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Choi, Hae-Young;Song, Jung-Ah
- Journal of the Korean Home Economics Association
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- v.44 no.1 s.215
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- pp.47-58
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- 2006
The purposes of this research were to evaluate the effects of the sex education program on sexual knowledge and sexual attitude, and to provide fundamental information on sex education for middle school students. The research design was comparison and experimental groups including pre-test and post-test. The study subjects were 160 male middle school students in Pusan: 80 students of the experimental group and 80 students of the comparison group. The experimental group showed the significant differences from the comparison group in terms of sexual knowledge and sexual attitude. Through formative evaluation, students recognized human sexuality, especially in the areas of physical change, psychological change, dating, sexual drives and sexual violence. This sexual education program was designed with literature review and participated students' requests.
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Kim, Yeon-Hee;Lee, Si-Young
- International Journal of Oral Biology
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- v.36 no.4
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- pp.163-166
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- 2011
Oral viridans streptococci are recognized as one of the etiological agents of a variety of infectious diseases such as dental caries and infective endocarditis. Although antimicrobial susceptibility tests for these fastidious bacterial species are now established and standardized, a comparison between the broth microdilution and broth macrodilution tests has not previously been performed. This comparison was performed in the present study using the tests adopted by the Clinical and Laboratory Standards Institute (CLSI) and seven clinical isolates of oral viridans streptococcal strains. A modified broth macrodilution susceptibility test method was also included in this analysis, in which the media was not supplemented with horse blood. The susceptibility interpretation category agreements were measured at 83% (broth microdilution versus broth macrodilution) and 71% (broth microdilution versus modified broth macrodilution). The interpretation category agreement between the broth macrodilution and modified broth macrodilution tests was also 83%. These data indicate that the interpretation of antibiotic susceptibility test results for oral viridans streptococci are influenced by the methods used.
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Kang, Tahyun;Suh, Yongsug
- Proceedings of the KIPE Conference
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- 2015.07a
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- pp.357-358
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- 2015
This paper provides a comparison of power converter loss and thermal description for voltage source and current source type 5MW-class medium voltage topologies of wind turbines. Neutral-point clamped three-level converter is adopted for voltage source type topology while two-level converter is employed for current source type topology considering the popularity in the industry. In order to match the required voltage level of 4160V with the same switching device of IGCT as in voltage source converter, two active switches are connected in series for the case of current source converter. The loss analysis is confirmed through PLECS simulations. In addition, the loss factors due to di/dt and dv/dt snubber and ac input filter are presented. The comparison result shows that VSC-based wind turbine system has a higher efficiency than that of CSC under the rated operating conditions.
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