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The handling and disposal of voluminous sludge produced from water treatment plants poses difficulty to environmental scientist and engineers. In fact, its environmental friendly management and disposal is challenging task and requires careful consideration. In this study, sewage sludge ashes were examined as potentially supplementary cementitious materials. The raw sewage sludge was provided by two different municipal waste water treatment plants, coming from Poland and Greece respectively. The calcination of pre...

Maximum damage due to strong earthquakes occurs at the resonance between the natural periods of the structure and its site, given by the coincidence (or just close to) of the two periods, in which case the dynamic amplifications can damage, even destroy, the structure. From the recordings of (strong) Vrancea earthquakes one can see a dependence of the site natural periods and peak ground accelerations (PGA) on magnitude. For safe avoidance of the resonance it is necessary to define for each site a natural period v...

Brief Production of electrical power from renewable energy sources presents a chance to: satisfy the societyпїЅs power needs without encumbering the environment with combustion products of, among others, lignite and coal, energy security as well as become independent from traditional energy source suppliers. The aim of this article is to present the methodology used when designing wind farms utilising a group of wind turbines. The article presents the objectives of the European UnionпїЅs policy on renewable energy...

Paper describes the usage of fragmentation indexes in condition of Slovak Republic. The aim of this paper is to objectively evaluate the success of new territorial organization after land consolidation (LC) process. Four indexes of fragmentation are methodically evaluated (Shape - SI, Simmons - FI, Januszewski - K and Reduction index - RI) and endurance distance of one owner to its plots is determined in initial and new state. Thus established approaches are unique in Slovak conditions and mentioned parameters are...

Gemstones inspired people since the very beginnings of humankind due to their esthetic nature and as a symbol of lasting value and social superiority. Precious and decorative stones from the East Kazakhstan Region are known in this area of Central Asia since the early prehistory. The most precious among the Kazakhstan gemstones пїЅ emeralds пїЅ were processed by the factories in the Urals in the 16th-19th Centuries. Among other well-known non-metallic minerals there are sapphires, topazes and tourmalines, mostly o...

In our paper we deal with the evaluation and comparison of precipitation totals and interception in living and dead climax spruce stands at a research plot of ?ervenec during the non-vegetation periods (from approximately October to May) in the years 2012 - 2016. The difference in interception was analysed from October 2012 because during the summer 2012 the forests in the area died due to the infestation by the spruce bark beetle (Ips typographus). The research site is located in the Western Tatras (Slovakia) in ...

This paper is focused on the reuse of construction and demolition wastes in concrete production. From a large group of demolition wastes the concrete waste was selected. Tested concrete samples were prepared using coarse recycled concrete aggregate. In these specimens, fraction 4/8 mm were replaced by recycled concrete aggregate with a range of 100%. To reduce the absorption of the recycled concrete aggregate, the surface of aggregate was activated by a multi-stage mixing and using of geopolymer phases. To prepara...

Liquefied Natural Gas (LNG) is stored in cryogenic tanks at receiving terminals. During the LNG storage some part of LNG evaporates into gas phase. Evaporated LNG is called Boil off Gas (BOG). Heat flow has an influence on evaporation process. It indicates continuous boil-off of small fraction of LNG due to heat flow from the ambient air through tank insulation. Vaporization process causes changes in the composition of stored LNG. Increased vaporization process may negatively affect the stability and safety of the...

A learning algorithm was used as an artificial neural network (ANN) tool to predict the mechanical properties of some iron-based powder metallurgy (P/M) materials. Specimens prepared from atomized iron powder and from pre-alloyed iron base powders powders were analyzed in this paper. The specimens were fabricated by press and sintering of the mixed powders. The samples were compressed in a universal mechanical testing machine to a pressure of 400 and 600 MPa. The sintering temperature was approximately 1.150 пїЅC....

