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Gdańsk University of Technology

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  • Analiza porównawcza sposobów wyznaczania obciążeń wiatrem na podstawie norm projektowych i analizy przepływu CFD
    • Robert Okoński
    • Andrzej Ambroziak
    2022 Full text Przegląd Budowlany

    W pracy poruszono tematykę wykorzystania analizy przepływu CFD do wyznaczania obciążeń wiatru na konstrukcje. Przedstawiono analizę trzech modeli budynków o dachu dwuspadowym o różnych kątach nachylenia, dla których dokonano porównania wielkości współczynników parcia z wynikami dostępnymi w literaurze. Obliczenia analityczne wykonano zgodnie z normą z PN-EN 1991-1-4, natomiast obliczenia numeryczne wykonano w programie R-Wind Simulation. Całość wyników podsumowano, a wnioski sformułowano w odniesieniu do tematyki rozwiązania problemu szacowania wielkości obciążenia wiatru działającego na konstrukcję.

  • Analiza przyczepności prętów żebrowanych w betonie metodą pull-out na próbkach centrycznych i mimośrodowych
    • Marcin Burdziński
    • Maciej Niedostatkiewicz
    2022 Full text Przegląd Budowlany

    Artykuł dotyczy analizy przyczepności żebrowanego stalowego pręta zbrojeniowego w betonie. Celem pracy była ocena wpływu położenia pręta w betonowym bloku na lokalną zależność naprężenie przyczepności-poślizg. Podjęto także próbę numerycznej symulacji przeprowadzonych eksperymentów w programie ABAQUS. Analizę doświadczalną przeprowadzono za pomocą testu pull-out na dwóch rodzajach próbek – centrycznych i mimośrodowych w dwóch wariantach, z dolnym otuleniem o grubości 20 i 40 mm. Do obliczeń numerycznych wykorzystano modele materiałowe odpowiadające materiałom zastosowanym w doświadczeniach. Użyto modelu betonu plastycznego ze zniszczeniem (ang. Concrete Damaged Plasticity) oraz modelu liniowo-sprężystego dla stali. Przeprowadzone eksperymenty potwierdziły, że zmiana lokalizacji pręta na kierunku pionowym wpływa na zmniejszenie jego skrępowania w betonie, co rzutuje na redukcję wartości maksymalnych naprężeń przyczepności oraz na mechanizm zniszczenia, czego konsekwencją jest zmiana przebiegu krzywej naprężenie przyczepności-poślizg względem próbek centrycznych. Wykonane symulacje MES poprawnie odwzorowują zachowanie przyczepności w próbkach podczas testów pull-out.

  • ANALIZA STATECZNOŚCI ORAZ KONCEPCJA ZABEZPIECZENIA ZBOCZA OSUWISKOWEGO W MOSTKACH K. STAREGO SĄCZA
    • Lesław Zabuski
    • Jarosław Przewłócki
    2022 Rozprawy Naukowe i Zawodowe Państwowej Wyższej Szkoły Zawodowej w Elblągu

    W artykule przedstawiano analizę warunków stateczności zbocza osuwiskowego w miejscowości Mostki k. Starego Sącza, wraz ze sprawdzeniem efektywności zabezpieczenia zbocza przy zastosowaniu środków stabilizujących. Dla ustabilizowania zbocza zaproponowano jego drenowanie (drenaż podziemny) oraz „podparcie” przegrodą z mikropali. Rozważano stan stateczności zbocza w warunkach ekstremalnie niekorzystnych - gdy zwierciadło wody podziemnej (ZWP) osiąga poziom powierzchni terenu oraz po zastosowaniu środków stabilizujących.

  • ANALIZA ZANIKÓW SZYBKOZMIENNYCH W RADIOWYCH SIECIACH BAN PRACUJĄCYCH W REWERBERACYJNYM ŚRODOWISKU PROPAGACYJNYM
    • Sławomir Ambroziak
    • Filipe D. Cardoso
    • Paweł Kosz
    • Manuel M. Ferreira
    • Luis M. Correia
    2022 Full text Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    W referacie przedstawiono badania i analizę zaników szybkozmiennych występujących w sieciach BAN, pracujących na częstotliwości 2,45 GHz w środowisku zamkniętym o kształcie cylindrycznym z metalowymi ścianami. Badania przeprowadzono przy użyciu symulatora zweryfikowanego pomiarowo. Uzyskane wyniki wskazują, że w analizowanym środowisku propagacyjnym zaniki szybkozmienne można modelować przy pomocy rozkładu Rayleigha, nawet w przypadku występowania warunków bezpośredniej widoczności anten łącza radiowego.

  • Analyses of Shear Angle in Orthogonal Cutting of Pine Wood
    • Kazimierz Orłowski
    • Daniel Chuchała
    • Gerhard Sinn
    2022 Full text Drvna Industrija

    The determination of energy effects for wood machining processes, such as cutting power and cutting forces, is very useful in designing of manufacture process of wooden products. A more accurate prediction of cutting forces requires a correct determination of the shear angle value, which can be determined using various models. In this article, shear angle values for an orthogonal linear cutting process of pine wood are determined. The pine wood analysed was represented by two groups of samples with different moisture content levels, 12 % and 20 %. Three different models were used to determine the shear angle values: the Merchant model, which is based on the rake angle and the angle of friction, model based on chip compression ratios and Atkins model based on material properties (elements of fracture mechanics). The values obtained have been analysed for comparison. Results showed that the values of the shearing angles determined from the chip compression ratios turned out to be higher than the values from Merchant equation. The shear angles determined from the Atkins model are, as expected, lower than those determined from the Merchant model. Furthermore, the shear angle values for moisture content of 20 % are higher than for moisture content of 12 %.

  • Analysing By-Products Interaction as an Industry Resource of Circular Economy in Ukraine and the World
    • Myroslava Bublyk
    • Vadym Shandurskyi
    • Taras Machita
    • Piotr Grudowski
    • Oleksandr Pavlyuk
    2022

    The paper analyses existing and current scientific developments and literature sources, which show the advantages and disadvantages of many different influences of waste in Ukraine and other countries of Europe and the world. As a research result, stable connections have been established between the factors and criteria in assessing the by-product interaction as an industry resource. In our research, we used programs R.Studio and Power BI Desktop, and language programming R. Analysis dataset conducted by help such diagrams as Histogram, Pie Charts. Based on the analysis diagrams, we conducted our analysis, where we determined the main factors and criteria.

  • Analysing the Residential Market Using Self-Organizing Map
    • Olgun Aydin
    • Krystian Zieliński
    2022

    Although the residential property market has strong connections with various sectors, such as construction, logistics, and investment, it works through different dynamics than other markets; thus, it can be analysed from various perspectives. Researchers and investors are mostly interested in price trends, the impact of external factors on residential property prices, and price prediction. When analysing price trends, it is beneficial to consider multidimensional data that contain attributes of residential properties, such as number of rooms, number of bathrooms, floor number, total floors, and size, as well as proximity to public transport, shops, and banks. Knowing a neighbourhood’s key aspects and properties could help investors, real estate development companies, and people looking to buy or rent properties to investigate similar neighbourhoods that may have unusual price trends. In this study, the self-organizing map method was applied to residential property listings in the Trójmiasto Area of Poland, where the residential market has recently been quite active. The study aims to group together neighbourhoods and subregions to find similarities between them in terms of price trends and stock. Moreover, this study presents relationships between attributes of residential properties.

  • Analysis of Agricultural and Engineering Systems using Simulation Decomposition
    • Yen-Chen Liu
    • Leifur Leifsson
    • Anna Pietrenko-Dąbrowska
    • Sławomir Kozieł
    2022

    This paper focuses on the analysis of agricultural and engineering processes using simulation decomposition (SD). SD is a technique that utilizes Monte Carlo simulations and distribution decomposition to visually evaluate the source and the outcome of different portions of data. Here, SD is applied to three distinct processes: a model problem, a nondestructive evaluation testing system, and an agricultural food-water energy system. The results demonstrate successful implementations of SD for the different systems, and the illustrate the potential of SD to support new understanding of cause and effect relationships in complex systems.

