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The aim of this paper is a mathematical description of algorithm for controlled assembly of incinerated batch of waste. The basis for formation of batch is selected parameters of incinerated waste as its calorific value or content of pollutants or the combination of both. The numerical model will allow, based on selected criteria, to compile batch of wastes which continuously follows the previous batch, which is a prerequisite for optimized operation of incinerator. The model was prepared as for waste storage in containers, as well as for waste storage in continuously refilled boxes. The mathematical model was developed into the computer program and its functionality was verified either by practical measurements or by numerical simulations. The proposed model can be used in incinerators for hazardous and municipal waste.

Abstract Cytosolic Ca2+ and Na+ allosterically regulate Na+/Ca2+ exchanger (NCX) proteins to vary the NCX-mediated Ca2+ entry/exit rates in diverse cell types. To resolve the structure-based dynamic mechanisms underlying the ion-dependent allosteric regulation in mammalian NCXs, we analyze the apo, Ca2+, and Na+-bound species of the brain NCX1.4 variant using hydrogen-deuterium exchange mass spectrometry (HDX-MS) and molecular dynamics (MD) simulations. Ca2+ binding to the cytosolic regulatory domains (CBD1 and CBD2) rigidifies the intracellular regulatory loop (5L6) and promotes its interaction with the membrane domains. Either Na+ or Ca2+ stabilizes the intracellular portions of transmembrane helices TM3, TM4, TM9, TM10, and their connecting loops (3L4 and 9L10), thereby exposing previously unappreciated regulatory sites. Ca2+ or Na+ also rigidifies the palmitoylation domain (TMH2), and neighboring TM1/TM6 bundle, thereby uncovering a structural entity for modulating the ion transport rates. The present analysis provides new structure-dynamic clues underlying the regulatory diversity among tissue-specific NCX variants.

On the Slovak side of the Carpathian mountains, the archaeology of the First World War had long been completely outside the scope of research interest. At the same time, conflicts in this region had played a very important role in the initial phase of the war. Here, the Austro-Hungarian army blocked the invasion of the Russian army into Hungary with all its might. This lack of attention changed in the last decade with surveys conducted by our team from Masaryk University. In this short overview we describe and evaluate our main research conclusions so far based on surveys conducted at sites bearing the names of the hills of Staviská, Kobyla, Cingov and Wertyszów. Each of the sites is a place where various military events took place, so we have applied different, mostly non-destructive, methods to their study. Our results are mostly an introduction to the state of research and a review of a decade of expeditions to this unique field of conflict, where the armies learned how to fight in mountainous areas.

Valuation of the insurance portfolio is one of the essential actuarial tasks. Life insurance valuation is usually based on a projection of cash flows for each policy which is demanding computation time. Furthermore, modern financial management requires multiple valuations under different scenarios or input parameters. A method to reduce computation time while preserving as much accuracy as possible based on cluster analysisis p resented. The basic idea of the method is to replace the original portfolio by a smaller representative portfolio based on clusters with some weights that would ensure the similarity of the valuation results to the original portfolio. Valuation is then significantly faster but requires initial time for clustering and the results are only approximate – different from the original results. The difference is studied for a different number of clusters and the trade-off between the approximation error and calculation time is evaluated.

Polyvinyl chloride (PVC) is a petroleum-based plastic used in various applications, polluting the environment because of its recalcitrance, large content of additives, and the presence of halogen. In our case study, a new, two-stage biodegradation technology that combined composting process used for PVC pretreatment with a subsequent PVC attack by newly-isolated fungal and bacterial strains under SSF conditions was used for biodegradation of commercial PVC films. The novelty consisted in a combined effect of the two biodegradation processes and the use for augmentation of microbial strains isolated from plastic-polluted environments. First, the ability of the newly-isolated strains to deteriorate PVC was tested in individual, liquid-medium- and SSF cultures. Higher mass-reductions of PVC films were obtained in the former cultures, probably due to a better mass transfer in liquid phase. Using the two-stage biodegradation technology the highest cumulative mass-reductions of 29.3 and 33.2% of PVC films were obtained after 110 days with Trichoderma hamatum and Bacillus amyloliquefaciens applied in the second stage in the SSF culture, respectively. However, FTIR analysis showed that the mass-reductions obtained represented removal of significant amounts of additives but the PVC polymer chain was not degraded.

