14 research outputs found

    カテイカ ニ オケル タイケンテキ ガクシュウ 1 : ダイガク キョウカン グン ト シドウ シュジ グン トノ ニンシキ ノ ヒカク

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    An opinion survey was conducted on experience-centered curriculums for homemaking education at senior high schools. The subjects were 57 professors from 47 universities and 34 teacher's consultants from 34 prefectures. 1. Most of the subjects, both the university staffs and the teachers' consultants, were of opinion that the experience-centered curriculums were useful for the students to heighten their thinking and practical abilities in solving problems encountered in homemaking. 2. Discrepnancies were observed between the opinions of the university staffs and those of the teacher's consultants as to the contents of the curriculums, their allocation to school years or terms, and methods of evaluation and creditting

    Monte Carlo calculations of correction factors for plastic phantoms in clinical photon and electron beam dosimetry

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    The purpose of this study is to calculate correction factors for plastic water (PW) and plastic water diagnostic-therapy (PWDT) phantoms in clinical photon and electron beam dosimetry using the EGSnrc Monte Carlo code system. A water-to-plastic ionization conversion factor k(pl) for PW and PWDT was computed for several commonly used Farmer-type ionization chambers with different wall materials in the range of 4-18 MV photon beams. For electron beams, a depth-scaling factor c(pl) and a chamber-dependent fluence correction factor h(pl) for both phantoms were also calculated in combination with NACP-02 and Roos plane-parallel ionization chambers in the range of 4-18 MeV. The h(pl) values for the plane-parallel chambers were evaluated from the electron fluence correction factor phi(pl)w and wall correction factors P(wall,w) and P(wall,pl) for a combination of water or plastic materials. The calculated k(pl) and h(pl) values were verified by comparison with the measured values. A set of k(pl) values computed for the Farmer-type chambers was equal to unity within 0.5% for PW and PWDT in photon beams. The k(pl) values also agreed within their combined uncertainty with the measured data. For electron beams, the c(pl) values computed for PW and PWDT were from 0.998 to 1.000 and from 0.992 to 0.997, respectively, in the range of 4-18 MeV. The phi(pl)w values for PW and PWDT were from 0.998 to 1.001 and from 1.004 to 1.001, respectively, at a reference depth in the range of 4-18 MeV. The difference in P(wall) between water and plastic materials for the plane-parallel chambers was 0.8% at a maximum. Finally, h(pl) values evaluated for plastic materials were equal to unity within 0.6% for NACP-02 and Roos chambers. The h(pl) values also agreed within their combined uncertainty with the measured data. The absorbed dose to water from ionization chamber measurements in PW and PWDT plastic materials corresponds to that in water within 1%. Both phantoms can thus be used as a substitute for water for photon and electron dosimetry
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