  • Analysis of an Energy Management System of a Small Plant Connected to the Rural Power System
    • Mirosław Włas
    • Stanisław Galla
    • Abdellah Kouzou
    • Piotr Kołodziejek
    2022 Full text ENERGIES

    This paper presents the analysis of an energy management system (EMS) implemented to fulfill the requirements of a microgrid (MG) power supply owned by a small industrial company and connected to the rural power system. The main goal of this system is to ensure connection with the existing rural power system in terms of energy exchange, as well as to perform islanding mode operation of the microgrid based on the energy demand of the company. Power generated in the implemented microgrid is based on a hybrid system supported by renewable energy sources and an energy storage system. The aim of the developed energy management system implemented in this MG power system is to enable the microgrid to operate according to scheduled diagrams related to different load events. The presented investigation, analysis, and assessment of the implemented energy management system are based on the on-site measurements and observations of the longterm operation of the microgrid concerning the hybrid renewable energy-based generation system and the company energy demand, which is useful from perspective of the predicted deficiency of electrical energy in Poland, both for customers and transmission system operators. Furthermore, the observed drawbacks and failures of the implemented EMS and the MG are pointed out and discussed to overcome and minimize these disadvantages, and to improve the operational reliability of the whole system.

  • Analysis of data fusion algorithms for the vessel with the dynamic positioning system
    • Krzysztof Jaroś
    • Roman Śmierzchalski
    • Anna Witkowska
    2022 Full text Przegląd Elektrotechniczny

    The dynamic positioning (DP) system on the vessel is operated to control the position and heading of the vessel with the use of propellers and thrusters installed on the board. On DP vessels redundant measurement systems of position, heading and the magnitude and direction of environmental forces are required for safety at sea. In this case, a fusion of data is needed from individual measurement devices. The article proposes a new solution data fusion algorithm of particle Kalman filter as a cascade combination of particle filter and extended Kalman filter. The estimation quality of the proposed data fusion algorithm is analysed in comparison with the classic: extended Kalman filter (EKF), nonlinear observer (NO), and particle Kalman filter (PKF). Simulation studies were executed for emergency scenarios to evaluate the robustness of the algorithm analyses to measurement errors.

  • Analysis of exhaled breath for dengue disease detection by low-cost electronic nose system
    • Janusz Smulko
    • Tomasz Chludziński
    • Tomasz Majchrzak
    • Andrzej Kwiatkowski
    • Sebastian Borys
    • Aylen Lisset Jaimes-Mogollón
    • Cristhian Manuel Durán-Acevedo
    • Omar Geovanny Perez-Ortiz
    • Radu Ionescu
    2022 Full text MEASUREMENT

    This paper presents a procedure and a set-up of an electronic nose system analyzing exhaled breath to detect the patients suffering from dengue – a mosquito-borne tropical disease. Low-power resistive gas sensors (MiCS-6814, TGS8100) were used to detect volatile organic compounds (VOCs) in the exhaled breath. The end-tidal phase of patients exhaled breath was collected with a BioVOCTM breath sampler. Two strategies were assessed for breath samples measurement: either direct transfer from the BioVOCTM into the sensors test chamber, or storage in Tenax TA sorbent tubes followed by VOCs release through thermal desorption and then transfer into sensors test chamber. DC sensor resistances were recorded and processed by multivariate classifier algorithms to detect infected patients. The experimental studies were run on a group of 26 individuals (16 dengue diagnosed patients and 10 control volunteers). The detection accuracy of dengue patients was over 90%.

  • Analysis of Factors Influencing the Prices of Tourist Offers
    • Agata Kołakowska
    • Magdalena Godlewska
    2022 Full text Applied Sciences-Basel

    Tourism is a significant branch of many world economies. Many factors influence the volume of tourist traffic and the prices of trips. There are factors that clearly affect tourism, such as COVID-19. The paper describes the methods of machine learning and process mining that allow for assessing the impact of various factors (micro, mezzo and macro) on the prices of tourist offers. The methods were used on large sets of real data from two tour operators, and the results of these studies are discussed in this paper. The research presented is part of a larger project aiming at predicting trip prices. It answers the question of which factors have the greatest impact on the price and which can be omitted in further work. Nevertheless, the dynamic world situation suggests that the ranking of factors may change and the presented universal methods may provide different results in the coming years.

  • Analysis of floor-to-column pounding of buildings founded on different soil types
    • Mahmoud Miari
    • Robert Jankowski
    2022 Full text Bulletin of Earthquake Engineering

    The aim of this study is to investigate the effect of the soil type on buildings experiencing floor-to-column pounding during earthquakes. Five buildings with 4-storeys, 6-storeys, and 7-storeys were considered. Three types of the 4-storey building with different total heights were taken into account which leads to floor-to-column pounding at 1/3, 1/2 and 2/3 of the height of the impacted column. Two pounding scenarios were considered, i.e. pounding between the 4-storey and 6-storey buildings (three cases when collisions occur at 1/3, 1/2 and 2/3 of the height of the impacted column) and pounding between the 4-storey and 7-storey buildings (three cases when collisions occur at 1/3, 1/2 and 2/3 of the height of the impacted column). In the first part of this study, the shear demands of the columns at the contact area were studied and compared with the no pounding case to investigate the effect of the floor-to-column pounding. Then, the shear demands of the columns at the contact area were studied for buildings founded on different soil types to investigate the effect of the soil type on the structural response. The results of this study illustrate that the shear demands of the impacted column significantly increase due to collisions and it exceeds the shear strength in all cases. Moreover, impacted column experiences higher shear demands for buildings founded on the soft clay soil, then for buildings founded on the stiff soil, then for buildings founded on very dense soil and soft rock, and finally for buildings founded on the rock and hard rock.

  • Analysis of human behavioral patterns
    • Agata Kołakowska
    2022

    Widespread usage of Internet and mobile devices entailed growing requirements concerning security which in turn brought about development of biometric methods. However, a specially designed biometric system may infer more about users than just verifying their identity. Proper analysis of users’ characteristics may also tell much about their skills, preferences, feelings. This chapter presents biometric methods applied in several areas, such as user authentication, emotion recognition, diagnosis and therapy of disorders. The presented algorithms mainly focus on behavioral biometrics based on data from standard input devices.

  • Analysis of Impulse Responses Measured in Motion in a Towing Tank
    • Agnieszka Czapiewska
    • Andrzej Łuksza
    • Ryszard Studański
    • Andrzej Żak
    2022 Full text Electronics

    The growing interest in developing autonomous underwater vehicles (AUVs) and creating underwater sensor networks (USNs) has led to a need for communication tools in underwater environments. For obvious reasons, wireless means of communication are the most desirable. However, conducting research in real conditions is troublesome and costly. Moreover, as hydroacoustic propagation conditions change very significantly, even during the day, the assessment of proposed underwater wireless communication methods is very difficult. Therefore, in the literature, there are considered simulators based on real measurements of underwater acoustic (UWA) channels. However, these simulators make an assumption that, during the transmission of elementary signals, the impulse response does not change. In this article, the authors present the results of the measurements realized in a towing tank where the transmitter could move with a precisely set velocity and show that the analyzed channel was non-stationary, even during the time of the transmission of a single chirp signal. The article presents an evaluation method of channel stationarity at the time of the chirp transmission, which should be treated as novelty. There is also an analysis of the impulse responses measured in motion in a towing tank.

