• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.409-414
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• 1996

Radionuclides such as Cs and Sr were removed from dilute aqueous solutions by means of inorganic adsorbents, 13X and chabazite. The physical adsorption obeyed the DA equation and non-equilibrium dynamic adsorption model, which describes surface diffusion mechanism with the DA equation, simulated the adsorption behavior of cesium and strontium on zeolite in fixed bed adsorbers. The dynamic model simulated the adsorption behavior of cesium and strontium.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.3
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• pp.342-347
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• 2007

The research on production and application of hydrogen as an alternative energy in the future is being carried out actively. It hydrogen storage is necessary in order that user use hydrogen economically without much difficulty. Among the ways of hydrogen storage the method which is compressed hydrogen gas by high pressure is easier for application than other methods. In this study, we have been calculated gas with changing pressure and temperature variation of container wall through applied to mass and energy balance equation when compressing hydrogen by high pressure, and also to Beattie-Bridgeman equation of state for the kinetic of hydrogen. We will apply above date as a preliminary for design of hydrogen storage tank.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05c
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• pp.194-198
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• 2002

Energy Distribution Function in pure $CH_4$, $CF_4$ and mixtures of $CF_4$ and Ar, have been analyzed over a range of the reduced electric field strength between 0.1 and 350[Td] by the two-tenn approximation of the Boltzmann equation (BEq.) method and the Monte Carlo simulation (MCS). The results of the Boltzmann equation and the Monte Carlo simulation have been compared with the data presented by several workers. The deduced transport coefficients for electrons agree reasonably well with the experimental and simulation data obtained by Nakamura and Hayashi. The energy distribution function of electrons in $CF_4-Ar$ mixtures shows the Maxwellian distribution for energy. That is, f(${\varepsilon}$) has the symmetrical shape whose axis of symmetry is a most probably energy

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.169-174
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• 1996

In this paper, the electron transport characteristic in CF$_4$has been analysed over the E/N range 1~300(Td) by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The alteration of cross sections from the literature is avoided as much as possible in the analysis. The motion has been calculated to give swarm parameters for the electron drift velocity(W), diffusion coefficient(D$_{L}$), the ratio of the diffusion coefficient to the mobility(D$_{L}$/$\mu$), mean energy($\varepsilon$), the electron energy distribution function. The electron energy distribution function has been analysed in CF$_4$at E/N=50, 100 and 200(Td) for a case of the equilibrium region in the mean electron energy. The results of Boltzmann equation and Monte Carlo simulation have been compared with experimental data by Y. Nakamura and M. Hayashi.shi.

• Bulletin of the Korean Chemical Society
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• v.18 no.2
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• pp.171-174
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• 1997

The initial kinetic energy of laser-ablated Zn cation has been investigated via time-of-flight mass spectrometry. The flight times of the ions have been measured with a high voltage pulse on the extract electrode in the mass spectrometer, which has been delayed from the laser pulse. The time-of-flight equation including the initial kinetic energy term of the ion has been derived for the mass spectrometer. The optimum value of the initial kinetic energy has been extracted by fitting the measured flight times into the time-of-flight equation. The initial kinetic energy of the ions generated by Nd:YAG laser (532 nm) at the power density of 5 × 107 W/cm2 has been determined to be 22-44 kJ/mol.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.4
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• pp.615-622
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• 2020

Objective: The objectives were to investigate correlations between energy digestibility (digestible energy [DE]:gross energy [GE]) and various fiber types including crude fiber (CF), total dietary fiber (TDF), soluble dietary fiber (SDF), insoluble dietary fiber (IDF), neutral detergent fiber (NDF), and acid detergent fiber (ADF), and to develop prediction equations for estimating DE in feed ingredients and diets for growing pigs. Methods: A total of 289 data with DE values and chemical composition of feeds from 39 studies were used to develop prediction equations for DE. The equations were validated using values provided by the National Research Council. Results: The DE values in feed ingredients ranged from 2,011 to 4,590 kcal/kg dry matter (DM) and those in diets ranged from 2,801 to 4,203 kcal/kg DM. In feed ingredients, DE:GE was negatively correlated (p<0.001) with NDF (r = -0.84), IDF (r = -0.83), TDF (r = -0.82), ADF (r = -0.78), and CF (r = -0.72). A best-fitting model for DE (kcal/kg) in feed ingredients was: 1,356 + (0.704 × GE, kcal/kg) - (60.3 × ash, %) - (27.7 × NDF, %) with R² = 0.80 and p<0.001. In diets, DE:GE was negatively correlated (p<0.01) with NDF (r = -0.72), IDF (r = -0.61), TDF (r = -0.52), CF (r = -0.45), and ADF (r = -0.34). A best-fitting model for DE (kcal/kg) in diets was: 1,551 + (0.606 × GE, kcal/kg) - (22.1 × ash, %) - (25.6 × NDF, %) with R² = 0.62 and p<0.001. All variables are expressed as DM basis. The equation developed for DE in feed ingredients had greater accuracy than a published equation for DE. Conclusion: All fiber types are reasonably good independent variables for predicting DE of swine feeds. The best-fitting model for predicting DE of feeds employed neutral detergent fiber as an independent variable.

