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A classifier based on a decision tree with verifying cuts
(Humboldt University, 2014) Bazan, Jan G.; Bazan-Socha, Stanisława; Buregwa-Czuma, Sylwia; Dydo, Łukasz; Rząsa, Wojciech; Skowron, Andrzej
This article introduces a new method of a decision tree construction. Such decision tree is constructed with the usage of additional cuts that are used for a veri cation of cuts in tree nodes during the classi cation of objects. The presented approach allows the use of additional knowledge contained in the attributes which could be eliminated using greedy methods. The paper includes the results of experiments that have been performed on data obtained from biomedical database and machine learning repositories. In order to evaluate the presented method, we compared its outcomes with the results of classi cation using a local discretization decision tree, well known from literature. The results of comparison of the two approaches show that making decisions is more adequate through the employment of several attributes simultaneously. Our new method allowed us to achieve better quality of classi cation then the existing method.
A Domain Knowledge as A Tool For Improving Classifiers
(IOS Press, 2013) Bazan, Jan G.; Buregwa-Czuma, Sylwia; Jankowski, Andrzej
This paper investigates the approaches to an improvement of classifiers quality through the application of a domain knowledge. The expertise may be utilizable on several levels of decision algorithms such as: feature extraction, feature selection, a definition of~temporal patterns used in an approximation of the concepts, especially of the complex spatio-temporal ones, an assignment of an object to the concept and a measurement of the objects similarity. The domain knowledge incorporation results then in the reduction of the size of searched spaces. The work constitutes an overview of classifier building methods efficiently utilizing the expertise, worked out latterly by Professor Andrzej Skowron research group. The methods using domain knowledge intended to enhance the quality of classic classifiers, to identify the behavioral patterns and for automatic planning are discussed. Finally it answers a question whether the methods satisfy the hopes vested in them and indicates the directions for future development.
Analiza rzeczywistych parametrów sygnałów elektrycznych zasilających układy napędowe pomp wodociągowych
(Wydawnictwo Sigma-Not, Przegląd Elektrotechniczny, 2011-08) Bartman, Jacek; Koziorowska, Anna; Kuryło, Kazimierz; Malska, Wieslawa
W artykule przedstawiono badania przeprowadzone w stacji uzdatniania wody, których celem była analiza przebiegów prądów i napięć zawierających wyższe harmoniczne, które powstają w wyniku pracy urządzeń nieliniowych. Pomiary były przeprowadzane w stacji transformatorów, po stronie wyższego napięcia. Na kształt napięcia miały wpływ wszystkie odbiorniki nieliniowe zainstalowane w zakładzie, zasilane przez tę stację transformatorów. Skutkami występowania wyższych harmonicznych jest zniekształcenie sinusoidy napięcia zasilającego. Obecność wyższych harmonicznych w sieci zasilającej może być przyczyną zakłóceń w pracy urządzeń elektronicznych. W artykule wyznaczono wartości współczynników THD i odniesiono je do wartości określonych stosownymi normami.
Analysis of the 1– v’’ Progression of the 3A Band System (c3Pi - a3Pi) in the 13C16O Molecule Spectrum
(2000 Academic Press (Journal of Molecular Spectroscopy), 2000-09-06) Hakalla, Rafał
The 1-0, 1-1, and 1-2 bands of the 3A system of 13CO (c3Π-a3Π) have been recorded for the first time, in the form of discharge emission spectra photographed at high resolution. Preliminary rotational analysis suggests that the v = 1 level of the c3Π state is perturbed in a fashion similar to the v = 0 level, previously observed by Dabrowski et al. (1987. I. Dabrowski, M. Vervolet, and D. C. Wang, Can. J. Phys. 65, 1171-1177). Rotational combination differences from the 1720 measured lines have been used to obtain rotational constants for the v = 0-2 levels of the a3Π state, using the Hamiltonian of Brown et al. (1979. J. M. Brown, E. A. Calbourn, J. K. G. Watson, and F. D. Wayne, J. Mol. Spectrosc. 74, 294-318). and the least squares formalism of Curl and Dane (1988. J. Mol. Spectrosc. 128, 406-412), as modified by Watson (1989. J. Mol. Spectrosc. 138, 302-308). Term values for the c3Π, v = 1 level have then been obtained from the line frequencies, and a set of effective rotational constants for the c3Π (v = 1) level of 13CO has been derived. © 2000 Academic Press.
Analysis of the A1П State on the Basis of the Douglas – Herzberg Bands System in the CH+ Ion Molecule.
