• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.207-208
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• 2016

The most important things for the production of recycled aggregates are saving energy, suppressing the generation of by-product fine particles and sustaining the performance of concrete. As solutions, this study proposes this technology of improving the performance of recycled aggregates through forced carbonation.1) It is to stimulate and carbonate the bond paste part that causes the deterioration of recycled aggregates. Particularly, the purpose of this technology is to fill and chemically stabilize pores inside the bond paste, further improving the quality of recycled aggregates with a decreased absorption rate and an enhanced aggregate strength. Ultimately, it is possible to obtain a carbonation model, depending on the paste ratio and particle-size distribution of recycled aggregates. Moreover, by calculating the optimum carbonation period through the verification of this carbonation model, it is possible to examine how much the strength is improved by the reformation of recycled aggregated.

• Journal of the Korean institute of surface engineering
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• v.46 no.1
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• pp.22-28
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• 2013

$WS_2$ particles were added to micro-diamond blades with Cu/Sn binding metal as lubricants to improve cutting efficiency. It was found in previous works that the added $WS_2$ lubricant could reduce remarkably the momentary energy consumption during dicing tests but increased wear rate slightly owing to weak bonding between lubricant particles and bond metals. In the present work, the surface of $WS_2$ lubricant particles were etched for activating the surface of $WS_2$ particles that provide even distribution of particles during powder mixing process and improvement of wetting at the interfaces between $WS_2$ particles and molten Cu/Sn bond metals during pressurized sintering so that could provide the improved strength of micro-blades and result in extended life. Chipping behavior of workpiece with the types of micro-blades including $WS_2$ were compared because it is important in semiconductor and micro-packaging industries to control average roughness and straightness of sliced surface which is closely related with quality.

• International Journal of Reliability and Applications
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• v.5 no.4
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• pp.129-145
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• 2004

We use a novel, forced censoring technique that closer fits the lower tails of strenth distributions to better estimate extremly smaller percentiles for measuring progress in continuous improvement initiatives. These percentiles are of greater interest for companies, government oversight organizations, and consumers concerned with safely and preventing accidents for many products in general, but specifically for medium density fiberboard (MDF). The international industrial standard for MDF for measuring highest quality is internal bond (IB, also called tensile strengh) and its smaller percentiles are crucial, especially the first percentile and lower ones. We induce censoring at a value just above the median to weight lower observations more. Using this approach, we have better fits in the lower tails of the distribution, where these samller percentiles are impacted most. Finally, bootstrap estimates of the small percentiles are used to demonstrate improved intervals by our forced censoring approach and the fitted model. There was evidence from the study to suggest that MDF has potentially different failure modes for early failures. Overall, our approach is parsimonious and is suitable for real time manufacturing settings. The approach works for either strengths distributions or lifetime distributions.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.3
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• pp.18-23
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• 2001

The effect of pulp consistency on the deinking properties in the ozone deinking of ONP was investigated in order to develop the environmentally friendly deinking method. The pulp consistency and ozone treatment time were varied for this purpose. Higher pulp consistency during ozone treatment gave better ink removal efficiency than the conventional deinking method. In was also found that the increase of pulp consistency can decrease the ozone treatment time which can meet the deinking quality. WRV of ozone deinked pulp obtained at 10% and 30% of pulp consistencies was lower than those of the conventional deinking method. However, the higher pulp consistency during ozone treatment improved WRV. Highest brightness was obtained at the ozone treatment condition of 30% pulp consistency and 10 minutes. The lower brightness at the other ozone treatment condition should be originated from the excessive decrease of ink particle size and then decrease of true ink removal efficiency. Scott bond was increased with the increase of pulp consistency and treatment time. However, the improvement of breaking length with ozone treatment was no significant.

• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1126-1134
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• 2024

The production of disulfide bond-containing recombinant proteins in Escherichia coli has traditionally been done by either refolding from inclusion bodies or by targeting the protein to the periplasm. However, both approaches have limitations. Two broad strategies were developed to allow the production of proteins with disulfide bonds in the cytoplasm of E. coli: i) engineered strains with deletions in the disulfide reduction pathways, e.g. SHuffle, and ii) the co-expression of oxidative folding catalysts, e.g. CyDisCo. However, to our knowledge, the relative effectiveness of these strategies has not been properly evaluated. Here, we systematically compare the purified yields of 14 different proteins of interest (POI) that contain disulfide bonds in their native state when expressed in both systems. We also compared the effects of different background strains, commonly used promoters, and two media types: defined and rich autoinduction. In rich autoinduction media, POI which can be produced in a soluble (non-native) state without a system for disulfide bond formation were produced in higher purified yields from SHuffle, whereas all other proteins were produced in higher purified yields using CyDisCo. In chemically defined media, purified yields were at least 10x higher in all cases using CyDisCo. In addition, the quality of the three POI tested was superior when produced using CyDisCo.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.115-126
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• 2015

