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Jiu Valley mining area is one of Romania where currently exploiting a coal deposit, which has important reserves of balance that can ensure beneficiaries' needs (CET Paroseni and CET Mintia) over a period of several decades. Structural changes that have occurred in the Romanian economy since 1989 have generated, but layoffs / redundancies collective personnel reorganization / activity restrictions in the mining units and the closure of some mines with no prospects of viability. All this led to a sharp economic dec...

The atmospheric sound waves with frequencies lower than 20Hz are named infrasound waves. Among the multitude of infrasonic signals that have been recorded and detected during time, some of them have been associated with different natural or anthropogenic sources and the source of many other remaining hidden and unknown. At the beginning of year 2013, a permanent infrasound monitoring system composed by a MB AZEL2007 microbarometer, the digitizer and the transmitting equipment, was installed by NIEP, at Mangalia, R...

This paper describes an experimental analysis of damaged concrete corbel strengthened by gluing carbon fibre composite fabrics. The purpose of the investigation is to study all changes in behaviour and then their contribution to a better understanding of reinforced concrete corbel. Five reinforced concrete corbels are tested under tree-points bending to failure. Four of them are damaged at different load level up to 80% before strengthening. Test results show that strengthened corbel specimens using glue given an ...

The study of the structure and formation of shores is now modern issue, both in the assessment of their morphology and the ecological conditions of the steppe zone of Kazakhstan. The article reflects a structure of abrupt bank of Northern Kazakhstan rivers in conjunction with the soil adjacent to it. The authors believe that the intrasoil runoff has not been taken into account so far due to the presence of both soil genetic cracks and high permeability of humidified moisture to "puffy" fouling. Therefore, there sh...

With a cultivated area of over 2x108ha, wheat is the largest crop worldwide by cultivated surface. For wheat crops, the production suffers loss caused by weeds, and depending on the weeding level, the fertilization level can surpass 50% (1). Weed management is just one of the technological components present in any crop technology. Given the biological particularities, wheat crop is mainly weeded with dicotyledonous species. The objective of this paper is the comparative evaluation of the classic method for determ...

Hydrochemical studies of mine water on abandoned Nagornaya mine showed that they are weakly alkaline with high color, permanganate demand (PD) and content of iron cations compared to Russian state legislation standards for natural water of a different type. Mine water are polluted with Na, Li, Cu, Ni and Sr cations, while gas chromatography identified some saturated hydrocarbons, mainly from ?22?46 to ?32?66. The study demonstrates a developed technology of local mine water treatment with a high color, PD and iron...

The paper analyses the waste management practice for the Arad County located in the western part of Romania. Together with Timis County it forms a prosperous region in Romania, attracting numerous foreign investors, especially because its proximity to the border. The transformations that led to the modernization of land in this county were radical and occurred unevenly. The main driving forces of resource consumption are economic growth, technological developments and changing consumption and production patterns. ...

Eco-grammar systems represent grammar systems which were motivated by the behaviour of ecosystems. They were introduced in 1994 in order to describe evolving environment and community of agents together with the interplay among them. Positioned eco-grammar systems (PEG systems, for short) were introduced in our previous paper as a variant of the eco-grammar systems. Motivation for introducing the PEG systems and its main difference from the original eco-grammar systems is that we focus on the embodiment of the age...

The aim of this study is to explore the possibility of recycling waste materials of brick aggregates (BA) and demolition concrete aggregates (DCA) in the self-compacting concrete (SCC), by studying these fresh and hardened properties. A reference mixture based on natural aggregates (NASCC) and six mixtures incorporating recycled brick aggregates (BASCC), recycled demolition concrete aggregate (DCASCC) and combination of recycled brick and demolition concrete aggregates (BDASCC), as replacement of natural aggregate...

With the current situation in world economy, rare earth elements are a valuable resource for many innovative technologies. Low supply of these elements and sparse mining sources concentrated in just a few countries caused REE to become a resource critical to the development of many high-tech branches of the industry. Although rare earth elements are widespread in the nature, due to their low concentration in most minerals, their processing based on flotation, gravity or magnetic separation of a concentrate is ofte...

