• Journal of the Korean Society for Precision Engineering
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• v.15 no.9
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• pp.145-151
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• 1998

In this study, the experimental and analytic investigation with cold air system has been performed for improving the working environment of the conventional grinding fluid. Very simple cold air system was developed which could replace by the conventional grinding fluid system. The identification of heat of grinding Bone is very important for precision grinding. The experimental data was analysed to investigate the heat which was transferred to the workpiece. It was found that 45∼55％ of the total energy for dry grinding, 22∼28％ for wet grinding, and 32∼35％ for cold air system are conducted to the workpiece in grinding with cubic boron nitride wheel. Cubic boron nitride wheel could reduce the residual stress and thermal demage comparing with aluminium oxide wheel, because cubic boron nitride wheel has very high extreme thermal conductivity.

• Journal of Sensor Science and Technology
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• v.32 no.1
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• pp.31-38
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• 2023

Three-dimensional (3D) micro/nanostructures based on soft elastomers have received extensive attention in recent years, owing to their potential and advanced applicability. Designing and fabricating 3D micro/nanostructures are crucial for applications in diverse engineering fields, such as sensors, harvesting devices, functional surfaces, and adhesive patches. However, because of their structural complexity, fabricating soft-elastomer-based 3D micro/nanostructures with a low cost and simple process remains a challenge. Bio-inspired designs that mimic natural structures, or replicate their micro/nanostructure surfaces, have greatly benefited in terms of low-cost fabrication, scalability, and easy control of geometrical parameters. This review highlights recent advances in 3D micro/nanostructures inspired by nature for diverse potential and advanced applications, including flexible pressure sensors, energy-harvesting devices based on triboelectricity, superhydrophobic/-philic surfaces, and dry/wet adhesive patches.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.166-167
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• 2013

Bottom ash, which is discharged through a wet process in a thermal power plant, contains much unburned coal due to quenching and much salt due to seawater. However, dry bottom ash discharged through a dry process contains low unburned coal and salt, and has light -weight due to many pores. Therefore, it is expected that it can be used as lightweight aggregate. This study deals with the basic properties of concrete used dry bottom ash as coarse aggregate. As a results, the concrete having high content of dry bottom ash aggregate showed high slump by using water reducing agent and its air content was within 5±1.5% as designed value, similarly to normal weight concrete. It also showed a lower compressive strength than 100% of crushed stone.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.6
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• pp.693-703
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• 2008

The important source of the mercury in water-column is the influx of atmosphere mercury, via dry and wet deposition. In this study, wet deposition of mercury was estimated to be $14.56{\mu}g/m^2$ during 15 months at the Lake Soyang, which is a little higher than those observed in the several rural US Mercury Deposition Network (MDN) sites with similar precipitation depth. The mercury concentration in precipitation did not show a positive correlation with atmospheric RGM (reactive gaseous mercury) concentration, while maintaining good correlation with atmospheric $PM_{2.5}$ at Soyang Dam. This result suggests that the contribution of particulate Hg to the total Hg wet deposition should be more significant than that of RGM. In this study, both precipitation depth and precipitation type affected the amount of wet deposition and the concurrent mercury levels in precipitation. There was generally an inverse relationship between precipitation depth and Hg concentration in precipitation. Precipitation type was another factor that exerted controls on the Hg concentration in precipitation. As a result, the highest concentration of Hg was observed in snow, followed by in mixture (snow+rain) and in rain.

• Journal of the Korea Computer Graphics Society
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• v.25 no.1
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• pp.1-11
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• 2019

More force must be applied when dragging a wet compared with a dry cloth lying on the table. Increased force is needed because the fluid between the cloth and the surface of the table produces an adhesion force. In this paper, we study the adhesion force between a wet cloth and the surface of an object. To compute the adhesion force, we used the adhesion force model used in textile research based on real-world experiments and also considered the effect of wrinkles, which, to our knowledge, has not been investigated in previous work. Furthermore, we studied the phenomenon in which a wet cloth adheres to the surface of an object and that in which a wet cloth adheres to itself when undergoing self-collision.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.286-288
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.222.2-222
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• 2001

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.05a
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• pp.21-22
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• 1999

• KSBB Journal
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• v.7 no.2
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• pp.144-148
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• 1992

The purpose of this study is to develop a continuous process for sorbitol production using dried Zymomonas mobilis immobilized in K-carrageenan. The methods of glularaldehyde cross-linking of enzymes in CTAB (celyltrimetylammoniumbromide) treated cells immobilized in K-carrageenan showed stability for the production of sorbitol for 30 days of operation. K-carrageenan beads entrapping permeabilized cells were dried to Improve bead rigidity and storage stability. A semi-batch process with dry beads was carried out and only a small loss of enzyme activity (less than 8%) was observed during 72h. The value of Vmax for the dry K-carrageenan beads was found to be one half or that for free cells. It was shown that the productivities of the continuous process with wet K-carrageenan beads and dry beads at a dilution rate 0.1h-1 were 3.4g/L-h and 2.88h/L-h, respectively.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.36-42
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• 1996

The production of sorbitol by permeabilized cells of Zymomonas mobilis immobilized in $\kappa$-carrageenan was investigated. Cetyltrimethylammoniumbromide (CTAB) permeabilized cells were treated with glutaraldehyde prior to immobilization for cross-linking of enzymes, glucose-fructose oxidoreductase (GFOR) in cells. Rigidity of the immobilized beads was increased two-fold with 90$\%$ conversion efficiency by the additions of 40$\%$ (w/v) polyols (glycerol 25 g + propylene glycol 15 g) to 60$\%$ (w/v) distilled water containing 2.5$\%$ (w/v) $\kappa$-carrageenan as a final concentration, prior to immobilization. $\kappa$-Carrageenan beads entrapping permeabilized cells were dried to improve bead rigidity and storage stability. During s6mi-batch process for 72 h with dry beads, there was an improvement of the loss of enzyme activity (less than 10$\%$). In batch process, the kinetic results of $K_m.fructose$ value for the free cells, wet beads and dry $\kappa$-carrageenan beads were 71.7, 72.4 and 116.7 g/l, respectively. Higher productivity was obtained with two-stage continuous packed bed reactors with both wet and dry $\kappa$-carrageenan beads at 25.00 and 21.15 g/l/h, respectively, when measured at second stage.