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Abstract

The biofiltration process in the biologically activated carbon filters (BAC) is one of advanced methods of water treatment. It enables efficient elimination of dissolved organic matter and some inorganic pollutants. The production of high-quality drinking water requires an appropriate method of filter work control based on biofilm growth assessment. The first aim of the study was to assess the microbial development in beds of two BAC filters with the use of various methods. The second aim was to compare the obtained results and indicate the method which could support filter operators during routine control of biofiltration process. The study was carried out in a pilot scale on models of BAC filters during two filter runs. The analysis of Microorganisms was performed in water samples collected from different depths of the filter beds with the use of culture method (HPC), metabolica ctivity assay (with the FDA), epifluorescence microscopy – total cell count method (TCC) and biochemical method (system Vitek 2 Compact). No statistical correlation between HPC and metabolic activity assay was noted. Total bacteria number determined with the use of TCC was approx. 100–900 times higher than in the HPC method. The biochemical tests revealed the presence of several Gram-negative species. The comparison of the applied methods shows that microbial activity assay is the most useful, fast and low-cost method which may be applied additionally to the HPC method at standard water treatment plant laboratory.
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Authors and Affiliations

Dorota Holc
1
ORCID: ORCID
Beata Mądrecka-Witkowska
1
ORCID: ORCID
Małgorzata Komorowska-Kaufman
1
ORCID: ORCID
Elżbieta Szeląg-Wasielewska
2
Alina Pruss
1
ORCID: ORCID
Zefiryn Cybulski
3

  1. Poznan University of Technology, Institute of Environmental Engineering and Building Installations, Poland
  2. Adam Mickiewicz University in Poznań, Faculty of Biology, Department of Water Protection, Poland
  3. Greater Poland Cancer Center, Microbiology Laboratory, Poland
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Abstract

Postrzeganie czasu jest dla funkcjonowania ludzkiego umysłu kluczowe. Jego zaburzenie powoduje trudności np. w komunikacji językowej. Prowadzone przez nas badania pokazują, jak można naprawić zepsuty .zegar neuronalny" u osób z trudnościami w porozumiewaniu się.
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Authors and Affiliations

Elzbieta Szeląg
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Abstract

The article presents a method of designing single-chamber rectangular detention reservoirs based on nomographs connecting the parameters and the shape of the inflow with the reservoir hydrograph (triangular, described by the power function and described by the gamma distribution) as well as the hydraulic characteristics of the accumulation chamber and the orifice. The preparation of nomographs involved using the SWMM (Storm Water Management Model) program with the application of numerical calculations’ results of a differential equation for the stormwater volume balance. The performed analyses confirm a high level of similarity between the results of calculating the reservoir volume obtained by using the above mentioned program and using the developed nomographs. The examples of calculations presented in the paper confirm the application aspects of the discussed method of designing the detention reservoir. Moreover, based on the conducted analyses it was concluded that the inflow hydrograph described by the gamma distribution has the greatest impact on the reservoir’s storage volume, whereas the hydrograph whose shape in the rise and recession phases is described by the power function has the smallest effect.

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Authors and Affiliations

Bartosz Szeląg
Maciej Mrowiec
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Abstract

Abstract Chromosome numbers for 16 Hieracium s.str. species from Bosnia and Herzegovina, Bulgaria, Macedonia, Montenegro, Poland, Romania and Serbia are given and their metaphase plates are illustrated. Chromosome numbers are published for the first time for H. filarszkyi Jáv. & Zahn 2n = 3x = 27, H. fritschianum Hayek & Zahn 2n = 3x = 27, H. fritzeiforme Zahn 2n = 3x = 27, H. hercegovinicum (Freyn & Vandas) Szeląg 2n=3x=27, H. nivimontis (Oborny & Zahn) Chrtek fil. 2n = 4x = 36, H. vagneri Pax 2n = 4x = 36, as well as three undescribed species of hybrid origin between H. olympicum Boiss. and H. sparsum Friv. 2n = 4x = 36, H. naegelianum Panc. and H. scardicum Bornm. & Zahn 2n = 3x = 27, and H. transylvanicum Heuff. and H. umbellatum L. 2n = 4x = 36.
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Authors and Affiliations

