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The paper describes a new design of a directional coupler with four plug-in quarter-wave loops. Four loops increase the operating frequency band several times, but the area of the device also grows by two quarter-wave segments in length. It is not always possible to use such a large device area, for this reason, techniques are used to reduce the size of the device with minimal loss in its characteristics. Using miniaturization, which is the use of compact structures, it was possible to reduce the size of a quarter...

It is well known that the main purpose for all upscaling techniques related with homogenization of initial any heterogeneous property and substituting it with an effective value. Thus, the essence of upscaling is computing weighted average on the fine-grid to form coarse-grid considering representative elementary volume. The goal of this research work was experimental investigations of pore space distribution of carbonate rocks. Samples were collected from the Upper Permian ages core data. Samples bulk porosity we...

Acrylic derivative-based superabsorbents are widely used currently in agriculture as the soil conditioners, plant growth regulators, etc. Their usage has a positive effect on the growth and survival of the plants cultivated in the arid regions. However, the effects of hydrophilic acrylic polymers on the soil microbiocenosis still remain unknown. The influence of the moisture-absorbing acrylic acid-based hydrogels with different concentration of bentonite filler was studied on the soil microbiota. N,N-methylenebisa...

A supervised classification algorithm has been developed for automated sea ice retrieval in some regions of the Arctic seas. Sentinel-1 Extra Wide images were utilized as input for a Neural Network (NN)-based algorithm. Synthetic aperture radar (SAR) data has several features significantly affected on the microwave backscatter from sea ice. In this paper, an approach to improve data quality is proposed. Since different sea ice types can have similar backscattering coefficients, the extracted SAR texture features i...

The Cieszyn Tufa Springs is a special area of conservation located in the Western Carpathians (southern Poland). The main subjects of protection are springs that outflow from the contact zone between Cretaceous limestones and slates. Due to a high vulnerability of shallow aquifers within the area of Cieszyn Foothills as well as urbanization and highly-developed industry of the Silesia region, a wide range of contaminants is detected in the spring water. Although microcomponents present in water of the mentioned ar...

Internet of Things (IoT) has a different meaning to different people. The term has been known for a long time. The use of interconnected devices has become more and more necessary to solve established business problems. It turns out that data acquired from IoT sensors and controllers are valuable enough to have the power to change the overall business models and behaviour of entire industries in a given economy. Therefore, the future of IoT as a cutting-edge technology depends on the security capabilities that IoT...

This work is about paleogeographic reconstructions on the basis of mineralogical and geochemical studies. Vanavar, Oskobinsk and Sobinsk formations of the Vendian age (Ilbokichskoe deposit in Eastern Siberia) were studied. The complex of research included data of XRD and ICP-MS. According to the obtained results, the mineralogical composition of the sediments was refined. Quartz, carbonate minerals, represented by magnesite, dolomite, calcite and siderite, and sulfates ? gypsum, barite, anhydrite are noted among t...

In this paper, we present the spatial distribution of sedimentological and geochemical characteristics of the bottom sediments of Vouliagmeni lake which is located in the SW Perachora peninsula extending into the eastern Gulf of Corinth, Greece. A total of nineteen (19) samples consisting of upper 1-2cm lake bottom sediments were collected and analyzed. Standard sedimentological analyses were carried out including grain size analysis and the measurement of calcium carbonate content (CaCO3), total organic carbon (T...

The American NASA Apollo missions to the lunar surface, between 1969 and 1972 greatly increased the knowledge of the Moon as well as that of our own Earth's age and origins. Part of the scientific research used geophysical techniques to help define the structure of the Moon, both deep and also regarding the near surface. One such experimentation that was carried out, on both Apollo 14 and Apollo 16, as part of the Apollo Lunar Seismic Experiment Package (ALSEP), was the Active Seismic Experiment (ASE). The ASE com...

The paper considers the problem of velocity model reconstruction of an elastic medium in the problem of monitoring the zones of underground nuclear explosions. The inverse problem can be solved with help of finding solutions for a set of forward geophysical problems. Main problem is to find the location coordinates and treat to find the characteristic size and shape of cavernous object in entire isotropic elastic media. To realize it the problem statement and the description of basic methods to perform full seismi...

