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Co-operation of renewable energy sources (photovoltaic cells or micro-wind turbines) with 230V receivers, eg LED substitutions of traditional light sources, requires the conversion of low voltage direct current electricity to 230V AC. Various designs of DC/AC converters intended for island operation and synchronized with the power grid were tested. The Hioki 3196 energy quality analyzer was used for the study. The stand-alone systems are used in voltage converters of very simple solutions converting DC power to AC...

In Poland the fundamental energetic material for many years is hard coal. According to draft of energy policy such state will be maintained at least until year 2050. Therefore it is necessary to carry out researches and take actions in order to limit emission of harmful products associated with production and utilization of this mineral. Nowadays, pro-ecological activities, mainly focus on development and application of technology the purest processing of coal into thermal and electrical energy. However less atten...

Considering that the EUпїЅs long-term environmental sustainability objective is among the United Nations Millennium Development Goals, this article examines how European horizontal legislation promotes products with a low environmental impact throughout their lifecycle and the provision to consumers of accurate, non-misleading and scientifically accurate information on their environmental impact. The article aims to present the legal instruments developed at European Union level to promote high-performance environ...

In the paper, it is proposed to perform a comparative analysis of the strength and stability calculations for the VST-20000 stationary roof by using two methods. The first method would be the one of structural mechanics described in [1, 2], and the second one is a numerical method performed in the ANSYS software complex. The finite element model of the VST-20000 roof was used to calculate the stationary roof of the tank in ANSYS, which implements the finite element method. The tank computer model represents the sy...

EOR thermal processes involve both introducing of warm fluids in oil reservoirs through injection wells and also extraction of warm/cool fluids through production wells. A model that describes the process for heat transfer from the fluids flowing through the well at its contiguous environment, and the calculation of the temperature along the well can be used in various applications of heat transfer aspects, especially when the bottomhole equipment of the well doesnпїЅt allow measurement. This paper presents a mode...

The demands on university teachers of technical subjects are changing in the context of economic and political developments in society and opinions on the form, content, scope and mutual relation between professional activities to be carried on. A university is a place where pedagogy and andragogy overleap due to the fact that there are regular students as well as professionals taking a course of study aiming at extending their qualifications. A university teacher affects both of these groups, as a pedagogue and l...

Promoting sustainable use of groundwater based on reducing pollution and on preventing later pollution is a basic desideratum of the Water Law No. 107/1996 with later additions and alterations and of the Directive 60/2000/EC in the field of water issued by the European Parliament. Water resources are a source of normal economic development: they ensure nature balance and life continuity and this is why we need to rationally use them during both normal and crisis periods (e.g., drought). Ground waters are an ecolog...

Construction and Demolition (C&D) materials which consists mostly of concrete debris were deposited on landfills. The development of road network results in an increasing demand for building aggregates which are part of the road construction unbound subbase. For decrease of investment costs and prevention of spoiling natural resources, the C&D materials, such as fly ash, steel slag or recycled concrete aggregates (RCA), were applied as a subbase mix. Among many properties influencing the quality of road material, ...

Biguanide and its N-substitutes derivatives represent a difunctional compounds group known for their diversity therapeutical activities, such as antimalarial, antibacterial, disinfectant, antiviral, antihyperglycaemic agents and recently literature reports as analgesic and antidepressant drugs, selective agonistsпїЅ serotoninergics for the serotonin 5-HT3 receptors. In the last years the literature points out a large practical applications spectrum of the 4f metal complexes for their remarcable spectroscopy, optic...

Aromatic and medicinal plants are an important source of antimicrobial molecules, especially in volatile extracts. The genus Thymus is considered among the richest general in secondary metabolites. In this context, this work examines on the study of the extraction of the organic compound by steam soxlhet of a species endemic Thymus numidicus from Bouira. These naturalsпїЅ substances are recovered by differents solvents; aqueous, ethanolic, and methalonic. On the other hand, the determination of the antimicrobial a...