Distance learning and e-learning have significantly developed in recent years. It is also due to changing educational requirements, especially for adults. The article aims to show the advantages and disadvantages of distance learning. Examples of the 20-year use of the distance learning form of computer science describe the difficulties associated with the implementation and implementation of this form of teaching. The results of students in the full-time and distance form of teaching in the bachelor's study of computer science are compared. Long-term findings show that distant students have significantly lower scores in the first years of study than full-time bachelor students. In the following years of study, the differences diminish, and students' results are comparable. The article describes the possibilities of improving the quality of distance learning.

The importance of working with sufficiently robust methods has been rising in recent years. This growth is related to the extensive usage of highly frequent data, which we currently encounter in many fields including finance. Since with an increasing number of observations, the probability of outlier presence also rises. Moreover, as it is known, standard methods are not able to work correctly with outliers and, consequently, standard estimates are often biased. We focus on estimators of autocorrelation function for univariate time series, for which we propose a method based on clipping an original time series and working with a binary time series instead. The clipping helps to deal with outliers and the estimation is not affected as much as with standard methods. We also derive an asymptotical distribution of the estimator, what gives our method a major advantage in comparison with other robust methods, which are often presented without this. Furthermore, knowing the distribution of the estimator allows us to perform statistical inference.

An archaeological excavation in Prostějov (Czech Republic) revealed a workshop of a local potter with colourless, pink, and blue powders presumably used to produce faience/surface decoration. A comprehensive analytical study, which combined elemental and molecular analysis techniques, was performed to shed light on the chemical composition of these unique findings. Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM EDX), inductively coupled-plasma mass spectrometry (ICP MS), flow injection analysis (FIA) with electrospray ionisation mass spectrometry (ESI MS), laser desorption ionisation mass spectrometry (LDI MS), and Raman spectroscopy were applied to reveal the elemental composition of the powders and identify the colouring agents in the pink and blue powders. The colouring agents in the pink powder were probably iron and the agent in the blue powder is Prussian blue. On top of that, it was also possible to determine the organic additives in these powders through pyrolysis gas chromatography with mass spectrometric detection (Py GC/MS), atmospheric solids analysis probe ion mobility mass spectrometry (ASAP IM MS), and LDI MS. The organic constituents were identified as plant resin, beeswax, and fats. These results point to the preparation of faience/pigment mixtures as oil paint.

Roku 2016 byl v rámci řízené systematické detektorové prospekce zalesněného území západního Kroměřížska učiněn solitérní nález románského meče. Zbraň lze klasifikovat jako meč typu XII, B, 1, a její výrobu klást do průběhu 12. století. Čepel je tvořena ocelovým pláštěm obalujícím měkčí jádro, což byl v dané době poměrně nový typ konstrukce, a na obou jejích stranách byla zjištěna specifická cínem inkrustovaná iniciálová inskripce, kterou lze nejspíše číst jako Salvator Iesus Omnipotens Salvator, respektive Omnipotens Salvator Iesus Omnipotens. Tyto i další detaily nálezu jsou v článku podrobně diskutovány.

