beamtransportinavoxelizedhumanphantommodel

beamtransportinavoxelizedhumanphantommodel内容摘要：

tside beam edge  P3 (2 iter) better agreement  P3 (1 iter) slightly better agreement  Again P3 (1 and 2 iter) better agreement purely fortuitous OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 10 Fractional Frequency Distribution of Voxel Flux Differences in MC Standard Deviations 00 . 0 20 . 0 40 . 0 60 . 0 80 . 10 . 1 20 . 1 4 2 5 2 0 1 5 1 0 5 0 5 10p 5 f u l lp 5 2 i t e rp 5 1 i t e rp 3 f u l lp 3 2 i t e rp 3 1 i t e rMC Standard Deviations  TORT Calculations  P5 (full) tightly clustered at 0 MC SD’s  P5 (2 iter) clustered at 5 MC SD’s  P5 (1 iter) much larger spread at 15 MC SD’s  P3 (full) slightly less clustered at 0 MC SD’s  P3 (2 iter) slightly less clustered at 5 MC SD’s  P3 (1 iter) similar to P5 (1 iter) distribution  Small number of iters results in less scattering – therefore less particles of all energies outside beam resulting smaller total tracklengths OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 11 Fractional Frequency Distribution of Voxel Energy Deposited Differences in MC Standard Deviations MC Standard Deviations 0 . 0 00 . 0 10 . 0 20 . 0 30 . 0 40 . 0 50 . 0 60 . 0 70 . 0 80 . 0 9 1 5 1 0 5 0 5 10 15 20 25p 5 f u l lp 5 2 i t e rp 5 1 i t e rp 3 f u l lp 3 2 i t e rp 3 1 i t e r TORT Calculations  P5 (full) tightly clustered at 0 MC SD’s  P5 (2 iter) also tightly clustered at 5 MC SD’s  P5 (1 iter) clustered less at ~ 2 MC SD’s  P3 (full) larger spread at ~ 5 MC SD’s  P3 (2 iter) similar to P3 (full)  P3 (1 iter) slightly less clustered than P3(2 iter) and P3(1 iter)  Again less scattering – however high energy particles contribute more to energy deposition thus effect of less scattering is reduced  P5 (2 iter) may be adequate ? OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY 12 Comparison of CPU Times: TORT vs EGSnrc C P U T i mes R eq u i r ed f o r D i scr ete Ord i n a tes a n d M C C a l cu l a ti o n s Code Calc ul atio n CPU T im e ( m in ut e s) P h o ton F l u x 88 E G S n rc E n ergy D ep o si ted 5000 P 3 1 it e r at ion 23 P 3 2 it e r at ion 35 T OR Ta P 3 f ul l y c onve r ge d 185 P 5 1 it e r at io n 62 P 5 2 it e r at ion 97 T OR Ta P 5 f ul l y c onve r ge d 570 aI n clu d es GR T UN CL 3 D C PU ti m es o f 5 a n d 1 2 m in u te s fo r P3 a n d P5 ca lcu lat ion s , re s p ect ively .。