• Korean Chemical Engineering Research
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• v.58 no.3
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• pp.498-498
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• 2020

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2753-2754
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• 2010

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.703-706
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• 2009

• Korean Membrane Journal
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• v.6 no.1
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• pp.24-29
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• 2004

Poly(vinyl alcohol)(PVA) and hyaluronic acid(HA) hydrogel membranes were prepared with varying HA contents from 10 to 50 wt% of PVA. The water contents of the resulting PVA-HA hydrogel membranes in various pH conditions were measured. And the permeation coefficient of indomethacin was determined using several PVA-HA hydrogel membranes at various pH conditions and also 37$^{\circ}C$.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.11a
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• pp.76-79
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• 2003

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.767-770
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• 2017

Quadruple tank liquid level systems are popular in testing multivariable control systems for multivariable processes with positive or negative zeros. The liquid level system is nonlinear and it will help to illustrate the robustness of control systems. However, due to nonlinearity, it can be cumbersome to obtain process parameters for testing linear control systems. Perturbation sizes are limited for valid linearized process models, requiring level sensors with high precision. A simple method where the outlet orifice is replaced to a long tube is proposed here. The effluent flow rate becomes proportional to the liquid level due to the friction loss of long tube and the liquid level system shows near linear dynamics. It is applied to the quadruple tank system for easier experiments.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2280-2282
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• 2009

Amorphous zinc phosphate nanospheres were prepared via a sonochemical route. Zinc phosphate nanospheres were uniform in shape with an average diameter of 210 nm. The average diameter of nanospheres could be controlled by changing the pH of a precursor solution. This sonochemical method is simple, facile, economical, and environmentally benign. Non-crystalline characteristics of as-prepared zinc phosphate nanospheres were confirmed by X-ray diffraction, transmission electron microscopy, and FT-IR spectroscopy analyses. We believe this technique will be readily adopted in realizing other forms of zinc phosphate nanostructures.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.08a
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• pp.383-383
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• 2009

• Journal of the Korean Chemical Society
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• v.18 no.6
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• pp.453-455
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• 1974

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2435-2438
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• 2012