Degraded post-mining areas have considerable potential for redevelopment. They are usually located in attractive urban areas and have convenient road and rail links to the rest of the city and other places in the region or country. These areas are often equipped with power, water and sewage systems. The redevelopment of these sites could take place in many different directions. They can be used to carry out production, service, commercial, residential and leisure activities. However, the unstabilized legal situati...

The research goal was to make a dimensional comparison of an average droplet of a fuel spray for two fuel supply methods to a standard fuel injector in diesel engines. The Sauter mean diameter (SMD) and other derived parameters were determined in a selected spray cross-section using Spraytec STP5000 instrument. Apart from determining a mean droplet diameter, the software allows for computing numerous derived parameters. In the first case, W1F-01 fuel injector (opening pressure - 23 MPa) was supplied by a fuel pump...

Ecosystems are open adaptive systems with self-organizing properties; they are based on local interaction of the composing elements and generating a general end-result. Digital ecosystems incorporate these features in context-aware applications that work together for the efficient solving of complex dynamic problems. This article considers the digital ecosystems as being open-system of applications with a certain degree of context-awareness. It also presents Econtxt a programming model for the context used by cont...

The sedimentary environments are in general very important aquifers because of the following characteristics: high permeabilities, storage capacity, the interaction with the surface waters. The exploitaition of this types of aquifers it is significant because, among other things, this aquifers are easily accessible (in general we don?t need complex systems of capture and in most cases are enough wells ans/or drilling between 10-100m depth). Must of the aquifers structures from the south part of Romania are usually...

The Vrancea zone is an area of concentrated seismicity at intermediate depths (60-200 km) beneath the bending area of the South-Eastern Carpathians in Romania. The purpose of the paper is first to find historic data related to the four selected Vrancea earthquakes occurred on 26 November 1829 (Mw 7.3), 1 May 1893 (Mw 6.2), 17 August 1893 (Mw 7.1) and 31 August 1894 (Mw 7.1). Next, to gather all available historic information about those events, analyze it, assess/or convert the intensity using the Medvedev-Sponheu...

Data characterizing biological productivity of wooden layer in dark coniferous forests secondary succession stands of southern taiga subzone of West Siberian continental sector have been given. Thus, the obtained data prove that ecosystems of the same age group which vary in type of root vegetation forming, developing under the similar vitality conditions (temperature, moisture and nutrition) form different organic matter stores in phytomass. The wooden layer phytomass of secondary birch stands accumulates almost ...

The article is devoted to one of developing directions in the area of improvement of construction properties with soil injection method fixative solution injection in soil under a lot of pressure the result of which happens to cardinally change structure massive soil and the formation of a rigid routinely inscribed in earth cover and forming along with compacted soil structure dubbed «Geocomposite». The method found wide application how for improve mechanical property of soils under new construction as well as soi...

The contribution is focused on problematics of the impact of weather conditions to the phenological phases of broadleaved trees (Quercus robur L., Fagus sylvatica L., Tilia cordata Mill., Prunus spinosa L.) at the selected research areas in central Slovakia. There were recorded a 10% incidence of falling and yellowing leaves on a group of ten trees selected species. Factors taken in account were rainfall data, the number of tropical days and the length of growing season (June ? August). The significant differences...

In historical city centers cobbled roadways are currently being used in the reconstructions of roads. Cobbled roadways are being built also in new construction for example parking lots, sidewalks and bike paths. Cobbled aprons are often built around a central island on roundabouts. Elevated transverse thresholds or pillows made of cobblestones are popular as elements for traffic calming in residential urban areas. A prerequisite for perfect function of these cobbled surfaces is the adherence to the correct technol...

The target of paper is the presentation of theoretical basis, methods and results of digital modeling (structural-lithological, geological-dynamic, logic-information) of heavy minerals placers for defining of their economic prospects. It is connected with need to improve methods of informational provision for researching works, aimed at involving of heavy minerals placers for the development of raw materials base of titanium, zirconium, tin, gold and other metals according to demands of pertinent industrial progre...

