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In this paper measuring and determining of initial geometrical imperfections of set of glass members are presented. Measured specimens had the different dimensions and different composition – monolithic glass or laminated glass using different types of interlayer foils and glass panes. The shape of initial overall bow was measured using different methods and results were statistically evaluated and compared with allowable values defined in standards.

In most parts of the electromagnetic spectrum, solar radiation cannot penetrate clouds. Therefore, cloud detection and masking are essential in image preprocessing for observing the Earth and analyzing its properties. Because clouds vary in size, shape, and structure, an accurate algorithm is required for removing them from the area of interest. This task is usually more challenging over bright surfaces such as exposed sunny deserts or snow than over water bodies or vegetated surfaces. The overarching goal of the current study is to explore and compare the performance of three Convolutional Neural Network architectures (U-Net, SegNet, and DeepLab) for detecting clouds in the VEN μ S satellite images. To fulfil this goal, three VEN μ S tiles in Israel were selected. The tiles represent different land-use and cover categories, including vegetated, urban, agricultural, and arid areas, as well as water bodies, with a special focus on bright desert surfaces. Additionally, the study examines the effect of various channel inputs, exploring possibilities of broader usage of these architectures for different data sources. It was found that among the tested architectures, U-Net performs the best in most settings. Its results on a simple RGB-based dataset indicate its potential value for any satellite system screening, at least in the visible spectrum. It is concluded that all of the tested architectures outperform the current VEN μ S cloud-masking algorithm by lowering the false positive detection ratio by tens of percents, and should be considered an alternative by any user dealing with cloud-corrupted scenes. [ABSTRACT FROM AUTHOR]

Air pollution is currently considered one of the most serious problems facing humans. Fine particulate matter with a diameter smaller than 2.5 micrometres (PM2.5) is a very harmful air pollutant that is linked with many diseases. In this study, we created a machine learning-based scheme to estimate PM2.5 using various open data such as satellite remote sensing, meteorological data, and land variables to increase the limited spatial coverage provided by ground-monitors. A space-time extremely randomised trees model was used to estimate PM2.5 concentrations over Europe, this model achieved good results with an out-of-sample cross-validated R2 of 0.69, RMSE of 5 μg/m3, and MAE of 3.3 μg/m3. The outcome of this study is a daily full coverage PM2.5 dataset with 1 km spatial resolution for the three-year period of 2018–2020. We found that air quality improved throughout the study period over all countries in Europe. In addition, we compared PM2.5 levels during the COVID-19 lockdown during the months March–June with the average of the previous 4 months and the following 4 months. We found that this lockdown had a positive effect on air quality in most parts of the study area except for the United Kingdom, Ireland, north of France, and south of Italy. This is the first study that depends only on open data and covers the whole of Europe with high spatial and temporal resolutions. The reconstructed dataset will be published under free and open license and can be used in future air quality studies. [ABSTRACT FROM AUTHOR]

The use of in situ references in Earth observation monitoring is a fundamental need. LUCAS (Land Use and Coverage Area frame Survey) is an activity that has performed repeated in situ surveys over Europe every three years since 2006. The dataset is unique in many aspects; however it is currently not available through a standardized interface, machine-to-machine. Moreover, the evolution of the surveys limits the performance of change analysis using the dataset. Our objective was to develop an open-source system to fill these gaps. This paper presents a developed system solution for the LUCAS in situ data harmonization and distribution. We have designed a multi-layer client-server system that may be integrated into end-to-end workflows. It provides data through an OGC (Open Geospatial Consortium) compliant interface. Moreover, a geospatial user may integrate the data through a Python API (Application Programming Interface) to ease the use in workflows with spatial, temporal, attribute, and thematic filters. Furthermore, we have implemented a QGIS plugin to retrieve the spatial and temporal subsets of the data interactively. In addition, the Python API includes methods for managing thematic information. The system provides enhanced functionality which is demonstrated in two use cases. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of analysis of beams made of SCP (sandwich composite panel) composed of GFRP face sheets and foam core. In the frame of research project, several specimens of different compositions were tested by four-point bending according to the actual standard. Nonlinear behaviour was observed in some specimens and possible reasons are discussed in the paper. SCP beams were also numerically simulated using the finite element method in ANSYS Workbench software. For practical and easy engineering design (prediction of deformations and stresses) the analytical procedure was developed for linear and nonlinear behaviour. Results represented by P-Δ and P-σ diagrams of experimental, numerical, and theoretical analysis are compared together in this paper. Based on the analytical solution the parametric study was performed to find out the optimal composition of SCP members for specific static boundary conditions. [ABSTRACT FROM AUTHOR]

