• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.371-378
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• 2016

In this study, a small portable sorting pilot for separation that can be used in dismantling construction site, which is the stage of construction waste generation, was developed, and its separation efficiency was evaluated to increase the actual recycling rate of the construction waste. The pilot was developed as portable sorting pilot for separation of 6 ton capacity that can handle one arm roll box within a $15m^2$ area in consideration of narrow places in the downtown area where a number of dismantling sites are located and various processes performed in the dismantling sites. In order to evaluate the efficiency performance of the developed device, the separation and sorting were carried out ten times with respect to trommel rotational speed RPM 2-3, 4-6 and 7-8. According to the results, the highest efficiency of about 90% was shown at RPM 6-7.

• Clean Technology
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• v.12 no.1
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• pp.37-44
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• 2006

The effectiveness of inorganic oxides (DT-30), anionic exchange resin (DT-60) and carbon absorbent (DT-80, DT-90) on the equilibrium and continuous separation characteristics and removal of cobalt, cesium and iodide ion in the waste water was investigated. As a result, DT-30, DT-80 or DT-90, and DT-60 showed excellent separation properties on the cesium, cobalt and iodide respectively. In the equilibrium experiment, the adsorption amount of cesium for DT-30 increased with temperature, but increasd largely with pH. In case of DT-80, adsorption of cobalt was depended on pH but was not influenced by temperature. In the continuous system by passing a heavy metal ion solution through the ion exchange tower, DT-30, DT-90 and DT-60 showed good separation characteristic for cesium, cobalt and iodide respectively. In this case, separation characterization of DT-30 on the cesium and of DT-60 on the iodide were better than that of DT-90 on the cobalt. From the experiment on the effect of impurities on the ion exchange characteristics, impurities such as surfactant and oil did not influence the efficiency of DT-90. In the mean while, ion separation capacity of DT-30 were decreased largely by impurities such as surfactant and oil. Also, surfactant had a strong influence on the effectiveness of DT-60. Accordingly, it turned out to be very important thing that impurities should be removed in the preprocessing stage.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.1267-1268
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• 2004

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.76.1-76
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• 2002

This paper addresses a method for nonlinear controller construction for a general nonlinear system with the separation of controller construction and manipulated values generation. The nonlinear system model is firstly expressed with the coefficients of state-depended representation. The nonlinear control is designed without any approximation based on the model with state-depended representation. At the stage of controller implementation for the nonlinear system, the manipulated values are calculated accurately by use of an algorithm of the numerical analysis. The numerical error for calculating the manipulated value can be reduced to zero by selecting the sampling interval being a small val...

• Korean Architects
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• s.484
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• pp.14-21
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• 2009

Creation village is to house diverse programs to complete the master plan which was established 13 years ago. The project was asked to envision the second stage leap of the college and also house programs related to the specialized creative activities with dormitory. The site is located right next to the main gate, so the project has very strong and symbolic image by its location. Therefore, the project is to carry out the college philosophy in education and also work with ideas of connection and separation with required diverse programs.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.11
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• pp.157-160
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• 1992

표면에 여러 가지 기능성기를 가지는 microspheres는 immunoassay, drug delivery system, cell separation등 의용공학분야에 응용이 기대되고 있다. 이들 분야의 응용을 위하여 유화제를 사용하지 않으면서, 기존의 회분식, 반회분식, seed 중합법등의 문제점을 극복한 two stage shot growth technique올 개발하여 여러 가지 기능성기가 표면에 도입된 microspheres를 제조하였으며, 응용의 전단계로서 이들 microspheres에 대한 모델 단백질(BSA)의 흡착실험을 pH, 기능 성기의 종류와 양, BSA농도를 변수로 행하여 최대 흡착량을 보이는 조건을 결정하였다.

• Membrane Journal
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• v.9 no.2
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• pp.89-96
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• 1999

국내 K-그룹 연구소에서 제조한 폴리설폰 중공사막의 산소/질소 혼합물에 대한 압력, stage , cut , 공급기체 혼합물의 조성에 따른 분리성능을 조사하였다. 본 실험의 압력범위와 온도 3$0^{\circ}C$에서의 이상분리인자 (O2/N2)는 5.7이었으며, 유입기체 혼합물의 21mole % 산소농도가 약 50 mole%로 농축되었다. 저압측과 고압측의 압력비는 산소농축에 미치는 영향이 적었으며 이상분리인자의 영향은 매우 컸다. 그러나, 이상분리인자가 증가함에 따라 이상분리인자의 영향은 둔화되었다. 따라서, 이상분리인자가 큰 신소재 개발과 더불어 공정변수의 최적화가 필요하다. 수학적 모델링에 의한 예측치와 실험치가 잘 맞았다.

• Macromolecular Research
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• v.9 no.1
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• pp.51-65
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• 2001

Two-stage emulsion polymerizations of hydrophobic monomers on hydrophilic seed polymer particles were carried out to make core-shell composite particles. It was found that the loci of polymerization in the second stage were the surface layer of the hydrophilic seed latex particles, and that it has resulted in the formation of either eccentric core-shell particles with the core exposed to the aqueous phase or aggregated nonspherical composite particles with the shell attached on the seed surface as many small separated particles. The driving force of these phenomena is related to the gain in free energy of the system in going from the hydrophobic polymer-water interface to hydrophilic polymer-water interface. Thermodynamic analysis of the present polymerization system, which was based on spreading coefficients, supported the likely occurrence of such nonspherical particles due to the combined effects of interfacial free energies and phase separation between the two polymer phases. A hypothetical pathway was proposed to prepare hydrophilic core-hydrophobic shell composite latex particles, which is based on the concept of opposing driving and resistance forces for the phase migration. It was found that the viscosity of the monomer-swollen polymer phase played important role in the formation of particle morphology.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.3
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• pp.371-380
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• 1998

The flow patterns and dynamic properties of ship's propulsion mechanism of two-stage Weis-Fogh type are studied by the discrete vortex method. In order to study the effects of the interaction of the two wings two cases of the phase differences of the wing's motion are considered the same phase and the reverse phase. The flow patterns by simulations correspond to the photographs obtained by flow visualization and flowfield of the propulsion mechanism which is unsteady and complex is clearly visualized by numerical simulations. The time histories of the thrust an the drag coefficients on the wings are also calculated and the effects of the interaction of the two wings are numerically clarified.

• Journal of Biomedical Engineering Research
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• v.14 no.3
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• pp.209-220
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• 1993

Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, Immunomagnetic cell separation. To synthesize micro-spheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio or synthesized microspheres was always smatter than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6-13 times higher than thats of the ml crospheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin Is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption Isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin ) . The effect of the kind and the amount of surface functional group was also examined.p was also examined.