Information regarding activity on the market provides valuable source for the future managerial decisions of each company. They are very important for achieving company strategic goals which represent part of a long-term strategic management concept of the company. Highly-valued information concerns especially the sales and the expenses development. Development of set company's values can be predicted to a certain extent using mathematical methods. Company can adequately respond to its future predicted state of va...

The modern life and industrialization with their great impact and large scale of influence generates a colossal amount of waste products. Not only that they have huge physical volume but they also cause many short and long term effects on the nature, human way of life and all processes on the planet. The waste products' concentration in specific zones leads to conditions which makes them uninhabitable. The construction of landfills for industrial solid waste follows the modern requirements for disposing, encapsula...

The search for prospective sources of rare earth metals (REM) is one of the most important problems of the EU economy. Currently, it is believed that the source of REM may be deposits of coals or by-products of their combustion. A particularly promising appear to be fly ash from the combustion of coal because of much higher concentration of REM than in the coal beds. These facts and the dependency of domestic power energy on coal was an impulse to undertake work to determine the feasibility of obtaining the REM fr...

ZvolenskпїЅ teplпїЅrenskпїЅ Inc. is a company that has been providing heating for the town of Zvolen for decades. After the reconstruction in 2008, it is using low-sulphur lignite, wood chips and natural gas as a fuel, resulting in fine ash, that is collected nearby; however, it is spread by natural forces into surrounding gardens, forests, soil and water. To dispose of this ash ecologically, there is a possibility of using the Oyster mushroom Pleurotus ostreatus (Jacq.) P. Kumm, namely its ability of absorbing th...

Architectural restoration of historical buildings represents a very up-to-date topic of interest for the whole scientific community, architects, civil engineers and researchers. High performance and also aesthetical composite materials are continuously developed in order to fulfill the strict requirements of this sensitive area. Increased durability, superior mechanical characteristics, crack control for early cracking prevention and also smooth surface after removing of the mould / formwork represent a sum of pro...

Lake Suturuokha (69'06 "N, 145'23" E) is a unique lake within the Indigirka River basin, which is located on the border of the forest-tundra and taiga in the north of the Republic of Sakha (Yakutia). Formed due to the influence of glaciers of several glaciations in the late Pleistocene, the lake has a large area (69 km2) and comparatively shallow depths (2 - 2.5 m). Because of its unusual genesis and low study, the lake is of great interest to scientists. In August 2015, in the framework of the research expedition...

This paper reports the preparation of novel polymer membranes by phase inversion at room temperature (25 пїЅC), using acrylonitrile, acrylic acid, dimethyl sulfoxide and small amount of medicinal plant extract. We investigated the structure of the resulting membranes through Fourier Transform Infrared (FT-IR) spectroscopy and SEM microscopy. Also was determined the water content. FTIR-ATR spectra show that the peak at 1723 cm-1 shifted to lower wave number when medicinal plant extract (1715 cm-1) is added in the p...

In the present work, polymer-silica hybrid latexes based on methyl methacrylate (MMA), butyl acrylate (BuA), 2-hydroxyethyl methacrylate (HEMA), and different inorganic precursors (tetraethoxysilane (TEOS), isobutyltriethoxysilane (IBTES), diethoxydimethylsilane (DEDMS), vinyltriethoxysilane (VTES)) were synthesized by emulsion polymerization and sol-gel process. The resulting latexes were characterized both as materials placed into plastic vials and as films deposited onto clean glass slides by various techniques...

Synthetic polymers play an important role in the agricultural use as structural materials for creating a favorable environment for plant growth. Over the last few years the science of synthetic polymers has received great interest as one of the most exciting areas of polymer chemistry for the production of improved materials. The creation of multifunctional materials with prognosticates properties is important. The main objective of the research was to develop methods for the preparation of transparent hydrogels f...

Classic models of fault related folding frequently fails to describe complicated geological structures. The combination of tectonic modelling techniques can be used to reproduce observed geometry of folds. Indirect information contained in geophysical data can provide a good quality check for proposed tectonic models. The Draganowa Anticline is the westernmost part of the Draganowa-Iwonicz Fold. This structure is characterized by existence of very steeply dipping limbs in shallow zone which turns into gentle antic...

