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Currently, the question of studying the functional reserves of the body of healthy athletes of high qualification is becoming relevant worldwide. To achieve high sports results, including the Olympic level, more and more efforts are needed since the rate of records is higher and higher. The intensity of sports training is increasing but sometimes it is difficult to do without special medical support, namely sports pharmacology. Due to the active anti-doping campaign, the use of previously traditional methods of fa...

The dynamics of oil production growth observed in the world is conditioned by intensification of oil resource development related to hard-to-recover fields, particularly, shale oil recovery that has allowed for the USA to become a leader in the world production. The common petroleum and gas production technique is hydraulic fracture treatment, which has become an issue of public concern as to its environmental safety. There is an ambivalent attitude towards this technology in the world. In some countries it is for...

The fixture of optical elements in optomechanical assemblies is a field that develops depending on ever-increasing demands on optical systems, namely on their performance, the accuracy of the fit for the lenses, on the installation space, the resistance of the assemblies, etc. Equally important is the view in terms of the production demand for such a system, which is also growing. The article presented here deals with a theoretical understanding of the issues concerning the free bonding of lenses, i.e. fitting the...

The paper presents a methodology, based on artificial neural networks, for the offshore wind speed values long-term prediction. One of the most available renewable energy is the wind energy. The offshore wind turbines placement presents some benefits comparing with onshore one, like lower environmental impact and long-term stability of surroundings geometry. Of course, there are also drawbacks, like difficult set-up and maintenance or expensive transmission systems for the converted energy. Over all, the off-shore...

Foam glass is one of the materials for which it is possible to use glass waste of lower quality, which cannot be used for the production of classic glass products. Foam glass aggregate is a very interesting raw material, which, although it does not reach the quality of conventional foamed glass, but has a number of very interesting properties, thanks to which it can be used for the production of composites with a very good ratio of thermal insulation, acoustic and mechanical properties. The paper describes the res...

Geophysical surveys of wells represent a wide range of methods, the rational integration of which make it easier the solution of geological problems. In this article, the authors investigate the issue of identifying the parameters of hydraulic fractures. This method is one of the frequently used methods for increasing well productivity. Modifications of nuclear logging and the possibility of acoustic logging are considered on the example of data before and after hydraulic fracturing in carbonate and sandstone depo...

The article builds on scientific work, which in the framework of the in-the-go analysis has identified a practice-making problem for the performance of air rescue services in the field, with an emphasis on the network of landing areas, their information (technical) security and the risks associated with the decision-making process for conducting the flight under minimum time disposition conditions for the safe achievement of the landing area and the rescue helicopter landing itself on the selected area. The emerge...

A directional coupler is a passive device designed to divide the power between its outputs in a given ratio. The value of this ratio depends on the resistances of the segments with which the device is assembled. It is important to understand how the miniaturization efficiency of a 3 dB directional coupler varies at different operating frequencies. Modeling and calculation of the characteristics of the devices was carried out in a specialized program Cadence AWR. The first step in the work was the design of taps ac...

In the presented study, new types of lightweight plasters for passive moderation of interior climate were designed and tested. The examined plasters were composed of blended mineral binder (cement-lime or gypsum-lime), silica sand, perlite, chemical additives, and batch water. For the basic characterization of studied materials, bulk density, specific density, and total open porosity were measured. The mechanical resistance of the developed plasters was assessed in flexural and compressive strength tests. The ther...

Agricultural land is an important natural resource exploited for agricultural production to provide food for the population. The pressure on agricultural resources has increased in the world, as the population grows and non-food land uses increase. In Latvia, the utilized agricultural area (UAA) has decreased since 1991, and in 2020 it was 2.3 mln. ha or 36% of the total area of the country, while the forest area increased, and in 2020 it was 3.1 mln. ha or 48% of the total area. In 2019 in Latvia, the unfarmed an...

