• Title, Summary, Keyword: ${\mu}$-synthesis

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A study on the speed control system of medium - small size diesel engine by $\mu$-synthesis ($\mu$-synthesis 기법에 의한 중.소형 디젤기관의 속도 제어계에 관한 연구)

  • 양주호;변정환;정병건
    • Journal of the Korean Society of Marine Engineering
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    • v.21 no.1
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    • pp.82-87
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    • 1997
  • This paper presents a method about the modeling of the medium - small diesel engine for the speed control and designs the robust speed control system by the $\mu$-synthesis, which has good performance, in spite of the existence of model uncertainities and the external disturbance. We confirmed the validity of the proposed modeling method and the designed control system by $\mu$-synthesis through the experimental responses.

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THE EFFECT OF SODIUM FLUORIDE AND SODIUM ORTHOVANADATE ON OSTEOBLASTIC CELL LINE MC3T3-E1 CELLS (Sodium fluoride와 Sodium orthovanadate가 조골세포주 MC3T3-E1에 미치는 영향에 관한 연구)

  • Kim, Won-Jin;Chung, Kyu-Rhim
    • The korean journal of orthodontics
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    • v.21 no.1
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    • pp.97-111
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    • 1991
  • It is the aim of this study to investigate the effects of sodium fluoride and sodium orthovanadate upon the proliferation and activity of the osteoblast (MC3T3-E1 cells). MC3T3-E1 cells were cultured in $\alpha-MEM$ containing $10\%$ FBS and various concentration of sodium fluoride and sodium orthovanadate was appended to serum free media. DNA synthesis was examined through the $[^3H]$ thymidine incorporation into DNA. Collagen synthesis was examined through the $[^3H]$ proline incorporation into collagenase digestible protein and noncollagen protein. The following results were drawn; 1. Sodium fluoride stimulated the DNA synthesis of osteoblast significantly in dose-dependent manner within the concentration from $2{\mu}M$ to $10{\mu}M$ (P < 0.005). 2. Sodium orthovanadate stimulated the DNA synthesis of osteoblast significantly in dose-dependent manner within the concentration from $2{\mu}M\;to\;8{\mu}M$, however showed diminution at $10{\mu}M$ (P < 0.001). 3. Sodium fluoride and sodium orthovanadate stimulated the percent collagen synthesis of osteoblast significantly in dose-dependent manner within the concentration from $5{\mu}M$ to $10{\mu}M$ (P < 0.001). 4. Sodium fluoride and sodium orthovanadate stimulated the noncollagen synthesis of osteoblast significantly in dose-dependent manner within the concentration from $5{\mu}M\;to\;10{\mu}M$ (P < 0.001). In conclusion, sodium fluoride and sodium orthovanadate stimulate the proliferation and activity of osteoblast by stimulation of DNA synthesis and collagen and noncollagen synthesis in osteoblast.

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A study of design on model following ${\mu}-$synthesis controller for optimal fuel-injection (최적 연료주입 모델 추종형 ${\mu}-$합성 제어기의 설계에 관한 연구)

  • Hwang, Hyun-Joon;Kim, Dong-Wan;Jeong, Ho-Seong;Son, Mu-Hun;Kim, Yeung-Hun;Hwang, Gi-Hyun;Mun, Kyeong-Jun;Park, June-ho;Hwang, Chang-Sun
    • Journal of Institute of Control, Robotics and Systems
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    • v.4 no.2
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    • pp.163-169
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    • 1998
  • In this paper, we design an optimal model following ${\mu}-$synthesis control system for fuel-injection of diesel engine which has robust performance and satisfactory command tracking performance in spite of uncertainties of the system. To do this, we give gain and dynamics parameters to the weighting functions and apply genetic algorithm with reference model to the optimal determination of the weighting functions that are given by the D-K iteration method which can design ${\mu}-$synthesis controller in the state space. These weighting functions are optimized simultaneously in the search domain which guarantees the robust performance of the system. The ${\mu}-$synthesis control system for fuel-injection designed by the above method has not only the robust performance but also a better command tracking performance than those of the ${\mu}-$synthesis control system designed by trial-and-error method. The effectiveness of this ${\mu}-$synthesis control system for fuel-injection is verified by computer simulation.

