• Title/Summary/Keyword: $\alpha$-step

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Improvement of Transient Step Response Using Feedforward Compensator in Nonminimum Phase Systems

  • Kwon, Byung-Moon;Ryu, Hee-Seob;Kwon, Oh-Kyu
    • Transactions on Control, Automation and Systems Engineering
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    • v.3 no.3
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    • pp.152-158
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    • 2001
  • This paper proposes a simple feedforward compensator in order to decrease the amount of undershoots and overshoots on the step response in nonminimum phase systems. The compensator makes the step type input be a ramp input with saturation for 0$\leq$t<${\alpha}$. It is shown in this paper that the compensated system has small amount of undershoot and overshoot at the price of rise time compared to the system without compensator. Also, provided the system is properly stable, the influence of the design parameter ${\alpha}$ on the step response of the nonminimum phase system is investigated in the case of Type A, and Type B undershoot, which gives a guideline for the compensator design.

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PERTURBATION OF WAVELET FRAMES AND RIESZ BASES I

  • Lee, Jin;Ha, Young-Hwa
    • Communications of the Korean Mathematical Society
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    • v.19 no.1
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    • pp.119-127
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    • 2004
  • Suppose that $\psi{\;}\in{\;}L^2(\mathbb{R})$ generates a wavelet frame (resp. Riesz basis) with bounds A and B. If $\phi{\;}\in{\;}L^2(\mathbb{R})$ satisfies $$\mid$\^{\psi}(\xi)\;\^{\phi}(\xi)$\mid${\;}<{\;}{\lambda}\frac{$\mid$\xi$\mid$^{\alpha}}{(1+$\mid$\xi$\mid$)^{\gamma}}$ for some positive constants $\alpha,{\;}\gamma,{\;}\lambda$ such that $1{\;}<1{\;}+{\;}\alpha{\;}<{\;}\gamma{\;}and{\;}{\lambda}^2M{\;}<{\;}A$, then $\phi$ also generates a wavelet frame (resp. Riesz basis) with bounds $A(1{\;}-{\;}{\lambda}\sqrt{M/A})^2{\;}and{\;}B(1{\;}+{\;}{\lambda}\sqrt{M/A})^2$, where M is a constant depending only on $\alpha,{\;}\gamma$ the dilation step a, and the translation step b.

Developmental Characteristics of SCNT Pig Embryos Knocked-out of Alpha-1,3-Galactosyltransferase Gene

  • Shim, Joo-Hyun;Park, Mi-Rung;Yang, Byoung-Chul;Ko, Yeoung-Gyu;Oh, Keon-Bong;Lee, Jeong-Woong;Woo, Jae-Seok;Park, Eung-Woo;Park, Soo-Bong;Hwang, Seong-Soo
    • Reproductive and Developmental Biology
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    • v.33 no.3
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    • pp.157-162
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    • 2009
  • This study was performed to comprehend the developmental characteristics of cloned embryos knocked out (KO) of $\alpha$-1,3-galactosyltransferase (GalT) gene. Immature oocytes were collected and cultured for 40 hrs (1-step) or 20hrs (with hormone) + 20hrs (without hormone) (2-step). The embryos transferred with miniature pig ear fibroblast cell were used as control. The reconstructed embryos were cultured in PZM-3 with 5% $CO_2$ in air at $38.5^{\circ}C$ for 6 days. To determine the quality of the blstocysts, TUNEL and quantitative realtime RT-PCR were performed. The embryos were transferred to a surrogate (Landrace) at an earlier stage of the estrus cycle. The maturation rate was significantly higher in 2-step method than that of 1-step (p<0.05). The blastocyst development of GalT KO embryos was significantly lower than that of normal cloned embryos (p<0.05). The total and apoptotic cell number of GalT KO blastocysts was not different statistically from control. The relative abundance of Bax-$\alpha$/Bcl-xl ratio was significantly higher in both cloned blastocysts than that of in vivo blastocysts (p<0.05). Taken together, it can be postulated that the lower developmental potential and higher expression of apoptosis related genes in GalT KO SCNT embryos might be a cause of a low efficiency of GalT KO cloned miniature pig production.

