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Gawedal A.,University of Silesia | Golonka J.,Academy of Mining and Metallurgy of Poland
Geodinamica Acta | Year: 2011

Magmatic and metamorphic events, imprinted in the crystalline rocks of the so-called core mountains inside the Alpine structure of the Inner Carpathians, allow the re-construction of the history of the Rheic Ocean opening, its development and its final closure. Intra-Carpathian core-mountains are the remnants of the continents that drifted away from Gondwana and docked, initially, with Baltica as part of Avalonia and later on as parts of the Gondwana-derived Armorica Terrane Group or as a separate micro-continent. All magmatic suites, mafic and felsic, present in the Carpathians core mountains, show similarities to those found in the European Variscan Belt. All described-and dated metamorphic and magmatic events also have equivalents in the evolution of the Caledonian-Variscan Belts of Europe. The most pronounced feature of all Carpathian core mountains is the syn-collisional, multistage I/S granitoid magmatism (370-340 Ma) related to subduction, mafic-magma influx, extensional decompression and slab melting. That episode marked the Laurussia-Gondwana collision and closure of the Rheic Ocean, as in the whole of Central and Western Europe. The Carpathian core-mountains, currently dispersed inside the Alpine mountain chain, can be considered the broken fragments of the eastern prolongation of the Variscan orogenic belts-possibly part of the Moldanubian Unit. © 2011 Lavoisier SAS.

Orlowska E.,IThemba LABS | Orlowska E.,University of Aarhus | Przybylowicz W.,IThemba LABS | Przybylowicz W.,Academy of Mining and Metallurgy of Poland | And 4 more authors.
Environmental Pollution | Year: 2011

The effect of arbuscular mycorrhizal fungi (AMF) on growth and element uptake by Ni-hyperaccumulating plant, Berkheya coddii, was studied. Plants were grown under laboratory conditions on ultramafic soil without or with the AM fungi of different origin. The AM colonization, especially with the indigenous strain, significantly enhanced plants growth and their survival. AMF affected also the elemental concentrations that were studied with Particle-induced X-ray emission (PIXE). AMF (i) increased K and Fe in shoots, Zn and Mn in roots, P and Ca both, in roots and shoots; (ii) decreased Mn in shoots, Co and Ni both, in shoots and roots. Due to higher biomass of mycorrhizal plants, total Ni content was up to 20 times higher in mycorrhizal plants compared to the non-mycorrhizal ones. The AMF enhancement of Ni uptake may therefore provide an improvement of a presently used technique of nickel phytomining. © 2011 Elsevier Ltd. All rights reserved.

Dabrowski D.,Academy of Mining and Metallurgy of Poland | Jamro E.,Academy of Mining and Metallurgy of Poland | Cioch W.,Academy of Mining and Metallurgy of Poland
Acta Physica Polonica A | Year: 2010

This paper studies the architecture of a neural classifier designed to identify technical condition of machines, based on vibroacoustic signals. The designed neural network is optimized for implementation on Field Programmable Gate Arrays (FPGA) programmable devices. FPGA allows massive parallelism and thus real-time classification as each neuron can execute arithmetic operations simultaneously. The classifier of vibroacoustic signals was designed and tested for the self - organized neural network. The teaching vectors are based on estimates derived from processed vibroacoustic signals generated by rotary machines. The created classifier was applied for recognizing technical state of demonstrative toothed gear DMA1 in variable operating conditions.

Cyganek B.,Academy of Mining and Metallurgy of Poland | Borgosz J.,Academy of Mining and Metallurgy of Poland
European Signal Processing Conference | Year: 2015

The paper presents a novel feature-based stereo method that employs a tensor detector of local structures in binary images. The main strength of the presented methods lies in its immunity to false matches as well as very small set of control parameters. Thus, it can be easily implemented on almost every computer platform and be used as a very flexible depth recovery method in navigation or 3D reconstruction. © 2002 EUSIPCO.

Kowalewski A.,Academy of Mining and Metallurgy of Poland
European Control Conference, ECC 1999 - Conference Proceedings | Year: 2015

Various optimization problems associated with the optimal control of distributed parameter systems with retarded arguments appearing in the boundary conditions have been studied recently by [wang], [know], [wong], [kow88a], [kow88b], [kow93a], [kow93b], [kow98a], [kow98b], and [kowdud]. In this paper, we consider an optimal distributed control problem for a linear hyperbolic system in which retarded argument appears in the integral form in the Neumann boundary condition. The performance functional has the quadratic form. The time horizon is fixed. Finally, we impose some constraints on the distributed control. Necessary and sufficient conditions of optimality with the quadratic performance functional and constrained control are derived for the Neumann problem. © 1999 EUCA.

