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The Dolj District is located on Oltenia Plain in the southern part of Getic Plateau. The studied territory which is the northern part of Dolj District is located on the central zone of Oltenia on the high plateau Leu-Rotunda. This area is characterized by varied natural conditions and so is the formation phenomenon of soil. As a result of soil formation factors, within the northern part of Dolj District there were formed soils that have as specific horizon the clayey one, the most encountered being preluvisoils. T...

A starting point for roadheader robotisation (understood as a fully autonomous machine) is to automate the cutting process, which is the basic working process carried out by such machines. In case of boom?type roadheaders, it consists in automatic control of the movement of cutting heads to ensure that the face surface can be worked with optimum process parameters. This will guarantee high drilling efficiency (drilling advancement) and lower energy consumption, reduced dynamic loads and elimination of overloads. T...

The study pertains to a regional and local context of the adaptation to climate change and explores the main international and European Union decisions in this regard, as well as the goals set for Latvia. The concept of adaptation is clearly connected with the drafting of sustainable development policy and must be handled at different levels. The study analyses the examples of international and local projects used in the situation of Latvia and the documents drafted by local governments, facilitating implementatio...

A novel image edge detection technique is proposed in this paper. The considered boundary detection approach uses a nonlinear parabolic partial differential equation (PDE) - based model. We develop a nonlinear anisotropic diffusion scheme consisting in a second-order parabolic equation and some boundary conditions. An effective edge-stopping function is constructed for this PDE model. Then, we construct an explicit iterative numerical approximation scheme for this model, by using the finite-difference method. This...

Both complicated dissolution processes and different patterns of fossils? distribution may be expected in carbonate hydrocarbon reservoirs. Therefore, this paper aims to precisely locate such places using few independent analytical tools. Five carbonate samples from the Permian Bro?sko Reef (Western Poland) were studied in a form of both thin sections and cylindrical core samples. The latter were subjected to Computed Microtomography (?CT) and Nuclear Magnetic Resonance (NMR) experiments. While the ?CT helped to p...

The scientific paper deals with the multi-criterion optimization of the teeth that are used on the buckets of bucket wheel excavators. From past theory and practice, it is known that geometry of the tooth greatly influences the cutting parameters and the endurance and the strength of the tooth itself. The dependencies between the cutting forces, the penetrating forces, the specific energy on the rake angle and the relation between this last one and the robustness of the tooth are somewhat contradictory, so in the ...

This article discusses typical problem of industrial floors, i.e. cracks. Slight cracks are usually effect of volume changes such as shrinkage and creep. There are also other reasons why cracks appear. For example: inappropriate design, heavier load than expected or wrong realization of the concrete slab. Cracks, which are caused by mentioned reasons, are wider and deeper. Wide and deep cracks can cause another defects such as concrete crumbling along the crack. They can be a problem for maintenance and service li...

Many oil and gas low permeable reservoirs have been stimulated to enhance productivity. Acid fracturing is one of the commonly used well stimulation treatment in carbonate formations, such as limestone, dolomite, and chalk. Carbonate reservoirs are good candidates for acid fracturing since strong acids such as hydrochloric acid react easily with carbonate. The acid reacts within the fracture to create a differentially etched surface that will maintain a conductive pathway. Habitually, a pad fluid is injected ahead...

In this contribution, the authors describe a novel method of visualizing any 3D object into a 2D seamless picture with the use of cartographical principles. The method uses properties of a sphere with reflective inner surface, in which a 3D object and capturing camera are placed. A sphere surface is consequently unfolded using cartographic projection allowing to see the whole object in 2D. The method can be applied to any objects, preferably those of non-human origin, e.g. trees with leaves, cave systems, Earth?s ...

The paper considers the issue of effective scale inhibitor applied while developing an oilfield using steam assisted gravity drainage technique, and presents a case study of injecting superheated steam of 140-160?C in the Ashalchi oilfield. In such conditions, organophosphorus chelating agents conventionally used to prevent scale formation degraded and proved to be ineffective. The authors analyzed chemical composition of scales deposited on the electric submersible pump pulled from one of the wells in the Ashalch...

