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  • Author: Lenka Kovačiková x
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Abstract

The submitted article focuses on a detailed explanation of the average and range method (Automotive Industry Action Group, Measurement System Analysis approach) and of the honest Gauge Repeatability and Reproducibility method (Evaluating the Measurement Process approach). The measured data (thickness of plastic parts) were evaluated by both methods and their results were compared on the basis of numerical evaluation. Both methods were additionally compared and their advantages and disadvantages were discussed. One difference between both methods is the calculation of variation components. The AIAG method calculates the variation components based on standard deviation (then a sum of variation components does not give 100 %) and the honest GRR study calculates the variation components based on variance, where the sum of all variation components (part to part variation, EV & AV) gives the total variation of 100 %. Acceptance of both methods among the professional society, future use, and acceptance by manufacturing industry were also discussed. Nowadays, the AIAG is the leading method in the industry.

Abstract

Archaeological research in the area of the chateau park uncovered the relic of the Gothic church of St. Elisabeth, dated to the second half of the 13th century. It is a single-nave building with a rectangular finish (length 25 m, boat width 13 m, presbytery width 10.5 m). The church probably had an older predecessor - a wooden structure on a stone foundation, dating from the mid-13th century. At the same time, the church site was a burial place: a grave of a young woman and a 1.5-year-old child, dated 13th/14th century were found outside the presbytery wall. In the presbytery, there were 3 graves of men dating back to the 14th century. It is very likely that these are the Lords of the Wallenstein family. Archaeological research in graves in the Church of St. Elisabeth unearthed a small collection of animal bone remains. The occurrence of bones of young and mature cattle and domestic fowls, which are abundant in the archaeozoological assemblage, indicates the prevailing meat consumption of these animals. The butchering marks on their bones document removal of meat from the carcasses.

Abstract

The molecular dynamics simulations of the liquid-vapor equilibrium of water including both water phases — liquid and vapor — in one simulation are presented. Such approach is preferred if equilibrium curve data are to be collected instead of the two distinct simulations for each phase separately. Then the liquid phase is not restricted, e.g. by insufficient volume resulting in too high pressures, and can spread into its natural volume ruled by chosen force field and by the contact with vapor phase as vaporized molecules are colliding with phase interface. Averaged strongly fluctuating virial pressure values gave untrustworthy or even unreal results, so need for an alternative method arisen. The idea was inspired with the presence of vapor phase and by previous experiences in gaseous phase simulations with small fluctuations of pressure, almost matching the ideal gas value. In presented simulations, the first idea how to calculate pressure only from the vapor phase part of simulation box were applied. This resulted into very simple method based only on averaging molecules count in the vapor phase subspace of known volume. Such simple approach provided more reliable pressure estimation than statistical output of the simulation program. Contrary, also drawbacks are present in longer initial thermostatization time or more laborious estimation of the vaporization heat. What more, such heat of vaporization suffers with border effect inaccuracy slowly decreasing with the thickness of liquid phase. For more efficient and more accurate vaporization heat estimation the two distinct simulations for each phase separately should be preferred.