The problem of estimation of the long-term environmental noise hazard indicators and their uncertainty is presented in the present paper. The type A standard uncertainty is defined by the standard deviation of the mean. The rules given in the ISO/IEC Guide 98 are used in the calculations. It is usually determined by means of the classic variance estimators, under the following assumptions: the normality of measurements results, adequate sample size, lack of correlation between elements of the sample and observation equivalence. However, such assumptions in relation to the acoustic measurements are rather questionable. This is the reason why the authors indicated the necessity of implementation of non-classical statistical solutions. An estimation idea of seeking density function of long-term noise indicators distribution by the kernel density estimation, bootstrap method and Bayesian inference have been formulated. These methods do not generate limitations for form and properties of analyzed statistics. The theoretical basis of the proposed methods is presented in this paper as well as an example of calculation process of expected value and variance of long-term noise indicators LDEN and LN. The illustration of indicated solutions and their usefulness analysis were constant due to monitoring results of traffic noise recorded in Cracow, Poland.
The paper presents the core design, model development and results of the neutron transport simulations of the large Pressurized Water Reactor based on the AP1000 design. The SERPENT2.1.29 Monte Carlo reactor physics computer code with ENDF/BVII and JEFF 3.1.1 nuclear data libraries was applied. The full-core 3D models were developed according to the available Design Control Documentation and the literature. Criticality simulations were performed for the core at the Beginning of Life state for Cold Shutdown, Hot Zero Power and Full Power conditions. Selected core parameters were investigated and compared with the design data: effective multiplication factors, boron concentrations, control rod worth, reactivity coefficients and radial power distributions. Acceptable agreement between design data and simulations was obtained, confirming the validity of the model and applied methodology.
Introduction: Interventional cardiology (IC) is a rapidly expanding fi eld of medicine. Medical studies should provide students the necessary level of knowledge about new techniques in IC. The aim of the study was to assess the medical students’ knowledge about various new areas of IC. Material and methods: Self-designed questionnaire was used to assess student’s knowledge. It contained 31 questions. Th e initial 3 questions concerned general information, the remaining ones were related to diff erent IC techniques: Transcatheter Aortic Valve Implantation (TAVI), Bioresorbable Vascular Scaff old (BVS), percutaneous mitral regurgitation repair methods, Left Atrial Appendage Occlusion (LAAO), Renal DeNervation (RDN), Balloon Aortic Valvuloplasty (BAV) and Atrial Septal Defect/Persistent Foramen Ovale (ASD/PFO). One point for each correct answer was awarded. Results: In our study participated 104 students. Mean score was 15.9 ± 5.8 points. 24% of participants were 3rd year students, 38% — 4th, 20% — 5th and 18% — 6th. Th ere was no diff erences in level of knowledge between students of diff erent years of studies (p = 0.2). Students from Students Research Groups (SRG) achieved higher score in comparison with students no attending SRG (19.3 ± 6.3 vs 13.3 ± 3.7; p <0.001) as well as students interested in cardiology comparison with other (19.6 ± 5.9 vs 13.0 ± 3.8; p <0.001). Students from SRG and interested in cardiology reached also higher results in practically every area of IC in comparison with other. Conclusions: Participants have insuffi cient, outdated and incomplete knowledge of new methods in IC. Th ere was no signifi cant diff erence in students of diff erent years of studies. Students belonging to cardiological SRG and interested in cardiology have greater knowledge in IC.