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Directional couplers can divide the input power between its outputs in different proportions. This is due to the ratio of wave resistances between two pairs of quarter-wave segments. Due to the fact that at frequencies of 2 GHz and lower couplers are also actively used, it is necessary to take care that their dimensions satisfy the radio system where they will be installed. Due to the fact that it is not always possible was investigated miniaturization as an opportunity to reduce the area occupied by the branch wh...

A new mineralogical application for mobile phones and tablets was created named MINS (Mineral Identifier for Non-Specialists). Android Studio was employed in order to implement it in Java for Android devices and is compatible with versions starting from 4.0 (Ice Cream Sandwich). MINS is an application for macroscopic identification of the most common minerals (about 99%) that exist on the upper crust of the earth. The user has the choice of identifying a mineral or to see a list with the most common minerals. In t...

The main ways that are used to solve problems and create mechanisms for protecting information are generally considered to be: technical devices, the whole set of which is divided into: physical and hardware - and software - programs designed to perform actions aimed at ensuring the protection of information. As a result of the development of computer security and information technologies, experts have concluded that the use of any one of the above methods will not provide reliable information protection. The comp...

The municipal solid waste landfill in Tychy, southern Poland consists of three sites, the old one, closed in 1994, and two others still being in use. The old part of the landfill has neither any bottom liner nor any leachate collection and treatment system. Moreover, the bottom of the closed site in the northern part is continuously above the groundwater table, therefore, pollution can easily release into groundwater causing deterioration of groundwater quality and the nearby river nearby. In order to assess the i...

Modeling using artificial neural networks (ANNs) is used in most fields of production. An approach to modeling the dimensional changes in some iron-based powder metallurgy (PM) parts during the sintering process is given. The proposed model used is a multilayer neural network with a backpropagation learning algorithm. This type of neural network model gave the best results in the process of modeling. The specimens used in this study are prealloyed iron-based powders. The particle size of the powders is ranging fro...

The necessity for an integrated geographical approach to the study and modeling of ground-water dynamics in river floodplains is substantiated in the article. A preliminary and simplified classification of the types of annual ground and surface water level dynamics is proposed, which can serve as a basis for the differentiation of intrazonal floodplain landscapes. Thus differentiation is a scientific problem. In landscapes characterizing of the floodplains a descriptive approach prevails, and there are no quantita...

Aquatic ecosystems of the Arctic are very sensitive to the climate change. Thermic processes inside and around water objects (lakes, rivers, wetlands) affected by endo- and exogenous factors and lead to talik formation and geoprocesses interaction and turnover. Hydrological and geophysical investigation in the Lena River delta have been carried out in spring and summer 2016-2018. Sublake and subriver taliks georadar and electrical resistivity tomography data were obtained in a field with following hydrological and...

The resistivity of reservoir rocks varies in radial direction from Rxo (resistivity of the flushed zone) to Rt (uninvaded zone resistivity). This variation is due to different content in mud filtration, formation water and hydrocarbons from the well wall to the uninvaded zone. The penetration of the mud filter in the collector and the change of the saturation states depend on the properties of the drilling fluid as well as on properties of the collector (porosity, permeability). Electric logs devices measure an ap...

The aim of this research was to determine the global horizontal irradiation (GHI) for Istria and Kvarner, two western regions in the Republic of Croatia with the GRASS GIS r.sun module and to compare it with the values of solar irradiation obtained from satellite images and ground measurements. Since the results obtained from the r.sun module have no quality control, the accuracy assessment was made on ground solar irradiation measurements obtained from Baseline Surface Radiation Network stations (BSRN). BSRN is a...

Air temperature influences a variety of environmental processes, having a significant impact on the conditions of living of humans and other life forms. The Brazilian Northeast is a region that comprises a diversity of ecosystems, but it is most known as a semi-arid area characterized by severe environmental conditions. This work proposes to model air temperature in Brazilian Northeast to evaluate changing patterns between 2000 and 2017 using two interpolation techniques and comparing them. Monthly average tempera...

