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Black Sea is one of the largest inland seas in the world and is vulnerable to land ? based pollution pressure from its littoral area that causes the degradation of the aquatic ecosystems through eutrophication. Sometimes were recorded at the Romanian littoral a macroalgae mass development, especially by the group green macro-algae, Ulva, Enteromorpha and Cladophora species which are present in associations succeeding in all the year. A comparative study of waste algal biomass microbial charge was done in order to ...

The article deals with the degradation of cement beams containing polypropylene and polyvinyl alcohol fibres. Nowadays it is developed high-quality concrete that contains a minimum of reinforcement or all it is replace by micro fibres. Microscopic examination of fiber breakage and changes at fiber-matrix interface was investigated in this paper. The cement beams were stored in an aggressive environment of 3% NaCl, 5% NaOH and 5% H2SO4 for 28 days (CSN P CEN / TS 12390-11). Mechanical parameters and changes of fibr...

Gypsum paste was subjected to the temperatures up to 1000 В°C and its microstructure was investigated by SEM microscopy. The volume and mass changes were also measured and the bulk density, porosity and residual strength were determined. After heating to the 1000 В°C the structure of paste changed substantially, as can be seen in the micrographs. The structure of heated material is denser and the anhydrite crystals are bigger. The volume of the samples decreased more than 50%. The bulk density increased by 20%, wh...

It takes adequate IT tools to implement and perform information processes in an organisation. Such tools can be developed by means of popular and frequently used programs, such as spreadsheets. The tools created in spreadsheets may be consistent with the author?s signature concept of Microtools Based on the Relational Data Model (MiRel). This concept delivers specific solutions intended for representation of identified entities and ensures integrity of both data and the assumed reports and collations assumed to be...

With regard to the ever-increasing road traffic density, the demands on the transport infrastructure are also increasing, or more precisely on its quality. For this reason, even a slightly damaged road surface is often considered unsatisfactory and its reconstruction is necessary. Increasing the amount of heavy and especially overloaded vehicles has a significant impact on the life of the roads, as they cause permanent deformation of the surface layers of the road. A further significant influence is represented by...

In the East of the Russian plate oil-gas occurrences in Bashkortostan, Perm region and Udmurtia were revealed in the Vendian-Riphean sedimentary deposits. Industrial oil inflows have been obtained in a number of areas. Possible perspective intervals are associated with great depths, in particular, with the deposits of the lower Riphean. The deposits of the Lower Riphean in the territory of Bashkortostan were discovered on the Eastern-Askinskaya area. The results of a study of the material composition of rocks show...

The crystalline basement of the Tatar arch located in the eastern part of the East European Platform (Russia) is composed of the metamorphic rocks of different composition and genesis. The Tatar arch consists of two blocks of the basement. The North Tatar and the South Tatar blocks are separated by a faults system. The South Tatar arch is a granite-gneiss core of the basement. It is composed of Archaean-Proterozoic metamorphic complexes of rocks (granite-gneisses, gneisses, migmatites and granulite-gneisses). The ...

Medvezhye gas field is the oldest known one in Western Siberia and unique because of its values. At the present time most of Cenomanian deposits are exhausted. Senonian sediments, which are such nontraditional reservoirs as clayey opokas, opoka-like clays and opokas, are considered as a source of resource potential compensation. Objects of the study are 34 core samples taken from two drill holes and belonging to the lower part of Berezovskaya suite. Geochemical and mineralogical features of the rocks were studied ...

The paper presents the results of the research of ore mineralization in quartz, quartz-sulfide, quartz-carbonate-barite, carbonate-barite veins of Dyvok ore occurence. The object of the research is located in the South-East of The Sakha Republic (Yakutia) and is a part of the Stanovoy gold-bearing region. The gold mineralization was found out to belong to gold-quartz-sulfide type, to relate to the stock of Cretaceous granite-porphyry and to be located in the K-feldspar-quartz metasomatites, beresitization and arki...