The study is based on seismicity data analysis, using seismological data available from published local, regional and global earthquakes catalogues. Seismicity data for Romania, Bulgaria and the Western Black Sea have been compiled into a unique data-base and represented within a georeferenced framework. A large number of seismicity maps at various depths and depth intervals, as well as W-E, N-S and NE-SW in-depth seismicity graphs have been built. The regional structure of interest is the Intramoesian Fault (IMF)...

The Apuseni Mountains are located in the western part of Romania and are limited to the west by the contact with Pannonian Depression and to the east by the Transylvanian Basin. Basically To the south Apuseni Mountains are bounded by the South Transylvanian Fault and in the northern part by the North Transylvanian Fault. Apuseni Mountains represents an isolated massif inside Carpathian arch, consisting of complex folds and thrust belts formed in Cretaceous period as results of interactions between multiples microp...

The efficiency of drilling and blasting works can be assessed in many ways, depending on the desired effect. The evaluation can be performed on the basis of the quality of the explosives used for rock extraction. On the other hand, the correct assessment should include the results of drilling and blasting works. One of the parameters that are commonly used in the quality evaluation of explosives is the in situ velocity of detonation measurement, which is a direct indicator of the efficiency of the utilised explosi...

The solving of the project of the Czech Republic Technology Agency TACR dedicated to microbial methane genesis in geological conditions of the Czech coal basins is under way from 2018. The target of the project is clean methodology of coal. The main attention of the 2018 research was devoted to the geological research of the brown and hard coal basins and to the selection of the optimum localities for sampling. This paper briefly summarises the geological situation of coal basins, stratigraphy of different coal se...

In recent years, research and development works have been carried out in our country to create a modification of the sprinkler machine ?Kuban-L? with a set of equipment for controlling the sprinkling height (including the surface one), which allows reducing the average rain intensity and reducing the loss of irrigation water for evaporation and demolition by the wind. There are a number of issues that need to be clarified, despite the large degree of this product?s development such as the distribution of the quali...

The results of laboratory studies concerning self-ignition in Central Europe are presented in this paper. There are known cases of self-ignition of peatlands in Indonesia and tropical regions of Africa, as well as in Southern Europe (for example in Italy and Spain). Therefore, there is a possibility that this phenomenon could also occur in Central Europe due to a climate warming. The laboratory studies, using adiabatic calorimeters, were carried out to assess the tendency of peat to self-ignition. The main aim of ...

Design, development and support of the user interface is a very important and time-consuming task in the development of the information system as a whole. User interface development is usually organized by a life cycle model describing activities from the initial idea to the final implementation and performance testing. The problem with such approach is that the model requires correct and complete understanding of the final complete user interface design project from the very beginning, because correcting a mistak...

Mathematical modelling is a powerful tool when it comes to studying and solving complex hydrological problems ? studying the hydrological regime in a changing environment, hydrological forecasting, flood risk estimation and etc. There are different types of hydrological models depending on their characteristics and an in-depth knowledge is needed to use the most appropriate one for a given purpose, e.g. evaluation, planning, forecasting. Indispensable part of building a trustworthy hydrological model is performing...

jewellery, construction materials, in the mechanical systems and energy generation). The popularity of the use of copper alloys caused an increase in the application of these materials and the increase in the demand for recovery of previously used metals that are components of these alloys. The sources of materials from which the above-mentioned metals are recovered can be: brass scrap, elements from electric furnaces, electronics, car scrap and alkaline batteries. Thus, in recent years, the demand for the recover...

In this paper we describe the synthesis and characterization of nano-sized TiO2 particles supported on sepiolite fibres with sepiolite to TiO2 weight ratios of 30:70, using sepiolite from Korinthos, Greece. Sepiolite - TiO2 nanocomposites were prepared by deposition of anatase form of TiO2 on the sepiolite surfaces using a sol?gel method with titanium isopropoxide as a precursor under hydrothermal treatment at 180 °C. The characterization includes phase composition, particle morphology, while the physical properti...