Irregular digital models (TINs), which are expensive, are used to model engineering structures, terrain surfaces and hydrography. Interpolation with regular digital models are more affordable at the expense of accuracy. There are many methods for interpolating surfaces, depending on the purpose, the appropriate models are selected. The paper presents bilinear, bicubic interpolation and interpolation with Bezier polynomials. The aim is to empirically compare the accuracy of interpolated surfaces with bilinear, bicu...

In the international context of air pollution, the issue of air emissions is treated with various measure in different geographical areas in the world. Due to this necessity, international stakeholders were taking sets of regulations to reduce the effects of air emissions resulted from shipping activities. In Black Sea, because of geopolitical context, such measures have not yet been taken into account. The Black Sea area represents an important pole in the Eastern European trade and is reflected in the transit of...

The management of medical facilities' primary task is undoubtedly the quality of treatment and ensuring patient safety. With increasing knowledge, new technologies, and the growing complexity of treatment procedures and methods, the probability of the occurrence of risks and, in some cases, the emergence of new risks are increasing. An adequately set up a risk management system in healthcare facilities has a fundamental impact on the crisis preparedness of these facilities and the effectiveness of the entire manag...

Garlic (Allium sativum L.) is among the main bulbous vegetable known worldwide for both economic and health value. The research was conducted in the framework of the project on the modernization of winter garlic cultivation to ensure guaranteed yield in the organic production system. The new technology is designed to prevent the effects of unfavourable soil and climatic conditions on the rooting and wintering ability of garlic ? factors that significantly affect the garlic production in Latvia. Field studies were ...

Producing non-seasonal vegetables in Georgia is actually impossible without greenhouses and specially-designed constructions. Greenhouse enables us to be less depended on environmental conditions, as well as to accumulate sun power and to artificially regulate all necessary factors for growth and development of various plants, to protect plants from unfavorable and adverse nature affects such as hail, wind, draught and freezing. In open ground soils the producing process of vegetable crops terminates as soon as un...

The area of intensively polluted territories in the world has been constantly increasing. The ecological situation within such territories is rather difficult. As to Russia one of these territories is the Urals. It is the populated region with a lot of wastes after very long period of mining activity (extraction of gold, platinum metals, salts, coal, diamonds, precious stones, copper, iron, oil, etc.). The special litho-monitoring program is worked out by the Perm University scientists with the purpose to control ...

Floods are one of the most frequent natural disasters in Slovakia. The suggestions of flood protection measures were already taken by our ancestors many centuries ago. During the recent years, the attention of public and professionals, as a result of floods in Slovakia, is markedly focused on the possibilities for effective protection against the harmful effects of this negative natural phenomenon. One of the flood protection measures to protect towns and villages, or other important buildings, is a realization of...

Mining activity entails accumulation of sulfide?bearing mill wastes with high concentrations of ore elements (Fe, Cu, Zn, Cd) and impurities (As, Hg, Be, and Tl). The volumes of hazardous sulfide-containing mining waste in non-equipped storage facilities according to modern standards reach several billion tons in Russian Federation. The handling of abandoned waste in our country is not currently regulated, the question remains open: there is no established methodology for estimating stockpiles and handling of wast...

Today, distance learning does not surprise anyone, most of the educational institutions of various levels abroad, to one degree or another, use distance technologies in the pedagogical process. Many students today consider this form of education as an alternative to the usual one, not only when receiving a second education, advanced training, but also choose this method for obtaining the first higher education. There is nowhere to go from current trends, and many universities understand this and are trying to deve...

The aim of the presented paper is to give a review of the classification of atherosclerotic plaques between two different input values; using computer image analysis and a visual assessment by an experienced sonographer. In the case of computer analysis, the echogenicity index (Echo-Index) is used. In the case of visual assessment, echogenicity of the plaques have been evaluated from histological patterns. In the case of computer image analysis, B-images have been processed. To computer image analysis, our develop...

