A critical infrastructure is a complicated system whose failure (in whole or in part) has a significant impact on national interests, including security, the economy and basic human needs. The system consists of relevant sectors, elements and their mutual linkages. In order to study critical infrastructures, it is necessary to apply a systems approach based on cross-sectoral evaluation and research into the linkages between the individual critical infrastructure sectors. Specifically, it is necessary to describe the individual vertical and horizontal levels of each critical infrastructure and the associated linkages. From this point-of-view, a critical infrastructure is embedded within the broader context of emergencies and enterprises, representing a compact and mutually-interconnected system.This paper focuses on quantitatively assessing the impacts of critical infrastructure failures. It presents a theory of synergistic linkages, their levels and the synergistic effects due to the joint action of impacts, which increase the overall impact on the critical infrastructure and on society. The concepts are formalized in the SYNEFIA methodology, which is applied in a case study involving the critical infrastructure of the Czech Republic. In particular, the methodology is applied to determine the synergistic effects of disruptions to multiple sub-sectors of the Czech infrastructure

The paper deals with the measurement and identification of surfaces after machining in a non-contact manner. It presents a new modified measurement method and its implementation, the results of intensity distribution in the defocusing plane, their analysis and interpretation. The scanned intensity distribution at the defocusing plane gives information necessary to assess the second derivatives, and thus, surface functions which can be used to determine groove curvatures of the real surface morphology. The proposed method of measurement has proved to be very sensitive in evaluating the differences between surface finishing methods by which the measured surface standards (etalons) were machined. Two methods of machining were chosen: face grinding and planning. By comparing the roughness standard values Ra, there were obtained relationships between these values and the parameter of the characteristic frequency of vertical inequality being measured according to the presented method. A good correlation between the measured and surface standard values with the correlation coefficient taking a range of values from 0.8 to 1 was achieved.Web of Science12518818