• 제목/요약/키워드: Stabilizing effect

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Contents of $\beta$-Glucan in Various Cereals and Its Functional Properties

  • Whang, Key
    • Preventive Nutrition and Food Science
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    • 제3권4호
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    • pp.382-386
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    • 1998
  • A soluble dietary fiber, $\beta$-glucan, contained in oat and barley has nutritional benefits such as hypocholesterolemic effects and influences blood glucose regulation. The contents of $\beta$-glucan in both cereals range from 3 to 7% with the exception of a certain barley genotype which contains up to 16% $\beta$-glucan. $\beta$-Glucan is distributed mainly in the cell walls of endosperm and the distal (bran) portion of kernel. Various procedures have been developed for increasing the extraction yield of $\beta$-glucan. Oat gum prepared with weak alkali extractionand alcohol proecipitation following protein removal usually contains 80% $\beta$-glucan.The most commonly used method for $\beta$-glucan quantitiation is an enzymatic procedure combining lichenase plus $\beta$-glucosidase followed by measuring the amount of glucos released by glucose oxidase-peroxidase treatment. The increase in foam-and emulsion-stabilizing capacity of $\beta$-glucan is due to the increase in viscosity of the aqueous phase. Therefore, $\beta$-glucan shows great potentials as a thickener and a stabilizer.

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연속 냉간 압연기의 다변수 $H_{\infty}$ 외란제거 제어 (Multivariable $H_{\infty}$ disturbance rejection control for tandem cold mills)

  • 김승수;김종식
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.391-394
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    • 1997
  • A H$_{\infty}$ control techniques with roll eccentricity filter is proposed to alleviate the effect of entry thickness variation and roll eccentricity occurred in rolling stand itself of tandem cold mills. A robust controller to the disturbances is designed using H$_{\infty}$ control techniques, which can reflect the input direction of disturbances and knowledge of disturbance spectrum in the frequency domain. And, non-standard H$_{\infty}$ control problem caused by selection of weight function having poles on j.omega. axis is discussed. The evaluation for the resultant controller composed by H$_{\infty}$ synthesis is done through computer simulations. The effectiveness of the proposed method is compared to those of the conventional LQ synthesis method and a feedforward controller against roll eccentricity, which was already studied.ied.

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A study on the Convergence Condition of Chaotic Dynamic Neural Networks

  • Kim, Sang-Hee;Wang, Hua O.
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제7권4호
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    • pp.242-248
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    • 2007
  • This paper analyzes on the chaos characteristics of the chaotic neural networks and presents the convergence condition. Although the transient chaos of neural network sould be beneficial to overcome the local minimum problem and speed up the learning, the permanent chaotic response gives adverse effect on optimization problems and makes neural network unstable in general. This paper investigates the dynamic characteristics of the chaotic neural networks with the chaotic dynamic neuron, and presents the convergence condition for stabilizing the chaotic neural networks.

The Curvature and Shear Effects on the Eddy Viscosity

  • Lim, Hyo-Jae
    • 에너지공학
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    • 제8권2호
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    • pp.293-297
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    • 1999
  • Direct comparisons are made between curvature-corrected eddy viscosity models and the present experimental data. The results show that the curvature effects can be quantified through a curvature parameter R$\sub$c/ or S$\sub$c/ and a non-equilibrium value of p/$\varepsilon$. The data reveal a significant dependence of the eddy viscosity on the curvature and strain history for a fluid in a stabilizing curvature field, S$\sub$c/>1.0. Especially, experimental result shows that the eddy viscosity coefficient ratio at S$\sub$c/=3 changes from 10 to -10 although shear rate preserved constant. It is therefore suggested that proper curvature modifications, particularly the strain history effect, must be introduced into current eddy viscosity models for their application to turbulent flows subjected to curvature straining field for a non-negligible period of time.

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무전해 Co-Cu-P 도금속도에 미치는 도금 조건과 표면상태의 영향 (Effect of Plating Condition and Surface on Electroless Co-Cu-P Alloy Plating Rate)

  • 오이식
    • 동력기계공학회지
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    • 제4권2호
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    • pp.31-39
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    • 2000
  • Relationships between the plating condition and the plating rate of the deposition film for the electroless plating of Co-Cu-P alloy were discussed in this report. The result obtained from this experiment were summarized as follow ; The optimum bath composition was consisted of 0.8 ppm thiourea as a stabilizing agent. Composition of the deposit was found to be uniform after two hours of electroless plating. Plating rates of nickel-catalytic surface and zincate-catalytic surface were found to be very closely equal, but the plating time of nickel-catalytic surface took longer than that of the zincated-catalytic surface.

