• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.1018-1021
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• 1988

This study is concerned with modeling an elastomer constitutive relation by utilizing the truncated Volterra series. Actual experimental data from the Instron Tester are obtained for combined input, i.e. constant strain rate followed by a constant strain input. These data are then estimated for step inputs and utilized for the truncated Volterra series models. One second order and one third order truncated Volterra series models have been employed to estimated the force-displacement relation which is one of the prominent properities to characterize the viscoelastic material. The third order Volterra series model has better results, compared with those of the second order Volterra series model.

• Bulletin of the Korean Chemical Society
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• v.8 no.5
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• pp.408-414
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• 1987

The rate of bromine-exchange reaction between antimony tribromide and ${\alpha}-phenyl-n-butyl$ bromide in nitrobenzene has been determined, using antimony tribromide labelled with Br-82. The results indicate that the exchange reaction follows the first-order kinetics with respect to the organic bromide, and either the second- or first-order kinetics with respect to antimony tribromide depending on its concentration. The third-order rate constant obtained was 7.50 ${\times}10^{-2}l^2mol^{-2}s^{-1}$ at 28$^{\circ}$C. Similar study on the bromine-exchange reaction between antimony tribromide and ${\alpha}$-phenyl-i-butyl bromide has also been carried out. The results of the study show the same kinetic orders as the ones observed with $\alpha$-phenyl-n-butyl bromide. The third-order rate constant observed was 2.40 ${\times} 10^{-2} l^2mol^{-2}s^{-1}$ at 28$^{\circ}$C. The activation energy, the enthalpy of activation and the entropy of activation for the two exchange reactions mentioned above have been determined. The reaction mechanisms for the exchange reactions are discussed.

• Journal of the Korean Chemical Society
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• v.35 no.2
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• pp.111-118
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• 1991

The kinetic of the gas phase reactions of ozone(0.5 torr) with sulfur dioxide was studied. The SO2 reaction was conducted in the 7∼22 torr range at 90∼155$^{\circ}$C. The reaction rate was faster than the reaction rate of O$_3$ in the presence of CO$_2$ alone. The reaction of O$_3$ with SO$_2$ follows the rate law: -d(O$_3)/dt=k_0(SO_2)(M)(O_3)+2k _1(SO_2)(O_3$). The first term of this rate law arises from a third order molecular reaction predominating in the lower temperature range and gave a rate constant k$_0$ = (9.35 $\pm$ 8.6) ${\times}$ 10$^9$e$^{-(11.05{\pm}2.04)kcal/RT}(M^{-2}s^{-1}$). The second term of the above rate law derived from a second order thermal decomposition reaction which was the major part of the reaction and gave a rate constant k$_0 =(9.35{\pm}8.6){\times}10^9e^{-(11.05{\pm}2.04)kcal/RT}(M^{-2}s^{-1}$). The overall reaction proceeds with kinetics of complex order composed mainly of second order and third order components.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.6
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• pp.71-78
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• 1989

The imput-output relations for nonlinear systems can be explicitly represented by the Volterra series and they can be characterized by the Volterra kernels. This study is concerned with modeling an elastomer force-displacement relation due to step inputs by utilizing the truncated Volterra series. Since it is practically impossible to apply step inputs that have infinite slope at zero time, the loads due to constant penetration(displacement) rate followed by constant penetration inputs are measured as an alternative approach and estimated for step inputs and then utilized for the truncated Volterra series models. One second order and one third order truncated Volterra series models have been employed to model the force-displacement relation which is one of the prominent properties to characterize the viscoelastic material. The third order truncated Volterra series model has better results, compared with those of the second order truncated Volterra series model.

• Bulletin of the Korean Chemical Society
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• v.2 no.4
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• pp.138-141
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• 1981

The rate of the bromine-exchange reaction between gallium bromide and i-butyl bromide in 1,2,4-trichlorobenzene or nitrobenzene was measured at 19, 25 and $40^{\circ}C$, using i-butyl bromide labelled with Br-82. The results indicated that the exchange reaction was second order with respect to gallium bromide and first order with respect to i-butyl bromide. The third-order rate constant determined at $19{\circ}C$ was $3.28{\times}10^{-2}l^2{\cdot}mole^{-2}{\cdot}sec^{-1}$ in 1,2,4-trichlorobenzene and $9.25{\times}10^{-3}l^2{\cdot}mole^{-2}{\cdot}sec^{-1}$ in nitrobenzene. The activation energy, the enthalpy of activation and the entropy of activation for the exchange reaction were also determined.