Our objectives were to investigate the bacteriological, biological and chemical status for sediment quality in a zone from Danube catchment according to Water Framework Directive. The area chosen for investigation is a large section of the Danube River on the section Bazias-Calarasi and its main tributaries located in the southern part of Romania (Jiu, Olt and Arges rivers) and the aquatic systems type пїЅdeltaпїЅ in the south-east of the Danube. All investigations performed where made in accordance with Directive...

The basic contractual instrument among all involved parties of construction projects in the Czech Republic is a contract for work according to the Civil Code of the Collection of Law of the Czech Republic. The contract is further supplemented by provisions based on long-term business experience and needs of contractual partners. An essential part is the type of price, its amount and the method of determining or adjusting the price. For green constructions in general and green buildings in particular it is customar...

The priorities of the state policy of the Russian Federation in the Arctic is determined primarily by the Strategy of development of the Arctic zone of the Russian Federation and national security for the period up to 2020, approved by the President of the Russian Federation. In the framework of the activities of the Russian State Commission on Arctic development a working group "Education and Science" under the leadership of the Ministry of Education and Science of the Russian Federation. This group had analyzed ...

When aiming to study pro-environmental behavior (PEB) developments at the local municipal level in Latvia, there were two complementary studies employed: 1- main local stakeholder groups interviewing in two town municipalities to study their existing PEB practice, especially obstacles and related municipal governance instruments; 2- questionnaire for about 100 Eco-schools (EcoS) coordinators in Latvia to study schools existing PEB practice within school grounds, but especially their orientation towards and collabo...

In connection with the significant destruction capability of tornado, the possibility of tornado passing through the areas comprising higher criticality rating facilities, such as nuclear power plants (NPP), is considered during the design and engineering (D&E) phase for such facilities. Corresponding probabilistic safety criterion in introduced into the decision-making basis concerning the consideration of tornado's impact onto the hazardous production facilities and destruction loads computation during the D&E p...

This contribution deals with the verification of airflow in the real air gap of an insulated roof deck with a pitched roof. The designed construction of the roof meets the thermal technical requirements for an energy passive house. The aim of this contribution is a comparison of experimentally measured values with values obtained through a computer simulation. Double skin ventilated roof structures operate on the principle of the removal of moisture vapour by the flow of air. The flow of air is generated by the di...

Mathematical models of the dynamics of spacecraft with a solar sail to control translational orbital motion and rotation of the whole structure are provided the stability of the sail orientation relative to the flow of sunlight. The behavior of solutions in a neighborhood of the possible equilibrium or stationary state of motion is taken into account. Change in the stability depending on the tasks and the transformation of equations that describe the perturbed processes is taken into account. It is possible to var...

During mining activities the constructions on the surface are usually influenced. Extent and time course of negative influences is dependent on array of geological, hydro geological and mining conditions and last not least also on the way of implementation of line construction (i.e. how it is ready to react to these awaited influences). In the past for that reason the array of calculation methods working with more or less precision with using for prognosis of influence of mining activities (i.e. influence of minin...

The article analyzes the necessity of forming a model of environmentally sustainable development. It is determined that the solution of this problem is extremely necessary for Russia. The characteristic of the basic concepts of solving global environmental problems is given. It is determined that the solution of this problem is extremely necessary for Russia. The characteristic of the basic concepts of solving global environmental problems is given. The need is formulated to consider nature as an economic category...

At the moment in Romania there are a total of more than 7000 individuals and legal entities authorized by ANCPI (National Agency for Cadastre and Land Registration) for geodetic, photogrammetric, cartographic, cadastre and land registration works [4]. According to ANCPI standards there are regulated minimum technical conditions necessary for authorization including types and performances for geodetic and topographic equipments. At the national level the State Legal Office of Legal Metrology (BRML), which is in cha...