A Novel Synthetic Methods for $\alpha$-Amino Acids from Allyl Ethers via N-Allylcarbamates

  • jung, Young-Hoon;Kim, Ji-Deuk
    • Archives of Pharmacal Research
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    • v.23 no.6
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    • pp.574-578
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    • 2000
  • Protected $\alpha$-Phenyl glycine 17 and phenylalanine 18 and 19 have been synthesized through an efficient three-step sequence from the corresponding allyl ethers 5, 7, and 10. The key intermediate in this synthesis is the corresponding allylic amines prepared by reaction of allyl ethers with chlorosulfonyl isocyanate.

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A STUDY ON SIMPLE TIME VARYING FEEDFORWARD COMPENSATOR

  • Kwon, Byung-Moon;Son, Won-Kee;Kwon, Oh-Kyu
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.500-500
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    • 2000
  • In this paper, we deal wit,11 a simple tim varying feedforward compensator in order to decrease the amount of undershoots and overshoots on the step response. This compensator makes the step type input be a ramp input with saturation for 0 $\leq$ t < $\alpha$. It will be shown that the system with the feedforward compensator has small amount of undershoot and overshoot at the price of rise time. Also, provided the system properly stable, the influence of the design parameter $\alpha$ on the step response of the system with the feedforward compensator is investigated in the current paper.

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Determination of Reactivity by MO Theory (XXII). MO Studies of Substituent Effects of Rates of Phenylthiyl Radical Additions to ${\alpha}$-Methylstyrene (分子軌道論에 의한 反應性 決定 (제22보). ${\alpha}$-Methylstyrene 에 대한 Phenylthiyl Radical 부가반응에서의 치환기 효과에 관한 分子軌道論的 연구)

  • Ikchoon Lee;Young Gu Cheun
    • Journal of the Korean Chemical Society
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    • v.26 no.1
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    • pp.1-6
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    • 1982
  • The addition of thiophenol to ${\alpha}$-methylstyrene has been studied MO theoretically using CNDO/2 method. Although overall reaction proceeds in two steps i.e., (1) decomposition of thiophenol to give phenylthiyl radical and (2) addition of the radical to ${\alpha}$-methylstyrene to give a new monomer radical, theoretical results suggested that the phenylthiyl radical formation step, (1), was the dominant process in determining the rate of addition; this was the rationale behind the negative ${\rho}$ value obtained experimentally from the Hammett plots for substituents on the thiyl radicals. The departure from a linear Hammett plot for addition of ${\rho}$-chlorophenylthiyl and m-trifluoromethyl phenylthiyl to ${\rho}$-methoxy-${\alpha}$-methylstyrene could be explained as a result of an increased contribution of the addition step, (2) to the overall reaction rate.

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Error Estimation and Adaptive Time Stepping Procedure for Structural Dynamics (구조동역학에서의 오차 추정과 시간간격 제어 알고리즘)

  • 장인식
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.4
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    • pp.190-200
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    • 1996
  • Step-by-step time integration methods are widely used for solving structural dynamics problem. One difficult yet critical choice an analyst must make is to decide an appropriate time step size. The choice of time step size has a significant effect on solution accuracy and computational expense. The objective of this research is to derive error estimate for newly developed time integration method and develop automatic time step size control algorithm for structural dynamics. A formula for computing error tolerance is derived based on desired period resolution. An automatic time step size control strategy is proposed based on a normalized local error estimate for the generalized-α method. Numerical examples demonstrate the developed strategy satisfies general design criteria for time step size control algorithm for dynamic problem.

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Dynamic Economic Load Dispatch Problem Applying Valve-Point Balance and Swap Optimization Method (밸브지점 균형과 교환 최적화 방법을 적용한 동적경제급전문제)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.1
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    • pp.253-262
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    • 2016
  • This paper proposes a balance-swap method for the dynamic economic load dispatch problem. Based on the premise that all generators shall be operated at valve-points, the proposed algorithm initially sets the maximum generation power at $P_i{\leftarrow}P_i^{max}$. As for generator i with $_{max}c_i$, which is the maximum operating cost $c_i=\frac{F(P_i)-F(P_{iv_k})}{(P_i-P_{iv_k})}$ produced when the generation power of each generator is reduced to the valve-point $v_k$, the algorithm reduces i's generation power down to $P_{iv_k}$, the valve-point operating cost. When ${\Sigma}P_i-P_d$ > 0, it reduces the generation power of a generator with $_{max}c_i$ of $c_i=F(P_i)-F(P_i-1)$ to $P_i{\leftarrow}P_i-1$ so as to restore the equilibrium ${\Sigma}P_i=P_d$. The algorithm subsequently optimizes by employing an adult-step method in which power in the range of $_{min}\{_{max}(P_i-P_i^{min}),\;_{max}(P_i^{max}-P_i)\}$>${\alpha}{\geq}10$ is reduced by 10; a baby step method in which power in the range of 10>${\alpha}{\geq}1$ is reduced by 1; and a swap method for $_{max}[F(P_i)-F(P_i-{\alpha})]$>$_{min}[F(P_j+{\alpha})-F(P_j)]$, $i{\neq}j$ of $P_i=P_i{\pm}{\alpha}$, in which power is swapped to $P_i=P_i-{\alpha}$, $P_j=P_j+{\alpha}$. It finally executes minute swap process for ${\alpha}=\text{0.1, 0.01, 0.001, 0.0001}$. When applied to various experimental cases of the dynamic economic load dispatch problems, the proposed algorithm has proved to maximize economic benefits by significantly reducing the optimal operating cost of the extant Heuristic algorithm.