The main aim of our study is to show the influence of residual stresses on wear and surface ratcheting in the case of line rolling contact. Experiments were carried out on the innovated TUORS (Technical University of Ostrava Rolling Sliding testing machine) testing rig under free rolling and also under a slip ratio of 0,75 %. All specimens used for the experiments were made from R7T steel. A hole-drilling method and an X-ray diffraction method were applied to determine the residual stresses induced by repeated contact loading and technological residual stresses. Mazzu’s semi-analytical approach, which makes use of full integration of the Armstrong-Frederick model, was used to simulate ratcheting and wear. The proposed model calibration methodology, based on an inverse approach, allows the model parameters to be determined directly from the measured wear. The results of this study confirm that the observed technological compressive residual stresses lead to lower ratcheting and subsequently also to lower wear rates.

This paper presents an overview of extensive set fatigue tests results in low-cycle domain carried out at the Department of Applied Mechanics at the VŠB – Technical University of Ostrava on smooth specimens made of 2124T851 aluminum alloy. Overall, results of 24 tests of the aforementioned type under proportional loading and 40 tests under non-proportional loading with various strain path shapes were evaluated within the FADOFF project (Fatigue Analysis Documentation Office) supported by the Technology Agency of the Czech Republic. All tests were realized under the zero mean strain at the room temperature. Investigated aluminum alloy has exhibited in the torsion tests significantly shorter lifetime than under the tension-compression symmetrical loading at the same level of equivalent strain amplitude. The experimental set was realized in order to validate low-cycle fatigue criteria in a future work.

Background: Day-to-day walking variability appears not to be random and may fluctuate by day of week or type of day (workdays/non-workdays). The day-of-the-week variability is less clear in period of life transition between the ages of 50-70 years. Moreover, it is unclear whether the variability is related to age or BMI.Objective: The aim of this study was to identify the weekdays-weekends patterns and the day-to-day variability in step patterns in men and women of different age and BMI groups. Methods: During the years 2009-2012, 1,170 individuals (532 men and 638 women) aged 50-70 years participated in a seven-day monitoring using a Yamax Digiwalker SW-700 pedometer. Results: Using ANOVA of repeated measures, it was found that steps/day varied across the day of the week in both men and women in younger age groups (≤ 64 years) (p ≤ .04), whereas in older age group (65-70 years), no significant systematic variability by day of the week was found. Existence of variability by day of the week with significant drop in steps/day on weekend days, especially on Sunday, was confirmed in normal weight, overweight and obese Czech men and women. Conclusion: In conclusion, this study contributes to the evidence with the findings about the existing the day-of-the-week variability of step counts per day in the population aged 50 to 64 years and about the absence of significant variability in seniors (≥ 65 years). Sunday was the least active day in different age and BMI groups aged 50 to 70 years of Czech population. Researchers and practitioners should take the results of this study into consideration when preparing for data collection of habitual physical activity in senior population and in the development of walking interventions and weight reduction programmes designed for this age group.

In case of expected horizontal deformation of subsoil or foundation structure it is possible to use rheological asphalt sliding joint to eliminate internal forces caused with friction. Material characteristics of asphalt are temperature sensitive. In science literature it is possible to find data with temperatures expected in footing bottom, however it was decided to complement this information with temperatures measured in-situ in foundation slab for super-computer building in campus of VŠB-Technical University of Ostrava. In the paper measured and calculated temperatures are compared for the first days after concreting the foundation structure. Besides the temperature of environment also significant influence of heat of cement hydration are taken into account.

This article is devoted to an analysis of scalar, vector and tensor fields, which occur in the loaded and deformed bodies. The aim of this article is to clarify and simplify the creation of an understandable idea of some elementary concepts and quantities in field theories, such as, for example equiscalar levels, scalar field gradient, Hamilton operator, divergence, rotation and gradient of vector or tensor and others. Applications of those mathematical terms are shown in simple elasticity and plasticity tasks. We hope that content of our article might help technicians to make their studies of necessary mathematical chapters of vector and tensor analysis and field theories easier.

