• Transactions of Materials Processing
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• v.4 no.4
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• pp.295-301
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• 1995

• Cement Symposium
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• no.10
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• pp.15-29
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• 1982

• Cement
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• s.188
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• pp.10-19
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• 2010

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.405-410
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• 2010

The photovoltaic performance of DSSCs fabricated with different electrode thickness and different annealing temperature with the P25 $TiO_2$ and the Dyesol $TiO_2$ was measured. Thickness change of $TiO_2$ electrodes was measured using cross-sectional FE-SEM before and after annealing. Photovoltaic efficiencies of DSSCs were also measured by changing annealing temperature of platinum (Pt) paste on the counter electrode. Photovoltaic performances of DSSCs made with one layer of P25 (${\sim}20.4\;{\mu}m$) and one layer of Dyesol $TiO_2$ (${\sim}9.1\;{\mu}m$) annealed at $500^{\circ}C$ for 30 min. showed highest efficiencies of 3.8% and 5.8%, respectively.

• Journal of Digital Convergence
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• v.16 no.5
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• pp.463-468
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• 2018

The purpose of the study was to investigate the gender differences of anaerobic capabilities between anaerobic capacity(AC) from Wingate test and anaerobic work capacity(AWC) from critical power test in untrained male and female adults. Both tests were carried out to 12 male and 13 female subjects on a Monark cycle ergometer. The results of this study demonstrated that men were higher than women in AC for the Wingate test, but no gender difference(J/kg) in AWC for the Critical Power test. There was a significant relationship between AC(J/kg) and AWC(J/kg) in women(r=0.61, p<0.05), but no significant relationship in men(r=-0.32, p>0.05). ANCOVA analyses using $VO_{2max}$ and body weight as covariates had significant influence on the AWC gender difference. The study provides preliminary data on gender differences of anaerobic capabilities.

• Resources Recycling
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• v.19 no.3
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• pp.16-23
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• 2010

Coal briquette use has dramatically increased because of high oil prices. Hence, it is necessary to develop an environment-friendly recycling technique of the coal briquette ash. The coal briquette ash contains a large amount of an unburned carbon content and a mullite with high thermal property, so it is considered to be used as raw materials of sintered eco-brick. This study aimed to investigate on how the unburned carbon affects properties of the sintered eco-brick. The eco-brick was mixed with the ratio of 50 wt% coal briquette ash having the unburned carbon 10.5 wt% and 50 wt% cullet, then being sintered at $950^{\circ}C$, which of the compressive strength was in line with the first class of the sintered clay brick standard(KS L 4201). In particular, the compressive strength of the sintered eco-brick was equal to the first class of the KS L 4201 despite the increase of mixing ratio for coal briquette ash with 1.0 wt% unburned carbon to 70 wt%.

• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.655-664
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• 2007

The inherent characteristic of concrete tensile cracks, directional nonlocal crack damage, causes so-called rotating tensile crack damage and softening of compressive strength. In the present study, a plasticity model was developed to describe the behavior of reinforced concrete planar members In tension-compression. To describe the effect of directional nonlocal crack damage, the concept of microplane model was combined with the plasticity model. Unlike existing models, in the proposed model, softening of compressive strength as well as the tensile crack damage were defined by the directional nonlocal crack damage. Once a tensile cracking occurs, the microplanes of concrete are affected by the nonlocal crack damage. In the microplanes, microscopic tension and compression failure surfaces are calculated. By integrating the microscopic failure surfaces, the macroscopic failure surface is calculated. The proposed model was implemented to finite element analysis, and it was verified by comparisons with the results of existing shear panel tests.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3971-3976
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• 2009

In this study, we secured wasted oyster shells as raw materials in order to applicate it to corrosion preventive ceramic coating reagent in the drinking water pipeline. Then, we investigated physicochemical properties in terms of basic calcination processing. Oyster shell was composed with 92.08% of $CaCO_3$ and the shapes of the pulverized particles were mostly oval. The calcined oyster shell showed increasing tendency of weight loss and of calcium content with the lapse of time and increase of temperature. The result indicates that the higher calcination processing temperature and the uniformly smaller particle size give more efficiency during calcination process. Therefore it is anticipated to be a good ceramic material to protect a surface of cleaning bed and inside of a tap water pipes from corrosion.

• Journal of KIISE:Computing Practices and Letters
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• v.12 no.3
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• pp.208-217
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• 2006

This paper presents a cloth simulation technique that implements plastic deformation. Plasticity is the property that material does not restore completely to the original state once deformed, in contrast to elasticity. We model cloth using a particle model, and posit two kinds of connections between particles, i.e. the sequential connections between immediate neighbors, and the interlaced connections between every other neighbors. The sequential connections represent the compression and tension of cloth, and the interlaced connections the bending in cloth. The sequential connections are modeled by elastic springs, and the interlaced connections by elastic or plastic spring depending on the amount of the current deformation of the connections. Our model is obtained by adding plastic springs to the existing elastic particle model of cloth. Using the new model, we have been able to simulate bending wrinkles, permanently deformed wrinkles, and small wrinkles widely distributed over cloth. When constructing elastic and plastic spring models for sequential and interlaced connections, we took pain to prevent the stiffness matrix of the whole cloth system from being indefinite, in order to help achieve physical stability of the cloth motion equation and to improve the effectiveness of the numerical method.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.30-37
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• 2005

This study aimed at offering basic data to develop a new use of sawdust and rice husk. Research investigated the variation of density, weight loss and dimensional decreasing rate by the percentage of resin impregnation and carbonization temperature of ceramics, which were formed by the percentage of resin impregnation of 40~80% and carbonization of $600{\sim}1200^{\circ}C$ with board impregnated with phenolic resin made from sawdust and rice husk. The results of this study were as follows:1) As the percentage of resin impregnation increased, the thickness shrinkage and weight loss were decreased; on the other hand, density and modulus of rupture increased. Meanwhile, the carbonization temperature at $1200^{\circ}C$ showed the highest values, as the density was $0.81g/cm^3$ and the bending strength was $77.9kgf/cm^2$ in the percentage of resin impregnation at 70%. 2) As the carbonization temperature grew higher the linear shrinkage, thickness shrinkage and weight loss increased while the density increased until the carbonization temperature of $1000^{\circ}C$; but then decreased slightly at $1200^{\circ}C$.