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In the current context, characterized by the alarming increase in pollution caused by energy production from fossil fuels it is becoming increasingly important to reduce this dependence. Wind energy can be a very good solution to global energy problems. Romania's wind potential is considered one of the largest in Europe, the Dobrogea region having the largest wind potential in Romania. The objective of this paper is to draw an image of the near future projection of the wind potential in this region. The problem of...

Geotechnical soil model is a result of extensive investigation techniques and represents the base for quality landslide characterization. Paper presents a geotechnical investigation process in a six distinctive phase workflow on the case study landslide Orehovcak in northern Croatia. The process starts at the office by collecting available information relating to the site topography, as well as all available geology maps and data. The second phase incorporates detailed field mapping and survey of structural damage...

One of the complicating factors in oil production is the deposition paraffin, as a result of which the production well rate is decreasing and the Electric submersible pump failure occurs. The main factors influencing the intensity of paraffin formation are: downhole temperature, gas evolution, hydrocarbon composition in each phase of the mixture, high viscosity of oil, change in the velocity of the gas-liquid mixture. To solve problems, the thermal method is used, which consists in artificial increase of the well ...

The objective studied is a collective dwelling with the height regime of S + P + 3E and offices located on Str. Borhanci, Cluj County. From a geometric point of view, topographic surveying works ensure the application of various types of constructions, ways of communication, art works, hydrotechnical works on the ground. In our case, the execution of the tracing works was accomplished by moving from the upper to the lower order, from the geodetic state to the tracing base. An essential factor was the choice of the...

The global economy needs significant changes that will reduce the high consumption of natural resources and the amount of waste generated. The idea of solving the circular economy proposes a path to solve such problems. Thematically, it covers social, political, economic and production issues. However, it should be noted that Circular Economy is not a ready recipe for solving the problems of depleting raw materials and the deteriorating condition of the environment. The basic premise of Circular Economy is a simpl...

The article analyzes the prospects of transition of the Russian fuel and energy complex to the new development paradigm which consists in implementing some Industry 4.0 Project elements. The article attempts to identify the profound changes taking place in the global and Russian energy sectors. One of the key drivers of the new development paradigm is the active implementation of the Industry 4.0 project elements in the fuel and energy complex, which is comprehensive and relies on digital technologies. The feature...

Currently, the population of the Earth, reaching a value of 7.2 billion people (2014), continues to grow rapidly. This leads to an increase in the demand for food, energy, minerals, which in turn enhances the anthropogenic impact on the biosphere, at the same time increases production and consumption waste and worsens the ecological situation. The problems of urbanization should be attributed to the most acute technospheric problems - increasing the role of cities in the development of society, as well as the grow...

Natural hydraulic lime (NHL) belongs to traditional binders used in civil engineering for centuries. Hydraulic lime (both natural or artificial) may be considered as binder which properties represents a transition between air lime (pure CaO or Ca(OH)2) and Portland cement (PC). It means that NHL contains hydraulic compounds (as PC) and CaO/Ca(OH)2. The significant difference is in calcination temperature ? NHL is calcined at lower temperature than Portland clinker i.e. there is lower energy consumption (and carbon...

Levulinic acid (LA) is a substance, which can be obtained from cellulosic biomass via acid hydrolysis. Hydrogenation of LA to gamma-valerolactone (GVL) is one of the most promising reactions in the field of biomass valorization to fine chemicals and liquid transportation fuels. Potentially, GVL obtained from lignocellulosic biomass is a versatile intermediate for the production of fuel additives and chemicals. Due to the high demand for GVL, its efficient production is currently a topic of intensive research. This...

The high number of freshwaters and wetlands is a characteristic feature of arctic and subarctic landscapes in the northern Russia. Arctic freshwater ecosystems are especially susceptible to the negative consequences of global environmental change drivers. We studied zooplankton communities of 14 small tundra lakes in the Pechora River delta (in the northeast of European Russia). The composition, structure of zooplankton, and ecological stage of lakes were analyzed. A total of 107 zooplankton taxa were identified. ...

