• Title/Summary/Keyword: Reaction parameter

검색결과 477건 처리시간 0.031초

효소반응 모델식에서의 매개변수 추정 (Parameter Estimation in Enzymatic Reaction Model)

  • 채희정;김지현차형준유영제
    • KSBB Journal
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    • 제5권2호
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    • pp.133-139
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    • 1990
  • 1회의 회분실험 데이터로부터 효소반응 속도식의 매개 변수를 쉽게 추정할 수 있는 방법을 제시하였다. 여러 가지 반응패턴을 갖는 모델식에 있어서 효소반응 데이터를 적용시킨 결과 정확하고 간편하게 매개변수값을 추정할 수 있었다. 가역반응의 경우에는 3개의 매개변수를 갖는 모델식의 형태로 평형 기질농도 및 매개변수를 추정할 수 있었다. 또한 반응특성이 잘 알려져 있지 않은 효소 반응 시스템에 있어서는 효소반응이 기질이나 생산물의 저해작용을 받는지 여부와 그 저해패턴을 확인할 수 있었다.

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Thermodynamic Analysis of the Hammett Reaction Parameter and Free Energy Relationship for the Pressure Change

  • Hwang, Jung-Ui
    • Bulletin of the Korean Chemical Society
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    • 제8권4호
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    • pp.237-242
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    • 1987
  • Pressure dependance of Hammett reaction parameter was analyzed and the free energy relationship for the pressure change derived thermodynamically. There are insufficient data in the literature to test the relation derived but from some limited previous data it could be concluded that the parameter ${\rho}$ is dependent on pressure and increase or decrease as pressure increase for a given reaction series.

야드형 AGV-서스펜션 파라미터의 최적화를 위한 충격하중 해석 (Analysis of Impact Load for Optimum of Suspension Parameter of Yard AGV)

  • 홍도관;김재헌;안찬우;전언찬;김중완
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2002년도 추계공동학술대회논문집
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    • pp.161-167
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    • 2002
  • Cai-go management facility of harbor are required an expansion due to increase of cargo quantity. Design technology of Yard AGV call be possible to deal many cargo rapidly and accurately. So it is produced a profit about cal-go management. This study is presented optimum of suspension parameter for design technology Yard AGV. Model I, II are modeled about Initial of container weight, height. When the maximum stroke of suspension is 0.26m, optimum is achieved to reduce the reaction force at the minimum. Also, the reaction force is study to become stability in I second. A change of spring constant and coefficient of damper make change the reaction force and minimum reaction force appear in optimum value. All modeling and analysis are used combination. contact element of Ansys program.

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Benzyl Chloride의 Chlorine 交換反應 (Kinetic Studies of Chlorine Exchange between Benzyl Chloride and Radioactive Chloride Ion)

  • 박용자;이익춘
    • 대한화학회지
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    • 제9권1호
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    • pp.23-28
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    • 1965
  • 90% ethanol solution에서 benzyl chloride와 radioactive chloride($^{36}Cl^-$)와의 exchange를 反應速度論的으로 硏究하였으며 그 結果로 交換反應은 typical bimolecular reaction임을 알았고 그 activation parameter들은 각기 다음과 같았다. ${\Delta}H^{\neq}$= 18.50 Kcal ${\Delta}S^{\neq}$= -22.09 e.u. 특히 本實驗 缺課와 다른 實驗結果를 綜合討論함으로써 反應速度는 attacking anion의 nuclephilic ability에 크게 관계 됨을 입증할 수 있었으며 또한 exchange reaction에 있어서 halide들의 reactivity의 순서는 bond dissociation energy의 差로써 보다는 오히려 Swain의 nucleophilic parameter(n)로써 설명함이 더욱 타당함을 알았다.

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Prediction of Solvent Effects on Rate Constant of [2+2] Cycloaddition Reaction of Diethyl Azodicarboxylate with Ethyl Vinyl Ether Using Artificial Neural Networks

  • Habibi-Yangjeh, Aziz;Nooshyar, Mahdi
    • Bulletin of the Korean Chemical Society
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    • 제26권1호
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    • pp.139-145
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    • 2005
  • Artificial neural networks (ANNs), for a first time, were successfully developed for the modeling and prediction of solvent effects on rate constant of [2+2] cycloaddition reaction of diethyl azodicarboxylate with ethyl vinyl ether in various solvents with diverse chemical structures using quantitative structure-activity relationship. The most positive charge of hydrogen atom (q$^+$), dipole moment ($\mu$), the Hildebrand solubility parameter (${\delta}_H^2$) and total charges in molecule (q$_t$) are inputs and output of ANN is log k$_2$ . For evaluation of the predictive power of the generated ANN, the optimized network with 68 various solvents as training set was used to predict log k$_2$ of the reaction in 16 solvents in the prediction set. The results obtained using ANN was compared with the experimental values as well as with those obtained using multi-parameter linear regression (MLR) model and showed superiority of the ANN model over the regression model. Mean square error (MSE) of 0.0806 for the prediction set by MLR model should be compared with the value of 0.0275 for ANN model. These improvements are due to the fact that the reaction rate constant shows non-linear correlations with the descriptors.

