• International Journal of Highway Engineering
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• v.7 no.1 s.23
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• pp.21-29
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• 2005

One way to recycle the construction wastes is to use the waste concrete aggregates as the pavement materials. Although there are many studies and technical developments about waste concrete aggregates, the impurities produced in the process of the aggregate production prevent the use of the waste concrete aggregates in the pavement construction. In this study, the impurities included in the recycled waste aggregates were classified into inorganic and organic ones according to their characteristics, and the influences of each impurities on the pavement performance were presented. It was also showed that the limit of impurity content in the lean concrete base through the correlation between the inorganic impurity content and the compressive strength, and that in the granuler subbase layer through the correlation between the organic impurity content and the modified CBR. In conclusion, it is possible to apply waste concrete aggregates for the pavement when inorganic impurity content is less than 10% in the lean concrete base, and organic impurity content is less than 2% in granular subbase.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.10
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• pp.57-60
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• 1971

In this experiment 5 Korean varieties and 3 U.S.A. varieties of wheat were investigated for their moisture content, ash content, crude protein content and extraction rate. The results are summarized as follows; 1. In the case of U.S.A. wheat, the ash content is directly proportional to the content of protein but the extraction rate is negatively correlated to the content of ash. 2. In the case of korean wheat, there is no proportional tendency as in the U.S.A. wheat. It might be cause by the low extraction rate where the endosperm is hardly separated from the bran layer at the same conditions of temering process. 3. The concentration of protein particles in the endospern, is centrifugal in the U.S.A. wheats, but in the Korean varieties the direction is oppositional to the U.S.A. varieties. 4. Yooksung ＃3, Cahngkwang, Youngkwang and Hard winter wheat are adapted to the production of all purpose flour or noodle flour; Noring ＃4, Jinkwang and Softwhite wheat are suitable for the process of cake flour; and Dark northern spring is just adaped to the production of bread flour.

• Journal of the Korean Geotechnical Society
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• v.22 no.7
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• pp.37-44
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• 2006

This paper investigates strength characteristics and stress-strain behaviors of geogrid mixing reinforced lightweight soil. The lightweight soil was reinforced with geogrid in order to increase its compressive strength. Test specimens were fabricated by various mixing conditions including cement content, initial water content, air content and geogrid layer and then unconfined compression tests were carried out. From the experimental results, it was found that unconfined compressive strength as well as stress-strain behavior of lightweight soil was strongly influenced by mixing conditions. The more cement content that is added to the mixture, the greater its unconfined compressive strength. However, the more initial water content or the more air foam content, the less its unconfined compressive strength. It was observed that the compressive strength of reinforced lightweight soil increased reinforcing effect by the geogrid for most cases. Stress-strain relation of geogrid mixing reinforced lightweight soil showed a ductile behavior rather than a brittle behavior. In reinforced lightweight soil, secant modulus ($E_{50}$) also increased as its compressive strength increased due to the inclusion of geogrid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1245-1250
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• 2006

This study was carried out to develop the method of preparing lecithin-fortified ginseng extract. Firstly, soybean lecithin was mixed with soybean oil (LCS) in varying ratio (2.5%, 5%, 10% and 20%). Then, one part volume of LCS was mixed with three parts volume of ginseng extract with 10% solid matter content and the mixture was vortexed vigorously. Finally, the mixture was spinned at the speed of 3,000 rpm for 30 minutes to separate oil and aqueous ginseng extract layer (AG). AG was then subjected to qualitative and quantitative analysis of phospholipids and ginsenosides. Fatty acid composition and crude fat content before and after LCS was determined. Stability of lecithin in ginseng extract was determined by analyzing phospholipid content in the one third upper and lower layer of the concentrated AG in Falcon tubes while storing the LCS treated concentrated AG in 4, 25 and 40oC for 6 months. Ratio of lecithin transferred to AG increased with the increase in lecithin content of soybean oil. There was no significant change in fatty acid composition and crude fat content, and ginsenoside content in the ginseng extract before and after LCS treatment. TLC and HPLC pattern of saponin fraction before and after treating the ginseng extract with LCS demonstrated no observable difference. There was no change in lecithin content in the upper and lower one third layer of ginseng extract in the tubes after storing the concentrated AG in 4, 25 and $40^{\circ}C$ for 6 months. Ginsenosides HPLC pattern was not changed when stored the LCS-treated ginseng extract in those conditions for six months, indicating satisfiable stability of the LCS-treated concentrated ginseng extract. From these results, it can be concluded that treatment of the ginseng extract with lecithin containing soybean oil is a labor effective method with satisfiable stability to fortify lecithins to ginseng extract.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.83.1-83.1
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• 2010