The article presents the study on the effect of thermal and acidic hydrolysis treatment on the antioxidant activity of humic acids. It clarifies the changes in macromolecule structure resulted from the variations in periphery/nucleus ratio. Using the differential-thermal analysis, kinetic parameters of humic acid thermal-oxidative destruction were determined. The studied samples of humic acids were divided into three groups: humic acids extracted from air-dried fen and terrestrial fuscum peat, humic acids subjecte...

This study presents functional and nutritional properties of the tomatoes (Solanum lycopersicum L), an ideal source for health promoting compounds. In this paper eleven cultivars of tomatoes were studied that were grown in greenhouses in Oltenia (Romania), which were differentiated between them by shape, size and colour of the fruit. For biochemical determinations, fruit samples were collected at physiological maturity. It was determined the content in soluble dry matter, total dry matter, vitamin C, content in ma...

Cruciferous vegetables are rich source of phytochemicals which play an important role as a health-protecting factor. These compounds and enzymatic systems may combat oxidative stress in the human body by maintaining a balance between oxidants and antioxidants. This is particularly important because under oxidative stress excessive formation of reactive oxygen species (ROS) can damage biomolecules, such as DNA, proteins, lipids and carbohydrates, and lead to numerous disease conditions. The enzyme superoxide dismut...

The global population of menopausal women is on the rise and expected to increase from 470 million in 1990 to 1.2 billion by the year 2030. Most of them suffer from postmenopausal symptoms, such as hot flushes, tender breasts, vaginal dryness, reduced bone mineral density, cognitive deterioration and neuropsychiatric disorders such as different mood disturbances and cognitive impairments including AlzheimerпїЅs disease (AD). Considering the wide use of complementary and alternative medications such as bioactive su...

Gridded climate data are valuable source of information that can be used in various fields of environmental studies. One of the example is dendroclimatological analysis, where climatic data are essential part of the study. These data are especially useful when there is a lack of weather station data for the study area, the available data are incomplete or their time span is insufficient. However the accuracy of gridded data can be sometimes questionable. In this study gridded data planned to use in dendroclimatolo...

Geotechnical monitoring aspects of construction activities in congested urban environment are discussed. Successful application of express methods, enabling mobile equipment use for soil tests is described. Case histories of such applications in Moscow historical downtown are given. Data, obtained by such monitoring, is analyzed, and a conclusion is drawn on the necessity to apply sparing technologies when construction operations are carried out in the vicinity of buildings in service. Development and redevelopmen...

The coal processing industry uses a various technology for the process control. Various devices and control systems there can be implemented. With the support of automation, the production of final product can be more effective. Modern control system requires an advanced control algorithm on a several control levels (i.e. stabilization, optimization). The paper focuses to the process of coal combustion and coal gasification. Primarily two processes are examined i.e. underground coal gasification (UCG) and coking. ...

Landslides are common and frequent geomorphic phenomena for the plateau regions in Romania having important consequences, especially economic ones, that needs designing scientific and technical plans for landslide risk mitigation. For this, an important preliminary step is assessing and mapping the landslide susceptibility. This paper examines a plateau zone in eastern Romania providing such a map, based on the landslides inventory, the digital elevation model (DEM) and the thematic layers of several factors thoug...

The increasing number of cars contributes to the degradation of human living space. This phenomenon affects both urban as well as residential areas. The communication system of housing estates made in the second half of the twentieth century in Poland was not designed for such a large number of cars that it has to handle today. Many factors influenced the present appearance of the prefabricated multi-family houses. First of all the obligatory standards, which assumed nearly ten times smaller parking rate than we a...

The paper deals with the removal of hydrocarbons C10-C40 from the river sediment using flotation and bacterial leaching. Flotation, as a purely mineral processing method, was used to remove a large percentage of organic pollutants. Flotation has not been applied in the cleaning of organically contaminated soils and sediments in the Czech Republic so far. The flotation collecting agent was Montanol 551. The flotation results show that the method appears as very effective as dominant proportions of the pollutants pa...

