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Jacyno M.,Instytucie Socjologii Uniwersytetu Warszawskiego | Korkosz-Gebska J.,Wydziale Inzynierii Produkcji Politechniki Warszawskiej | Maj M.,Instytucie Analiz im Karola Gaussa Sp. Z O.o | Milewski J.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej | And 2 more authors.
Rynek Energii | Year: 2013

In this paper there have been presented assumptions of a concept of the Corporate Social Responsibility (CSR), as well as the ways of its implementation. The elaboration is dedicated especially to companies from the energy sector. The activities of many companies in Poland, in addition to concentrate on achieving the best financial results, take also into account the environmental and ethical aspects. In spite of the fact that CSR idea is very popular among Polish companies, what has been confirmed by numerous studies and rankings on this subject, it seems that corporate social responsibility is mainly a domain of large companies. This paper presents the benefits that CSR could bring to Polish companies in the SME sector. Source


Bielecki S.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej
Rynek Energii | Year: 2012

A cluster analysis of data of power consumption in terms can inform about the characteristic points in power consumption profiles as well as a number of models of profiles. In this paper are presented the results of cluster algorithm application. By the analysis have been dealt with measurements data of reactive power consumption by single customers and clustering day-profile as well as individual term consumption have been executed. The best results of clustering have been obtained by clustering of profiles for the number of clusters between 2 and 6, more dispersed range has been observed by clustering of term consumption. In the adapted algorithm has been used Fuzzy C-Means with addition elements improving functionality. In the paper the test results of various indexes of cluster validity have been presented. The experiments have shown that Fukuyama-Sugeno index and Fuzzy Dispersion index are more useful. Source


Fuzzy numbers can be successfully used to calculate uncertainty range of considered values. Thanks to them is possible to get at once the result with a great deal of variants continually transferring from extreme pessimistic to most optimistic with the information about grade of possibility of appearance. Complicated rules of fuzzy arithmetic, sometimes enough drastic increasing hardship of calculating, are mainly reason for insignificant popularity of fuzzy numbers in practical applications. Deducting of final formulas for ranges of dispersions of considered values should influence for universalisation of fuzzy mathematics in engineer's calculations. Dealing with estimate of reactive power flow in electric lines ought to take into consideration not only consumption and/or generation of reactive power by load customers but also load losses and idle losses in proper branches of network diagram. These days in daily exploitation not always is being owned data which are needed for more precise calculating. The method for the calculating of ranges of technical reactive power losses values in electric power lines with the use of fuzzy arithmetic has been presented in this paper. The mathematical model has been formulated also relationships which are useful to fast calculate power losses dispersion have been presented. Mentioned relationships are enabled to computations of dispersions without necessity to take complete and complicated calculations on fuzzy numbers. The discussion and the analysis of elaborated fuzzy parameters have been carried out. Source


Milewski J.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej | Wolowicz M.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej | Szablowski L.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej | Badyda K.,Warsaw University of Technology
Rynek Energii | Year: 2012

The paper presents a new approach to mathematical modeling of Polymer Electrolyte Membrane Fuel Cells. The assumptions were given. The model was created in commercially available numerical software and subjected to a process of validation. The validation was based on the available experimental data obtained on the literature research. The paper contains also the main advantages and disadvantages of a new way of modeling Polymer Electrolyte Membrane Fuel Cells. Source


Szablowski L.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej | Milewski J.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej | Kuta J.,Wydziale Mechanicznym Energetyki i Lotnictwa Politechniki Warszawskiej
Rynek Energii | Year: 2013

Proposed artificial neural network model is used to predict the demand for electric power. Appropriate architecture has been developed that network in terms of number of layers and number of neurons in each layer. Inputs to the model included: daily charge in 1 hour and day of the week, which is related to the load. However, the network received the outputs of the expected demand for electric power for the next day. The network was taught to load the data from the Institute of Thermal Technology and Warsaw University of Central Canteens of the time period from 08.10.2011 to 15.10.2011 and tested on data from a range of 10/16/2011 to 10/23/2011. Source

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