• Bulletin of the Korean Chemical Society
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• v.2 no.3
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• pp.86-89
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• 1981

The rate of the bromine-exchange reaction between gallium bromide and n-propyl bromide in 1,2,4-trichlorobenzene and in nitrobenzene was measured at 19, 25 and $40^{\circ}C$, using n-propyl bromide labelled with Br-82. The results indicated that the exchange reaction was second order with respect to gallium bromide and first order with respect to n-propyl bromide. The third-order rate constant determined at $19^{\circ}C$ is $2.9{\times} 10^{-2}l^2{\cdot}mole^{-2}{\cdot}sec^{-1}$ in 1,2,4-trichlorobenzene and $4.5{\times}10^{-3}l^2{\cdot}mole^{-2}{\cdot}sec^{-1}$. in nitrobenzene. The activation energy, the enthalpy of activation and the entropy of activation for the exchange reaction were also determined. Reaction mechanism for the bromine exchange of n-propyl bromide seemed to be similar to those observed in earlier studies with other alkyl bromides.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.51-56
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• 2014

The solvolysis rate constants of 2,4-dimethoxybenzenesulfonyl chloride (1) in 30 different solvents are well correlated with the extended Grunwald-Winstein equation, using the $N_T$ solvent nucleophilicity scale and $Y_{Cl}$ solvent ionizing scale, with sensitivity values of $0.93{\pm}0.14$ and $0.65{\pm}0.06$ for l and m, respectively. These l and m values can be considered to support a $S_N2$ reaction pathway. The activation enthalpies (${\Delta}H^{\neq}$) were 12.4 to $14.6kcal{\cdot}mol^{-1}$ and the activation entropies (${\Delta}S^{\neq}$) were -15.5 to -$32.3kcal{\cdot}mol^{-1}{\cdot}K^{-1}$, which is consistent with the proposed bimolecular reaction mechanism. The solvent kinetic isotope effects (SKIE) were 1.74 to 1.86, which is also in accord with the $S_N2$ mechanism and was possibly assisted using a general-base catalysis. The values of product selectivity (S) for solvolyses of 1 in alcohol/water mixtures was 0.57 to 6.5, which is also consistent with the proposed bimolecular reaction mechanism. Third-order rate constants, $k_{ww}$ and $k_{aa}$, were calculated from the rate constants ($k_{obs}$), together with $k_{aw}$ and $k_{wa}$ calculated from the intercept and slope of the plot of 1/S vs. [water]/[alcohol]. The calculated rate constants, $k_{calc}$ ($k_{ww}$, $k_{aw}$, $k_{wa}$ and $k_{aa}$), are in satisfactory agreement with the experimental values, supporting the stoichiometric solvation effect analysis.

• Journal of the Korean Chemical Society
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• v.22 no.5
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• pp.281-288
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• 1978

Pseudo-first order rate constants $k_{obs}$ were determined for the reactions of naphthalenesulfonyl chlorides (1-NSC and 2-NSC) and anilines. The second order rate constant $k_2$ and third order catalytic $k_3$ were then determined from $k_{obs}$. For 1-NSC peri-hydrogen effect was observed. The large Brønsted ${\beta}$ and large negative slopes ${\rho}$ for the Hammett plots were obtained. These results with the unsually low values of activation parameters were consistent with the $S_AN$-elimination mechanism, but these can be equally well interpreted with the associative $S_N2$mechanism.

• Journal of the Korean Chemical Society
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• v.14 no.1
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• pp.85-89
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• 1970

The rate of the bromine-exchange reaction between gallium bromide and isopropyl bromide in nitrobenzene was measured at 19$^{\circ},\;25^{\circ}$ and 40$^{\circ}C$., using isopropyl bromide labelled with Br-82. The results indicated that the exchange reaction was second order with respect to gallium bromide and first order with respect to isopropyl bromide. The third-order rate constant determined at 19$^{\circ}C$. was 3.2 ${\times}10^{-2}l^2{\cdot}mole^{-2}sec^{-1}$. The activation energy, the enthalpy of activation and the entropy of activation for the exchange reaction were also determined.

• Korean Journal of Applied Biomechanics
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• v.17 no.4
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• pp.157-167
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• 2007

The purpose of this study was to analyze kinematic techniques in the woman's 100m hurdle. In order to find the kinematic parameters, a 3-D video system for kinematic analysis-kwon3d 3.1(Kwon3D Motion Analysis Program Version 3.1)-was used. Eight JVC video cameras(GR-HD1KR) were used to film the performance of Lee Yeon-Kyoung at a frame rate of 60fields/s. The kinematic characteristics from the first hurdle to last hurdle were analyzed at the clearing hurdle spots such as distance, velocities, heights and angles. The real-life three-dimensional coordinates of 20 body landmarks during each phases were collected using a Direct Linear Transformation procedure. After analyzing the kinematic variables in the 100m hurdle run, the following conclusion were obtained; Lee Yeon-Kyoung had to maintain constant stride lengths between hurdles and increase takeoff distance before clearance and shorter landing distance after clearance. She also had to hit the correct takeoff point in front of the hurdle and extend the lead leg at the moment of landing in order to minimize the loss of velocity. She had to sprint between hurdles as fast as possible over 8m/s and run powerful first stride and shortened third stride preparing for the following hurdle clearances.