  • Analysis of Methods for Determining Shallow Waterbody Depths Based on Images Taken by Unmanned Aerial Vehicles
    • Mariusz Specht
    • Marta Wiśniewska
    • Andrzej Stateczny
    • Cezary Specht
    • Bartosz Szostak
    • Oktawia Lewicka
    • Marcin Stateczny
    • Szymon Widźgowski
    • Armin Halicki
    2022 Full text SENSORS

    Hydrographic surveys enable the acquisition and processing of bathymetric data, which after being plotted onto nautical charts, can help to ensure safety of navigation, monitor changes in the coastal zone, and assess hydro-engineering structure conditions. This study involves the measurement of waterbody depth, identification of the seabed shape and geomorphology, the coastline course, and the location of underwater obstacles. Hydroacoustic systems mounted on vessels are commonly used in bathymetric measurements. However, there is also an increasing use of Unmanned Aerial Vehicles (UAV) that can employ sensors such as LiDAR (Light Detection And Ranging) or cameras previously not applied in hydrography. Current systems based on photogrammetric and remote sensing methods enable the determination of shallow waterbody depth with no human intervention and, thus, significantly reduce the duration of measurements, especially when surveying large waterbodies. The aim of this publication is to present and compare methods for determining shallow waterbody depths based on an analysis of images taken by UAVs. The perspective demonstrates that photogrammetric techniques based on the SfM (Structure-from-Motion) and MVS (Multi-View Stereo) method allow high accuracies of depth measurements to be obtained. Errors due to the phenomenon of water-wave refraction remain the main limitation of these techniques. It was also proven that image processing based on the SfM-MVS method can be effectively combined with other measurement methods that enable the experimental determination of the parameters of signal propagation in water. The publication also points out that the Lyzenga, Satellite-Derived Bathymetry (SDB), and Stumpf methods allow satisfactory depth measurement results to be obtained. However, they require further testing, as do methods using the optical wave propagation properties.

  • Analysis of Organic Rankine Cycle efficiency and vapor generator heat transfer surface in function of the reduced pressure
    • Dariusz Mikielewicz
    • Jarosław Mikielewicz
    2022 Full text ENERGY

    In the paper presented is analysis of the influence of reduced pressure on efficiency and heat transfer area of vapor generator of Organic Rankine Cycle (ORC) in case of subcritical and supercritical parameters of operation. Compared are two cases of subcritical and supercritical ORC featuring a similar arrangement of heat source supply and heat removal, that is featuring the same temperatures of working fluid before the turbine, and the same condensation temperature in the respective cycles. The analysis is helpful in selection of the appropriate pressure in the vapor generator. In accomplished analyses a selection of wet ORC working fluids are scrutinized for a given range of heat source temperatures with respect to influence on efficiency of thermodynamic cycle and vapor generator area of heat transfer on installation and operation costs to illustrate the issue. Investment cost of a vapor generator in the ORC cycle accounts for a main share of expenditure alongside the cost of the expanding machine. Results of calculations show that from the point of view of cycle efficiency and size of vapor generator the pressures close to critical fluid pressure are usually optimal. Some working fluids feature even an optimal pressure. For the region close to critical point authors elaborated own method for heat transfer coefficients elaboration, which is useful in more exact estimations of heat transfer process in vapor generator. In case of a heat source with a relatively high temperature, it is better to consider a thermodynamic cycle with supercritical parameters even if as a result the vapor generator is slightly larger than for the case of a subcritical cycle. There will always be a more pronounced gain in efficiency compared to the expense induced by the heat transfer surface area of vapor generator.

  • Analysis of pounding between adjacent buildings founded on different soil types
    • Mahmoud Miari
    • Robert Jankowski
    2022 SOIL DYNAMICS AND EARTHQUAKE ENGINEERING

    Earthquake-induced pounding was experienced in many previous earthquakes and it was found to be a critical issue. This study investigates the effect of pounding between buildings founded on the same and different soil types. Three 3-D buildings with 4, 6 and 8 storeys were considered in this study. Three pounding scenarios were taken into account, i.e. pounding between 4-storey and 6-storey buildings, between 4-storey and 8-storey buildings and between 6-storey and 8-storey buildings. To consider the soil type, the effects of different site parameters on the response of buildings exposed to earthquakes was firstly investigated so that the values that lead to significant effects and larger responses could be taken into account in further study related to structural interactions. In the next stage of the investigation, the effects of pounding between buildings founded on a specified soil type were analysed and compared with the no pounding case. The results of this part of this study show that pounding significantly increases the peak accelerations in all situations. Indeed, the peak displacements experience both amplification and de-amplification. Moreover, the shear forces were found to be increased for all storeys in all the cases with few exceptions concerning the top storeys. Finally, pounding between 4-storey and 8-storey buildings as well as between 6-storey and 8-storey buildings was considered under different soil types defined in the ASCE 7-10 code (hard rock, rock, very dense soil and soft rock, stiff soil and soft clay soil). The results of this stage of this study show that the highest displacements and shear forces can be expected for buildings founded on the soft clay soil, then for buildings founded on the stiff soil, then for buildings founded on very dense soil and soft rock, and finally for buildings founded on the rock and hard rock.

  • Analysis of the Factors Affecting Static In Vitro Pepsinolysis of Food Proteins
    • Natsumi Maeda
    • Dorota Dulko
    • Adam Macierzanka
    • Christian Jungnickel
    2022 Full text MOLECULES

    In this meta-analysis, we collected 58 publications spanning the last seven decades that reported static in vitro protein gastric digestion results. A number of descriptors of the pepsinolysis process were extracted, including protein type; pepsin activity and concentration; protein concentration; pH; additives; protein form (e.g., ‘native’, ‘emulsion’, ‘gel’, etc.); molecular weight of the protein; treatment; temperature; and half-times (HT) of protein digestion. After careful analysis and the application of statistical techniques and regression models, several general conclusions could be extracted from the data. The protein form to digest the fastest was ‘emulsion’. The rate of pepsinolysis in the emulsion was largely independent of the protein type, whereas the gastric digestion of the native protein in the solution was strongly dependent on the protein type. The pepsinolysis was shown to be strongly dependent on the structural components of the proteins digested—specifically, -sheet-inhibited and amino acid, leucine, methionine, and proline-promoted digestion. Interestingly, we found that additives included in the digestion mix to alter protein hydrolysis had, in general, a negligible effect in comparison to the clear importance of the protein form or additional treatment. Overall, the findings allowed for the targeted creation of foods for fast or slow protein digestion, depending on the nutritional needs.

  • Analysis of the Hydrodynamic Properties of the 3-Column Spar Platform for Offshore Wind Turbines
    • Ewelina Ciba
    • Paweł Dymarski
    • Mirosław Grygorowicz
    2022 Full text Polish Maritime Research

    The article presents a design of a floating platform for offshore wind turbines. The concept is a modification of the Spar design and consists of three variable section columns connected to each other by a ballast tank in the lower part of the platform. This solution makes it possible to influence the position of the centre of buoyancy and the centre of mass of the structure. Compared to the classic Spar platform structure, the centre of buoyancy can be higher than mid-draft, which will provide the platform with greater stability. At the same time, this concept is better, in terms of technology, because of its modular structure and smaller bending radii.On the basis of the model testing performed, the hydrodynamic coefficients of the designed platform and its response to a given regular wave were determined (the transfer functions for heave and pitch motion were determined). Then, based on the damping coefficients, the platform was modelled in the ANSYS AQWA program and the results were very similar.

  • Analysis of the influence of external conditions on temperature readings in thermograms and adaptive adjustment of the measured temperature value
    • Piotr Filipowicz
    • Mateusz Kowalewski
    • Kinga Słomińska
    • Mariusz Kaczmarek
    2022

    Measuring human temperature is a crucial step in preventing the spread of diseases such as COVID-19. For the proper operation of an automatic body temperature measurement system throughout the year, it is necessary to consider outdoor conditions. In this paper, the effect of atmospheric factors on facial temperature readings using infrared thermography is investigated. A thorough analysis of the variation of facial temperature with the prevailing atmospheric conditions was carried out using recordings collected over two years and compared with air temperature values at 1 hour accuracy. A method that takes account of outdoor conditions on temperature readings was proposed. We developed a correction curve with coefficients values based on an analysis of the recordings of people entering the building. Such a method will allow an effective real-time fever screening in public places.