Krystyna Musiał
Zbigniew Szeląg
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Abstract

The authors report the first discovery of diploid populations of Hieracium naegelianum Panč. subsp. naegelianum and H. naegelianum subsp. ljubotenicum Behr & Zahn., and give the first chromosome counts for H. cernuum Friv., H. gymnocephalum Griseb. ex Pant., H. sparsum Friv., Pilosella pavichii (Heuff.) Holub and P. serbica (F. W. Schultz & Schultz-Bip.) Szeląg from Macedonia and/or Montenegro. A diploid chromosome count for Hieracium renatae Szeląg is confirmed based on material from the whole distribution range of the species. An emasculation experiment showed that all the analyzed diploid Hieracium taxa reproduce sexually.

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Authors and Affiliations

Zbigniew Szeląg
Tomasz Ilnicki
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Abstract

Chromosome numbers of 46 Hieracium L. and Pilosella Vaill. taxa from Austria, Bulgaria, Czech Republic, Macedonia, Montenegro, Poland, Romania, Serbia and Slovakia are presented. Chromosomes numbers are given for the first time for Hieracium amphigenum Briq. 2n = 3× = 27, H. bohatschianum Zahn 2n = 4× = 36, H. borbasii R. Uechtr. 2n = 4× = 36, H. cernuum Friv. 2n = 2× = 18, H. hazslinszkyi Pax 2n = 3× = 27, H. mirekii Szeląg 2n = 4× = 36, H. polyphyllobasis (Nyár. & Zahn) Szeląg 2n = 3× = 27, H. porphyriticum A. Kern. 2n = 4× = 36, H. racemosum Waldst. & Kit. ex Willd. subsp. racemosum 2n = 3× = 27, H. scardicum Borm. & Zahn 2n = 4× = 36, H. sparsum subsp. ipekanum Rech. fil. & Zahn 2n = 4× = 36, H. sparsum subsp. peristeriense Behr & Zahn, H. sparsum subsp. squarrosobracchiatum Behr & al. 2n = 3× = 27, H. tomosense Simk. 2n = 4× = 36, H. tubulare Nyár. 2n = 4× = 36, H. werneri Szeląg 2n = 3× = 27 and Pilosella fusca subsp. subpedunculata (Zahn) Szeląg, as well as five species of Hieracium sect. Cernua R. Uechtr. not described to date and a hybrid between H. bifidum s. lat. and H. pojoritense Woł

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Authors and Affiliations

Tomasz Ilnicki
Zbigniew Szeląg
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Abstract

Time perception is a key function of the human mind. Its disruption can lead to difficulties in many areas of our cognition, including language communication. Our research has managed to repair damaged "neural clocks" in people who have difficulties in language communication.
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Authors and Affiliations

Elżbieta Szeląg
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Abstract

The paper formulates some objections to the methods of evaluation of uncertainty in noise measurement which are presented in two standards: ISO 9612 (2009) and DIN 45641 (1990). In particular, it focuses on approximation of an equivalent sound level by a function which depends on the arithmetic average of sound levels. Depending on the nature of a random sample the exact value of the equivalent sound level may be significantly different from an approximate one, which might lead to erroneous estimation of the uncertainty of noise indicators. The article presents an analysis of this problem and the adequacy of the solution depending on the type of a random sample.
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Authors and Affiliations

Bartosz Przysucha
Wojciech Batko
Agata Szeląg
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Abstract

Reflecting structures placed over the stage in auditoria and concert halls should provide sound reflection in a way that enhances sound emission from the stage without causing acoustic defects in the interior. Model studies conducted by the authors were used to determine the relative level of sound reflection by reflecting structures as a function of frequency for a number of geometric configurations and materials. Analysis of the results allowed drawing conclusions about the effect of modifications of the ceiling over the reflecting panels on the quality of the sound reflected from them. It was shown that modification of the ceiling over the reflecting panels by employing highly sound absorbing materials significantly improved the characteristics of the reflected sound. Also, certain configurations of elements located in the space under the ceiling should be avoided, as the experiments indicated the occurrence of adverse acoustic effects.