Zooplankton plays a significant role within the Black Sea ecosystem, contributing to the top ? down regulation of trophic web, by intermediating vital ecological processes such as the nutrients recycling (e.g., by controlling phytoplankton and bacterial aggregates development) within the pelagic and benthic habitats. It is considered an important indicator of ecosystem health, being a quality assessment element within the Water Framework Directive (2000/60/EC). Based on the 55 samples collected in the Romanian wat...

Mining, due to its intensive economic operation, is primarily associated with negative impact on natural environment and destruction of natural assets, and that regardless of the method of raw materials extraction. So, the great challenge now is to restore natural balance to areas affected by the consequences of this operation. Literature on the subject features a lot of publications on recultivation, understood as reintroduction of forests, meadows, arable land and water courses into degraded former mining areas ...

Heavy crude oils are extracted mostly by thermal recovery methods which reduce viscosity of heavy oil due to destruction of associative bonds in a complex oil fluid. In a number of articles, it is proved that at a temperature of more than 200-250В° C there is also a certain chemical transformation of hydrocarbons, primarily containing hetero-elements. The use of finely-dispersed catalysts, injected directly into the oil-bearing formation, allows to intensify the processes of destructive hydrogenation of asphaltene...

The company "Skripinsky Quarry", LLC is mining the carbonate rock deposit. Planning the advanced processing of raw materials, the company is doing a lot of work to develop new types of products. The integrated approach to the territory development became the key for the enterprise developing the promising industrial projects. The competition of project proposals for the best use of Skripinsky quarry crushed stone screenings was organized together with D. Mendeleev University of Chemical Technology of Russia. The w...

The underground mining of a deposit leads inevitably to the deformation of the surface as well as to the destruction of the buildings located in the area of influence of the extraction. Therefore, the rocks surrounding the excavation, created by the extraction process, go from the initial equilibrium state of tensions (triaxial) to a biaxial or even uniaxial stress state. This secondary state of tension leads to the occurrence of rock breaking phenomena in the areas where their resistance are exceeded, respectivel...

In 2017 for the first time in Kazakhstan we gave several lessons at the Abai Kazakh National Pedagogical University (KazNPU) in Almaty, through the instrumentality of the ?flipped classroom? method within the frame of the following disciplines: ?The theory of evolution? for undergraduate students and ?A modern human physiology? for graduate students. In accordance with the requirements of employed method, teaching and learning process was built in such a manner. Teachers provided to the students educational materi...

The aim of this study is to validate the possibility of using the 100 Megapixels Hasselblad Hd-6 middle format camera and Agisoft PhotoScan in the Cultural Heritage documentation. The subject of this investigations is the fresco decoration in one of the rooms in the Bieli?ski Palace in Otwock Wielki, near Warsaw (Poland). The frescos cover the walls of a room of 11,5 ? 5,5 m in one of the wings of the palace. The results of the data analysis convincingly show that a higher resolution can be obtained using a Hassel...

Accessibility to urban facilities and public services is nowadays one of the key factors that impacts the quality of urban live. That being said, accessibility is a complex concept, which although in common use, has a range of meanings, and measuring it raises numerous methodological problems. For instance, accessibility is closely related to the concept of distance, but as a society evolves, other factors such as travel time, economic cost, different transport options, interest or attraction of the destination co...

In this study, we collected data from nine domestic Irish bank web sites and nine domestic Finnish bank web sites. Both countries have many similarities in political, demographical, financial and economical areas. Each of the selected banks represent a typical domestic bank, which is under the control of the respective national central bank. The results of the study could be used as a guide for good and bad practices because of highly qualified personnel employment in the credit institutions, decisions are based u...

The implementation of underground coal gasification (UCG) on an industrial scale requires solving many problems. One of them is the optimization of chemical processes during gasification, such as pyrolysis, in order to obtain a syngas with the desired parameters. The process of devolatilization a coal seam in underground conditions is complex, moreover, many issues are not fully understood. Due to the limited possibilities of experimental research, simulation research is extremely helpful in understanding the deta...