This paper aims comparisons of data obtained by different methods of data acquisition. Will present aspects of quality data obtained with Leica total station ultra 802, with GPS equipment from Leica 1200 Series and comparison of these data with altimetry data obtained using LIDAR technology. Measurements were made in ?ag - Par?a area, of Timi? county, on a length of approximately 4 km and over a width of 50 meters left and right from the center. Using LIDAR technology we can realize 3D models, can be detected and ...

GIS-Based Local Geomorphological Constraints Assessment (A Case Study: Cluj- Napoca Municipality, Romania). This paper deals with the implications of geomorphological constraints on urban sprawl specific to the new residential suburbs of Cluj-Napoca Municipality (Romania). In many cases, the development and the territorial evolution of the urban residential units are conditioned or restricted by the different landforms and slope processes (e.g. landslides). Cluj-Napoca Municipality area has experienced during rece...

Energetic crops are increasingly used as renewable sources of energy as well as for their ability to fix and accumulate carbon in the soil. Willow culture for biomass promotes rural development and environmental protection, especially if it is established in areas less favorable for agricultural crops. Researches from this work has been carried out in a wide range of genotypes of Salix sp. cultivated on a deposit of ash resulting from coal burning to Isalnita Power Station, near Craiova, Romania, over a period of ...

This article shows the results obtained by applying a study method of the convergence of structural models, for the particular case of a structural model from the geotechnical domain. For this purpose, is used the study method of the structural models convergence, already widely used in the field of research and CAD - CAE design. For a larger relevance and utility is presented the convergence study of a structural model for a ground section to which it applies a uniform load. The problem of ground compaction is so...

An innovative concept for design and detailing of precast concrete frame structures is analyzed under accidental seismic-type loading. The new detailing of post-tensioned assembled structures derives from the special hybrid moment frames as defined in the ACI T1.2-03 standard. The alternative detailing of special reinforcements, named modified special hybrid joints, are bondless with respect to both column and beams. The model represents a corner of an actual multistoried structure, cropped in the middle of the be...

The paper aims to solve pollution problems mining sites closed on the environmental components. In this regard it is proposed the use of microcontrollers and wireless sensors for warning exceeded limit values of environmental quality indicators. It wants to create a network of wireless sensors to anticipate the amount of pollutants to take measures to reduce pollution in the mining Brad chosen as a case study.

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, ...

Structure-independent databases are widely used in different spheres for specific tasks solving. Nevertheless, their main problem is a low efficiency that prevents them to be in progress. This work is concerned to the problems associated with data insertion. The causes of this low performance can be called the use of the existing object method of procedures creation and heterogeneity of the data insertion procedures creation process. This process uses object representation form for process of data insertion proced...

Cement manufacturing has been always ranked in the list of the main sources of carbon emissions among industrial activities. Almost 5-7% of global CO2 emissions are caused by cement plants, while about 900 kg CO2 is emitted to the atmosphere for producing one ton of cement. On this account, there is laid pressure to reduce cement consumption by the use of alternative binders. In this paper, we would like to show that wheat straw ash can be used for the fabrication of construction composites with lower cement conte...

Sustainability concerns in Romania dates back over 30 years when they agreed on the need to respond to issues raised inexorable deterioration of the natural environment, prevention of worsening ecological imbalances and ensuring ecological balance on Earth. These concerns marks the moment when humanity implicit authority of the country have begun to recognize that environmental problems are inseparable from the welfare and economic processes in general wastewater treatment plant by growing plants is a natural, ine...

The study focuses on saving energy in the process of drinking water distribution in the rural area. The hydraulic model of the water distribution network that supplies Dulcesti village, Constanta County, Romania, developed in EPANET is the basis to performing a thorough analyse of the hydraulic system?s operation. The standard hourly water demand is taken into account. The network is a branched one, widen on a large area so that the ratio is about 10m of pipe per inhabitant. The difference in junction elevation is...

