Das, Taposh Kumar2013-01-252013-01-252013-01-25http://hdl.handle.net/10347/7171This work is focused on the numerical resolution of the Boltzmann transport equation (BTE) for photons and of a certain type of degenerate parabolic equations which come from the Fokker‐Planck equation. BTE is solved in the three‐dimensional case by means of the so‐called “expansion in orders of scattering”, and the degenerate parabolic equation is solved with a finite difference method. MATLAB language programming has been employed to obtain the numerical results and graphics. The motivation of the thesis is the calculus of the absorbed dose of radiation during external radiotherapy cancer treatment. The first chapters gather medical‐biological and physical information, explaining the fundamentals of radiotherapy and the interaction phenomena between radiation and matter.engEsta obra atópase baixo unha licenza internacional Creative Commons BY-NC-ND 4.0. Calquera forma de reprodución, distribución, comunicación pública ou transformación desta obra non incluída na licenza Creative Commons BY-NC-ND 4.0 só pode ser realizada coa autorización expresa dos titulares, salvo excepción prevista pola lei. Pode acceder Vde. ao texto completo da licenza nesta ligazón: https://creativecommons.org/licenses/by-nc-nd/4.0/deed.glhttps://creativecommons.org/licenses/by-nc-nd/4.0/deed.glBoltzmann transport equationabsorbed doseexternal radiotherapyphoton transportdoctoral thesisopen access