The paper describes the experimental results obtained for the combined loading of the specimens in the region of high-cycle fatigue. The specimens were manufactured from common structural steel 11523.1. There has been realized a set of proportional and non-proportional experiments in the area of high-cycle fatigue for basic methods of loading, namely: tension/compression, bending and torsion and its mutual combinations. By selected experiments, the specimens were additionally loaded by constant inner/outer pressure and axial prestress for a various loading levels. Experiments were realized on testing machines, situated at author´s workplace. The experimental results were undergone to application of selected and known criteria of fatigue strength and subsequently carried out its modification according to the results. For gaining necessary input values for criteria of fatigue strength, there was a need to realize a FEM simulation of test specimens.

In this study, a soil from two ceramic vessels belonging to Corded Ware culture, 2707⁻2571 B.C., found in a cremation grave discovered in Central Moravia, Czech Republic, was analyzed using matrix-assisted laser desorption/ionization⁻mass spectrometry (MALDI⁻MS) combined with advanced statistical treatment (principal component analysis, PCA, and orthogonal projection to latent structures discriminant analysis, OPLS-DA) and by enzyme-linked immunosorbent assay (ELISA). MALDI⁻MS revealed the presence of triacylglycerols in both vessels. This analytical technique was used for the analysis of the soil content from archaeological ceramic vessels for the first time. Targeted ELISA experiments consequently proved the presence of milk proteins in both ceramic vessels. These results represent the first direct evidence of the use of milk or dairy products in the Eneolithic period in Moravian Corded Ware Culture and help to better understand the diet habits and living conditions of Eneolithic populations in Central Europe.

Modelling the temperature field of a continuously cast strand is an important tool for the process diagnostics. The main preconditions for numerical simulation of the temperature field of the solidifying strand are correct boundary conditions, especially the surface condition in the secondary zone of the caster. The paper deals with techniques of determining the surface condition under cooling nozzles as well as their approximation and implementation into the model algorithm. Techniques used for laboratory measurements of both cold and hot spraying characteristics of water or water-air cooling nozzles are described. The relationship between the cold and hot characteristics was found. Implementation of such a dependence into the model algorithm reduces the duration and cost of laboratory measurements.

Presented paper deals with ratcheting prediction in the field of contact fatigue for the case of line contact. For the stated purposes, the wear model proposed by A. Mazzu [1] is used, which stands out for its simplicity and time efficiency. The model is based on non-linear kinematic and isotropic hardening rule of Chaboche and Lemaitre. Mazzu´s approach is used in order to estimate the wear of wheel specimen as well as plastic shear strain accumulation in case of rolling/sliding contact after cycles in range from 4.10^5 to 1.10^6. Obtained results are compared with experimental data, available on author´s department.

BACKGROUND: International studies associate physical activity (PA) to other factors such as the environment, culture, and policy. External influences on lifestyle and PA, such as the effect of the physical and built environment, are discussed. Neighborhood environments seem to be one of the important aspects in prevention of unhealthy lifestyle and physical inactivity research. OBJECTIVE: The main objective is to analyze the relationship between PA and neighborhood environment of the adult population of the Czech Republic. The study tries to define the basic correlates of PA in relation to environmental and other socio-demographic factors. METHODS: Nationwide data collection of adult PA was done regionally in the Czech Republic between the years 2005–2009 using the IPAQ (long) and ANEWS questionnaires. RESULTS: The results show that males realize significantly more vigorous PA than females while females realize more moderate PA and walking than males. PA of residents of smaller communities is higher than those living in large cities. The level of weekly PA does not significantly affect the neighborhood walkability [H(3, 8708) = 19.60; p < .001; η2 = .002]. CONCLUSIONS: The results clearly indicate the need to connect multiple sectors that affect the lifestyle of the general population. Possible solution is an interdisciplinary approach to the evaluation of the fundamental environmental factors influencing the level of PA (walkability; SES; participation in organized and voluntary PA; neighborhood safety; type of transportation; size of the community).