In recent years there has been a renewed interest in utilitarian cycling due to its recognized potential in the reduction of energy consumption and pollution in the cities. BikeBike-sharing systems generate a large amount of data which can be used to improve the systems themselves, or to improve the body of knowledge on urban mobility. The open data automatically generated by the Brussel's bike bike-sharing system (Villo) is explored through spatial regression models of the number of bicycle trips at stations. The...

This article reveals main methodological approaches, which allow to construct the adequate mathematical models that describe the effective condition of the social, ecological and economic components of development of the object, system-enterprise, territory, country etc. from the perspective of synergetics. Main ideas of research about the complex socio-economic and ecological systems that are based on synergetic approach are formulated. Characteristics, factors of functioning of complex socioeconomic and ecologic...

Horizon control in underground coal mining is still largely based on the knowledge and experience of a human operator, while many other operations run fully automated in mines nowadays. Several control strategies have been developed for automatic horizon control in underground coal mines, but none of them worked satisfactorily for a long distance up to now, even if the used sensors execute their intended task already and were improved continuously. However, the behaviour of the mining system itself, especially the...

The research was carried out in Tata Valley watershed, Dambovita region, Romania, which is a tributary of the Ialomita river. The objectives of this study were to estimate the annual soil loss by applying remote sensing data and the main data for the Tata Valley watershed and obtain a spatial representation of the results using GIS techniques. The method used to determine the soil erosivity and total eroded soil quantity in Tata Valley watershed, is the RUSLE + GIS technique, adapted to the specific conditions of ...

The characteristic of modern landscapes of the Kerch Peninsula as geologic systems in which natural and economic subsystems are inseparably connected is presented in the article. The component structure of the landscapes of the Kerch Peninsula (geological structure, relief, climate, water, soil, flora and fauna) was analysed using constructed thematic maps. The complex structure of the landscapes of the Peninsula is presented, with the indication of landscape levels, landscape zones, landscape areas. The descripti...

The conventional method of power generation is the main source of power today. With the changes in modern electronics, the uses of alternative power generation options become more and more viable. Series compensation has been successfully utilized for many years in electric power networks. With series compensation, it is possible to increase the transfer capability of existing power transmission systems at a lower investment cost and with a shorter installation time compared to the building of new, additional line...

Relevance of results. Experts note that growth of number of waste in Russia goes quicker, than GDP growth, so during the period from 2006 to 2012 the number of waste increased from 3, 5 billion tons to 5 billion tons. Constantly increasing volumes of waste cause need of elimination of their harmful effects on the environment. The main of the direction of the solution of this task is the organization of use, processing and also waste disposal. In this regard there is a problem of the choice of the most expedient de...

Corrosion represents a major problem in the flow assurance for the oil and gas industry. Carbon steel has been extensively used in oil and gas industry due to its cost-effectiveness, availability, strength, high durability and ductility. However, one of the biggest disadvantages of steel is highly susceptible to corrosion in the aggressive environments. Most of corrosion inhibitors are toxic, non-biodegradable and non-eco-friendly in nature, thus development of inhibitors based on natural resources are needed. In ...

There is old-established avowed demand of determination of ecologically proved limits of anthropogenic impact at natural ecosystems. Preservation of fresh waterbodies and streams ecosystems is very essential problem, because the fresh water more and more becomes one of the most important strategic resources. Of course, sea ecosystems are also needed in protection owing to their role in the biological resources maintenance. A monitoring system includes complex of different hardware and software, which must ensure f...

Monitoring short temporal changes in intra-urban vegetation areas will become very important as the proportion of urban areas continue to increase. Intra-urban variations in vegetation abundance influence environmental conditions by selective reflection and absorption of solar radiation and by sequestration of pollutants. This research investigates the hypothesis that it should be possible to use easily accessible multispectral Landsat 8 images to track intra-urban vegetation, and obtaining sufficient quality info...

Water level, electrical conductivity, dissolved oxygen, oxidation-reduction potential and pH of Suceava River were monitored in 2018 and 2019 in order to assess the upstream-downstream evolution of these parameters and the impact of Suceava City on this river that divides its built area. The measurements were done automatically every hour with two AquaTROLL 500 instruments. This study focuses on analyzing distinct time intervals with typical and atypical fluctuations of the selected parameters as well as on identi...

