Odbor inženýrství rizik
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- ItemŘízení rizik vybraných prvků kritické dopravní infrastruktury(Czech Technical University in Prague, 2022-09-22) Procházková, Danuše; Procházka, Jan; Martincová, Jana Victoria; Kertis, TomášPro plnění základních funkcí státu je bezpečnost kritické infrastruktury zásadní, a proto ji musí být věnována pozornost. Dopravní infrastruktura patří do kritické infrastruktury. Její prvky: mosty; tunely; nádraží; letiště; a řízení jejich provozu, jsou zásadně důležité. Článek shrnuje zásady pro řízení rizik zmíněných prvků kritické dopravní infrastruktury založený na systémovém pojetí a respektující socio-kyberfyzickou povahu prvků a složitost systémů v dynamicky se vyvíjejícím světě.
- ItemFTIR Spectrometry with PLS Regression for Rapid TBN Determination of Worn Mineral Engine Oils(MDPI, 2020-12-05) Sejkorová, Marie; Šarkan, Branislav; Veselík, Petr; Hurtová, IvanaThe TBN (Total Base Number) parameter is generally recognized by both engine oil processors and engine manufacturers as a key factor of oil quality. This is especially true for lubricating oils used in diesel and gas engines, which are exposed to relatively high temperatures and, therefore, require more effective protection against degradation. The FTIR spectrometry method together with a multivariate statistical software helped to create a model for the determination of TBN of worn motor oil SAE 15W-40 ACEA: E5/E7, API: CI-4. The best results were provided using a model FTIR with Partial Least Squares (PLS) regression in an overall range of 4000–650 cm1 without the use of mathematical adjustments of the scanned spectra by derivation. Individual spectral information was condensed into nine principal components with linear combinations of the original absorbances at given wavenumbers that are mutually not correlated. A correlation coefficient (R) between values of TBN predicted by the FTIR-PLS model and values determined using a potentiometric titration in line with the CSN ISO 3771 standard reached a value of 0.93. The Root Mean Square Error of Calibration (RMSEC) was determined to be 0.171 mg KOH.g1, and the Root Mean Square Error of Prediction (RMSEP) was determined to be 0.140 mg KOH.g1. The main advantage of the proposed FTIR-PLS model can be seen in a rapid determination and elimination of the necessity to work with dangerous chemicals. FTIR-PLS is used mainly in areas of oil analysis where the speed of analysis is often more important than high accuracy.
- ItemNanoparticle Number Concentration in the Air in Relation to the Time of the Year and Time of the Day(MDPI, 2020-05-19) Brzezina, Jáchym; Köbölová, Klaudia; Adamec, VladimírThe paper analyzes suspended particles number concentrations of 61 size fractions (184 nm to 17,165 nm) in the air at a traffic location. The average course of the individual fractions was analyzed at various intervals - daily, weekly, monthly and annually, in the period between 2017 and 2019. The data was then used to calculate the arithmetic mean for all the fractions (MS Excel, R) and then using a proprietary web application, heatmaps were constructed. The obtained results showed significant differences in both the annual and daily variation of number concentrations between the individual fractions differing in particle size. In the case of the annual variation, one can see a greater variability of smaller particles, which is most likely due to the source of the actual suspended particles. Meteorological and dispersion conditions are found as important factors for suspended particle concentrations. These can lead to significant differences from year to year. However, a comparison between 2018 and 2019 showed that even though the average absolute number concentrations can differ between years, the actual relative number concentrations, i.e., the ratios between the individual fractions remain very similar. In conclusion it can be said that the difference between the number concentration variation of the size fractions depends on both the actual pollution sources (especially in the long-term, i.e., the annual variation) and the actual size of the particles, which plays a role especially in the short-term (daily, weekly variation).
- ItemVolatile organic compounds in motor vehicle interiors under various conditions and their effect on human health(Silesian University of Technology, Faculty of Transport and Aviation Engineering, 2020-05-17) Verner, Jan; Sejkorová, Marie; Veselík, PetrThe aim of this paper is to estimate the mass concentrations of volatile organic compounds (VOCs) such as benzene (B), toluene (T), ethylbenzene (E) and m-, p-, o-xylenes (X) inside of the driver-compartment of motor vehicles. The results were compared with the Czech limits for indoor environments and the external concentrations. The experiments were carried out on various routes with different methods of ventilation. The volatile emissions detected inside the vehicle were investigated in the city of Brno, Czech Republic. Cabin air was collected using desorption tubes and the samples were analysed by thermal desorption gas chromatography with a flame ionisation detector coupled with a mass detector. VOC concentrations detected in the cabin of the vehicle ranged from 2.93 mu g.m(-3) to 7.96 mu g.m(-3) for benzene, 1.42 mu s.m(-3) to 4.38 mu g.m(-3). for toluene, 44.06 mu g.m(-3) to 152.00 mu g.m(-3) for ethylbenzene and 63.07 mu g.m(-3) to 479.62 mu g.m(-3) for xylenes. The indoor limit value for benzene, according to the Czech standard, is 7 mu g.m(-3). Levels of toluene were consistently below the Czech hourly standard, whose value according to the Czech standard is 300 mu g.m(-3). According to our findings, various methods of ventilation are an important factor influencing the BTEX pollution levels within the interior of the vehicle. In addition, this paper presents the influence results of benzene on the health of passengers inside the cabin of the vehicle. The results show that all age categories, especially children under the age of two, are exposed to increased health risks.
- ItemCargo securing – comparison of the selected trucks(Silesian University of Technology, Faculty of Transport, 2020-12-08) Vlkovský, Martin; Veselík, PetrThe paper deals with a comparison of shocks (values of acceleration coefficients and inertial forces) of two types of vehicles (T-810 and T-815 MK IV) during transport experiments on a motorway. The measurement was performed using an OM-CP-ULTRASHOCK-5 three-axial accelerometer with a datalogger and calibration certificate. The goal of the paper is to accept or reject a hypothesis of the existence of a statistically significant difference between the values of the acceleration coefficients generated by the two vehicles. The statistical analysis of the measured data was done with use of two parameters. The results of the analysis show statistically significant differences between the examined vehicles. Based on the performed statistical analysis, the effect on cargo securing is demonstrated.