The competitive markets complemented by the concern for resources and environmental protection represent real and actual challenges factors for any organization. The customers call for special attention and organizations integrate the customer-centred approach in their strategies as main vehicle for achieving performance objectives. One of the well-known methods in this matter is referring to the Total Quality concept which supports checking and implementing different quality models needed to improve the competiti...

Finite Element Method is one most popular contemporary method of strength analysis. The method is an advanced method for solving differential equations, based on discretization, which means that area is divided into finite elements. Each finite element has a solution of the equation approximated by specific functions and performing the actual calculations only for nodes of this division. Finite Element Method is widely used in structural strength simulations, in which features such as deformations, displacements, ...

Mining activity represents an important source of harmful emissions into the environment and general impact on the environment. In the Ostrava industrial region this activity represents one of the most serious sources of potential risk for the environment and public health. The article deals with the problem of emissions of a mining enterprise from the point of view of air pollution and potential influence of air pollution on public health for the population. In particular it deals with air pollution impacts from ...

The main purpose of any socio-economic system is the quality of life of the population. Factor of production is dominant in the regional economy to achieve those goals. Creating conditions for the development of industrial production, is subject to state regulation, including all levels of government. However, responsible for the achievement of the final goal are also enterprises, organizations and citizens themselves. Production potential and quality of life of the population-are directly linked to the level of e...

The intensity of scientific and technical progress is the most important factor in the sustainable development of the economy, its economic and environmental security. In order to increase the intensity of scientific and technological progress in Russia was developed a state program "Development of Science and Technology" for 2013-2020. One of the main tasks of this program is "the formation of a modern material and technical base of the research and development sector." Measurement of the supply of material and t...

The research aim is to estimate the profit a forest owner can earn per full forest rotation cycle from forest stands of dominant coniferous species in Latvia, selling both the assortment of logs and biomass (BM) from final felling. The research analysed the situation in privately managed forests, composed of the coniferous species пїЅ Norway spruce (Picea abies L.) and Scots pine (Pinus syllvestris L.) пїЅ in different forest types in Latvia. The calculation of revenue from forest product sales took into account b...

The research aim is to identify a financial gain a forest owner can make from the management of a deciduous forest stand in Latvia provided that the stand is logged at the final (clear) felling age and the revenue is earned selling the wood as roundwood assortments and residue biomass or only as biomass (BM). The present research analysed the situation with forests owned by natural persons of the Republic of Latvia and identified the amounts of revenue a forest owner can earn growing deciduous пїЅ birch, black ald...

The Ukok plateau is located in the southern part of the Altai Mountains on the altitude of 2200 пїЅ 2500 meters above sea level, at the junction of state borders of Mongolia, China, Kazakhstan and Russia. Despite the severe climatic conditions, the territory was populated and developed by representatives of numerous cultures, who had left their traces up to the present day in the form of numerous archaeological sites. The archaeologists investigated the location of the majority of archaeological sites. However, wi...

The article describes program and algorithmic complex for synthesis of computer vision. This method operates as part of an automated control system for climate testing and it designs to analyze the aging of rubber products according to their visual indices. In this article the structural scheme of the system has been given. In addition, modified methods have been described. They compare the coordinates of a series of photographs, eliminate noise in the image being processed, and convert the output data of the comp...

The progressing depletion of fossil fuels necessitates the search for renewable sources of energy around the world. The reconstruction of small hydroelectric power stations is an alternative solution for the sustainable generation of energy. The objective of this study was to reconstruct a small hydropower plant in its former location. The average water flow and annual water flow were calculated, and the results were used to design a water turbine with a gear unit and a generator. An Archimedean screw hydroturbine...

The purpose of this research was to study, analyze and evaluate strategies and concepts for recycling of waste related to the rests of burning processes form fossil fuels in the energy sector in transition countries. Accordingly to the European Opinion approach the objectives in future are to reduce the fossil energy resource utilization in order to minimize the negative impacts on the environment and human health. Meanwhile in countries that largely depend in energy production based on thermo power plants the mai...

