• Title/Summary/Keyword: Reaction parameter

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

  • 채희정;김지현차형준유영제
    • KSBB Journal
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    • v.5 no.2
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    • pp.133-139
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    • 1990
  • A simple and convenient method was introduced to determine the kinetic parameters for various enzymatic reaction kinetics. The method based on integrated formular can be applied to the parameter estimations from a single experiment. A modified three-parameter model was applied for the parameter estimation in reversible reaction and the equilibrium substrate concentration could be also estimated. It is possible to identify the enzymatic reaction pattern by inspecting the parameter values and the square of the correlation coefficient.

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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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    • v.8 no.4
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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.

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

  • 홍도관;김재헌;안찬우;전언찬;김중완
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2002.11a
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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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Kinetic Studies of Chlorine Exchange between Benzyl Chloride and Radioactive Chloride Ion (Benzyl Chloride의 Chlorine 交換反應)

  • Park, Yong-Ja;Lee, Ik-Choon
    • Journal of the Korean Chemical Society
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    • v.9 no.1
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    • pp.23-28
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    • 1965
  • Halogen exchanges between benzyl chloride and chloride ion have been studied in 90% ethanol-water mixture, and activation parameters in the exchange reaction have been determined; ${\Delta}H^{\neq}$ = 18. 50 Kcal and ${\Delta}S^{\neq}$ = -22. 09 e. u. Results indicated that the reaction proceeded via a typical bimolecular mechanism. The importance of nucleophilic ability of attacking anion in $S_N2$ process has been stressed giving some experimental evidence. The order of reactivity of halides in the exchange reaction is better explained with the Swain's nucleophilic parameter than with the bond dissociation energies.

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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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    • v.26 no.1
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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.

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

  • 안종석;윤원영
    • Journal of Korean Society for Quality Management
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    • v.30 no.1
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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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    • v.18 no.1_2
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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.

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

  • Park, K.J.
    • Journal of Power System Engineering
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    • v.12 no.2
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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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    • v.27 no.5
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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.

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

  • Lee, Sang-Hwan;Park, Seung-Yeon;Lee, Sang-Mok;Kim, Myung-Ho
    • Journal of Korea Foundry Society
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    • v.33 no.1
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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 ${\Delta}t$.