The long-term activity of a polymetallic ore mine in the region of Tarnita-Suceava, Romania, has resulted in an enormous amount of waste material, collected in tailing dumps and ponds. The impact of the waste materials on the surrounding ecosystem and human health are far to be fully estimated. The deposited waste has exerted negative impact on the environment, especially on the soils that host dumps and drainage waters. Heavy metals, including arsenic also interfere with the metabolism of plants, and reduce the n...

The climate in Latvia is moderately warm and humid. To provide optimal groundwater heads (levels) for plant and tree growth, agricultural and forest melioration systems (AMS and FMS) have been set up in many places. Reconstruction of the FMS ?Zamelu-Tisu mezs? will be carried out. To assess the reconstruction impact, hydrogeological and hydrological conditions in and around the FMS territory were studied. To accomplish this task, specialists of Riga Technical University for the study area developed and used the lo...

Dianthus superbus L. is mentioned as seriously threatened species in several European countries. In Latvia, D. superbus is endangered species on the edge of extinction and is included in the 1th category of threat in Red Data Book of Latvia. As the population has declined to critical levels, special studies and related protection measures are necessary. Therefore, investigation was done to reveal the current state and surviving potential of D. superbus in Latvia. Numerous expeditions were conducted to check 18 pre...

In this study, a procedure was developed for the synthesis of WO3-containing catalysts based on zeolites of the ZSM-5 type. Zeolites with different Si/Al ratios and different numbers of acid sites were used: ZSM-5-CVM, ZSM-5-CVN and ZSM-5-Acros. The synthesized catalysts were characterized and tested in the reaction of the conversion of fructose and glucose to 5-hydroxymethylfurfural and levulinic acid. It was shown that the introduction of tungsten (VI) oxide into the composition of ZSM-5 leads to a noticeable in...

The article discusses the information-cartographic approach to the visualization of educational information as a universal educational strategy aimed at the full development of cognitive processes, the imaginative thinking of students, taking into account the functional asymmetry of the cerebral hemispheres through the use of intellectual and graphic tools for visualizing educational information, creating a new communicative system of transition from verbal language to language grafting. The information-cartograph...

Earthquakes are violent movements of the Earth?s surface resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. The movements are characterized by rapid variations of direction, speed and acceleration. The present paper analyzes the response of the structures and the behavior of buildings during high-intensity earthquakes. The target areas of the study are Galati and Suceava municipalities, located in Romania, at varying distances from the seismic hotspot situated in the C...

The aim of the paper is to propose guidelines for a general virtual reality based framework for training people how to behave and evacuate in business buildings during disastrous events. Disaster is a chain of dangerous events or exposure to hazardous conditions, which could lead to harmful damages to people with an eventual loss of life or property. Such risk conditions can be managed by planning well ahead before disasters occur and by performing suitable training to avoid critical disaster consequences. The pap...

The article reports on detection of toxic effect of nanosized magnesium oxide on brain tissue of laboratory animals that have been given the substances via inhalation and orally. The experiment was performed on mature adult male Wistar rats (weight 250±15 g) and on BALB/C mice (weight 25±2 g). Detection of the nanoscale magnesium oxide toxic effects on brain tissue was conducted using multifractal image analysis of histology preparations with application of the binarization and constructing Voronoi diagrams from g...

The paper presents a synthesis of our researches on the main physic - chemical and biological parameters of the Snagov Lake, from Ilfov County, Romania, made since 2013 until 2019. We have developed complex investigations on the most important water quality parameters of the lake, in the purpose of analyze the evolution of the water eutrophication phenomenon in time, in different sampling points, also to establish the optimal methods of control and combat of the studied pollution process. Because the eutrophicatio...

The structure of the Romanian Western Black Sea shelf has been studied before 1970 and described in publications that serve today as an important point of reference in the structural geology and geotectonic studies. After the year 2005, a new set of gravimetric data has been acquired by the Romanian National Institute of Marine Geology and Geoecology, that has been obtained by compiling over 13.400 km of profile measurements on the Romanian and Bulgarian offshore. By combining this newer data with an analysis on t...