The paper deals with research of the heat transfer in the mould of continuous casting and the thermal boundary condition determination using combination of measurement and the inverse technique of numerical simulation. An average heat flux in the mould is calculated from measured parameters of mould cooling water. Layout of the heat flux at the mould working surface is derived by the original experimental and numerical simulation procedure, which is based on measuring temperatures in the mould walls and solving a numerical inverse problem including stress and shrinkage, using the software package Procast. A database of the heat flux layouts was built for various values of casting speed and steel chemical composition for purpose of determination the boundary condition for on-line modeling.

BACKGROUND: Regular physical activity is an important factor in human health status. The fact, that the physical activity will be regular, is influenced by many internal and external individual factors. Education is considered to be an important factor that influences physical activity. There has not been fully clarified the relationship between physical activity and education in pursuit of regional indicators yet. AIM: The aim of this study was to analyze the physical activity of adult inhabitants of the Moravian-Silesian region with regard to the number of years spent in formal education. METHODS: The research sample consisted of 759 residents of MoravianSilesian region (419 women and 340 men) aged 25-58. The IPAQ questionnaire was used to obtain the data, which was distributed by trained university students in the spring and autumn periods of 2005-2009. Kruskal Wallis ANOVA test was used for the statistical evaluation of the data. The effect size was calculated to clarify the internal differences in results. RESULTS: Significant differences in the structure of physical activity were found only in men in the job related physical activity (H = 6.277; p = 0.05; η2 = 0.019) and in vigorous physical activity (H = 6.230; p = 0.05; η2 = 0.018). Physically most active are men with lowest level of education. No significant difference was found in the monitored parameters for women. Job related physical activity means the highest part of the total physical activity in respondents with lowest education. CONCLUSION: The results of the survey point to the fact, that different level of education is not an important factor associated with physical activity in Moravian-Silesian region. To promote physical activity we would recommend focusing on physical activity in leisure time, during transport and on vigorous physical activity in all groups of respondents based on educational level.

The paper describes the experimental results obtained for the combined loading of the specimens in the region of high-cycle fatigue. The specimens were manufactured from common structural steel 11523.1, melt T31052. The following experiments were performed: The first set of the specimens was loaded by the alternating torque amplitude. The second set was loaded by the in fully reversed push-pull. The third set of specimens was loaded by the combination of the torque and of the fully reversed push-pull. The phase shift is zero in this experiment. The results were evaluated by the modified conjugated strength criterion and other generally used multiaxial fatigue criteria. The stress-strain analysis of the specimens by FEM was performed to determine parameters (constants) of particular strength criteria.

BACKGROUND: Optimal physical activity (PA) is next to balanced healthy diet and medical care one of the key determinants of prevention of overweight and obesity. Although the Czech Republic is still considered "walkable" society, the increase of obesity initiated the search for bio-psycho-social determinants and correlates of health enhancing PA not only on the national but also on the regional level. Environmental and economical conditions in individual regions in the Czech Republic can stimulate or inhibit regular PA in their inhabitants. AIM: The aim of the study was to identify bio, psycho, social and environmental correlates of health enhancing physical activity in adults in Ostrava region using the analysis of data from the ANEWS questionnaire applied in 2005-2009. METHODS: In order to estimate the level of weekly PA, data of a random sample of 820 inhabitants of Ostrava region were used (448 women and 372 men) aged 40.65 ± 8.75. The ANEWS questionnaire was applied in 2005-2009. Health enhancing PA means minimum of 30 minutes of moderate PA 5 times a week, or 20 minutes of intense PA 3 times a week. The statistical evaluation was supported by Formal concept analysis. RESULTS: Men and women with a paid job and active transport, or low sitting (≤ 4 hours daily) or highly intensive PA (≥ 6 METs) are more likely (≥ 10 %) to carry out health enhancing PA than women and men without a paid job or passive transport, or with high sitting (> 4 hours a day) or without intensive PA. Age, weight, smoking, participation in organized forms of PA, season, and the size of location are not significant correlates of health enhancing PA in the inhabitants of Ostrava region. CONCLUSION: The support of employment, active transport and maintenance of "walking" and "cycling" environment in Ostrava region supports also health enhancing PA.