In this paper, a computational method to predict the corrosion resistance of some ironbased powder metallurgy (P/M) materials is proposed. The samples prepared from atomized iron powder and pre-alloyed iron base powders powders were the materials analyzed in this paper. The compacted samples were obtained by powder metallurgy process, respectively pressing and sintering of the mixed powders. The samples were compacted at a pressures of 400 and 600 MPa. The sintering temperature was approximately 1.150 В°C. The inf...

This paper presents the problems of ship-generated waste management in port areas. The first part contains a classification and characterisation of ship-generated pollution, with a particular focus on waste and cargo residues. Further to that, the legal and documentation aspects of waste management in seaports are discussed, along with the basic principles of rational waste management. The second part of the paper presents a diagram of the waste management model within a port area and analyses each individual stag...

Digital ecosystems represent a new technology capable of interconnecting heterogeneous, cross-domain platforms, able to drive innovation in different industries, enabling us to connect and operate with a wide range of actors, customers, partners, companies. Digital ecosystems can be considered as socio-technical clusters of adaptive applications with different levels of context awareness, adaptability and autonomicity. The adaptive properties of an organism are closely related to the self-organizing property and t...

The proposed paper presents the situation of the Aranca hydroameliorative arrangement located in the western part of Romania. The Aranca hydroameliorative arrangement was realized in 1965 and the completion of the land improvement works in this arrangement were realized between the years 1974-1977. Since the execution, a series of rehabilitation works have been carried out due to changes in agricultural practices in the area affected by climate change. This research assesses the state of the art as well as its fun...

The proposed paper presents the situation of the Teba-Timisat hydroameliorative arrangement located in the western part of Romania. Teba-Timisat hydroameliorative arrangement was realized in 1962 and the completion of the land improvement works in this arrangement was executed between 1985 and 1987. Since the execution, a series of rehabilitation works have been carried out, due to changes in agricultural practices in the area affected by climate change. This research assesses the state of the art as well as its f...

The article analyzes how the main factors influence the competitiveness of the economy. In constructing the model, three assumptions are introduced: a) there is a prehistory of the process, i.e. the variables that evaluate the competitiveness of the economy at the time t, also affect the values of previous periods; b) there is a mutual influence (interdependence) between the variables that evaluate the competitiveness of the economy; c) the variables that evaluate the competitiveness of the economy are influenced ...

SF6 insulating installations are today the most performing technical solution applied to high voltage devices such as circuit-breakers and surge arresters. This gas is used due to a lot of excellent insulating properties. These properties are depending on many variables, one of them is electrodes? geometry and material. Generally, when studding the dielectric breakthrough process, ideal electrode surfaces are taken in consideration. But many experimental results, different than theoretical ones, could be a consequ...

The visual alteration generated by quarrying sites on the surrounding areas constitutes a crucial step in the assessment of environmental impact such activities determine on the landscape. The case study presented in this paper refers on the application of an improved method to assess such alteration taking into account those parameters affecting the visual intrusion by means of a quantitative approach. In particular the assessment is firstly carried out using the visual impact indicator introduced by the EC decis...

Study of wave motions fluid is one of the most important and complex problems of modern hydrodynamics. This issue is receiving significant attention in fluid mechanics, hydraulics, acoustics, oceanography and physiology of circulation. Special mention should be made of the relevance of the objectives of the movement body of finite size in fluid, ship hydrodynamics tasks, tasks construction of coastal protection, as well as the increasing interest in modeling the planet's climate. The fluid flows in the presence of...

Acid Orange 7 was heterophotolyzed using titanium dioxide, oxygen bubbling, back-flow tubular reactor, polychromatic radiation of high pressure Hg lamp and aqueous sodium bicarbonate, sodium hydroxide or sulfuric acid as solvents. Dependences of reaction rates on Acid Orange 7 concentrations have exhibited either straight-line (for lower initial concentrations) or a convex shape (for higher initial concentrations). Variations in shapes of kinetic curves observed were explained by the effect of decrease in both (i)...

