• Journal of Biosystems Engineering
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• v.22 no.4
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• pp.433-438
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• 1997

The freshness of apple was evaluated by characterizing the surface texture of flesh cells. The freshness index which was related to the amount of wrinkles on the cell surface was defined to quantify the freshness. Four parameters relevant to the amount of the cell wrinkles were selected and measured using image analysis including wrinkle extraction procedure and Fast Fourier Transform of a wrinkle-extracted image. Out of 4 parameters, three parameters had highly significant correlations with the time elapsed after harvest. But it was concluded that two parameters out of such 3 parameters could be used for description of freshness index.

• Solar Energy
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• v.5 no.2
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• pp.54-59
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• 1985

Due to the grainboundary recombination and the poor diffusion length, the polycrystalline cell efficiency is lower than the singlecrystalline cell. In order to define the effect of grains and grain-boundaries, 2 - dimensional differential diffusion equations of minority carrier are modelled. To solve them, two theoretical formulas are derived, which can be evaluated the grainboundary recombination velocity and the grain diffusion length. Also computer-aided numerical analysis is given.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.77-77
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• 2003

Gene expression in a cell is regulated by mutual activations or repressions between genes. Identifying the gene regulation network will be one of the most important research topics in the post genomic era. We propose a linear dynamic model of gene regulation for the yeast cell cycle. A small gene network consisting of about 40 genes is reconstructed from the analysis of micro-array gene expression data of yeast S. cerevisiae published by P. Spellman et al. We show that the network construction is consistent with the result of the hierarchical cluster analysis.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.2 no.1
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• pp.37-45
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• 1991

The electromagnetic field distribution within rectangular coaxial transmission lines (RCTL:TEM cells) is calculated using a numerical method. Boundary integral equations(BIE) considering equivalence theorem and extended boundary condition(EBC) in tapered region are used, thereby restricting the operational frequencies (0~130 MHz) below the cell cutoff frequency(130 MHz). The EM fields within NIST TEM cell ($1\times0.6\times2m$) are calculated by this method. The results of the numerical calcuation have a good agreement in the cross-sectional EM field distribution of TEM cell with 2-dimensional analysis results. Based on this method, the first cutoff freque- ncy in high order modes in the cell and the electric field polarization are considered.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.1
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• pp.131-137
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• 2009

In this paper, we have manufactured hole type PRAM unit cell using phase change material $Ge_2Sb_2Te_5$. The phase change material $Ge_2Sb_2Te_5$ was deposited on hole of 500 nm size using sputtering method. Reset current of PRAM unit cell was confirmed by measuring R-V characteristic curve. Reset current of manufactured hole type PRAM unit cell is 15 mA, 100 ns. And electro and thermal characteristics of hole type PRAM unit cell were analyzed by 3-D finite element analysis. From simulation temperature of PRAM unit cell was $705^{\circ}C$.

• Membrane and Water Treatment
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• v.7 no.2
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• pp.115-126
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• 2016

In this study, computational fluid dynamics (CFD) analysis was conducted to investigate the flow pattern and to find the occurrence of dead zones in an existing capacitive deionization (CDI) cell. Newly designed cells-specifically designed to avoid dead zones-were analyzed by CFD in accordance with the flow rates of 15, 25 and 35 ml/min. Next, the separation performances between the existing and newly designed cell were compared by conducting CDI experiments in terms of salt removal efficiency at the same flow rates. Then, the computational and experimental results were compared to each other. The salt removal efficiencies of the hexagon flow channel 1 (HFC1) and hexagon flow channel 2 (HFC2) were increased 88-124% at 15 ml/min and 49-50% at 25 ml/min, respectively. There was no difference between the existing cell and the foursquare flow cell (FFC) at 35 ml/min.

• Journal of the Semiconductor & Display Technology
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• v.8 no.4
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• pp.37-42
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• 2009

The performance of an OLED(organic luminescent emitting device) fabrication system strongly depends on the design of the evaporation cell-source. Trends in display sizes have hauled the enlargement of mother glass substrates. The enlargement of substrates requires the improvement and the enlargement of the effusion cell-source for OLED evaporation process. The deposited layers should be as uniform as possible, and therefore it is important to know the effusion profile of the molecules emitted from the cell-source. Conventional 2D DSMC algorithm cannot be used for simulating the new concept cell-source design, such as a linear source. This work concerns the development of 3D DSMC (direct simulation Monte Carlo) analysis for simulating the behavior of the evaporation cell-sources. In this paper, the 3D DSMC algorithm was developed and the film thickness profiles were obtained by the numerical analysis.

• Journal of the Korean Ceramic Society
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• v.45 no.12
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• pp.788-795
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• 2008

An electrolyte supported SOFC cell was tested at $800^{\circ}C$ in air for 3600 h with an applied current density of $200\;mA/cm^2$ to examine possible cathode degradation issues. A scandium- stabilized zirconia (ScSZ) with additional manganese doping (ScSZ: Mn) was used as electrolyte. A strontium and copper-doped lanthanum ferrite (LaSrCuFe) and platinum were used as cathode and quasi-anode material, respectively. The DC resistance was logged over the complete testing period. Additionally, impedance spectroscopy was used from time to time to track changes of the cell in-situ. Post-test analysis of the cell using methods like scanning electron microscopy imaging and other electrochemical testing methods allow the identification of different degradation sources. The results indicate a promising combination of electrolyte and cathode material in terms of chemical compatibility and electrical performance.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.9
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• pp.752-760
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• 1991

The computer aided analysis is performed to investigate the influence of physical parameters (thickness and doping concentration, etc.) in the window, emitter, base on the efficiency characteristics of a uniformly doped hetroface cell. A field aided heteroface cell is newly designed on a basis of optimum data obtained from the theoretical analysis. The field aided heteroface cell fabricated using MOCVD exhibits a total/active area conversion efficiency of EFF. (tot) = 18.9% /EFF. (act.) = 21.4% under the natural incident light of 56.2 mW/cm\ulcorner having a low series resistance of Rs = 0.94 \ulcornercm\ulcornerand a high spectral response of S.R. (ext) > 90% in a range of $7700{\AA}$ < $8500{\AA}$.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.9
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• pp.62-70
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• 2010

Fuel cell system which can solve the environmental problem is receiving attention. To use utility power necessary power conversion system from low voltage that is generated by fuel cell system. because fuel cell has special characteristic of low voltage high current. To improve PCS's efficiency the paralleling method is used. Available the method could reduce the switching loss. But the existing research could not be found optimal result and accompanying several effects. In this study analysis several effects causing the parallel method. The effects have been demonstrated through simulations and experiments.