Cílem této studie je analyzovat demografi cké faktory vztahující se k intenzivní a středně zatěžující pohybové aktivitě, chůzi a času stráveným sezením u obyvatel České republiky ve věku 55–69 let a výsledky výzkumu využít jako podklady pro Ministerstvo zdravotnictví při řešení problematiky zdraví a tím přispět ke zkvalitnění životního stylu u této populace. 320 systematicky náhodně vybraných obyvatel České republiky ve věku 55–69 se zúčastnilo této studie. Pro zjištění pohybové aktivity a času stráveného sezením byla aplikována standardizovaná administrativní dlouhá verze mezinárodního dotazníku "International Physical Activity Questionnaire". V rámci doplňkové verze dotazníku respondenti poskytli demografické údaje. Pro zjištění vlivu demografi ckých faktorů na pohybovou aktivitu a inaktivitu byla využita binární logistická regrese v programu SPSS 16.0. Doporučení pro intenzivní pohybovou aktivitu splnilo pouze 20,3 % respondentů, pro středně zatěžující pohybovou aktivitu 52,5 % respondentů a pro chůzi 54,4 % respondentů. Z výsledků logistické regrese vyplývá, že větší šanci splnit doporučení pro chůzi mají zaměstnaní lidé a větší šanci splnit doporučení k středně zatěžující pohybové aktivitě mají respondenti ve věku 55–59 let, nekuřáci, se základním vzděláním a žijící v rodinném domku. S rostoucím věkem se zvyšoval i čas strávený sezením. [The aim of this study is to examine weekly physical activity and sitting and to investigate the relationship between socio-demographic and environmental factors and physical activity of the inhabitants of the Czech Republic aged 55–69. 320 persons (173 male and 147 female) aged 55–69 from all 14 regions of the Czech Republic participated in this study. The self administrative version of "International Physical Activity Questionnaire" IPAQ was used to assess physical activity levels. Participants provided socio-demographic and environmental information. From the total sample, only 20.3% of respondents met the guidelines for vigorous physical activity. 52.5% of respondents accomplished the recommended minimum for moderate physical activity and 54.4% of respondents met the recommended values for walking. Binary logistic regression analyses showed that employed people were more likely to meet the weekly guidelines for walking. 55–59 years old respondents (compared to 65–69 years old), non smokers, completed elementary education (compared to people completed secondary and university education), and lived in house were more likely to be moderately active. Persons aged 65–69 were more likely to spend sitting more than 300 minutes a day compared to respondents aged 55–59.]

The Integrated Portal of the Ministry of Labour and Social Affairs of the Czech Republic provides the unemployed the possibility to find appropriate vacancy according to various criteria. The possibility of public transport connection existence between municipality of residence and municipality of potential vacancy is one of many various criteria of searching. Data for this option are guaranteed by VSB-TU of Ostrava. Valid time tables are used as information source of public transport connection existence and manual or automatical processing can be used for data mining. Due to the fact, that about 13.5 million of connections are calculated, it has to be used automatical processing. This paper describes the software solution, where the whole process is automatically distributed to many powerful workstations for parallel processing of all public transport connection combinations.

The paper deals with design of the computer system for measurements of the phase shift between two harmonic signals using the Digital Signal Processor (DSP). The introducing part of the paper describes properties of the harmonic signals and the Hilbert transform. Concerning the Hilbert transform their two methods for computing, one is based on the Fourier transform while the second one benefits from the digital filters. The submitted paper deals with mentioned two methods for the phase evaluation as well. The phase shift between two harmonics signals is useful for rotors balancing. The algorithm of rotor balancing requires the amplitude of both the signals as well.