• Membrane and Water Treatment
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• v.11 no.2
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• pp.111-121
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• 2020

The fouling of Nanofiltration membrane (NF) was examined using wastewater containing reactive black dye RB5 of 1500 Pt/Co color concentrations with 16890 mg/l TDS collected from El-alamia Company for Dying and Weaving in Egypt. The NF-unit was operated at constant pressure of 10 bars, temperature of 25℃, and flowrate of 420 L/min. SEM, EDX, and FTIR were used for fouling characterization. Using the ROIFA-4 program, the total inorganic fouling load was 1.07 mM/kg present as 49.3% Carbonates, 10.1% Sulfates, 37.2% Silicates, 37.2% Phosphates, and 0.93% Iron oxides. The permeate flux, recovery, salt rejection and mass transfer coefficients of the dye molecules were reduced significantly after fouling. The results clearly demonstrate that the fouling had detrimental effect on membrane performance in dye removal, as indicated by a sharp decrease in permeate flux and dye recovery 68%. The dye mass transfer coefficient was dropped dramatically by 34%, and the salt permeability increased by 14%. In this study, all the properties of the membrane used and the fouling that caused its poor condition are identified. Another study was conducted to regeneration fouled membrane again by chemical methods in another article (Abdel-Fatah et al. 2017).

• Journal of Energy Engineering
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• v.26 no.4
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• pp.57-66
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• 2017

Since the heat is not as fast as the electric power and the loss is relatively large compared to the electric power, it is not realistic to operate the thermal transfer system with on operation center like electric power trading. In the case of the Korea District Heating Corporation, where all the thermal transfer are currently being made, only two or four adjacent heat-generating power plants are being the heat trading. Therefore, In this paper, we concluded that it is appropriate to divide the integrated operation center for heat trading into several regions, to operate the hub integrated operation power plant in each region to reflect the characteristics of the heat medium and proposed the thermal transfer mechanism among integrated energy operators. Then, we have developed an algorithm that can optimize the heat transaction for the proposed mechanism and applied it to the actual operators to verify the usefulness of the proposed algorithm.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.8
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• pp.408-418
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• 2017

Supercritical carbon dioxide ($sCO_2$) power system is emerging technology because of its high cycle efficiency and compactness. Meanwhile, PCHE (Printed Circuit Heat Exchanger) is gaining attention in $sCO_2$ power system technology because PCHE with high pressure-resistance and larger heat transfer surface per unit volume is fundamentally needed. Thermo-fluidic characteristics of $sCO_2$ in the micro channel of PCHE should be investigated. In this study, heat transfer characteristics of $sCO_2$ of various inlet conditions and cross-sectional shapes of single micro channel were investigated experimentally. Experiment was conducted at supercritical state of higher than critical temperature and pressure. Test sections were made of copper and hydraulic diameter was 1 mm. Convective heat transfer coefficients were measured according to each interval of the channel and pressure drop was also measured. Convective heat transfer coefficients from experimental data were compared with existing correlation. In this study, using measured data, a new empirical correlation to predict near critical region heat transfer coefficient is developed and suggested. Test results of single channel will be used for design of PCHE.

• Journal of Radiation Protection and Research
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• v.16 no.2
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• pp.55-65
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• 1991

Soil-to-plant transfer coefficients of Mn-54, Co-60, Zn-65, and Cs-137 were estimated for the edible parts of the rice, soybean, lettuce, carrot, and squash grown in different soils by radiotracer uptake experiments using pot cultures. The transfer coefficients of radionuclides were in the order of Zn-65 > Mn-54 > Cs-137 > Co-60 in most of the cases studied. The coefficients for soybean were roughly an order of magnitude higher than those for rice. Among vegetables, lettuce mostly showed the highest value and squash, the lowest. In the strongly acidic soils, transfer coefficients were much higher than in the moderately acidic soils. From the data obtained. crop-specific transfer coefficients of the four nuclides were proposed for the use in Korean food-chain radiation dose assessment.