The paper deals with plant growth-promoting rhizobacteria and their capacities to boost the efficiency of phytoremediation processes applied on soil polluted by the industry. For this purpose, we chose a locality in the form of decontamination site in Ostrava, where ruderal plants were sampled. Such plants are generally regarded as hyperaccumulating with high production of biomass plants. Their root systems were confirmed for the occurrence of PGPR-bacteria, predominantly of the Pseudomonas genus. The results of t...

This work was interdisciplinary, so the data provided by the measurements went into the Central Park rehabilitation project, providing graphical support for architects, structural engineers, plant engineers, specialists in landscaping. Baile Herculane is a famous Romanian resort which is located in the south - eastern county of Caras Severin, along the tectonic corridor Cerna Valley, which separates the Mehedinti Mountains from the Cerna-Godeanu Mountains. The Central Park related land is owned by the City Council...

The paper focuses on investigation and evaluation of the existing situation of various types of brownfield in the field of their technical installations. These brownfields are investigated typologically and divided according to their types, sizes, and functional utilization. This is the base on which their technical attendance is evaluated, namely the designs of public utilities and traffic infrastructure, not only inside the premises, but also the assurance of their connectivity from the point of view of deeper r...

Pesticides alter the biological properties of the soil, leading to a complete loss of their fertility. Chestnut soils (meadow brown, light brown) are resistant to contamination by pesticides and by fertilizers in particular. We have carried out studies on the effect of the examined soil pollution with high doses of fertilizers and pesticides on the soil mesofauna representatives. The work is based on studying influence of anthropogenic impacts on soil biological activity in comparison with its main indicators, whi...

Schemes of mining and construction operations have been developed for inclined trenches on the open pit edge, where transport platforms and safety benches using the drilling and blasting method of rock mass preparation are located. The volume of mining operations is calculated taking into account the dislocation of a part of the open pit edge of the deep open pit mine for placement of loading points at the bottom of inclined workings. A new scheme of conducting mining operations implementing steeply inclined conve...

Evaluation of explosion-proof protected electrical equipment in scope of certification is extremely important considering the risk of explosion that has to be minimized in order to ensure life safety and health of workers and to prevent damaging of property and the environment, as well as free movement of goods when they meet the essential safety requirements at European level. The purpose of this paper is to present the tests carried out on the cable entries with type of protection increased safety and flameproof...

The article is an introduction to the issues of shaping the areas of former lignite mining surrounding the city of Zielona G?ra (Lubuskie voivodeship, Poland). The city of Zielona G?ra, seeking new investment areas, develops further areas, including those that have been former mine sites for at least 70 years. They have never been reclaimed. The remediation of former lignite mines, both technical and biological, is the responsibility of the mining plant and should be carried out in accordance with the law, however...

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...

When it comes to workplaces characterized by a high degree of hazard and liability, such as mine intervention and rescue in major risk environments the most important element is the convergence of the skills required by job and skills of the individual, this being the guarantee of successful vocational selection. Along with psychological selection, training / retraining and physical training in conditions as close as possible to the reality of future interventions, under the action of stress factors that cause neg...

According Act No. 157/2009 Coll., on mining waste management, the Czech Geological Survey carried out a project of the Operational Programme Environment in 2010?2012. The project was entitled ?Investigation of closed and abandoned mining waste facilities posing a serious threat to the environment or human health?. The aim was to create an inventory of hazardous mining waste facilities and to develop a methodology for their assessment. In the Czech Republic, 300 potentially hazardous mining waste sites were identif...

There are already numerous attempts to scientifically relate seismicity to a number of precursors in seismologically active areas. There are also attempts to identify phenomena that may trigger the seismic events, especially the high magnitude ones, such as active tectonics or the Sun ? Earth ? Moon gravitational interactions. When studying the ROMPLUS Earthquake Catalogue [1], the time variability of seismicity in the Vrancea zone, characterized by both crustal and intermediate depths earthquakes, the results sho...