The fouling is closely related to the corrosion of materials, repeatedly increasing the speed and extent of damage to marine equipment and infrastructure. Therefore, it is very important to search for effective ways to combat corrosion and fouling, to prevent them. All this is impossible without a careful study of objects - fouling organisms. Bench testing with the application of test plates is the most available and widespread method to study the development of fouling. In the winter of 2018-2019 has been investi...

The Black Sea is the largest marine anoxic basin in the world, connected with the Mediterranean through the Bosporus Strait, Marmara Sea and Dardanelles Strait. During global ocean low-stands, the Black Sea basin was isolated from the Mediterranean evolving as a fresh-brackish giant water body. In the Late Pliocene ? Pleistocene times, the Black Sea experienced periodic influxes of water from the Caspian Sea through the Manych Corridor. These hydrological changes that occurred in the Black Sea basin had greatly in...

This work is related to the analysis of two complicated pipeline sections (section «A» and section «B»). Rheological properties (hydrometer MARS?II Haake) of produced and transported fluids. Hydraulic calculation of the technological process of fluid transportation from the well sites to the oil collection system was performed. Hydraulic modeling carried out with the help of PIPESIM software. The input data for process modeling were the results of investigations of rheological properties of transported fluids and ...

The article describes an effective simulated model of international timber transportation, which is a part of support methodology for the selection of a transportation scheme of international timber transportation. The main objective of the developed model is to increase the economic efficiency of international timber transportation. Using the simulation method is due to its availability and cost-effectiveness. The initial data used in the model are experimental data (time spent on the moving from the loading poin...

It has been observed that during high carbon ferromanganese using South African ores, some practices do not find an easy answer from the theory and vice-versa. It has therefore become important to study under different reducing conditions what paths does the slag go through while forming during reduction in order to better understand its formation while higher manganese oxides are being reduced. The carbon monoxide gas amount and availability in a specific zone albeit its origin is influential and explanatory towa...

Supervisory Control Theory (SCT) is a general technique to synthesize controller for Discrete Event Systems (DES) such as manufacturing systems, robot systems, communication systems, transport systems etc. The controller for DES is also called as supervisor. The SCT uses formal languages and automata concepts for supervisor synthesis. In SCT, a plant can be modeled by using automata. This automaton is an event sequence generator. Uncontrolled behavior of plant is defined by these generated sequences. The desired c...

The topicality of this study: The corporate social responsibility (CSR) became a particularly topical issue in the field of entrepreneurship since Latvia has joined the European Union in 2004, as well as for Bulgaria as the country joining the EU. All business companies are asked to undertake the strategy of social responsibility and to adopt the principles of social responsibility. In the context of this study, a sustainability strategy is adjusted to the specific economic, social, environmental and cultural fact...

In a world faced with the twin challenges of increasing urbanization and climate change, it is paramount to re-think cities so that they are able to face the pressures these changes will bring. Smart Green City goes one step beyond smart cities and is committed to caring for the environment. The Smart City, undoubtedly, has many advantages, and the implementation of all the technology associated with it is almost immediate. However, there is another emerging concept that, although it has less relevance, is also ve...

Air pollution in cities caused by traffic is an important environmental and health issue worldwide. Air pollution caused by traffic exceeds air pollution from other anthropogenic sources, such as industrial, various heat supply and residential areas. This study analyzes a wide range of pollutants in snowpacks at different intensity roads in one of the largest cities in Latvia in Jelgava. Snow samples are taken from three sampling points at distance of 1 m, 10 m, and 20 m from the roadway. In the study, various met...

Traditionally, the rural areas are characterized by a lower level of social sphere development, a limited range of services offered, difficult access to part of the population, etc. The demographic resources of these territories have specific features and require target development policies that will limit the depopulation of the rural areas. The social entrepreneurship is seen as a mechanism for solving social problems in rural areas and social enterprises are seen as a way to promote the active integration of vu...

