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Metal Oxide based Varistors are basically ceramics, acting as n ? semiconductors, having a poly-crystalline and dense structure. The main application of these power electronic devices is for construction of overvoltage protection equipment (for every voltage level), because of some advantages like: an increased level of non-linearity between the current and the voltage characteristic, a high energy adsorption capacity and an excellent good response time, which make them ideal for protecting other sensible electron...

In-Situ Combustion is one of the most important and promising methods for enhancing oil recovery for both light and heavy crude oils from reservoirs. In this method air is injecting into the oil reservoirs and causes ignition and in the next step it effects combustion inside of reservoirs. Nuclear Magnetic Resonance (NMR) spectroscopy as a fast and accessible technique was used to monitoring the light and heavy crude oils oxidation behavior. Herein, we investigated two light and heavy crude oils based on temperatu...

The cereals (especially, wheat) production increases in all regions of the World. However, the challenges of sustainable development and the demand for products with increased added value make the use of the entire crop for food unsustainable. Alcohol fermentation of grain by yeasts is one of ancient technologies created by mankind. Highly productive fermentations of lactobacilli and even bifidobacteria can be carried out also. A significant change of the approach is necessary as these bacteria are sensitive to th...

The cereals (especially, wheat) production increases in all regions of the World. However, the challenges of sustainable development and the demand for products with increased added value make the use of the entire crop for food unsustainable. Alcohol fermentation of grain by yeasts is one of ancient technologies created by mankind. Highly productive fermentations of lactobacilli and even bifidobacteria can be carried out also. A significant change of the approach is necessary as these bacteria are sensitive to th...

This article summarizes the findings of extensive hydrogeological mapping that has taken place over the past few years. The area of the CSA mine is situated at the northern edge in the central part of the Most Basin (North Bohemia, The Czech Republic). The area of interest is divided into several hydrogeological units, which are characterized by mutually different main determinants such as morphology, lithological characterization of the main types of rocks, tectonic violation. These are the following units: the c...

Formation invasion plays an important role in the modern drilling practices. The well completion and production cost play more and more important role as the petroleum industry meets new challenges. The well completion and stimulation cost can be reduced if the mud?s effect on the hydrocarbon-bearing formation is clearly known and can be modeled at the well design phase. Better mud selection leads to lower cost in the completion phase. Proper mud selection can be supported by early reservoir analysis based on prev...

The world leader artificial lifting method is sucker rod pumping when considering the lifted well?s number. However, those sucker rod pumped wells are mostly stripper wells. The optimal production of stripper wells is a key-question in the life of mature oil fields close to abandonment. Sucker rod pumping is a well-known technology however production optimization and continuous operation supervision are essential for the economical production. The economic considerations are more powerful limitation factors for st...

The last decades witnessed an explosive increase of the demand for digital data in the economy. This led to a significant growth in the number and the sizes of data centers. The energy used by the data centers has increased dramatically. This situation determined the quest for metrics that measures energy efficiency in data centers. A classical metric for measuring energy efficiency in data centers is PUE (Power Usage Effectiveness). It was introduced in 2006 by C. Malone and Christian Belady. It is defined as the...

Out of allbroad-leavedspeciesthat are to be found in our woods, ash trees have a special importance throughboththe great value of the wood andthe cultural qualities.The imbalancesin forest ecosystems due to the influenceof some climatic and anthropic factors havematerialized in the occurrence of some gradations of defoliationinsects, among themStereonychus fraxiniDe Geer, 1775.In the last few years the ash tree stands were increasinglyaffected, which requiredeven more careful preoccupation withthe prevention and c...

The ambition of universities is the implementing of new progressive teaching methods using state-of-the-art technical equipment. The general aim of modern teaching methods is to provide students with the widest range of information channels that can be used to obtain information and data. Students are specifically challenged to use this information. Based on this, students acquire their gained knowledge. This modern model prefers current pedagogy. One of the projects focusing on new trends in teaching is the proje...