Humid and arid climatic cycles during Sub-Atlantic time in the forest-steppe area of the East European Plain were studied based on soils buried under archaeological sites of different time. The shift of the boundary between steppe and forest patches is recorded in the shift of the studied soils: Luvic Greyzemic Fhaeozems of the forest patches and Luvic Chernozems under steppe environment. The complex research is based on archaeological investigation, assemblages of morphological (marco-, meso- and micromorphologic...

Gas field redevelopments or rehabilitation projects have become an alternative approach to develop incremental production and additional reserves using new fit-for-purpose technology and concepts. The integrated reservoir study begins with geological characterization and modeling followed by evaluation of the geological gas resources and reserves considering the actual production profile. The redevelopment plan continues with a well by well review and nodal production system analysis to evaluate well performance a...

At present, scale control through chemical inhibition is the preferred method in oil recovery though the principle of chemical agent action is still considered complex and not fully understood. An important issue that needs to be addressed is associated with compatibility of techniques and their impact on the reservoir and borehole zone. Scale control solutions remove deposits effectively and inhibit their formation, reducing costs associated with scale cleanup and disposal, while helping increase production and p...

The paper presents a method for authenticating images that were shot using a mobile phone. Thanks to the newest advances in integrated cameras, smartphones represent one of the most popular ways to take a photograph. A picture could be critical evidence in a trial and, with the abundance of free editing software, a forgery is easy to achieve. A method to secure and test photographs for authenticity was developed, implemented as a mobile application, tested and detailed in this paper. The watermarking algorithm is ...

The performances of the excavation machines depend largely on the tool and overall machine characteristics and on the other hand on physical mechanical characteristics of the excavated rock. There were more theories based on analytical deductions to explain the main cutting parameters on the basis of basic physical mechanical properties of the excavated rock. In this paper we use a new methodology, based on reliable laboratory data, which make possible to obtain correlation and regression formulas in order to pred...

Geographic information is a huge volume of cartographic and geographic data, which is represented by the records, coordinates and attributes. According to the Handbook [2], geographic information is fractal with very simple geometric properties, is fuzzy, because it models a part of the physical world, is very dynamic, due to the rate of change, is unique and it contains errors. The most often medium, which displays geographic information is map, no matter if it is in analogue or digital form. The whole production...

In Banatului Plain area (western Romania) the grassland vegetation is represented by steppe and forest steppe. From the past, most of the land was cultivated and nowadays grasslands are present in the plain only in the vicinity of the inhabited area for the use of the grazing animals of the community during the vegetation season. Many times the steppe grasslands are characterised by an increased alkalinity of the soil that determinates the existence of the halophytic vegetation sward. The plain is mostly intensive...

The research was aimed to study the pore water volume and chemical composition in the isolated core samples of the Bazhenov source rock formation taken from four different oil fields in West Siberia, Russian Federation. The approach is based on the complex laboratory methods of the investigation such as Dean-Stark and evaporation methods, the X-ray spectrometry, mass-spectrometric study (ICP-MS), water and Pfeffer's solution extracts. It was found that the samples contain three types of pore water: free groundwate...

Nowadays, renewable resources come to the forefront in the production of electricity. Among the most important resources belong the utilization of hydropower potential of water courses. The construction of hydraulic structures should not have a negative impact on the groundwater level regime of the surrounding environment. In the article, we focused on the selected small hydropower plant on the Hron River. There was built an effective monitoring system to track changes in groundwater level regime during its constr...

In the latest decades, wooden structures have known a significant revival in the context of sustainability challenges, considering the low-embedded energy, low carbon impact of this renewable resource. The employment of modern wood structures presents many economical advantages as well, from the availability and the low-cost of the material, to the ease of processing and construction. An important aspect is the energy-efficiency of the system in exploitation, when we consider life-cycle assessments. Light-frame co...