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Authors and Affiliations

Tadeusz Kamisiński
Agata Szeląg
Jarosław Rubacha
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Abstract

Abstract Chromosome numbers for 13 species of Hieracium L. s.str. from Bulgaria, Macedonia, Poland and Romania are given and their metaphase plates are illustrated. Chromosome numbers are published for the first time for H. djimilense s.lat. 2n=3x=27, H. fiekii R. Uechtr. 2n=3x=27, H. glabrescens (F. W. Schultz) Murr 2n=3x=27, H. juranomorphum Zahn 2n=3x=27, H. sparsiflorum subsp. sparsiceps Zahn 2n=3x=27 and H. sparsum subsp. naegelianiforme Behr & Zahn 2n=3x=27.
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Authors and Affiliations

Agnieszka Janas
Zbigniew Szeląg
Krystyna Musiał
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Abstract

Abstract Chromosome numbers for 12 Hieracium s.str. species from Bulgaria, Macedonia, Montenegro, Poland, Romania and Serbia are given and their metaphase plates are illustrated. Chromosome numbers are published for the first time for H. albinum Fries 2n=4x=36, H. bukovicae Rohlena & Zahn; 2n=3x=27, H. retyezatense subsp. subatratiforme Neičeff & Zahn 2n=4x=36, H. velenovskyi Freyn 2n=3x=27, as well as two undescribed species belonging to the H. bohatschianum agg. 2n=4x=36 and H. nigrescens agg. 2n=4x=36 and a hybrid between H. naegelianum Pančić and H. bifidum s.lat. 2n=4x=36.
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Authors and Affiliations

Agnieszka Janas
Zbigniew Szeląg
Krystyna Musiał
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Abstract

Chromosome numbers for 15 taxa of Hieracium L. s.str. from Bulgaria, Greece, Macedonia, Poland, Romania

and Slovakia are given and their metaphase plates are illustrated. Chromosome numbers are published for the

first time for H. vagneri Pax s.str. (2n = 4x = 36), H. wiesbaurianum subsp. herculanum Zahn (2n = 4x = 36),

H. wiesbaurianum subsp. kelainephes Nyár. & Zahn (2n = 3x = 27), as well as for two undescribed species

of hybrid origin between H. umbellatum L. and H. wiesbaurianum s.lat. (2n = 3x = 27), and between H. sparsum

Friv. and H. schmidtii s.lat. (2n = 3x = 27), and for three undescribed species of the H. djimilense agg.

(2n = 3x = 27), H. heldreichii agg. (2n = 3x = 27), and H. sparsum agg. (2n = 3x = 27). Furthermore, the chromosome

numbers of two undescribed species of hybrid origin between H. umbellatum L. and H. wiesbaurianum

s.lat. (2n = 3x = 27), and between H. sparsum Friv. and H. schmidtii s.lat. (2n = 3x = 27) are given. A new,

tetraploid chromosome number is given for H. barbatum Tausch from the northernmost locality of the species

in Europe.

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Authors and Affiliations

Krystyna Musiał
Agnieszka Janas
Zbigniew Szeląg
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Abstract

In water systems, both biologically and chemically synthesized molecules may reduce environmental quality and influence essential ecosystems structure and function. These substances include aldehydes from various sources, also those relates to the activities of primary producers. The focus of the study was vertical distribution of several aliphatic aldehydes and phytoplankton biomass in an urban lake in Poznań (Wielkopolska Lakeland, Poland) under human pressure. Water samples were collected from surface lake to bottom, every 2 m. Plankton was analyzed under inverted and epifluorescence microscopes. The biomass was estimated from microscopic measurements and cell volume of each species. Thirteen aldehydes and acetone were analyzed using gas chromatography with an electron capture detector after derivatization and extraction processes. Aldehydes concentrations varied between 32.7 and 346.2 μg L-1. Formaldehyde, acetaldehyde and propanal were characterized by the highest concentration both at low and high phytoplankton biomass. Phytoplankton biomass included prokaryotic and eukaryotic cells, and ranged between 0.25 and 2.94 mg L-1. Cryptophytes and diatoms were often the most important components of phytoplankton communities, although in some cases the haptophytes and dinophytes comprised a much higher proportion. Total aldehyde concentration was significantly correlated with total phytoplankton biomass (r=0.705, p <0.05), and even higher correlation was observed between acetone and phytoplankton biomass (r=0.917). This indicates phytoplankton as an important source of carbonyl compounds in surface waters. Thus, the knowledge of different aspects of their origin and distribution in the lake is important both in ecological research and in water management.

