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Although hydropower is one of the oldest energy sources used by man, it is still the leading green, nonpolluting and renewable source for electricity generation worldwide. Hydroelectric power generation is also the most efficient method of large scale electric power generation. Estimates show that there is a huge worldwide capacity of unutilized hydropower potential. Therefore, there are many opportunities for new hydroelectric power plants throughout the world, which makes the study and design of new and improved...

The article deals with of a hydrogen pressure vessel suitable for high pressure of approximately 75 MPa. One of the goals is to design a vessel from materials whose strength will meet mechanical requirements a calculated in both analytical and numerical ways. Another objective is the simulation of the design the pressure vessel with regard to safety and weight requirements.

Development of high strength concrete has been continuous over the years, its production becoming available at competitive prices to the construction industry, thus moving away from being a novelty product. Although high-strength concrete properties have been widely studied for nearly 100 years, currently available design standards for concrete structures contain stipulations based on research conducted on concrete with lower grades than those available today. The modulus of elasticity is a very important mechanic...

The territory of Slovakia is in Central Europe at the interface of the parts of the continent that are influenced by continental and by oceanic climates. This is reflected in the variability of weather and climate characteristics. Apart from traffic load, change of climatic conditions are one of the constant external factors with adverse effects on physical and mechanical properties of different structural multi-layers in pavements. These impacts together with frost index and their corresponding changes significan...

When operating waterworks, it is required to refine the data on actual stresses in different structural elements of the facilities. The authors put forward a nonconventional approach to expanding the waterworks observation network. The quantitative assessment of stresses in a structural element at the given moment of time is performed using borehole techniques of geomechanics. Later on, the change in the stresses and deformations is controlled based on the data on deformation of sidewalls and damage of galleries u...

The authors have carried out uniaxial compression tests of 200 mm side cube specimens made of artificial layered geomaterial with the bedding angles of 0, 30, 45, 60 and 90 deg and with the different strength of the layers to study the process of deformation to failure using the multiparametric equipment designed for synchronous recording of physical fields of stresses, macrostrains, microseismic emission (MSE) and microstrains by speckle method. The integrated analyses of MSE signals, microstrains, stresses and s...

When it comes to workplaces characterized by a high degree of hazard and liability, such as mine intervention and rescue in major risk environments the most important element is the convergence of the skills required by job and skills of the individual, this being the guarantee of successful vocational selection. Along with psychological selection, training / retraining and physical training in conditions as close as possible to the reality of future interventions, under the action of stress factors that cause neg...