• Transactions of the Korean hydrogen and new energy society
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• v.28 no.5
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• pp.453-458
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• 2017

A study on the modeling of the methane Chemical Looping Reforming system was carried out. It is aimed to predict the temperature and concentration behavior of the product through modeling of oxygen carrier fixed bed reactors composed of multiple stacks. In order to design the reaction system, first of all, the flow rate of the hydrogen to be produced was calculated. The flow rate ratio of the oxidation/reduction reactor was calculated considering the heat of reaction between adjacent reactors. Finally, in this paper, kinetic model including empirical coefficients was suggested.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.590-595
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• 2004

Turbo fan as an air moving device is widely used for its silent characteristics and high efficiency relative to the other centrifugal multi blade impeller. In general, turbo fan is installed with a scroll casing for energy conversion from kinetic one to pressure energy. However, a turbo fan without scroll casing is considered as a present model that is proposed model for compact design of a product In detail, the model has only 4 cutoffs as guiders for 4 separated outlets. Specially, equal distribution of flow rate generated by the model blower is main interest in this investigation. The optimal position of the guider is found by reducing abnormal flows such as reverse flow in each outlet.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.807-811
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• 2002

We present a hypothetical quantum scattering model to propose a novel electroluminescence device. Adoping with features of solid state semiconductor LED and exciplex laser, the cathode (electrol incoming potential) and anode(electron outgoing potential) are made to correspond to two 1-dimensional resonance supporting potentials, and the light emitting part to an interaction potential in the intermediate region. When an external voltage is applied, the electron flows into the cathode having small work function. Subsequently in flows via LUMO of the " electron incoming potential" loses kinetic energy emitting a photon, then continues to flow via LUMO of the "electron outgoing potential" unlike the conventional LUMO to HOMO transitions occurring in solid state semiconductor LED. In this model, the photon frequency can be controlled by adijusting the applied voltage. The model hopefully could be realized as partially conjugated hydrocarbon chains.

• Korean Journal of Child Studies
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• v.21 no.4
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• pp.275-293
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• 2000

The study examined changes in mothers' perceptions about their families through group art therapy and group psychodrama. The 5 mothers selected as the experimental group were tested by Kinetic Family Drawing. The experimental group then participated in psychodrama This was a pre-test, 2 post-test experimental group only design. Each follow-up test was excused at 10 weeks after the previous test. Mothers' acting in the psychodrama was video-recorded. Subjects were interviewed to ascertain change in daily life after the psychotherapy. Results were that positive changes occurred in mothers regarding self-examination and understanding of their families. There were significant difference in the mothers' perceptions of themselves, their children and their families.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1269-1275
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• 2003

The quaternary carbon-containing alcohols (1-6) were resolved enantioselectively by various lipases such as PFL (Pseudomonas fluorescens lipase), LAK (Pseudomonas fluorescens lipase), CRL (Candida rugosa lipase) and PCL (Pseudomonas cepacia lipase). The enzymatic resolution of racemic alcohol $({\pm})-2$ gave the excellent enantioselectivity in favor of (S)-2d in 99% ee, while those of the racemic alcohols (1, 3, 4, 5 and 6) gave the resolved alcohols with moderate to good enantioselectivity. Also, their absolute configurations were determined by chemical transformation to the known compounds.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2913-2917
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• 2010

When rubber dissolved in toluene was used as a binding material of graphite powder, the mechanical robustness of the carbon paste was guaranteed by the fast volatility of the solvent immediately after electrode construction. This characteristic of the rubber solution met qualifications for practical use of carbon paste electrodes and enabled the design of a new enzyme electrode bound with EPDM. In order to confirm whether the electrode shows quantitative electrochemical behaviors or not, its kinetic parameters, e. g. the symmetry factor (0.2), the exchange current density ($3.66\;{\mu}A/cm^2$), the capacity of the double layer ($2.0{\times}10^{-5}\;F$), the Michaelis constant ($4.39{\times}10^{-3}\;M$), the diffusion coefficient of substrate ($2.58{\times}10^{-12}\;cm^2/sec$), the time constant (0.018 sec) and other factors were investigated.

• 유공압시스템학회:학술대회논문집
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• 2010.06a
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• pp.116-125
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• 2010

In this study, a novel hydraulic energy-regenerative system was presented from its proposal through its modeling to its control. The system was based on a closed-loop hydrostatic transmission and used a hydraulic accumulator as the energy storage system in a novel configuration to recover the kinetic energy without any reversion of the fluid flow. The displacement variation in the secondary unit was reduced, which widened the uses of several types of hydraulic pump/motors for the secondary unit. The proposed system was modeled based on its physical attributes. Simulation and experiments were performed to evaluate the validity of the employed mathematical model and the energy recovery potential of the system. The experimental results indicated that the round trip recovery efficiency varied from 22% to 59% for the test bench.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.4
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• pp.59-66
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• 2014

This paper deals with vibration of plates with concentrated mass on elastic foundation. The object of investigating natural frequencies of tapered thick plate on pasternak foundation by means of finite element method and providing kinetic design data for mat of building structures. Free vibration analysis that tapered thick plate in this paper. Finite element analysis of rectangular plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on pasternak foundation. The Winkler parameter is varied with 10, $10^2$, $10^3$ and the shear foundation parameter is 5, 10. This paper is analyzed varying thickness by taper ratio. The taper ratio is applied as 0.0, 0.25, 0.5, 0.75, 1.0. And the Concentrated Mass is applied as P1, Pc, P2 respectively.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.164-166
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• 1999

In this study, dynamic analysis of Linear DC motor has been performed. Dynamic characteristic is carried out from coupling the electrical circuit equation and mechanical kinetic equation. Trust constant and circuit parameters are obtained by FE analysis and static characteristic experiment. From the previous results, dynamic analysis is performed and the appropriateness of analysed result is verified by comparing with experimental result.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.4
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• pp.509-514
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• 2000

A numerical study has been performed to design duct parameters in the freezer of a domestic refrigerator. The visualization results of FDM analysis using the standard k-$\varepsilon$ model with inlet boundary conditions modelled in this paper show good agreements with the experimental ones in prediction overall flow characteristics. Dominant vortex flows are found in the left upper and right lower corners, while there exists large turbulent kinetic energy around the fan and right upper side of the fan. It, in turn, has effects on the performance and noise. It is recommended to locate the outlet far away from the fan in order to reduce the noise level.