The dams along with the accumulation lakes formed behind them are man-made water reservoirs for efficient use of the planet's water resources. The dams are big hydrotechnical structures in particular represents construction with very long duration of life and achieve their financial efforts imply particularly important. Over time, changes of external environmental factors may occur, which will influence the behavior of the dam. The environmentally aggressive conditions can be changed in relation to the material fr...

This paper discusses the preliminary results from the monitoring project of two contaminated sites (Predajna I and II) related to the former petrochemical industry (refinery) in the central Slovakia, and the waste generated by this industry. Waste product arising from this process are acid tars called ?gudron? in the Slovakian terminology. Due to the nature of deposited waste with a very variable composition (sulphuric acid, sulfonates, chlorides, mineral oils, etc.), both sites pose risk, or even potential threat...

Sediment transport in rivers is posing a hazard to infrastructures and cities built along the river courses, especially in mountain areas. Awareness about this topic raised in the last decade and even the European Flood Directive in 2007 stated that particular attention should be devoted to ?areas where floods with a high content of transported sediments and debris floods can occur?. Authors are monitoring sediment transport in a 24km2 basin in Alps, Northern Italy, since 2016. This stream was surveyed multiple ti...

The connection between tectonic conditions of development and geomorphological features of the coast of Kherson region was analyzed in the relevant article. Geomorphological features of coastal zone were considered from the position of block structure of Karkinit-Sivash system of troughs. For the first time the attention was referred to the tectonic dependence of morphological and morphostructural features of coastal zone of research region. It was established that the mosaic of natural environment is typical feat...

Mud volcanoes occur both on land and oceans, but their occurrence is generally known on limited areas. Many of the European mud volcanoes structures are known from Romania, where their number exceeds 40. The most impressive and famous of the Romanian mud volcanoes are situated near the Buzau town, at Berca, in the Romanian Carpathian bend area. Other Romanian mud volcanoes are situated in the Transylvanian Basin and in the SW part of the country (Banat region). This paper presents the geological setting, including...

Environmental restrictions get every day more demanding; therefore, energy policies focus on reducing greenhouse gas emissions, setting clear targets relative to the renewable energy contribution in meeting electricity demand. Thus, the global tendency towards fossil fuel replacement by renewable energy sources (RES) is progressively sharpening. Sustainability of power systems with high renewable energy penetration rates is a topic of major interest, especially considering the intermittency of RES production and t...

Wine has always been a valued commodity, from ancient civilizations, up to current times, both from a quantitative point of view, and a qualitative one. Humans have been cultivating vineyards for thousands of years, with differential success. This has always been dependent on several, mostly natural factors. Even the most resilient varieties of grape vines require some specific conditions to optimally grow, such as climatic factors (including specific growing temperatures, precipitation, sun exposure, number of an...

When preparing the field for industrial operation, it is necessary to build a conceptual model that reflects the internal structure of the objects under study. Conceptual modeling, in turn, is based on the methods of system analysis and interpretation of all available geological, geophysical and seismic information in the study area using various types of system analysis, which allows to predict changes in lithology and filtration-capacitive properties of rocks, as well as assess the reserves of the field. The con...

It is known that one of the methods for purifying gas fraction from hydrogen sulfide is amine treatment. Various types of amines are used to remove hydrogen sulphide, carbon dioxide and carbon dioxide from petroleum gases. The choice of specific amine depends on the needs of the process. Mono-ethanolamine (MEA) (C2H4OH) NH2 and diethanolamine (DEA) (C2H4OH) 2NH are commonly used. Both are ammonia derivatives. To develop recommendations on the choice of material from which to make equipment for amine plants, compar...