This paper deals with new trends in fire testing of electrical cables. At present, the most widely used tests of electrical cables are reaction to fire tests. The cable systems powering electrical devices which have to remain operational for a certain period of time under fire conditions are additionally subjected to circuit integrity maintenance testing. New trends in cable fire tests include tests of critical heat flux, testing the effect of cable inclination, current load, voltage and frequencies to the rate of...

Distance learning has become increasingly popular today. It is defined as the process of transferring knowledge to learners (students) who are separated from the instructor (teacher) by time and / or physical distance and are making use of interactive technologies to accomplish learning. Krasnoyarsk state agrarian university also uses distance learning. Both teachers and students of our University benefit by the introduction of distance learning technologies in the educational process. Students can take part in on...

The article presents a comparison of the advantages of natural refrigerants R717 or R744 (with low global warming potential ?GWP and zero ozone depletion potential ? ODP) instead of R404A. Energy Efficiency is also analysed. Romania signed Kyoto and Montreal Protocol and in the same time as a new member of EU has the obligation to respect the environmental legislation as Energy Efficiency Directive, Eco-Design Directive, and Regulation 517/2014 cold ?F-Gas? and to solve Certification System in the field of Air Con...

Amines are the key intermediates for agricultural, pharmaceutical, textile, polymer industry etc. The common method for the amines production from the fossil resources, in spite of the high yield of the target products, is characterized by the high amount of side toxic products. Nowadays the production of bio-based amines, in particularly the derivatives of sugars, is of the growing interest. This route of amine production results in the minor waste formation and can be considered as a sustainable. Among various r...

In this study, investigation of the composition, structure and catalytic activity of the catalyst support based on Ni-Al mixed oxides was carried out. The possibility of controlling structural and acid-base properties of the layered double hydroxides (LDH) by varying the ratio of M2+/M3+ metal cations determines its use as catalyst support. Besides varying of anions in the interlayer space allows to regulate catalytic system activity in the reaction medium. The Ni-Al LDH support was prepared by coprecipitation met...

Vegetation takes the active part in processes of migration and transformation of chemical combinations on the Earth's surface. The intensity of biogenic migration of chemical elements is defined, first of all, by chemical composition of plants. Various security of soils with chemical elements causes also their various accumulation in agricultural plants. Unrationed use of fertilizers, pesticides, broad development of the industry in the territory of the studied region - all these factors allow to classify the Rost...

One of the main contaminants in groundwater of South Russia is nitrate and being one of the essential problems of water providing system needs a solution. It was in 1981 when World Organization of Health pointed on necessity nitrate studying soil and water. Estimation of nitrate contamination in groundwater, used in housekeeping, of Rostov region was held. Results give an opportunity to find out and estimate tendency of changing quantity of contaminant in groundwater and can be regarded as foundation for further e...

The main factor of effective biological waste water treatment and pollutants biotransformation is correlation between different nitrogen forms in the media. The waste water specimens were obtained from the pulp and paper mill of the Russian North involving BAS-technology. Concentration of ammonium ions in wastewater was carried out on a spectrophotometer by Sedji-Solorzano method using phenol-hypochlorite reaction. Nitrite ions were determined colorimetrically by diazotization with sulfanilamide and subsequent cou...

Mixed intercropping of cereal-leguminose presents important tool to increase efficiency of using nitrogen from soil and fixing it from air while current recovery of soil fertility. The paper presents first results of a field experiment after its start in 2012. The main goals of a presented study were as follows: (a) to describe setting and assessing the results of the experiment in the system of mixed cereal-legume culture, (b) to investigate the utilization of N in the mixed culture of winter wheat and winter pea...

Seismic sources location is one of the main tasks of seismology (determination of earthquake hypocenters) and this is the main task in microseismic monitoring of hydraulic fracturing. When choosing a method for microseismic monitoring, noise immunity is one of the main parameters, which should be considered in order to obtain reliable results. The article is referred to the location of a point seismic source by the Diffraction Stacking method applied to synthetic signals obtained using 2D numerical simulation of s...