In the paper the problem of coal permeability enhancement by hydraulic fracturing with the lightweight proppant is considered. The used proppant consists of hollow aluminosilicate microspheres ASPM-500. The experimental results of the lightweight proppant influence on the long-flame coal permeability are presented. The permeability of coal with a propped crack is reduced by 4-9 times as the confining pressure is increased by 5 times from 1 to 5 MPa. The permeability decrease may be caused by the proppant pack comp...

Many automated processes in the forestry sector require a tree species classification to locate individual trees or to distribute data to several species. There is already a huge number of classification approaches, which can be found in the literature. But still there is no global tree species classification available. The difficulty of a global classification is based on the variance in the appearance of the same species in several locations. This is mainly due to two problems: First internal disturbance - trees...

The article shows the new methodical approaches to evaluation of planning quality and realization of technological water use process as for irrigation systems as a whole, as for separate irrigated plots on agricultural premises and on farms. There were based and developed: a new classification of irrigation systems, a new method of standard calcu-lation and possible limits of change in technical, ecological and economic values at wa-ter use on irrigation systems. There was proposed a system of technical and econom...

The article introduces systems theory in evaluating and forecasting environ-geotechnical hazards in the central area of Hanoi city. The advantage of the theory is that it includes all the conditional factors and causes of the hazards, as well as the relationship between the factors. The role of each factor is quantified and summarized by mathematical formulas, which can produce an accurate evaluation of hazards status and reliable forecast. The systems theory applied in evaluating and forecasting environ-geotechni...

Due to economic and social benefits it provides, transport is a key sector on which development is based. However, adverse effects of transport in terms of the environment, economy, and society ought to be minimised. The European Commission has developed standard indicators to evaluate negative effects of transport and its sustainable development in Union countries. This paper presents these indicators and provides their synthetic analysis. The indicators reveal that several countries (e.g. the Netherlands) develo...

The main idea of this paper is to develop a multi-agent system, integrating advanced control algorithms and acting scenarios, for optimizing energy management in an intelligent microgrid. In order to achieve this objective, it is proposed a flexible intelligent tool based on multi-agents, able to give alternatives for action to prosumers, through a specialized interface. In this respect, firstly are presented aspects related to the multi- agents (MAS) integration in smart grids? control. In the second part the wor...

One tenth of the European population lives in distressed areas where physical and economic plight is aggravated by social problems. In urban renewal, two emerging problems require attention: a) the inclusion of the local communities in making choices for land administration; b) the complex nature of the interventions due to the multiplicity, diversity and conflict of the elements involved. With the aim of providing an evaluation procedure able to aid public choice, to involve the community and to reach a shared ch...

Numerical modeling of vortex induced motions appears to be one of primary objectives of offshore constructions design. The flow around structure elements with certain elongated geometry shape as pipes, risers, mooring lines, oil rig legs etc., causes vortex induction, which in turn could lead to negative side effects such as cross motion or even to structural damage. The vibration process modeling in advance could allow the structures design and production without extra margins of safety and therefore the final pr...

The imitator of self-contained self-rescuer is a component of training complex for personnel of coal mines and represents an effective application for development of skills of work with self-rescuers in regular and emergency situations. The task of design of mobile multi-usable self-rescuer imitator with chemically bound oxygen supply in the absence of regenerative chemical agent was formulated. The features of imitator are its mobility (wireless design) and the ability to create and transmit in real time via Wi-F...

Unglazed transpired solar collectors (UTC) are simple and effective devices for applications such air heating, induced ventilation, crop drying etc. A numerical model for typical unglazed transpired collector is proposed with blackened plate exposed to the sun and circular holes on square pitch arrangement in no wind working conditions. The steady-state conservation of mass equation, momentum and energy equations were considered in order compute the air pressure and velocities, flow pattern and the total air heati...