In this study, we investigated influence of ground calcium carbonate (GCC) modified by washless multilayering of polyelectrolytes on paper quality. Three layers of polyelectrolytes (cationic starch/anionic polyacrylamide/cationic starch) were formed on the surface of GCC using laboratory inline washless polyelectrolytes multilayering system, which was called inline LbL GCC. Base papers were prepared with untreated GCC or inline LbL GCC using a laboratory handsheet former. These handsheets were coated with rod coater, and then printed by black ink. Properties of base paper and fold crack of coated paper were evaluated. Base paper with inline LbL GCC showed much higher mechanical strength in terms of tensile index, strain, internal bond strength, and folding endurance. The fold crack of coated paper with inline LbL GCC occurred more frequently compared to coated paper with untreated GCC. This might be due to highly improved internal bond strength of base paper, which resulted in smaller delamination that played a role of stress dissipation. It would be recommended to design a proper coating layer in order to prevent fold crack.

• Journal of the Korean Wood Science and Technology
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• v.45 no.1
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• pp.62-71
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• 2017

This study was investigated on the properties of board made from carbonized rice husk differed in density of board, resin addition ratio and sawdust addition ratio. Water absorption is showed the lowest value to 80.09% when the resin addition ratio of 25%, as the density increased and sawdust addition ratio decreased, the water absorption was decreased. The measured thickness swelling satisfied with the quality standards of KS F 3104, so the feasibility of building interior has been confirmed in the dimensional stability. In case of resin addition ratio of 25%, the internal bond strength was satisfied quality standards of KS F 3104 to $0.244N/mm^2$. With increasing the density, resin and sawdust addition ratio, brinell hardness increased.

• Journal of Wellbeing Management and Applied Psychology
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• v.3 no.2
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• pp.13-20
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• 2020

The purpose of this study was to empirically investigate the relationship among fashion brand experience, brand loyalty, relationship quality, and repurchase intention. The 420 survey questionnaires were distributed among the consumers in their 30s and 40s who had experience buy fashion brands products through convenience sampling in Seoul. Due to the reliability of data, 120 samples were discarded and 300 samples were put to actual analysis. By using SAS 9.4, data were analyzed for frequency analysis, reliability analysis, correlation analysis. The results of the study are as follows. First, the fashion brand experience which is consist of sensory, affective, behavioral and intellectual experience had positive effects on brand satisfaction and brand trust. Second, brand trust and brand commitment and the relationship quality of brand satisfaction, only satisfaction and commitment affects brand loyalty significantly. Lastly, brand loyalty had significantly effect on repurchase intention. It presented the potential to use the brand as a strategic tool to build strong brand assets, along with providing specific ways to secure differentiated competitiveness in the fashion brand market. It is also thought to be meaningful in that we presented a practical strategy to build and strengthen a lasting bond with consumers by looking at the impact on the quality of the relationship.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.160-163
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• 2004

In domestic, various repair materials and method systems to keep up with these reinforced concrete deteriorated due to salt damage, carbonation, chemical decay et. developed and applied. However, on-site quality control of various repair materials and method systems isn't achieved desirably because it is depend completely on a men of experience' opinions above all else regardless of various on-site environments. In this background, mock up test with due regard to real on-site environments was performed to secure fundamental data for establishment of desirable on-site quality control. Mock up test using repair mortar analyzed from angles of construction methods, mechanical spraying pressures, W/M. Construction methods were designed manpower method and spraying method, spraying pressures were designed 32, 42, 52 psi, W/M were designed 14.4, 15.4, $16.4\%$. And compressive strength, Chloride ion diffusion coefficient, bond strength, SEM. of mock up test specimens were evaluated. In conclusion, we confirmed excellency of mechanical spraying pressures, fined extremely excellency of condition of spraying pressure 42 ps, W/M $14.4\%$ within this study. therefore the results of this study will be useful to provide fundamental data for establishment of desirable on-site quality control.

• International Journal of Concrete Structures and Materials
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• v.10 no.1
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• pp.87-97
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• 2016

In this study, a quantitative review was performed on the mechanical performance, permeation resistance of concrete, and durability of surface-modified coarse aggregates (SMCA) produced using low-quality recycled coarse aggregates, the surface of which was modified using a fine inorganic powder. The shear bond strength was first measured experimentally and the interface between the SMCA and the cement matrix was observed with field-emission scanning electron microscopy. The results showed that a reinforcement of the interfacial transition zone (ITZ), a weak part of the concrete, by coating the surface of the original coarse aggregate with surface-modification material, can help suppress the occurrence of microcracks and improve the mechanical performance of the aggregate. Also, the use of low-quality recycled coarse aggregates, the surfaces of which were modified using inorganic materials, resulted in improved strength, permeability, and durability of concrete. These results are thought to be due to the enhanced adhesion between the recycled coarse aggregates and the cement matrix, which resulted from the improved ITZ in the interface between a coarse aggregate and the cement matrix.