• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.10
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• pp.4025-4041
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• 2020

Mobile edge computing (MEC) is capable of providing services to smart devices nearby through radio access networks and thus improving service experience of users. In this paper, an offloading strategy for the joint optimization of computing and communication resources in multi-user and multi-MEC overlapping scene was proposed. In addition, under the condition that wireless transmission resources and MEC computing resources were limited and task completion delay was within the maximum tolerance time, the optimization problem of minimizing energy consumption of all users was created, which was then further divided into two subproblems, i.e. offloading strategy and resource allocation. These two subproblems were then solved by the game theory and Lagrangian function to obtain the optimal task offloading strategy and resource allocation plan, and the Nash equilibrium of user offloading strategy games and convex optimization of resource allocation were proved. The simulation results showed that the proposed algorithm could effectively reduce the energy consumption of users.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.811-817
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• 2002

Gibbs ensemble Monte Carlo simulations were performed to calculate the vapor-liquid coexistence properties for the binary mixtures $CO_2/CH_3OH$, $CO_2/C_2H_5OH$, and $CO_2/CH_3CH_2CH_2OH.$ The configurational bias Monte Carlo method was used in the simulation of alcohol. Density of the mixture, composition of the mixture, the pressure-composition diagram, and the radial distribution function were calculated at vapor-liquid equilibrium. The composition and the density of both vapor and liquid from simulation agree considerably well with the experimental values over a wide range of pressures. The radial distribution functions in the liquid mixtures show that $CO_2$ molecules interact more stogly with methyl group than methylene group of $C_2H_5OH$ and $CH_3CH_2CH_2OH$ due to the steric effects of the alcohol molecules.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.865-872
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• 2002

A systematic way of determining the equilibrium orientation of carbon monoxide (CO) in heme proteins using time-resolved polarized mid-IR spectroscopy is presented. The polarization anisotropy at pump-probe delay time of zero in the limit of zero photolysis and the angular distrbution function of CO are required to obtain the equilibrium orientation of CO. An approach is developed for determining the polarization anisotropy in the zero-photolysis limit from the anisotropy measured under finite photolysis conditions in an optically thick sample where the fraction of molecules photolyzed decreased as the pump pulse passes through and is absorbed by the sample. This approach is verified by measuring the polarization anisotropy of CO of carbonmonoxy myoglobin at various levels of photolysis. This method can be readily applied to other photoselection experiments determining precise angle between transition dipoles.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.395-402
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• 1999

This paper discusses the theoretical researches subject to elastic buckling problems of the structures. The purpose is to ensure the characteristic of buckling be true by arc-length method and the finite element method. The difficulties in processes calculating the equilibrium curve after buckling is to get the equilibrium owe near singular point at which the determinant of stiffness matrix is zero. The purpose of the load-displacement curve is to determine the buckling load of the structure, and further to get the information about the characteristic after buckling. Here, this paper expresses the incremental solution at particular point by the linear combination of both homogeneous mode and particular mode, then uses the method which gets the unknown parameter including this function, through trial-and-error method including modified N-R convergence process. Finally, this paper describes the multiple bifurcation of truss dome as the numerical examples according to this algorithm.

• Management Science and Financial Engineering
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• v.19 no.1
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• pp.11-16
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• 2013

This paper derives an equilibrium asset price when there exist three kinds of traders in financial market: a risk-averse informed trader, noise traders, and risk neutral market makers. This paper is an extended version of Kyle's (1985, Econometrica) continuous time model by introducing insider's risk aversion. We obtain not only the equilibrium asset pricing and market depth parameter but also insider's value function and optimal insider's trading strategy explicitly. The comparative static shows that the market depth (the reciprocal of market pressure) increases with time and volatility of noise traders' trading.