For the construction of alternative and sustainable cities of the future, due attention should be paid to the study of the socio-economic and political issues that result from the development of globalization processes. On the other hand, smart and sustainable cities of the future are the challenge of the 21st century faced by the local authorities of the cities and regions of the European Union, as regional imbalances must be reduced by discussing cohesion issues. The process of building and managing alternative ...

Web applications nowadays are quite a common asset for any big service-oriented organization. Communication and interaction are done very easily on the Internet. The purpose of this paper is to offer a close look at several web systems that work and fulfill the needs of the academic and student communities within University of Economics ? Varna. Those systems have been operating for a period of 3 to 5 years and continue to grow in scope. We present an in depth comparison of available software solutions on the open...

Regular measurement of rock deformation processes makes it possible to make judgments about the nature of the deformations of the Earth's crust, as well as the likely precursors of earthquakes near the area where these data are obtained. Therefore, the continuous operation of measuring devices that record such deformations is extremely important. When measuring by laser methods in a normal atmosphere, the distance of measurements can be significant, up to 25 meters and higher. The disadvantage of such measurements...

The taiga zone of the West Siberian Plain is characterized as a zone with risky agriculture. First of all, this is due to the natural climatic conditions of the northern part of the area under study. The soil and ecological evaluation of grasslands proves the possibility of feed production for dual-purpose cattle due to the natural fertility of Ob and Vakh floodplains alluvial soils. The study of these soils for evaluation of their soil, agrophysical indicators is based on the methodological basis of the soil-ecol...

Soil contamination is one of the most serious environmental problems. The aim of this study was to assess the level of contamination of soil by hazardous metals in 5 regions of Slovakia. Overall 152 samples (soil + plant) were collected from 76 sampling sites in investigated regions. In all samples contents of Zn, Cu, Ni, Pb and Cd were determined. In soil samples the total contents of risky elements in extracts by aqua regia as well as contents of bioavailable forms in extracts by NH4NO3 (c=1 mol/L) were determin...

Vertic Solonetz is a particular soil group with soil profile comprised diagnostic horizons and properties of both Solonetzes in the solum and Vertisols in the subsoil. The aim of project is to study genesis and geography of Vertic Solonetz on the basis of detail soil mapping for key plots from different regions at the East-European Plain: the Oka-Don Lowland, the Kalach Upland, the Northern Caspian Lowland, denudation plains at the Kerch Peninsular. Soil mapping is carried out by using GIS, field morphological des...

The Oltenia Mining Basin extends, intermittently from west to east, from the Danube to the Luncavat Stream, Valcea County. It is located as a fan shape at the contact area between the Getic Plateau and the Mehedinti Plateau, to the west of the Motru River and the Subcarpathian Depression of Oltenia, to the east of the Motru River, with the mention that most mining objectives are to the south of the contact area or in the immediate vicinity nearby.The surface mining operations in the Oltenia basin have affected lar...

Soil degradation, characterized by decline in quality, decreases ecosystem goods and services, and is a major constraint for further agricultural, including food, production. In addition, soil degradation caused by human activities, especially agriculture, contributes to climate change. The need to ensure a sustainable use of soils is outlined by the European Union (EU) Soil Thematic Strategy, as well as related legislation. This requires the prevention to further soil degradation and the preservation of its funct...

Both the United Kingdom as well as Czech Republic have seen increased impacts due to flooding in recent years. Rural flooding is due to intense and heavy rainfall-runoff events. Runoff brings with it soil erosion and sediment transport, so called ?muddy floods,? which causes serious onsite and offsite damages in the landscape or even in settlement area and infrastructure. Long-term observation and measurement is crucial step for understanding of complexity of processes involved in the generation of muddy floods an...

Biochar, as a product of carbon-rich thermal degradation of biomass, can increase crop yield and retention capacity of soil, improve soil quality and nutrient cycle. The use of biochar has positive effect primarily on soils with low quality, so its use in conventional agricultural temperate soils has often different effects and depends especially on the biochar feedstock and the pyrolysis process. There are not many research papers which are studying changes in biochar properties over time, i.e. whether the biocha...

