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Repositories for radioactive wastes are sited in the environment with very low permeability. One of the most important processes leading to the release of radionuclides to the environment is therefore diffusion of radionuclides in both natural and engineered barriers. Data for its description are crucial for the results of safety assessment of these repositories. They are obtained usually by comparison of the results of laboratory diffusion experiments with analytical and/or numerical solution of the diffusion equation with specified initial and boundary conditions. Results of the through-diffusion experiments are obviously evaluated by the “time-lag” method that needs for most of sorbing species unfortunately very long time of the experiment duration. In this paper a modified approach is proposed for the evaluation of diffusion data for safety assessment, which decreases the influence of propagation uncertainties using incorrect data and reduces time for acquiring data for safety assessment. This approach consist in the following steps: (i) experimental measurement of material diffusion parameters under various conditions using non-sorbing tritiated water or chlorine for which it is easy to reach conditions under which the “time-lag” method of evaluation of the result of the through-diffusion experiment is applicable—this step provides well established diffusion characteristics of materials for neutral species and anions, then (ii) to evaluate sorption isotherms for sorbing radionuclides from batch experiments under conditions corresponding to composition of material pore water, (iii) to assess the values of effective and apparent diffusion coefficients for sorbing radionuclides from well-defined diffusion coefficients of species in free water and (iv) to verify the obtained results using relatively short-term diffusion experiments with sorbing radionuclides, which will be evaluated using the time dependent decrease of the concentration in the input reservoir of the diffusion cell. A numerical model of the diffusion cell can model the decrease of concentration of species. The code, which we used for this type of evaluation of diffusion experiment, is based on the same approach to modelling that we use for modelling of the diffusion transport in performance assessment studies. The advantage of this approach consists in the compatibility of the approaches used for both evaluation and verification of the laboratory diffusion experiments and performance assessments and in considerable less time needed for experiments.

This article deals with the assessment of methodologies for water vapor condensation determination and mold growth risk analysis on the surfaces of an organic building structure based on in-situ monitoring, carried out on the structural elements of renovated roof truss above the greenhouse “Květná zahrada” in Kroměříž. The garden including the building is signed on the UNESCO Word Heritage List for its historical and architectonical value. The monitoring was focused on hygrothermal behavior of a particular attic area during winter term 2014 - 2015. The risks of water vapor condensation and mold growth were then analyzed on the basis of data obtained by the monitoring process. These also include measurement and output data accuracy is included as well. The Results were used as recommendation for a control system of forced ventilation in the monitored attic area.

Safety and efficiency are commonly regarded as two significant performance indicators of transportation systems. In practice, road network planning has focused on road capacity and transport efficiency whereas the safety level of a road network has received little attention in the planning stage. This study develops a Bayesian hierarchical joint model for road network safety evaluation to help planners take traffic safety into account when planning a road network. The proposed model establishes relationships between road network risk and micro-level variables related to road entities and traffic volume, as well as socioeconomic, trip generation and network density variables at macro level which are generally used for long term transportation plans. In addition, network spatial correlation between intersections and their connected road segments is also considered in the model. A road network is elaborately selected in order to compare the proposed hierarchical joint model with a previous joint model and a negative binomial model. According to the results of the model comparison, the hierarchical joint model outperforms the joint model and negative binomial model in terms of the goodness-of-fit and predictive performance, which indicates the reasonableness of considering the hierarchical data structure in crash prediction and analysis. Moreover, both random effects at the TAZ level and the spatial correlation between intersections and their adjacent segments are found to be significant, supporting the employment of the hierarchical joint model as an alternative in road-network-level safety modeling as well.

Owing to their large saturation magnetization and low hysteresis loss, soft magnetic layers based on amorphous alloys currently receive great attention for their potential for gigahertz frequencies applications. In this paper, we studied the structural and magnetic properties of amorphous FeCoB/AlN multilayered thin films with in-plane uniaxial magnetic anisotropy based on the Fe-28%Co-20%B (at. %) alloy, deposited on 8” Si/200 nm-thermal-SiO2 wafers in an industrial, high-throughput magnetron sputtering system. Depending on the process conditions and hardware configuration, the multilayers exhibit structural anisotropy consisting of surface ripples elongated perpendicular to the incident flux direction, which replicate through the entire multilayer stack. By varying the AlN interlayer thickness and sputter process parameters the anisotropy field $H_{k}$ of these films was tuned in the range of 25–130 Oe, while the coercivity along the magnetic easy axis $H_{c}$ was kept low, 0.2–0.3 Oe. The ferromagnetic resonance frequency of the multilayered structures was ~2 GHz, and the experimental behavior of the magnetization dynamics was described by the classical Landau–Lifschitz–Gilbert model. Magnetic domain imaging confirmed a strong coupling between the adjacent FeCoB layers, in agreement with the edge-curling wall model.