A soil-forming material, its texture and geochemistry, is one of the main natural factors for a grape plant, which is used to develop deep roots over a long life cycle. A plant mostly receives a wide variety of chemical elements from parent rocks, which affect the plant's growth and yield. The purpose of the work was to determine the ampeloecological specific features of the soil-forming materials of the Crimean Peninsula for grape cultivation. Based on the soil survey and GIS analysis, we substantiated four main ...

The study of regional characteristics of the bottom sediments physicochemical structure in semi-closed water areas (using the example of the Balaklava Bay) is especially relevant due to the fact that the recreational potential development rate of this region has significantly increased. During the studies, 3 columns (two in northern part of the bay and one in southern) of bottom sediments were taken and the activity of 137Cs, 210Pb, and 226Ra in them was determined. Column samples were taken using an acrylic soil ...

Research goal of the paper is mathematical description of the physical process of forming the surface waters quality on the example of the Lower Section of the Ingulets River. The methodology in which the chemical status of a water body (category and class of water quality) is assessed based on the analysis of observational data (concentrations of priority hazardous pollutants) was used. Based on a general assessment, the suitability of surface waters for use in various economic purposes is established. We propose...

This study is intended to develop educational technologies for disabled students with violation of musculoskeletal system. According to the World Health Organization the statistical data on diseases of the musculoskeletal system accounts for 30% each 10 years, as for the percentage disablement due to this factor it accounts for 25-30%. The Global Burden of Disease study reported that musculoskeletal disorders are ranked as the second most common cause of disability. The disabled people?s problems related to the pr...

The main purpose of the research is investigating approaches of nanostructural perovskite obtaining. We used wide known methods, which used for studying microstructure and electronics properties such as atom-force and scanning electron microscope, X-ray diffraction method. Halide perovskites have emerged recently as promising materials for many applications in photovoltaics and optoelectronics. Recent studies of their optical properties suggest many novel opportunities for a design of advanced nanophotonic devices...

The ability of a moving charge to create a vortex magnetic field around itself is well known. This phenomenon formed the basis for the creation of electromagnets. The reverse process is electromagnetic induction, when a magnet moving with acceleration becomes a source of electric current in a closed conducting circuit. In this regard, ferromagnetic fluids are of some interest. Ferromagnetic fluid is an aggregatively stable colloidal system consisting of nanosized particles of a dispersed phase uniformly distribute...

Worldwide, political framework reaffirmed sustainable development as a central element of the international agenda and give a new impetus to the practical application of the global measures to combat the negative effects of human actions and for the environmental protection. Since mid 2010, petrol consumption in the transport sector has increased at a higher rate than in other sectors. The transport sector generates 35% of the total CO2 emissions. In this context, strategies have been adopted to use clean energy, ...

The article deals with the development of geoinformatics procedures accelerating and simplifying the application of the scattering model SYMOS?97 (Gaussian model), for selected pollutants in the open air to an area with a large number of sources and reference points. They are compared here with real measured concentrations of these persistent organic pollutants. One of the chapters illustrates the spatial and temporal variability of the ratios of the contributions of individual resource sectors to the total air po...

The purpose of the work is to determine the patterns of influence of biotechnological and physical methods of processing raw materials on the quantitative indicators and amino acid composition of protein concentrates obtained from chickpea grain. With the use of enzyme preparations, the yield of soluble chickpea protein reached up to 60% of the total content in raw materials. The regularities of the effect of ultrasonic treatment on the solubility of the proteins of the suspension of chickpea flour with an increas...

This paper presents the results of the comparison of various measures to reduce the indoor air temperature in the attic room in summer. The building with attic rooms in Brno in the Czech Republic was chosen for this research. The building was modeled in the DesignBuilder software and compared with the measured results in the given period to optimize the model. After verifying the correctness of the model, six different alternatives of shading measures were one by one added in the model, and simulations were run. O...