  • Analysis of the influence of polystyrene microplastics and their derivatives on the DNA of human colon epithelial cells HT29 with the comet assay
    • Paweł Filipkowski
    • Aleksandra Ćwiklińska
    • Zuzanna Koziara
    • Karol Parchem
    • Łukasz Zedler
    • Jacek Ryl
    2022 Full text Research Square

    We have been using plastic for almost a century and nowadays a lot of them circulates as pollutants in the environment and still defragmenting to micro and nanoscale. The exposition through the food chain and its precise impact on human health is still not clear. In our study, we tested real food packaging after contact with food products and real thermoinsulation and environmental samples of polystyrene in different model liquids, We used a comet assay, mass spectrometry (MS) of fluids which were in contact with packaging, free styrene measurement by Wijs method according to ISO standard and FTIR of wrap, to get an overview of their possible harmful effects. In the presented study, only low genotoxic effect (5-6% DNA damage) was observed.. In addition, no adverse effects were detected in the mass spectrometry. For analysed coloured polystyrene food packaging materials, we noticed a lower level of free styrene monomers in dairy packages that originally contained products with fruits. Exposure of cells to long-term seasoned polystyrene caused less DNA fragmentation than in the case of samples in saline.. Unfortunately, to this day no one knows how much free styrene and derivatives we eat with our daily food products and from food packaging. Based on our results and knowledge, more attention is needed with regard to polystyrene contamination. In particular, a wider analysis of the impact of interactions with the microbiota and the food matrix, which is in direct contact with the polystyrene packaging, should be carried out. The results of our research show that polystyrene and its derivatives from food packaging can potentially have a negative effect on the DNA of human colon epithelial cells. We recommend seasoning of freshly formed polystyrene products and increasing personal protection in relation to workers of the polystyrene foaming factories This applies primarily to dairy products, readily consumed by children, which are rich in both organic acids and salts, and the presence of these ingredients enhances the genotoxic effects. According to our best knowledge, this is the first study using actual polystyrene food packaging available on the market.

  • Analysis of Transformation Methods of Hydroacoustic and Optoelectronic Data Based on the Tombolo Measurement Campaign in Sopot
    • Oktawia Lewicka
    • Mariusz Specht
    • Andrzej Stateczny
    • Cezary Specht
    • Czesław Dyrcz
    • Paweł Dąbrowski
    • Bartosz Szostak
    • Armin Halicki
    • Marcin Stateczny
    • Szymon Widźgowski
    2022 Full text Remote Sensing

    Measurements in the coastal zone are carried out using various methods, including Global Navigation Satellite Systems (GNSS), hydroacoustic and optoelectronic methods. Therefore, it is necessary to develop coordinate transformation models that will enable the conversion of data from the land and marine parts to one coordinate system. The article presents selected issues related to the integration of geodetic and hydrographic data. The aim of this publication is to present the various transformation methods and their effects that relate to the data from the tombolo measurement campaign in Sopot conducted in 2018. Data obtained using GNSS Real Time Kinematic (RTK) measurements, Terrestrial Laser Scanning (TLS), the Unmanned Aerial Vehicle (UAV) and the Unmanned Surface Vehicle (USV) were transformed. On the basis of the coordinate transformation methods used, it can be concluded that the adjustment calculus method obtained the best results for the plane coordinates, while the method of P.S. Dąbrowski et al. obtained the best results for the height coordinates. The standard deviation for the difference of the modelled coordinates acquired by the method of P.S. Dąbrowski et al. with respect to the reference coordinates amounted to: 0.022 m (Northing), 0.040 m (Easting) and 0.019 m (height), respectively, while the adjustment calculus method allowed to obtain the following values: 0.009 m (Northing), 0.005 m (Easting) and 0.359 m (height). It can be assumed that a combination of these two seven-parameter transformation methods would provide the best results. In the future, a new seven-parameter transformation method should be developed based on the synthesis of these two existing methods.

  • Analysis of Video Transmission Capabilities in a Simulated OFDM-Based Supplementary BPL-PLC System
    • Grzegorz Debita
    • Przemysław Falkowski-Gilski
    • Monika Zamłyńska
    • Marcin Habrych
    • Bogdan Miedziński
    • Teresa Kupczyk
    • Bartosz Polnik
    2022 Full text ENERGIES

    The design and maintenance of a reliable communication system, especially in harsh working conditions for the oil and mining industry, brings many challenges. With the use of a video transmission system, one can monitor the crew and their working environment. Broadband over power line–power line communication (BPL-PLC) seems an ideal medium for such a service, since it enables the use of the existing wired infrastructure for supplementary applications. In this paper, we perform a set of simulations for a dedicated wired medium as well as analyses of a visual data transmission system, designed to deliver video content with quadrature amplitude modulation (QAM) and orthogonal frequency division multiplexing (OFDM). We investigate a set of video sequences at 480 × 270 resolution under varying network conditions, including signal-to-noise ratio (SNR) and bit error rate (BER). We perform a subjective evaluation study of video content transmitted over our simulated communication link. The results of this study may aid parties involved in designing additional services for portable devices and user terminals, including reliable means of contact, surveillance and monitoring. The obtained results may be of particular interest to researchers and professionals related to the Industry 4.0 and Internet of things (IoT) concepts.

  • Analysis-by-synthesis paradigm evolved into a new concept
    • Bożena Kostek
    2022 Journal of the Acoustical Society of America

    This work aims at showing how the well-known analysis-by-synthesis paradigm has recently been evolved into a new concept. However, in contrast to the original idea stating that the created sound should not fail to pass the foolproof synthesis test, the recent development is a consequence of the need to create new data. Deep learning models are greedy algorithms requiring a vast amount of data that, in addition, should be correctly annotated. Annotation is a bottleneck to getting quality-reliable data as the process relies on annotating a person’s experience and, in many cases, personality related issues. So, the new approach is to create synthesized data based on a thorough analytical examination of a musical/speech signal resulting in cues for a deep model of how to populate data to overcome this problem. Typically, a 2D feature space is employed, e.g., mel spectrograms, cepstrograms, chromagrams, etc., or a wave-based representation with the counterpart on the algorithmic side called wavenet. In this paper, examples of 2D musical/ speech signal representation are presented, along with deep models applied. Creating new data in the ontext of applications is also shown. In conclusion, further possible directions of this paradigm development which is now beyond the conceptual phase, are presented.

  • Analytical chemistry in technical approaches: immobilization of biosorbent waste containing heavy metals in cemented materials
    • Rahmiana Zein
    • Syiffa Fauzia
    • Zuzanna Bielan
    • Hermansyah Aziz
    • Dahyunir Dahlan
    • Piotr Konieczka
    • Bartłomiej Cieślik
    2022 Full text MONATSHEFTE FUR CHEMIE

    An ecologically safe and economically justified method of stabilization of the used biosorbents was developed. Sorbent contaminated with heavy metals has been successfully solidified/stabilized using a hydraulic binder. The test results indicated that up to 1% of the biosorbent residue used could be added without compromising the compressive strength of the mortar. The compressive strength of the modified mortars did not change significantly even after 20 freeze/thaw cycles. The analytical methods such as Flame Atomization-Atomic Absorption Spectrometer, Graphite Furnace-Atomic Absorption Spectrometer, and Cold Vapor-Atomic Absorption Spectrometry were utilized to examine the leaching behavior of selected heavy metals during harsh condition exposure. The leachability of selected heavy metals was found to be below the limit allowed by the US EPA after immersion and agitation for 10 days in artificial water solutions (seawater, groundwater, and rainwater). X-Ray Diffraction and Brunauer–Emmett–Teller data showed no significant changes in the crystalline structure and surface area of the modified mortars after treatment. Research showed that mixing the adsorbent used with mortar was effective in immobilizing heavy metals and allowed the implementation of a so-called ‘zero waste’ management method.