The paper presents the research on the use of a waste material (a recycled powder) which partially replaces cement in fine-grained concretes. The powder was obtained in the thermo-mechanical treatment of concrete rubble, which this article describes. Roasting made a cement paste partially dehydrated and consequently activated the cement?s binding capacity. The recycled powder was tested in terms of a sieve analysis, the Blaine surface area method, density and a thermal analysis. Then the statistical experiment con...

In this article the air infiltration through the envelope of a naturally ventilated building, located in Bra?ov (Romania) is studied. The paper presents the study of the factors which influence the air infiltration ? wind effect and stack effect ? and the modeling of air change rate (ACH) inside the building, by Multiple Linear Regression (MLR) modeling. It has been found that ?T can be a good predictor of ACH because of its high physically correlation with this. Another conclusion of the study is that although wi...

The objects of the study were samples of Domanik rock from Upper Devonian siliceous-carbonate and carbonate sediments of the Romashkin? oil field, which occurs in the central part of the South Tatarian arch in Tatarstan. The composition of organic matter and mineral rock components and bitumoids extracted from them was studied by thermal analysis, X-ray diffraction analysis, SARA analysis and gas chromatography. Significant differences in the mineralogical composition and content of organic matter are found in sam...

The terrestrial scanning technology allows collecting data about an object and using it to create a 3D image of the object and then analyse it in a variety of ways, e.g. by performing an evaluation of the technical condition of a building or by diagnosing different irregularities or damages to its structure. The usefulness of such data depends, to a large extent, on the method and accuracy of the measurements. This article presents a test illustrating the relationship between different types of multicolor samples ...

Extraction of rare earth elements (REE) from mining wastes may change their physical and chemical properties thus affecting their usefulness for reclamation. The aim of this work was to assess the usefulness for reclamation of mine wastes used for REE production. Samples of mine wastes after an experimental benefication process (n=6) were delivered from Kankberg mine, Sweden. The samples were measured for organic matter (OM) content, specific gravity, maximum water holding capacity (WHC), texture, pH and electric ...

Due to their chemical, physical and mechanical properties, niobium (Nb) and tantalum (Ta) are strategically used in various technical applications. About 130 different minerals contain tantalum and niobium, of which only about 80 are found in economical deposits. The remainder contains Nb and Ta as impurities. The most commercialised source of Nb and Ta is a columbite-tantalite ore often referred to as coltan containing pyrochlorite. The Central African Mesoproterozoic Kibara belt in Katanga (Democratic Republic o...

Water filling of remaining gaps of lignite open-pits are used frequently worldwide, is economically acceptable, having long-term benefits, regardless of the use of pit lakes. Choosing this type of use leads to appearance of a water surface, which may increase, for example, the ecological, productive, cultural value of both the landscapes and terrains. However, not every remaining gap can be flooded for extremely diverse reasons (slope stability issues, climate, regional development strategy, etc.). The paper propo...

In the Czech Republic there is a dramatic deterioration in the construction condition of the culverts. This development was signed by defects caused mainly by traffic from overloaded vehicles, traffic growth, atmospheric effects, chemical effects caused by salting in the winter time, construction type of culverts and age of culverts. One of the most important factors is insufficient pursuance of evidence culverts and construction maintenance, e.g. remove defects occurring in the beginning [1]. The paper deals with...

The Committee on Affairs of construction and housing and communal services of the Ministry of national economy of Kazakhstan approved the "Scheme of water supply and sanitation Kyzylorda", which is represented by the following decisions in choosing a water supply source. So, according to the first embodiment of the solution, the scheme drinking water supply was provided from two groundwater sources: Kyzylorda and Ky-zylzharminsky fields located on the right Bank of the city. Supply and return water was provided th...