Using of HCAC as a clearing material of hydrometallurgical productionпїЅs effluent. Hydrocarbonoaluminate of calcium is synthesized in the system CaO-Al2O3-Na2O-CO2. Such system is characteristic for high silicon content aluminum raw on alumina processing plants by sintering method as desilication reagent. By this method aluminatesпїЅ solution decomposition conducts by carbonization receiving of aluminium hydrate and sodium liquor. HCAC has developed surface, neutral pH, which let us using it as clearing material ...

The article describes the chosen Japanese production and maintenance management philosophies, such as Lean Management, kazien and TPM. Japanese approaches to the process of work organizing and work planning, workplace preparing, tasks, duties and responsibilities turn out to be the most effective and the most efficient in the world. The practical application of these philosophies entails achieving the measurable benefits by the companies that use them. The basis of these philosophies is the elimination of all kind...

The possibility to use complexing reagents-collectors in floating different rare-earth and rare-metal ore has been studied. A prognostic assessment has been performed of efficiency of organic heteropolar compounds as flotation reagents-collectors on the basis of moleculeпїЅs energy parameters. The interaction has been considered of rare-earth and rare-metal minerals such as eudialite, zirconium, loparite and columbite with complexing reagents. Gain in energy (??) has been calculated by computer modeling at formati...

The article presents the possibility of application in civil engineering of highly ecological PET foam, manufactured from 100% recycled plastic packaging. It may find uses in construction of numerous engineering structures, such as pedestrian and cycle footbridges. Properly processed waste from post-consumer PET packaging may constitute a quality structural core for use in multilayered composite materials, commonly referred to as sandwiches. Their constructional function is to provide a distance between highly rig...

Underground mining operations are inextricably linked to negative impact on the environment. This impact, in particular, may result in the formation of mining damages (various types of terrain deformation) and pollution of the environment. It can also results in long-lasting changes in the landscape and environment. Sustainable management of areas degraded by mining exploitation requires an accurate stocktaking. Authors of this article presented the example of usage of GIS technology to develop a model of supporti...

This work is devoted to the synthesis and study of catalytic properties of mono- (Pd, Au) and bimetallic (Au-Pd) polymer-based catalysts of alkynol hydrogenation. Selective hydrogenation of alkynol C5 (2-methyl-3-butyn-2-ol) was studied over Pd, Au and Au-Pd catalysts supported on hypercrosslinked polystyrene of MN100 type bearing amino-groups. Synthesized Au/MN100 catalyst was shown to be promising for triple bond hydrogenation: more than 96% selectivity with respect to 2-methyl-3-buten-2-ol at 95% of the substra...

Energy efficiency and renewable energy are considered to be the twin pillars of sustainable energy policy and are high priorities in the sustainable energy hierarchy. In this context of continuous improve of energy efficiency in buildings; each state has developed different national politics on this direction. The obligation of the EU Member States to assimilate the strategy proposed by Energy Performance of Building Directive (Directive 2010/31/EU) determined the local communities to find financial resources and ...

This paper presents the possibility of using landscape metrics in the process of modeling vulnerability analysis of landscape qualities that should be protected when considering spatial decisions about its future land use. Modeling was carried out on the lower part of Krka River basin, in the Mediterranean part of Croatia. This area is under protection as a significant landscape according to the Croatian Nature Protection Act and it was chosen due to heavy developmental pressures that have resulted and still threa...

The flysch Carpathians presents geological medium that is especially difficult for deep recognizing with use of geophysical methods. Complex geological structure of folded orogeny and connected with it distribution of physical parameters generate ambiguous and frequently unreadable seismic image. In such circumstances looking for independent support for geological interpretation of seismic sections is purposeful, for example using magnetotelluric data. Magnetotelluric measurements were carried out along the select...

The article describes the results of the research project "Development of new technologies for surveying and cadastre", has been solved under the program to support applied research and experimental development "ALFA" and the provider of support Technology Agency of the Czech Republic. The aim of the project was to develop in the years 2012-2015, new technologies and software support for traditional surveying work such as documentation of detailed survey of changes, survey sketches, laying-out buildings, creation ...