Zones 30 have been used for years in suburban districts as common traffic calming devices. The solution of zone 30 was used in a street in Szczecin. The street connects the area of detached houses with large panel housing estates. To reduce speed to 30 km/h, four successive raised areas were made of paving stone cubes as well as a 1 m wide median strip in the road axis. The change of asphalt blanket into paving stone cubes is thought to change the acoustic climate, due to differences of noise levels generated by t...

The right selections of BHA, (bottom hole assembly), provides to minimize cost of drilling through the elimination of fishing works, which could took place during drilling. In many cases during drilling operations there is need to maintain the continuity of pure drilling works in the wellbore through fishing works. The name of the time for these works, it is known as NPT ? nonproductive time. Before drilling the borehole, the engineers must took into account all geological properties and affordable technological s...

The paper is considering the results of the development of three hundred and three deposits of the Romashkinskoye oilfield, which is composed of porous fractured carbonate reservoirs. The investigation was devoted to the challenges associated with increasing of the production from the carbonate reservoirs on the basis of study concerning the conversion degree of the reserves involved in the development and production through the non-stationary production well operation. The authors present a comparative analysis o...

Nowadays, landscape specific agriculture development, along with precision farming, is one of the most promising areas for improving crop production worldwide. At the same time, further farming systems improvement should be based not only on the latest achievements of traditional fields of agronomical science, but on some of the interdisciplinary researches, that make good use of the results of modern scientific research. The study addresses the results of the scientific study on the development of the normative-r...

A number of small mountain ranges (horsts) separated by small basins (grabens) with Tertiary sedimentary filling appeared in the Western Carpathians mostly in their NW and N part. The Tatry Mts. and smaller so called Ru?bachy ?island? are the northernmost horsts from a series of Western Carpathian horsts. Our magnetotelluric measurements focusing particularly on the nature of the Sub-Tatra fault and the interconnection of the Tatry Mts. with the Ru?bachy ?island? confirm steep dip of Sub-Tatra fault in the souther...

At present many new housing projects are being realized in Poland. They are often built in areas characterized by complex hydrogeological and geotechnical conditions. In such cases, the need to build deep excavations is complicated, especially when there is a high water table. The paper presents analysis of dewatering process of deep excavation of residential building. The excavation was carried out to the depth of 10 m below the ground surface. Due to the location of the investment near the river the water table ...

The purpose of the present paper is to analyse the behaviour of a flexible pile foundation versus a rigid one when submitted to lateral cyclic action coming from waves or wind, through numerical modelling using 3D finite elements. The comparison elements are: the maximum pile head displacement and the evolution of the maximum bending moment. The numerical modelling has been performed using the software CESAR-LCPC [1]. The study has been performed for 15 cycles, but the numerical model has also served to create som...

Antropogenic seismicity is one of the most important geomechanical hazard encountered in Polish deep copper mines. Obviously, it may have a negative impact on the people?s safety and the production process. In such circumstances, a number of both active and passive prevention measures have been implemented in the mines, at least partially. One of the most effective, applied for many years, active means used for seismic hazard reduction, is multi-faces blasting works which by assumption should result in release of ...

The present article reports numerical results of laminar natural convection heat transfer within an air filled semi cylindrical cavity with its horizontal walls submitted to different heating models. In this work, the horizontal surface is maintained at constant temperatures Tc (Dirichlet condition) or heat fluxes q (Newman condition), while that of the opposite surface is considered at cold temperature Tf. The parameters governing the problem are the Rayleigh number (103 < Ra < 106), and the Prandtl number (Pr = ...

Tsunami in the Black Sea is a relatively rare phenomenon. Because of its rare occurrence and small volume of full-scale data, tsunami hazard of the Black Sea region has not been sufficiently studied. However, the chance of tsunami waves is still on. In the XX century, four known tsunami phenomena were recorded by marigraphs. These include two events that occurred in 1927, events of 1939 and 1966. Vertical sea level fluctuations were recorded in several points on the Black Sea coast. However, true sea level heights...