Hydrogenated a-SiGe middle cell for triple junction solar cell was investigated with various process parameters. a-SiGe I-layer was deposited at substrate temperature $245^{\circ}C$ and hydrogen content(R) was up to 26.7. Low optical bandgap(1.45eV) of a-SiGe cell was applied for middle cell although a-SiGe single cell efficiency with low Ge content was higher. And this cell was applied to the middle cell of a glass superstrate type a-Si/a-SiGe/uc-Si triple junction solar cell. The triple junction solar cell was resulted in the initial efficiency of about 9%, area $0.25cm^2$, under global AM 1.5 illumination.

• BMB Reports
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• v.28 no.4
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• pp.323-330
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• 1995

Recent studies have shown that dopamine applied to cultured swimming motor neurons of Polyorchis penicillatus produces an inhibitory action by opening potassium channels through $D_2$-like receptors. In this study, it was demonstrated that dopamine found in the hydromedusa was not from exogenous sources and the content of dopamine depended on the $Ca^{2+}$ content of the dissecting media. In addition, a combination of thin layer chromatography and high performance liquid chromatography showed the presence of DOPA and DO PAC-like compounds in the jellyfish. The glyoxylic acid method for catecholamines suggested that a population of small cells, neither swimming motor neurons nor B-like neurons, had dopaminergic systems. From all these results, it is suggested here that DA synthesized from DOPA in some cells is released. being dependent on calcium concentrations, into a synaptic cleft and degraded into DOPAC after acting as an inhibitory transmitter to swimming motor neurons.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2006.11a
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• pp.64-65
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• 2006

The effects of garlic extracts, lactic acid bacteria, copper and selenium as cholesterol lowering material on productivity and content of egg cholesterol in layer were investigated. The layers were divided into seven treatment groups and fed commercial diet or experimental diets containing probiotics, garlic powder, selenium and copper for 6 weeks. There was no significant difference in egg production between groups. The content of egg yolk cholesterol by combination feeding of probiotics, garlic powder, selenium and copper were significantly reduced by 13.5-29.8% as compared to that of control. The levels of mRNA expression of HMG-CoA reductase were significantly decreased by dietary treatments.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.153-156
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• 2008

The use of high Xe content gas is a powerful method for improving the discharge efficacy in PDP, but the accompanying high driving voltage prevents it from being used aggressively. In this paper, we tried to find a method to lower the driving voltage under high Xe gas condition with a new protecting layer. The effective secondary electron emission caused by Xe ions can result in the low voltage driving in panels with high Xe content gas and more importantly high luminous efficacy which were confirmed with the computer simulation and panel experiment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.56-58
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• 1989

All-polycrystalline Cd$_1$-xZnxS/CdTe solar cells have been fabricated by coating CdTe slurries with 4.5 wt% of CdCl$_2$on the sintered Cd$_1$-xZnxS films and by sintering CdTe layer at 6$25^{\circ}C$ for lh in nitrogen atmosphere. Solar efficiency of the sintered Cd$_1$-xZnxS/CdTe solar cells increases as the Zn content increases up to x=0.06 and then decreases with further increase in the Zn content. A solar efficiency of 12.5% under a solar intensity of 76mW/$\textrm{cm}^2$ was observed in a Cd 0.94 Zn0.06S/CdTe solar cell. By optimizing the amount of CdCl$_2$in the slurry and sintering conditions, it is possible to produce Cd$_1$-xZnxS/CdTe solar cells with efficiency higher than 12%.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.230-230
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• 2009

In this work, Porous Carbons (PCs) were prepared by using a chemical acid treatment, and the hydrogen storage behaviors of PCs doped by Pt nanoparticles were investigated. The hydrogen storage capacities of the Pt-doped carbons with a platinum content of 0.2 - 1.5 wt.% were evaluated by a volumetric adsorption method at 298K and 10 MPa. The microstructures of samples were examined by XRD and SEM. It was found that the hydrogen storage capacitiesof the PCs dramatically increased, but the amount of hydrogen stored from the samples began to decrease after 0.6 wt.% of Pt content due to the pore blocking. These results indicate that a suitable amount of supported catalysts and layer intervals of carbons had a very important impact on hydrogen storage behaviors.