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Numerical study of the effect of periodic jet excitation on cylinder aerodynamic instability

  • Hiejima, S.;Nomura, T.
    • Wind and Structures
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    • 제5권2_3_4호
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    • pp.141-150
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    • 2002
  • Numerical simulations based on the ALE finite element method are carried out to examine the aerodynamics of an oscillating circular cylinder when the separated shear flows around the cylinder are stimulated by periodic jet excitation with a shear layer instability frequency. The excitation is applied to the flows from two points on the cylinder surface. The numerical results showed that the excitation with a shear layer instability frequency can reduce the negative damping and thereby stabilize the aerodynamics of the oscillating cylinder. The change of the lift phase seems important in stabilizing the cylinder aerodynamics. The change of lift phase is caused by the merger of the vortices induced by the periodic excitation with a shear layer instability frequency, and the vortex merging comes from the high growth rate, the rapid increase of wave number and decrease of phase velocity for the periodic excitation in the separated shear flows.

Effect of cement stabilization on geotechnical properties of sandy soils

  • Shooshpasha, Issa;Shirvani, Reza Alijani
    • Geomechanics and Engineering
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    • 제8권1호
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    • pp.17-31
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    • 2015
  • An experimental program was performed to study the effects of cement stabilization on the geotechnical characteristics of sandy soils. Stabilizing agent included lime Portland cement, and was added in percentages of 2.5, 5 and 7.5% by dry weight of the soils. An analysis of the mechanical behavior of the soil is performed from the interpretation of results from unconfined compression tests and direct shear tests. Cylindrical and cube samples were prepared at optimum moisture content and maximum dry unit weight for unconfined compression and direct shear tests, respectively. Samples were cured for 7, 14 and 28 days after which they were tested. Based on the experimental investigations, the utilization of cemented specimens increased strength parameters, reduced displacement at failure, and changed soil behavior to a noticeable brittle behavior.

SOI 소자에서의 바디 전압 안정화를 위한 실리콘 필름 Island 구조 (Stabilization of Body Bias Control in SOI Devices by Adopting Si Film Island)

  • 정인영;이종호;박영준;민홍식
    • 전자공학회논문지D
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    • 제36D권1호
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    • pp.100-106
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    • 1999
  • SOI MOSFET에서 바디 전압을 안정시키기 위하여 바디 저항과 콘택 소모면적을 줄이면서도 SOI 고유의 장점을 그대로 유지시키는 IBC(Island Body Contact) 구조를 창안하였다. 이 구조는 여러 MOSFEET 들의 바디를 서로 연결하여 같이 콘택을 형성함으로써 면적의 증가 없이 훌륭한 바디 콘택효과를 갖게 된다. VLSI 소자로서의 그 가능성을 소자 시뮬레이션과 제작된 소자와 회로의 측정실험을 통하여 확인하였다.

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케이블돔 구조물의 안정화 이행과정 및 구조적 거동특성에 관한 연구 (A Study on the Stabilizing Process and Structural Characteristics of Cable-Dome Structure)

  • 한상을;이경수;이주선;황보석
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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    • pp.260-267
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    • 1999
  • In this paper, We propose the initial shape finding and dynamic analysis of cable dome structure are presented. Cable dome that is consist of three component such as cable, strut and fabric membrane have complex structural characteristics. Main structural system of cable dome is cable-strut tensegric system, and fabric membrane element Is conceived as cladding roof material. One of the important problem of cable dome is shape finding of those subjected to cable and membrane forces, which stabilize the structures. And the other is structural response from external load effect such as snow and wind When cable dome are subjected to dynamic load such as wind load each structural component has many important problem because of their special structural characteristics. One problem is that geometrical nonlinearity should be considered in the dynamic analysis because large deformation is occurred from their flexible characteristic. The other problem is that wrinkling occurs occasionally because cable and membrane elements can not transmit compressive forces. So this paper describe the physical structural response of cable dome structure.

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