Steel members of double-symmetrical open cross-sections are often used in engineering structures and structures of buildings as columns and beams. Due to connections of the members, transverse compression of the cross-section webs can occur and is subject to structural assessment. The resistance of the column web is influenced by structural solution of the joint (welded, bolted, with end plates) and possible interaction with axial force in the column or shear. The paper focuses on numerical investigation and quantification of the influence of axial force in the column on behaviour and resistance of the column web in transverse compression. The analysis was performed using finite element method based computation system and included both rolled and welded cross-sections with various values of relative slenderness of the web. The results were compared with results of transverse compression resistance calculated using actual standard for design of steel structures. [ABSTRACT FROM AUTHOR]

In recent architecture glass is widely used structural material of facades, walls, roof, stairs and other applications. Glass as a material is popular for its transparency, but it need to be carefully analysed for its fracture behaviour. This paper deals with some aspects of numerical modelling and designing of all-glass railings acting as cantilever element fixed at the bottom edge and with a handrail on the top edge. In the frame of study, number of different glass railings models were analysed to find out the best way how to simulate glass railing imposed to the impact load. The impact load is in most cases decisive load case acting on that type of structure. Variable parameters entering the analysis are the aspect ratio of glass railing pane, impact intensity, impact member hardness and finite element meshing. Finite element analysis of 250 models was performed in ANSYS Workbench. [ABSTRACT FROM AUTHOR]

The study defines the categorial framework for the analysis of so-called dislocated structures in contrastive perspective. First, it describes the systemic possibilities of the French and Czech syntaxes in relation to the phenomena studied. The syntactical potential is assessed from a functional point of view, making it possible to explain differences in the use of systemically possible structures in the two languages. The evaluation of systemic possibilities is complemented by a parallel corpus analysis performed in the InterCorp corpus. The study does not include all cases classified as dislocation (extraposition) in the specialized literature, as it focuses primarily on the left-hand extraposition of selected valency verb complements. [ABSTRACT FROM AUTHOR]

Copyright of Etudes Romanes de Brno is the property of Masaryk University, Faculty of Arts and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glued laminated timber (glulam), as one of the types of engineered wood products, is in our conditions most often made of coniferous, specifically spruce wood. In order to find optimal usage of material, some new configurations of cross-sections are being suggested. An advanced solution of glulam cross-section could be represented by cross-section formed from combination of hardwood (from deciduous trees) and softwood (from conifers). This paper deals with a possibility of combination of outer lamellas from a hardwood and inner lamellas from a softwood in glulam cross-section. The solution is focused on members suitable for a use in a skeleton frame. Attention is paid to two types of structural members: beam and column. Results of theoretical study are presented which arise from an analytical calculation and from a numerical modelling. For comparison, the calculations were carried out for a reference cross-section consisting of softwood lamellas only. By comparing the combined and reference crosssections, it can be stated that the use of the combined cross-section can save material for both the compression member (column) and the member subjected to bending moment (beam, girder). The combined cross-section appears to be more advantageous than the reference crosssection, especially in cases of smaller beam depth. [ABSTRACT FROM AUTHOR]