화학반응 공정에서의 공정조건 및 허용차설계 (Parameter and Tolerance Designs of the Chemical Reaction Process)

  • 안종석;윤원영
    • 품질경영학회지
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    • 제30권1호
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    • pp.97-117
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    • 2002
  • We apply Taguchi method to the process optimization problem of chemical reaction process, and some case studies are done to find out the way for cost reduction and quality improvement The parameter and tolerance designs of Taguchi mettled are done with operation data of a chemical process and we propose a procedure how to use and analyze the operation data to find the optimal process conditions and tolerance limits. In order to use the continuous values in experiment conditions, it is suggested how to determine the interval of each level by discrete values and to treat any missing values caused from discrete 4 levels.

EXISTENCE OF OPTIMAL SOLUTION AND OPTIMALITY CONDITION FOR PARAMETER IDENTIFICATION OF AN ECOLOGICAL SPECIES SYSTEM

  • LI CHUNFA;FENG ENMIN
    • Journal of applied mathematics & informatics
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    • 제18권1_2호
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    • pp.273-286
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    • 2005
  • Parameter identification problem of a three species (predator, mutualist-prey, and mutualist) ecological system with reaction-diffusion phenomenon is investigated in this paper. The mathematical model of the parameter identification problem is constructed and continuous dependence of the solution for the direct problem on the parameters identified is obtained. Finally, the existence of optimal solution and an optimality necessary condition for the parameter identification problem are given.

통합모델과 최적 경로설계를 통한 산업용 로봇 동적 매개변수 규명 (Optimal Excitation Trajectories for the Dynamic Parameter Identification of Industrial Robots by Using Combined Model)

  • 박경조
    • 동력기계공학회지
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    • 제12권2호
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    • pp.55-61
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    • 2008
  • This paper discusses the advantages of using Fourier-based periodic excitation and of combining internal and external models in dynamic robot parameter identification. Internal models relate the joint torques or forces with the motion of the robot; external models relate the reaction forces and torques on the bedplate with the motion data. This combined model allows to combine joint torque/force and reaction torque/force measurements in one parameter estimation scheme. This combined model estimation will yield more accurate parameter estimates, and consequently better predictions of actuator torque, which is shown by means of a simulated experiment on a CRS A465 industrial robot.

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Symmetrically loaded beam on a two-parameter tensionless foundation

  • Celep, Z.;Demir, F.
    • Structural Engineering and Mechanics
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    • 제27권5호
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    • pp.555-574
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    • 2007
  • Static response of an elastic beam on a two-parameter tensionless foundation is investigated by assuming that the beam is symmetrically subjected to a uniformly distributed load and concentrated edge loads. Governing equations of the problem are obtained and solved by pointing out that a concentrated edge foundation reaction in addition to a continuous foundation reaction along the beam axis in the case of complete contact and a discontinuity in the foundation reactions in the case of partial contact come into being as a direct result of the two-parameter foundation model. The numerical solution of the complete contact problem is straightforward. However, it is shown that the problem displays a highly non-linear character when the beam lifts off from the foundation. Numerical treatment of the governing equations is accomplished by adopting an iterative process to establish the contact length. Results are presented in figures to demonstrate the linear and non-linear behavior of the beam-foundation system for various values of the parameters of the problem comparatively.

냉각곡선 분석을 통한 편상흑연주철의 공정반응에 미치는 희토류원소 및 냉각속도의 영향 평가 (Evaluation of Effects of Rare Earth Element and Cooling Rate on the Eutectic Reaction of Flake Graphite Cast Irons by Cooling Curve Analysis)

  • 이상환;박승연;이상목;김명호
    • 한국주조공학회지
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    • 제33권1호
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    • pp.13-21
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    • 2013
  • The effects of rare earth element (R.E.) and cooling rate on the eutectic reaction of flake graphite cast irons were studied by combined analysis of macro/micro-structure and cooling curve data. The correlation between eutectic reaction parameter and macro/micro-structure was systematically investigated. Two sets of chemical compositions with the different addition of R.E. were designed to cast. Three types of molds for cylindrical specimens with the different diameters were prepared to analyze cooling rate effect. The difference between undercooling temperature and cementite eutectic temperature (${\Delta}T_1=T_{U}-T_{E,C}$), which is increased by adding R.E. and decreased by increasing cooling rate, is considered to be a suitable eutectic reaction parameter for predicting graphite morphology. According to the criterion, A-type graphite is mainly suggested to form for ${\Delta}T_1$ over $20^{\circ}C$. Eutectic reaction time (${\Delta}t$), which is decreased by adding R.E. or increasing cooling rate, is a suitable eutectic reaction parameter for predicting eutectic cell size. Eutectic cell size is found to decrease in a proportion to the decrease of ${\Delta}t$.