The purpose of this report is to show possible ways to improve the information access for societies in developing countries possessing significant mineral reserves and mining industries, which considerably affect the welfare of national economies and population. The research methodology is based on the provisions of official regulatory documents, methods for processing and analyzing statistical data related to the subject of the research, demonstration of the results characterizing the state and dynamics of the in...

Scientific and technological development is an important requirement to ensure the development of geodesic and cartographic fields. At the same time, science and technology have also been identified as key in socio-economic development in the context of the world applying the great achievements of the Industrial Revolution 4.0. Technological changes in measurement and mapping such as satellite positioning technology, digital technology, network technology, etc. have been changing methods of receiving, processing i...

This paper presents a theoretical study on the free convection of pore water in saturated permeable rock mass during artificial freezing. Artificial freezing technology is widely used in the construction of mine shafts, tunnels and other types of excavation that take place under high water content conditions or conditions of high levels of groundwater seepage in soil and rock. A qualitative analysis of artificial freezing in water-saturated permeable rock mass shows that the effect of free convection can be signif...

Anthropogenic activities disrupt hydrological regime (e.g. lake water level, river flow), and water quality changes due to pollution and affect ecosystems by disrupting the cycles of substances and water cycle. The composition of natural surface waters can be altered for a many reasons, for instance climatic, geographic as well as anthropogenic. Agriculture depends on a use of fertilizers, a use of pesticides, and a transport which turn agricultural land into a nonpoint source of surface water pollution. The agglo...

Importance of unmanaged forests for biodiversity aspects in unquestionable, while their role in climate change mitigation is still unclear due to the large heterogeneity of these forests in different bioclimatic regions; therefore, requiring data of biomass distribution for their inclusion in national and regional carbon reporting systems. The aim of our study was to assess the live biomass distribution and amount of dead wood in over-mature Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (K.) L.) ...

The planted forest stands of pedunculate oak (Quercus roburL.) were carefully cultivated in Latvia for wood harvesting since the end of the 19th century. Today, felling of Q. robur forest stands in Latvia is prohibited, and according to the nature conservation rules are included in the list of habitats of European interest 9160*. According to the State Forest Service [14], the share of oak stands in all forests in Latvia is 0.1% (9354.58 ha). During their lives, oak forest stands are threatened by various risk fac...

A large number of precious metals such as molybdenum, gold, uranium and much more are obtained from sulfide ores. Currently, a large number of hydrometallurgical methods are used to extract precious metals, which in turn are outdated in this field. In this regard, it is necessary to develop new modern methods for extracting all valuable components from sulfide ores. One of these methods is the process of bio-leaching with the use of microorganisms. The use of this method in mining companies will help reduce the ri...

Currently in the field of BIM design, the Czech Republic is in many ways behind compared to other countries. In countries in which this method is long established, it makes a significant contribution to improving the economic and environmental efficiency of buildings in all life cycles of construction. The BIM method can save construction costs and conserve the environment, by appropriate design of technical and technological equipment, as early as the preliminary stage of a project, but also when building is carr...

The present study analyzes the potential changes of residential heating and cooling degree-days as well as three stakeholder-relevant indices of agro-meteorological change (growing season length, sum of the active and sum of the effective temperatures) for Southeast Europe over near past (1975?2004), near (2021-2050) and far (2070?2099) future periods. All indicators were calculated from the output data of our simulations with the regional climate model RegCM driven by the ERA-Interim reanalysis for the near past ...

In the present work the researches were carried out in the Tata Valley watershed, which has an area of 17 km2 and administratively belongs to Dambovita county, Romania. The purpose of the study was to estimate the soil losses for a single storm event in the Tata Valley watershed using the MUSLE method and G.I.S. The identification of the erosion processes and the estimation of the quantity of eroded material is extremely important both for the elaboration of the risk maps, as well as for the analysis of the surfac...