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Mixed H$_2$$H^$\infty$$ and $\mu$-synthesis Approach to the Coupled Three-Inertia Problem (혼합 $H_2$/$H^$\infty$$$\mu$-설계이론을 이용한 3관성 문제의 해법)

  • Choe, Yeon-Wook
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.11
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    • pp.896-903
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    • 2001
  • This study investigates the use of mixed $H_2$/$H^$\infty$$ and $\mu$-synthesis to construct a robust controller for the benchmark problem. The model treated in the problem is a coupled three-inertial system that reflects the dynamics of mechanical vibrations. This kind of problem requires to be satisfied the robust performance (both in the time and frequency-domain specifications). We, first, adopt the mixed $H_2$/$H^$\infty$$ theory to design a feedback controller K(s). Next, $\mu$-synthesis method is applied to the overall system to make use of structured parametric uncertainty. This process permits higher levels of controller authority and reduces the conservativeness of the controller. Finally, the feedforward controller is also used to improve the transient response of the output. We confirm that all design specifications except a complementary sensitivity condition can be achieved.

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A Design on Model Following ${\mu}$-Synthesis Control System for Optimal Fuel-Injection of Diesel Engine Using Genetic Algorithms (유전 알고리즘을 이용한 디젤 엔진의 최적 연료주입 모델 추종형 ${\mu}$-합성 제어 시스템의 설계)

  • Kim, Dong-Wan;Hwang, Hyun-Joon
    • Proceedings of the KIEE Conference
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    • pp.587-589
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    • 1997
  • In this paper we design the model following ${\mu}$-synthesis control system for optimal fuel-injection of diesel engine using genetic algorithms. To do this, we give gain and dynamics parameters to the weighting functions and apply genetic algorithms with reference model to the optimal determination of weighting functions that are given by D-K iteration method which can design ${\mu}$-synthesis controller in the state space. These weighting functions are optimized simultaneously in the search domain selected adequately. The effectiveness of this ${\mu}$-synthesis control system for fuel-injection is verified by computer simulation.

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Mixed H$_2$H$\infty$and $\mu$-synthesis Approach to Coupled Three-Inertia Benchmark Problem (혼합 H$_2$H$\infty$$\mu$-이론을 이용한 벤치마크 문제의 해법)

  • 최연욱
    • 제어로봇시스템학회:학술대회논문집
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    • pp.22-22
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    • 2000
  • This study investigates the use of mixed $H_2/H_{\infty}$ and $\mu$-synthesis to construct a robust controller for the benchmark problem. The model treated in the problem is a coupled three-inertia system which reflects the dynamics of mechanical vibrations. We, first adopt the mixed $H_2/H_{\infty}$ the to design a feedback controller K(s). Next, $\mu$-synthesis method is applied to the overall system to make use of structured parametric uncertainty.

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Effects of the Protein Fraction of Panax ginseng on Primary Cultured Chicken Brain Cells and DRG (인삼 단백분획물이 일차배양한 계배의 뇌세포 및 DRG에 미치는 영향)

  • Park, Mi-Jung;Song, Jin-Ho;Kim, Sun-Yeou;Kim, Young-Choong
    • YAKHAK HOEJI
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    • v.34 no.5
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    • pp.365-373
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    • 1990
  • The effects of the protein fraction of Panax ginseng on primary cultured chicken embryonic brain cells and DRG cultured with a deficient medium were studied. The protein fraction was further fractionated into four groups according to the molecular weight; larger than 10,000 dalton(fraction A), between 5,000 and 10,000 daltons(fraction B), between 1,000 and 5,000 daltons(fraction C), between 500 and 1,000 daltons(fraction D). All four protein fractions at the concentration of $100\;{\mu}g/ml$ significantly increased the number of the brain cells which promoted the neurite outgrowth. The activity of PDHC in the brain cells was elevated significantly by the protein fraction B at the concentration of $100\;{\mu}g/ml$. It was noted that $100\;{\mu}g/ml$ protein fraction C and D significantly enhanced the synthesis of protein in the brain cells. At the concentration of $100\;{\mu}g/ml$, the protein fraction B enhanced RNA synthesis and the protein fraction A significantly enhanced DNA synthesis in the brain cells. The protein fractions B, C, and D significantly promoted the neurite outgrowth of DRG at the concentration of $100\;{\mu}g/ml$.