The Kuznetsk Alatau ridge represents a NW segment of the Altai-Sayan folded belt (ASFB) and is considered as a Caledonian collisional system. The ophiolites from the northern slope of this ridge are the most representative fragments of suboceanic crust. This work presents the results of a study of the mineralogical composition of metabasites from ophiolite paragenesis of the Severnaya, Zelenaya, Barkhatnaya mountains and Semenovsky massif. The samples from the gabbroid and subvolcanic complexes were selected and s...

Synthesis gas for an electrochemical generator was produced in a thermochemical reactor with autothermal air conversion of methane (natural gas). Based on thermal balances of the reactor, a battery of SOFCs and a boiler-utilizer (BU) for heating primary and secondary air, cathodic air and methane, the following parameters were calculated: temperature at the anode, EMF of the fuel cell, electrical efficiency (gross) of the electrochemical generator, portion of hydrogen oxidized at the SOFC?s anode and specific cons...

Microstrip devices have found wide application in various fields of radio engineering. However, such devices are made on dielectric substrates from various materials - glass,mica, ceramics, etc. In the process of manufacturing microstrip devices, it is possible to use, as etching method, this removal of excess copper coating, and removal of copper coating with special equipment, for example a milling machine . As a result, at various stages of manufacturing, material waste remains in large quantities, a solution f...

Miniaturization of microwave devices, such as directional couplers, filters, switches, etc., is an important practical problem due to the trend of integration of portable and small high-frequency electronics. In this paper, we consider the technology of developing a miniature microstrip device, which can be used in small space satellites and other aircraft, for which mass and dimensions are important. Modeling was carried out in the program for electrodynamics analysis of radio electronic devices in the NIAWR Desi...

The aim of the project is to determine the optimum geometry and different kinds of nozzles location on the drilling tools face. The optimum geometry and its proper arrangement will allow the maximum use of specific mechanical energy drilling through its reduction and minimizing pressure losses to overcome flow resistance in the nozzles of a drill bit. In their previous work, the authors showed that hydraulic power is a very important aspect, affecting the loss of pressure at the bottom of a borehole. It has been s...

Many simplifications are often made, in calculating of eigenmodes and eigenvalues of stuctures. The mass of a structure is distributed throughout the structure. However, in most cases, mass can be considered concentrated in the nodes of the structure. The procedure consists in concentrating the mass of the elements at each end thereof, followed by the summation of the mass of the elements that compete in the corresponding nodes. Generally, rotating mass components have a minor influence on the dynamic response of ...

Influences of earthquakes on nuclear power plants and their parts are studied in frame of nuclear safety. In the past, the authors have dealt with the effects of earthquakes and vibrations in the primary circuit. However, it cannot be omitted that the seismic influences can show up also on the secondary circuit. Turbines installed in secondary circuits of nuclear power plants are big and heavy machines. For example the turbine installed in JETE (Temel?n Nuclear Power Station ? Czech Republic) generates 1003MWe. It...

The goal of this project was to create a detailed model of the Aral Sea sedimentary cycles. Modern methods of image processing and wavelet analysis were used to reveal the nature of lamination and determine the average and interval sedimentation rates. The results obtained were then compared with those from the radiocarbon dating. The images used in this project are photographs of core (sediment) samples taken with hollow plastic tubes. The samples were removed from the tubes by cutting them in half lengthwise, an...

In the framework of this study, the features of the competencies in the modern education system are highlighted in the conditions of increased production of information resources, knowledge and their use in innovative products. The key role of research competencies as a way of generating innovative solutions in comparison with alternative approaches to the organization of innovative processes is shown. Models for evaluating innovation processes in terms of the growth rates of production of modern products, increas...

Lately, high penetration of intermittent renewable energy sources into power systems requires, besides efficient technologies employment, developing adequate control strategies to improve their performance. Given that their operation flexibility is constrained by short timeframe of foresight, energy storage systems represent an attractive solution that can mitigate the natural variability of renewable power plants electricity output, providing therefore enhanced quality of supply. The nonlinearity and uncertainty ...

