• Title/Summary/Keyword: 진동적회전

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Acquisition of High Resolution Images and its Application using Synchrotron Radiation Imaging System (방사광 X-선을 이용한 고해상도 영상획득과 응용)

  • 홍순일;김희중;정해조;홍진오;정하규;김동욱;제정호;김보라;유형식
    • Progress in Medical Physics
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    • v.12 no.1
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    • pp.51-58
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    • 2001
  • Synchrotron radiation (SR) has several advantages over convetional x-rays, including its phase, collimation, and high flux. A synchrotron radiation beamline 5C1 at Pohang Light Source (PLS) was recently built for imaging applications. We have shown that a SR imaging system is useful in imaging microscopic structures. SR with broad-band energy spectrum were adjusted to an object by Si wafers and their energy were approximately ranging from 6 keV to 30 keV. SR were passed through an object and finally transformed into visible lights by CdWO$_4$ scintillator screen. The visible lights which were reflected at an angle of 90 degrees by gold plated mirror were detected by a CCD camera and the image data were acquired using image acquisition system. A high-resolution phantom, capacitor, adult tooth, child tooth, cancerous breast tissue, and mouse lumbar vertebra were imaged with SR imaging system. The Objects were rotated within the field of view of the CCD detector, and their projection image data were obtained at 250 steps over 180 degrees rotation. Image reconstructions were carried out in a PC by using IDLTM(Research systems, Inc., US) program. The spatial resolution of the images acquired by the SR imaging system was measured with a high-resolution chart manufactured for several micrometer resolution. The specimens were also imaged with conventional x-ray radiography system to compare the image quality of radiography obtained with the SR imaging system. The results showed more structural details and high contrast images with SR imaging system than conventional x-ray radiography system. The SR imaging system may have a potential for imaging in biological researches, material applications, and clinical radiography.

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Subjective Oral Health Behaviors and Recognition of Childcare Teacher With and Without Oral Health Education (보육교사의 구강보건교육경험유무에 따른 구강보건행태 및 인지도)

  • Jang, Kyeung-Ae;Seong, Mi-Kyung
    • Journal of dental hygiene science
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    • v.9 no.3
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    • pp.319-326
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    • 2009
  • The purpose of this study was to examine the Influence of the experience of Childcare Teacher about oral health education on oral health behaviors. For this, Questionnairs to be self-filled up about experience of oral health education were carried out to 267 childcare teachers who are working in nurseries in Geongnam province. The date was analysed using the SPSS 12.0 program. The obtained result were as follows. Among the respondents who are not under stress of oral health. 8.1% respondents had the oral health education and 7.7% others didn't have it. For toothbrushing methods, it was found that 25.3% used manual toothbrushing with experience in dental education(up and down toothbrushing monement) and 35.4% used semi automatic toothbrushing(rotational movement). 37.1% respondents had experiences in oral health education, 69.7% respondents were instructed in the oral health at public health center, and 61.6% respondents were instructed in the oral health a theory(toothbrushing guidance). Among the respondents who answered that oral health education should be necessary, 83.4% of those have already had oral health education where as 73.8% respondents have not had the education. 67.7% of the respondents who want to participate in the oral health education is corresponding to those with experience in dental education, 66.1% respondents with no education feel the necessity of the oral health education.

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