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Number of results: 25
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Abstract

Energia elektryczna jest produktem przeznaczonym na sprzedaż. Ma jednak specyficzne znaczenie, które skutkuje nadaniem jej przymiotu dobra publicznego. Przyczyną takiego stanu jest konieczność zagwarantowania ciągłości jej dostaw. Niezbędna jest nie tylko dla prawidłowego funkcjonowania gospodarstw domowych, lecz w szczególności konieczna dla zapewnienia bezpieczeństwa kraju. W obowiązującym systemie gospodarczym, posługując się terminem konstytucyjnym: społeczną gospodarką rynkową, to konkurencja, uważana jest za najlepszą metodę kształtowania rynku i występujących w jego ramach stosunków. Niewątpliwie nie we wszystkich podsektorach energetyki niewidzialna ręka rynku pozwala na realizację swoich celów i funkcji w sposób wystarczający. Zatem niezbędne staje się wprowadzenie odpowiednich, aktywnych mechanizmów regulacji stanowiących skuteczny substytut dla konkurencji. Regulatorowi – czyli prezesowi Urzędu Regulacji Energetyki przypisano szereg zadań i kompetencji. Ma on obowiązek dbania o interes państwa w zakresie rozwoju przedsiębiorstw energetycznych. Równocześnie wykonuje on zadanie ochrony odbiorcy końcowego przed nakładaniem nieuzasadnionych opłat za dostarczaną energię. Jednakże regulator nie może być rzecznikiem wyselekcjonowanej grupy uczestników rynku. Jego funkcją jest zastępowanie mechanizmów konkurencji rynkowej przy wykorzystaniu dostępnych narzędzi prawnych i ekonomicznych. Rolę regulatora należy określić, jako zamiennika rynku konkurencyjnego. Połączenie wskazanych powyżej zadań jest trudne, ale możliwe, przy zachowaniu niezależności regulatora oraz nadaniu i zagwarantowaniu mu uprawnień umożliwiających, m.in. kontrolę nad gospodarką finansową spółek jednoosobowych Skarbu Państwa lub podmiotów państwowych działających w branży dystrybucji energetycznej. Niniejszy tekst ma na celu przedstawienie zależności między rozmaitymi formami aktywności organów regulacyjnych a podmiotami uczestniczącymi w rynku energii, w szczególności spółek zajmujących się dystrybucją energii elektrycznej. Autorzy wskazują, czym jest sama regulacja oraz kto wprowadza normy wiążące strony. Ponadto podejmują staranie przedstawienia czytelnikowi w przystępny sposób zagadnienia przychodu regulowanego oraz uwypuklenia w nim roli regulacji jakościowej. Istotą artykułu jest wykazanie formy i stopnia oddziaływania Regulatora na wyniki finansowe OSD.
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Authors and Affiliations

Michał Andrzej Przybył
Rafał Śpiewak
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Abstract

Embryogenic cultures of plants are exposed to various stress factors both in vitro and during cryostorage. In order to safely include the plant material obtained by somatic embryogenesis in combination with cryopreservation for breeding programs, it is necessary to monitor its genetic stability. The aim of the present study was the assessment of somaclonal variation in plant material obtained from embryogenic cultures of Picea abies (L.) Karst. and P. omorika (Pancic) Purk. maintained in vitro or stored in liquid nitrogen by the pregrowth-dehydration method. The analysis of genetic confoimity with using microsatellite markers was performed on cotyledonary somatic embryos (CSE), germinating somatic embryos (GSE) and somatic seedlings (SS), obtained from tissues maintained in vitro or from recovered embryogenic tissues (ETc) and CSE obtained after cryopreservation. The analysis revealed changes in the DNA of somatic embryogenesis-derived plant material of both Picea spp. They were found in plant material from 8 out of 10 tested embryogenic lines of P abies and in 10 out of 19 embryogenic lines of P. omorika after in vitro culture. Changes were also detected in plant material obtained after cryopreservation. Somaclonal variation was observed in ETc and CSE of P omorika and at ETv stage of P abies. However, most of the changes were induced at the stage of somatic embryogenesis initiation. These results confirm the need for monitoring the genetic stability of plants obtained by somatic embryogenesis and after cryopreservation for both spruce species.

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Authors and Affiliations

T. Hazubska-Przybył
M Dering
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Abstract

The theoretical analysis of the charge exchange process in a spark ignition engine has been presented. This process has significant impact on the effectiveness of engine operation because it is related to the necessity of overcoming the flow resistance, followed by the necessity of doing a work, so-called the charge exchange work. The flow resistance caused by the throttling valve is especially high during the part load operation. The open Atkinson-Miller cycle has been assumed as a model of processes taking place in the engine. Using fully variable inlet valve timing the A-M cycle can be realized according to two systems: system with late inlet valve closing and system with early inlet valve closing. The systems have been analysed individually and comparatively with the open Seiliger-Sabathe cycle which is a theoretical cycle for the classical throttle governing of the engine load. Benefits resulting from application of the systems with independent inlet valve control have been assessed on the basis of the selected parameters: fuel dose, cycle work, charge exchange work and a cycle efficiency. The use of the analysed systems to governing of the SI engine load will enable to eliminate a throttling valve from the system inlet and reduce the charge exchange work, especially within the range of part load operation.
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Authors and Affiliations