The article deals with the modeling of the structure of the e-learning website with the possibility of changing the user interface in accordance with the information needs of users. The most popular content management systems (CMS) and learning management systems (LMS) have many necessary features, including using an uncluttered modern editable interface and configurable LMS front page of the e-learning course. But, as a rule, these systems do not contain the component that would be responsible for the ability to ...

When documenting of existing bridges, object geometry knowledge is the highest importance. Complex construction documentation usually has limited spatial representation of the object, based on a limited number of basic forms of modeling, represented by edges, corners, planes and volume elements of the real object, and depending on the purpose, the model results must match within a certain accuracy with real object. Rehabilitation of bridges also involves the realization of detailed plans in situations where they n...

Granular sludge aerobic technology (AGS) has been extensively studied in recent years because of its advantages compared to activated sludge technology. Currently, this technology is implemented in SBR (sequential batch bioreactor) configuration. An experimental model bioreactor was designed for adapting the AGS technology to continuous flow conditions. It consists of a rectangular shape bioreactor, an area for pre-settling and recycling of granules, followed by a settling tank. This configuration is more suitable...

Methods of deductive inference that are various modifications of the principle of resolutions are quite effective in logic. The results and justifications for the fuzzy conclusion of the resolution type are widespread in the predicate calculus. The existing models of the resolution inference are effective, and also quite simple and convenient, for conventional reasoning under incomplete information and for automatic processing of uncertain knowledge in interactive systems. However, in such models the set of genera...

The anaerobic fermentation of biomass in methane-tank during the biogas production is considered. The process of individual bubbles lifting upwards and its simultaneous interaction with solid particles with mixing of the nascent substrate is analyzed. The forces acting on the bubble are given and a differential equation is developed that characterizes the biogas bubble movement in the organic mass substrate. The mathematical dependence of the flooding rate of the biogas bubble is developed and an example of solvin...

Hillslopes comprise the greater part of the landscape and as an integral part of drainage basins; they provide water and sediment to water courses. Also, hillslopes are frequently used in agriculture. Soil erosion caused by water is a natural phenomenon, but the negative effects are accentuated by human interventions in the landscape. Soil erosion and nutrient loss are detrimental to agricultural products, food security, and the sustainability of ecosystem functioning. In recent decades, the increased using of che...

The article presents a way of identifying and modeling sound features in an urbanized environment. The subject of article is focused on the problem of noise pollution modeling coming from moving technical objects, i.e. vehicles that are potential sources of noise. In this case, the vehicles are treated as multi-source acoustic energy emission objects. The proposed approach assumes the occurrence of variable relations in the system: source-path propagation-receiver. In the presented method the information carrier i...

The article presents the proposition of numerical simulation of the sedimentation process in sedimentation devices, including the method of defining and validating the numerical model of the suspension. The proposal includes a proposal to define a suspension in numerical simulation as a multiphase system with a polydisperse grain composition. The article contains information on the method of defining a multi-phase system based on grain composition of a suspension. A proposal for verification of the numerical model...

The authors propose a model of nonlinear interaction of social network agents, which is based on a matrix generalization of the known one-dimensional logistic mapping. Similar models have not been considered previously and have not been investigated numerically. Despite the relative simplicity of the proposed non-linear model, in the course of numerical experiments, various modes of agent behavior were observed. Namely, one of the agents hesitated in making a certain decision, others were able to "agree" (came to ...

Paper focused on extension of usage of the AutoID model of transport system in laboratory. Transport model is equipped by complex AutoID system based on RFID and magnetic sensors. They are used to gather information from transport processes. The aim of solution presented in paper is to describe data flows in this physical model and to design representation of data flows and processing in simulation system Witness. This kind of model can better present behavior of data background to students and make them better un...

At the age of an increasing demand for energy we reach to an ever wider range of substances giving a possibility of its generation. A constant need for energy supplies is so strong that we are not prevented by the danger related to the storage or transport of such substances. Although we try to eliminate any risks, even a small human error may contribute to a tragedy. In the case of substantial and sudden depressurization it is impossible to conduct in situ tests at a large scale. An attempt at conducting an in si...

