• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.472-477
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• 2004

Miniaturization is the central theme in modern fabrication technology. Many of the components used in modem products are becoming smaller and smaller. The direct write FIB technology has several advantages over contemporary micromachining technology, including better feature resolution with low lateral scattering and capability of mastless fabrication. Therefore, the application of focused ion beam(FIB) technology in micro fabrication has become increasingly popular. In recent model of FIB, however the feeding system has been a very coarse resolution of about a few ${\mu}{\textrm}{m}$. It is not unsuitable to the sputtering and the deposition to make the high-precision structure in micro or macro scale. Our research is the development of nano stage of 200mm strokes and l0nm resolutions. Also, this stage should be effectively operating in ultra high vacuum of about 1$\times$10$^{-5}$ pa. This paper presents the concept of nano stages and the discussion of the material treatment for ultra tush vacuum.

• Journal of the Korean Society for Heat Treatment
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• v.15 no.6
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• pp.269-271
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• 2002

For the investigation of the hardness profiles and distortion characteristics of SCM415 steel, test pieces of SCM415 steel were gas and vacuum carburizing treated. The hardness profiles and distortion characteristics of vacuum and gas carburized SCM415 steel show different results. Vacuum carburizing can offer more improved hardness profiles than alternate methods of carburizing. Compared to alternate methods of carburizing, vacuum carburizing can offer improved mechanical properties and reduced cycle times of the process.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.4
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• pp.199-202
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• 2011

Ga doped ZnO thin films were deposited with RF magnetron sputtering on glass substrate without intentional substrate heating and then the effect of post deposition annealing temperature on the structural, optical and electrical properties of the films was investigated. The post deposition annealing process was conducted for 30 minutes in a vacuum of $1{\times}10^{-3}$ Torr and the vacuum annealing temperatures were 150 and $300^{\circ}C$, respectively. As increase annealing temperature, GZO films show the increment of the prefer orientation of ZnO (002) diffraction peak in the XRD pattern and the optical transmittance in a visible wave region was also increased, while the electrical sheet resistance was decreased. The figure of merit obtained in this study means that GZO films which vacuum annealed at $300^{\circ}C$ have the highest optoelectrical performance in this study.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.466-472
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• 2013

This study was performed to determine the effects of the pretreatment and cold-vacuum drying methods on the physicochemical properties and antioxidant activities of dried peaches. Moisture content was significantly lower with 0.3% NaCl treatment with cold-vacuum drying. The pH, brix and acid ratio (SS/TA) were the lowest with 1.0% soluble Ca treatment, while soluble solid and SS/TA were significantly higher with 0.1% vitamin C treatment compared to those with other treatments. The ${\delta}E$ and browning degree was lower in the pretreated sample compared to the untreated sample. Cutting strength of dried peaches was highest in the pretreated samples, and it was the highest with 1.0% soluble Ca treatment. Total sugar content with 0.1% vitamin C and 1.0% soluble Ca treatment was significantly higher than that with 0.3% NaCl treatment. The free sugar content was lower with 0.3% NaCl treatment but it was higher with 0.1% vitamin C and 1.0% soluble Ca treatment. The sensory evaluation result was highest with 0.1% vitamin C treatment. Phenolic compounds and antioxidant ability were the highest with the 0.1% vitamin C and 0.1% soluble Ca treatment; all the dried peaches showed relatively high antioxidant activities. These results suggest that pretreatment can affect the quality of dried peaches, showing that cold-vacuum drying can be applied for the production of high quality dried peach products.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.792-797
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• 2015

In this study, three softwood species were treated with water-soluble melamine resin by different concentration and treatment time under vacuum pressure for improving mechanical property, abrasion resistance, and incombustibility. After the treatment, a compreg was manufactured and then evaluated on physical properties. Additionally, incombustibility of compreg was determined by comparing with a wood that was treated by spraying a water-soluble fire retardant on surface. As concentration of resin increased, bending strength and Brinell hardness increased as well as abrasion resistance, but there was no correlation on treatment and mechanical properties by treatment time. The wood impregnated by water-soluble melamine resin under vacuum pressure showed better incombustibility than that of a water-soluble fire retardant sprayed wood. Therefore, this treatment could be used for improving incombustibility of wood.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.5
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• pp.149-156
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• 2013

The performances of solar collectors with single and double evacuated tube were experimentally compared. The solar collector with single evacuated tube using surface treatment in this study consists of radiation fin, heat pipe, absorber plate, glass tube, cap and regulating valve, and so on. Surface treatment was conducted for heat pipe and absorber plate with black chrome plating and copper black coating. As the results, the performance of solar collector with single evacuated tube using surface treatment showed good results compared that of double evacuated tube. Absorber plate played a positive role in performance and showed increase of about 28%. Further performance depends on vacuum degree and vacuum degree has to be considered economical efficiency in solar collector.

• Proceedings of the Korean Vacuum Society Conference
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• 2001.02a
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• pp.107-107
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• 2001

• Proceedings of the Korean Vacuum Society Conference
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• 2005.02a
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• pp.90-90
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• 2005

• Proceedings of the Korean Vacuum Society Conference
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• 2009.08a
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• pp.90-90
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• 2009

• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.178.1-178.1
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• 2009