  • Analytical Estimation of Power Losses in a Dual Active Bridge Converter Controlled with a Single-Phase Shift Switching Scheme
    • Marek Turzyński
    • Serafin Bachman
    • Marek Jasiński
    • Szymon Piasecki
    • Marek Ryłko
    • Huang-Jen Chiu
    • Shih-hao Kuo
    • Yu-Chen Chang
    2022 Full text ENERGIES

    Micro-grid solutions around the world rely on the operation of DC/DC power conver- sion systems. The most commonly used solution for these topologies is the use of a dual active bridge (DAB) converter. Increasing the efficiency and reliability of this system contributes to the improvement in the stability of the entire microgrid. This paper discussed an analytical method of energy efficiency and power loss estimation in a single phase dual active bridge (DAB) converter controlled with a single-phase shift (SPS) modulation scheme for microgrid system stability. The presented approach uses conduction and commutation losses of semiconductors and high frequency transformer. All parameters required for the calculation may be obtained from the manufacturers’ datasheets or can be based on a simple measurement. The approach was validated by the comparison of the estimated energy efficiency characteristics with the measured ones for a prototype of a 5 kW single phase DAB converter equipped with silicon carbide metal-oxide semiconductor field-effect transistors (SiC MOSFET)

  • Analytical Methods for Causality Evaluation of Photonic Materials
    • Tomasz Stefański
    • Jacek Gulgowski
    • Kosmas L. Tsakmakidis
    2022 Full text Materials

    We comprehensively review several general methods and analytical tools used for causality evaluation of photonic materials. Our objective is to call to mind and then formulate, on a mathematically rigorous basis, a set of theorems which can answer the question whether a considered material model is causal or not. For this purpose, a set of various distributional theorems presented in literature is collected as the distributional version of the Titchmarsh theorem, allowing for evaluation of causality in complicated electromagnetic systems. Furthermore, we correct the existing material models with the use of distribution theory in order to obtain their causal formulations. In addition to the well-known Kramers–Krönig (K–K) relations, we overview four further methods which can be used to assess causality of given dispersion relations, when calculations of integrals involved in the K–K relations are challenging or even impossible. Depending on the given problem, optimal approaches allowing us to prove either the causality or lack thereof are pointed out. These methodologies should be useful for scientists and engineers analyzing causality problems in electrodynamics and optics, particularly with regard to photonic materials, when the involved mathematical distributions have to be invoked.

  • Analytical Traffic Model for a Multidomain IMS/NGN Network Including Service and Transport Stratum
    • Sylwester Kaczmarek
    • Maciej Sac
    • Michał Cieśliński
    2022

    This paper addresses the problem of modelling call processing performance (CPP) in a multidomain Next Generation Network (NGN) architecture including the elements of the IP Multimedia Subsystem (IMS) in service stratum and based on the Multiprotocol Label Switching (MPLS) technology in transport stratum. An analytical traffic model for such an architecture is proposed by integrating the formerly implemented submodels of service stratum and MPLS-based transport stratum. The integrated analytical model allows investigation of mean Call Set-up Delay (E(CSD)) and mean Call Disengagement Delay (E(CDD)) for a large set of input variables corresponding to both IMS/NGN strata. The evaluation of E(CSD) and E(CDD), which are a subset of CPP parameters, is very important for both network users and operators. Details regarding the structure and operation of the integrated traffic model are provided in this paper. Moreover, the results of investigations are described, which demonstrate that this model is correctly implemented, reflects the operation of a multidomain IMS/NGN network and may be used in further research.

  • Analyzing Wind Energy Potential Using Efficient Global Optimization: A Case Study for the City Gdańsk in Poland
    • Olgun Aydin
    • Bartłomiej Igliński
    • Krzysztof Krukowski
    • Marek Siemiński
    2022 Full text ENERGIES

    Wind energy (WE), which is one of the renewable energy (RE) sources for generating electricity, has been making a significant contribution to obtaining clean and green energy in recent years. Fitting an appropriate statistical distribution to the wind speed (WS) data is crucial in analyzing and estimating WE potential. Once the best suitable statistical distribution for WS data is determined, WE potential and potential yield could be estimated with high accuracy. The main objective of this paper is to propose a novel approach for calculating wind energy potential. For this purpose, the Efficient Global Optimization (EGO) technique was proposed for fitting a statistical distribution to WS data and the performance of the technique was compared with genetic algorithm (GA), simulated annealing (SA), and differential evolution (DE). Performance metrics showed that EGO is providing better estimations compared with GA, SA, and DE. Based on Weibull parameters obtained by using EGO, potential WE and potential annual revenue were estimated for Gdańsk, which is the capital of Pomerania Voivodeship in Poland, in the case of having city-type wind turbines in the city center. Estimations for Gdańsk showed that city-type wind turbines might be helpful for producing electricity from WE in the city without being limited by constraints such as having a long distance between wind turbines and buildings. If such wind turbines were erected on the roofs of residential buildings, malls, or office buildings, there is a possibility that part of the electric energy needed for such buildings could be generated using WE. However, this topic should be further investigated from technical and financial perspectives

  • Anionic states of C6Cl6 probed in electron transfer experiments
    • Sarvesh Kumar
    • Tymon Kilich
    • Marta Łabuda
    • Gustavo García
    • Paulo Limão-Vieira
    2022 Full text PHYSICAL CHEMISTRY CHEMICAL PHYSICS

    This is the first comprehensive investigation on the anionic species formed in collisions of fast neutral potassium (K) atoms with neutral hexachlorobenzene (C6Cl6) molecules in the laboratory frame range from 10 up to 100 eV. In such ion-pair formation experiments, we also report a novel K+ energy loss spectrum obtained in the forward scattering giving evidence of the most accessible electronic states. The vertical electron affinity of (–3.76 ± 0.20) eV has been obtained and assigned to a purely repulsive transition from C6Cl6 ground state to a σCCl*state of the temporary negative ion yielding Cl– formation. These experimental findings have also been supported by state-of-the art theoretical calculations on the electronic structure of C6Cl6 in the presence of a potassium atom and used to help analyse the lowest unoccupied molecular orbitals participating in the collision process. From the time-of-flight mass spectra recorded in the wide collision energy range, more than 80% of the total anion yield is due to the undissociated parent anion C6Cl6 –, C6Cl5 – and Cl– formation. Other fragment anions that require complex internal reactions within the temporary negative ion formed after electron transfer, and accounting for less than 20% of the total yield, have been assigned to C6Cl4–, C3Cl2–, C2Cl– and Cl2–. The joint experimental and theoretical methodologies employed in these electron transfer studies, are the most comprehensive and unique assignments of the hexachlorobenzene anionic species and the role of C6Cl6 electronic states in collision induced dissociation to date.

  • Anonymus
    • Krzysztof Wróblewski
    2022

    Impulsem do namalowania niewielkiego obrazu „Anonymous” były akcje przeprowadzone przez internetowe grupy hakerów, których celem było wspomagania Ukrainy w jej walce przeciwko militarnej agresji Rosji. Anonimowi aktywiści ukrywają twarze pod maską Guya Fawkesa, która rozpowszechniła się po 2006 roku wśród różnych grup protestacyjnych występujących przeciwko rządom, bankom i instytucjom finansowym. Maska chroni nie tylko tożsamość buntowników, ale symbolizuje też ich zjednoczenie we wspólnej sprawie. Aktywiści Anonymous nie są anarchistami lecz rebeliantami, którzy sprzeciwiają się ograniczaniu wolności oraz agresji. Świat tworzą i zmieniają dłonie miliardów ludzi, których twarze przybiera ją wielorakie maski. Skala ich dokonań ma różne rozmiary – od prawie niewidocznych po gigantyczne.

