Children are a susceptible group to environment pollution. The environment, in which they spend the most time, is the home, the second is the school. Therefore, the indoor environment of a school affects their health, wellbeing and even school results. The present work investigated concentrations of air pollutant, aerosol particles, in the specialized classrooms (computer lab, arts and biology/chemistry) in an elementary school, Prague. Direct reading instruments measuring mass concentration of four aerosol fractions and number concentration of submicrometer particles were used for measurement. Measurements were carried out for four weekdays in each month from November 2011 to July 2012. It was found that mass concentrations of submicrometer particles were dependent on outdoor concentrations, in contrast to supermicrometer particles which were affected mainly by physical activities of students and outdoor concentration had a minimal effect. Increased number concentrations of submicrometer particles were observed only during children presence, concentrations were probably induced by student activities during lessons. Seasons also influenced mass concentrations, when the highest indoor and outdoor concentrations were recorded in a spring/autumn season. Classroom location affected submicrometer...

This diploma thesis deals with reduction of metal artifacts in CT data with submicron resolution. The first part of this thesis briefly describes x-ray computed tomography followed by the description of artifacts of tomographic images and existing approaches of the reduction of metal artifacts. In the second part proposed methods of reduction of metal artifacts and their implementation in Matlab programming environment are described. Finally functionality of algorithms is tested on a newly created database and the results are compared, evaluated and discussed.