The scope of this study is the application of a new approach for the estimation of potential soil erosion using a physically-based erosion model Erosion 3D for modelling potential erosion in the Myjava River basin, Slovakia. Erosion 3D is a physically-based model for predicting soil erosion by water on agricultural land. The model is predominantly based on physical principles and it simulates surface runoff, erosion, deposition and the detachment of soil particles for single events, and provides good tool to simul...

Well logging is usually used for monitoring the technical condition of the wells. This means whether there is degradation of the casing (potential subsurface damage of well) or not and uncontrolled overflow behind casingпїЅs strings. Measurement is able to cover both the static state of change saturation and the dynamic process of the ongoing spill in the relevant horizon. Furthermore, if there are monitored overlying horizons because of gradual overflow and saturation of the storage gas caused untightness of well...

The application of REACH and LCA systems to the coal waste was presented in this paper. Recent years has brought a growth interest in environmental management systems, which could minimize the negative environmental impact of chemical substances. As a result of that process standards such as REACH and LCA have been developed. Both of those systems are based on different assumptions. LCA refers to the whole life cycle of particular product and in consequence is considered as so-called пїЅfrom cradle to graveпїЅ stu...

Recycled Concrete Aggregate is a material resulting from the crushing of concrete elements. Currently, as a result of increased demand for natural aggregates, artificial aggregates are sought as an alternative materials in civil engineering activities. Recycled Concrete Aggregate characterizes high strength, but some properties, both mechanical and physical, remains unclear, which often discourages engineers to use this material. The paper presents the results of the California Bearing Ratio (CBR) and cyclic CBR (...

Currently, a great emphasis is put on the environment, energy intensity, and therefore on applications of the renewable energy sources (RES). Putting a large amount of RES into the modern distribution systems represents certain problems we can address, inter alia, the variable energy outputs of RES aggregated together, including their accumulation managed by respective energy management system (EMS). The result may be the optimization unit commitment of RES distributed in the micro-grids of a fictitious intelligen...

This paper presents a technique for the detection of elliptic objects connected with subsidence troughs in radar interferograms using the Hough transform. The generalized Hough transform to detect arbitrary shapes, including ellipses, requires a five-dimensional accumulator array, which occupies a very large part of the memory. For this reason, to overcome memory problems, a modified algorithm using a one-dimensional accumulator array was applied. This modification helped also to reduce the computation time. In th...

Intensive development of industry and urbanization have led to the increase of the waste water amount that pollute water flows. On the contrary, the need for water of satisfying quality continuously grows. The paper industry is one of those branches that are characterized by very high water demand and big amount of polluted waste water. In the meantime ensuring adequate quantity and quality of water is one of the most important goal of water resources management in paper industry. Water demand can be covered from ...

The chronometric geodesy is based on a relationship derived on the basis of the general theory of relativity, indicating a change of frequency and time at occurring change of potential. It is known that there is a possibility of using these relationships to determine geopotential changes, thus also height changes, by examining changes of clock rates in various places. From the formulas that describe this relationship, it can be estimated that at geopotential change by 1 m2/s2 (which corresponds to a height differe...

Calculation of the local scour behind the hydrosystem tailrace structures is associated with determination of hydraulic flow parameters, characterized by a sudden increase in the depth. The flow parameters are calculated on the basis of T. von Karman's integral momentum equation for a submerged turbulent jet. The flow in the hydrosystem tailrace, in accordance with the approach of G. N. Abramovich, is considered as a set of a submerged turbulent jet, a vortex area, and a main flow in the tailrace passage. It allow...

Mining is a complex and staged process that includes: prospecting, documenting, and mine planning, opening up and extraction of mineral (mining, transport, processing and deposition of waste), revitalisation and re-development of former mining area. Mining permit and decision on environmental impact of the enterprise are required prior to commencement of mining. During and after end of mining, impact of mineral extraction on surrounding environment, including surface deformation and the related mining damage, wate...

