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Table 12 W[QMYZ$CFHkQ,kphant Table 13 2,. D"5 Standard Dose Head Pelvis 100kV 20mA 20msec 120kV 80mA 13msec µ enρ 4.33 mGy 28.41 mGy ND,WQ 4.19 mGy 28.03 mGy difference -3.23 % -1.34 % ) IGRT IGRT ) DRLs 1 IGRT-QA/QC Working group report,2012 2 QA/QC . ( :IGRT ). 2010; 30: 49-53. 3 Palm A, Nilsson E and Herrnsdorf Lars Herrnsdorf , Absorbed dose and dose rate using the Varian OBI 1.3 and 1.4 CBCT system. Journal of Applied Clinical Medical Physics, 11, 229-40,2010 4 , (25) ,2006 5 http://physics.nist.gov/PhysRefData/XrayMassCoef/ElemTab/z13.html 2017 3 25 6 C.M. Ma, C. W. Coffey, L. A. DeWerd, C. Liu, R. Nath, S. M. Seltzer, J. P. Seuntjens, “AAPM protocol for 40-300 kV x-ray beam dosimetry in radiotherapy and radiobiology”, Med. Phys. 28, 868-893 ,2001. 7 Grosswendt, B., Dependence of the photon backscatter factor for water on source-to-phantom distance and irradiation field size. Phys. Med. Biol. 35, 1233-1245,1990 8 Klevenhagen, S.C., Experimentally determined backscatter factors for X-rays generated at voltages between 16 and 140 kV. Phys. Med. Biol. 34, 1871-1882.,1989. 9 , X 57(12),1503-1510,2001 10 (J-RIME)/ ± ,2015.6.7 11 Varian medical systems, Dose in CBCT – OBI Advanced Imaging. On-Board Imager® (OBI) kV imaging system v1.4 and v1.5. Revision 1.3. Jun , 2012. 12 Varian Customer Technical Bulletin OB-885 Rev A 13 , (33) ,2015