New ways in the field of extinguishing by solid extinguishing is aerosol fire fighting originally developed in the 1970s by the Russian space research agency called ?SOJUZ?. More significant development in the aerosol fire extinguishers usage occured in Europe in the 1990s. Carbon as basic element of organic compounds with two allotropic modifications can be found in various modifications like diamond and graphite. Fullerenes as the third modification was discovered in 1985. Detailed analytical researches have fou...

The process of mixed oxide coatings forming on a high-silicon aluminum alloy in the cobalt-containing pyrophosphate electrolyte by the plasma-electrolytic oxidizing (PEO) method is studied. It was shown that AL25 chemical composition heterogeneity causes the consumption of part of the anode current to homogenize the treated surface, which is reflected in minimizing the content of doping components at the initial processing stage. It was established the growth of mixed oxides Al2O3·CoxOy relative mass to be a funct...

Formation and development of the centralized national system of qualifications has become a burning issue in the Russian Federation. This is due to a number of essential reasons, which include globalization of the economy, specifying of universal competencies being in demand in the labor market, the existing gap between university curricula and professional standards requirements. The article aims at presenting a review of the relationship between the Russian national qualifications system, its evaluation of labor...

In general, analogues are examples that demonstrate one or more key aspects of some concept or technology that is being developed. By studying such analogues, we can improve our understanding of both the technical concept and its application - in this case, large-scale geological CO2 storage involving one or more Mt of CO2. Two main types of CO2 occurrence are found in nature: ?Accumulations that have remained in place for thousands to millions of years with noevidence of leakage (Ciocaia site); and ?Accumulations...

Natural gas hydrate are solid compounds formed from water (host) and gas molecules (guest) at relatively high pressure and low temperatures. They are considered as a potential alternative energy source because of their high energy density, potential carbon-neutral nature and wide existence, both in permafrost and ocean seabeds. The most developed strategies for exploiting hydrate deposits are depressurization, thermal stimulation, chemical inhibitors and CO2 replacement. In particular, chemical inhibitors promote ...

The author developed a thermoelectrical model of Solar system planets? magnetic fields and calculated Saturn?s magnetic field with its help. Radially directed thermoelectrical currents of the electroconductive layers of the planet are the essence of that model. The movement of those currents are determined by the intensity if the magnetic field, which is caused by the planetary thermogradient, e.g. the difference of temperature between the planet center and its outer shells of the electroconductive layers. The cal...

The interruptions in electrical energy supply are unplanned events, determined by faults of the distribution network?s components, lightning strikes or unauthorized interventions in the distribution networks. Insulation faults, occurring in medium voltage networks, produce transient regimens with overvoltages/ overcurrents of very high values, produce large requests of network, switching equipments, generators and telecommunication systems. Because of this, the neutral point of the secondary transformer in the med...

Synbiotics are defined as a composition of probiotics and prebiotics with synergistic reinforcing effects. In practice, only growth stimulation is often took into account when justifying the effectiveness of a synbiotic composition. However, the effect of prebiotics to the interaction of probiotic and pathogenic bacteria during co-culture fermentation was examined in a range of researches. The influence of commercial prebiotics on the ability of probiotics (bifidobacteria and lactobacilli) to suppress the growth o...

Inorganic arsenic is in very small concentrations a common constituent of surface and groundwater. However, its increased concentration may pose a significant risk to human health in connection with its carcinogenicity (a proven human carcinogen). Therefore, it is necessary to address the reduction of its concentration in drinking water using the most efficient and financially undemanding techniques. The paper analyzes current and new trends in the field of removal of arsenic from drinking water. It focuses mainly...

Treating depression is a complex process, which includes medical treatment and also psychotherapeutic approach. These two approaches are working together. There is a large scale of known treatments for depressive disorders, which had been developed since the 1950s and the therapeutic effectiveness and patient tolerance were assessed through generations. Among the studied variants, anorganic products had been Among the studied variants, anorganic products had been Among the studied variants, anorganic products had ...

Like other European maritime countries, Romania is trying to respond appropriately and to adjust its policies to the current challenges and geopolitical developments. Among the decisive steps made in this regard, is the redefining of its actual maritime space security. A new tool, namely created, tested and commissioned in this regard, within the experimental-demonstrative research project ?Implementation of a geophysical investigation and monitoring tool for Romanian maritime space security ? MAR-S? is a GIS-data...