The finite-difference method is used to compute small local deformation of the rock slope instability Alpe di Roscioro, Switzerland. This retrogressively unstable mass failed multiply, with last large catastrophic event in 2012, when approximately 210 000 cubic meters of rock had collapsed towards Preonzo village. The remaining mass has been studied and monitored by passive seismic methods and exhibits strong directional spectral amplification. One of the monitoring seismometer detects many micro-deformations and ...

The priority of the manufacturers and production companies is to improve product quality and reduce the cost of manufacturing. The resulting quality is often strongly influenced by the heat treatment of the product. The creation and implementation of mathematical and simulation models is an effective tool for studying of the thermal processes. We can use the simulation models at the construction of new but also in the reconstruction of existing thermal aggregates. In addition, from simulation studies, we can choos...

The flow of gases through porous media is a common physical phenomenon occurring not only in the natural environment but also in a number of technical applications, including the industry. The flow of gases through rock porous media takes place during exploitation of numerous energy resources ? not only during the excavation of hard coal (the flow of a gas mixture through goaf with caving) but also in the course of exploiting crude oil and natural gas (the flow through shale rocks). The issue of gases flowing thro...

Green roofs represent one of the most diffused and representative Low Impact Development techniques (LID). Green roofs consist of a number of layers, including a vegetation layer, a lightweight soil medium, a drainage layer and an impermeable membrane. Recent studies have confirmed the benefits of green roofs. Green roofs are able to retain water, reduce peak flow, improve biodiversity and mitigate heat island. Although the benefits are evident, the transition from traditional urban drainage systems to the sustain...

Permeable pavements are among the most diffused Low Impact Development techniques (LID). Several studies have confirmed the optimal performance of permeable pavements in terms of peak reduction and water retention. Furthermore, permeable pavements have proven to reduce pollutant load in runoff water. Although the benefits are evident, the transition from traditional urban drainage systems to the sustainable ones is very slow. The lack of accurate modelling tools represents a key limiting factor in the diffusion of...

One of the major assumptions of the so-called Ecodistrict is Scharnhauser Park, Ostfildern in Germany, it is an interesting example that mostly consists of a newly created urban fabric. Many scientific publications focus on technical aspects related to the protection of the environment and natural resources, which, in fact, in this type of projects are achieved by the applied recycling technologies and other technological solutions. Energy efficiency is not directly translated into the quality of living and the qu...

The paper describes a mathematical model of the global crisis influencing the world economy. The model is based on four conceptual positions of modeling: the level of economic development of the global economy is estimated by the system of endogenous variables; there is the interdependence of endogenous variables; there is a process background for the endogenous variables; there are certain harbingers of the crisis determined for a specific endogenous index. The model is presented as a system of three interdepende...

Power system components can be loaded up to their thermal limits and power transfers resulting from fast varying load patterns are leading to an increased congestion. The conventional energy sources combined with the trend of use of renewable generation will make the future grid more resourceful and responsive, more intelligent and smarter for its users. Central power stations have lower efficiency, high polluting stations affects the environment. In order to overcome these problems structural changes are needed i...

The paper analyzes the use and production of modern lighting columns made of aluminum for street lighting. The modern process of manufacturing conical pipes by means of the box rolling method on a special laboratory mill built for this purpose is presented. The study performed the most important parameters for seamless conical aluminum tubes along the entire length of cylindrical tubes. It has been shown that the use of modern street LED lighting mounted on light cone-shaped lighting poles is cheaper, more ecologi...

Natural gas and oil have been unquestionably the most important energy resources in the world for years. Unfortunately, the occurrence of oil-based regions does not coincide with the main areas of oil and gas consumption. Therefore, it is necessary to transport hydrocarbons over very long distances. Sometimes thousands of kilometers. Laying pipelines is an extremely costly and logistically difficult engineering project. The basic methods of building gas pipelines include laying them in an open excavation. Sometime...

