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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]

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]

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]

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