Barbacki A.P.,Academy of Mining and Metallurgy of Poland
Environment Protection Engineering | Year: 2010

The paper discusses the geological and technical aspects of geothermal energy utilization in south-east Poland, such as the availability of thermal aquifers and the techniques for putting the latter into practical use. The geological and geothermal features of the region are presented within the context of existent aquifers whose geothermal resources could be used for heating and recreation. Particulary favourable hydrogeological conditions exist in the Inner Carpathians, in the Podhale Trough, where one geothermal plant and thermal pools that exploit geothermal energy can be found. Equally interesting are the areas north of the Cracow-Tarnów-Rzeszów line, where in the Tertiary, Mesozoic and Paleozoic aquifers of the Miechów Trough and the Carpathian Foredeep a water temperature ranges from 20 to 60 °C (in Poland, thermal water is defined as a water with well-head temperature of above 20 °C). The paper presents technological solutions for the recovery and management of heat in this area, together with the examples of how heat pumps and combined heat and power units are used in Poland. In order to assess the geothermal potential of a given area, we must first determine whether the extraction of geothermal heat there is economically viable. To answer this question we must consider two basic elements, i.e. the type of thermal aquifer involved and the technological solutions that can be applied to utilize the source [1], [2].

Barbacki A.,Academy of Mining and Metallurgy of Poland
Renewable and Sustainable Energy Reviews | Year: 2012

Geothermal resources in Poland are of growing importance for the production of renewable energy. The total installed geothermal capacity (including heat pumps) at the end of 2008 was ca. 281 MWt, while heat sales about 1501 TJ. Poland is characterised by low-temperature geothermal resources connected mostly with the Mesozoic sedimentary formations. In the paper the estimation of thermodynamic potential of Polish geothermal fields in comparison with selected global resources was presented. Geothermal resources were classified with reference to their specific exergy and specific exergy index (SEI). These indices define the quality of the energy content of a geothermal fluid better than conventional temperature criterions. © 2011 Elsevier Ltd. All rights reserved.

Gawlicki M.,Academy of Mining and Metallurgy of Poland | Nocun-Wczelik W.,Academy of Mining and Metallurgy of Poland | Bak L.,Alpol Gips Ltd.
Journal of Thermal Analysis and Calorimetry | Year: 2010

Calorimetry was applied to an investigation of the early hydration of Portland cement (PC)-calcium aluminate cement (CAC) pastes. The heat evolution measurements were related to the strength tests on small cylindrical samples and standard mortar bars. Different heat-evolution profiles were observed, depending on the calcium aluminate cement/Portland cement ratio. The significant modification of Portland cement heat evolution profile within a few hours after mixing with water was observed generally in pastes containing up to 25% CAC. On the other hand the CAC hydration acceleration effect was also obtained with the 10% and 20% addition of Portland cement. As one could expect the compressive and flexural strength development was more or less changed-reduced in the presence of larger amount of the second component in the mixture, presumably because of the internal cracks generated by expansive calcium sulfoaluminate formation. © 2009 Akadémiai Kiadó, Budapest, Hungary.

Kuak A.,Academy of Mining and Metallurgy of Poland | Kuak A.,Jagiellonian University | Nieckarz Z.,Jagiellonian University | Zieba S.,Jagiellonian University
Journal of Geophysical Research: Atmospheres | Year: 2010

Measurements of extremely low frequency (ELF) transients can be used to obtain model parameters and rates of the strong cloud-to-ground (CG) lightning discharges that generate them. In this study, we present an analytical description of a CG lightning discharge which takes into account both a return stroke and a continuing current. Using quasi-TEM (q-TEM) solutions for the Earth-ionosphere waveguide for distances within the near zone we show that the ELF spectrum of transients strongly depends on the percentage contribution of the continuing current to the discharge process. It is supposed that during typical observational conditions the only parameter of an ELF transient that can be measured sufficiently accurately is the impulse amplitude. In relation to the observational conditions the consequences of the calibration of ELF receivers on the measured ELF impulse amplitude are discussed, particularly the role of antialias filters. It is demonstrated that measurements of the ELF transient amplitude at a known distance to the source allows the total dipole moment of the discharge to be calculated and allows contributions of the return stroke and continuing current to this process to be estimated. Furthermore, some techniques of the signal spectral filtration that enable independent measurements of the return and continuing phase of the discharge are discussed. Copyright 2010 by the American Geophysical Union.

Kowalski T.Z.,Academy of Mining and Metallurgy of Poland
Journal of Instrumentation | Year: 2015

In pulse mode operation each detector at the output gives pulse height spectra. These pulse height spectra from proportional counters filled with tissue-equivalent gas are recalculated to microdosimetric quantity for expressing the radiation quality. Energy spectra of 90Sr, 109Cd and 137Cs sources have been measured for different in geometry proportional counters for Methane- and Propane-based tissue equivalent gas (TEG) mixtures. The mixtures pressures were varied in the range from 20 hPa to 200 hPa to have simulated tissue target diameter of the order of a few μm, from 0,3 μm to 7 μm. Differences, up to 20% in the average deposited energy due to different TEG mixtures were observed. © 2015 IOP Publishing Ltd and Sissa Medialab srl.

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