Fluence, depth absorbed dose and linear energy transfer (LET) distributions of proton and carbon ion beams have been investigated using the Monte Carlo code Geant4 (GEometry ANd Tracking). An open source application was developed with the aim to simulate two typical transport beam lines, one used for ocular therapy and cell irradiations with protons and the other for cell irradiations with carbon ions. This tool allows evaluation of the primary and total dose averaged LET and predict their spatial distribution in voxelized or sliced geometries. In order to reproduce the LET distributions in a realistic way, and also the secondary particles' contributions due to nuclear interactions were considered in the computations. Pristine and spread-out Bragg peaks were taken into account both for proton and carbon ion beams, with the maximum energy of 62 MeV/n. Depth dose distributions were compared with experimental data, showing good agreement. Primary and total LET distributions were analysed in order to study the influence of contributions of secondary particles in regions at different depths. A non-negligible influence of high-LET components was found in the entrance channel for proton beams, determining the total dose averaged LET by the factor 3 higher than the primary one. A completely different situation was obtained for carbon ions. In this case, secondary particles mainly contributed in the tail that is after the peak. The results showed how the weight of light and heavy secondary ions can considerably influence the computation of LET depth distributions. This has an important role in the interpretation of results coming from radiobiological experiments and, therefore, in hadron treatment planning procedures.

Hadrontherapy is a C++ , free and open source application developed using the Geant4 Monte Carlo libraries. The basic version of Hadrontherapy is contained in the official Geant4 distribution (www.cern.ch/Geant4/download), inside the category of the advanced examples. This version permits the simulation of a typical proton/ion transport beam line and the calculation of dose and fluence distributions inside a test phantom.A more complete version of the program is separately maintained and released by the authors and it offers a wider set of tools useful for Users interested in proton/ion-therapy studies. It gives the possibility to retrieve ion stopping powers in arbitrary geometrical configuration, to calculate 3D distributions of fluences, dose deposited and LET of primary and of the generated secondary beams, to simulate typical nuclear physics experiments, to interactively switch between different implemented geometries, etc.In this work the main characteristics of the actual full version of Hadrontherapy will be reported and results discussed and compared with the available experimental data.For more information the reader can refer to the Hadrontherapy website.

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The a i m of the present work is to propose a way to identifl the behaviour of am induction motor supplied by using a DC/AC converter controlled thraugh a Pulse Width Modulation (PWM) technique. Although a mathematical description of' the motor is wellknown in literature, the model is sensitive to parameters variati0.n~. Moreover it lis impossible to modellize in a mathematical way the system composed by the motor and the inverter together. A Neuro Fuzzy Network, trained with a set of VO mtwmes, it is able to identie the whole system. The results proposed show how the behaviour of the identified system matches the real one.