Purpose: The idea for this project was born by the necessity to offer medical students an easy approach to the theoretical basics of magnetic resonance imaging. The aim was to simulate the features and functions of su...
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Purpose: The idea for this project was born by the necessity to offer medical students an easy approach to the theoretical basics of magnetic resonance imaging. The aim was to simulate the features and functions of such a scanner on a commercially available computer by means of a computer program. Materials and Methods: The simulation was programmed in pure Java under the GNU General Public License and is freely available for a commercially available computer with Windows, Macintosh or Linux operating system. The graphic user interface is oriented to a real scanner. In an external program parameter, images for the proton density and the relaxation times T1 and T2 are calculated on the basis of clinical examinations. From this, the image calculation is carried out in the simulation program pixel by pixel on the basis of a pulse sequence chosen and modified by the user. The images can be stored and printed. In addition, it is possible to display and modify k-space images. Results: Seven classes of pulse sequences are implemented and up to 14 relevant sequence parameters, such as repetition time and echo time, can be altered. Aliasing and motion artifacts can be simulated. As the image calculation only takes a few seconds, interactive working is possible. Conclusion: The simulation has been used in the university education for more than 1 year, successfully illustrating the dependence of the MR images on the measuring parameters. This should facititate the approach of students to the understanding MR imaging in the future.
A new computational method using a Monte Carlo technique is described for the calculation of plausibility of paternity in blood group systems. Gene frequencies of a blood group system are simulated by the range of 7 d...
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A new computational method using a Monte Carlo technique is described for the calculation of plausibility of paternity in blood group systems. Gene frequencies of a blood group system are simulated by the range of 7 digit random numbers. By using a Monte Carlo method, 4 random numbers are generated and converted into paternal and maternal genotypes. The genotype of the child is determined according to the law of inheritance and genotypes of the father, mother and child are converted into phenotypes. Repeating this process more than 100,000 times, the phenotypic frequencies of child-mother-father combinations (trio) and the likelihood ratio of paternity in any blood group system are calculated for all phenotypic combinations of the trios. This method is easier than methods reported previously, and is sufficiently accurate.
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