The tomatoes are widely spread on all globe because the fruits have an important content of carbohydrate (2.9 - 7%), vitamins (A, B, B2, B6, C), salts of important mineral elements (K, P, Fe, Ca, I, Mg) and organic acids (0.5-1.5%). They are considered one of most important vegetable crops. The Romanians have classic options about the vegetable taste; they appreciate tomato with superior organoleptic qualities, the ?taste of Romanian tomato?. In Romania, the aim is the propagation and the cultivation of Romanian t...

Since 2014 Russia has been developing and implementing a new environmental policy based on the concept Integrated Pollution Prevention and Control and Best Available Techniques. Transition to Integrated Environmental Permits is gradual: first 300 industries characterized as ?key polluters? have to obtain permits in the period of 2019-2022. They will be followed by at least 5-6 thousand industries of nearly 30 economic sectors. Within the construction materials industry sector, several older cement plants are liste...

Contemporary life is characterized by a state of continuous change and that?s why standard solutions are no longer the key to all problems. Like many other fields, architecture seeks new alternatives to overcome the challenges we are facing on daily basis. Sustainability is one of the many issues that concern us, trying to solve some of the problems that globalization generates. On this line, one of the directions is a definition of architecture as landscape: topographical architecture. Topographical architecture ...

The methodology of computer simulation of nonstationary fields of temperatures, concentration and pressure is considered. The computer model of non-stationary heat exchanging process is researched. Decentralization interaction of the active parallel agents is the base for computer implementation. Agents are defined as abstraction of elements of physical system where the modeled processes proceed. Process characteristics are calculated on the base of information on non-stationary fields of temperatures of a wall of...

In recent years, membrane technologies combining advantages of biological treatment and membrane filtration have been well advanced in the world practice. Application of an anaerobic membrane bioreactor (AnMBR) for wastewater treatment could be an attractive alternative to recover energy in terms of biogas. The article presents the results of laboratory tests on water treatment in an anaerobic membrane bioreactor with an external hollow fiber module (PVDF). Researches were performed on wastewater of a pulp and pap...

The objective of the paper was to emphasize the influence of the biological activity on the structural improvement of the compacted clayey pedogenetic horizons of two Chromic Luvisols, by the organic matter bioturbation. The researches were performed on two Chromic Luvisols from Romanian Plain, where the mean annual temperature is 10.5oC and the mean annual precipitation is 548 mm. The analytical data showed that clay content increased from the top layer of both soil profiles (28.9% in P1, and 29.8% in P2), to Bt ...

This paper is focused on the simulation using Matlab/Simulink software? of the Photovoltaic (PV) cell/module/array for a better understanding of the power generated under different atmospheric conditions (irradiance and temperature). One diode model and double diode model of a PV cell are also shown in this paper. The simulations could be performed considering both models, but here only the PV caracteristics for one diode model will be shown. The resulting model uses a friendly interface considering the Function B...

In Turkey, it is essential to use agricultural land efficiently by obtaining more harvests from unit area in order to afford the increasing population needs on food supply, generate higher revenue from agriculture, and develop country. In doing so, the key movement is the practice of land consolidation. Land consolidation studies, which started in 1961, have been mainly aimed at linking roads and irrigation networks by clustering amorphous, scattered, fragmented, and small agricultural lands. As gaining momentum i...

Revealing the conditions and mechanisms of evolution of oil deposit based on optical and electron microscopy, electron paramagnetic resonance (EPR) is a necessary step to create improved of recovery methods. Application EPR for study temperature, mechanical and radiation dynamics of organic matters were presented in this communication. The subject of the investigation was the core material from Bazhenov suite (East Siberian oil and gas province). In order to reveal the features of the material composition and the ...

The coal-fired power stations are particularly complex polluting agents, furnishing simultaneously, high and low environmental pollution sources, through the chimneys for burning gases evacuation and the ash dumps, respectively. The Deva-Mintia coal-fired power stations has an installed power of 1260 MW, six power units of 210 MW each group having two steam boilers of 330t/h, the energy being produced by the coal extracted from Jiu Valley mining area. Coal-fired power station Mintia is located in South East Transy...