• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.5
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• pp.171-174
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• 2016

The diamond wire sawing method to produce silicon wafers for the photovoltaic application is still a new and highly investigated wafering technology. This technology, featured as the higher productivity, lower wear of the wire, and easier recycling of the coolant, is expected to become the mainstream technique for slicing the silicon crystals. However, the saw marks on the wafer surface have to be investigated and improved. This paper discusses the removal of saw marks on diamond wire-sawn single crystalline silicon wafer. With a pretreatment step using tetramethyl ammonium hydroxide ($(CH_3)_4NOH$, TMAH) and conventional texturing process with KOH solution (1 % KOH, 8 % IPA, and DI water), the saw marks on the surface of the diamond wire-sawn silicon wafers can be effectively removed and they are invisible to naked eyes completely.

• Journal of dental hygiene science
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• v.11 no.6
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• pp.481-487
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• 2011

The purpose of this study was to examine the perception of health-related majors in their third year of college about the image of a dental hygienist as prospective dental personnels. The findings of the study were as follows: 1. Concerning perception of the image of a dental hygienist by geographic region, the college students from large cities gave 89.07 to that, and the college students from small and mid-sized urban areas gave 85.03. The former gave higher marks to the image of a dental hygienist, and the gap between the two was statistically significant. By department, the students who majored in physical therapy gave the highest score of 88.93, dental technology and radiology gave the second highest score of 86.91. The clinical pathology gave the third highest score of 83.28, and the gaps among them were significant. 2. As for their perception of the four subfactors(qualifications, roles, social participation and interpersonal relationship) of the image of a dental hygienist by geographic region, there were statistically significant gaps in their way of looking at the qualifications, roles and interpersonal relationship of a dental hygienist. By department, the physical therapy majors gave the highest marks to all the four subfactors. 3. When they were asked to give one or more answers to the question what affected their image building about a dental hygienist, the largest number of the students that accounted for 67.9 percent replied that the looks of dental hygienists whom they saw in dental clinics or hospitals impacted on their image of a dental hygienist.