The term of gamification has now gained a reputation with both the public and the academic community. Gamification is aimed at integrating gaming elements into a non-gaming environment. Thus, it is situated, as the name itself may suggest, at the intersection of work and entertainment. It shows a very close relationship to game studies, but it doesn't represent a game directly, especially in terms of visual and narrative character. In practice, gamification makes use of a large number of motivational elements which inspire the user not only to start the required action, but to accomplish it as well. This thesis is aimed at defining the term of gamification itself, presenting information related to the term of gamification, such as its origin and evolution, gamification classification, practical uses of gamification and, last but not least, showing some examples. [ABSTRACT FROM AUTHOR]

The aim of the paper is to state the possibilities and roles of media statements on the relations between Russians and Czechs during intercultural cooperation in the field of inbound tourism in the Czech Republic. The paper expands and complements the conclusions of the research of the co-author's dissertation. These became the theoretical basis for a contribution to the discussion of whether the media can contribute to a higher level of relations between the nations and possibly remove the different expectations of both Russians and Czechs in the provision of services and their use in inbound tourism. [ABSTRACT FROM AUTHOR]

Copyright of Urbanismus a Uzemni Rozvoj is the property of Institute for Spatial Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Urbanismus a Uzemni Rozvoj is the property of Institute for Spatial Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper deals with experimental research of stability behaviour of laminated structural glass beams. The purpose of the research is the evaluation of lateral-torsional buckling resistance and actual behaviour of the beams due to absence of standards for design of glass load-bearing structures. The experimental research follows the previous one focusing on measuring of initial geometrical imperfections of glass members and experimental evaluation of flexural buckling resistance of structural glass columns. Within the frame of the research 9 specimens were tested. All of them were of the same dimensions - length 2400 mm and width 280 mm but different thicknesses - 12, 16, 20 mm. All the beams were composed of two annealed glass panes bonded together by PVB foil. Beams were loaded by couple of forces symmetrically situated to the mid-span and supports complied with fork boundary conditions. Specimens were loaded by constantly increasing force up to failure. During testing lateral deflection, vertical deflection, angle of torsion and normal stresses at mid-span were measured. Maximum bending moment achieved during testing has been adopted as lateral-torsional buckling resistance. From these values were calculated characteristics and design values according to the EN 1990. Experiment results were compared with lateral torsional buckling resistance calculated according to the buckling curves approach. [ABSTRACT FROM AUTHOR]

In this paper measuring and determining of initial geometrical imperfections of set of glass members are presented. Measured specimens had the different dimensions and different composition - monolithic glass or laminated glass using different types of interlayer foils and glass panes. The shape of initial overall bow was measured using different methods and results were statistically evaluated and compared with allowable values defined in standards. [ABSTRACT FROM AUTHOR]

This paper deals with experimental research of axially loaded members made of structural (laminated) glass. The purpose of the research is the evaluation of buckling strength and actual behaviour of the columns due to the absence of standards for design of glass load-bearing structures. The experimental research follows the previous one focusing on measuring of initial geometrical imperfections of glass members. Within the frame of the research 15 specimens were tested. All of them were of the same geometry (length 1500 mm, width 150 mm and thickness 12 mm) but had different composition – monolithic glass or laminated double or triple glass made of annealed or fully tempered glass panes bonded together by PVB or EVASAFE foil. Due to rectangular cross section and considered boundary conditions, flexural buckling perpendicular to the weak axis of the cross section occurred. During the testing, lateral deflection and normal stresses at mid-span were measured. Maximum force achieved during the testing has been adopted as buckling strength. Euler's critical loads and equivalent geometrical imperfections were evaluated using a Southwell's method. The results of experiments were statistically evaluated according to the European standard for design of structures EN 1990, appendix D. There are significant differences between the specimens made of annealed glass or fully tempered glass and between the specimens laminated with using PVB or EVASAFE foil – the differences are in the values of buckling strengths and load – deflection, load - stress plots. The next step was to determine the design strength by calculation procedure based on buckling curves approach intended for design of steel columns. [ABSTRACT FROM AUTHOR]