Kozhukhovskaya metro line is under construction in the southeast of Moscow now. The geological cross-section at the construction site shows Carboniferous limestone at a depth of 30-65 m, overlain by Jurassic and Quaternary clay, loam, sand and sandy loam. The principle geohazards originate from the presence of the thick horizon of water-saturated sandy and sandy-loamy deposits. These deposits serve as an enclosing medium for the future metro tunnel. The deposits along the route were typified according to their res...

Windstorms are one of the main factors causing damages in forest in Northern Europe. The damages are especially severe, if the ground during the storm is not frozen and is wet, therefore the trees are less stable. Cyclonic windstorms primarily happens during the winter, and there is a prediction of notable rise of temperature in this period of the year ? thus we can expect more storm damages. It is known, that inside the forest stands specific microclimate exists, affecting also the soil temperature. However, ther...

Environmental pollution by manganese is a significant problem for the Imereti region. The source of pollution is derived from manganese extraction quarry and ore processing plant. The purpose of the study was to investigate the concentration of manganese and other heavy metals in the soil, air and water. Samples were taken from the industrial area, and the chemical elements were identified in them using ICP-MS. The results showed that the concentration of manganese and some other metals exceed to the permissible l...

The dolomite problem is very popular among geologists, who are especially working with oil-saturated carbonate rocks. Probably, this is the most common type of diagenetic transformation of limestone. However, the problem of secondary dolomitization is still insufficiently discussed, as a process associated with oil migration and oil-charge. The main purpose of this study is the geological reconstruction of diagenetic changes for the Tournaisian and Visean dolomites based on the application of data from cathodolumi...

If we create intelligent automated systems, decision support systems, expert systems, and in general knowledge-based systems then the development of the inference mechanism is very important. This mechanism of inference makes it possible to carry out reasoning on the available knowledge and data, to develop recommendations and decisions, to make their justifications and explanations. In this paper, a model of inference in the form of a bipartite graph is considered. The elements of the graph correspond to clauses,...

It is known that clastic material originated as a result of the transformation and translocation of rocks and minerals is the major constituent element of soil. Its genesis and petro-chemical composition essentially determines the formation of the soil of some or other taxon. The field and laboratory studies accomplished by us showed that soil-forming rocks in Interior Mountainous Ajara are andesite and andesite-basalt elluviums with intense magmatic instructive fracturing with various mechanisms and directions of...

The article deals with the problem of ownership of lands necessary for the operation of SHP by different entities. Several variants of solutions leading to the settlement of ownership relations to immovable property were elaborated. To ensure access, it was necessary to propose a range of service. The non-standard assessment also included solving problems related to the valuation of a flat in a small hydroelectric power plant, pricing and runoff and other engineering structures related to the hydroelectric power p...

Landslides are mass movement processes with severe consequences on the environment and human communities, and their identification and mapping is an important step in analyzing, evaluating and managing their potential risk. The results obtained in identifying areas of landslide activity may vary depending on the data sources used. The present paper is testing the landslides inventory at the scale of a commune in the Moldavian Plateau, Eastern Romania, using two different data sources: orthorectified images (2010-2...

In the environment are present heavy metals such as Cu2+ and Pb2+. Metal-processing industries, mineral processing, the manufacturers of inorganic products and large scale coal users, such as public utilities are the major sources of heavy metal pollution. These heavy metals are toxic, are non-biodegradable, and they pose potentially lethal risks at high levels. Chemosorption is emerging as a potential alternative to the existing conventional technologies for the removal and/or recovery of heavy metal ions from aq...

Among the restoration works in Northeast Romania, one can distinguish architect Ioana Grigorescu (1914 ? 2006). She was employed at Department for Historical Monuments and she designed inside existing buildings, spaces dedicated for the museum purposes as interpretation centers. Her work team used experience acquired during previous exhibitions spaces where the expressiveness of folk architecture forms where implemented. This creative architect conducted the restoration works of 17th and 18th century buildings, am...