  • Antibacterial Porous Systems Based on Polylactide Loaded with Amikacin
    • Marta Glinka
    • Katerina Filatova
    • Justyna Kucińska-Lipka
    • Tomáš Šopík
    • Eva Domincová Bergerová
    • Veronika Mikulcová
    • Andrzej Wasik
    • Vladimir Sedlařík
    2022 Full text MOLECULES

    Three porous matrices based on poly(lactic acid) are proposed herein for the controlled release of amikacin. The materials were fabricated by the method of spraying a surface liquid. Description is given as to the possibility of employing a modifier, such as a silica nanocarrier, for prolonging the release of amikacin, in addition to using chitosan to improve the properties of the materials, e.g., stability and sorption capacity. Depending on their actual composition, the materials exhibited varied efficacy for drug loading, as follows: 25.4 ± 2.2 µg/mg (matrices with 0.05% w/v of chitosan), 93 ± 13 µg/mg (with 0.08% w/v SiO2 amikacin modified nanoparticles), and 96 ± 34 µg/mg (matrices without functional additives). An in vitro study confirmed extended release of the drug (amikacin, over 60 days), carried out in accordance with the mathematical Kosmyer– Pepas model for all the materials tested. The matrices were also evaluated for their effectiveness in inhibiting the growth of bacteria such as Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Concurrent research was conducted on the transdermal absorption, morphology, elemental composition, and thermogravimetric properties of the released drug.

  • Antibacterial properties of laser-encapsulated titanium oxide nanotubes decorated with nanosilver and covered with chitosan/Eudragit polymers
    • Łukasz Pawłowski
    • Jakub Wawrzyniak
    • Adrianna Banach-Kopeć
    • Bartłomiej Cieślik
    • Kacper Jurak
    • Jakub Karczewski
    • Robert Tylingo
    • Katarzyna Siuzdak
    • Andrzej Zieliński
    2022 Full text Materials Science & Engineering C-Materials for Biological Applications

    To provide antibacterial properties, the titanium samples were subjected to electrochemical oxidation in the fluoride-containing diethylene glycol-based electrolyte to create a titanium oxide nanotubular surface. Afterward, the surface was covered by sputtering with silver 5 nm film, and the tops of the nanotubes were capped using laser treatment, resulting in an appearance of silver nanoparticles (AgNPs) of around 30 nm in diameter on such a modified surface. To ensure a controlled release of the bactericidal substance, the samples were additionally coated with a pH-sensitive chitosan/Eudragit 100 coating, also exhibiting bactericidal properties. The modified titanium samples were characterized using SEM, EDS, AFM, Raman, and XPS techniques. The wettability, corrosion properties, adhesion of the coating to the substrate, the release of AgNPs into solutions simulating body fluids at different pH, and antibacterial properties were further investigated. The obtained composite coatings were hydrophilic, adjacent to the surface, and corrosion-resistant. An increase in the amount of silver released as ions or metallic particles into a simulated body fluid solution at acidic pH was observed for modified samples with the biopolymer coating after three days of exposure avoiding burst effect. The proposed modification was effective against both Gram-positive and Gram-negative bacteria.

  • Antibiotic resistance in wastewater, does the context matter? Poland and Portugal as a case study
    • Ivone Vaz-moreira
    • Harnisz Monika
    • Joana Abreu-Silva
    • Rolbiecki Damian
    • Ewa Korzeniewska
    • Aneta Łuczkiewicz
    • Célia M Manaia
    • Grażyna Plaza
    2022 CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY

    Antibiotic resistance has been considered a major human health threat that may endanger the success of medicine. Recent studies have unveiled worldwide asymmetries of antibiotic resistance occurrence, being factors as diverse as climate, socioeconomic, or antibiotic use possible drivers of such asymmetric distribution. In Europe, where clinical antibiotic resistance is surveyed for more than 20 years, the European Center for Disease Prevention and Control (ECDC) consistently describes an increasing gradient from North-to-South and from West-to-East. This observation motivated the current perspective paper aiming to qualitatively compare two countries located at the extreme latitude of Europe and also at distant longitude – Poland in the Central-East region and Portugal in the South-West. Both countries have been among those with the highest prevalence of antibiotic resistance in clinical settings, although as it is discussed, climate, socioeconomic factors, and antibiotic use are different. In general, in Poland higher antibiotic consumption and resistance prevalence is observed, mainly at the community level, when compared to Portugal. However, in Portugal, treated wastewater may hold identical or slightly higher resistance loads. Based on these observations, it is discussed how different factors may influence the abundance of antibiotics, antibiotic resistant bacteria, and genes in wastewater before and after treatment.

  • Antibiotic resistance, virulence, and phylogenetic analysis of Escherichia coli strains isolated from free-living birds in human habitats
    • Bartosz Rybak
    • Beata Krawczyk
    • Beata Furmanek-Blaszk
    • Magdalena Wysocka
    • Magdalena Fordon
    • Pawel Ziolkowski
    • Wlodzimierz Meissner
    • Katarzyna Stepniewska
    • Katarzyna Sikorska
    2022 Full text PLOS ONE

    Wild birds can be colonized by bacteria, which are often resistant to antibiotics and have various virulence profiles. The aim of this study was to analyze antibiotic resistance mechanisms and virulence profiles in relation to the phylogenetic group of E. coli strains that were isolated from the GI tract of wildfowl. Out of 241 faecal samples, presence of E. coli resistant to a cephalosporin (ESBL/AmpC) was estimated for 33 isolates (13,7%). Based on the analysis of the coexistence of 4 genes encoding ESBLs/AmpC (blaCTX-M, blaTEM, blaSHV, blaAmpC) and class 1 and 2 integrons genes (intI1, intI2) a subset of two resistance profiles was observed among the investigated E. coli isolates carrying blaAmpC, blaSHV, and blaCTX-M, blaTEM, class 1 and 2 integrons, respectively. The E. coli isolates were categorized into 4 phylogenetic groups A (39.4%), B2 (24.25%), D (24.25%) and B1 (12.1%). The pathogenic B2 and D groups were mainly typical for the Laridae family. Among the 28 virulence factors (Vfs) detected in pathogenic phylogenetic groups B2 and D, 7 were exclusively found in those groups (sfa, vat, tosA, tosB, hly, usp, cnf), while 4 VFs (fecA, fyuA, irp2, kspMTII) showed a statistically significant association (P≤0.05) with phylogroups A and B1. Our results indicated that strains belonging to commensal phylogroups A/B1 possess extensive iron acquisition systems (93,9%) and autotransporters (60,6%), typical for pathogens, hence we suggest that these strains evolve towards higher levels of virulence. This study, which is a point assessment of the virulence and drug resistance potential of wild birds, confirms the importance of taking wild birds as a reservoir of strains that pose a growing threat to humans. The E. coli analyzed in our study derive from different phylogenetic groups and possess an arsenal of antibiotic resistance genes and virulence factors that contribute to their ability to cause diseases.

  • Antiferromagnetic Order in the Rare-Earth Halide Perovskites CsEuBr3 and CsEuCl3
    • Daniel B. Straus
    • Tomasz Klimczuk
    • Xianghan Xu
    • Robert J. Cava
    2022 CHEMISTRY OF MATERIALS

    Bulk CsEuBr3 and CsEuCl3 are experimentally shown to be magnetic semiconductors that order antiferromagnetically at Néel temperatures of 2.0 K and 1.0 K, respectively. Given that nanoparticles and thin films of CsEuCl3 have been reported to order ferromagnetically at a similar temperature, our observation of antiferromagnetic ordering in CsEuBr3 and CsEuCl3 expands the possible applications of halide perovskites to now include spintronic devices where both ferromagnetic and antiferromagnetic devices can be fabricated from a single material. The conclusion that CsEuCl3 can be used as a switchable magnetic material is also supported by our density-functional theory calculations.