Major genetic concepts currently existing in geology are based on the hypothesis of the Earth?s cold homogeneous accretion put forth in the mid-20th century. The data obtained in the last decades are in conflict with these concepts. It has been found that compositions, isotope ages and formation temperatures of the crustal and mantle rocks are interrelated according to the laws of magmatic differentiation. This indicates that the rocks formed as a result of fractionation of the global magma ocean. Chemical disequi...

Geophysical exploration, the necessary part of oil and gas exploration, generates more and more data, subject of processing. The most powerful super computer clusters are used by business and academic institutions. However, often it is necessary to have evaluation of the measured data shortly after measurements, even in the field. Modern computer architectures, namely Graphic Processing Units (GPUs) and Field Programmable Gates Arrays (FPGAs) provide a good basis for PC-based fast data processing, to have, say, su...

The article presents a combination of modern methods regarding the problem of sedimentation processes. Suspensions are widely present starting from exploiting processes, through processing of natural resources, metal casting and processing, chemical engineering, problems of supplying drinkable water, and to sanitary engineering and technological processes of water preservation. Processing of suspensions using sedimentation is commonly used in previously mentioned disciplines. It is usually made by clarification, d...

The integration of a building into the environment can be achieved both from the architectural point of view and from the point of view of the used building materials, thus remarking material used since ancient times, namely wood. Wood is an organic, sustainable, environmentally friendly material that can reduce carbon dioxide emissions Due to the latest environmental protection requirements, economic issues related to construction costs and architectural diversity, it has been necessary to develop technologies re...

Shoot cultures of the essential oil-bearing Artemisia alba Turra were established with the aim of the in vitro exploration of the biosynthetic potential and physiological behavior of the species. Plant growth regulators were applied in order to affect morphogenesis in vitro and to search for possible relations with secondary metabolites production of the plant. As a result of the applied treatments, two morphotypes of the in vitro cultured A. alba individuals were induced, based on the development of roots of the ...

Shoot cultures of the essential oil-bearing Artemisia alba Turra were established with the aim of the in vitro exploration of the biosynthetic potential and physiological behavior of the species. Plant growth regulators were applied in order to affect morphogenesis in vitro and to search for possible relations with secondary metabolites production of the plant. As a result of the applied treatments, two morphotypes of the in vitro cultured A. alba individuals were induced, based on the development of roots of the ...

Long-term research on the ownership structure of individual farms in rural areas has shown that these areas are characterized by a defective patchwork of private land ownership. The sizes of the patchwork may limit, and often even prevent, the programming of works on agricultural land. The development of an algorithm for identifying areas characterized by a strong concentration of a defective patchwork of land ownership allows the selection of these areas (groups of villages) where land replacement works should be...

The federal information system for providing state final certification and admission can be transformed from a tool of adherence to and compliance with the law in the sphere of admission to higher education programs as the basis for an automated information system for organizing a centralized competitive selection for Russian universities. The research shows that this system needs only a small modification in terms of expanding the list of stored information. At the same time, the technical capacity of the federal...

The paper is devoted to construction of the time efficient algorithm for solving the structural inverse gravimetry problem. The problem is in finding by known gravitational data multiple interfaces between layers with different constant densities. This problem is described by a nonlinear integral equation of the first kind; so, it is ill-posed. After discretization of the area and approximation of the integral operator, the problem is reduced to solving a system of nonlinear equations. An efficient method was cons...

The molecular characterization of Genetic diversity of ten bread wheat (Triticum aestivum L.) varieties was evaluated at the DNA level using 6 agronomic characters and 16 wheat microsatellites molecular markers (Simple Sequence Repeat-SSR). SSR bands were scored across all genotypes, for presence (1) or absence (0) and transformed into 0/1 binary matrix. A pair-wise similarity matrix was generated with the software NTSYS. The Polymorphism Information Content (PIC) ranged from 0.23 to 0.70 respectively for the prim...