Pectinatella magnifica is freshwater organism, which round-shaped colonies are most often found attached to the different submerged parts of coastal plants and can reach the weight even several kilograms. Usually it can be found in oligotrophic to mesotrophic waters, during the season when water temperature reaches 20°C and more [4]. Although Pectinatella magnifica originally comes from North America, it has recently been known as an invasive species in Europe and part of Asia. The first recorded occurrence in Eur...

The use of closed water rotation in enterprises processing phosphorus-containing ores requires a long standing circulating water precipitation in the tailings storage. The paper studies possibility of treatment of industrial mineral processing waters from suspended particles and water-soluble impurities adversely affecting the flotation process with the help of reagents-flocculants. The characteristics of the dispersed and liquid phase of industrial waters formed during the processing of non-sulfide ores (for exam...

The most important geophysical problem is the inverse gravimetry problem. The problem is in finding an interface between two layers with different densities using known gravitational data. This problem is described by a nonlinear integral Fredholm equation of the first kind; so it is ill-posed. After the discretization of the integral operator, the problem is reduced to solving a system of nonlinear equation. For large grids, it is necessary to develop parallel algorithms for multiprocessor computing systems. To s...

Each building structure is rested on the foundation surface, so it is necessary to analyze these structures in interaction with subsoil. From the historical viewpoint, the most used is the Winkler model. Later two-parametric models of subsoil had been introduced, implementing the effect of shear forces and impact of subgrade around the foundation into the calculation. Other models are based on the theory of elastic half-space. The use of FEM introduced a lot of advantages to model structures in the interaction wit...

Survey sketch is a technical base for legal matters and base for changes cadastral operates. Sketch provides a system where individual digital and analog elements are interconnected through distinct indicators employing principles of modern relational database. The current state analysis of making of survey sketches indicates several technological inconsistencies. The goal this paper is to propose a comprehensive system which combines relational connections between analog and digital parts of survey sketches with ...

Piled raft is a recent innovative foundation. The superstructure loads are transmitted by piles and raft. It provides safe and economic foundation. In this paper, the influence of raft-subsoil interaction on a lateral behavior of the foundation was investigated. Three-dimensional models of the piled raft and pile groups were developed by ABAQUS program. Then, their lateral deflections were compared. A gap between the cap and subsoil in pile group was varied from 0.25m to 1 m. In addition, the pile spacing was chan...

It has been statistically proven that tuffogenic sediments, especially tonsteins, have a negative impact on the incidence of pneumoconiosis (silicosis) among miners in French coal basin. Therefore, the rocks attract the interest of geologists not only due to their origin and possibility of use for correlation purposes, but also as a source of dust hazard in mines. The present publication presents mineralogical tests of inhalable grain size dust formed during the exploitation of a coal seam with a tonstein overgrow...

We have collected paleomagnetic samples from Late Devonian (Fammennian) basalts and sedimentary redbeds at the Bykovskaya Straight (in the vicinity of Lena River delta). Most studied samples carried interpretable paleomagnetic signal. Three paleomagnetic components have been isolated: A+A?, C, and D. The magnetization of the overwhelmed majority of Late Devonian samples from the Bykovskaya Straight has been reset by modern (or Late Cenozoic) geomagnetic field (component A+A?). The sole site was characterized by th...

The ecological situation of the Arctic and sub-Arctic areas has been given special attention due to their extremely vulnerable environment. In comparison with other areas, the Arctic remains a clean environment, but heavy metals occupy a special place among priority pollutants. There are a lot of studies of heavy metals in the soil, but not enough information on the joint content and physicochemical factors that affect the metals accumulation in the Arctic soils. Therefore, this paper presents identification of co...