• Journal of the Korean Solar Energy Society
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• v.36 no.5
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• pp.63-71
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• 2016

Installed PV module in field is affected by shading caused by various field environmental factors. Bypass diodes are installed in PV module for preventing a power loss and degradation of PV module by shading. But, Bypass diode is easily damaged by surge voltage and has often initial a defect. This paper propose the electric characteristic variation and the power prediction of PV module with damaged bypass diode. Firstly, the resistance for normal bypass diode and damaged bypass diode of resistance was measured by changing the current. When the current increases, the resistance of normal bypass diode is almost constant but the resistance of damaged bypass diode increases. Next, To estimate power of PV module by damaged bypass diode, the equation for the current is derived using solar cell equivalent circuit. Finally, the derived equation was simulated by using MatLab tools, was verified by comparing experimental data.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05c
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• pp.43-46
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• 2004

This paper describes the information for quantitative simulation of weal이y ionized plasma. We must grasp the meaning of the plasma state condition to utilize engineering application and to understand materials of plasma state. Using quantitative simulations of weakly ionized plasma, we can analyze gas characteristic. In this paper, the electron transport characteristic in $CH_4$ has been analysed over the E/N range 0.1~300[Td], at the $300[_{\circ}K]$ by the two tenn approximation Boltzmann equation method and Monte Carlo Simulation. Boltzmann equation method has also been used to predict swarm parameter using the same cross sections as input. The behavior of electron has been calculated to give swarm parameter for the electron energy distribution function has been analysed in $CH_4$ at E/N=10, 100 for a case of the equilibrium region in the mean energy. The result of Boltzmann equation and Monte Carlo Simulation has been compared with experimental data by Ohmori, Lucas and Carter. The swarm parameter from the swarm study are expected to sever as a critical test of current theories of low energy scattering by atoms and molecules.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.146-146
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• 2018

Basin evapotranspiration is the result of water balance and energy balance, which is affected by climate and underlying surface characteristics, the process is complex, and spatial and temporal variability is large, the evapotranspiration estimation of river basin is an important but difficult problem in the field of hydrology, over the years, many scholars devoted to the basin actual evapotranspiration estimation and achieved excellent results. We discuss Budyko coupled water-energy balance theory and evaporation paradox, then use the Fu's equation to estimate actual evapotranspiration yearly in different areas with different dryness. The result shows that Fu's equation has high precision for estimating evapotranspiration yearly in our selected study area, and the estimation result has higher precision in the area with high dryness. Then, we propose an improved formula which can be used to estimate actual evapotranspiration monthly. Furthermore, we found that the parameter in the formula reflects general conditions of underlying surface and it is affected by several factors, at last, we tried to propose the calculation formula. The study indicates that Fu's equation provides a reliable method for evapotranspiration estimation in dry regions as well as semi-humid and semi-arid regions, which has great significance for forecasting river basin water resources and inquiring into ecological water requirement.

• Communications of the Korean Mathematical Society
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• v.32 no.3
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• pp.579-600
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• 2017

In this paper we consider a semilinear pseudoparabolic equation with polynomial nonlinearity and infinite delay. We first prove the existence and uniqueness of weak solutions by using the Galerkin method. Then, we prove the existence of a compact global attractor for the continuous semigroup associated to the equation. The existence and exponential stability of weak stationary solutions are also investigated.