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The present paper concretises a current assessment of the quality of the environmental components by characterizing the soil and groundwater samples in 4 agricultural areas in Romania, chosen as case studies according to the criteria of their vulnerability to climate change. The important data obtained from laboratory physical and chemical characterization of soil and groundwater samples taken from these areas, have been analyzed in close correlation with current agricultural practices identified and their local s...

The aim of this article is the studying of the "predator-prey" populations controlled interaction. The well-known Lotka-Volterra system ([1], [3], [5-15]) with control is used as a mathematical model. A complete research of this model is done: from its parameters identification to the choice of optimal control. The identification numerical algorithms are based on the Taylor series method. This method application is reasonable in this case, because right sides of the considered ODEs system can be presented in polyn...

As a result of mining activity on the earth?s surface the phenomena that have negative effect on the objects in area of influence of extracted area exist. Depending on geomechanical qualities of hanging wall and surrounding rocks, geological conditions of depositing, seam and depth of position of deposit, critical angle of influence, way and time course of mining and other parameters the horizontal and vertical movements always appear to a greater or lesser extent. They can be described by inclination, proportiona...

One of the most effective ways to interpret the geological setting of a deposit is building its 3D model. Presenting data in form of a 3D model enables quick and convenient access to relevant information, facilitates taking decisions associated with deposit management and helps plan mining operations. With a model of the geological setting of a deposit it is possible to prepare different variants of a coal mine model as well as type of mining technology, to tackle work-related safety issues and to achieve optimal ...

We consider a problem of reservoir facies classification based on well logs. The classification procedure assumes that there is a train sample, which has a corresponding lithotype for every log entry. Since the physical nature of observed rocks is very complex, there are currently no adequate mathematical models which can describe it. We proposed the probabilistic model which takes into consideration mutual stochastic dependence of adjacent log entries, which is represented by Markov networks. The characteristic f...

In this paper we present a case study on the identification and contouring of a gas deposit, placed mainly in Pontian formations. This study is based on some geological landmarks as well as the interpretation of filtered gravimetric and magnetometric data. The gas deposits determine minimum gravimetric anomalies, under the specific geological conditions of the Transylvanian Basin. Such gravimetric minimum is determined on the one hand by the rise of the salt, and on the other hand by the mass deficit within the sa...

As an effect of globalization on natural resources demand, the need for an increasingly detailed knowledge of the geological structure of a territory and of the characteristics of these resources have also emerged. This has been the context when the administrative boundaries and the specific national policies and legislation have differentiated the current knowledge of a geological unit. For the authors of this paper, the western part of Romania is the most recent case studies where the harmonization of Romanian g...

More than thirty percent of deaths from stroke, lung cancer, and heart disease are due to air pollution. Due to the current economic global situation where half of the world has no access to clean energy, furthermore, it seems highly unlikely that IC engines will go out of business anytime soon, we face the reality that our engines will continue to pump out harmful emissions. The main pollutants are particulate matter, a mix of solid and liquid droplets arising mainly from fuel combustion and road traffic. Thus, w...

For increasing the volumes of the grain production and quality it is necessary to restore and extend sowing area, enlarge the yield growth at the expense of intensive technologies of cultivation, effective selection and decrease of losses while harvesting. One of the main reasons of yield shortage is lodging of sowings. This paper compares extent of grain crops lodging. The investigation was carried out using mathematic analysis of variety features of the stem resistance for winter and spring wheat, barley, rye, t...

In this publication, we summarize, systematize and analyse data collected for studying the use of HTTPS in the public sites of banks in Bulgaria and Serbia. The scope of the study is limited to the public site of the particular bank. We examined the web sites of all 20 banks licensed in the Republic of Bulgaria and 27 Serbian banks licensed by the Serbian National Bank at the time of the survey. The survey excludes the foreign bank branches operating in the respective countries. The main objective of the study is ...