Information about informal Romani settlements housing are not found in books or archives. They are found ?live?, in settlements. The intent of this paper is to point out that they represent a world of signals that can be detected through the methodological tools of observation and discussion with residents; also and therefore, to create guidelines for operational tools useful for an aware and contemporary design of Romani house. The paper starts from the fact that including cultural components in projects that are...

This work is devoted to obtaining and characterization of wood-mineral composites based on wood debarking waste and basalt screenings, which have improved ecological,strength, sound and heat insulation properties. To achieve this goal, the following tasks were solved: the regularities of the process of spontaneous filling of the porous space of the wood matrix with mineral fine particles due to the capillary forces of plant raw materials were established; simulation models of the structure and functional propertie...

The necessity of fulfilling as many conditions as possible in the specification resulted in the creation of composite materials. This idea developed in the aerospace industry was later used successfully in all industrial branches. The two materials that have been used are chemically distinct, each of which retains its properties in the composite, but provides the assembly with different properties and characteristics. Thus, for the continuous phase, the matrix was used an aluminum alloy, and for the discontinuous ...

Technology development has been enormous in recent years. This is particularly noticeable as regards telephones and personal computers as well as other devices e.g. modern GNSS receivers which currently are the basic equipment of even small land surveying firms. Drones are an example that shows the dynamics of technology development, especially in a few recent years. Currently, the aim is to capture data of the best possible quality, yet capturing it should generate the lowest possible costs. In this regard, drone...

Industry is constantly forced to look for new ways to make production processes environmentally safe and products more competitive. In this regard, microbiological enzyme preparations increasingly replace conventional chemical catalysts in a number of industrial processes. Such preparations, in addition to environmental friendliness and high activity, have a number of advantages over enzyme preparations of vegetable and animal origin. With the aim of creating new recombinant lipase, we analyzed data on the activit...

Industry is constantly forced to look for new ways to make production processes environmentally safe and products more competitive. In this regard, microbiological enzyme preparations increasingly replace conventional chemical catalysts in a number of industrial processes. Such preparations, in addition to environmental friendliness and high activity, have a number of advantages over enzyme preparations of vegetable and animal origin. With the aim of creating new recombinant lipase, we analyzed data on the activit...

The article presents risk assessment during the surveyor's work. Threats occurring during geodetic measurements in the field were determined. These are various types of measurements carried out for investment purposes, topographic and property boundaries survey, determination of displacements and deformations of structures and engineering structures, etc. It is worth, therefore, that each surveyor should be aware of the dangers that may threaten him during work. Hazards related to geodetic measurements have been i...

The use of bioenergy is gradually increasing, so are the number of different technologies to produce it. Particularly during the last years, new biogas plants had been built across Latvia to ensure more efficient use of farming and other agronomic waste or by-products. The aim of the research is to determine occupational risk factors at biogas plants in Latvia. The research summarises the risk factors of the biogas plant environment, compares the results of observations of biogas plants, performs a survey and an a...

Trichloroethene (TCE) and tetrachloroethene (PCE) have been detected in water of the Triassic carbonate aquifer in Tarnowskie G?ry area since 1994. Since 2005, TCE and PCE in groundwater have been constantly monitored by the Voivodship Inspectorate for Environmental Protection in Katowice in 12 observation wells and pumping wells located in Tarnowskie G?ry and outskirts of the city. After 24 years chlorinated solvents still pose a serious environmental risk and are responsible for closure of selected wells situate...

Russian northern territories? cultural advance and development were directly connected to the extraction of minerals. Development of northwest Russia?s mineral resources became more planned and systematic with ?Mining Prikaz? established by Peter the Great. There are numerous old mines preserved in Leningrad region and Karelia, and their cultural potential is underestimated by the state and their historical value is downgraded. This article considers spreading in Russia practices of using shut-down underground min...