In this paper the properties of level surface of potential of gravity arising in the generalized problem of two centers are investigated. Interest in this research is related to the desire to use the opportunity of an analytical approximation of the Earth?s potential through the potential arising when solving the generalized problem of two centers (intermediate Earth?s potential) to modeling the Earth's surface. Further, for a such approximation the level surface of potential of gravity arising in the generalized ...

We analyzed the dynamics of Lake Teletskoye water level and attempted to use data on bottom sediment geochemistry in combination with Siberian larch (Larix sibirica) tree-ring width chronology to reconstruct it for late Holocene. In particular, we studied the links among the water level characteristics, precipitation amount, bottom sediment geochemistry, and tree-ring width chronology available for Russian Altai. A correlation analysis revealed the annual water level fluctuations to correlate closely with mean ann...

This article defines the requirements for the architecture of the planned state satellite geodetic network, mathematical models (used in the processing of GPS measurements), navigation modules and analyses the possibility of integrating the high-precision geocentric coordinate system of the Republic of Kazakhstan with the global terrestrial system of the ITRS / ITRF. The main goal in solving problems of high-precision satellite geodesy is to determine the exact coordinates of the SGN point by processing code or ph...

Usually the frost heave of soils causes damages to low-rise buildings, road paving, and pipelines. However, a few years ago unusual deformations of a building supported by 18 meter piles were found. It was a cooling house designed for fish storage at the temperature of -22?-24°?. The building was 8,4m high; its plan dimensions were 24?42m. To protect the ground against the frost penetration a 0,9 m layer of light gravel under the concrete floor was filled and an electrical heating system under it was set up. The b...

The paper presents an automatic sorting process of different color pieces. This paper is the result of a multidisciplinary depth study focused on industrial automation field more specifically on robotics, informatics, or control of the flexible manufacturing systems. The hardware and software system is formed by a robotic arm, a color sensor, sensors, a conveyor, a system of outlet cubes and a storage system, a transporting system for the robotic arm. The goal of this paper is to remove cubes from the deposit use ...

This paper evaluates the abnormalities in monthly, half-year and annual rainfall totals in the Western Tatras Mts for the period 1994 to 2013, issuing from the values recorded at the precipitation stations Bobrovec situated at 632 m a.s.l., Zuberec at 763 m a.s.l. and ?ervenec with an elevation of 1,500 m a.s. l. These stations have also different exposures as for the dominant wind flow: Bobrovec is situated on the leeward side, Zuberec on the windward side and ?ervenec in the summit part of this mountain range. T...

The dynamic development of material and chemical engineering as well as physical analytical methods allows the use of new materials for the production of drilling muds. This is especially important because drilling works are conducted in increasingly difficult geological and technological conditions. The present analyses concentrate on the development and elaboration of recipes of drilling fluids with organophilic nanomaterials. One of the most frequently applied nanomaterials referred to in patents registered by ...

The risk assessment of an organization is stipulated in international standards and in a variety of international and national laws and reglementations. In the context of the obvious environmental problems and incidents with disastrous effects for the environment of the past 50 years, industrial and business environment recognizes the importance of environmental risk management and its applied. In the process of the environmental risk management, the risk assessment and risk treatment plays a crucial role in the c...

The ever-increasing demand for heating in different sectors, along with more preventative regulations of greenhouse emissions, has forced different countries to seek new alternatives to heat buildings such as district heating system (DHS). DHS is best suited to areas with a high building and population density in relatively cold climates. District heating, considered as the most efficient method for building space heating, has been dramatically developed over the past decades. This paper approaches the description...

Apatite is mineral - common name for a number of related minerals of the apatite group with the common formula Ca5(PO4)3(F, OH, Cl). Mmineral species in the group are fluorapatite (F - up to 3.8), chlorapatite (Cl - up to 6.8), hydroxylapatite, carbonate-apatite. Kola apatite concentrate is a promising and raw material for complex processing, allowing to produce, in addition to the basic product ? phosphoric fertilizers, strontium, rare earth elements and fluorine compounds. Despite obvious environmental expedienc...