fuzzy logic system is used to dynamically adjust the learning rate. The inputs of fuzzy logic system are delta and delta bar, and the output of fuzzy logic system is the learning rate. In order to verify the effectiveness of the proposed method, we performed simulations on the XOR problem, character classification, and function approximation. The results show that the proposed method considerably improves the performance compared to the general backpropagation, the backpropagation with momentum, and the Jacobs'delta-bar-delta algorithm.

Autopilot Design Using LQG/LTR Method for a Launch Vehicle (LQG/LTR 기법에 의한 발사체의 자동조종장치 설계)

  • Kim, Seung-Hwan;Kwon, Oh-Kyu
    • Proceedings of the KIEE Conference
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    • 1990.11a
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    • pp.413-416
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    • 1990
  • This paper proposes a design procedure based on the LQG/LTR method for a launch vehicle autopilot. Continuous-discrete type LQG/LTR compensators are designed using the $\delta$-transformation [1] in order to overcome numerical problems occurring in the process of discretization. The $\delta$-LQG/LTR compensator using the $\delta$-transformation is compared with the $\delta$-LQG/LTR compensator using the $\delta$-transformation. The performance of the overall system controlled by the $\delta$-LQG/LTR compensator is evaluated via simulations, which show that the discretization error problem is resolved and the control performances are satisfied in the proposed compensator.

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LIE TRIPLE DERIVATIONS ON FACTOR VON NEUMANN ALGEBRAS

  • Liu, Lei
    • Bulletin of the Korean Mathematical Society
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    • v.52 no.2
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    • pp.581-591
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    • 2015
  • Let $\mathcal{A}$ be a factor von Neumann algebra with dimension greater than 1. We prove that if a linear map ${\delta}:\mathcal{A}{\rightarrow}\mathcal{A}$ satisfies $${\delta}([[a,b],c])=[[{\delta}(a),b],c]+[[a,{\delta}(b),c]+[[a,b],{\delta}(c)]$$ for any $a,b,c{\in}\mathcal{A}$ with ab = 0 (resp. ab = P, where P is a fixed nontrivial projection of $\mathcal{A}$), then there exist an operator $T{\in}\mathcal{A}$ and a linear map $f:\mathcal{A}{\rightarrow}\mathbb{C}I$ vanishing at every second commutator [[a, b], c] with ab = 0 (resp. ab = P) such that ${\delta}(a)=aT-Ta+f(a)$ for any $a{\in}\mathcal{A}$.