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Fuels from waste for energy source diversification

Artur Gołowicz Andrzej Wojciechowski
Polityka Energetyczna - Energy Policy Journal | 2020 | vol. 23 | No 2 | 139-156
Keywords waste energy alternative fuels energy sources diversification
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Abstract

The dynamics of economic development determines the need to develop technologies for waste recycling especially the acquisition of condensed fuels for the needs of the local diversification of energy sources. In a short time, Poland will probably lack its own produced electricity. To apply the process of diversification of energy sources, by developing methods of generating energy from waste, it becomes crucial to protect the environment. The use of cogeneration technology based on fuels derived from waste, in particular concentrated oil and gas fuels, is becoming more common and provides the basis for securing the energy supply in the preferred diversification process. Plastic waste processing in the controlled depolymerization process, which is the reverse of the polymerization process for hydrocarbon recovery – uses petroleum derivatives its production. At present, the greatest interest arises in the material recovery of plastics and rubber in the process of anaerobic thermal decomposition (thermolysis/pyrolysis), which is used on an industrial scale and consists in the degradation of polymer bonds into low molecular weight. The imperative of a modern economy is to obtain energy from fuels from waste treatment, including hazardous waste, preferably in the cogeneration process. The fuel obtained from waste may be used to obtain thermal or electric energy in order to diversify energy sources. The article presents innovative Polish technologies of obtaining fuel in processes of anaerobic thermal decomposition mainly of elastomeric and polymeric waste (including hazardous ones) for direct application in power generators of various power.

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Authors and Affiliations

Artur Gołowicz
Andrzej Wojciechowski

Searching for quantum circuits preparing maximally multipartite

Przemysław Sadowski
Theoretical and Applied Informatics | 2013 | vol. 25 | No 3-4 | 139-156
Keywords quantum systems multi-qubit systems
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Abstract

In this work genetic programming is applied to the problem of generating maximum entanglement in multi-qubit systems of different structures. We provide quantum circuits that prepares multipartite entangled states in systems consisting of up to 8 qubits. We present results pertaining to the minimum size of a quantum circuit preparing a maximally entangled multi-qubit state in cases of reduced sets of quantum gates that correspond to spin chain quantum systems.

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Authors and Affiliations

Przemysław Sadowski

Ensemble of classifiers based on deep learning for medical image recognition

Fabian Gil Stanisław Osowski Bartosz Świderski Monika Słowińska
Metrology and Measurement Systems | 2023 | vol. 30 | No 1 | 139-156 | DOI: 10.24425/mms.2023.144400
Keywords breast cancer CNN deep learning ensemble of classifiers feature selection melanoma
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Abstract

The paper presents special forms of an ensemble of classifiers for analysis of medical images based on application of deep learning. The study analyzes different structures of convolutional neural networks applied in the recognition of two types of medical images: dermoscopic images for melanoma and mammograms for breast cancer. Two approaches to ensemble creation are proposed. In the first approach, the images are processed by a convolutional neural network and the flattened vector of image descriptors is subjected to feature selection by applying different selection methods. As a result, different sets of a limited number of diagnostic features are generated. In the next stage, these sets of features represent input attributes for the classical classifiers: support vector machine, a random forest of decision trees, and softmax. By combining different selection methods with these classifiers an ensemble classification system is created and integrated by majority voting. In the second approach, different structures of convolutional neural networks are directly applied as the members of the ensemble. The efficiency of the proposed classification systems is investigated and compared to medical data representing dermoscopic images of melanoma and breast cancer mammogram images. Thanks to fusion of the results of many classifiers forming an ensemble, accuracy and all other quality measures have been significantly increased for both types of medical images.
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Authors and Affiliations

Fabian Gil
1
Stanisław Osowski
1 2
Bartosz Świderski
3
Monika Słowińska
4
  1. Military University of Technology, Faculty of Electronics, Institute of Electronic Systems, ul. gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland
  2. Warsaw University of Technology, Faculty of Electrical Engineering, pl. Politechniki 1, 00-661 Warsaw, Poland
  3. University of Life Sciences, ul. Nowoursynowska 166, 02-787 Warsaw
  4. Central Clinical Hospital Ministry of Defense, Military Institute of Medicine – National Research Institute, ul. Szaserów 128, 04-141 Warsaw, Poland

Agitation efficiency of different physical systems

Joanna Karcz Jolanta Szoplik Marta Major-Godlewska Magdalena Cudak Anna Kiełbus-Rapała
Chemical and Process Engineering | 2021 | vol. 42 | No 2 | 139-156 | DOI: 10.24425/cpe.2021.138921
Keywords agitated vessel power consumption mixing time heat and mass transfers gas hold-up
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Abstract

Efficiency of agitation was considered for different physical systems on the basis of our own experimental studies on homogenisation, heat and mass transfer as well as gas hold-up. Measurements were performed for different physical systems: Newtonian liquids of low and higher viscosity, pseudoplastic liquid, gas–liquid and gas–solid–liquid systems agitated in vessels of the working volume from 0.02 m3 to 0.2 m3. Agitated vessels of different design were equipped with a high-speed impeller (10 impellers were tested). Comparative analysis of the experimental results proved that energy inputs (power consumption) should be taken into account as a very important factor when agitation efficiency is evaluated in order to select a proper type of equipment. When this factor is neglected in the analysis, intensification of the process can be estimated only.
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Authors and Affiliations

