• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.3
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• pp.616-621
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• 2005

In this paper. digital watermarking algorithm based on human visual system and transform domain is presented. Firstly, original image is separated into RGB thannels, watermark is embedded into the coefficients of DCT so as to consider a contrast sensitivity and texture degrees. In preprocessing, DCT domain based transform is involved and binary image of visually recognizable patterns is utilized as a watermark. Consequently, experimental results showed that proposed algorithm is robust and imperceptibility such destruction attack as JPEG compression.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.12
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• pp.1249-1265
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• 1991

In this paper, a fast and adaptive feature extraction algorithm for textured image segmentation is proposed. First, a conventional algorithm to extract the statistical texture features are described and we obtain the recursive equations from that conventional method and it is used for extraction of sevaral texture features. And also we propose the adaptive algorithm which extract the texture features. To evaluate the performance of proposed algorithm, we apply the proposed method to artificial texture images. From the results of computer simulation, the proposed method is superior to the conventional one.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.423-423
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• 2012

Recently, many researchers made progress in various studies improving the efficiency of dye-sensitized solar cell. In this paper, we used glass textured by wet-chemical etching process for improvement of photocurrent density in dye-sensitized solar cells. This is owing to increase coefficient of light utilization. Consequently, DSSC using the textured glass exhibit a Jsc of 9.49 mA/$cm^2$, a Voc of 0.73 V and a fill factor (FF) of 0.67 with an overall conversion efficiency of 4.64. This result showed increasing of 20% current density and 16% conversion efficiency using the textured glass. These results suggested that glass texturing was very effective in controlling the light-scattering properties into the photovoltaic cell.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.123-128
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• 1991

Addition of two different salt mixtures of sodium phosphates, Ca-EDTA, $NaNO_2$ and sodium citrate were investigated for their effects on relative viscosity, textrue, sensory properties of kimchi and solids contents of kimchi and kimchi liquid during fermentation at $4{\sim}3.5^{\circ}C$. The salt mixtures were added into half fermented kimchi with the concentration range of $0.001{\sim}0.01\;M$. The results showed that higher values in viscosity of kimchi liquids were obtained for those fermented at low temperature and with salts mixtures added. The hardness of Chinese cabbage was gernerally increased until pH 4.0 reached and then decreased thereafter for those fermented without salts mixture. However the salts added kimchi showed no decrease and a slightly harder texture measured at the late stage of fermentation. Soluble solids concentration steadly decreased in kimchi liquids for those salts mixture added while those without salts mixture were initially increased followed by slow decrease. Comparison of sensory properties showed that the degree of changes was reduced when salt mixture was added. Higher scores in fresh-sourness and acidic taste, hardness and chewiness in texture and lower moldy odor were obtained when the data was compared for those kimchi having the pH range of $4.0{\sim}4.2$.