Study on Catalytic Activity of the Selective CO Oxidation and Characterization Using $La_{0.5}Ce_{0.5}Co_{1-x}Cu_xO_{3-{\alpha}}$ Perovskite Catalysts ($La_{0.5}Ce_{0.5}Co_{1-x}Cu_xO_{3-{\alpha}}$ Perovskite촉매의 선택적 CO 산화반응 및 특성 분석에 관한 연구)

  • Sohn, Jung-Min
    • Transactions of the Korean hydrogen and new energy society
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    • v.18 no.2
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    • pp.116-123
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    • 2007
  • [ $La_{0.5}Ce_{0.5}Co_{1-x}Cu_xO_{3-{\alpha}}$ ](X=0, 0.1, 0.3, 0.5) perovskites were prepared by coprecipitation method at pH 7 or pH 11 and its catalytic activity of selective CO oxidation was investigated. The characteristics of these catalysts were analyzed by $N_2$ adsorption, X-ray diffraction(XRD), SEM, $O_2$-temperature programmed desorption(TPD). The pH value at a preparation step made effect on particle morphology. The smaller particle was obtained with a condition of pH 7. The better catalytic activity was observed using catalysts prepared at pH 7 than pH 11. The maximum CO conversion of 98% was observed over $La_{0.5}Ce_{0.5}Co_{0.7}Cu_{0.3}O_{3-{\alpha}}$ at $320^{\circ}C$. Below $200^{\circ}C$, the most active catalyst was $La_{0.5}Ce_{0.5}Co_{0.9}Cu_{0.1}O_{3-{\alpha}}$, of which conversion was 92% at $200^{\circ}C$. By the substitution of Cu, the evolution of ${\alpha}$-oxygen was remarkably enhanced regardless of pH value at preparation step according to $O_2$-TPD. Among the different ${\alpha}$-oxygen species, the oxygen species evolved between $400^{\circ}C$ and $500^{\circ}C$, gave the better catalytic performance for selective CO oxidation including $La_{0.5}Ce_{0.5}CoO_3$ in which Cu was absent.

Development of Clinical evaluation tool for Nursing Students (임상간호교육 평가도구 개발)

  • Sung Myung-Sook;Jeong Geum-Hee;Jang Hee-Jung
    • The Journal of Korean Academic Society of Nursing Education
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    • v.4 no.2
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    • pp.172-186
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    • 1998
  • This study is intended to develop a reliable and approproate instrument of the clinical nursing education. This research consisted of 4 step. First step is contruction of the content for evaluation. Second step have the research of the content validity by 10 professors in Department of Nursing, H University, the pilot study for the content validity by 20 professors and clinical preceptors, and the survey with four point Likert Scale, which includes from the point of 'strongly valid' to the point of 'strongly non-valid' by 250 professor and clinical preceptor. The data were collected form March 1998 to July 1998. This study was analyzed by Cronbach's for the reliability and the factor analyisis for the validity of the collected data. The third step showed the final evaluation instrument of clinical nursing education which consists a couple of tool. One is the evaluation instrument of clinical nursing which includes the 20 items, the other is the evaluation instrument for case study which includes the 15 items. The fourth step is the test of reliability and validity of the final evaluation too. The results from these step's study showed the higher reliability and validity. Respectly, Cronbach's revealed the evaluation instrument of clinical nursing and case study is Cronbach's $\alpha$=.92413, Cronbach's $\alpha$=.95602. For further research, it needs to develop a reliable and variable instrument of the students self-evaluation and community based instrument.

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