(Polish Academy of Sciences, Institute of Physics (Acta Physica Polonica A), 2007-06) Hakalla, Rafał; Kępa, Rafał; Szajna, Wojciech; Zachwieja, Mirosław
This paper presents an attempt of examining the irregularities appearing in a complicated A1II state of the CH+ molecule with their reasons provided. By using the experimental data for the A1Π- X1Σ+ bands system of the 12CH+ ion radical, it was proved that the vibrational and rotational quanta of the upper state reveal the same unusual behaviour, i.e. very clear nonlinear dependence on vibrational quantum number (v′ ≥ 3) of the upper state. Therefore, upper vibrational levels (v′ ≥ 3) of the A1Π state cannot be determined by means of the equilibrium constants calculated in the previous works. Due to so far unidentified A1Π state perturbations, the reduction of the wave numbers to the rovibronic parameters was carried out by means of individual, band-by-band analysis method, using with this end in view the nonlinear least squares method introduced by Curl and Dane, and Watson. This method allowed one to make already calculated constants of the rovibronic structure of regular lower state X1Σ + of A-X system independent of possible perturbations appearing in the upper state of A1Π of this system. It also enabled one to calculate for the first time the real (perturbed) term values for the A 1Π (v′ = 0, 1, 2, and 3) state of the 12CH + ion molecule. These values suggest that rotational irregularities in the A1Π state examined are negligibly small, In order to confirm the nonexistence of rotational perturbations in the A1Π (v′ = 0, 1, 2, and 3) state, up to the observed Jmax level, appropriate graphs of functions fx(J) and gx(J) introduced by Gero and Kovács, where x = Q, PR, and PR, were drawn. Also, their course was analysed in detail.
Analysis of the c3Pi (v = 0, 1) State on the Basis of the 3A Band System in the 12C16O, 13C16O, and 14C16O Molecules
(2000 Academic Press (Journal of Molecular Spectroscopy), 2001) Hakalla, Rafał
The 1-0, 1-1, and 1-2 bands of the 3A system of 13CO (c3Π-a3Π) have been recorded for the first time, in the form of discharge emission spectra photographed at high resolution. Preliminary rotational analysis suggests that the v = 1 level of the c3Π state is perturbed in a fashion similar to the v = 0 level, previously observed by Dabrowski et al. (1987. I. Dabrowski, M. Vervolet, and D. C. Wang, Can. J. Phys. 65, 1171-1177). Rotational combination differences from the 1720 measured lines have been used to obtain rotational constants for the v = 0-2 levels of the a3Π state, using the Hamiltonian of Brown et al. (1979. J. M. Brown, E. A. Calbourn, J. K. G. Watson, and F. D. Wayne, J. Mol. Spectrosc. 74, 294-318). and the least squares formalism of Curl and Dane (1988. J. Mol. Spectrosc. 128, 406-412), as modified by Watson (1989. J. Mol. Spectrosc. 138, 302-308). Term values for the c3Π, v = 1 level have then been obtained from the line frequencies, and a set of effective rotational constants for the c3Π (v = 1) level of 13CO has been derived. © 2000 Academic Press.
Analysis of the c3 (v = 0, 1) State on the Basis of the 3A Band System in the 12C16O, 13C16O, and 14C16O Molecules.
(Academic Press (Journal of Molecular Spectroscopy), 2001) Hakalla, Rafał
Six bands of the 3A system (c 3Π-a 3Π) in the CO molecule have been photographed as an emission spectra by the Geissler tube. The conventional technique of spectroscopy has been implemented. It was the first attempt to analyze the 1-3 band in the 13C16O molecule as well as the 1-2 band in the 12C16O molecule at high resolution. The Th lines were used as a standard along with the interferometric comparator equipped with a photoelectric scanning device. The 0-2 and 0-3 bands in 12C16O and the 0-3 band in 13C16O and 14C16O were reanalyzed. The total number of lines studied within the framework of this project amounts to 3071. Due to complicated and not totally described perturbations which appeared in the upper state c 3Π(v = 0, 1), the effective rovibronic structure constants for this state were calculated (for the first time in the case of v = 1 level in the 12C16O). Global merging of the rotational constants of the a 3Π(v = 0, 1, 2, 3) and c 3Π(v = 0, 1) levels in 13C16O, as well as a 3Π(v = 2, 3) and c 3Π(v = 0, 1) in 12C16O, made it possible to obtain c 3Π vibrational differences Δv1-0 = 1742.0944 (22) cm-1 in 13C16O as well as 1775.7665 (41) cm-1 in 12C16O for the first time. The so far unknown band origins of the 0-v″ and 1-v″ progressions of the 3A system in the molecules under consideration have also been determined. The first attempt to specify the equilibrium molecular constants for the c 3Π state, along with the new values for the a 3Π state, on the basis of the obtained values of merged rovibronic constants has been undertaken. The vibrational constants of the c 3Π state in the 13C16O molecule as well as in the 12C16O molecule were thus obtained for the first time. The 1-2 band of 12C16O and Dunham's isotopic relationship were implemented for that purpose. The analysis of anomalously small values of the centrifugal distortion constant D of the c 3Π state and the global character of perturbations in the observed isotopes of the CO molecule suggest homogeneous interaction between c 3Π(v = 0, 1) and the k 3Π state. Simultaneously, the analysis of the comparatively large values of the Λ-doubling parameter q and the analysis of the shifts of the term values caused by perturbations presuppose a significant influence of a heterogeneous nature of any of the 3Σ states (most probably the j 3Σ+ state) on the c 3Π(v = 0, 1) state. The article also presents the first attempt to calculate RKR potentials, r-centroids, and Franck-Condon factors for the 3A system. © 2001 Academic Press.