The commutation of inductive low voltage circuits of alternating current is accompanied by the occurrence of commutation over-voltages, often hazardous for the components of the electrical circuit. This paper describes a modern method for studying transitory regimes which occur at the disconnection of inductive circuits, based on the usage of a data acquisition system type NI-USB 6003 manufactured by National Instruments. The software used is Matlab, and the data acquisition method is based on Matlab programming. ...

The bioeconomy field covers the agricultural domain, all manufacturing sectors and associated services that involve any form of biological resources. Thereby, the research on bioeconomy is dependent on the data collection both about biological resources (such as plants, animals, and microorganisms) and about the connex phenomena. The remote sensing techniques provide an excellent way for the acquisition of information without making physical contact with these biological resources. So that, the remote sensing find...

In terms of development of agriculture, industry and tourism, in the spatial planning the level of exploration of mineral resources and environmental protection in rural areas is of great importance. The area of Vranje tertiary basin, located in the western part of the Serbian-Macedonian massif was selected. It spreads on both sides of the South Morava river, from Vladicin Han at the North, via Vranje and Ristovac to Bujanovac at the South. The total length of the basin is about 30 km and the width varies from 10 ...

The paper deals with applying of the biogeographic model of climatic conditions of forest vegetation zones in the Czech Republic to forest management strategy under predicted climate changes. The biogeographic model which was developed at Palacky University Olomouc is based on climatological prediction data for the time period 2010 - 2100 according to Representative Concentration Pathways regional scenarios and geobiocoenological data related to forest vegetation zonation. As results presented, climatic conditions...

The paper deals with applying of the GIS tool пїЅgap analyseпїЅ in order to assess the effectiveness of protected areas in floodplain forests conservation in the Czech Republic. European floodplains have been significantly influenced by human activities in the past. Despite of it floodplain forests are important biodiversity refugees and thus these forests habitats are in the focus of conservation efforts. Currently, the Natura 2000 network increasingly supports biodiversity conservation in Europe. Based on result...

For the analysis of various characteristics of natural objects distributions cluster analysis, principal component analysis and regression analysis are often used. There is a large number of distributions of the parameters of natural objects (e.g. spectral characteristics of soil), where the function is unknown, and discreteness is not visible, and contrary to the basic properties of described object. The soil cover is continuous in space and has no clear boundaries between spectral characteristics, such as soil l...

The management of solid waste is a challenge in municipalities of South Africa. The objectives of the study were to analyze the current status of recycling and challenges hindering efficient solid waste minimization mandate by municipalities in Limpopo province. The study employed both qualitative (through observation questionnaires interviews) and quantitative (fishers exact test) research methodology. The study was based on field surveys allowing for observation and measurement with respect to waste minimisation...

The technology of extending the service-oriented architecture of building configurable information systems is considered. The actual task is to increase the flexibility and efficiency of the newly created integrated information systems or services by providing the ability to configure the logic for the execution of functions that perform services in SOA. An additional task is to decrease the complexity of configuring the functionality of the service and to make it close to level of complexity of customization of b...

Machinery from all industries is subject to aging processes. For economic and time reasons, damage cannot be repaired by replacing worn or damaged parts, but the product must be reconditioned. One of the most used reconditioning technologies in the industry is welding. Reconditioning technologies are credible, when samples are tested standardized. In most cases, welded structures have undergone various types of destructive tests: tension, compression, torsion and fatigue.[1] Since fatigue tests cannot be made duri...

The depletion of light hydrocarbon resources and increasing the amount of heavy oil reservoirs drive petroleum companies to produce high viscous oil by unconventional methods, particularly thermal methods. Presently increasing the efficiency of thermal applications is a vital task. This paper discusses the influences of catalytic (introduction of catalytic precursors and H donor with amount of 1 wt% on oil) and non-catalytic aquathermolysis to the group composition and properties of extra-heavy oil from пїЅAshalch...