The first isolation of the Paratethys from the Tethys Ocean (that included the Mediterranean region), at the beginning of the Oligocene Epoch, at around 33 My (million years) led to significant palaeobiogeographical changes in Europe. The present day Romanian territory belongs, since the Oligocene and up to the Middle Miocene, to the Central Paratethyan domain and afterwards was included in the Eastern Paratethys. The palaeogeographical isolation, produced in the Eastern Carpathians at the Eocene-Oligocene boundar...

In the work we offer an approach of the development of the web platform which could be used as prototype for software which is aimed for usage of information based on geospatial data. We consider weather information as an example of data which are connected with map information. We used Google Static Maps API and Yahoo Weather API in sample project. JSF-technology and Facelets are used for the presentation of web pages. The development of application is based on JavaBeans architecture which supports the features o...

Most of bilingual or multilingual dictionaries, especially the printed ones can be represented as a simple relational database with two relations with cardinality 1:N for each side of the dictionary. This database structure is actually sufficient if the user needs only word to word translation and if they are experienced enough to choose a proper translation from mostly many synonyms. One step forward is a contextual dictionary. The translation is influenced by the context of the word, what can make the translatio...

Polycrystalline hypoeutectoid aluminum bronze was fabricated by melting of pure metals technique in an induction furnace. Cu-Al-Ni alloy was investigated in cast state and after hot extrusion. Moreover, thermomechanical treatments was conducted via torsion tests between room temperature and 9000C. The research focused to investigate the factors influencing the deformation behaviour, mechanical properties and microstructural evolution of a Cu-Al-Ni alloy. Mechanical characterization showed that upon extrusion and t...

In the work we consider the problem of optimal organization of healthcare system taking into account both map and statistical data. Map data include degrees of urbanization which classify the character of an area. This approach is based on mapping the territory by a grid square cell of 1 km2. Data about public health include research concerning spreading of basic infectious diseases and distribution of hospital system. Decision making is based on application of decision tree induction algorithm for tuples containi...

In the work we propose the model of cellular automata for predator-prey system, which is based on the system of lattice differential equations with delay. The model is based on biological assumptions for arbitrary cell. Each cell can assume a value of state in some discrete scales, which mean density of predator or prey population that the cell contain, respectively. We have some constant birthrate for prey population. Preys are neutralized by predators with some probability rate. Prey population tends to some car...

In the work we propose the model of cellular automata for predator-prey system, which is based on the system of lattice differential equations with delay. The model is based on biological assumptions for arbitrary cell. Each cell can assume a value of state in some discrete scales, which mean density of predator or prey population that the cell contain, respectively. We have some constant birthrate for prey population. Preys are neutralized by predators with some probability rate. Prey population tends to some car...

Background: In the classical kinetics theory of a nuclear reactor, inserting the slightest reactivity-jump leads to an unlimited exponential increase in the reactor power. The purpose this study is the establishment of the nature of such a phenomenon. Methods: Theoretical research is based on the physics of the chain fission reaction as a sequence of cycles, each cycle of which is initiated by neutrons of the previous cycle. The study method consists in determining the change in the output neutron density of the c...

Although significant progress has been made in maintaining equipment in industrial systems in an effective manner, maintenance of equipment remains a challenge due to factors such as size, cost, complexity, and competition. Any undesired event may present an immediate environmental, performance, or safety implication. Thus, there is a need for effective maintenance engineering and maintenance practices that will positively influence critical success factors such as safety, product quality, price and profitability....

The public hearings are the kinds of the public control?s forms. These hearings are usually devoted to considering of environmental issues, problems of town planning, land use, i.e. the most important problems for population. Research objective is search of additional legal opportunities for citizens' activity in questions of local life. The author analysed the positive experience of participation of inhabitants in some American municipalities by solution of city problems. However there is a number of the problems...