Abstract Multi-criteria decision-making (MCDM) methods are very useful tools for daily decision-making in different fields. In addition, determining an acceptable solution with respect to different factors is certainly a very demanding and difficult task. In this paper, a new Measurement of Alternatives and Ranking according to COmpromise Solution (MARCOS) method for a sustainable supplier selection in the healthcare industry (in a polyclinic) in Bosnia and Herzegovina is developed. The advantages of the developed method are: the consideration of an anti-ideal and ideal solution at the very beginning of the formation of an initial matrix, closer determination of utility degree in relation to both solutions, the proposal of a new way to determine utility functions and their aggregation, the possibility to consider a large set of criteria and alternatives while maintaining the stability of the method. Supplier selection is very important for organizations in the medical industry. Sustainability in the supplier selection process in the medical industry is a strategically important issue, and poorly implemented in the private medical sector. Therefore, the example explains how to use the MARCOS method to select sustainable suppliers in the private medical sector. A case study of a sustainable supplier selection for the healthcare industry (a polyclinic) includes ranking of eight alternatives with regard to 21 criteria for all aspects of sustainability. The results and verification of the new method are carried out throughout a comprehensive sensitivity analysis. 21 scenarios with changes in the weight values of criteria were established, the measurement scale from 1 to 9 was changed to 1–5, a comparison with six other MCDM methods was performed, and it was verified in dynamic conditions which implied a change of the elements of the initial decision-making matrix. All phases of the sensitivity analysis showed the validity of MARCOS method. The obtained results and all scenarios in sensitivity analysis show that A2 remains the best alternative.

Abstract The aim of the paper is to study the validation and correction of the Convective Rainfall Rate (CRR) algorithm, which utilises three channels from Meteosat Second Generation to estimate rainfalls: IR 10.8 μm, WV 6.2 μm and VIS 0.6 μm. The original CRR algorithm was applied to data from Central Europe (the Czech Republic) but since the calibration matrices (which are the core of CRR) were previously derived using data from Spain and Norway, we recalculated these matrices using data from the Czech Republic. We found that the original and the new matrices were significantly different in absolute values and in the values of IR 10.8 μm, WV 6.2 μm and VIS 0.6 μm under which rainfalls were observed. We subjectively modified these calculated calibration matrices and used them within the CRR algorithm. We also complemented the algorithm with the correction of the distribution of estimated rainfalls. All three methods, the original and our two algorithms, were compared according to various categorical measures and other statistical measures (like Root Mean Square Error). The results showed that the new calibration matrices, complemented by the distribution correction, yielded more accurate rainfall estimates than the other two methods.

We report on results of a passive seismic experiment undertaken to study the 3-D velocity structure and anisotropy of the upper mantle around the contact zone of the Saxothuringicum and Moldanubicum in the western margin of the Bohemian Massif in central Europe. Spatial variations of P-wave velocities and lateral variations of the particle motion of split shear waves over the region monitor changes of structure and anisotropy within the deep lithosphere and the asthenosphere. A joint interpretation of P-residual spheres and shear-wave splitting results in an anisotropic model of the lithosphere with high velocities plunging divergently from the contact of both tectonic units. Lateral variations of the mean residuals are related to a southward thickening of the lithosphere beneath the Moldanubicum.

Almost all reinforced concrete structures which are exposed to weather effects are threatened by corrosion. The corrosion of steel elements in structures has an influence on lifetime these constructions and adversely affects their properties. However, the steel in concrete structures is protected against corrosion due to the properties of concrete such as high pH or impermeability, but if the concrete is of poor quality and his protective properties are insufficient the corrosion can occur. A problem causes the action of carbon dioxide which has the effect of lowering the pH below the critical value and thereby accelerating the corrosion.Non-destructive methods such as Impact-echo method offer the possibility of easy and quickly detection of initial damage of structure and thus can prevent the occurrence of permanent damage to the whole construction.This article describes the development of corrosion which is caused by carbonation of the concrete and supported by action of chlorides by using Impact-echo method. The paper presents results obtained on the reinforced concrete samples with one steel rod passing through the center. After carbonation concrete the samples were exposed accelerated controlled degradation in aqueous NaCl solution for 4 months.

Abstract Diffuse pollution from agricultural drainage is a severe problem for water quality and it is a major reason for the failure to accomplish “good chemical status of surface waters” according to the Water Framework Directive and for the eutrophication of both freshwaters and coastal waters. Constructed wetlands were proposed as a suitable tool for removal of nitrogen from agricultural drainage in the early 1990s. Until now, the vast majority of constructed wetlands designed to treat tile drainage were free-surface constructed wetlands. In 2018, three experimental constructed wetlands with horizontal subsurface flow were built to treat tile drainage from 15.73 ha watershed. The wetlands have a surface area of 79, 90 and 98 m2 and were planted with Phalaris arundinacea and Glyceria maxima in parallel bands. The substrate in the first two wetlands is gravel (4–8 mm) mixed with birch woodchips (10: 1 volume ratio). In one of those wetlands, the water level is kept 10 cm above the surface, in the second one the water is kept below the surface. The third wetland has 20 cm layer of birch woodchips on top of gravel. The mean total nitrogen concentration eliminations during one-year period were 61.2%, 62.6% and 70.9% for wetlands 1, 2 and 3, respectively. The average load removals amounted to 0.516, 0.323 and 0.399 g N m−2 d−1 or 1885, 1180 and 1457 kg ha−1 yr−1 in wetlands 1, 2 and 3 respectively. The plant uptake and nitrogen sequestration in aboveground biomass contributed only marginally to the overall nitrogen removal. The results revealed that the selection of the best option depends on the fact whether concentration or load is taken as the most important parameter.