• Plant Biotechnology Reports
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• v.3 no.3
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• pp.213-223
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• 2009

Lipid transfer proteins (LTPs) are widely distributed in the plant kingdom, but their functions remain elusive. The proteins AlLTP2-4 were isolated from three related Allium plants: garlic (A. sativum L.), Welsh onion (A. fistulosum L.), and Nanking shallot (A. ascalonicum L.). These novel proteins comprise a new class of LTPs associated with the Ace-AMP1 from onion (A. cepa L.). The AlLTP genes encode proteins harboring 132 common amino acids and also share a high level of sequence identity. Protein characteristics and phylogenetic analysis suggest that LTPs could be classified into five distinct groups. The AlLTPs were clustered into the most distantly related plant LTP subfamily and appeared to be restricted to the Allium species. In particular, the number of amino acids existing between the fourth and fifth Cys residue was suggested as a conserved motif facilitating the categorization of all the LTP-related proteins in the family. Unlike other LTPs, AlLTPs harboring both the putative C-terminal propeptide and N-terminal signal peptide were predicted to be localized to cytoplasmic vacuoles. When a chimeric GFP protein fused with both N-terminal and C-terminal AlLTP2 signal peptides was expressed in rice cells, the fluorescence signal was detected in the endomembrane compartments, thereby confirming that AlLTPs are an unprecedented intracellular type of LTP. Collectively, our present data demonstrate that AlLTPs are a novel type of LTP associated with the Allium species.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5D
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• pp.627-634
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• 2009

The BTL (Build-Transfer-Lease) contract of construction project serves as a part for early establishment of industrial foundation for social overhead capital. However, project cost of BTL contract is focused on initial construction cost. Accordingly, operation cost is lowly evaluated because there is no standard criterion for estimating maintenance cost for the facility. The low operation cost can be a factor that reduces service quality of facility operation. This study suggests a resonable method for estimating cost and manpower in the operation phase by using the existing practical data for wastewater treatment plant by BTL contract. The results of the study can be used for evaluating rough operation cost and manpower of similar plant project by facility size.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.12
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• pp.1281-1287
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• 1990

A new thermal power plant feed-water system model, which is based on Astrom, is presented. Astrom's model has some difficulties in applying to practical systems because it is not able to measure the heat and energy transfer loss. Hence, in order to make up for these difficulties, the Gas State Equation is added to the model. Computer simulations are performed to show the validity of the new model at thermal power plant with practical boiler operating data and to verify the L.Q. controller effect on boiler drum level system.

• Journal of Plant Biology
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• v.32 no.4
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• pp.227-233
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• 1989

Single cells obtained from suspension culture of mature embryo-derived callus in wheat(Triticum aestivum L. cv Jang Kwang) were cultured to regenrated into the plantlet. Cell clusters and embryogenic calluses were efficiently developed from when the single cells clutured on the MS medium supplemented with 10${\mu}{\textrm}{m}$ 2,4-D. Upon transfer to hormone-free MS medium containing 10 mg/I AgNO3, embryogenic calluses gave rise to shoots, probably through somatic embryogenesis.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2093-2098
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• 2005

In this paper, $H_{2}$ designs for the one-degree-of-freedom decoupling control systems are treated for the generalized plant. The optimal $H_{2}$ controller is obtained together with the ones that yield finite $H_{2}$ cost functions under compact assumptions. It is shown that the optimal closed transfer matrix is strictly proper under the reasonable order assumptions on the generalized plant.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.64.6-64
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• 2002

This paper presents a procedure of implementing a robust controller for a paper-making plant in DCSs. A paper-making process generally has triple problems to automatically tune its output qualities : Long transport delays which are not able to be simply linearized. The transfer matrix of the process is not square. And every plant model has some uncertainty in low and middle frequency region. To tackle these problems, a multi-input / multi-output (MIMO) plant model having some uncertainty was derived by considering some physical and mechanical principles of the process. Then a MIMO robust \ulcornercontroller is designed and implemented in a real DCS as function block type. Som...