Zbigniew Żmudka
Stefan Postrzednik
Grzegorz Przybyła
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Abstract

The aim of this work was to investigate the effect of partial substitution of Mn by Nb on structure and thermomagnetic properties in the (Mn, Nb)-Co-Ge alloy. The master alloys were prepared by arc-melting in an arc furnace with high purity of constituent elements under a low pressure of Ar. The prepared specimens were studied in as-cast state. The X-ray was performed by BRUKER D8 Advance diffractrometer with Cu Kα radiation. The analysis of the XRD pattern revealed coexistence of two orthorhombic phases with different lattice constants. The analysis of the temperature dependence of magnetizaton confirmed the XRD results and showed that produced material manifested two magnetic phase transitions corresponding to detected phases. The values of the Curie temperature were 275 and 325 K. The values of magnetic entropy change ∆SM equaled 3.30 and 2.13 J/(kg K), respectively for recognized phases. Biphase structure of produced material allowed to reach relatively high refigeration capacity 307 J/(kg). Moreover, the analysis of field dependences of magnetic entropy change (∆SM = CBn) allowed to construct temperature dependence of exponent n. The analysis of elaborated n vs. T curve confirmed biphasic structure of produced material.
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Authors and Affiliations

K. Kutynia
1
ORCID: ORCID
P. Gębara
1
ORCID: ORCID
A. Przybył
1
ORCID: ORCID

  1. Czestochowa University of Technology, Institute of Physics, 19 Armii Krajowej Av., 42-200, Częstochowa, Poland
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Abstract

Videoplethysmography is currently recognized as a promising noninvasive heart rate measurement method advantageous for ubiquitous monitoring of humans in natural living conditions. Although the method is considered for application in several areas including telemedicine, sports and assisted living, its dependence on lighting conditions and camera performance is still not investigated enough. In this paper we report on research of various image acquisition aspects including the lighting spectrum, frame rate and compression. In the experimental part, we recorded five video sequences in various lighting conditions (fluorescent artificial light, dim daylight, infrared light, incandescent light bulb) using a programmable frame rate camera and a pulse oximeter as the reference. For a video sequence-based heart rate measurement we implemented a pulse detection algorithm based on the power spectral density, estimated using Welch’s technique. The results showed that lighting conditions and selected video camera settings including compression and the sampling frequency influence the heart rate detection accuracy. The average heart rate error also varies from 0.35 beats per minute (bpm) for fluorescent light to 6.6 bpm for dim daylight.

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Authors and Affiliations

Jaromir Przybyło
Eliasz Kańtoch
Mirosław Jabłoński
Piotr Augustyniak
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Abstract

The aim of the study was to present an experimental investigation of the influence of the RMF on mixing time. The obtained results suggest that the homogenization time for the tested experimental set-up depending on the frequency of the RMF can be worked out by means of the relationship between the dimensionless mixing time number and the Reynolds number. It was shown that the magnetic field can be applied successfully to mixing liquids.

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Authors and Affiliations

Alicja Przybył
Rafał Rakoczy
Maciej Konopacki
Marian Kordas
Radosław Drozd
Karol Fijałkowski
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Abstract

Electricity storage is one of the best-known methods of balancing the energy supply and demand at a given moment. The article presents an innovative solution for the construction of an electric energy storage device obtained from an innovative photovoltaic panel made of new dye-based photovoltaic modules and newly developed supercapacitors – which can be used as an emergency power source. In the paper, for the first time, we focused on the successful paring of new dye-sensitized solar cell (DSSC) with novel supercapacitors. In the first step, a microprocessor stand was constructed using Artificial Intelligence algorithms to control the parameters of the environment, as well as the solar charger composed of six DSSC cells with the dimensions of 100_100 mm and 126 CR2032 coin cells with a total capacitance of 60 F containing redox-active aqueous electrolyte. It was proven that the solar charger store enough energy to power, i.e. SOS transmitter or igniters, using a 5 V signal.
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Authors and Affiliations

Ireneusz Plebankiewicz
1
ORCID: ORCID
Krzysztof. A. Bogdanowicz
1
ORCID: ORCID
Paweł Kwaśnicki
2 3
Magdalena Skunik-Nuckowska
4
Patryk M. Rączka
3
Paweł Kulesza
4
Agnieszka Iwan
1
ORCID: ORCID
Wojciech Przybył
1

  1. Military Institute of Engineer Technology, ul. Obornicka 136, 50-961 Wrocław, Poland
  2. Research & Development Centre for Photovoltaics, ML System S.A. Zaczernie 190G, 36-062 Zaczernie, Poland
  3. Department of Physical Chemistry and Physicochemical Basis of Environmental Engineering, Institute of Environmental Engineering in Stalowa Wola, John Paul II Catholic University of Lublin, ul. Ofiar Katynia 6, 37-450 Stalowa Wola Poland
  4. Faculty of Chemistry, Warsaw University, ul. Pasteura 1, 02-093 Warsaw, Poland

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