D-glucose simultaneous catalytic hydro condensation with methylamine can beconsidered a promising way of methylglucamine synthesis. Amines such asmethylamine are reacted with materials such as reducing sugars in hydroxy solventssuch as methanol to prepare N-alkyl polyhydroxy amines. Accordingly, glucose isreacted with methylamine and the resulting adduct is hydrogenated to yield N-methylglucamine. The production of N-methylglucamine as early as 1935 was patentedby American scientists Robert B. Flint and Paul L. Sa...

The main goal of the presented research was to compare the nitrogen use efficiency (NUE) of winter wheat and white clover mixed cropping system (MC) with sole cropping system of winter wheat (SC). The above goal was investigated using lysimetric experiment carried out for two vegetation periods (2012?2014). The experiment consisted of seven variants with different cropping system and level of fertilization: five variants were grown as MC (0 kg N/ha; 112 kg N/ha; 112 kg N/ha + 1.25 L of humic acids/ha; 70 kg N + 0....

Recently, Horava-Lifshitz proposed the theory of quantum gravity, which takes into account the degree of renormalizability in the ultraviolet. This was achieved by anisotropic scaling between space and time, and, therefore, it violates the Lorentz invariance in the ultraviolet range. The infrared limit of a theory reproduces the general theory of relativity for a particular choice of parameter, namely . Lorentz symmetry breaking is performed by preferred foliation of threedimensional space-like hypersurfaces, whic...

This paper presents a cross-sectional analysis of the noise on the navigation bridge of a commercial ship that navigates a section of the Romanian Danube segment. This room is important because here are given all the commands for safe navigation so the conditions inside it must be of the highest quality. Determinations were carried out on the pusher, between Braila and Calarasi, in February 2018, in very difficult weather conditions. The noise was measured with BlueSolo 01dB sonometers. These were placed on the na...

Occupational noise exposure in the workplace is linked with a range of negative effects on human health. Many researchers agree that the noise-induced hearing loss is the second most common form of sensorineural hearing deficit, after the illness of age-related hearing loss. An extended exposure to occupational noise can generates devastating disability that is potentially 100% completely preventable. The hearing deficit begins at the higher frequencies and it develops gradually as a result of chronic exposure to ...

The paper describes the use of methods of visualization and non-destructive investigation of spatial distribution of changes in the structure of the monitored material, which was a cement composite with admixture of blast furnace slag. The test specimens in the shape of the cylinders with a diameter of 24mm and a height of 25mm were placed in an aggressive sulfate environment represented by bacteria of the microorganism Acidithiobacillus thiooxidans for 6 months. To investigate the spatial distribution and the deg...

Adjustment of compositions and processing techniques, mainly ? firing conditions, has been a key route for ceramics performance improvement. The present research addresses sintering process of alumina ceramics with an additive in system that was studied by non-isothermal method. Experimental samples shaped as cylinders 25 ? 6 mm in size were obtained and sintered by consequtive firings in air at heating rates q1 = 1,0 and q2 = 3,0 °?/min without curing and quenched in air. Linear shrinkage (? = ??/?, hereon ? ?) a...

The northern polar region is under the influence of cold temperatures, increasing the effect of snow Arctic aquatic ecosystems affected by climate warming as well as human impact. Different scenarios of climate change show a possibility of temperature increase on 1-2?C and more depending of CO2 emission accounting. All global models give significant valuation to the Arctic exactly. Aquatic ecosystems take several parameters that allow to save their inner stable state and resilience. According to water physical par...

Novel micro and nanostructured bioemulsions were created by innovative technologies based on fibrillar cellulose/titanium dioxide/(surfactants mixture: dodecandioyl-diglycine and sucrose diester/ethanol/water, for improved surface properties development with applications in leather industry. The high potential of using cellulose as a material for various applications: in membrane technologies for pollutant absorption, in pharmacy, etc. opens the way to obtaining new added value materials (hybrid micro and nanocomp...