  • Antifungal Effect of Penicillamine Due to the Selective Targeting of L-Homoserine O-Acetyltransferase
    • Aleksandra Kuplińska
    • Kamila Rząd
    • Marek Wojciechowski
    • Sławomir Milewski
    • Iwona Gabriel
    2022 Full text INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Due to the apparent similarity of fungal and mammalian metabolic pathways, the number of established antifungal targets is low, and the identification of novel ones is highly desirable. The results of our studies, presented in this work, indicate that the fungal biosynthetic pathway of L-methionine, an amino acid essential for humans, seems to be an attractive perspective. The MET2 gene from Candida albicans encoding L-homoserine O-acetyltransferase (CaMet2p), an enzyme catalyzing the first step in that pathway, was cloned and expressed as the native or the oligo-His-tagged fusion protein in Escherichia coli. The recombinant enzymes were purified and characterized for their basic molecular properties and substrate specificities. The purified MET2 gene product revealed the appropriate activity, catalyzed the conversion of L-homoserine (L-Hom) to O-acetyl-L-homoserine (OALH), and exhibited differential sensitivity to several L-Hom or OALH analogues, including penicillamine. Surprisingly, both penicillamine enantiomers (L- and D-Pen) displayed comparable inhibitory effects.The esults of the docking of L- and D-Pen to the model of CaMet2p confirmed that both enantiomeric forms of the inhibitor are able to bind to the catalytic site of the enzyme with similar affinities and a similar binding mode. The sensitivity of some fungal cells to L-Pen, depending on the presence or absence of L-Met in the medium, clearly indicate Met2p targeting. Moreover, C. glabrata clinical strains that are resistant to fluconazole displayed a similar susceptibility to L-Pen as the wild-type strains. Our results prove the potential usefulness of Met2p as a molecular target for antifungal chemotherapy.

  • Anti-plane waves in an elastic thin strip with surface energy
    • Gennadi Mikhasev
    • Marina Botogova
    • Victor Eremeev
    2022 Full text PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES

    We consider anti-plane motions of an elastic plate taking into account surface energy within the linear Gurtin–Murdoch surface elasticity. Two boundary-value problems are considered that describe complete shear dynamics of a plate with free faces or with free and clamped faces, respectively. These problems correspond to anti-plane dynamics of an elastic film perfectly or non-perfectly attached to a rigid substrate. Detailed analysis of dispersion relations is provided. In particular, the influence of the ratio of a plate thickness to characteristic length on the dispersion curves is analysed.

  • Aplikacja demonstrująca działanie kodów fontannowych
    • Kamila Haustein
    • Marek Blok
    2022 Full text Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    Istotną cechą kodów fontannowych jest możliwość odtwarzania nadawanych danych niezależnie od jakości kanału. Wynika to z tego, że kody te nie mają z góry założonej zawartości informacyjnej, a kolejne symbole nadmiarowe są generowane, dopóki jest taka potrzeba. Jest to szczególnie przydatne w transmisjach broadcastowych, bo każdy z odbiorców może zdekodować dane tak wcześnie, na ile pozwala jakość łącza. Aby przybliżyć funkcjonowanie tych kodów studentom, powstała zaprezentowana w pracy aplikacja demonstrująca ich kodowanie i dekodowanie.

  • Application analysis of a hybrid solid oxide fuel cell-gas turbine system for marine power plants
    • Serhiy Serbin
    • Nikolay Washchilenko
    • Oleksandr Cherednichenko
    • Kateryna Burunsuz
    • Marek Dzida
    • Daifen Chen
    2022 Full text Ships and Offshore Structures

    The results of theoretical studies of the possibilities of using hybrid solid oxide fuel cell–gas turbine (SOFC-GT) systems for marine power plants are presented. A 500 kW auxiliary marine power plant scheme using stacks of SOFCs in combination with a regenerative gas turbine operating with over-expansion based on our recent patent application is proposed. The results of mathematical modelling showed the opportunity to obtain a hybrid scheme efficiency of about 55% with the optimal values of the gas turbine compression ratio 2.0–2.2 and the exhauster compressor ratio 1.3–1.4. The application of the considered hybrid SOFC-GT system gives an increase in electrical efficiency by 19% in comparison with a cycle without a gas turbine. The aerodynamic structure of chemically reacting flows in a combustor is determined, as well as the features of the formation of toxic components during the combustion of SOFC off-gas with very low heating value

  • Application of a Gas Sensor Array to Effectiveness Monitoring of Air Contaminated with Toluene Vapors Absorption Process
    • Dominik Dobrzyniewski
    • Bartosz Szulczyński
    • Jacek Gębicki
    2022 Full text Journal of Ecological Engineering

    This article demonstrates the application of a gas sensor array to monitor the effectiveness of the absorption process of air stream purification from odorous compounds (toluene vapors). A self-constructed matrix consisting of five commercially available gas sensors was used. Multiple linear regression (MLR) was selected as the statistical technique used to calibrate the matrice. Gas chromatography coupled with a flame ionization detector (GC-FID) was used as a reference analytical technique, which enabled to obtain reliable quantitative determinations of toluene concentration in the samples. A commercially available absorption liquid dedicated to non-polar compounds was used as an absorbent. The process was carried out in two identical systems: in first, pure toluene was absorbed and in the second, toluene vapor contaminated with acetone. This approach allowed verifying the selectivity of the prepared MLR calibration model for process control in the case of the presence of more or less expected pollutants in the treated gas. The results obtained with the gas sensor array were related to the reference technique and they confirm the usefulness and advisability of using these devices to monitor the absorption processes as a cheaper and more time-efficient alternative to chromatographic methods. The root mean square error (RMSE) in absorptivity determination between the results received with the analytical and sensor techniques was 0.019 and 0.041 when treating pure toluene vapors and its vapors with acetone, respectively. Compared to instrumental techniques, sensor matrices are technologically less complex, useful for laboratory purposes, as well as showing application potential for field studies. However, it is necessary to develop more sensitive and selective chemical gas sensor arrays and better master advanced data processing and identification techniques.

  • Application of a hybrid mechanistic/machine learning model for prediction of nitrous oxide (N2O) production in a nitrifying sequencing batch reactor
    • Mohamad-Javad Mehrani
    • Faramarz Bagherzadeh
    • Min Zheng
    • Przemysław Kowal
    • Dominika Sobotka
    • Jacek Mąkinia
    2022 Full text PROCESS SAFETY AND ENVIRONMENTAL PROTECTION

    Nitrous oxide (N2O) is a key parameter for evaluating the greenhouse gas emissions from wastewater treatment plants. In this study, a new method for predicting liquid N2O production during nitrification was developed based on a mechanistic model and machine learning (ML) algorithm. The mechanistic model was first used for simulation of two 15-day experimental trials in a nitrifying sequencing batch reactor. Then, model predictions (NH4-N, NO2-N, NO3-N, MLSS, MLVSS) along with the recorded online measurements (DO, pH, temperature) were used as input data for the ML models. The data from the experiments at 20 °C and 12 °C, respectively, were used for training and testing of three ML algorithms, including artificial neural network (ANN), gradient boosting machine (GBM), and support vector machine (SVM). The best predictive model was the ANN algorithm and that model was further subjected to the 95% confidence interval analysis for calculation of the true data probability and estimating an error range of the data population. Moreover, Feature Selection (FS) techniques, such as Pearson correlation and Random Forest, were used to identify the most relevant parameters influencing liquid N2O predictions. The results of FS analysis showed that NH4-N, followed by NO2-N had the highest correlation with the liquid N2O production. With the proposed ap- proach, a prompt method was obtained for enhancing prediction of the liquid N2O concentrations for short- term studies with the limited availability of measured data.

  • Application of deep eutectic solvents in atomic absorption spectrometry
    • Vasil Andruch
    • Radoslav Halko
    • Jozef Tuček
    • Justyna Płotka-Wasylka
    2022 Full text TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    Atomic absorption spectrometry (AAS) is a widely applied technique for metal quantification due to its practicality, easy use and low cost. However, to improve the metrological characteristics of AAS, in particular the sensitivity and the detection limit, sample pretreatment is commonly used before the detection step itself. In consideration of the principles of Green Analytical Chemistry, new solvents are being introduced into analytical practice. Deep eutectic solvents (DES) are often employed in the sample preparation prior to AAS due to their unique properties. This article deals with the potential of DES for the separation of metals and metalloids followed by AAS quantification. The primary focus is on DES employed in various liquideliquid microextraction procedures, such UA-LPME, VA-LPME and DLLME; however, examples of less frequently occurring combinations are also presented. We believe that this review can be useful for readers as a starting point for future research in the field of DESs and their application in AAS.