Research Objective: To develop the rationale behind the implementation of low-waste technology in the light of development goals of mining company. The goals are determining the anticipated project results that are usually divided into economic, social and environmental results. Project methodology is different under the context of low-waste technology projects. Methodological Framework is based on the interdisciplinary methods, modern concepts of waste management and recycling under the context of mining operatio...

Cereal farming is an important sector of agriculture in Latvia, which determines the development of crop farming. In 2015, 22.5 thousand farms were engaged in cereal production in Latvia. Of the total output of cereals, 64% were produced by intensive farms with an area of more than 200 ha, which accounted for a few percent of the total cereal farms. The cereal sector has developed in Latvia after joining the European Union (EU) owing to direct support payments and export opportunities. It is important to project t...

Today, sustainable development is related not only to sustainable production issues but also to a sustainable consumption. In the planning document пїЅSustainable Development Strategy of Latvia until 2030пїЅ, special attention is focused on enhancement of ecologically certified and healthy products, thus shaping the image of Latvia as a пїЅgreenпїЅ country by promotion of sustainable eating habits and cultural heritage. To position Latvia as one of the пїЅgreenestпїЅ countries of the EU, the consumers, food produc...

Fused Deposition Modeling (FDM) is one of the most used technology in the 3D printing field. There is many kind of 3D printers with different design and parameters, such work temperature, deposition speed and others. All of these parameters affect the final parts. Produced parts are made from different materials and therefore there are also different mechanical properties. So it depend what for the produced parts are designed, if there are just for design introducing or even for real use as conventional produced p...

The paper describes the possible applications of expanded polystyrene (EPS) granulate derived from recycling for the production of prefabricated building units. Test results of a new material called Polytech and its application in the construction industry are presented. Polytech construction system is based on prefabricated large-panel units. An important advantage of the new material is the volume representation of EPS granulate, which reaches up to 60%. So far пїЅ in order to keep the proper strength of the man...

The use of weak local soil as well as the recycling of existing worn-out structures such as old road pavements using micro particle road binders are a beneficial ecological solutions. Parameters of the soil stabilized with binders significantly affect the load bearing capacity and durability of the built structures. Mechanical parameters of the soil are therefore needed in the analysis and design of soil structures. Determination of the exact value of these parameters in indirect tensile test is related to the nee...

The forest is generally recognized as a major environmental and stabilizing factor in the country. Its stability is currently significantly influenced by changing climatic conditions. They are an important factor in a determining species composition of forest ecosystems, as well as ecophysiological and production processes directly linked to the overall performance and stability of forest stands. Dry summer months and warmer winters with negative anthropogenic activities actually create more favorable conditions f...

In my paper, I analyse the existing curriculum on the subject of ecological education in Romanian schools, in order to offer some practical solutions that can be implemented in kindergarten, schools, universities and also during cultural events and fairs (that I also consider an important educating factor). The abstract information taught at the higher levels of education dominate the curricula of our schools and universities, where pupils and students get very little practical knowledge пїЅ either concerning a pa...

Roundabouts are generally perceived as safe solution of dangerous intersections. If they are built correctly, number of traffic accidents is lower than in case of common intersection types пїЅ it relates also to severity of results (i.e. fewer deaths and serious injuries, and lower property damages). In comparison with uncontrolled intersections the roundabouts have higher capacity available. Czech standards and technical conditions assess roundabout capacity on the basis of calculation of capacity for approaches ...

The goal of the contribution is to elaborate the analysis and prognosis of groundwater level regime using numerical modelling to show the possibility of introducing technical measures which have to mitigate the unfavourable groundwater level regime in the vicinity of the hydraulic structure. For numerical simulation purposes a mathematical model by means of finite element method has been provided in right-side alluvium of the VпїЅh River with detailed concentration on endangered village in the vicinity of the hydr...