Anisotropy of the Conductivity in the Asymmetric Quantum Wells
(ACTA PHYSICA POLONICA A, 2008) Majchrowski, Klaudiusz; Paśko, Wioletta
Gorbatsevich et al. and Kibis suggested that a number of interesting galvano-magnetic effects could be observed in quantum structures where the symmetry with respect to the space coordinates inversion and time- -reversal are broken simultaneously. In the paper of Kibis for example, the in¯nite triangular quantum well in an external magnetic field was considered and the anisotropy of electron momentum transfer due to interaction with phonons was predicted. The role of magnetic ¯eld was to provide the time- -invariance breaking. In this work we considered the e®ect of anisotropy of electron momentum transfer due to interaction with polarized light using more realistic model of ¯nite triangular quantum well. This anisotropy leads to the anisotropy of the real part of photoconductivity and as it follows from our calculations, the e®ect though not very great, could be measurable for the attainable values of magnetic ¯eld B ¼ 5 T and the widths of quantum well.
Antiferromagnetic ordering of itinerant systems in modified mean field theory
(2003) Górski, Grzegorz; Mizia, Jerzy; Kucab, Krzysztof
Bezinwazyjna diagnostyka uzwojeń magnesujących przy użyciu sztucznych sieci neuronowych
(Przegląd Elektrotechniczny - Sigma NOT, 2011-08) Gomółka, Zbigniew; Kwiatkowski, Bogdan; Pękala, Robert
W artykule zaproponowano ideę bezinwazyjnej metody dedykowanej wykrywaniu zwarć w uzwojeniach transformatorów. Metoda oparta jest o wykorzystanie modelu matematycznego transformatora toroidalnego oraz sztucznych sieci neuronowych. Bazując na polowo-obwodowym modelu toroidu wyodrębniono sygnały diagnostyczne w postaci odkształconych przebiegów prądu uzwojenia magnesującego, które użyto w procesie uczenia sieci neuronowych. Zamieszczone wyniki testów potwierdzają wysoką skuteczność neuronowego układu diagnostycznego.
Characteristics of TiO2, Cu2O, and TiO2/Cu2O thin films for application in PV devices
(AIP Advance, 2019) Sawicka-Chudy, Paulina; Sibiński, Maciej; Pawełek, Ryszard; Wisz, Grzegorz; Cieniek, Bogumił; Potera, Piotr; Szczepan, Patryk; Adamiak, Stanisław; Cholewa, Marian; Głowa, Łukasz
Several Cu2O and TiO2 thin films and four additional TiO2/Cu2O structures were fabricated by direct current (DC) magnetron sputtering. The process parameters were selected on the basis of earlier studies and numerical simulations. We examined the morphology of a cross-section of the PV structures, roughness and topography, and the transmission spectra of the thin films. Additionally, the properties of the samples were determined by X-ray diffraction. Next, the morphology cross-sectional and layer compositions of the solar cells was evaluated by scanning electron microscopy. Only one of the TiO2/Cu2O structures appeared smooth and homogeneous with columnar-type growth. For the as-grown films, diffraction peaks were observed and identified as brookite, rutile, CuO, and Cu2O and the average roughness of the samples was 0.5, 1.2, 5.4, and 4.0 nm, respectively. Finally, the transmission spectra of the thin films were recorded. Transmission and reflection spectra of ultraviolet-visible spectroscopy were analyzed, and the optical band gap and absorption coefficient of the oxidized layers were calculated. In the region of 400 to 1000 nm, transmittance varied from 5% to 70% in the TiO2 samples, and from 15% to 40% in the Cu2O samples, and reflectance of the TiO2 and Cu2O samples ranged from 20% to 90%. In the region of 1.5 eV to 3.5 eV, the mean absorption coefficient varied from ∼105 1/cm to ∼3 · 105 1/cm for TiO2 thin film, and from ∼2 · 105 to ∼6 · 105 1/cm for Cu2O thin film. The optical band gap values of the samples shifted slightly toward bulk anatase-3.5 eV, bulk rutile-3.1 eV, and copper(I) oxide. Finally, silver contacts were used for the electrodes. One of the fabricated TiO2/Cu2O PV structures was found to be sensitive to electromagnetic radiance during the experiment.