  • Application of deep eutectic solvents in bioanalysis
    • Vasil Andruch
    • Alica Varfalvyová
    • Radoslav Halko
    • Natalia Jatkowska
    • Justyna Płotka-Wasylka
    2022 Full text TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    The application of deep eutectic solvents (DESs) is sharply surging as a green alternative to conventional solvents due to their unique properties in terms of simplicity of preparation, designability and low cost. A great deal of attention has been paid to the application of these green solvents in analytical chemistry in recent years, and a lot of interesting work has been reported. This review summarizes the most relevant applications of DESs in bioanalysis related to both sample preparation and analyte quantification. Special attention is devoted to the discussion of practical applications for various types of biological samples (blood, plasma, serum, urine, saliva, hair, tear, sweat), with a focus on the advantages of DES-based methods over traditional ones. We cover the articles that were available online up to the end of January 2022. The applications of the reported techniques are summarized in tables.

  • Application of Doubly Connected Dominating Sets to Safe Rectangular Smart Grids
    • Joanna Cyman
    • Joanna Raczek
    2022 Full text ENERGIES

    Smart grids, together with the Internet of Things, are considered to be the future of the electric energy world. This is possible through a two-way communication between nodes of the grids and computer processing. It is necessary that the communication is easy and safe, and the distance between a point of demand and supply is short, to reduce the electricity loss. All these requirements should be met at the lowest possible cost. In this paper, we study a two-dimensional rectangular grid graph which is considered to be a model of a smart grid; nodes of the graph represent points and devices of the smart grid, while links represent possible ways of communication and energy transfer. We consider the problem of choosing the lowest possible number of locations (nodes, points) of the grid which could serve as energy sources (or a source of different resources) to other nodes in such a way that we ensure reduction in electricity loss and provide safe communication and resistance to failures and increases in energy demand.Therefore, we study minimum doubly connected dominating sets in grid graphs. We show that the proposed solutions are the best possible in terms of the number of source points for the case of narrow grid graphs and we give upper and lower bounds for the case of wide grid graphs.

  • Application of g-C3N4/ZnO nanocomposites for fabrication of anti-fouling polymer membranes with dye and protein rejection superiority
    • Vahid Vatanpour
    • Seyed Soroush Mousavi Khadem
    • Ahmad Dehqan
    • Shadi Paziresh
    • Mohammad Ganjali
    • Mehdi Mehrpooya
    • Eslam Pourbasheer
    • Alireza Badiei
    • Amin Esmaeili
    • Ismail Koyuncu
    • Ghasem Naderi
    • Navid Rabiee
    • Otman Abida
    • Sajjad Habibzadeh
    • Mohammad Saeb
    2022 JOURNAL OF MEMBRANE SCIENCE

    Polysulfone (PSf) membranes are privileged for water and wastewater treatment, but because of their hydrophobic nature, they suffer from fouling, which lowers their performance and lifetime. In this work, g-C3N4 and g-C3N4/ZnO nanomaterials were synthesized via a hydrothermal method to modify the PSf membrane for effective dye separation and reduction of organic fouling. Since g-C3N4/ZnO possesses –OH and –NH reactive groups, g-C3N4/ZnO/PSf membrane revealed higher porosity, hydrophilicity, negative surface charge, and lower contact angle. The results of filtration analysis also showed a higher performance for nanomembranes with respect to the neat PSf. Permeability and fouling resistance of neat PSf membrane were well below those of nanocomposite membranes, such that by incorporation of 0.5 wt% g-C3N4/ZnO nanocomposite in PSf they significantly improved to 85.93 L/m2 h bar and 90%, respectively. The rejection rate was also increased for both types of dyes used in this study (99.9% for Reactive green 19 and 85.5% for Reactive Yellow 160). The outcome of this research would suggest the application of graphitic nitride nanomaterials for developing highly efficient polymer membranes.

  • Application of mechanistic and data-driven models for nitrogen removal in wastewater treatment systems
    • Mohammad Javad Mehrani
    2022 Full text

    In this dissertation, the application of mechanistic and data-driven models in nitrogen removal systems including nitrification and deammonification processes was evaluated. In particular, the influential parameters on the activity of the Nitrospira activity were assessed using response surface methodology (RSM). Various long-term biomass washout experiments were operated in two parallel sequencing batch reactor (SBR) with a different temperature, aeration mode and substrates and were used for the modelling data source. In the next step, three extension models for the complete ammonia oxidation (comammox) process were developed using the GPS-X simulation software. The extensions were incorporated in the conventional two-step nitrification model. The developed comammox model accurately predicted nitrogen species, biomass concentrations and microbiological indexes. In addition, the contribution of the comammox in nitrogen conversion was generated using Sankey graphs under different operational conditions. Moreover, prediction of the N2O emission in the liquid phase during the nitrification systems was evaluated using hybrid mechanistic/machine learning (ML) method (GPS-X and python programming). In addition, various feature selections (FS) was applied to figure out the effective factors on the production of the N2O emission in the SBR nitrification systems. Finally, a model-based optimization of aeration was performed using GPS-X on the mainstream deammonification system was carried out, in which the DO value and on/off ratio were the variables and N removal rate (NRR) and N removal efficiency (NRE) were the target of optimization.

  • Application of Multinomial Logistic Regression to Model the Impact of Rainfall Genesis on the Performance of Storm Overflows: Case Study
    • Bartosz Szeląg
    • Roman Suligowski
    • Grzegorz Majewski
    • Przemysław Kowal
    • Adrian Bralewski
    • Karolina Bralewska
    • Ewa Anioł
    • Wioletta Rogula-Kozłowska
    • Francesco De Paola
    2022 WATER RESOURCES MANAGEMENT

    In this study, a mathematical model was proposed to analyze the performance of storm overfows. The model included the infuence of rainfall genesis on the duration of storm overfow, its volume, and the maximum instantaneous fow. The multinomial logistic regression model, which has not been used so far to model objects located in a stormwater system, was proposed to simulate the duration of storm overfow. The Iman–Conover method, using the theoretical cumulative distributions determined on the basis of 45 – year rainfall sequences, was adopted to simulate the rainfall characteristics describing the overfow performance (total and maximum 30-min rainfall depth and duration). The simulations showed a signifcant impact of rainfall genesis on the parameters of the storm overfow. The model and the results presented in this study can be used at the stage of dimensioning storm overfows and to create an early warning system against undesirable phenomena in the stormwater system within urban catchments.

  • Application of persulfate-based oxidation processes to address diverse sustainability challenges: A critical review
    • Dagang Lin
    • Yu Fu
    • Xiaodie Li
    • Lingli Wang
    • Meiru Hou
    • Dongdong Hu
    • Qingchao Li
    • Zhen Zhang
    • Chunxiao Xu
    • Sifan Qiu
    • Zhaohui Wang
    • Grzegorz Boczkaj
    2022 JOURNAL OF HAZARDOUS MATERIALS

    Over the past years, persulfate (PS) is widely applied due to their high versatility and efficacy in decontamination and sterilization. While treatment of organic chemicals, remediation of soil and groundwater, sludge treatment, disinfection on pathogen microorganisms have been covered by most published reviews, there are no comprehensive and specific reviews on its application to address diverse sustainability challenges, including solid waste treatment, resources recovery and regeneration of ecomaterials. PS applications mainly rely on direct oxidation by PS itself or the reactive sulfate radical (SO4•−) or hydroxyl radical (•OH) from the activation of peroxodisulfate (PDS, S2O82−) or peroxymonosulfate (PMS, HSO5−) in SO4•−-based advanced oxidation processes (SO4•−-AOPs). From a broader perspective of environmental cleanup and sustainability, this review summarizes the various applications of PS except pollutant decontamination and elaborates the possible reaction mechanisms. Additionally, the differences between PS treatment and conventional technologies are highlighted. Challenges, research needs and future prospect are thus discussed to promote the development of the applications of PS-based oxidation processes in niche environmental fields. In all, this review is a call to pay more attention to the possibilities of PS application in practical resource reutilization and environmental protection except widely reported pollutant degradation.