• Korean Journal of Food Science and Technology
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• v.15 no.2
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• pp.133-134
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• 1983

Some metallic ions such as copper, manganese, iron, zinc and cadmium in ginseng extract, originated from white ginseng, were determined by atomic absorption spectrophotometry. The extracts were prepared with water, 35% ethanol, 50% ethanol or 75% ethanol solution followed by filtration or centrifugation. Greater amounts of metallic ions were found in the solution filtrated by filter paper (Toyo No. 5A) or by filter cloth than in that of centrifugation. The residual amount of metallic ions in the extract decreased with increasing concentration of ethanol. The percentages of each metallic ion in ginseng extracts on the basis of original amount of metallic ions were as follows: Cu, 10.4-31.9%, Fe,5.1-19.0%, Mn,3.0-12.2% Zn,7.4-12.0%, Cd,5.9-11.8%.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.3
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• pp.61-66
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• 2008

For the production of urethane prepolymer, the effect of process parameters such as diisocyanate MDI and polyol TDI was tested. In this paper, design of experiments has been adopted for studying the effect of the process parameters on the improvement of NCO and viscosity of pre-polymer. As a result of comparison of different parameters, the effect of polyol was stronger than that of isocyanate in comparison of reactivity according to the amounts of isocyanate and polyol. Especially, NCO and viscosity of pre-polymer affected a product safety.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.11a
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• pp.78-81
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• 2010

In this paper, we propose an efficient and effective selective protection scheme to SVC that exploit the propagation of protection effect by protecting significant frames that can give the maximum visual quality degradation. We model SVC dependency coding structure as a directed acyclic graph which is characterized with an estimated visual quality value as the attribute at each node. The estimated visual quality is calculated by using our model based on the proportions of intra- and inter-predicted MBs, amounts of residual, and estimated visual quality of reference frames. The proposed selective protection scheme traverses the graph to find optimal protection paths that can give maximum visual quality degradation. Experimental results show that the proposed selective protection scheme reduces the required number of frames to be protected by 46.02% compared to the whole protection scheme and 27.56% compared to the layered protection scheme.

• Journal of Power System Engineering
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• v.11 no.2
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• pp.64-71
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• 2007

The main purpose of this study is to analyze the characteristics of toluene removal by plasma, photocatalyst, and plasma/photocatalyst system with the major parameters such as flow rate, inlet toluene concentration and applied voltage, etc., experimentally. In the combined plasma/photocatalyst process, rates of toluene conversion are represented as 99% at flow rate 250, 500 mL/min while, below 97% at flow rate 1000 mL/min due to the low residence time(reaction time) at the same applied voltage 4173 voltage and toluene inlet concentration 50 ppm. The intermediate products are detected by GC/MS analysis showing the small amounts of benzoic acid, benzyl alcohol and residual ozone concentration $0.04{\sim}0.05$ ppm generated by plasma process in the present system.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.1 s.41
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• pp.65-71
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• 1992

The influences of hydrophilic treatment of the PET fabric on soiling and detergency of triolein were studied. The amounts of residual triolein were determined by radiotracer analysis, and distributions of the unsaturated oils on the fabric were evaluated by backscattered electron images. The removal of triolein was increased when the PET fabrics were treated. SRP pretreatment was more effective on the oily soil removal than the of addition of SRP in the detergent. The oily soil of triolein only was packed between the fibers, but mixed soil was distributed around the fibers. When the mixed soil was used, detergent solution could penetrate the continuous interfiber capillaries, this would be one of the reasons that mixed soil was removed rmore extensively.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.40.1-40.1
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• 2017

Massive early-type galaxies (ETG) have been spectroscopically confirmed up to z>3 which, together with their ages and abundances at z>1.5, implies that their progenitors must have converted gas into stars on short timescales. The termination of star formation in these galaxies can occur through several channels, but they remain largely conjectural, in part due to the current lack of direct measurements of the amount of residual gas in high redshift ETGs. Here I will present constraints on the star formation rate and dust/gas content of z=1.4-2.5 ETGs. These galaxies, close to their epoch of quenching, contained more than 2 orders of magnitude more dust than their local counterparts, which suggests the presence of substantial amounts of gas and a low star formation efficiency.

• Journal of Korea Foundry Society
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• v.15 no.6
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• pp.546-557
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• 1995

This study was undertaken to obtain an improved understanding of the effects of alloying elements on the residual amounts of Mg in the melt and on the resultant microstructure of compacted vermicular graphite cast irons, and the influence of alloying elements and cooling rates during solidification on the formation of phosphide eutectics, and on the mechanical properties of compacted vermicular graphite cast irons containing copper, tin, molybdenum for producing pearlitic matrix, and also containing phosphorus and boron for increasing wear resistance were evaluated.

• Korean journal of food and cookery science
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• v.12 no.1
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• pp.108-114
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• 1996

The study was carried out to compare the reaction rate of Maillard browning reaction of 2 dipeptides (Leucylglycine, Tryptophylglycine) and 4 amino acids (Lysine, Glycine, Leucine, Tryptophan) with xylose heated for 0∼24 hours at 60∼100$^{\circ}C$. 1. The color intensity of the browning mixture heated at 100$^{\circ}C$ for 24 hours was the highest in tryptophanxylose, and in order to tryptophylglycine-xylose > lysine-xylose > leucylglycine-ylose > leucine-xylose > glycine-xylose. 2. The reaction rate constants (k) determined from the browning pigment concentrate with time were similar to the result of the color intensity, that is, the k were the highest in the tryptophan-xylose. 3. The residual amounts of dipeptides, amino acids and xylose in the browning mixture diminished as the browning temperature increase. 4. The activation energies (Ea) calculated from k were the highest in leucine-xylose (143.72 J/mol) and the lowest in tryptophan-xylose (117.45 J/mol). The range of Q$\sub$10/ values were 2.84∼3.58.

• Journal of Welding and Joining
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• v.18 no.4
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• pp.38-47
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• 2000

Characteristics of the interface between tube and tube sheet which were formed by explosive expansion and roll expansion, have been studied in the research. The results are as follows: Optimum amounts of explosives for the expansion of Alloy 600 (19.05mm and 15.88mm) were found to be RDX 3.5-8.5g/m. Because explosive expansion caused les strain hardening and increased bounding strength, characteristics of the explosively expanded were better than those of mechanically expanded. As the transition region of the explosive expansion is inactive, the resistance to the stress corrosion cracking increases by 30∼40% compared to the roll and hydraulic expansion.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.8
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• pp.1062-1068
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• 2000

The effect of heat exchanger surface treatment on the frosting/defrosting behavior in a fin-tube heat exchanger is investigated experimentally. It is found that the hydrophilic surface mainly influences on the frosting behavior, however, the hydrophobic surface gives some influence on the defrosting behavior. In view of frosting performance, surface-treated heat exchanger with either hydrophilic or hydrophobic characteristic shows a little improvement in the thermal performance than the aluminium heat exchanger with no surface treatment. The result reveals that the heat exchanger with hydrophobic surface treatment is more effective in view of the defrosting efficiency and time. The amounts of residual water on the surface-treated heat exchangers are shown to be smaller than those of the bare heat exchanger, therefore further improvements on the performance of re-operations are expected.