An axisymmetric, Navier-Stokes finite volume flow solver, which uses Harten, Lax and van Leer (HLL) and Harten, Lax and van Leer&ndash / Contact (HLLC) upwind flux differencing scheme for spatial and uses Runge-Kutta explicit multi-stage time stepping scheme for temporal discretization on unstructured meshe is developed. Developed solver can solve the compressible axisymmetric flow. The spatial accuracy of the solver can be first or second order accurate. Second order accuracy is achieved by piecewise linear reconstruction. Gradients of flow variables required for piecewise linear reconstruction are calculated by Green-Gauss theorem. Baldwin-Lomax turbulent model is used to compute the turbulent viscosity. Approximate Riemann solver of HLL and HLLC implemented in solver are validated by solving a cylindrical explosion case. Also the solver&rsquo / s capability of solving unstructured, multi-zone domain is investigated by this problem. First and second order results of solver are compared by solving the flow over a circular bump. Axisymmetric flow in solid propellant rocket motor is solved in order to validate the axisymmetric feature of solver. Laminar flow over flat plate is solved for viscous terms validation. Turbulent model is studied in the flow over flat plate and flow with mass injection test cases.

The screening mammography programme has been running succesfully in the Czech republic for 13 years. Due to its ability to uncover earlystages of breast cancer, it helps to fight this serious disease. Although the positive outcome of this programme in the Czech republic has been already proved, there is only approximately 50% of women who have been regularly treated with it.One of the major reasons for this fact is a fear of cancer induction caused by the use of X-rays during the mammography. The main goal of this thesis is to calculate the risk of breast cancer induction caused by the mammography and to compare benefits of the screening programme for a woman who goes for regular checkups and a woman who does not. The measurement of concrete doses was made in one screening centre center located in western bohemia region. The group of observed patients at the age of 45-59 was divided into three categories. The object of measurement was an average dose received during the screening mammography, plus an average dose received during an additional mammography, which may sometimes occure during the examination. These data was studied through a statistic investigation to prove that the received dose is not dependent on the patient´s age. In the theoretical part of this work main principals of the screening mammography programme and mammography itself are repeated. The methods of statistic investigation and the methodology for estimating breast cancer risks based on recommendations of ICRP Publication 103. In the practical part was proved, that the average dose received during the classical mammography does not depend on the age of the patient. This could not be proved for an additional mammography dose, because of not sufficient group of statistic data. The main hypothesis, that regular checkups using the mammographical screening programme is benefical for women , was verified.