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Antitumor Activity of Crude Sesaminol in Sesame Seed

  • Ryu, Su-Noh;Lee, Bong-Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.43 no.3
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    • pp.168-171
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    • 1998
  • Sesaminol in sesame seed was postulated to have antitumor activity. The present study was performed to characterize the role of crude sesaminol extracted from sesame seed (Sesame Crude Sesaminol; SCS) on inhibiting the in vitro growth of human leukemia HL-60 cells. SCS inhibited the growth of human leukemia HL 60 cells in culture and macromolecular synthesis in a dose and time dependent manner. The cytostatic range of SCS concentration was found to be 60 to 100 $\mu\textrm{g}$/ml. SCS concentration greater than 200 $\mu\textrm{g}$/mlwere cytocidal to HL-60 cells. When SCS concentraction was 6 $\mu\textrm{g}$/mland 50 $\mu\textrm{g}$/ml the synthesis of HL-60 cells was inhibited by 35% for DNA, 6% for RNA and 5% for protein and 83% for DNA, 76% for RNA and 60% for protein. Of specific interest was the irreversible effect of SCS in inhibiting DNA synthesis of HL-60 cells. This was evidenced from the fact that, even after washed with PBS three times, preincubated HL-60 cells still showed the inhibited DNA synthesis.

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The μ-synthesis and analysis of water level control in steam generators

  • Salehi, Ahmad;Kazemi, Mohammad Hosein;Safarzadeh, Omid
    • Nuclear Engineering and Technology
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    • v.51 no.1
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    • pp.163-169
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    • 2019
  • The robust controller synthesis and analysis of the water level process in the U-tube system generator (UTSG) is addressed in this paper. The parameter uncertainties of the steam generator (SG) are modeled as multiplicative perturbations which are normalized by designing suitable weighting functions. The relative errors of the nominal SG model with respect to the other operating power level models are employed to specify the weighting functions for normalizing the plant uncertainties. Then, a robust controller is designed based on ${\mu}$-synthesis and D-K iteration, and its stability robustness is verified over the whole range of power operations. A gain-scheduled controller with $H_{\infty}$-synthesis is also designed to compare its robustness with the proposed controller. The stability analysis is accomplished and compared with the previous QFT design. The ${\mu}$-analysis of the system shows that the proposed controller has a favorable stability robustness for the whole range of operating power conditions. The proposed controller response is simulated against the power level deviation in start-up and shutdown stages and compared with the other concerning controllers.

Calcium-Boron Interaction in Exopolysaccharide Production by the Cyanobacterium, Nostoc spongiaeforme

  • Singh;Netu;Asthana, R.K.;Singh, S.P.
    • Journal of Microbiology and Biotechnology
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    • v.10 no.3
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    • pp.381-385
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    • 2000
  • The effect and interaction of Ca and B on exopolysaccharide (EPS) synthesis in the diazotrophically growing cyanobacterium. Nostoc spongiaeforme, was investigated. The absence of B inhibited EPS synthesis 1.56-fold ($16\mu\textrm{g}$ glucose equivalent/mg dry weight, 16 d) over the control cells ($25\mu\textrm{g}$ glucose equivalent) grown in medium containing 0.5 mM Ca and $8{\mu}{\textrm}{m}$ B. When B concentration was raised to $40{\mu}{\textrm}{m}$, EPS production was stimulated 1.8-fold. Reduction of Ca concentraion to one-half (0.25 mM) resulted in increased B demand (16$\muM$) by the cells for EPS production at par with the normal sets. However, without Ca, EPS production also increased as B increased. Addition of B to a Ca-free medium stimulated cyanobacterial diazotrophic growth as well as synthesis of Chl a and phycocyanin (0-8 d). The data suggest B-dependent diazotrophic growth during Ca-deficiency and point to and important interactive role of Ca and B in regulation of cyanobacterial EPS synthesis.

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