• Title/Summary/Keyword: PC 빔

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Development of 2.5D Electron Dose Calculation Algorithm (2.5D 전자선 선량계산 알고리즘 개발)

  • 조병철;고영은;오도훈;배훈식
    • Progress in Medical Physics
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    • v.10 no.3
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    • pp.133-140
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    • 1999
  • In this paper, as a preliminary study for developing a full 3D electron dose calculation algorithm, We developed 2.5D electron dose calculation algorithm by extending 2D pencil-beam model to consider three dimensional geometry such as air-gap and obliquity appropriately. The dose calculation algorithm was implemented using the IDL5.2(Research Systems Inc., USA), For calculation of the Hogstrom's pencil-beam algorithm, the measured data of the central-axis depth-dose for 12 MeV(Siemens M6740) and the linear stopping power and the linear scattering power of water and air from ICRU report 35 was used. To evaluate the accuracy of the implemented program, we compared the calculated dose distribution with the film measurements in the three situations; the normal incident beam, the 45$^{\circ}$ oblique incident beam, and the beam incident on the pit-shaped phantom. As results, about 120 seconds had been required on the PC (Pentium III 450MHz) to calculate dose distribution of a single beam. It needs some optimizing methods to speed up the dose calculation. For the accuracy of dose calculation, in the case of the normal incident beam of the regular and irregular shaped field, at the rapid dose gradient region of penumbra, the errors were within $\pm$3 mm and the dose profiles were agreed within 5%. However, the discrepancy between the calculation and the measurement were about 10% for the oblique incident beam and the beam incident on the pit-shaped phantom. In conclusions, we expended 2D pencil-beam algorithm to take into account the three dimensional geometry of the patient. And also, as well as the dose calculation of irregular field, the irregular shaped body contour and the air-gap could be considered appropriately in the implemented program. In the near future, the more accurate algorithm will be implemented considering inhomogeneity correction using CT, and at that time, the program can be used as a tool for educational and research purpose. This study was supported by a grant (#HMP-98-G-1-016) of the HAN(Highly Advanced National) Project, Ministry of Health & Welfare, R.O.K.

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가족과 함께하는 창의성 경진대회 평가연구

  • 송규운;황동주;윤정진
    • Journal of Gifted/Talented Education
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    • v.11 no.2
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    • pp.127-150
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    • 2001
  • The upcoming century is a knowledge based society which did not exist before which requires creative ability to solve problems. Therefore, it is necessary to Provide a creative program of problem solution in order to match this global trend The creativity of problem solution means the ability to solve a problem using previous ideas in an advanced way or develop new ideas. Creative education is especially important for infants. Because the young mind is where fresh ideas preside and can frame-work the early stage of life like a blank sheet of paper. The Infant-Early Child Creative Development Institute. as an adhesive institute at Yeungjin College, develops various programs that integrate methods which match current trend in this era and also start the Creative Promotion Test with 2,000 Families for the expansion of creative education from the baseline as an alternative method. The infants tested in the creative test will find ways of problem solution through animation beam projects for their given situation and also discuss the problems with their family members. Through these processes the infant and family members will complete the creative structures to solve the problems using limited materials given by the institute, and the final product will be evaluated as objective results. The final evaluation of the test will also be considered the teamwork of family cooperation and the attitudes of participants as well as the product of problem solution. The criterion of the evaluation is to be considered both a creative way of thinking and creative attitudes. Because the score counts were conducted manually it delayed the selection of awarded students who took the test. Also, we found that some parents have difficulty in accessing information to find the score through homepage from the computer. this Problem might be corrected in the future plan. Like Freud's saying, if human character and exploring attitudes during the early stage of a child, a person's creativity is composed their infant period as their basic foundation. Therefore, the family wh first environment the infant encounters will be treated as a prima when making basic structure. From this viewpoint, this creative test work as a festival of creativity fare with 2,000 families.

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