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Noh, Kyung-Min;Sung, Yun-Mo
- Korean Journal of Materials Research
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- v.18 no.12
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- pp.669-672
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- 2008
Well-aligned Zinc oxide (ZnO) nanowires were synthesized on silicon substrates by a carbothermal evaporation method using a mixture of ZnO and graphite powder with Au thin film was used as a catalyst. The XRD results showed that as-prepared product is the hexagonal wurzite ZnO nanostructure and SEM images demonstrated that ZnO nanowires had been grown along the [0001] direction with hexagonal cross section. As-grown ZnO nanowires were coated with glucose oxidase (GOx) for glucose sensing. Glucose converted into gluconic acid by reaction with GOx and two electrons are generated. They transfer into ZnO nanowires due to the electric force between electrons and the positively charged ZnO nanostructures in PBS. Photoluminescence (PL) spectroscopy was employed for investigating the movements of electrons, and the peak PL intensity increased with the glucose concentration and became saturated when the glucose concentration is above 10 mM. These results demonstrate that ZnO nanostructures have potential applications in biosensors.
https://doi.org/10.3740/MRSK.2008.18.12.669 인용 PDF KSCI

Kaveh, A.;Shokohi, F.
- Structural Engineering and Mechanics
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- v.58 no.3
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- pp.533-553
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- 2016
In this paper, the recently developed meta-heuristic algorithm called tug of war optimization is applied to optimal design of castellated beams. Two common types of laterally supported castellated beams are considered as design problems: beams with hexagonal openings and beams with circular openings. Here, castellated beams have been studied for two cases: beams without filled holes and beams with end-filled holes. Also, tug of war optimization algorithm is utilized for obtaining the solution of these design problems. For this purpose, the minimum cost is taken as the objective function, and some benchmark problems are solved from literature.
https://doi.org/10.12989/sem.2016.58.3.533 인용 KSCI

Choi, Won-Sik;Umehara, Noritsugu
- Tribology and Lubricants
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- v.27 no.5
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- pp.264-268
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- 2011
In this study, we examined the friction characteristics of a dimple pattern on a carbon nitride coating. The study was conducted with a hexagonal array 40 ${\mu}m$ dimple pattern on a steel bearing containing a CNx coating. The area density of the dimple patterns were varied between 5% and 25%, the speed was varied from 0.06-0.26 m/s, and the load was varied between 20-100N. In general, we found that as the velocity increased, the friction coefficient increased. Furthermore, the friction coefficient was lowest at a load of 40N. The friction coefficient of the non-coated specimen was 0.025-0.15; on the other hand, the friction coefficient of the coated specimen was 0.002-0.02. Thus, we determined that the coated materials could reduce the friction coefficient by a factor of 7.5.
https://doi.org/10.9725/kstle.2011.27.5.264 인용 PDF KSCI