Classifiers for Behavioral Patterns Identification Induced from Huge Temporal Data
(Humboldt University, 2014) Bazan, Jan G.; Szpyrka, Marcin; Szczur, Adam; Dydo, Łukasz; Wojtowicz, Hubert
A new method of constructing classifiers from huge volume of temporal data is proposed in the paper. The novelty of introduced method lies in a multi-stage approach to constructing hierarchical classifiers that combines process mining, feature extraction based on temporal patterns and constructing classifiers based on a decision tree. Such an approach seems to be practical when dealing with huge volume of temporal data. As a proof of concept a system has been constructed for packet-based network traffic anomaly detection, where anomalies are represented by spatio-temporal complex concepts and called by behavioral patterns. Hierarchical classifiers constructed with the new approach turned out to be better than ”flat” classifiers based directly on captured network traffic data.
Color Centers in Ca4GdO(BO3)3 Single Crystals Irradiated by Gamma Quanta
(ACTA PHYSICA POLONICA A 124, (2013) 122-124, 2013) Potera, Piotr; Lukasiewicz, T.; Piecuch, Aleksander
Comparison of Solar Tracking System Solar Tracking System and Fixed Photovoltaic Modules in Lodz
(Journal of Solar Energy Engineering, 2018-01) Sawicka-Chudy, Paulina; Sibiński, Maciej; Cholewa, Marian; Pawełek, Ryszard
The world energy consumption has exhibited high growth over the last several decades. Alternative energy sources like photovoltaic (PV) systems generate electricity, reduce pollution air, and have little environmental impact. The commonly used fixed-tilt solar panels, however, have low efficiency and high production cost. Thus, it takes a long time to obtain a return on the investment. Solar trackers increase the efficiency of PV systems and are therefore more attractive from a financial point of view. In order to design tracking systems that will be efficient, it is necessary to analyze the results during various periods during the year and over their lifespan. Thus, we performed a comparative study between fixed-tilt panels and the tracking system installed in Lodz, Poland. Fixed-tilt panels are at normal to the Earth's surface (90 deg from horizontal plane) and are attached to a building façade, azimuth 180 deg (S direction) with 15 cm ventilation gap so slight efficiency drop may be presumed. We performed short- and long-term analyses of the solar tracking and fixed-tilt systems, which allowed us to conclude that the panels tracking the sun had an additional gain of energy during the year as compared to the fixed-tilt panels. During some months, however, the solar tracking system did not produce as much energy as the fixed-tilt, vertically positioned panels. These results might be useful in designing and constructing solar tracking PV systems.
Correlation Effects in Band Ferromagnetism
(cond-mat, 2004) Górski, Grzegorz; Mizia, Jerzy
We analyze the influence of different on-site and inter-site interactions on the Curie temperature of transition metal magnetic elements. The numerical calculations show the well known result that the on-site Coulomb repulsion helps ferromagnetism mainly at half-filling of the band, where the 3d elements are antiferromagnetic (Cr, Mn). The inter-site interactions, which in the new approximation decrease the width of the band, favor ferromagnetism at both ends of the band. At the same time they lower the ferromagnetic Curie temperature towards experimental values, removing the paradox which persisted for a long time.