This paper deals with the problems of analysis and the design of perforated thin-walled steel Sigma beams with respect to lateral torsional buckling (further LTB). The application of Sigma profiles is in the storage systems and expedient flooring structures as floor girders. In some cases, the beams are not laterally restraint and therefore the effect of lateral torsional buckling may occur. First the theoretical calculations according to the design procedure listed in European standard EN 1993-1-1 and Czech national annex NB.3 are being performed. These calculations are valid for the beams with the uniform cross-section only without any rules for the beams weakened by holes. Therefore the substitute cross-section is being established and the cross-section characteristics are defined as the weighted average of the characteristics for the full section and for the section weakened by holes. The calculated elastic critical moments for the substitute cross-section properties are verified by the FEM calculations on the beam with variable cross-section. This theoretical approach is verified by testing in laboratory conditions. The experiments are being carried out on the specimens of three different beam lengths. The test results are statistically evaluated according to EN 1090 and the characteristics bending resistances obtained from tests are compared with the values calculated according to EN 1993-1-1 and Czech national annex NB.3 using the cross-section characteristics of substitute cross-section. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze implementation of the Corporate Social Responsibility by small and medium-sized organisations in creative industry using the CSR Canvas. The CSR Canvas was developed specifically for organizations of this size and is based on results from the empirical research of which results were periodically presented on several CPCI conferences. The Canvas helps to develop and implement new CSR activities as well as measure their impact, doing so it promotes proactive approach to CSR which is crucial for small and medium-sized organization. It was proven by several studies that only proactive approach enables these organizations to gain benefits coming from implementation of CSR. The paper analyzes a case study by using the method of qualitative data analysis. The case study shows not only the implementation of CSR but also the results and benefits of these activities, which is important for the long term performance. The implications help to promote positive effects of CSR for SMEs and it also helps to understand how SMEs from creative industry make their decisions about CSR. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the relations between time and cause as they are reflected by the French conjunctions. First, applying the diachronic point of view, we show which conjunctions expressing temporal relations are considered by different grammarians as being able to express causal values as well. After having described different types of principals that the causal implication is based on, we confirm the universal validity of the anteriority of the cause to its effect, even if language seems not to observe it in some cases. The adage “post hoc ergo propter hoc” explains well why the conjunctions of anteriority can easily express causal relation. In the second part of our paper we test the real capacity of different conjunctions we analyze to express the cause independently on the meaning of the clauses they link. We propose a coherent description of the functioning of each type of conjunction considered from the point of view of the relation between time and cause. [ABSTRACT FROM AUTHOR]

The recent COVID-19 pandemic affected various aspects of life. Several studies established the consequences of pandemic lockdown on air quality using satellite remote sensing. However, such studies have limitations, including low spatial resolution or incomplete spatial coverage. Therefore, in this paper, we propose a machine learning-based scheme to solve the pre-mentioned limitations by training an optimized space-time extra trees model for each year of the study period. The results have shown that our trained models reach a prediction accuracy up to 95% when predicting the missing values in the MODIS MCD19A2 Aerosol Optical Depth (AOD) product. The outcome of the mentioned scheme was a geo-harmonized atmospheric dataset for aerosol optical depth at 550 nm with 1 km spatial resolution and full coverage over Europe. As an application, we used the proposed machine learning based prediction approach in AOD levels analysis. We compared the mean AOD levels between the lockdown period from March to June in 2020 and the mean AOD values of the same period for the past 5 years. We found that AOD levels dropped over most European countries in 2020 but increased in several eastern and western countries. The Netherlands had the most significant average decrease in AOD levels (19%), while Spain had the highest average increase (10%). Moreover, we analyzed the relationship between the relative percentage difference of AOD and four meteorological variables. We found a positive correlation between AOD and relative humidity and a negative correlation between AOD and wind speed. The value of the proposed prediction scheme is further emphasized by taking into consideration that the reconstructed dataset can be used for future air quality studies concerning Europe. [ABSTRACT FROM AUTHOR]