Buldan region is almost 45 km from Denizli (Western Turkey) province. Terrestrial sedimentary units are deposited throughout the Denizli Basin in age from the Early Miocene to Present. The coals are located in Middle Miocene K?z?lburun Formation consisting of conglomerate, sandstone and mudstone lithologies. Coal samples were studied using standard total organic carbon (TOC) and kerogen pyrolysis analysis of the whole rock samples and organic petrographic methods. Average TOC content, S1 and S2 values of investiga...

The article presents the importance of abandoned quarries for the mosaic landscape structure. Five objects {and} their surroundings in a 100-m zone located in the Polish Western Carpathians were analysed in terms of plant communities, flora, physical and chemical parameters of soils, and diversity of relief. The objects, which were originally used for excavation of marls, were characterised by the largest differences in soil parameters between the quarry and the surroundings. Xerothermic vegetation was noted to ha...

Humus comprises one of the largest reservoirs of carbon on the Earth. Nevertheless, humus and humus-derived products have been utilized to a relatively small extent in industrial applications. This is in contrast to coal, which was the basis of much of the chemical industry in the latter part of the nineteenth and the early part of the twentieth century, and petroleum which is the major raw material for much of the present day chemical industry. The purpose of this paper is to document an ability of a humus-like m...

The field of construction is considered as a priority in terms of influence on the environment. Attention of researchers is now focused on composite materials made from natural or recycled fillers with clay, cementious or polymerics matrices, among which the non-toxic and biodegradable - Eco-composites, are highlighted. These are attractive because they are safer and more environmentally friendly. Eco-composites are a special category of composite materials, using materials that have the least impact on the enviro...

Energy efficiency is a key factor of today?s engineering practice. Water and wastewater systems (made up of supply and disposal networks, treatment plants etc.) often contain under pressure sections. Their energy efficiency strongly depends on the accuracy of the head loss evaluation including local head loss. In these systems a great amount of local head loss is given by different valves. Gate valves and check valves are being widely used in water and wastewater systems, therefore this article focuses especially ...

Unconventional energy sources have gained and will continue to gain a growing share of energy systems around the world, both because of the research effort and the political will involved in their development, and because of the price increase of energy obtained through traditional methods. In order to take advantage of the opportunities offered by the international energy transition process, Romania must undertake new directions for development in the energy sector. Conventional energy sources based on oil, coal ...

The paper emphasizes the ecological restoration (renaturation) of the natural conditions of a saline soil, which was previously under long term melioration. The soil is a Salinic Pelic Alluvic Sodosol with relict gleization, covering an Alkali soil (according to SRTS-2012). The site is located in Moldova Tableland, where Tma is 584.6?C and Pma is 9.5 mm. The depth of the groundwater table is about 1.80 m, with frequent seasonal fluctuations and weak-moderate mineralization. The soil had a polyphasic evolution, bot...

In this paper, a pipeline implementing a multi-scale approach that can be used for modelling different steps of aerogel production is presented. Closely integrated modules for aerogel structures generation, properties prediction and adsorption, diffusion and chromatography processes modelling provide various options for systematic and comprehensive study of aerogels by performing computational experiments, which allows to reduce number of laboratory experiments. The results of pipeline validation are presented for...

The demand for an indoor navigation service is increasing as indoor positioning technology is developed, therefore it is necessary to construct indoor network data that can be directly used for navigation. In this study, indoor network data were constructed using indoor evacuation map images, which can be easily obtained. The evacuation route in the map can be used as network information because it represents the connection between each room as well as the connection between room entrances and the main entrance of...

The stone dust coming from stone processing plant located in Ostrom??, Czech Republic, was examined in the presented paper as an alternative recyclable environment-friendly material which can be effectively being used in construction as partial replacement of natural sand. The tested dust is grey-brown colored and is a byproduct of sandstone processing from quarry Podhorn? ?jezd. Before the characterization tests, the delivered stone dust was sieved on a certificate test sieve with a 0.25 mm mesh size. First, basi...