Dyskretyzacja z nadzorem tablic danych przy użyciu wielordzeniowego procesora karty graficznej (GPU)Dyskretyzacja z nadzorem tablic danych przy użyciu wielordzeniowego procesora karty graficznej (GPU)
(Przegląd Elektrotechniczny, 2014) Maciura, Łukasz
Niniejszy artykuł opisuje opracowany algorytm do dyskretyzacji tablic, polegający na masowym zrównolegleniu wyliczania optymalnego ciecia, poprzez jednoczesne badanie bardzo wielu atrybutów za pomocą wielordzeniowego procesora karty graficznej (GPU) oraz procesora (CPU). Jest to możliwe dzięki zastosowaniu technologii NVIDIA CUDA. Artykuł również porównuje prędkość działania tradycyjnego i zrównoleglonego algorytmu
Efekty termomodernizacji ścian zewnętrznych i modernizacji systemu grzewczego
(Energia i Budynek, 2012) Potera, Piotr
W artykule wyprowadzono formuły półempiryczne na zmniejszenie sezonowego zapotrzebowania ciepła i obciążenia cieplnego budynków w wyniku termomodernizacji ścian zewnętrznych
Effect of pre-growth annealing of the properties on nonpurified cadmium telleuride single crystals obtained by sublimation method
(Ukr. J. Phys. 57(8), 2012, pp 844-848, 2012) Popovych, V.D.; Gnatenko, Yu.P.; Bukyvskij, P.M.; Potera, Piotr
Electrospun fiber-based micro- and nano-system for delivery of high concentrated quercetin to cancer cells
(2023-10) Hudecki, Andrzej; Rzeszutek, Iwona; Lewińska, Anna; Warski, Tymon; Baranowska-Korczyc, Anna; Wojnarowska-Nowak, Renata; Betlej, Gabriela; Deręgowska, Anna; Hudecki, Jacek; Łyko-Morawska, Dorota; Likus, Wirginia; Moskal, Aleksandra; Krzemiński, Piotr; Cieślak, Małgorzata; Kęsik-Brodacka, Małgorzata; Kolano-Burian, Aleksandra; Wnuk, Maciej
The anticancer potential of quercetin (Q), a plant-derived flavonoid, and underlining molecular mechanisms are widely documented in cellular models in vitro. However, biomedical applications of Q are limited due to its low bioavailability and hydrophilicity. In the present study, the electrospinning approach was used to obtain polylactide (PLA) and PLA and polyethylene oxide (PEO)-based micro- and nanofibers containing Q, namely PLA/Q and PLA/PEO/Q, respectively, in a form of non-woven fabrics. The structure and physico-chemical properties of Q-loaded fibers were characterized by scanning electron and atomic force microscopy (SEM and AFM), X-ray powder diffraction (XRD), differential scanning calorimetry (DSC), goniometry and FTIR and Raman spectroscopy. The anticancer action of PLA/Q and PLA/PEO/Q was revealed using two types of cancer and nine cell lines, namely osteosarcoma (MG-63, U-2 OS, SaOS-2 cells) and breast cancer (SK-BR-3, MCF-7, MDA-MB-231, MDA-MB-468, Hs 578T, and BT-20 cells). The anticancer activity of Q-loaded fibers was more pronounced than the action of free Q. PLA/Q and PLA/PEO/Q promoted cell cycle arrest, oxidative stress and apoptotic cell death that was not overcome by heat shock protein (HSP)-mediated adaptive response. PLA/Q and PLA/PEO/Q were biocompatible and safe, as judged by in vitro testing using normal fibroblasts. We postulate that PLA/Q and PLA/PEO/Q with Q releasing activity can be considered as a novel and more efficient micro- and nano-system to deliver Q and eliminate phenotypically different cancer cells.
Emission spectroscopy of AlH: the X1Σ+, A1Π and C1Σ+ states characteristics.
(Polish Academy of Sciences, Institute of Physics (Acta Physica Polonica A), 2011-09) Szajna, Wojciech; Zachwieja, Mirosław; Hakalla, Rafał; Kępa, Ryszard
The visible spectrum of AlH has been investigated at high resolution between 20000 and 21500 cm1 using a conventional spectroscopic technique. The AlH molecules were formed and excited in an aluminium hollow-cathode lamp with two anodes, filled with a mixture of Ne carried gas and a trace of NH 3. The emission from the discharge was observed with a plane grating spectrograph and recorded by a photomultiplier tube. The 0-0 and 1-1 bands of the C1Σ+-A1∏ system and 0-2 band of the A1∏-X1Σ+ were identified at 21126, 21368 and 20276 cm1, respectively. In total 121 transition wave numbers belonging to three bands were precisely measured (with accuracy of ±0.003 cm-1) and rotationally analysed. The new data were elaborated with the help of recent X1Σ+ state parameters reported by White et al. and of the C1Σ+, A1∏ states constants reported by Szajna and Zachwieja. As a result of this merged analysis the set of the molecular parameters and rotational terms values for the three lower lying states of the AlH molecule have been significantly improved.

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