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Authors and Affiliations

Elżbieta Szeląg-Wasielewska
1
Agata Dąbrowska
2

  1. Faculty of Biology, Adam Mickiewicz University in Poznań, Poland
  2. Faculty of Chemistry, Adam Mickiewicz University in Poznań, Poland
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Abstract

The paper presents the verification of a solution to the narrow sound frequency range problem of flat reflective panels. The analytical, numerical and experimental studies concerned flat panels, panels with curved edges and also semicircular elements. There were compared the characteristics of sound reflected from the studied elements in order to verify which panel will provide effective sound reflection and also scattering in the required band of higher frequencies, i.e. above the upper limit frequency. Based on the conducted analyzes, it was found that among some presented solutions to narrow sound frequency range problem, the array composed of panels with curved edges is the most preferred one. Nevertheless, its reflection characteristic does not meet all of the requirements, therefore, it is necessary to search for another solution of canopy which is effective over a wide frequency range.
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Authors and Affiliations

Agata Szeląg
Tadeusz Kamisiński
Mirosława Lewińska
Jarosław Rubacha
Adam Pilch
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Abstract

The aim of the study was to evaluate the possibility of applying different methods of data mining to model the inflow of sewage into the municipal sewage treatment plant. Prediction models were elaborated using methods of support vector machines (SVM), random forests (RF), k-nearest neighbour (k-NN) and of Kernel regression (K). Data consisted of the time series of daily rainfalls, water level measurements in the clarified sewage recipient and the wastewater inflow into the Rzeszow city plant. Results indicate that the best models with one input delayed by 1 day were obtained using the k-NN method while the worst with the K method. For the models with two input variables and one explanatory one the smallest errors were obtained if model inputs were sewage inflow and rainfall data delayed by 1 day and the best fit is provided using RF method while the worst with the K method. In the case of models with three inputs and two explanatory variables, the best results were reported for the SVM and the worst for the K method. In the most of the modelling runs the smallest prediction errors are obtained using the SVM method and the biggest ones with the K method. In the case of the simplest model with one input delayed by 1 day the best results are provided using k-NN method and by the models with two inputs in two modelling runs the RF method appeared as the best.

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Authors and Affiliations

Bartosz Szeląg
Lidia Bartkiewicz
Jan Studziński
Krzysztof Barbusiński
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Abstract

In the paper, the mathematical model of coupled electromagnetic and thermal phenomena in the pulse transformer taking into account the magnetic hysteresis is presented. For the mapping of magnetic hysteresis, Jiles-Atherton model is applied. In order to solve field equations, the finite element method (FEM), "step-by-step" procedure and Newton-Raphson algorithm are used. Software elaborated on this basis is used for analysis of hysteresis loss in the core. Selected results of investigations are shown.
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Authors and Affiliations

Wiesław Łyskawiński
Piotr Sujka
Wojciech Szeląg
Mariusz Barański
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Abstract

In recent years, a significant development of technologies related to the control and communication of mobile robots, including Unmanned Aerial Vehicles, has been noticeable. Developing these technologies requires having the necessary hardware and software to enable prototyping and simulation of control algorithms in laboratory conditions. The article presents the Laboratory of Intelligent Mobile Robots equipped with the latest solutions. The laboratory equipment consists of four quadcopter drones (QDrone) and two wheeled robots (QBot), equipped with rich sensor sets, a ground control station with Matlab-Simulink software, OptiTRACK object tracking system, and the necessary infrastructure for communication and security. The paper presents the results of measurements from sensors of robots monitoring various quantities during work. The measurements concerned, among others, the quantities of robots registered by IMU sensors of the tested robots (i.e., accelerometers, magnetometers, gyroscopes and others).

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Authors and Affiliations

Sebastian Dudzik
Piotr Szeląg
Janusz Baran

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