• Journal of Biomedical Engineering Research
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• v.13 no.3
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• pp.235-244
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• 1992

In this paper, fluttering behavior of mechanical monoleaflet tilting disc heart valve prostheses during the opening phase was analyzed taking into consideration the impact between the occluder and the guiding strut at the fully open position. The motion of the valve occluder was modeled as a rotating system, and equations were derived by employing the moment equilibrium principle. Forces due to lift, drag, gravity and buoyancy were considered as external forces acting on the occluder. The 4th order Runge-Kutta method was used to solve the governing equations. The results iimonstrated that the occludes reaches steady equilibrium position only after damped vibration. Fluttering frequency varies as a function of time after opening and is in the range of 8-84 Hz. Valve opening appears to be affected by the orientation of the valve relative to gravitational force. The opening velocities are in the range of 0.65-1.42m/sec and the dynamic loads by impact of the occludes and the strut are in the range of 90-190 N.

• Journal of Biomedical Engineering Research
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• v.12 no.3
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• pp.149-156
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• 1991

In this paper, fluttering behavior of mechanical bileaflet heart valve prosthesis was analyzed taking into consideration of the impact between valve plate and stopper Vibration system of the valve was modeled as a rotating system, and equations are induced by moment equilibrium equations. Lift force, drag force, gravity and buoyancy were considered as external forces acting on the valve plate/ The 4th order Runge-Kutta method was used to solve the equations. Valve plate does not come to the static equilibrium position at a stretch, but come to that position after under damping vibration. Damping ratio increases as the cardiac optput increases, and the mean damping ratio is in the range of 0.16~40.25. Fluttering frequency does not have any specific value, but varies as a function of time. It is in the range of 10~40Hz. Valve opening appears to be affected by the orientation of the of the valve relative to gravitational forces.

• Journal of the Korean Applied Science and Technology
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• v.18 no.4
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• pp.249-253
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• 2001

A proposed method of determining the composition of mixed micelles in equilibrium with monomer of known composition is described. The systems were sodium ${\alpha}-sulfonated$ dodecanoyl ethyl esther (${\alpha}-SR_{12}Et$) or sodium dodecyl sulfate(SDS)-polyoxyethylene 23 lauryl ether (Brij 35) un water and in 0.1M sodium chloride solution at $25^{\circ}C$. This technique applies the Gibbs-Duhem equation to the mixed micelles, which is treated as a pseudophase. This proposed methodology, which needs only critical micelle concentration data as a function of monomer composition, is applied to an anionic/nonionic surfactant pair. The calculated monomer-micelle equilibrium is found to be very similar to the much-used regular solution for nonideal systems.

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.71-74
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• 1965

Reduction of Ti(Ⅳ)-oxalate complex on dropping mercury electrode has been studied as a function of oxalate concentration and of pH varied with HCl. Assuming there are equilibrium $TiO(C_2O_4)_2= \;+\;2H^+\;=\;Ti^{+4}\;+\;2C_2O_4\;=\;+\;H_2O,\;K_4$ in addition to $TiO(C_2O_4)_2\;^=\;=\;TiO^{++}\;+\;2C_2O_4=\;K_2\;Ti(C_2O_4)_2\;^-\;=\;Ti^{+3}\;+\;2C_2O_4=\;K_3$ in the system cathodic wave has been well explained for that pH is higher than 0.5. The equilibrium constants $K_2,\;K_3$ and $K_4$ have been to be $2{\times}10^{-12},\;5{\times}10^{-13}$ and $10^{-11}$, respectively. The reduction of Ti(Ⅳ)-oxalate system is $Ti^{+4}\;+\;e\;{\to}\;Ti^{+3}$ in the concentration of hydrochloric acid, higher than 3M.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.8
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• pp.720-725
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• 2001

Derivation of TSK fuzzy model from nonlinear differential equation is fundamental issue in the field of theoretical fuzzy control. The method which does not yield affine local differential equations at off-equilibrium points is proposed in this paper. A prototype TSK fuzzy model which has triangular membership functions for linguistic terms of the antecedent part is derived systematically. And then GA is used to modify the membership functions optimally. Simulation results show the validity of the proposed method.