Joanna Karcz
1
Jolanta Szoplik
1
ORCID: ORCID
Marta Major-Godlewska
1
Magdalena Cudak
1
Anna Kiełbus-Rapała
1
  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, al. Piastów 42, 71-065 Szczecin, Poland

Energy policy of the EU in Central Asia

Zhansaule Zharmakhanova Saniya Nurdavletova Ainur Issayeva Gulsum Kenzhalina Altynay Zhurasova
Polityka Energetyczna - Energy Policy Journal | 2024 | vol. 27 | No 1 | 139-156
Keywords security system strategy infrastructure pipeline investment
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Abstract

Sufficient national fossil resources and an independent water supply system are indispensable elements of the security structure of any state. Energy independence, as a factor in determining self -sufficiency, is now a basic requirement for countries or regions wishing to develop independently and freely. The purpose of this research is to identify the specifics of the European energy strategy in the Central Asian region by considering the basic areas of cooperation between the parties in this sector of the economy. This research paper has been prepared primarily using the following methods: historical, statistical, prognostic, synthesis, comparison and system analysis methods. The research delves into the intricate dynamics of foreign policy activities of European Union members concerning energy resources, particularly in a historical context. Analyzing the collaboration between Brussels and Central Asian nations, both positive and adverse facets of this alliance in the energy domain have been pinpointed. Special attention is paid to the relationship between the European Union and the Republic of Kazakhstan, emphasizing its role within the broader security framework of the region and the continent. The study offers practical recommendations for enhancing state energy strategies and fostering productive bilateral and multilateral energy partnerships.
The results and conclusions of the presented work can be used as a foundation for the development of practical recommendations to establish and improve the energy strategies of the states, and for planning bilateral and multilateral mutually beneficial cooperation in the energy sector.
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Authors and Affiliations

Zhansaule Zharmakhanova
1
ORCID: ORCID
Saniya Nurdavletova
1
ORCID: ORCID
Ainur Issayeva
1
ORCID: ORCID
Gulsum Kenzhalina
1
ORCID: ORCID
Altynay Zhurasova
2
ORCID: ORCID
  1. Gumilyov Eurasian National University, Kazakhstan
  2. Makhambet Utemisov West Kazakhstan University, Kazakhstan

The female nude and the polish sexual revolution under Gierek: a short history of a certain exhibition

Anna Dobrowolska
Kultura i Społeczeństwo | 2021 | No 4 | 139-156
Keywords nudity sexuality sexual revolution communism gender historical sociology
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Abstract

The paper aims to critically analyse media discourse on the “Venus” female nude exhibitions, organized annually in Kraków between 1970 and 1991. By analysing discourse that legitimised nudity in the public sphere, the paper sheds light on ways in which attitudes toward sexuality and the body changed during the so-called Gierek decade. The source base consists primarily of press publications, newsreels, and photo books from the 1970s. As the paper demonstrates, there were three dominant frameworks of discussing nudity in state-socialist Poland: artistic, pornographic and educational. Moreover, historical discourse analysis allows us to observe the role female nudes played in setting the stage for the Polish sexual revolution in the second half of the 1980s.
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Authors and Affiliations

Anna Dobrowolska
1
ORCID: ORCID
  1. European University Institute, Florencja

Impact of complementarity and heterogeneity on health related utility of life

Michał Jakubczyk
Central European Journal of Economic Modelling and Econometrics | 2009 | No 2 | 139-156 | DOI: 10.24425/cejeme.2009.122228
Keywords health related quality of life QALY EQ-5D complementarity heterogeneity
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Abstract

This study aims at identifying determinants of health related quality of life in Poland, and in particular at verifying whether health domains are complements or substitutes and what the impact of heterogeneity of population on the health state valuation is. The paper uses data in panel structure coming from a survey conducted in Poland and consisting of 6700 valuations (after data cleaning) of EQ-5D health states with time trade-off method. Several econometric models are built in order to detect the impact of complementarity and heterogeneity. Random effects models as well as random parameters models estimated using Bayesian approach are used. The results show that health domains are complementary goods. Especially the lack of pain/discomfort is a complement to other health domains. Demographic factors influence how health state change impacts utility. These factors encompass sex, education, respondent’s health state and even belief in life after death.

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Authors and Affiliations

Michał Jakubczyk

Convective heat transfer for fluids passing through aluminum foams

Roman Dyga Leon Troniewski
Archives of Thermodynamics | 2015 | No 1 March | 139-156 | DOI: 10.1515/aoter-2015-0010
Keywords aluminum foam geometric structure of foam convective heat transfer
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Abstract

This paper analyses the experimental findings within heat transfer when heating up air, water and oil streams which are passed through a duct with internal structural packing elements in the form of metal foams. Three types of aluminum foams with different cell sizes, porosity specifications and thermal conductivities were used in the study. The test data were collected and they made it possible to establish the effect of the foam geometry, properties of fluids and flow hydrodynamic conditions on the convective heat transfer process from the heating surface to the fluid flowing by (wetting) that surface. The foam was found to be involved in heat transfer to a limited extent only. Heat is predominantly transferred directly from the duct wall to a fluid, and intensity of convective heat transfer is controlled by the wall effects. The influence of foam structural parameters, like cell size and/or porosity, becomes more clearly apparent under laminar flow conditions.
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Authors and Affiliations

Roman Dyga
Leon Troniewski

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